Sample records for model regions source

  1. Regional Oxidant Model (ROM), Source code and test data (Version 2. 1). Model-Simulation

    SciTech Connect (OSTI)

    Not Available

    1991-01-01T23:59:59.000Z

    The Regional Oxidant Model (ROM) is a three-dimensional photochemical Eulerian grid model designed to simulate ambient concentrations of ozone and related species. ROM is a 3-layer model with a horizontal resolution of approximately 19 km; each grid cell has dimensions of 1/6 degree latitude by 1/4 degree longitude. The typical horizontal extent of the modeling domain is 1000 km. The model is designed to simulate hourly regional concentrations of ozone during largely stagnant summertime conditions that are associated with elevated smog episodes. The model is designed so that its preprocessors run on a VAX and the core model runs on an IBM mainframe. A typical 3-day simulation of the core model for the northeastern U.S. uses 9.5 hours of CPU on an IBM 3090. A total of 19 computer tapes comprise the release of the ROM (Version 2.1). Six of the tapes were generated on an IBM, and 13 tapes were generated on a VAX. The tapes contain source code, sample runstreams, and test data for a 3-day simulation. Potential users of the ROM should be aware that the modeling system is complex and requires extensive computer resources. The services of engineers, meteorologists, or computer scientists experienced in photochemical grid modeling are required.

  2. Regional Oxidant Model (ROM), (Source code only) (Version 2. 1). Model-Simulation

    SciTech Connect (OSTI)

    Not Available

    1991-01-01T23:59:59.000Z

    The Regional Oxidant Model (ROM) is a three-dimensional photochemical Eulerian grid model designed to simulate ambient concentrations of ozone and related species. ROM is a 3-layer model with a horizontal resolution of approximately 19 km; each grid cell has dimensions of 1/6 degree latitude by 1/4 degree longitude. The typical horizontal extent of the modeling domain is 1000 km. The model is designed to simulate hourly regional concentrations of ozone during largely stagnant summertime conditions that are associated with elevated smog episodes. The model is designed so that its preprocessors run on a VAX and the core model runs on an IBM mainframe. A typical 3-day simulation of the core model for the northeastern U.S. uses 9.5 hours of CPU on an IBM 3090. A total of 19 computer tapes comprise this release of the ROM (Version 2.1). Six of the tapes were generated on an IBM, and 13 tapes were generated on a VAX. The tapes contain source code, sample runstreams, and test data for a 3-day simulation. Potential users of the ROM should be aware that the modeling system is complex and requires extensive computer resources. The services of engineers, meteorologists, or computer scientists experienced in photochemical grid modeling are required.

  3. Using Local and Regional Air Quality Modeling and Source Apportionment Tools to Evaluate Vehicles and Biogenic Emission Factors

    E-Print Network [OSTI]

    Kota, Sri H

    2014-07-25T23:59:59.000Z

    and inventories of CO, NO_(x) and VOCs from on-road vehicles estimated by vehicle emission factor models and biogenic emissions of isoprene estimated by a popular biogenic emission model are evaluated using local and regional scale air quality modeling and source...

  4. Identification of potential sources and source regions of fine ambient particles measured at Gosan background site in Korea using advanced hybrid receptor model combined with positive matrix factorization - article no. D22217

    SciTech Connect (OSTI)

    Han, J.S.; Moon, K.J.; Kim, Y.J. [National Institute of Environmental Research, Inchon (Republic of Korea). Dept. of Air Quality Research

    2006-11-15T23:59:59.000Z

    The size- and time-resolved measurement of particulate trace elements was made using an eight-stage Davis Rotating Unit for Monitoring sampler and synchrotron X-ray fluorescence system from 29 March to 29 May in 2002 at Gosan, Korea, which is one of the representative background sites in east Asia. A sa result, continuous 3-hour average concentrations were obtained for 19 elements including S, Si, Al, Fe, Ca, Cl, Cu, Zn, Ti, K, Mn, Pb, Ni, V, Se, As, Rb, Cr, and Br. Positive matrix factorization (PMF) method was applied to the size-resolved aerosol data sets in order to identify the possible sources and to estimate their contribution to particulate matter mass in each size range. Twelve sources were then resolved in the fine size range ( 0.07 to 1.15 {mu}m), including continental aerosol, biomass burning, coal combustion, oil heating furnace, residual oil-fired boiler, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, copper smelter, and volcanic emission. A newly developed hybrid receptor model, concentration, retention time, and source emission weighted trajectory (CRSWT) was then applied to the source intensities derived from the PMF analysis by incorporating meteorological and source inventory information of the study region in order to suggest the regional information of long-range transported fine aerosol sources. The CRSWT model was able to resolve highly potential source areas and pathways for the fine ambient aerosol at the Gosan background site.

  5. Tracing meteorite source regions through asteroid spectroscopy

    E-Print Network [OSTI]

    Thomas, Cristina Ana

    2009-01-01T23:59:59.000Z

    By virtue of their landing on Earth, meteorites reside in near-Earth object (NEO) orbits prior to their arrival. Thus the population of observable NEOs, in principle, give the best representation of meteorite source bodies. ...

  6. alamos source region: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    activity of Sgr A* in the past. E. Churazov; M. Gilfanov; R. Sunyaev; S. Kuznetsov 1999-01-13 17 An Optical Source Catalog of the North Ecliptic Pole Region Astrophysics...

  7. Source contributions at regional distances. Final report, 9 Aug 88-31 May 91

    SciTech Connect (OSTI)

    Koch, K.; Soroka, W.; Stump, B.

    1991-05-14T23:59:59.000Z

    In order to quantify the effects of different components of the explosion source function on far regional seismograms (900-2000km) a one-dimensional velocity model is developed for seismic waves traveling across the Basin and Range. This model is constrained by broadband data recorded at the Lajitas seismic station. Complete synthetic seismograms are developed for the model utilizing the extended reflectivity technique. Pg, Pn, mantle P, Lg and surface waves are included in the data as well as in the synthetics. The P velocity model follows closely that of Olsen et al. (1980,1) developed from shorter offset data. The lack of Sn in the observational data requires a thin mantle S lid not included in these earlier models. The complete set of synthetics replicate the transition of crustal P energy to mantle P around 900km, the rapid decay of Pg beyond 1000km, the lack of Sn energy, and the lower frequency content of Lg relative to the body wave arrivals. This wave propagation model is used to quantify the source effects from an explosion and spall source function. The explosion source is much less sensitive to depth of burial differences than the spall source. Spall and explosion source parameters constrained by near source data indicate that the importance of spall to the Lg phase is source time function dependent. If the peak of the spall source falls outside the low frequency window for Lg, then it has negligible contribution to the regional waveforms.

  8. A Framework for Modeling Uncertainty in Regional Climate Change

    E-Print Network [OSTI]

    Monier, Erwan

    In this study, we present a new modeling framework and a large ensemble of climate projections to investigate the uncertainty in regional climate change over the US associated with four dimensions of uncertainty. The sources ...

  9. MODELING, SIMULATION AND OPTIMIZATION OF GROUND SOURCE

    E-Print Network [OSTI]

    MODELING, SIMULATION AND OPTIMIZATION OF GROUND SOURCE HEAT PUMP SYSTEMS By MUHAMMAD HAIDER KHAN AND OPTIMIZATION OF GROUND SOURCE HEAT PUMP SYSTEMS Thesis Approved..................................................................................................................... 1 1.1 Overview of Ground Source Heat Pump Systems.............................................. 1 1

  10. Regions in Energy Market Models

    SciTech Connect (OSTI)

    Short, W.

    2007-02-01T23:59:59.000Z

    This report explores the different options for spatial resolution of an energy market model--and the advantages and disadvantages of models with fine spatial resolution. It examines different options for capturing spatial variations, considers the tradeoffs between them, and presents a few examples from one particular model that has been run at different levels of spatial resolution.

  11. Regional Climate Modeling: Progress, Challenges, and Prospects

    SciTech Connect (OSTI)

    Wang, Yuqing; Leung, Lai R.; McGregor, John L.; Lee, Dong-Kyou; Wang, Wei-Chyung; Ding, Yihui; Kimura, Fujio

    2004-12-01T23:59:59.000Z

    Regional climate modeling with regional climate models (RCMs) has matured over the past decade and allows for meaningful utilization in a broad spectrum of applications. In this paper, latest progresses in regional climate modeling studies are reviewed, including RCM development, applications of RCMs to dynamical downscaling for climate change assessment, seasonal climate predictions and climate process studies, and the study of regional climate predictability. Challenges and potential directions of future research in this important area are discussed, with the focus on those to which less attention has been given previously, such as the importance of ensemble simulations, further development and improvement of regional climate modeling approach, modeling extreme climate events and sub-daily variation of clouds and precipitation, model evaluation and diagnostics, applications of RCMs to climate process studies and seasonal predictions, and development of regional earth system models. It is believed that with both the demonstrated credibility of RCMs’ capability in reproducing not only monthly to seasonal mean climate and interannual variability but also the extreme climate events when driven by good quality reanalysis and the continuous improvements in the skill of global general circulation models (GCMs) in simulating large-scale atmospheric circulation, regional climate modeling will remain an important dynamical downscaling tool for providing the needed information for assessing climate change impacts and seasonal climate predictions, and a powerful tool for improving our understanding of regional climate processes. An internationally coordinated effort can be developed with different focuses by different groups to advance regional climate modeling studies. It is also recognized that since the final quality of the results from nested RCMs depends in part on the realism of the large-scale forcing provided by GCMs, the reduction of errors and improvement in physics parameterizations in both GCMs and RCMs remain a priority for climate modeling community.

  12. Characterization and modeling of the heat source

    SciTech Connect (OSTI)

    Glickstein, S.S.; Friedman, E.

    1993-10-01T23:59:59.000Z

    A description of the input energy source is basic to any numerical modeling formulation designed to predict the outcome of the welding process. The source is fundamental and unique to each joining process. The resultant output of any numerical model will be affected by the initial description of both the magnitude and distribution of the input energy of the heat source. Thus, calculated weld shape, residual stresses, weld distortion, cooling rates, metallurgical structure, material changes due to excessive temperatures and potential weld defects are all influenced by the initial characterization of the heat source. Understandings of both the physics and the mathematical formulation of these sources are essential for describing the input energy distribution. This section provides a brief review of the physical phenomena that influence the input energy distributions and discusses several different models of heat sources that have been used in simulating arc welding, high energy density welding and resistance welding processes. Both simplified and detailed models of the heat source are discussed.

  13. Aerosol acidity in rural New England: Temporal trends and source region analysis

    E-Print Network [OSTI]

    Fischer, Emily V.

    the dissociation of sulfuric acid (H2SO4) that condenses after forming via the gas phase oxidation of sulfurAerosol acidity in rural New England: Temporal trends and source region analysis L. D. Ziemba,1,2 E. Talbot (2007), Aerosol acidity in rural New England: Temporal trends and source region analysis, J

  14. MODELING, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP

    E-Print Network [OSTI]

    MODELING, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS, VERIFICATION AND OPTIMIZATION OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS Thesis Approved by: Dr.................................................................................................................... 16 MODELING OF HYBRID GROUND SOURCE HEAT PUMP SYSTEMS IN ENERGYPLUS

  15. Sandia National Laboratories: open source WEC modeling tool

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    source WEC modeling tool Sandia, NREL Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim On July 29, 2014, in Computational Modeling & Simulation, Energy, News,...

  16. Modeling-Computer Simulations At Nw Basin & Range Region (Biasi...

    Open Energy Info (EERE)

    Location Northwest Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful regional reconnaissance DOE-funding...

  17. Source rock evaluation, oil-source rock correlation, and kinetic modeling - San Juan Sag, CO

    SciTech Connect (OSTI)

    Clayton, J.L. (Geological survey, Denver, CO (USA)); Gries, R.R.

    1990-05-01T23:59:59.000Z

    Recently, oil and gas shows have been reported in Cretaceous and Tertiary rocks of the San Juan sag, and minor oil production was established from volcanic rocks (Kirby Petroleum 1 Jynnifer well, Sec. 9, T40N, R5E.). Potential source rocks present in the San Juan sag are the upper and lower (including the Niobrara Member) Mancos Shale (Upper Cretaceous). The combined upper and lower Mancos Shale is about 666 m thick and contains between about 0.5 and 5.5% organic carbon, although most values are between about 1.5 and 2.0%. The Niobrara Member of the lower Mancos Shale has the highest overall organic matter content in the section (organic carbon averages <2.0%). Pyrolysis and solvent extraction data (typically 2,000-6,000 and 1,000-4,000 ppm, respectively) indicate that the upper and lower Mancos Shale and the Niobrara Member are all good potential source rocks for oil and gas. Oil-source rock correlations using gas chromatography, mass spectrometry, and stable carbon isotope ratios indicate that the upper Mancos Shale is the most likely source for the oil produced from the 1 Jynnifer discovery well. The source of the oil produced from the nearby Gramps field is less certain, but may be the lower Mancos Shale or Niobrara Member. The hydrocarbon generation history of the San Juan sag is complex because of highly variable heat flow in the area caused by Oligocene volcanism. Sills have caused thermal alteration of organic matter in shales on a local scale, and larger volcanic bodies may have produced proportionality larger thermal effects. More regional heating by larger volcanic bodies is an important factor in the oil generation history of the area. The authors have constructed kinetic models at several locations in the area to estimate the timing and amount of hydrocarbon products generated from the source rocks. The main phase of oil and gas generation and expulsion occurred during the Oligocene.

  18. The CouncilThe Council''s Regionals Regional Portfolio ModelPortfolio Model

    E-Print Network [OSTI]

    Summer Winter Coal Operating CostsOperating Costs Model Overview #12;Page 3 5 Sources of Uncertainty Power Plan All of those to the left, except, perhaps, aluminum price Power plant construction costs, and labor costs Retirement Risk Carrying the forward-going fixed cost of an unused plant Undervaluing

  19. active region model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    model (Wheatland and Glukhov 1998; Wheatland 2008; Wheatland 2009). The magnetic free energy of the model active region varies in time due to a prescribed (deterministic)...

  20. Southern California Earthquake Center - SCEC1: Final Report Summary Alternative Earthquake Source Characterization for the Los Angeles Region

    SciTech Connect (OSTI)

    Foxall, B

    2003-02-26T23:59:59.000Z

    The objective my research has been to synthesize current understanding of the tectonics and faults of the Los Angeles Basin and surrounding region to quantify uncertainty in the characterization of earthquake sources used for geologically- and geodetically-based regional earthquake likelihood models. This work has focused on capturing epistemic uncertainty; i.e. uncertainty stemming from ignorance of the true characteristics of the active faults in the region and of the tectonic forces that drive them. In the present context, epistemic uncertainty has two components: First, the uncertainty in source geometrical and occurrence rate parameters deduced from the limited geological, geophysical and geodetic observations available; and second. uncertainties that result from fundamentally different interpretations of regional tectonic deformation and faulting. Characterization of the large number of active and potentially active faults that need to be included in estimating earthquake occurrence likelihoods for the Los Angeles region requires synthesis and evaluation of large amounts of data and numerous interpretations. This was accomplished primarily through a series of carefully facilitated workshops, smaller meetings involving key researchers, and email groups. The workshops and meetings were made possible by the unique logistical and financial resources available through SCEC, and proved to be extremely effective forums for the exchange and critical debate of data and interpretations that are essential in constructing fully representative source models. The main products from this work are a complete source model that characterizes all know or potentially active faults in the greater Los Angeles region. which includes the continental borderland as far south as San Diego, the Ventura Basin, and the Santa Barbara Channel. The model constitutes a series of maps and representative cross-sections that define alternative fault geometries, a table containing rault geometrical and slip-rate parameters, including full uncertainty distributions, and a set of logic trees that define alternative source characterizations, particularly for sets of fault systems having inter-dependent geometries and kinematics resulting from potential intersection and interaction in the sub-surface. All of these products exist in a form suitable for input to earthquake likelihood and seismic hazard analyses. In addition, moment-balanced Poissonian earthquake rates for the alternative multi-segment characterizations of each fault system have been estimated. Finally, this work has served an important integrative function in that the exchange and debate of data, results and ideas that it has engendered has helped to focus SCEC research over the past six years on to key issues in tectonic deformation and faulting.

  1. ADVANCES IN MODELING OF GROUND-SOURCE HEAT

    E-Print Network [OSTI]

    ADVANCES IN MODELING OF GROUND-SOURCE HEAT PUMP SYSTEMS By ANDREW D. CHIASSON Bachelor of Applied 1999 #12;ii ADVANCES IN MODELING OF GROUND-SOURCE HEAT PUMP SYSTEMS Thesis Approved: Thesis Adviser..............................................................................................................1 1.1. Overview of Ground-Source Heat Pump Systems ..............................................1 1

  2. Model for a transformer-coupled toroidal plasma source

    SciTech Connect (OSTI)

    Rauf, Shahid; Balakrishna, Ajit; Chen Zhigang; Collins, Ken [Applied Materials, Inc., 974 E. Arques Avenue, Sunnyvale, California 94085 (United States)

    2012-01-15T23:59:59.000Z

    A two-dimensional fluid plasma model for a transformer-coupled toroidal plasma source is described. Ferrites are used in this device to improve the electromagnetic coupling between the primary coils carrying radio frequency (rf) current and a secondary plasma loop. Appropriate components of the Maxwell equations are solved to determine the electromagnetic fields and electron power deposition in the model. The effect of gas flow on species transport is also considered. The model is applied to 1 Torr Ar/NH{sub 3} plasma in this article. Rf electric field lines form a loop in the vacuum chamber and generate a plasma ring. Due to rapid dissociation of NH{sub 3}, NH{sub x}{sup +} ions are more prevalent near the gas inlet and Ar{sup +} ions are the dominant ions farther downstream. NH{sub 3} and its by-products rapidly dissociate into small fragments as the gas flows through the plasma. With increasing source power, NH{sub 3} dissociates more readily and NH{sub x}{sup +} ions are more tightly confined near the gas inlet. Gas flow rate significantly influences the plasma characteristics. With increasing gas flow rate, NH{sub 3} dissociation occurs farther from the gas inlet in regions with higher electron density. Consequently, more NH{sub 4}{sup +} ions are produced and dissociation by-products have higher concentrations near the outlet.

  3. A composite application of source and receptor models to fine particle concentrations in Portage, Wisconsin

    SciTech Connect (OSTI)

    Chow, J.C.; Severance, P.W.; Spengler, J.D.

    1985-01-01T23:59:59.000Z

    The research reported here extends source apportioment techniques by combining four air quality model types to establish multi-scale source/receptor relationships. The selected models are: Branching Atmospheric Trajectory (BAT) model for regional-scale contributors; Principal Component Analysis (PCA) receptor model for urban and regional-scale contributors; Chemical Mass Balance (CMB) receptor model for urban- and regional-scale contributors; Industrial Source Complex Short-Term (ISC-ST) dispersion model for urban-scale contributors. The framework in which these models are placed allows each one to be replaced with better ones when these new models have been demonstrated to be superior. The theoretical basis, previous applications, and the results of model evaluation studies are summarized by Chow in great detail and will not be presented here. The objectives of this research are: to develop a method for multi-scale composite modeling applications; to define the data requirements; and to apportion local and distract pollution sources using the composite modeling strategy. Results from the entire research effort are too lengthy to include here. This paper focuses on CMB portion of the method. Trajectory and Principal Component Analyses were reported earlier.

  4. Role of latitude of source region in Solar Energetic Particle events

    E-Print Network [OSTI]

    Sanahuja, Blai

    PR1 2HE, UK Department of Physics, University of Helsinki, 00014 Helsinki, Finland Abstract. Solar up to near- relativistic energies. Some of these particles can escape the solar atmosphere and travelRole of latitude of source region in Solar Energetic Particle events S. Dalla and N. Agueda1

  5. State of the Art of Air-source Heat Pump for Cold Regions 

    E-Print Network [OSTI]

    Tian, C.; Liang, N.

    2006-01-01T23:59:59.000Z

    In this paper, research on air source heat pump systems for cold regions in recent years is first summarized and compared. These systems can be divided into three kinds: a single-stage compression heat pump, liquid/vapor injection heat pump, and a...

  6. Mats Lindroos, Cristina Oyon and Stevey OECD "A High Power Spallation Source in each Global Region"

    E-Print Network [OSTI]

    McDonald, Kirk

    ESS Mats Lindroos, Cristina Oyon and Stevey Peggs #12;ESS 2 #12;OECD "A High Power Spallation Source in each Global Region" SNS Oak Ridge J-PARC Tokai ESS in Lund #12;ESS: Site selection process · ESS high up on the ESFRI list Th ti biddi f th it (Bilb L d d· Three consortia bidding for the site

  7. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    SciTech Connect (OSTI)

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01T23:59:59.000Z

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

  8. Coupling of a regional atmospheric model (RegCM3) and a regional oceanic model (FVCOM) over the maritime continent

    E-Print Network [OSTI]

    Wei, Jun

    Climatological high resolution coupled climate model simulations for the maritime continent have been carried out using the regional climate model (RegCM) version 3 and the finite volume coastal ocean model (FVCOM) ...

  9. Modeling-Computer Simulations At Northern Basin & Range Region...

    Open Energy Info (EERE)

    navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Northern Basin & Range Region (Biasi, Et Al., 2009) Exploration...

  10. Modeling-Computer Simulations At Northern Basin & Range Region...

    Open Energy Info (EERE)

    Northern Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown References J. W. Pritchett...

  11. Modeling-Computer Simulations At Nw Basin & Range Region (Pritchett...

    Open Energy Info (EERE)

    navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Nw Basin & Range Region (Pritchett, 2004) Exploration Activity Details...

  12. Electric Potential Near The Extraction Region In Negative Ion Sources With Surface Produced Negative Ions

    SciTech Connect (OSTI)

    Fukano, A. [Monozukuri Department, Tokyo Metropolitan College of Industrial Technology, 1-10-40 Higashi-Ohi, Shinagawa-ku, Tokyo 140-0011 (Japan); Hatayama, A. [Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kouhoku-ku, Yokohama 223-8522 (Japan)

    2011-09-26T23:59:59.000Z

    The potential distribution near the extraction region in negative ion sources for the plasma with the surface produced negative ions is studied analytically. The potential is derived analytically by using a plasma-sheath equation, where negative ions produced on the Plasma Grid (PG) surface are considered in addition to positive ions and electrons. A negative potential peak is formed in the sheath region near the PG surface for the case of strong surface production of negative ions or for low energy negative ions. Negative ions are reflected by the negative potential peak near the PG and returned to the PG surface. This reflection mechanism by the negative potential peak possibly becomes a factor in negative ion extraction. It is also indicated that the potential difference between the plasma region and the wall decreases by the surface produced negative ions. This also has the possibility to contribute to the negative ion extraction.

  13. Independent Component Analysis For EEG Source Localization In Realistic Head Models

    E-Print Network [OSTI]

    Utah, University of

    1 Independent Component Analysis For EEG Source Localization In Realistic Head Models Leonid Zhukov Abstract-- A pervasive problem in neuroscience is determining which regions of the brain are active, given within the brain from electroencephalo- graphic (EEG) recordings is an ill-posed problem. Specifi- cally

  14. Independent Component Analysis For EEG Source Localization In Realistic Head Models

    E-Print Network [OSTI]

    Utah, University of

    1 Independent Component Analysis For EEG Source Localization In Realistic Head Models Leonid Zhukov Abstract--- A pervasive problem in neuroscience is determining which regions of the brain are active, given within the brain from electroencephalo­ graphic (EEG) recordings is an ill­posed problem. Specifi­ cally

  15. Nuisance Source Population Modeling for Radiation Detection System Analysis

    SciTech Connect (OSTI)

    Sokkappa, P; Lange, D; Nelson, K; Wheeler, R

    2009-10-05T23:59:59.000Z

    A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model must generate sources with a frequency of occurrence consistent with that found in actual movement of goods and people. Measured radiation detection data can indicate these frequencies, but, at present, such data are available only for a very limited set of locations and time periods. In this report, we make more general estimates of frequencies for NORM and medical sources using a range of data sources such as shipping manifests and medical treatment statistics. We also identify potential data sources for industrial source frequencies, but leave the task of estimating these frequencies for future work. Modeling of nuisance source populations is only useful if it helps in understanding detector system performance in real operational environments. Examples of previous studies in which nuisance source models played a key role are briefly discussed. These include screening of in-bound urban traffic and monitoring of shipping containers in transit to U.S. ports.

  16. MODELING OF VERTICAL GROUND LOOP HEAT EXCHANGERS FOR GROUND SOURCE

    E-Print Network [OSTI]

    MODELING OF VERTICAL GROUND LOOP HEAT EXCHANGERS FOR GROUND SOURCE HEAT PUMP SYSTEMS By CENK SOURCE HEAT PUMP SYSTEMS Thesis Approved: ___________________________________________ Thesis Adviser scale test data. The short-term behavior of ground-coupled heat pump systems is important for the design

  17. Spatial Models for Groundwater Behavioral Analysis in Regions of Maharashtra

    E-Print Network [OSTI]

    Sohoni, Milind

    Spatial Models for Groundwater Behavioral Analysis in Regions of Maharashtra M.Tech Dissertation on groundwater and classified the years into good year if water levels are above the seasonal model in that year such as land-use, local hydrogeology. #12;Contents 1 Introduction 1 1.1 Spatial Models

  18. High order hybrid discontinuous Galerkin regional ocean modelling

    E-Print Network [OSTI]

    Ueckermann, Mattheus Percy

    2014-01-01T23:59:59.000Z

    Accurate modeling of physical and biogeochemical dynamics in coastal ocean regions is required for multiple scientific and societal applications, covering a wide range of time and space scales. However, in light of the ...

  19. Regional Sources of Nitrous Oxide over the United States: Seasonal Variation and Spatial Distribution

    SciTech Connect (OSTI)

    Miller, S. M.; Kort, E. A.; Hirsch, A. I.; Dlugokencky, E. J.; Andrews, A. E.; Xu, X.; Tian, H.; Nehrkorn, T.; Eluszkiewicz, J.; Michalak, A. M.; Wofsy, S. C.

    2012-01-01T23:59:59.000Z

    This paper presents top-down constraints on the magnitude, spatial distribution, and seasonality of nitrous oxide (N{sub 2}O) emissions over the central United States. We analyze data from tall towers in 2004 and 2008 using a high resolution Lagrangian particle dispersion model paired with both geostatistical and Bayesian inversions. Our results indicate peak N{sub 2}O emissions in June with a strong seasonal cycle. The spatial distribution of sources closely mirrors data on fertilizer application with particularly large N{sub 2}O sources over the US Cornbelt. Existing inventories for N{sub 2}O predict emissions that differ substantially from the inverse model results in both seasonal cycle and magnitude. We estimate a total annual N{sub 2}O budget over the central US of 0.9-1.2 TgN/yr and an extrapolated budget for the entire US and Canada of 2.1-2.6 TgN/yr. By this estimate, the US and Canada account for 12-15% of the total global N{sub 2}O source or 32-39% of the global anthropogenic source as reported by the Intergovernmental Panel on Climate Change in 2007.

  20. Scenario Evaluation and Regionalization Analysis (SERA) Model

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 <Department ofDepartment| DepartmentScale Models andScenario

  1. PHARAO Laser Source Flight Model: Design and Performances

    E-Print Network [OSTI]

    Lévèque, Thomas; Esnault, François-Xavier; Delaroche, Christophe; Massonnet, Didier; Grosjean, Olivier; Buffe, Fabrice; Torresi, Patrizia; Bomer, Thierry; Pichon, Alexandre; Béraud, Pascal; Lelay, Jean-Pierre; Thomin, Stéphane; Laurent, Philippe

    2015-01-01T23:59:59.000Z

    In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

  2. The morphology of the emission line region of Compact Steep Spectrum radio sources

    E-Print Network [OSTI]

    D. J. Axon; A. Capetti; R. Fanti; R. Morganti; A. Robinson; R. Spencer

    2000-06-26T23:59:59.000Z

    We present the results of HST narrow band imaging of eleven Compact Steep Spectrum (CSS) radio sources. Five of them (3C 48, 3C 147, 3C303.1, 3C 277.1 and 4C 12.50) were part of a dedicated ``pointed'' program of deep line imaging ([OIII]). For six additional sources (3C 49, 3C 93.1, 3C 138, 3C 268.3, 3C305.1 and 3C343.1) ``snapshot'' images ([OIII] or [OII]) were taken from the HST archive. In all but one of the targets (3C 49) line emission has been detected and only in one case (3C 138) is unresolved. In four out five of the sources with deep observations, the line emission extends well beyond the size of the radio source but along the radio axis. Structures of similar surface brightness would have not been seen in the snapshot images. These emission line structures extend to scales of 10 to 30 kpc and cover a projected angle, when seen from the nucleus, of 30 to 110 degrees, indicating that the nuclear illumination is anisotropic. Photon counting arguments also support this interpretation. In six objects the radio emission extends over more than 1 arcsec. In these cases the line emission has an elongated structure, linking the nucleus to the radio-lobes, possibly tracing the path of the invisible radio jets. Nevertheless the emission line morphologies do not show the bow shocks at the extremities of the radio lobes expected if they are sources whose expansion is frustrated by a dense external medium. Our data favour the alternative model in which CSSs are the young phase of the large size radio sources. When ``pointed'' pure continuum images are available, there appears to be no alignment between radio and continuum emission which contradicts previous suggestions based on broad-band HST imaging.

  3. Source Scaling of Single-Fired and Delay-Fired Explosions Constrained by In-Mine and Regional Seismograms

    E-Print Network [OSTI]

    Stump, Brian W.

    Source Scaling of Single-Fired and Delay-Fired Explosions Constrained by In-Mine and Regional (simultaneously detonated) explosions observed in the mine and at regional distances. These single-fired (360 km) using a seismic array near Pinedale, Wyoming (PDAR). The single-fired explosions ranged

  4. A regional model coupling with OASIS3-MCT

    E-Print Network [OSTI]

    A regional model coupling with OASIS3-MCT Eric Maisonnave WN/CMGC/13/34 #12;Table of Contents of an OASIS3-MCT based coupled model must be set up providing input informations (grid definition.base.define_clm_limits ), reducing to 1 the number of sub-domain dedicated to DATM, OASIS interpolates the COSMO domain limits

  5. Models of radiofrequency coupling for negative ion sources

    SciTech Connect (OSTI)

    Cavenago, M.; Petrenko, S. [INFN-LNL, viale dell'Universita n.2, 35020 Legnaro (Italy)

    2012-02-15T23:59:59.000Z

    Radiofrequency heating for ICP (inductively coupled plasma) ion sources depends on the source operating pressure, the presence or absence of a Faraday shield, the driver coil geometry, the frequency used, and the magnetic field configuration: in negative ion source a magnetic filter seems necessary for H{sup -} survival. The result of single particle simulations showing the possibility of electron acceleration in the preglow regime and for reasonable driver chamber radius (15 cm) is reported, also as a function of the static external magnetic field. An effective plasma conductivity, depending not only from electron density, temperature, and rf field but also on static magnetic field is here presented and compared to previous models. Use of this conductivity and of multiphysics tools for a plasma transport and heating model is shown and discussed for a small source.

  6. Regional Climate Model Projections for the State of Washington

    SciTech Connect (OSTI)

    Salathe, E.; Leung, Lai-Yung R.; Qian, Yun; Zhang, Yongxin

    2010-05-05T23:59:59.000Z

    Global climate models do not have sufficient spatial resolution to represent the atmospheric and land surface processes that determine the unique regional heterogeneity of the climate of the State of Washington. If future large-scale weather patterns interact differently with the local terrain and coastlines than current weather patterns, local changes in temperature and precipitation could be quite different from the coarse-scale changes projected by global models. Regional climate models explicitly simulate the interactions between the large-scale weather patterns simulated by a global model and the local terrain. We have performed two 100-year climate simulations using the Weather and Research Forecasting (WRF) model developed at the National Center for Atmospheric Research (NCAR). One simulation is forced by the NCAR Community Climate System Model version 3 (CCSM3) and the second is forced by a simulation of the Max Plank Institute, Hamburg, global model (ECHAM5). The mesoscale simulations produce regional changes in snow cover, cloudiness, and circulation patterns associated with interactions between the large-scale climate change and the regional topography and land-water contrasts. These changes substantially alter the temperature and precipitation trends over the region relative to the global model result or statistical downscaling. To illustrate this effect, we analyze the changes from the current climate (1970-1999) to the mid 21st century (2030-2059). Changes in seasonal-mean temperature, precipitation, and snowpack are presented. Several climatological indices of extreme daily weather are also presented: precipitation intensity, fraction of precipitation occurring in extreme daily events, heat wave frequency, growing season length, and frequency of warm nights. Despite somewhat different changes in seasonal precipitation and temperature from the two regional simulations, consistent results for changes in snowpack and extreme precipitation are found in both simulations.

  7. IMPULSIVE ACCELERATION OF CORONAL MASS EJECTIONS. I. STATISTICS AND CORONAL MASS EJECTION SOURCE REGION CHARACTERISTICS

    SciTech Connect (OSTI)

    Bein, B. M.; Berkebile-Stoiser, S.; Veronig, A. M.; Temmer, M.; Muhr, N.; Kienreich, I.; Utz, D. [IGAM/Institute of Physics, University of Graz, Universitaetsplatz 5, 8010 Graz (Austria); Vrsnak, B. [Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb (Croatia)

    2011-09-10T23:59:59.000Z

    We use high time cadence images acquired by the STEREO EUVI and COR instruments to study the evolution of coronal mass ejections (CMEs) from their initiation through impulsive acceleration to the propagation phase. For a set of 95 CMEs we derived detailed height, velocity, and acceleration profiles and statistically analyzed characteristic CME parameters: peak acceleration, peak velocity, acceleration duration, initiation height, height at peak velocity, height at peak acceleration, and size of the CME source region. The CME peak accelerations we derived range from 20 to 6800 m s{sup -2} and are inversely correlated with the acceleration duration and the height at peak acceleration. Seventy-four percent of the events reach their peak acceleration at heights below 0.5 R{sub sun}. CMEs that originate from compact sources low in the corona are more impulsive and reach higher peak accelerations at smaller heights. These findings can be explained by the Lorentz force, which drives the CME accelerations and decreases with height and CME size.

  8. Network infection source identification under the SIRI model

    E-Print Network [OSTI]

    Hu, Wuhua; Harilal, Athul; Xiao, Gaoxi

    2014-01-01T23:59:59.000Z

    We study the problem of identifying a single infection source in a network under the susceptible-infected-recovered-infected (SIRI) model. We describe the infection model via a state-space model, and utilizing a state propagation approach, we derive an algorithm based on dynamic message passing (DMP), which we call DMP+, to infer the infection source. The DMP+ algorithm uses the partial or complete observations of node states at a particular time, where the elapsed time from the start of the infection is unknown. It is able to incorporate side information (if any) of the observed states of a subset of nodes at different times, and of the prior probability of each infected or recovered node to be the infection source. Simulation results suggest that the DMP+ estimator outperforms the DMP and Jordan center estimators over a wide range of infection and reinfection rates.

  9. ar-mog source model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Multi Laskey, Kathryn Blackmond 30 A COMPOSITE SOURCE MODEL WITH FRACTAL SUBEVENT SIZE DISTRIBUTION Geosciences Websites Summary: A COMPOSITE SOURCE MODEL WITH FRACTAL...

  10. Estimates of the absorbed fraction of energy for various electron source and target regions in the upper respiratory tract 

    E-Print Network [OSTI]

    Calvo, Sebastian

    1994-01-01T23:59:59.000Z

    . ACKNOWLEDGMENTS The author would like to thank committee members Drs. Wesley Bolch and John Poston of thc Nuclear Engineering Department, Dr. Keith Eckerman of the Oak Ridge National Laboratory and the Nuclear Engineering Department, and Dr. Michael Walker... INFORMATION MATERIALS AND METHODS . The Model Used in This Study EGS4 Code RESULTS . Source in Tracheal Airway Source on Tracheal Airway Surface Source on Carinal Ridge Surface Source in Airways of Main Bronchi and Bifurcation Zone DISCUSSION...

  11. KAPPA DISTRIBUTION MODEL FOR HARD X-RAY CORONAL SOURCES OF SOLAR FLARES

    SciTech Connect (OSTI)

    Oka, M.; Ishikawa, S.; Saint-Hilaire, P.; Krucker, S.; Lin, R. P. [Space Sciences Laboratory, University of California Berkeley (United States)] [Space Sciences Laboratory, University of California Berkeley (United States)

    2013-02-10T23:59:59.000Z

    Solar flares produce hard X-ray emission, the photon spectrum of which is often represented by a combination of thermal and power-law distributions. However, the estimates of the number and total energy of non-thermal electrons are sensitive to the determination of the power-law cutoff energy. Here, we revisit an 'above-the-loop' coronal source observed by RHESSI on 2007 December 31 and show that a kappa distribution model can also be used to fit its spectrum. Because the kappa distribution has a Maxwellian-like core in addition to a high-energy power-law tail, the emission measure and temperature of the instantaneous electrons can be derived without assuming the cutoff energy. Moreover, the non-thermal fractions of electron number/energy densities can be uniquely estimated because they are functions of only the power-law index. With the kappa distribution model, we estimated that the total electron density of the coronal source region was {approx}2.4 Multiplication-Sign 10{sup 10} cm{sup -3}. We also estimated without assuming the source volume that a moderate fraction ({approx}20%) of electrons in the source region was non-thermal and carried {approx}52% of the total electron energy. The temperature was 28 MK, and the power-law index {delta} of the electron density distribution was -4.3. These results are compared to the conventional power-law models with and without a thermal core component.

  12. Modeling-Computer Simulations At U.S. West Region (Williams ...

    Open Energy Info (EERE)

    Modeling-Computer Simulations At U.S. West Region (Williams & Deangelo, 2008) Exploration Activity Details Location U.S. West Region Exploration Technique Modeling-Computer...

  13. Regional Economic Models, Inc. (REMI) Model | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ | Roadmap Jump to:bJumpRedSeismic Imaging,WesternRegional

  14. THE DEVELOPMENT MODEL ELECTRONIC COMMERCE OF REGIONAL AGRICULTURE

    E-Print Network [OSTI]

    Boyer, Edmond

    THE DEVELOPMENT MODEL ELECTRONIC COMMERCE OF REGIONAL AGRICULTURE Jun Kang* , Lecai Cai, Hongchan, Fax: +86-813-5505966, Email: kj_sky@126.com Abstract: With the developing of the agricultural information, it is inevitable trend of the development of agricultural electronic commercial affairs

  15. Reference wind farm selection for regional wind power prediction models

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Reference wind farm selection for regional wind power prediction models Nils Siebert George.siebert@ensmp.fr, georges.kariniotakis@ensmp.fr Abstract Short-term wind power forecasting is recognized today as a major requirement for a secure and economic integration of wind generation in power systems. This paper deals

  16. A SPATIAL WEB GRAPH MODEL WITH LOCAL INFLUENCE REGIONS

    E-Print Network [OSTI]

    Pralat, Pawel

    mining technique, web pages are often represented as vectors in a word-document space. Using LatentA SPATIAL WEB GRAPH MODEL WITH LOCAL INFLUENCE REGIONS W. AIELLO, A. BONATO, C. COOPER, J. JANSSEN-degree distribution, with exponent in [2, ) depending on the parameters, and with concentration for a wide range of in

  17. CHALLENGES IN SOURCE TERM MODELING OF DECONTAMINATION AND DECOMMISSIONING WASTES.

    SciTech Connect (OSTI)

    SULLIVAN, T.M.

    2006-08-01T23:59:59.000Z

    Development of real-time predictive modeling to identify the dispersion and/or source(s) of airborne weapons of mass destruction including chemical, biological, radiological, and nuclear material in urban environments is needed to improve response to potential releases of these materials via either terrorist or accidental means. These models will also prove useful in defining airborne pollution dispersion in urban environments for pollution management/abatement programs. Predicting gas flow in an urban setting on a scale of less than a few kilometers is a complicated and challenging task due to the irregular flow paths that occur along streets and alleys and around buildings of different sizes and shapes, i.e., ''urban canyons''. In addition, air exchange between the outside and buildings and subway areas further complicate the situation. Transport models that are used to predict dispersion of WMD/CBRN materials or to back track the source of the release require high-density data and need defensible parameterizations of urban processes. Errors in the data or any of the parameter inputs or assumptions will lead to misidentification of the airborne spread or source release location(s). The need for these models to provide output in a real-time fashion if they are to be useful for emergency response provides another challenge. To improve the ability of New York City's (NYC's) emergency management teams and first response personnel to protect the public during releases of hazardous materials, the New York City Urban Dispersion Program (UDP) has been initiated. This is a four year research program being conducted from 2004 through 2007. This paper will discuss ground level and subway Perfluorocarbon tracer (PFT) release studies conducted in New York City. The studies released multiple tracers to study ground level and vertical transport of contaminants. This paper will discuss the results from these tests and how these results can be used for improving transport models needed for risk assessment.

  18. Power Transmission From The ITER Model Negative Ion Source

    SciTech Connect (OSTI)

    Boilson, D. [Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland); Esch, H. P. L. de; Grand, C.; Hemsworth, R. S.; Krylov, A. [Association EURATOM-CEA, CEA/DSM/DRFC, CEA-Cadarache, 13108 St Paul-Lez-Durance (France)

    2007-08-10T23:59:59.000Z

    In Cadarache development on negative ion sources is being carried out on the KAMABOKO III ion source on the MANTIS test bed. This is a model of the ion source designed for the neutral beam injectors of ITER. This ion source has been developed in collaboration with JAERI, Japan, who also designed and supplied the ion source. Its target performance is to accelerate a D- beam, with a current density of 200 A/m2 and <1 electron extracted per accelerated D- ion, at a source filling pressure of 0.3 Pa. For ITER a continuous ion beam must be assured for pulse lengths of 1000 s, but beams of up to 3,600 s are also envisaged. The ion source is attached to a 3 grid 30 keV accelerator (also supplied by JAERI) and the accelerated negative ion current is determined from the energy deposited on a calorimeter. During long pulse operation ({<=}1000 s) it was found that the current density of both D- and H- beams, measured at the calorimeter was lower than expected and that a large discrepancy existed between the accelerated currents measured electrically and those transmitted to the calorimeter. The possibility that this discrepancy arose because the accelerated current included electrons (which would not be able to reach the calorimeter) was investigated and subsequently eliminated. Further studies have shown that the fraction of the electrical current reaching the calorimeter varies with the pulse length, which led to the suggestion that one or more of the accelerator grids were distorting due to the incident power during operation, leading to a progressive deterioration in the beam quality.. New extraction and acceleration grids have been designed and installed, which should have a better tolerance to thermal loads than those previously used. This paper describes the measurements of the power transmission and distribution using these grids.

  19. Regional-Scale Climate Change: Observations and Model Simulations

    SciTech Connect (OSTI)

    Raymond S. Bradley; Henry F. Diaz

    2010-12-14T23:59:59.000Z

    This collaborative proposal addressed key issues in understanding the Earthâ??s climate system, as highlighted by the U.S. Climate Science Program. The research focused on documenting past climatic changes and on assessing future climatic changes based on suites of global and regional climate models. Geographically, our emphasis was on the mountainous regions of the world, with a particular focus on the Neotropics of Central America and the Hawaiian Islands. Mountain regions are zones where large variations in ecosystems occur due to the strong climate zonation forced by the topography. These areas are particularly susceptible to changes in critical ecological thresholds, and we conducted studies of changes in phonological indicators based on various climatic thresholds.

  20. PSCAD/EMTDC-Based Modeling and Analysis of a Microgrid with Renewable Energy Sources

    E-Print Network [OSTI]

    Chu, Zhengguo

    2010-07-14T23:59:59.000Z

    . The proposed microgrid system includes fundamental power system component models, two renewable energy source models (wind and solar) and one energy storage source model. Different case studies were conducted. The results from the simulation case studies...

  1. PSCAD/EMTDC-Based Modeling and Analysis of a Microgrid with Renewable Energy Sources 

    E-Print Network [OSTI]

    Chu, Zhengguo

    2010-07-14T23:59:59.000Z

    . The proposed microgrid system includes fundamental power system component models, two renewable energy source models (wind and solar) and one energy storage source model. Different case studies were conducted. The results from the simulation case studies...

  2. Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France and

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France Introduction Renewable energy sources such as biomass and biofuels are increasingly being seen as important of biofuels on the final consumption of energy in transport should be 10%. The long-term target is to reduce

  3. Operation and Thermal Modeling of the ISIS H– Source from 50 to 2 Hz Repetition Rates

    E-Print Network [OSTI]

    Pereira, H; Lettry, J

    2013-01-01T23:59:59.000Z

    CERN’s Linac4 accelerator H? ion source, currently under construction, will operate at a 2 Hz repetition rate, with pulse length of 0.5 ms and a beam current of 80 mA. Its reliability must exceed 99 % with a mandatory 3 month uninterrupted operation period. A Penning ion source is successfully operated at ISIS; at 50 Hz repetition rate it reliably provides 55 mA H? pulses of 0.25 ms duration over 1 month. The discharge plasma ignition is very sensitive to the temperatures of the discharge region, especially of its cathode. The investigation by modeling and measurement of operation parameters suitable for arc ignition and H? production at 2 Hz is of paramount importance and must be understood prior to the implementation of discharge ion sources in the Linac4 accelerator. In its original configuration, the ISIS H? source delivers beam only if the repetition rate is above 12.5 Hz, this paper describes the implementation of a temperature control of the discharge region aiming at lower repetition rate op...

  4. California Wintertime Precipitation in Regional and Global Climate Models

    SciTech Connect (OSTI)

    Caldwell, P M

    2009-04-27T23:59:59.000Z

    In this paper, wintertime precipitation from a variety of observational datasets, regional climate models (RCMs), and general circulation models (GCMs) is averaged over the state of California (CA) and compared. Several averaging methodologies are considered and all are found to give similar values when model grid spacing is less than 3{sup o}. This suggests that CA is a reasonable size for regional intercomparisons using modern GCMs. Results show that reanalysis-forced RCMs tend to significantly overpredict CA precipitation. This appears to be due mainly to overprediction of extreme events; RCM precipitation frequency is generally underpredicted. Overprediction is also reflected in wintertime precipitation variability, which tends to be too high for RCMs on both daily and interannual scales. Wintertime precipitation in most (but not all) GCMs is underestimated. This is in contrast to previous studies based on global blended gauge/satellite observations which are shown here to underestimate precipitation relative to higher-resolution gauge-only datasets. Several GCMs provide reasonable daily precipitation distributions, a trait which doesn't seem tied to model resolution. GCM daily and interannual variability is generally underpredicted.

  5. Depth and mineralogy of the magma source or pause region for the Carboniferous Liberty Hill pluton, South Carolina

    SciTech Connect (OSTI)

    Speer, J.A.

    1988-06-01T23:59:59.000Z

    Use of Al content geobarometry on clinopyroxene inclusions in plagioclase from the Carboniferous Liberty Hill pluton, South Carolina, yields pressure estimates of 8-10 kbar. Amphibole crystallization pressures are 3.1-4.7 kbar; contact metamorphic pressure are 4.5 kbar. Clinopyroxenes could be early crystallization products from the melt, restite crystals from the source region, xenocrysts from the magma conduit walls, or xenocrysts from a more mafic magma. Compositional uniformity of granitoid clinopyroxenes but dissimilarity with those in contemporaneous gabbroids is evidence against a xenocrystic origin. The deeper depths are interpreted as either the source region or a pausing place important in the crystallization history of the magma during its ascent to the upper crust. Early crystallization assemblage of the granitoid, and possibly the assemblage of the source region, was amphibole + clinopyroxene +/- plagioclase-bearing. An amphibolitic lower crustal source is consistent with the Sr and O isotopic and rare-earth-element studies of this and many other similar-age granitoids in the southern Appalachians.

  6. Spatial structure of electric potential near the extraction region in Cs-seeded H{sup -} ion sources

    SciTech Connect (OSTI)

    Fukano, A.; Hanatani, J.; Matsumiya, T.; Hatayama, A. [Mechanical Sysytems Engineering Course, Monozukuri Department, Tokyo Metropolitan College of Industrial Technology, Higashioi, Shinagawa, Tokyo 140-0011 (Japan); Faculty of Science and Technology, Keio University, Hiyoshi, Yokohama 223-8522 (Japan)

    2008-02-15T23:59:59.000Z

    Structure of electric potential near the extraction region in a negative ion source is investigated analytically with the effect of strong surface H{sup -} production. The potential profile is analyzed one dimensional by solving the plasma-sheath equation, which gives the electric potential in the plasma region and the sheath region near the wall self-consistently. The potential profile depends on the production rate and the temperature of negative ions. As the production rate becomes large and the negative ion energy becomes small, the potential near the extraction region decreases. The negative potential peak is formed near the plasma grid (PG) surface for the case of large amount and low energy surface production. As a result, negative ions are reflected by this negative potential peak near the PG and returned to the PG surface. This reflection mechanism by the negative potential peak possibly affects the negative ion extraction.

  7. Groundwater Nitrogen Source Identification and Remediation in the Texas High Plains and Rolling Plains Regions

    E-Print Network [OSTI]

    Delaune, P.; Scanlon, B.; Reedy, R.; Schwartz, R.; Baumhardt, L.; Gregory, L.

    2013-01-01T23:59:59.000Z

    data on potential management strategies that can remediate groundwater nitrate levels, this project was developed. The primary objective was to identify sources of groundwater nitrate in the Texas High Plains and Rolling Plains and the secondary...

  8. SOURCE?

    Energy Savers [EERE]

    Department of Energy (DOE) in partnership with Lawrence Berkeley National Laboratory (LBNL), is an open-source code package designed to be a common, low-cost, standardized tool...

  9. Source Contributions to VOC's to Ozone Formation in Southeast Texas Using a Source-oriented Air Quality Model 

    E-Print Network [OSTI]

    Krishnan, Anupama

    2011-08-08T23:59:59.000Z

    Houston-Galveston-Brazoria area is in severe non-attainment status for ozone compliance. Source-oriented mechanistic modeling was used to determine the major sources of VOCs that contributes to ozone formation during the Texas Air Quality Study (Tex...

  10. Source Contributions to VOC's to Ozone Formation in Southeast Texas Using a Source-oriented Air Quality Model

    E-Print Network [OSTI]

    Krishnan, Anupama

    2011-08-08T23:59:59.000Z

    Houston-Galveston-Brazoria area is in severe non-attainment status for ozone compliance. Source-oriented mechanistic modeling was used to determine the major sources of VOCs that contributes to ozone formation during the Texas Air Quality Study (Tex...

  11. Discrepancies in the prediction of solar wind using potential field source surface model: An investigation of possible sources

    E-Print Network [OSTI]

    California at Berkeley, University of

    Discrepancies in the prediction of solar wind using potential field source surface model expansion factor (FTE) at the source surface and the solar wind speed (SWS) observed at Earth, which has been made use of in the prediction of solar wind speed near the Earth with reasonable accuracy. However

  12. Regionalization of subsurface stormflow parameters of hydrologic models: Derivation from regional analysis of streamflow recession curves

    SciTech Connect (OSTI)

    Ye, Sheng; Li, Hongyi; Huang, Maoyi; Ali, Melkamu; Leng, Guoyong; Leung, Lai-Yung R.; Wang, Shaowen; Sivapalan, Murugesu

    2014-07-21T23:59:59.000Z

    Subsurface stormflow is an important component of the rainfall–runoff response, especially in steep terrain. Its contribution to total runoff is, however, poorly represented in the current generation of land surface models. The lack of physical basis of these common parameterizations precludes a priori estimation of the stormflow (i.e. without calibration), which is a major drawback for prediction in ungauged basins, or for use in global land surface models. This paper is aimed at deriving regionalized parameterizations of the storage–discharge relationship relating to subsurface stormflow from a top–down empirical data analysis of streamflow recession curves extracted from 50 eastern United States catchments. Detailed regression analyses were performed between parameters of the empirical storage–discharge relationships and the controlling climate, soil and topographic characteristics. The regression analyses performed on empirical recession curves at catchment scale indicated that the coefficient of the power-law form storage–discharge relationship is closely related to the catchment hydrologic characteristics, which is consistent with the hydraulic theory derived mainly at the hillslope scale. As for the exponent, besides the role of field scale soil hydraulic properties as suggested by hydraulic theory, it is found to be more strongly affected by climate (aridity) at the catchment scale. At a fundamental level these results point to the need for more detailed exploration of the co-dependence of soil, vegetation and topography with climate.

  13. Information-Theoretic Key Agreement of Multiple Terminals -Part I: Source Model

    E-Print Network [OSTI]

    Anantharam, Venkat

    1 Information-Theoretic Key Agreement of Multiple Terminals - Part I: Source Model Amin Aminzadeh the widely studied source model. In the source model the terminals wishing to generate a secret key, as well of jointly distributed random variables, after which the terminals are allowed interactive authenticated

  14. North American Carbon Program (NACP) Regional Interim Synthesis: Terrestrial Biospheric Model Intercomparision

    SciTech Connect (OSTI)

    Huntzinger, Deborah [University of Michigan; Post, Wilfred M [ORNL; Michalak, Anna [University of Michigan; West, Tristram O. [Joint Global Change Research Institute, PNNL; Jacobson, Andrew [NOAA ESRL and CIRES; Baker, Ian [Colorado State University, Fort Collins; Chen, Jing M. [University of Toronto; Davis, Kenneth [Pennsylvania State University; Hayes, Daniel J [ORNL; Hoffman, Forrest M [ORNL; Jain, Atul [University of Illinois, Urbana-Champaign; Liu, Shuguang [United States Geological Survey, Center for Earth Resources Observation and Science (USGS EROS); Mcguire, David [University of Alaska; Neilson, Ronald [Oregon State University, Corvallis; Poulter, Ben [Potsdam Institute for Climate Impact Research, Potsdam, Germany; Tian, Hanqin [Auburn University, Auburn, Alabama; Thornton, Peter E [ORNL; Tomelleri, Enrico [Max Planck Institute for Biogeochemistry; Viovy, Nicolas [National Center for Scientific Research, Gif-sur-Yvette, France; Xiao, Jingfeng [Purdue University; Cook, Robert B [ORNL

    2012-01-01T23:59:59.000Z

    Understanding of carbon exchange between terrestrial ecosystems and the atmosphere can be improved through direct observations and experiments, as well as through modeling activities. Terrestrial biosphere models (TBMs) have become an integral tool for extrapolating local observations and understanding to much larger terrestrial regions. Although models vary in their specific goals and approaches, their central role within carbon cycle science is to provide a better understanding of the mechanisms currently controlling carbon exchange. Recently, the North American Carbon Program (NACP) organized several interim-synthesis activities to evaluate and inter-compare models and observations at local to continental scales for the years 2000-2005. Here, we compare the results from the TBMs collected as part of the regional and continental interim-synthesis (RCIS) activities. The primary objective of this work is to synthesize and compare the 19 participating TBMs to assess current understanding of the terrestrial carbon cycle in North America. Thus, the RCIS focuses on model simulations available from analyses that have been completed by ongoing NACP projects and other recently published studies. The TBM flux estimates are compared and evaluated over different spatial (1{sup o} x 1{sup o} and spatially aggregated to different regions) and temporal (monthly and annually) scales. The range in model estimates of net ecosystem productivity (NEP) for North America is much narrower than estimates of productivity or respiration, with estimates of NEP varying between -0.7 and 2.2 PgC yr{sup -1}, while gross primary productivity and heterotrophic respiration vary between 12.2 and 32.9 PgC yr{sup -1} and 5.6 and 13.2 PgC yr{sup -1}, respectively. The range in estimates from the models appears to be driven by a combination of factors, including the representation of photosynthesis, the source and of environmental driver data and the temporal variability of those data, as well as whether nutrient limitation is considered in soil carbon decomposition. The disagreement in current estimates of carbon flux across North America, including whether North America is a net biospheric carbon source or sink, highlights the need for further analysis through the use of model runs following a common simulation protocol, in order to isolate the influences of model formulation, structure, and assumptions on flux estimates.

  15. Improving the Simulation of the West African Monsoon Using the MIT Regional Climate Model

    E-Print Network [OSTI]

    Im, Eun-Soon

    This paper presents an evaluation of the performance of the Massachusetts Institute of Technology (MIT) regional climate model (MRCM) in simulating the West African monsoon. The MRCM is built on the Regional Climate Model, ...

  16. Improvement of snowpack simulations in a regional climate model

    SciTech Connect (OSTI)

    Jin, J.; Miller, N.L.

    2011-01-10T23:59:59.000Z

    To improve simulations of regional-scale snow processes and related cold-season hydroclimate, the Community Land Model version 3 (CLM3), developed by the National Center for Atmospheric Research (NCAR), was coupled with the Pennsylvania State University/NCAR fifth-generation Mesoscale Model (MM5). CLM3 physically describes the mass and heat transfer within the snowpack using five snow layers that include liquid water and solid ice. The coupled MM5–CLM3 model performance was evaluated for the snowmelt season in the Columbia River Basin in the Pacific Northwestern United States using gridded temperature and precipitation observations, along with station observations. The results from MM5–CLM3 show a significant improvement in the SWE simulation, which has been underestimated in the original version of MM5 coupled with the Noah land-surface model. One important cause for the underestimated SWE in Noah is its unrealistic land-surface structure configuration where vegetation, snow and the topsoil layer are blended when snow is present. This study demonstrates the importance of the sheltering effects of the forest canopy on snow surface energy budgets, which is included in CLM3. Such effects are further seen in the simulations of surface air temperature and precipitation in regional weather and climate models such as MM5. In addition, the snow-season surface albedo overestimated by MM5–Noah is now more accurately predicted by MM5–CLM3 using a more realistic albedo algorithm that intensifies the solar radiation absorption on the land surface, reducing the strong near-surface cold bias in MM5–Noah. The cold bias is further alleviated due to a slower snowmelt rate in MM5–CLM3 during the early snowmelt stage, which is closer to observations than the comparable components of MM5–Noah. In addition, the over-predicted precipitation in the Pacific Northwest as shown in MM5–Noah is significantly decreased in MM5 CLM3 due to the lower evaporation resulting from the longer snow duration.

  17. Sources and Pathways of Nutrients in the Semi-Arid Region of Beijing-Tianjin, China

    E-Print Network [OSTI]

    Wehrli, Bernhard

    to eutrophication, which causes immense ecological and economic problems. One region that is in transition eutrophication and even more rapidly than was previously observed in Europe. INTRODUCTION Eutrophication. In the western world, research on the mitigation of eutrophication conducted from the 1970 to the 1990s

  18. A Global, Multi-Resolution Approach to Regional Ocean Modeling

    SciTech Connect (OSTI)

    Du, Qiang

    2013-11-08T23:59:59.000Z

    In this collaborative research project between Pennsylvania State University, Colorado State University and Florida State University, we mainly focused on developing multi-resolution algorithms which are suitable to regional ocean modeling. We developed hybrid implicit and explicit adaptive multirate time integration method to solve systems of time-dependent equations that present two signi#12;cantly di#11;erent scales. We studied the e#11;ects of spatial simplicial meshes on the stability and the conditioning of fully discrete approximations. We also studies adaptive #12;nite element method (AFEM) based upon the Centroidal Voronoi Tessellation (CVT) and superconvergent gradient recovery. Some of these techniques are now being used by geoscientists(such as those at LANL).

  19. Modeling Dynamics in the Central Regions of Disk Galaxies

    E-Print Network [OSTI]

    Isaac Shlosman

    2004-12-07T23:59:59.000Z

    The central regions of disk galaxies are hosts to supermassive black holes whose masses show a tight correlation with the properties of surrounding stellar bulges. While the exact origin of this dependency is not clear, it can be related to the very basic properties of dark matter halos and the associated gas and stellar dynamics in the central kpc of host galaxies. In this review we discuss some of the recent developments in modeling the wide spectrum of dynamical processes which can be affiliated with the above phenomena, such as the structure of molecular tori in AGN, structure formation in triaxial halos, and dissipative and non-dissipative dynamics in nested bar systems, with a particular emphasis on decoupling of gaseous nuclear bars. We also briefly touch on the subject of fueling the nuclear starbursts and AGN.

  20. Heterogeneous Chemistry of Individual Mineral Dust Particles from Different Dust Source Regions: The Importance of Particle Mineralogy

    SciTech Connect (OSTI)

    Krueger, Brenda J.; Grassian, Vicki H.; Cowin, James P.; Laskin, Alexander

    2004-11-01T23:59:59.000Z

    The heterogeneous chemistry of individual dust particles from four different dust source regions is investigated on a particle-by-particle basis using state-of-the-art scanning electron microscopy techniques including computer-controlled scanning electron microscopy/computer-controlled X-ray analysis (CCSEM/EDX). Morphology and compositional changes of individual particles as they react with nitric acid are observed. Clear differences in the reactivity of mineral dusts from these four different dust regions with nitric acid could be observed. Mineral dust from source regions containing high levels of calcium, such as those found in parts of China and Saudi Arabia, are found to react to the greatest extent. Calcium containing minerals, such as calcite (CaCO3) and dolomite (CaMg(CO3)2), react to form nitrate salt whereas other calcium containing minerals such as gypsum (CaSO4?2H2O) do not react. The importance of particle chemical composition and mineralogy in the heterogeneous chemistry of mineral dust aerosols is definitively borne out in this study of individual dust particles.

  1. Modeling preferential water flow and solute transport in unsaturated soil using the active region model

    SciTech Connect (OSTI)

    Sheng, F.; Wang, K.; Zhang, R.; Liu, H.H.

    2009-03-15T23:59:59.000Z

    Preferential flow and solute transport are common processes in the unsaturated soil, in which distributions of soil water content and solute concentrations are often characterized as fractal patterns. An active region model (ARM) was recently proposed to describe the preferential flow and transport patterns. In this study, ARM governing equations were derived to model the preferential soil water flow and solute transport processes. To evaluate the ARM equations, dye infiltration experiments were conducted, in which distributions of soil water content and Cl{sup -} concentration were measured. Predicted results using the ARM and the mobile-immobile region model (MIM) were compared with the measured distributions of soil water content and Cl{sup -} concentration. Although both the ARM and the MIM are two-region models, they are fundamental different in terms of treatments of the flow region. The models were evaluated based on the modeling efficiency (ME). The MIM provided relatively poor prediction results of the preferential flow and transport with negative ME values or positive ME values less than 0.4. On the contrary, predicted distributions of soil water content and Cl- concentration using the ARM agreed reasonably well with the experimental data with ME values higher than 0.8. The results indicated that the ARM successfully captured the macroscopic behavior of preferential flow and solute transport in the unsaturated soil.

  2. Future regional climate change in the ten hydrologic regions of California: A climate modeling investigation

    E-Print Network [OSTI]

    Sloan, Lisa C

    2005-01-01T23:59:59.000Z

    snow accumulation (mm snow water equivalent) by region.Bell, J.L. , Jour. American Water Resources Assoc. , 591-CO, 1993. Department of Water Resources (DWR), California

  3. Development of a criteria based strategic sourcing model

    E-Print Network [OSTI]

    Quiñonez, Carlo G. (Carlo Gabriel)

    2013-01-01T23:59:59.000Z

    Strategic sourcing is a key factor in enhancing Nike's competitiveness and organizational and operational performances. As Nike faces increasing pressure to expand margins and reduce source base risk during a climate of ...

  4. Bilinear estimation of pollution source profiles in receptor models

    E-Print Network [OSTI]

    Washington at Seattle, University of

    the pollution sources based on air pollution data. This article is concerned with estimation of the source and assess the contribution of each source based on this data. There have been two traditional approaches. Los Angeles, CA 90089-2531 + Address for correspondence: NRCSE, University of Washington, Box 351720

  5. SOURCE REGIONS OF THE INTERPLANETARY MAGNETIC FIELD AND VARIABILITY IN HEAVY-ION ELEMENTAL COMPOSITION IN GRADUAL SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect (OSTI)

    Ko, Yuan-Kuen; Wang, Yi-Ming [Space Science Division, Naval Research Laboratory, Code 7680, Washington, DC 20375 (United States); Tylka, Allan J. [NASA Goddard Space Flight Center, Code 672, Greenbelt, MD 20771 (United States); Ng, Chee K. [College of Science, George Mason University, Fairfax, VA 22030 (United States); Dietrich, William F., E-mail: yko@ssd5.nrl.navy.mil [Praxis, Inc., Alexandria, VA 22303 (United States)

    2013-10-20T23:59:59.000Z

    Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. However, an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the potential-field source-surface model to map the Sun-L1 interplanetary magnetic field (IMF) line back to its source region on the Sun at the time of the SEP observations and (2) then look for a correlation between SEP composition (as measured by Wind and Advanced Composition Explorer at ?2-30 MeV nucleon{sup –1}) and characteristics of the identified IMF source regions. The study is based on 24 SEP events, identified as a statistically significant increase in ?20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly emergent solar magnetic flux and CMEs was lower than in solar-maximum years, and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF source, with the largest enhancements occurring when the footpoint field is strong due to the nearby presence of an active region (AR). In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering (at least on average), similar to that found in impulsive events. Such results lead us to suggest that magnetic reconnection in footpoint regions near ARs bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.

  6. R i l P tf li M d lRegional Portfolio Model Software Redevelopment

    E-Print Network [OSTI]

    R i l P tf li M d lRegional Portfolio Model Software Redevelopment Request for Proposals #12;II. Services Desired by the CouncilII. Services Desired by the Council Software redevelopment of the Council's Regional Software redevelopment of the Council s Regional Portfolio Model (RPM) Redeveloped

  7. Regional Impact of an Elevated Heat Source: The Zagros Plateau of Iran BENJAMIN F. ZAITCHIK, JASON P. EVANS, AND RONALD B. SMITH

    E-Print Network [OSTI]

    Evans, Jason

    Regional Impact of an Elevated Heat Source: The Zagros Plateau of Iran BENJAMIN F. ZAITCHIK, JASON in the north, the Taurus Moun- tains of Turkey, and the Zagros Plateau in Iran. Inter- secting atmospheric

  8. Impact of external industrial sources on the regional and local SO[subscript 2] and O[subscript 3] levels of the Mexico megacity

    E-Print Network [OSTI]

    Almanza, Victor

    The air quality of megacities can be influenced by external emission sources on both global and regional scales. At the same time their outflow emissions can exert an impact to the surrounding environment. The present study ...

  9. AN ANALYTICAL MODEL OF THE LARGE NEUTRAL REGIONS DURING THE LATE STAGE OF REIONIZATION

    E-Print Network [OSTI]

    Xu, Yidong

    In this paper, we investigate the nature and distribution of large neutral regions during the late epoch of reionization. In the "bubble model" of reionization, the mass distribution of large ionized regions ("bubbles") ...

  10. On fast trust region methods for quadratic models with linear ...

    E-Print Network [OSTI]

    2014-08-28T23:59:59.000Z

    employs conjugate gradients with termination at the trust region boundary. In particular, we ... An extension to the conjugate gradient method for searching round.

  11. Reservoir quality, sediment source, and regional aspects of Norphlet Formation, South State Line field, Greene County, Mississippi

    SciTech Connect (OSTI)

    Thomson, A.; Stancliffe, R.J.; Shew, R.D.

    1987-05-01T23:59:59.000Z

    South State Line field, discovered in 1970, is centrally located in the productive Jurassic Norphlet trend of the eastern Gulf Coast. The Norphlet Formation at South State Line has produced gas and condensate from normally pressured eolian sandstones at depths of more than 17,900 ft (5455 m). The 600-ft- (183-m) thick Norphlet Formation is composed of 100% sandstone and consists of two reservoir types: a poorer quality upper sandstone having low permeability (0.6 md) and a good-quality lower sandstone with better permeability (15.5 md). The upper sandstone exhibits tighter compaction of framework grains and more cement than the lower sandstone. Significantly, the upper sandstone contains authigenic illite (which promotes pressure solution), whereas the lower sandstone contains authigenic chlorite (which inhibits cementation and possibly pressure solution). On a regional scale, illite is the principal diagenetic clay mineral in the western area of the Norphlet trend (Mississippi to Texas), whereas chlorite is the principal diagenetic clay mineral in the east (Alabama to Florida). Not surprisingly, reservoir quality is poorer in the western portion of the trend. A comparison of framework grains in the upper and lower sandstones shows no significant compositional differences. Both are mature arkosic sandstones with a transitional-continental source (eastern Appalachians). No evidence was seen of a quartz-rich Ouachita or cratonic source. Volcanic and plutonic rock fragments are slightly more abundant in the lower sandstone, possibly reflecting a shifting of compositional terranes within a single source area along the eastern side of the Appalachians. The lower Norphlet sandstone may have been derived from Triassic volcanics, whereas the upper sandstone may have been derived from a more metamorphic source.

  12. Solar Resource Assessment: Databases, Measurements, Models, and Information Sources (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2008-10-01T23:59:59.000Z

    Fact sheet for Solar Resource Assessment Workshop, Denver CO, Oct 29, 2008: ?Solar Resource Assessment Databases, Measurements, Models, and Information Sources

  13. PARAMETER ESTIMATION BASED MODELS OF WATER SOURCE HEAT PUMPS

    E-Print Network [OSTI]

    ......................................................................................................... 4 2.1. Heat Pump and Chiller Models

  14. A novel approach to modeling pH-sensitive regions within proteins 0 A novel approach to modeling pH-sensitive regions within proteins

    E-Print Network [OSTI]

    Gray, Jeffrey J.

    of a cell, is the next logical extension of genomics.5,6 Proteomic research has a myriad of applicationsA novel approach to modeling pH-sensitive regions within proteins 0 A novel approach to modeling p. A substantial literature review yielded no protein prediction algorithms capable of modeling p

  15. An Analytic Linear Accelerator Source Model for Monte Carlo Dose Calculations. I. Model Representation and Construction

    E-Print Network [OSTI]

    Tian, Zhen; Folkerts, Michael; Shi, Feng; Jiang, Steve B; Jia, Xun

    2015-01-01T23:59:59.000Z

    Monte Carlo (MC) simulation is considered as the most accurate method for radiation dose calculations. Accuracy of a source model for a linear accelerator is critical for the overall dose calculation accuracy. In this paper, we presented an analytical source model that we recently developed for GPU-based MC dose calculations. A key concept called phase-space-ring (PSR) was proposed. It contained a group of particles that are of the same type and close in energy and radial distance to the center of the phase-space plane. The model parameterized probability densities of particle location, direction and energy for each primary photon PSR, scattered photon PSR and electron PSR. For a primary photon PSRs, the particle direction is assumed to be from the beam spot. A finite spot size is modeled with a 2D Gaussian distribution. For a scattered photon PSR, multiple Gaussian components were used to model the particle direction. The direction distribution of an electron PSRs was also modeled as a 2D Gaussian distributi...

  16. HYBRID GROUND SOURCE HEAT PUMP SYSTEM SIMULATION USING VISUAL MODELING TOOL FOR HVACSIM+

    E-Print Network [OSTI]

    HYBRID GROUND SOURCE HEAT PUMP SYSTEM SIMULATION USING VISUAL MODELING TOOL FOR HVACSIM+ M.H. Khan, 74078, USA ABSTRACT This paper presents a simulation of a hybrid ground source heat pump system, performed using a new graphical user interface for HVACSIM+. Hybrid ground source heat pump systems

  17. Diagnostics and modeling of plasma processes in ion sources

    E-Print Network [OSTI]

    Vertes, Akos

    radiation (inductively coupled plasma (ICI'), microwave-induced plasma (MU'), pulsed laser). The present-8), radiofrequency (9) and microwave ion sources (10-12) are under intense investigation. Diligent research

  18. Physics and modeling of an end-Hall (gridless) ion source

    SciTech Connect (OSTI)

    Oudini, N. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); Hagelaar, G. J. M.; Boeuf, J.-P.; Garrrigues, L. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

    2011-04-01T23:59:59.000Z

    In an end-Hall source, an ion beam is extracted from a magnetized plasma and accelerated by the plasma electric field without grids. The principle of end-Hall sources is similar to that of Hall effect thrusters (or closed-drift thrusters), but their design is optimized for processing applications (ion beam assisted deposition or substrate cleaning) rather than propulsion. The beam divergence is larger in end-Hall ion sources, and these sources can operate at low ion energies. Although end-Hall sources are commonly used in the surface processing industry, no detailed modeling of these sources is available, and their operation is quite empirical. In this paper, a self-consistent, two-dimensional, quasineutral model of an end-Hall ion source is developed and used in order to improve the understanding of the basic physics of these plasma sources and to quantify the parameters controlling the properties of the extracted ion beam.

  19. An Analytic Linear Accelerator Source Model for Monte Carlo dose calculations. II. Model Utilization in a GPU-based Monte Carlo Package and Automatic Source Commissioning

    E-Print Network [OSTI]

    Tian, Zhen; Li, Yongbao; Shi, Feng; Jiang, Steve B; Jia, Xun

    2015-01-01T23:59:59.000Z

    We recently built an analytical source model for GPU-based MC dose engine. In this paper, we present a sampling strategy to efficiently utilize this source model in GPU-based dose calculation. Our source model was based on a concept of phase-space-ring (PSR). This ring structure makes it effective to account for beam rotational symmetry, but not suitable for dose calculations due to rectangular jaw settings. Hence, we first convert PSR source model to its phase-space let (PSL) representation. Then in dose calculation, different types of sub-sources were separately sampled. Source sampling and particle transport were iterated. So that the particles being sampled and transported simultaneously are of same type and close in energy to alleviate GPU thread divergence. We also present an automatic commissioning approach to adjust the model for a good representation of a clinical linear accelerator . Weighting factors were introduced to adjust relative weights of PSRs, determined by solving a quadratic minimization ...

  20. Regional dust model performance during SAMUM 2006 K. Haustein,1

    E-Print Network [OSTI]

    established forecast model delivering daily products for North Africa, Europe, Middle East and Asia http

  1. Evaluation of Reconstructed Images of Regional Lung Changes Using a Model

    E-Print Network [OSTI]

    Adler, Andy

    Evaluation of Reconstructed Images of Regional Lung Changes Using a Model Robert P, Patterson1 A and Patterson 2004, Yang and Patterson 2010). In order to answer questions about regional lung changes, two regions were created in the posterior portion of the right lung where the resistivity can be independently

  2. Theoretical modeling of propagation of magneto-acoustic waves in magnetic regions below sunspots

    E-Print Network [OSTI]

    E. Khomenko; A. Kosovichev; M. Collados; K. Parchevsky; V. Olshevsky

    2008-12-10T23:59:59.000Z

    We use 2D numerical simulations and eikonal approximation, to study properties of MHD waves traveling below the solar surface through the magnetic structure of sunspots. We consider a series of magnetostatic models of sunspots of different magnetic field strengths, from 10 Mm below the photosphere to the low chromosphere. The purpose of these studies is to quantify the effect of the magnetic field on local helioseismology measurements by modeling waves excited by sub-photospheric sources. Time-distance propagation diagrams and wave travel times are calculated for models of various field strength and compared to the non-magnetic case. The results clearly indicate that the observed time-distance helioseismology signals in sunspot regions correspond to fast MHD waves. The slow MHD waves form a distinctly different pattern in the time-distance diagram, which has not been detected in observations. The numerical results are in good agreement with the solution in the short-wavelength (eikonal) approximation, providing its validation. The frequency dependence of the travel times is in a good qualitative agreement with observations.

  3. Modeling branching effects on source-sink relationships of the cotton plant , Vronique Letort2

    E-Print Network [OSTI]

    Boyer, Edmond

    -structural models simulate the architectural development and physiological functioning of plants. Most of them to trace back the dynamics of the source-sink relationship within the plant [12]. A few studies have beenModeling branching effects on source-sink relationships of the cotton plant Dong Li1 , Véronique

  4. RISG-M-2482 COMPUTER MODELLING OF RADIOACTIVE SOURCE TERMS

    E-Print Network [OSTI]

    /INTOR workshops. INIS descriptors: M CODES; MATHEMATICAL MODELS; MONTE CARLO METHOD; NEUTRON TRANSPORT; TOKAMAK

  5. Spectrum and Morphology of the Two Brightest Milagro Sources in the Cygnus Region: MGRO J2019+37 and MGRO J2031+41

    E-Print Network [OSTI]

    Abdo, A A; Aune, T; Berley, D; Bonamente, E; Christopher, G E; DeYoung, T; Dingus, B L; Ellsworth, R W; Galbraith-Frew, J G; Gonzalez, M M; Goodman, J A; Hoffman, C M; Huentemeyer, P H; Kolterman, B E; Linnemann, J T; McEnery, J E; Mincer, A I; Morgan, T; Nemethy, P; Pretz, J; Ryan, J M; Parkinson, P M Saz; Sinnis, G; Smith, A J; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2012-01-01T23:59:59.000Z

    The Cygnus region is a very bright and complex portion of the TeV sky, host to unidentified sources and a diffuse excess with respect to conventional cosmic-ray propagation models. Two of the brightest TeV sources, MGRO J2019+37 and MGRO J2031+41, are analyzed using Milagro data with a new technique, and their emission is tested under two different spectral assumptions: a power law and a power law with an exponential cutoff. The new analysis technique is based on an energy estimator that uses the fraction of photomultiplier tubes in the observatory that detect the extensive air shower. The photon spectrum is measured in the range 1 to 200 TeV using the last 3 years of Milagro data (2005-2008), with the detector in its final configuration. MGRO J2019+37 is detected with a significance of 12.3 standard deviations ($\\sigma$), and is better fit by a power law with an exponential cutoff than by a simple power law, with a probability $>98$% (F-test). The best-fitting parameters for the power law with exponential cu...

  6. Wellbore Heat Transfer Model for Wax Deposition in Permafrost Region

    E-Print Network [OSTI]

    Cui, Xiaoting

    2012-05-31T23:59:59.000Z

    Producing waxy oil in arctic area may cause wax deposited on the well wall. Since wax deposition is strongly thermal related, accurate heat transfer model is necessary in predicting and preventing wax depostion. A mathematical model was derived...

  7. Development of Frameworks for Robust Regional Climate Modeling PRINCIPAL INVESTIGATOR: Moetasim Ashfaq

    E-Print Network [OSTI]

    goals of climate modeling. Water supports the ecosystems as well as a wide range of human activities to improve region- al predictions of the hydrologic cycle to address climate change impacts, adaptationDevelopment of Frameworks for Robust Regional Climate Modeling PRINCIPAL INVESTIGATOR: Moetasim

  8. SolarStat: Modeling Photovoltaic Sources through Stochastic Markov Processes

    E-Print Network [OSTI]

    Rossi, Michele

    of the society, from industrial manufacturing activities to smart cities, public buildings, etc. Being able of "smart cities" and the Internet of Things (IoT) [2], [3], these re- source constrained small sensing of the energy absorbed from the power grid (which is usually obtained from carbon fossil or nuclear power plants

  9. Optimal Filtering of Source Address Prefixes: Models and Algorithms

    E-Print Network [OSTI]

    Markopoulou, Athina

    , malicious code prop- agation, and distributed denial-of-service (DDoS) attacks? One mechanism for blocking this framework, we study four practical cases of source address/prefix filtering, which correspond to different, malicious code propagation, spam, and distributed denial-of-service (DDoS) attacks? These activities cause

  10. Energy deposition in the body from external sources to chemically trigger cellular responses in desired localized regions

    E-Print Network [OSTI]

    Ibsen, Stuart Duncan

    2011-01-01T23:59:59.000Z

    blast region was not centered at the smaller microbubble because only the effectthe blast region measures at 49 µm in diameter. The effectblast region and measures at 12 µm in diameter. Discussion The effect

  11. Space Mapping: Models, Sensitivities, and Trust-Regions Methods 1 ...

    E-Print Network [OSTI]

    We consider also a di erent perspective of space mapping and apply it, ... built by composition of the space mapping and the coarse model is a regular function.

  12. MODELLING GROUNDWATER FLOW ON THE REGIONAL SCALE IN THE UPPER DANUBE CATCHMENT (GERMANY)

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    MODELLING GROUNDWATER FLOW ON THE REGIONAL SCALE IN THE UPPER DANUBE CATCHMENT (GERMANY) Roland.barthel@iws.uni-stuttgart.de Abstract. A groundwater flow model for the Upper Danube catchment (A=77,000km2 at gauge Passau, Germany coupled models. Modelling of groundwater flow, using coupled deterministic and hydrological approaches

  13. Foramol carbonate shelves as depositional site and source area: Recent and ancient examples from the Mediterranean region

    SciTech Connect (OSTI)

    Carannante, G.; Simone, L.

    1988-08-01T23:59:59.000Z

    In recent environments, only limited carbonate depositional areas are dominated by coral reefs. Such platforms frequently develop rimmed margins and are characterized by chlorozoan facies with large contributions of nonskeletal grains. They are practically limited to warm tropical seas. In temperate seas as well as anomalous tropical zones, large areas of the middle-outer shelf are covered by skeletal debris with variable amounts of mollusks, foraminifers, coralline algae, bryozoans, etc (foramol facies). Apart from the skeletal fragments derived from the shallow inner shelf and the contribution from local endobiota and epibiota, the source of the bioclastic sediments may be found in limited and scattered areas supporting active carbonate-producing assemblages. Fossil counterparts of similar deposits are present in the Mediterranean region (e.g., Spain, Italy, Malta, Libya), locally showing good reservoir properties. Examples are described from the Miocene of the Southern Apennines (Italy) where a variety rich in encrusting coralline algae is present, as well as from the Upper Cretaceous of the Southern Apennines and northwest Sardinia (Italy) where scattered rudistid buildups are associated with bioclastic sediments rich in coralline algae and bryozoans.

  14. Convergence of trust-region methods based on probabilistic models

    E-Print Network [OSTI]

    2013-10-24T23:59:59.000Z

    the list of applications—including molecular geometry optimization, circuit design, ... A complex mechanism of sample set maintenance is ... shown that one can build such models, meeting a Taylor type accuracy with high probability,.

  15. Data-based Construction of Convex Region Surrogate (CRS) Models

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    University Arul Sundaramoorthy, Jose M. Pinto Praxair Inc., Business and Supply Chain Optimization R Model of an Industrial Process. Real process data drawn from a Praxair plant Set 1 0.900 0.062 0

  16. Merging Models and Biomonitoring Data to Characterize Sources andPathways of Human Exposure to Organophosphorous Pesticides in the SalinasValley of California

    SciTech Connect (OSTI)

    McKone, Thomas E.; Castorina, Rosemary; Kuwabara, Yu; Harnly,Martha E.; Eskenazi, Brenda; Bradman, Asa

    2006-06-01T23:59:59.000Z

    By drawing on human biomonitoring data and limited environmental samples together with outputs from the CalTOX multimedia, multipathway source-to-dose model, we characterize cumulative intake of organophosphorous (OP) pesticides in an agricultural region of California. We assemble regional OP pesticide use, environmental sampling, and biological tissue monitoring data for a large and geographically dispersed population cohort of 592 pregnant Latina women in California (the CHAMACOS cohort). We then use CalTOX with regional pesticide usage data to estimate the magnitude and uncertainty of exposure and intake from local sources. We combine model estimates of intake from local sources with food intake based on national residue data to estimate for the CHAMACOS cohort cumulative median OP intake, which corresponds to expected levels of urinary dialkylphosphate (DAP) metabolite excretion for this cohort. From these results we develop premises about relative contributions from different sources and pathways of exposure. We evaluate these premises by comparing the magnitude and variation of DAPs in the CHAMACOS cohort with the whole U.S. population using data from the National Health and Nutrition Evaluation Survey (NHANES). This comparison supports the premise that in both populations diet is the common and dominant exposure pathway. Both the model results and biomarker comparison supports the observation that the CHAMACOS population has a statistically significant higher intake of OP pesticides that appears as an almost constant additional dose among all participants. We attribute the magnitude and small variance of this intake to non-dietary exposure in residences from local sources.

  17. Convolutive Demixing with Sparse Discrete Prior Models for Markov Sources

    E-Print Network [OSTI]

    Balan, Radu V.

    Rosca1 Siemens Corporate Research, 755 College Road East, Princeton, NJ 08540 {radu.balan, justinian.rosca}@siemens, or transformed domain (e.g. frequency domain). The mixing model is either instantaneous, or anechoic. The ICA

  18. A Markov Random Field model of contamination source identification in porous media flow

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    A Markov Random Field model of contamination source identification in porous media flow Jingbo Wang A contamination source identification problem in constant porous media flow is addressed by solving the advection-dispersion equation (ADE) with a hierarchical Bayesian computation method backward through time. The contaminant

  19. Interhemispheric Teleconnections from Tropical Heat Sources in Intermediate and Simple Models

    E-Print Network [OSTI]

    the prescribed tropical heating in both intensity and geographical extent and by inducing remote precipitation anomalies by interaction with the basic state. 1. Introduction Tropical heat sources can remotely influenceInterhemispheric Teleconnections from Tropical Heat Sources in Intermediate and Simple Models XUAN

  20. Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model: An

    E-Print Network [OSTI]

    Zhao, Xuepu

    Discrepancies in the Prediction of Solar Wind using Potential Field Source Surface Model. This inverse relation has been made use of in the prediction of solar wind speed at 1 AU using a potential between the magnetic flux tube expansion factor (FTE) at the source surface and the solar wind speed

  1. Regional Radiological Security Partnership in Southeast Asia – Increasing the Sustainability of Security Systems at the Site-Level by Using a Model Facility Approach

    SciTech Connect (OSTI)

    Chamberlain, Travis L.; Dickerson, Sarah; Ravenhill, Scott D.; Murray, Allan; Morris, Frederic A.; Herdes, Gregory A.

    2009-10-07T23:59:59.000Z

    In 2004, Australia, through the Australian Nuclear Science and Technology Organisation (ANSTO), created the Regional Security of Radioactive Sources (RSRS) project and partnered with the U.S. Department of Energy’s Global Threat Reduction Initiative (GTRI) and the International Atomic Energy Agency (IAEA) to form the Southeast Asian Regional Radiological Security Partnership (RRSP). The intent of the RRSP is to cooperate with countries in Southeast Asia to improve the security of their radioactive sources. This Southeast Asian Partnership supports objectives to improve the security of high risk radioactive sources by raising awareness of the need and developing national programs to protect and control such materials, improve the security of such materials, and recover and condition the materials no longer in use. The RRSP has utilized many tools to meet those objectives including: provision of physical protection upgrades, awareness training, physical protection training, regulatory development, locating and recovering orphan sources, and most recently - development of model security procedures at a model facility. This paper discusses the benefits of establishing a model facility, the methods employed by the RRSP, and three of the expected outcomes of the Model Facility approach. The first expected outcome is to increase compliance with source security guidance materials and national regulations by adding context to those materials, and illustrating their impact on a facility. Second, the effectiveness of each of the tools above is increased by making them part of an integrated system. Third, the methods used to develop the model procedures establishes a sustainable process that can ultimately be transferred to all facilities beyond the model. Overall, the RRSP has utilized the Model Facility approach as an important tool to increase the security of radioactive sources, and to position facilities and countries for the long term secure management of those sources.

  2. Gravitation law and source model in the anisotropic geometrodynamics

    E-Print Network [OSTI]

    Sergey Siparov

    2010-01-10T23:59:59.000Z

    The GRT modification taking into account the dependence of metric on the velocities of the sources is built. It is shown that this dependence follows from the equivalence principle and from the inseparability of the field equations and geodesics equations. As it is known, the latter are the conditions of the field equations solvability, and their form coincides with Newtonian one only in the lowest approximation. The obtained modification provides the explanation for the flat character of the rotation curves of spiral galaxies, for Tully-Fisher law, for some specific features of globular clusters behavior and for the essential excess of the observable gravitational lens effect over the predicted one. Neither dark matter nor arbitrary change of dynamics equations appeared to be needed. Important cosmological consequences are obtained.

  3. Modeling Functional Data Sources as Relations Simone Santini and Amarnath Gupta

    E-Print Network [OSTI]

    Gupta, Amarnath

    Modeling Functional Data Sources as Relations Simone Santini and Amarnath Gupta University, LNCS 3288, pp. 55­68, 2004. c Springer-Verlag Berlin Heidelberg 2004 #12;56 Simone Santini and Amarnath

  4. A validation of heat and carbon fluxes from highresolution land surface and regional models

    E-Print Network [OSTI]

    D'Andrea, Fabio

    ) or regional climate models (RCMs) [Alessandri et al., 2007; Steiner et al., 2009]. [3., 2006; Alessandri et al., 2007; Jarlan et al., 2008; Steiner et al., 2009]. However, the SVAT models models do not account for the role of terrestrial vegetation in the carbon cycle variability [Alessandri

  5. Characterization of the ITER model negative ion source during long pulse operation

    SciTech Connect (OSTI)

    Hemsworth, R.S.; Boilson, D.; Crowley, B.; Homfray, D.; Esch, H.P.L. de; Krylov, A.; Svensson, L. [Association EURATOM-CEA, CEA Cadarache, F-13108, St. Paul lez Durance (France); Association EURATOM-DCU, PRL/NCPST, Glasnevin, Dublin 13 (Ireland); Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Association EURATOM-CEA, CEA Cadarache, F-13108, St. Paul lez Durance (France)

    2006-03-15T23:59:59.000Z

    It is foreseen to operate the neutral beam system of the International Thermonuclear Experimental Reactor (ITER) for pulse lengths extending up to 1 h. The performance of the KAMABOKO III negative ion source, which is a model of the source designed for ITER, is being studied on the MANTIS test bed at Cadarache. This article reports the latest results from the characterization of the ion source, in particular electron energy distribution measurements and the comparison between positive ion and negative ion extraction from the source.

  6. DYNAMIC MODELLING OF AUTONOMOUS POWER SYSTEMS INCLUDING RENEWABLE POWER SOURCES.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (thermal, gas, diesel) and renewable (hydro, wind) power units. The objective is to assess the impact - that have a special dynamic behaviour, and the wind turbines. Detailed models for each one of the power system components are developed. Emphasis is given in the representation of different hydro power plant

  7. Carbonaceous aerosols recorded in a southeastern Tibetan glacier: analysis of temporal variations and model estimates of sources and radiative forcing

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; et al

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956–2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of BC and OC with higher respective concentrations but a lower OC / BC ratio in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source–receptor relationships between four Asian source regions and the southeastern Tibetan Plateau as a receptor. The model results show that South Asia hasmore »the largest contribution to the present-day (1996–2005) mean BC deposition at the ice-core drilling site during the non-monsoon season (October to May) (81%) and all year round (74%), followed by East Asia (14% to the non-monsoon mean and 21% to the annual mean). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from the late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia (as the primary contributor to annual mean BC deposition). Moreover, the increasing trend of the OC / BC ratio since the early 1990s indicates a growing contribution of coal combustion and/or biomass burning to the emissions. The estimated radiative forcing induced by BC and OC impurities in snow has increased since 1980, suggesting an increasing potential influence of carbonaceous aerosols on the Tibetan glacier melting and the availability of water resources in the surrounding regions. Our study indicates that more attention to OC is merited because of its non-negligible light absorption and the recent rapid increases evident in the ice-core record.« less

  8. Carbonaceous Aerosols Recorded in a Southeastern Tibetan Glacier: Analysis of Temporal Variations and Model Estimates of Sources and Radiative Forcing

    SciTech Connect (OSTI)

    Wang, Mo; Xu, B.; Cao, J.; Tie, X.; Wang, Hailong; Zhang, Rudong; Qian, Yun; Rasch, Philip J.; Zhao, Shuyu; Wu, Guangjian; Zhao, Huabiao; Joswiak, Daniel R.; Li, Jiule; Xie, Ying

    2015-01-01T23:59:59.000Z

    High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956-2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of OC/BC ratio with higher values in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source-receptor relationships between four Asian source regions and the southern Tibetan Plateau as a receptor. The model results show that South Asia is a primary contributor during the non-monsoon season (October to May) (81%) and on an annual basis (74%), followed by East Asia (14% and 21%, respectively). The ice-core record also indicates stable and relatively low BC and OC deposition fluxes from late 1950s to 1980, followed by an overall increase to recent years. This trend is consistent with the BC and OC emission inventories and the fuel consumption of South Asia as the primary contributor. Moreover, the increasing trend of OC/BC ratio since the early 1990s indicates a growing contribution of coal combustion and biomass burning to the emissions. The estimated radiative forcing induced by BC/OC impurities in snow has increased since 1980, suggesting an increasing influence of carbonaceous aerosols on the Tibetan glacier melting, influencing the availability of water resources in the surrounding regions. Our study indicates that the role of OC deserves more attention because of its non-negligible light absorption and the more rapid increase than BC

  9. Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West Africa

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    1 Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West.J.S. SONNEVELD [1] Institute of Hydraulic Engineering, Universitaet Stuttgart, Germany (Roland Conservation University of Bonn, Germany [3] Institute of Landscape Planning and Ecology, University

  10. PROCESS MODELING AND ANALYSIS FOR RECOVERY OF PUBE SOURCES AT LOS ALAMOS

    SciTech Connect (OSTI)

    D. KORNREICH; ET AL

    2000-11-01T23:59:59.000Z

    Los Alamos National Laboratory maintains one of the premier plutonium processing facilities in the country. The plutonium facility supports several defense- and nondefense-related missions. This paper describes process-modeling efforts focused on the operations related to the Radioactive Source Recovery Program, which recovers the plutonium from plutonium-beryllium neutron sources. This program accomplishes at least two goals: it is evidence of good stewardship of a national resource, plutonium, and destroys a potential health hazard, the neutron source, by separating the plutonium from the beryllium in sources that are no longer being used in various industries or the military. We examine the processes related to source recovery operations in terms of throughput, ionizing radiation exposure to workers, and mass balances using two discrete-event simulation tools: Extend{trademark}, which is commercially available; and ProMoS, which is in-house software specifically tailored for modeling nuclear-materials operations.

  11. Travel-time distribution from a finite line contamination source to an extraction well with regional flow

    E-Print Network [OSTI]

    Zhan, Hongbin

    to an extraction well with regional flow Hongbin Zhan a,*, Dongmin Sun b a Department of Geology and Geophyscis

  12. MODELING MAGNETIC FIELD STRUCTURE OF A SOLAR ACTIVE REGION CORONA USING NONLINEAR FORCE-FREE FIELDS IN SPHERICAL GEOMETRY

    SciTech Connect (OSTI)

    Guo, Y.; Ding, M. D. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Liu, Y.; Sun, X. D. [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States); DeRosa, M. L. [Lockheed Martin Advanced Technology Center, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Wiegelmann, T., E-mail: guoyang@nju.edu.cn [Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Strasse 2, D-37191 Katlenburg-Lindau (Germany)

    2012-11-20T23:59:59.000Z

    We test a nonlinear force-free field (NLFFF) optimization code in spherical geometry using an analytical solution from Low and Lou. Several tests are run, ranging from idealized cases where exact vector field data are provided on all boundaries, to cases where noisy vector data are provided on only the lower boundary (approximating the solar problem). Analytical tests also show that the NLFFF code in the spherical geometry performs better than that in the Cartesian one when the field of view of the bottom boundary is large, say, 20 Degree-Sign Multiplication-Sign 20 Degree-Sign . Additionally, we apply the NLFFF model to an active region observed by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory (SDO) both before and after an M8.7 flare. For each observation time, we initialize the models using potential field source surface (PFSS) extrapolations based on either a synoptic chart or a flux-dispersal model, and compare the resulting NLFFF models. The results show that NLFFF extrapolations using the flux-dispersal model as the boundary condition have slightly lower, therefore better, force-free, and divergence-free metrics, and contain larger free magnetic energy. By comparing the extrapolated magnetic field lines with the extreme ultraviolet (EUV) observations by the Atmospheric Imaging Assembly on board SDO, we find that the NLFFF performs better than the PFSS not only for the core field of the flare productive region, but also for large EUV loops higher than 50 Mm.

  13. Towards a consistent model for Neutron-Star Sources

    E-Print Network [OSTI]

    W. Kundt

    2002-08-30T23:59:59.000Z

    We are still far from understanding how pulsars pulse, how neutron stars are born, what neutron stars can emit, and in which way they do this. In this short communication, I list 18 alternatives -- several of them old, a few of them new -- which are handled differently by different authors but all of which are crucial for a model of neutron stars to be viable.

  14. Quantification of explosion source characteristics from near-source, regional and teleseismic distances. Final report, 23 February 1987-31 July 1989

    SciTech Connect (OSTI)

    Stump, B.; Reamer, S.; Anderson, D.; Olsen, K.; Reinke, R.

    1989-07-31T23:59:59.000Z

    Work over the contract period is summarized in four papers: (1) Source Parameter Estimation for Large, Bermed, Surface Chemical Explosions; (2) Seismic Wave Generation by Mine Blasts; (3) Pomona Quarry Seismic Experiment, Near-Source Data; and (4) MISTY ECHO, The Seismic Source Physics Experiment. The first paper attempts to qualify source differences between large surface chemical explosions ranging in yields from 0.075 to 1.65 kilotons. The second paper documents millisecond delay blasting practices in the mining industry and illustrates the effects of these practices on near-source seismic observations. The effects of scatter in design blasting times is illustrated. A set of experiments designed to begin the comparison between single and production mining explosions are described in the third paper. The multiple explosion production shot was documented with high speed photography so that the design and actual firing times of the individual explosions could be compared. The final paper is a preliminary data report describing the first of a series of free field and free surface seismic experiments designed to document the effects of the free surface on seismic radiation from underground nuclear explosions. The particular experiment, MISTY ECHO, was detonated in Rainier Mesa at the Nevada Test Site.

  15. Resource Planning Model: An Integrated Resource Planning and Dispatch Tool for Regional Electric Systems

    SciTech Connect (OSTI)

    Mai, T.; Drury, E.; Eurek, K.; Bodington, N.; Lopez, A.; Perry, A.

    2013-01-01T23:59:59.000Z

    This report introduces a new capacity expansion model, the Resource Planning Model (RPM), with high spatial and temporal resolution that can be used for mid- and long-term scenario planning of regional power systems. Although RPM can be adapted to any geographic region, the report describes an initial version of the model adapted for the power system in Colorado. It presents examples of scenario results from the first version of the model, including an example of a 30%-by-2020 renewable electricity penetration scenario.

  16. The Analytical Repository Source-Term (AREST) model: Description and documentation

    SciTech Connect (OSTI)

    Liebetrau, A.M.; Apted, M.J.; Engel, D.W.; Altenhofen, M.K.; Strachan, D.M.; Reid, C.R.; Windisch, C.F.; Erikson, R.L.; Johnson, K.I.

    1987-10-01T23:59:59.000Z

    The geologic repository system consists of several components, one of which is the engineered barrier system. The engineered barrier system interfaces with natural barriers that constitute the setting of the repository. A model that simulates the releases from the engineered barrier system into the natural barriers of the geosphere, called a source-term model, is an important component of any model for assessing the overall performance of the geologic repository system. The Analytical Repository Source-Term (AREST) model being developed is one such model. This report describes the current state of development of the AREST model and the code in which the model is implemented. The AREST model consists of three component models and five process models that describe the post-emplacement environment of a waste package. All of these components are combined within a probabilistic framework. The component models are a waste package containment (WPC) model that simulates the corrosion and degradation processes which eventually result in waste package containment failure; a waste package release (WPR) model that calculates the rates of radionuclide release from the failed waste package; and an engineered system release (ESR) model that controls the flow of information among all AREST components and process models and combines release output from the WPR model with failure times from the WPC model to produce estimates of total release. 167 refs., 40 figs., 12 tabs.

  17. Hadron Production Model Developments and Benchmarking in the 0.7 - 12 GeV Energy Region

    E-Print Network [OSTI]

    N. V. Mokhov; K. K. Gudima; S. I. Striganov

    2014-08-29T23:59:59.000Z

    Driven by the needs of the intensity frontier projects with their Megawatt beams, e.g., ESS, FAIR and Project X, and their experiments, the event generators of the MARS15 code have been recently improved. After thorough analysis and benchmarking against data, including the newest ones by the HARP collaboration, both the exclusive and inclusive particle production models were further developed in the crucial for the above projects - but difficult from a theoretical standpoint - projectile energy region of 0.7 to 12 GeV. At these energies, modelling of prompt particle production in nucleon-nucleon and pion-nucleon inelastic reactions is now based on a combination of phase-space and isobar models. Other reactions are still modeled in the framework of the Quark-Gluon String Model. Pion, kaon and strange particle production and propagation in nuclear media are improved. For the alternative inclusive mode, experimental data on large-angle (> 20 degrees) pion production in hadron-nucleus interactions are parameterized in a broad energy range using a two-source model. It is mixed-and-matched with the native MARS model that successfully describes low-angle pion production data. Predictions of both new models are - in most cases - in a good agreement with experimental data obtained at CERN, JINR, LANL, BNL and KEK.

  18. 11.482J / 1.285J / ESD.193J Regional Socioeconomic Impact Analysis and Modeling, Fall 2005

    E-Print Network [OSTI]

    Polenske, Karen R.

    Reviews regional economic theories and models and provides students with experience in using alternative economic impact assessment models on microcomputers. Problem sets are oriented around infrastructure, housing, energy, ...

  19. 11.482J / 1.285J / ESD.193J Regional Socioeconomic Impact Analysis and Modeling, Fall 2004

    E-Print Network [OSTI]

    Polenske, Karen R.

    Reviews regional economic theories and models and provides students with experience in using alternative economic impact assessment models on microcomputers. Problem sets are oriented around infrastructure, housing, energy, ...

  20. SOURCE SEPARATION USING SPARSE DISCRETE PRIOR MODELS Radu Balan, Justinian Rosca

    E-Print Network [OSTI]

    Balan, Radu V.

    SOURCE SEPARATION USING SPARSE DISCRETE PRIOR MODELS Radu Balan, Justinian Rosca Siemens Corporate Research 755 College Road East Princeton, NJ 08540 e-mail: radu.balan,justinian.rosca¡ @siemens, in their origi- nal domain, or transformed domain (e.g. frequency domain). The mixing model is either

  1. Development of source functions for modeling dissolution of residual DNAPL fingers in the saturated zone 

    E-Print Network [OSTI]

    Johnson, Brian Scott

    1993-01-01T23:59:59.000Z

    fmger in the saturated zone. Modeling dissolution from a residual fmger can be approached in one of two ways: as an equilibrium process or as a rate dependent kinetic process. Development of a source term for modeling the dissolution from remediation...

  2. Air dispersion modeling of particulate matter from ground-level area sources

    E-Print Network [OSTI]

    Meister, Michael Todd

    2000-01-01T23:59:59.000Z

    obtained from a dispersion model. The model currently approved by EPA, the Industrial Source Complex, Version 3 - Short Term (ISC3-ST), over-predicts downwind concentrations of PM by as much two orders of magnitude. As a result, a facility may be denied a...

  3. Performance Evaluation of a ground source heat pump system based on ANN and ANFIS models

    E-Print Network [OSTI]

    Sun, W.; Hu, P.; Lei, F.; Zhu, N.; Zhang,J.

    2014-01-01T23:59:59.000Z

    Performance evaluation of a ground source heat pump system based on ANN and ANFIS models Weijuan SUN a, Pingfang HUa,*, Fei Leia, Na Zhua, Jiangning Zhanga aHuazhong University of Science and Technology, Wuhan 430074, P. R. China Abstract...: The aim of this work is to calculate the heat pump coefficient of performance (COP) and the system COP of a ground source heat pump (GSHP) system based on an artificial neural network (ANN) model and (adaptive neuro-fuzzy inference system (ANFIS) model...

  4. Coupling of Integrated Biosphere Simulator to Regional Climate Model version 3

    E-Print Network [OSTI]

    Winter, Jonathan (Jonathan Mark)

    2006-01-01T23:59:59.000Z

    Presented in this thesis is a description of the coupling of Integrated Biosphere Simulator (IBIS) to Regional Climate Model version 3 (RegCM3), and an assessment of the coupled model (RegCM3-IBIS). RegCM3 is a 3-dimensional, ...

  5. An improved model of the lightning electromagnetic field interaction with the D-region ionosphere

    E-Print Network [OSTI]

    14 March 2012. [1] We present an improved time-domain model of the lightning electromagnetic pulse. Introduction [2] Lightning discharges produce both an electromagnetic pulse (EMP), due to the rapid lightningAn improved model of the lightning electromagnetic field interaction with the D-region ionosphere R

  6. SPECTRUM AND MORPHOLOGY OF THE TWO BRIGHTEST MILAGRO SOURCES IN THE CYGNUS REGION: MGRO J2019+37 AND MGRO J2031+41

    SciTech Connect (OSTI)

    Abdo, A. A.; Abeysekara, U.; Linnemann, J. T. [Department of Physics and Astronomy, Michigan State University, 3245 BioMedical Physical Sciences Building, East Lansing, MI 48824 (United States); Allen, B. T. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Aune, T. [Santa Cruz Institute for Particle Physics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Berley, D.; Goodman, J. A. [Department of Physics, University of Maryland, College Park, MD 20742 (United States); Bonamente, E.; Galbraith-Frew, J. G.; Huentemeyer, P. H.; Hui, C. M. [Department of Physics, Michigan Technological University, Houghton, MI 49931 (United States); Christopher, G. E.; Kolterman, B. E.; Mincer, A. I. [Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); DeYoung, T. [Department of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Dingus, B. L.; Hoffman, C. M. [Group P-23, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Ellsworth, R. W. [Department of Physics and Astronomy, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Gonzalez, M. M. [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, 74D.F., Mexico 04510 (Mexico); McEnery, J. E., E-mail: ebonamen@mtu.edu, E-mail: petra@mtu.edu [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); and others

    2012-07-10T23:59:59.000Z

    The Cygnus region is a very bright and complex portion of the TeV sky, host to unidentified sources and a diffuse excess with respect to conventional cosmic-ray propagation models. Two of the brightest TeV sources, MGRO J2019+37 and MGRO J2031+41, are analyzed using Milagro data with a new technique, and their emission is tested under two different spectral assumptions: a power law and a power law with an exponential cutoff. The new analysis technique is based on an energy estimator that uses the fraction of photomultiplier tubes in the observatory that detect the extensive air shower. The photon spectrum is measured in the range 1-100 TeV using the last three years of Milagro data (2005-2008), with the detector in its final configuration. An F-test indicates that MGRO J2019+37 is better fit by a power law with an exponential cutoff than by a simple power law. The best-fitting parameters for the power law with exponential cutoff model are a normalization at 10 TeV of 7{sup +5}{sub -2} Multiplication-Sign 10{sup -10} s{sup -1} m{sup -2} TeV{sup -1}, a spectral index of 2.0{sup +0.5}{sub -1.0}, and a cutoff energy of 29{sup +50}{sub -16} TeV. MGRO J2031+41 shows no evidence of a cutoff. The best-fitting parameters for a power law are a normalization of 2.1{sup +0.6}{sub -0.6} Multiplication-Sign 10{sup -10} s{sup -1} m{sup -2} TeV{sup -1} and a spectral index of 3.22{sup +0.23}{sub -0.18}. The overall flux is subject to a {approx}30% systematic uncertainty. The systematic uncertainty on the power-law indices is {approx}0.1. Both uncertainties have been verified with cosmic-ray data. A comparison with previous results from TeV J2032+4130, MGRO J2031+41, and MGRO J2019+37 is also presented.

  7. Regional groundwater flow and tritium transport modeling and risk assessment of the underground test area, Nevada Test Site, Nevada

    SciTech Connect (OSTI)

    None

    1997-10-01T23:59:59.000Z

    The groundwater flow system of the Nevada Test Site and surrounding region was evaluated to estimate the highest potential current and near-term risk to the public and the environment from groundwater contamination downgradient of the underground nuclear testing areas. The highest, or greatest, potential risk is estimated by assuming that several unusually rapid transport pathways as well as public and environmental exposures all occur simultaneously. These conservative assumptions may cause risks to be significantly overestimated. However, such a deliberate, conservative approach ensures that public health and environmental risks are not underestimated and allows prioritization of future work to minimize potential risks. Historical underground nuclear testing activities, particularly detonations near or below the water table, have contaminated groundwater near testing locations with radioactive and nonradioactive constituents. Tritium was selected as the contaminant of primary concern for this phase of the project because it is abundant, highly mobile, and represents the most significant contributor to the potential radiation dose to humans for the short term. It was also assumed that the predicted risk to human health and the environment from tritium exposure would reasonably represent the risk from other, less mobile radionuclides within the same time frame. Other contaminants will be investigated at a later date. Existing and newly collected hydrogeologic data were compiled for a large area of southern Nevada and California, encompassing the Nevada Test Site regional groundwater flow system. These data were used to develop numerical groundwater flow and tritium transport models for use in the prediction of tritium concentrations at hypothetical human and ecological receptor locations for a 200-year time frame. A numerical, steady-state regional groundwater flow model was developed to serve as the basis for the prediction of the movement of tritium from the underground testing areas on a regional scale. The groundwater flow model was used in conjunction with a particle-tracking code to define the pathlines followed by groundwater particles originating from 415 points associated with 253 nuclear test locations. Three of the most rapid pathlines were selected for transport simulations. These pathlines are associated with three nuclear test locations, each representing one of the three largest testing areas. These testing locations are: BOURBON on Yucca Flat, HOUSTON on Central Pahute Mesa, and TYBO on Western Pahute Mesa. One-dimensional stochastic tritium transport simulations were performed for the three pathlines using the Monte Carlo method with Latin hypercube sampling. For the BOURBON and TYBO pathlines, sources of tritium from other tests located along the same pathline were included in the simulations. Sensitivity analyses were also performed on the transport model to evaluate the uncertainties associated with the geologic model, the rates of groundwater flow, the tritium source, and the transport parameters. Tritium concentration predictions were found to be mostly sensitive to the regional geology in controlling the horizontal and vertical position of transport pathways. The simulated concentrations are also sensitive to matrix diffusion, an important mechanism governing the migration of tritium in fractured carbonate and volcanic rocks. Source term concentration uncertainty is most important near the test locations and decreases in importance as the travel distance increases. The uncertainty on groundwater flow rates is as important as that on matrix diffusion at downgradient locations. The risk assessment was performed to provide conservative and bounding estimates of the potential risks to human health and the environment from tritium in groundwater. Risk models were designed by coupling scenario-specific tritium intake with tritium dose models and cancer and genetic risk estimates using the Monte Carlo method. Estimated radiation doses received by individuals from chronic exposure to tritium, and the corre

  8. In situ measurements of speciated atmospheric mercury and the identification of source regions in the Mexico City Metropolitan Area

    E-Print Network [OSTI]

    Rutter, A. P.

    In order to expand the currently limited understanding of atmospheric mercury source-receptor relationships in the Mexico City Metropolitan Area, real time measurements of atmospheric mercury were made at a downtown urban ...

  9. Alternative water sources: Desalination model provides life-cycle costs of facility

    E-Print Network [OSTI]

    Supercinski, Danielle

    2009-01-01T23:59:59.000Z

    Story by Danielle Supercinski tx H2O | pg. 8 Alternative water sourcees Desalination model provides life-cycle costs of facility platform and design standards as DESAL ECONOMICS?, but created to analyze con- ventional surface water treatment... to determine the economic and financial life-cycle costs of building and operating four water treatment facilities in South Texas. One facility was the Southmost Regional Water Authority Regional Desalination Plant near Brownsville. Sturdi- vant said...

  10. Alternative water sources: Desalination model provides life-cycle costs of facility 

    E-Print Network [OSTI]

    Supercinski, Danielle

    2009-01-01T23:59:59.000Z

    Story by Danielle Supercinski tx H2O | pg. 8 Alternative water sourcees Desalination model provides life-cycle costs of facility platform and design standards as DESAL ECONOMICS?, but created to analyze con- ventional surface water treatment... to determine the economic and financial life-cycle costs of building and operating four water treatment facilities in South Texas. One facility was the Southmost Regional Water Authority Regional Desalination Plant near Brownsville. Sturdi- vant said...

  11. The Lifecycle of Bayesian Network Models Developed for Multi-Source Signature Assessment of Nuclear Programs

    SciTech Connect (OSTI)

    Gastelum, Zoe N.; White, Amanda M.; Whitney, Paul D.; Gosink, Luke J.; Sego, Landon H.

    2013-06-04T23:59:59.000Z

    The Multi-Source Signatures for Nuclear Programs project, part of Pacific Northwest National Laboratory’s (PNNL) Signature Discovery Initiative, seeks to computationally capture expert assessment of multi-type information such as text, sensor output, imagery, or audio/video files, to assess nuclear activities through a series of Bayesian network (BN) models. These models incorporate knowledge from a diverse range of information sources in order to help assess a country’s nuclear activities. The models span engineering topic areas, state-level indicators, and facility-specific characteristics. To illustrate the development, calibration, and use of BN models for multi-source assessment, we present a model that predicts a country’s likelihood to participate in the international nuclear nonproliferation regime. We validate this model by examining the extent to which the model assists non-experts arrive at conclusions similar to those provided by nuclear proliferation experts. We also describe the PNNL-developed software used throughout the lifecycle of the Bayesian network model development.

  12. Advanced methods for uncertainty quantification in tail regions of climate model predictions.

    SciTech Connect (OSTI)

    Safta, Cosmin; Debusschere, Bert J.; Najm, Habib N.; Sargsyan, Khachik

    2010-09-01T23:59:59.000Z

    Conventional methods for uncertainty quantification are generally challenged in the 'tails' of probability distributions. This is specifically an issue for many climate observables since extensive sampling to obtain a reasonable accuracy in tail regions is especially costly in climate models. Moreover, the accuracy of spectral representations of uncertainty is weighted in favor of more probable ranges of the underlying basis variable, which, in conventional bases does not particularly target tail regions. Therefore, what is ideally desired is a methodology that requires only a limited number of full computational model evaluations while remaining accurate enough in the tail region. To develop such a methodology, we explore the use of surrogate models based on non-intrusive Polynomial Chaos expansions and Galerkin projection. We consider non-conventional and custom basis functions, orthogonal with respect to probability distributions that exhibit fat-tailed regions. We illustrate how the use of non-conventional basis functions, and surrogate model analysis, improves the accuracy of the spectral expansions in the tail regions. Finally, we also demonstrate these methodologies using precipitation data from CCSM simulations.

  13. Source- and Age-Resolved Mechanistic Air Quality Models: Model Development and Application in Southeast Texas

    E-Print Network [OSTI]

    Zhang, Hongliang

    2012-07-16T23:59:59.000Z

    SOA account for 30-58% of the total SOA, indicating that long range transport is important. PAHs from anthropogenic sources can produce 4% of total anthropogenic SOA. Wild fire, vehicles, solvent and industries are the major sources. EC and OC...

  14. Transforming the representation of the boundary layer and low clouds for high-resolution regional climate modeling: Final report

    SciTech Connect (OSTI)

    Huang, Hsin-Yuan; Hall, Alex

    2013-07-24T23:59:59.000Z

    Stratocumulus and shallow cumulus clouds in subtropical oceanic regions (e.g., Southeast Pacific) cover thousands of square kilometers and play a key role in regulating global climate (e.g., Klein and Hartmann, 1993). Numerical modeling is an essential tool to study these clouds in regional and global systems, but the current generation of climate and weather models has difficulties in representing them in a realistic way (e.g., Siebesma et al., 2004; Stevens et al., 2007; Teixeira et al., 2011). While numerical models resolve the large-scale flow, subgrid-scale parameterizations are needed to estimate small-scale properties (e.g. boundary layer turbulence and convection, clouds, radiation), which have significant influence on the resolved scale due to the complex nonlinear nature of the atmosphere. To represent the contribution of these fine-scale processes to the resolved scale, climate models use various parameterizations, which are the main pieces in the model that contribute to the low clouds dynamics and therefore are the major sources of errors or approximations in their representation. In this project, we aim to 1) improve our understanding of the physical processes in thermal circulation and cloud formation, 2) examine the performance and sensitivity of various parameterizations in the regional weather model (Weather Research and Forecasting model; WRF), and 3) develop, implement, and evaluate the advanced boundary layer parameterization in the regional model to better represent stratocumulus, shallow cumulus, and their transition. Thus, this project includes three major corresponding studies. We find that the mean diurnal cycle is sensitive to model domain in ways that reveal the existence of different contributions originating from the Southeast Pacific land-masses. The experiments suggest that diurnal variations in circulations and thermal structures over this region are influenced by convection over the Peruvian sector of the Andes cordillera, while the mostly dry mountain-breeze circulations force an additional component that results in semi-diurnal variations near the coast. A series of numerical tests, however, reveal sensitivity of the simulations to the choice of vertical grid, limiting the possibility of solid quantitative statements on the amplitudes and phases of the diurnal and semidiurnal components across the domain. According to our experiments, the Mellor-Yamada-Nakanishi-Niino (MYNN) boundary layer scheme and the WSM6 microphysics scheme is the combination of schemes that performs best. For that combination, mean cloud cover, liquid water path, and cloud depth are fairly wellsimulated, while mean cloud top height remains too low in comparison to observations. Both microphysics and boundary layer schemes contribute to the spread in liquid water path and cloud depth, although the microphysics contribution is slightly more prominent. Boundary layer schemes are the primary contributors to cloud top height, degree of adiabaticity, and cloud cover. Cloud top height is closely related to surface fluxes and boundary layer structure. Thus, our study infers that an appropriate tuning of cloud top height would likely improve the low-cloud representation in the model. Finally, we show that entrainment governs the degree of adiabaticity, while boundary layer decoupling is a control on cloud cover. In the intercomparison study using WRF single-column model experiments, most parameterizations show a poor agreement of the vertical boundary layer structure when compared with large-eddy simulation models. We also implement a new Total-Energy/Mass- Flux boundary layer scheme into the WRF model and evaluate its ability to simulate both stratocumulus and shallow cumulus clouds. Result comparisons against large-eddy simulation show that this advanced parameterization based on the new Eddy-Diffusivity/Mass-Flux approach provides a better performance than other boundary layer parameterizations.

  15. Intrashelf basins: A geologic model for source-bed and reservoir facies deposition within carbonate shelves

    SciTech Connect (OSTI)

    Grover, G. Jr. (Sauid Aramco, Dhahran (Saudi Arabia))

    1993-09-01T23:59:59.000Z

    Intrashelf basins (moats, inshore basins, shelf basins, differentiated shelf, and deep-water lagoons of others) are depressions of varying sizes and shapes that occur within tectonically passive and regionally extensive carbonate shelves. Intrashelf basins grade laterally and downdip (seaward) into shallow-water carbonates of the regional shelf, are separated from the open marine basin by the shelf margin, and are largely filled by fine-grained subtidal sediments having attributes of shallow- and deeper water sedimentation. These basins are commonly fringed or overlain by carbonate sands, reefs, or buildups. These facies may mimic those that occur along the regional shelf margin, and they can have trends that are at a high angle to that of the regional shelf. Intrashelf basins are not intracratonic basins. The history of most intrashelf basins is a few million to a few tens of million of years. Examples of intrashelf basins are known throughout the Phanerozoic; the southern portion of the Holocene Belize shelf is a modern example of an intrashelf basin. Two types of intrashelf basins are recognized. Coastal basins pass updip into coastal clastics of the craton with the basin primarily filled by fine clastics. Shelf basins occur on the outer part of the shelf, are surrounded by shallow-water carbonate facies, and are filled by peloidal lime mud, pelagics, and argillaceous carbonates. Intrashelf basins are commonly the site of organic-rich, source-bed deposition, resulting in the close proximity of source beds and reservoir facies that may fringe or overlie the basin. Examples of hydrocarbon-charged reservoirs that were sourced by an intrashelf basin include the Miocene Bombay High field, offshore India; the giant Jurassic (Arab-D) and Cretaceous (Shuaiba) reservoirs of the Arabian Shelf; the Lower Cretaceous Sunniland trend, South Florida basin; and the Permian-Pennsylvanian reservoirs surrounding the Tatum basin in southeastern New Mexico.

  16. Incorporating Stakeholder Decision Support Needs into an Integrated Regional Earth System Model

    SciTech Connect (OSTI)

    Rice, Jennie S.; Moss, Richard H.; Runci, Paul J.; Anderson, K. L.; Malone, Elizabeth L.

    2012-03-21T23:59:59.000Z

    A new modeling effort exploring the opportunities, constraints, and interactions between mitigation and adaptation at regional scale is utilizing stakeholder engagement in an innovative approach to guide model development and demonstration, including uncertainty characterization, to effectively inform regional decision making. This project, the integrated Regional Earth System Model (iRESM), employs structured stakeholder interactions and literature reviews to identify the most relevant adaptation and mitigation alternatives and decision criteria for each regional application of the framework. The information is used to identify important model capabilities and to provide a focus for numerical experiments. This paper presents the stakeholder research results from the first iRESM pilot region. The pilot region includes the Great Lakes Basin in the Midwest portion of the United States as well as other contiguous states. This geographic area (14 states in total) permits cohesive modeling of hydrologic systems while also providing gradients in climate, demography, land cover/land use, and energy supply and demand. The results from the stakeholder research indicate that iRESM should prioritize addressing adaptation alternatives in the water resources, urban infrastructure, and agriculture sectors, such as water conservation, expanded water quality monitoring, altered reservoir releases, lowered water intakes, urban infrastructure upgrades, increased electric power reserves in urban areas, and land use management/crop selection changes. Regarding mitigation alternatives, the stakeholder research shows a need for iRESM to focus on policies affecting the penetration of renewable energy technologies, and the costs and effectiveness of energy efficiency, bioenergy production, wind energy, and carbon capture and sequestration.

  17. Regional Seismic Signals from Chemical Explosions, Nuclear Explosions and Earthquakes: Results from the Arizona Source Phenomenology Experiment

    SciTech Connect (OSTI)

    Walter, W R; Gok, R; Mayeda, K; Sicherman, A; Bonner, J; Leidig, M

    2005-09-02T23:59:59.000Z

    Routine industrial mining explosions play two important roles in seismic nuclear monitoring research: (1) they are a source of background events that need to be discriminated from potential nuclear explosions; (2) as some of the only explosions occurring in the current de facto global moratoria on nuclear testing, their signals should be exploited to improve the calibration of seismic m monitoring systems. A common issue monitoring arising in both of these roles is our limited physical understanding of the causes behind observed differences and similarities in the seismic signals produced by routine industrial mining blasts and small underground nuclear tests. In 2003 a consortium (Weston, SMU, LLNL, LANL and UTEP) carried out a Source Phenomenology Experiment (SPE), a series of dedicated explosions designed to improve this physical understanding, particularly as it relates to seismic methods of discriminating between signals from three different source types: earthquakes, industrial blasts, and nuclear tests. Here we very briefly review prior field experimental work that examined the seismic relationships between these source types.

  18. Ecological Modelling 129 (2000) 209227 Quantification of the effects of nonpoint nutrient sources to

    E-Print Network [OSTI]

    Arhonditsis, George B.

    to coastal marine eutrophication: applications to a semi-enclosed gulf in the Mediterranean Sea G Elsevier Science B.V. All rights reserved. Keywords: Simulation modelling; Marine eutrophication; Nutrient of coastal marine eutrophication (Bo- rum, 1996). The sources of nutrients and organic matter for the coastal

  19. Monitoring Soil Moisture and Drought Using a Thermal TwoSource Energy Balance Model

    E-Print Network [OSTI]

    Kuligowski, Bob

    Monitoring Soil Moisture and Drought Using a Thermal TwoSource Energy Balance Model Christopher. In general, dry soil or stressed vegetation heats up more rapidly than wet soil or unstressed vegetation, using one dual polarized channel (either Cband or Xband) for the retrieval of soil moisture

  20. Impact of transport model errors on the global and regional methane emissions estimated by inverse modelling

    E-Print Network [OSTI]

    Locatelli, R.

    A modelling experiment has been conceived to assess the impact of transport model errors on methane emissions estimated in an atmospheric inversion system. Synthetic methane observations, obtained from 10 different model ...

  1. A Multi-Model Assessment of Regional Climate Disparities Caused by Solar Geoengineering

    E-Print Network [OSTI]

    Robock, Alan

    1 A Multi-Model Assessment of Regional Climate Disparities Caused by Solar Geoengineering Normal University, Beijing, China. 9 School of Engineering and Applied Sciences, Harvard University levels. G1 involves a reduction in solar irradiance to counteract the radiative forcing5 in abrupt4xCO2

  2. Polar-region distributions of Poynting flux: Global models compared with observations

    E-Print Network [OSTI]

    Lotko, William

    submitted to J. Atmospheric and Solar-Terrestrial Physics 10 June 2007 #12;model. The location and extent- mosphere is the primary sink for electromagnetic power generated by the solar wind energization of auroral- and cusp-region plasmas, this variable energy transfer accounts for upwards of 60

  3. Time series analysis of regional climate model performance Jason P. Evans

    E-Print Network [OSTI]

    Evans, Jason

    in Kansas, United States, including the First International Satellite Land Surface Climatology Project, both regional and global, has become apparent. Predictions of the energy and water balance to evapotranspiration and fails to close the energy budget. All of the models overestimate runoff and evapotranspiration

  4. Regional regression models of watershed suspended-sediment discharge for the eastern United States

    E-Print Network [OSTI]

    Vogel, Richard M.

    : Sediment transport Regression Water quality Ungaged GAGES SPARROW s u m m a r y Estimates of mean annual Streamflow (GAGES) database. The resulting regional regression models summarized for major US water resources contaminants including pesticides, met- als, and polycyclic aromatic hydrocarbons (PAHs) readily sorb

  5. Biophysical modeling of NO emissions from agricultural soils for use in regional

    E-Print Network [OSTI]

    Boyer, Edmond

    Biophysical modeling of NO emissions from agricultural soils for use in regional chemistry-transport and12 crop management practices, along with the resolution of the climate and soil input maps.13 14 and agronomic factors, including cropping practices, soil characteristics and cli-17 mate. Crop management

  6. Development of a model of an x-ray tube transmission source

    SciTech Connect (OSTI)

    Goda, Joetta M [Los Alamos National Laboratory; Ianakiev, Kiril D [Los Alamos National Laboratory; Moss, Cal E [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    In support of the development of an x-ray tube based source for transmission measurements of UF6 gas, we have developed a one-dimensional, spreadsheet-based model of the source. Starting with the spectrum produced by an x-ray tube we apply the linear attenuation coefficients for various notch filters, the aluminum pipe, and UF6 gas. This model allows calculation of the transmitted spectrum based on the type of filter, the thickness of the filter, the x-ray tube high voltage, the Al pipe thickness, and the UF6 gas pressure. The sensitivity of the magnitude of the transmission peak produced by the notch filter to any of these variables can be explored quickly and easily to narrow the choices for experimental measurements. To validate the spreadsheet based model, comparisons have been made to various experimental data.

  7. Conceptual model for regional radionuclide transport from a salt dome repository: a technical memorandum

    SciTech Connect (OSTI)

    Kier, R.S.; Showalter, P.A.; Dettinger, M.D.

    1980-05-30T23:59:59.000Z

    Disposal of high-level radioactive wastes is a major environmental problem influencing further development of nuclear energy in this country. Salt domes in the Gulf Coast Basin are being investigated as repository sites. A major concern is geologic and hydrologic stability of candidate domes and potential transport of radionuclides by groundwater to the biosphere prior to their degradation to harmless levels of activity. This report conceptualizes a regional geohydrologic model for transport of radionuclides from a salt dome repository. The model considers transport pathways and the physical and chemical changes that would occur through time prior to the radionuclides reaching the biosphere. Necessary, but unknown inputs to the regional model involve entry and movement of fluids through the repository dome and across the dome-country rock interface and the effect on the dome and surrounding strata of heat generated by the radioactive wastes.

  8. RSL: A parallel Runtime System Library for regional atmospheric models with nesting

    SciTech Connect (OSTI)

    Michalakes, J.G.

    1997-08-01T23:59:59.000Z

    RSL is a parallel runtime system library developed at Argonne National Laboratory that is tailored to regular-grid atmospheric models with mesh refinement in the form of two-way interacting nested grids. RSL provides high-level stencil and interdomain communication, irregular domain decomposition, automatic local/global index translation, distributed I/O, and dynamic load balancing. RSL was used with Fortran90 to parallelize a well-known and widely used regional weather model, the Penn State/NCAR Mesoscale model.

  9. Two-dimensional modeling of apparent resistivity pseudosections in the Cerro Prieto region

    SciTech Connect (OSTI)

    Vega, R.; Martinez, M.

    1981-01-01T23:59:59.000Z

    Using a finite-difference program (Dey, 1976) for two-dimensional modeling of apparent resistivity pseudosections obtained by different measuring arrays, four apparent resistivity pseudosections obtained at Cerro Prieto with a Schlumberger array by CFE personnel were modeled (Razo, 1978). Using geologic (Puente and de la Pena, 1978) and lithologic (Diaz, et al., 1981) data from the geothermal region, models were obtained which show clearly that, for the actual resistivity present in the zone, the information contained in the measured pseudosections is primarily due to the near-surface structure and does not show either the presence of the geothermal reservoir or the granitic basement which underlies it.

  10. Using Pre-Modeled Scenarios to Estimate Groundwater VOC Concentrations Resulting from Vadose Zone Sources

    SciTech Connect (OSTI)

    Oostrom, Martinus; Truex, Michael J.; Rice, Amy K.; Johnson, Christian D.; Carroll, Kenneth C.; Becker, Dave; Simon, Michelle A.

    2014-04-28T23:59:59.000Z

    Soil vapor extraction (SVE) is a prevalent remediation approach for volatile contaminants in the vadose zone. To support selection of an appropriate endpoint for the SVE remedy, an evaluation is needed to determine whether vadose zone contamination has been diminished sufficiently to protect groundwater. When vapor-phase transport is an important component of the overall contaminant fate and transport from a vadose zone source, the contaminant concentration expected in groundwater is controlled by a limited set of parameters, including specific site dimensions, vadose zone properties, and source characteristics. An approach was developed for estimating the contaminant concentration in groundwater resulting from a contaminant source in the vadose zone based on pre-modeling contaminant transport for a matrix of parameter value combinations covering a range of potential site conditions. An interpolation and scaling process are then applied to estimate groundwater impact for site-specific conditions.

  11. Wetland model in an earth systems modeling framework for regional environmental policy analysis

    E-Print Network [OSTI]

    Awadalla, Sirein Salah

    2011-01-01T23:59:59.000Z

    The objective of this research is to investigate incorporating a wetland component into a land energy and water fluxes model, the Community Land Model (CLM). CLM is the land fluxes component of the Integrated Global Systems ...

  12. Source characterization and modeling development for monoenergetic-proton radiography experiments on OMEGA

    SciTech Connect (OSTI)

    Manuel, M. J.-E.; Zylstra, A. B.; Rinderknecht, H. G.; Casey, D. T.; Rosenberg, M. J.; Sinenian, N.; Li, C. K.; Frenje, J. A.; Seguin, F. H.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

    2012-06-15T23:59:59.000Z

    A monoenergetic proton source has been characterized and a modeling tool developed for proton radiography experiments at the OMEGA [T. R. Boehly et al., Opt. Comm. 133, 495 (1997)] laser facility. Multiple diagnostics were fielded to measure global isotropy levels in proton fluence and images of the proton source itself provided information on local uniformity relevant to proton radiography experiments. Global fluence uniformity was assessed by multiple yield diagnostics and deviations were calculated to be {approx}16% and {approx}26% of the mean for DD and D{sup 3}He fusion protons, respectively. From individual fluence images, it was found that the angular frequencies of Greater-Than-Or-Equivalent-To 50 rad{sup -1} contributed less than a few percent to local nonuniformity levels. A model was constructed using the Geant4 [S. Agostinelli et al., Nuc. Inst. Meth. A 506, 250 (2003)] framework to simulate proton radiography experiments. The simulation implements realistic source parameters and various target geometries. The model was benchmarked with the radiographs of cold-matter targets to within experimental accuracy. To validate the use of this code, the cold-matter approximation for the scattering of fusion protons in plasma is discussed using a typical laser-foil experiment as an example case. It is shown that an analytic cold-matter approximation is accurate to within Less-Than-Or-Equivalent-To 10% of the analytic plasma model in the example scenario.

  13. Perspective on Advances in Resonance-Region Nuclear Modeling and Opportunities for Future Research

    SciTech Connect (OSTI)

    Dunn, Michael E [ORNL; Larson, Nancy M [ORNL; Derrien, Herve [ORNL; Leal, Luiz C [ORNL

    2007-01-01T23:59:59.000Z

    The advent of high-fidelity radiation-transport modeling capabilities, coupled with the need to analyze complex nuclear systems, has served to emphasize the importance of high-precision cross section data, including the associated covariance information. Due to the complex nature of resonance-region interactions, cross section data cannot be calculated directly from theory; rather, high-precision resonance-region cross section measurements must be made at facilities such as the Oak Ridge Electron Linear Accelerator (ORELA) at Oak Ridge National Laboratory (ORNL), Geel Electron Linear Accelerator (GELINA), Rensselaer Polytechnic Institute (RPI). To extract accurate cross section data from these measurements, detailed nuclear modeling of the measured data is performed to parameterize the cross section behavior in the resonance range. The objective of this paper is to highlight recent advances in resonance-region nuclear modeling with particular emphasis on the covariance analysis capabilities. Opportunities for future research are identified in an effort to stimulate further advances in the state of the art nuclear modeling capabilities.

  14. Analytical solutions for benchmarking cold regions subsurface water flow and energy transport models: One-dimensional soil thaw

    E-Print Network [OSTI]

    McKenzie, Jeffrey M.

    Analytical solutions for benchmarking cold regions subsurface water flow and energy transport Freezing and thawing a b s t r a c t Numerous cold regions water flow and energy transport models have of powerful simulators of cold regions subsurface water flow and energy transport have emerged in recent years

  15. Model of the heat source of the Cerro Prieto magma-hydrothermal system, Baja California, Mexico

    SciTech Connect (OSTI)

    Elders, W.A.; Bird, D.K.; Williams, A.E.; Schiffman, P.; Cox, B.

    1982-08-10T23:59:59.000Z

    Earlier studies at Cerro Prieto by UCR have led to the development of a qualitative model for field flow in the geothermal system before it was drilled and perturbed by production. Current efforts are directed towards numerical modelling of heat and mass transfer in the system in this undisturbed state. A two-dimensional model assumes that the heat sources were a single basalt/gabbro intrusion which provided heat to the system as it cooled. After compiling various information on the physical properties of the reservoir, the enthalpy contained in two 1cm thick section across the reservoir orthogonal to each other was calculated. Next various shapes, sizes and depths for the intrusion as initial conditions and boundary conditions for the calculation of heat transfer were considered. A family of numerical models which so far gives the best matches to the conditions observed in the field today have in common a funnel-shaped intrusion with a top 4km wide emplaced at a depth of 5km some 30,000 to 50,000 years ago, providing heat to the geothermal system. Numerical modelling is still in progress. Although none of the models so far computed may be a perfect match for the thermal history of the reservoir, they all indicate that the intrusive heat source is young, close and large.

  16. Blind Audio Source Separation using Short+Long Term AR Source Models and Iterative Itakura-Saito

    E-Print Network [OSTI]

    Gesbert, David

    the source separation can be performed satisfactorily, especially in clean environment, for example by using supported by its industrial partners: BMW, Cisco Systems, France T´el´ecom, Hitachi Europe, SFR, Sharp, ST

  17. Exact solution of the van der Waals model in the critical region

    E-Print Network [OSTI]

    Adriano Barra; Antonio Moro

    2014-12-05T23:59:59.000Z

    Inspired by the theory of nonlinear conservation laws, we propose a novel approach, in the framework of statistical mechanics, that naturally extends the van der Waals model to the critical region. Starting from an effective microscopic description, we derive the general functional form of its mean field partition function under the assumption named Isochoric Weights Thermodynamic ansatz. The condition that outside the critical region the model reproduces, in the thermodynamic limit, the classical van der Waals equation of state allows to fix uniquely the partition function. We show that isothermal curves develop a classical viscous shock which provides the exact analytical description of the first order gas-liquid transition of simple fluids. The solution obtained holds for finite number of particles and, in the thermodynamic limit, automatically encodes the Maxwell equal areas rule.

  18. Temperature fluctuations in H II regions: t2 for the two-phase model

    E-Print Network [OSTI]

    Y. Zhang; B. Ercolano; X. -W. Liu

    2007-01-05T23:59:59.000Z

    Aims: We investigate temperature fluctuations in H II regions in terms of a two-phase model, which assumes that the nebular gas consists of a hot and a cold phase. Methods: We derive general formulae for T([O III), the [O III] forbidden line temperature, and T(H I), the hydrogen Balmer jump temperature, in terms of the temperatures of the hot and cold phases, T_h and T_c. Results: For large temperature differences, the values of t2 required to account for the observed difference between T([O III]) and T(H I) are much lower than those deduced using the classical formulae that assume random and small amplitude temperature fluctuations. One should therefore be cautious when using a two-phase model to account for empirically derived $t^2$ values. We present a correction of a recent work by Giammanco & Beckman, who use a two-phase model to estimate the ionization rate of H II regions by cosmicrays. We show that a very small amount of cold gas is sufficient to account for t2 values typically inferred for H II regions.

  19. A transmission/escape probabilities model for neutral particle transport in the outer regions of a diverted tokamak

    SciTech Connect (OSTI)

    Stacey, W.M.

    1992-12-01T23:59:59.000Z

    A new computational model for neutral particle transport in the outer regions of a diverted tokamak plasma chamber is presented. The model is based on the calculation of transmission and escape probabilities using first-flight integral transport theory and the balancing of fluxes across the surfaces bounding the various regions. The geometrical complexity of the problem is included in precomputed probabilities which depend only on the mean free path of the region.

  20. Final Report on Hierarchical Coupled Modeling and Prediction of Regional Climate Change in the Atlantic Sector

    SciTech Connect (OSTI)

    Saravanan, Ramalingam [Texas A& M University

    2011-10-30T23:59:59.000Z

    During the course of this project, we have accomplished the following: a) Carried out studies of climate changes in the past using a hierarchy of intermediate coupled models (Chang et al., 2008; Wan et al 2009; Wen et al., 2010a,b) b) Completed the development of a Coupled Regional Climate Model (CRCM; Patricola et al., 2011a,b) c) Carried out studies testing hypotheses testing the origin of systematic errors in the CRCM (Patricola et al., 2011a,b) d) Carried out studies of the impact of air-sea interaction on hurricanes, in the context of barrier layer interactions (Balaguru et al)

  1. Modelling the chromosphere and transition region of Epsilon Eri (K2 V)

    E-Print Network [OSTI]

    S. A. Sim; C. Jordan

    2005-06-02T23:59:59.000Z

    Measurements of ultraviolet line fluxes from Space Telescope Imaging Spectrograph and Far-Ultraviolet Spectroscopic Explorer spectra of the K2-dwarf Epsilon Eri are reported. These are used to develop new emission measure distributions and semi-empirical atmospheric models for the chromosphere and lower transition region of the star. These models are the most detailed constructed to date for a main-sequence star other than the Sun. New ionisation balance calculations, which account for the effect of finite density on dielectronic recombination rates, are presented for carbon, nitrogen, oxygen and silicon. The results of these calculations are significantly different from the standard Arnaud & Rothenflug ion balance, particularly for alkali-like ions. The new atmospheric models are used to place constraints on possible First Ionisation Potential (FIP) related abundance variations in the lower atmosphere and to discuss limitations of single-component models for the interpretation of certain optically thick line fluxes.

  2. PM-10 Open Fugitive-Dust-Source computer model (for microcomputers). Model-Simulation

    SciTech Connect (OSTI)

    Elmore, L.

    1990-04-01T23:59:59.000Z

    The computer programs in the package are based on the material presented in the document, Control of Open Fugitive Dust Sources, EPA-450/3-88-008. The programs on these diskettes serve two purposes. Their primary purpose is to facilitate the process of data entry, allowing the user not only to enter and verify the data which he/she possesses, but also to access additional data which might not be readily available. The second purpose is to calculate emission rates for the particular source category selected using the data previously entered and verified. Software Description: The program is written in BASIC programming language for implementation on an IBM-PC/AT and compatible machines using DOS.2X or higher operating system. Hard disk with 5 1/4 inch disk drive or two disk drives, wide carriage printer (132-character) or printer capable of printing text in condensed mode required. Text editor or word processing program capable of manipulating ASCII or DOS text files is optional.

  3. Source- and Age-Resolved Mechanistic Air Quality Models: Model Development and Application in Southeast Texas 

    E-Print Network [OSTI]

    Zhang, Hongliang

    2012-07-16T23:59:59.000Z

    naphthalene (a), acenaphthene (b), acenaphthylene (c), fluorene (d), and phenanthrene (e) and relevant observation from 2007 to 2010 at DRPK. .............................. 122 Figure 5-5. Model predicted APAH1 and APAH2 concentrations as well as the APAHT...

  4. Modeling Study of Proposed Field Calibration Source Using K-40 Source and High-Z Targets for Sodium Iodide Detector

    E-Print Network [OSTI]

    Rogers, Jeremy 1987-

    2012-10-30T23:59:59.000Z

    isotope potassium-40 (40K) are not subject to these restrictions. Potassium-40’s beta spectrum and 1460.8 keV gamma ray can be used to induce K-shell fluorescence x rays in high-Z metals between 60 and 80 keV. A gamma ray calibration source is thus...

  5. A Multi-Model Analysis of the Regional and Sectoral Roles of Bioenergy in Near- and Long-Term CO2 Emissions

    SciTech Connect (OSTI)

    Calvin, Katherine V.; Wise, Marshall A.; Klein, David; McCollum, David; Tavoni, Massimo; van der Zwaan, Bob; Van Vuuren, Detlef

    2013-11-01T23:59:59.000Z

    We study the near term and the longer term the contribution of bioenergy in different LIMITS scenarios as modeled by the participating models in the LIMITS project. With These scenarios have proven useful for exploring a range of outcomes for bioenergy use in response to both regionally diverse near term policies and the transition to a longer-term global mitigation policy and target. The use of several models has provided a source of heterogeneity in terms of incorporating uncertain assumptions about future socioeconomics and technology, as well as different paradigms for how the world may respond to policies. The results have also highlighted the heterogeneity and versatility of bioenergy itself, with different types of resources and applications in several energy sectors. In large part due to this versatility, the contribution of bioenergy to climate mitigation is a robust response across all models, despite their differences.

  6. Solar surface emerging flux regions: a comparative study of radiative MHD modeling and Hinode SOT observations

    E-Print Network [OSTI]

    M. C. M. Cheung; M. Schuessler; T. D. Tarbell; A. M. Title

    2008-10-31T23:59:59.000Z

    We present results from numerical modeling of emerging flux regions on the solar surface. The modeling was carried out by means of 3D radiative MHD simulations of the rise of buoyant magnetic flux tubes through the convection zone and into the photosphere. Due to the strong stratification of the convection zone, the rise results in a lateral expansion of the tube into a magnetic sheet, which acts as a reservoir for small-scale flux emergence events at the scale of granulation. The interaction of the convective downflows and the rising magnetic flux undulates it to form serpentine field lines emerging into the photosphere. Observational characteristics including the pattern of emerging flux regions, the cancellation of surface flux and associated high speed downflows, the convective collapse of photospheric flux tubes, the appearance of anomalous darkenings, the formation of bright points and the possible existence of transient kilogauss horizontal fields are discussed in the context of new observations from the Hinode Solar Optical Telescope. Implications for the local helioseismology of emerging flux regions are also discussed.

  7. Achievements and deficiencies of nuclear models used for the design of spallation sources

    SciTech Connect (OSTI)

    Leray, S.; Boudard, A.; David, J. C.; Ducret, J. E.; Kezzar, K.; Le Gentil, E.; Lemaire, S.; Volant, C.; Yariv, Y. [CEA/Saclay, DAPNIA/SPhN, 91191 Gif-sur-Yvette, Cedex (France)

    2006-07-01T23:59:59.000Z

    High-energy transport codes are used in a large number of domains as spallation neutron sources or ADS design, space or medical applications. In these codes, nuclear models describing spallation reactions generate the necessary elementary cross-sections and characteristics of all the reaction products. During the last years, new high-quality experimental data have been collected leading to the development of more reliable spallation models, as the INCL4-ABLA combination of intranuclear cascade and de-excitation models, now available in MCNPX. However, remaining deficiencies have been identified, which can be of important consequences for applications, for instance in the prediction of damage. They generally originate from not well understood physics mechanisms. To solve these problems more constraining experiments are now being carried out, which allow a deeper understanding of the reaction mechanisms, in particular for the de-excitation stage. Recent improvements of INCL4 are presented. Impact for applications is discussed. (authors)

  8. Modeling & analysis of criticality-induced severe accidents during refueling for the Advanced Neutron Source Reactor

    SciTech Connect (OSTI)

    Georgevich, V.; Kim, S.H.; Taleyarkhan, R.P.; Jackson, S.

    1992-10-01T23:59:59.000Z

    This paper describes work done at the Oak Ridge National Laboratory (ORNL) for evaluating the potential and resulting consequences of a hypothetical criticality accident during refueling of the 330-MW Advanced Neutron Source (ANS) research reactor. The development of an analytical capability is described. Modeling and problem formulation were conducted using concepts of reactor neutronic theory for determining power level escalation, coupled with ORIGEN and MELCOR code simulations for radionuclide buildup and containment transport Gaussian plume transport modeling was done for determining off-site radiological consequences. Nuances associated with modeling this blast-type scenario are described. Analysis results for ANS containment response under a variety of postulated scenarios and containment failure modes are presented. It is demonstrated that individuals at the reactor site boundary will not receive doses beyond regulatory limits for any of the containment configurations studied.

  9. Impact of Agricultural Practice on Regional Climate in a CoupledLand Surface Mesoscale Model

    SciTech Connect (OSTI)

    Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.

    2004-07-01T23:59:59.000Z

    The land surface has been shown to form strong feedbacks with climate due to linkages between atmospheric conditions and terrestrial ecosystem exchanges of energy, momentum, water, and trace gases. Although often ignored in modeling studies, land management itself may form significant feedbacks. Because crops are harvested earlier under drier conditions, regional air temperature, precipitation, and soil moisture, for example, affect harvest timing, particularly of rain-fed crops. This removal of vegetation alters the land surface characteristics and may, in turn, affect regional climate. We applied a coupled climate(MM5) and land-surface (LSM1) model to examine the effects of early and late winter wheat harvest on regional climate in the Department of Energy Atmospheric Radiation Measurement (ARM) Climate Research Facility in the Southern Great Plains, where winter wheat accounts for 20 percent of the land area. Within the winter wheat region, simulated 2 m air temperature was 1.3 C warmer in the Early Harvest scenario at mid-day averaged over the two weeks following harvest. Soils in the harvested area were drier and warmer in the top 10 cm and wetter in the 10-20 cm layer. Midday soils were 2.5 C warmer in the harvested area at mid-day averaged over the two weeks following harvest. Harvest also dramatically altered latent and sensible heat fluxes. Although differences between scenarios diminished once both scenarios were harvested, the short-term impacts of land management on climate were comparable to those from land cover change demonstrated in other studies.

  10. IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan DYNAMIC MODELING OF AN AIR SOURCE HEAT PUMP WATER

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    SOURCE HEAT PUMP WATER HEATER Farouk Fardoun, Associate Professor, Department of Industrial Engineering of an air source heat pump water heater (ASHPWH). The mathematical model consists of submodels of the basic countries such as Lebanon, electric water heaters are often used to generate hot water. Electric water

  11. Regional groundwater flow model for C, K. L. and P reactor areas, Savannah River Site, Aiken, SC

    SciTech Connect (OSTI)

    Flach, G.P.

    2000-02-11T23:59:59.000Z

    A regional groundwater flow model encompassing approximately 100 mi2 surrounding the C, K, L, and P reactor areas has been developed. The reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department. The model provides a quantitative understanding of groundwater flow on a regional scale within the near surface aquifers and deeper semi-confined to confined aquifers. The model incorporates historical and current field characterization data up through Spring 1999. Model preprocessing is automated so that future updates and modifications can be performed quickly and efficiently. The CKLP regional reactor model can be used to guide characterization, perform scoping analyses of contaminant transport, and serve as a common base for subsequent finer-scale transport and remedial/feasibility models for each reactor area.

  12. Regional scale cropland carbon budgets: evaluating a geospatial agricultural modeling system using inventory data

    SciTech Connect (OSTI)

    Zhang, Xuesong; Izaurralde, Roberto C.; Manowitz, David H.; Sahajpal, Ritvik; West, Tristram O.; Thomson, Allison M.; Xu, Min; Zhao, Kaiguang; LeDuc, Stephen D.; Williams, Jimmy R.

    2015-01-01T23:59:59.000Z

    Accurate quantification and clear understanding of regional scale cropland carbon (C) cycling is critical for designing effective policies and management practices that can contribute toward stabilizing atmospheric CO2 concentrations. However, extrapolating site-scale observations to regional scales represents a major challenge confronting the agricultural modeling community. This study introduces a novel geospatial agricultural modeling system (GAMS) exploring the integration of the mechanistic Environmental Policy Integrated Climate model, spatially-resolved data, surveyed management data, and supercomputing functions for cropland C budgets estimates. This modeling system creates spatially-explicit modeling units at a spatial resolution consistent with remotely-sensed crop identification and assigns cropping systems to each of them by geo-referencing surveyed crop management information at the county or state level. A parallel computing algorithm was also developed to facilitate the computationally intensive model runs and output post-processing and visualization. We evaluated GAMS against National Agricultural Statistics Service (NASS) reported crop yields and inventory estimated county-scale cropland C budgets averaged over 2000–2008. We observed good overall agreement, with spatial correlation of 0.89, 0.90, 0.41, and 0.87, for crop yields, Net Primary Production (NPP), Soil Organic C (SOC) change, and Net Ecosystem Exchange (NEE), respectively. However, we also detected notable differences in the magnitude of NPP and NEE, as well as in the spatial pattern of SOC change. By performing crop-specific annual comparisons, we discuss possible explanations for the discrepancies between GAMS and the inventory method, such as data requirements, representation of agroecosystem processes, completeness and accuracy of crop management data, and accuracy of crop area representation. Based on these analyses, we further discuss strategies to improve GAMS by updating input data and by designing more efficient parallel computing capability to quantitatively assess errors associated with the simulation of C budget components. The modularized design of the GAMS makes it flexible to be updated and adapted for different agricultural models so long as they require similar input data, and to be linked with socio-economic models to understand the effectiveness and implications of diverse C management practices and policies.

  13. MODELING SUPER-FAST MAGNETOSONIC WAVES OBSERVED BY SDO IN ACTIVE REGION FUNNELS

    SciTech Connect (OSTI)

    Ofman, L. [Department of Physics, Catholic University of America, Washington, DC 20064 (United States); Liu, W.; Title, A.; Aschwanden, M. [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)

    2011-10-20T23:59:59.000Z

    Recently, quasi-periodic, rapidly propagating waves have been observed in extreme ultraviolet by the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) instrument in about 10 flare/coronal mass ejection (CME) events thus far. A typical example is the 2010 August 1 C3.2 flare/CME event that exhibited arc-shaped wave trains propagating in an active region (AR) magnetic funnel with {approx}5% intensity variations at speeds in the range of 1000-2000 km s{sup -1}. The fast temporal cadence and high sensitivity of AIA enabled the detection of these waves. We identify them as fast magnetosonic waves driven quasi-periodically at the base of the flaring region and develop a three-dimensional MHD model of the event. For the initial state we utilize the dipole magnetic field to model the AR and include gravitationally stratified density at coronal temperature. At the coronal base of the AR, we excite the fast magnetosonic wave by periodic velocity pulsations in the photospheric plane confined to a funnel of magnetic field lines. The excited fast magnetosonic waves have similar amplitude, wavelength, and propagation speeds as the observed wave trains. Based on the simulation results, we discuss the possible excitation mechanism of the waves, their dynamical properties, and the use of the observations for coronal MHD seismology.

  14. A nanoflare model for active region radiance: application of artificial neural networks

    E-Print Network [OSTI]

    M. Bazarghan; H. Safari; D. E. Innes; E. Karami; S. K. Solanki

    2008-12-20T23:59:59.000Z

    Context. Nanoflares are small impulsive bursts of energy that blend with and possibly make up much of the solar background emission. Determining their frequency and energy input is central to understanding the heating of the solar corona. One method is to extrapolate the energy frequency distribution of larger individually observed flares to lower energies. Only if the power law exponent is greater than 2, is it considered possible that nanoflares contribute significantly to the energy input. Aims. Time sequences of ultraviolet line radiances observed in the corona of an active region are modelled with the aim of determining the power law exponent of the nanoflare energy distribution. Methods. A simple nanoflare model based on three key parameters (the flare rate, the flare duration time, and the power law exponent of the flare energy frequency distribution) is used to simulate emission line radiances from the ions Fe XIX, Ca XIII, and Si iii, observed by SUMER in the corona of an active region as it rotates around the east limb of the Sun. Light curve pattern recognition by an Artificial Neural Network (ANN) scheme is used to determine the values. Results. The power law exponents, alpha 2.8, 2.8, and 2.6 for Fe XIX, Ca XIII, and Si iii respectively. Conclusions. The light curve simulations imply a power law exponent greater than the critical value of 2 for all ion species. This implies that if the energy of flare-like events is extrapolated to low energies, nanoflares could provide a significant contribution to the heating of active region coronae.

  15. A One-Dimensional (1-D) Three-Region Model for a Bubbling Fluidized-Bed Adsorber

    SciTech Connect (OSTI)

    Lee, Andrew; Miller, David C.

    2012-01-01T23:59:59.000Z

    A general one-dimensional (1-D), three-region model for a bubbling fluidized-bed adsorber with internal heat exchangers has been developed. The model can predict the hydrodynamics of the bed and provides axial profiles for all temperatures, concentrations, and velocities. The model is computationally fast and flexible and allows for any system of adsorption and desorption reactions to be modeled, making the model applicable to any adsorption process. The model has been implemented in both gPROMS and Aspen Custom Modeler, and the behavior of the model has been verified.

  16. On an improved sub-regional water resources management representation for integration into earth system models

    SciTech Connect (OSTI)

    Voisin, Nathalie; Li, Hongyi; Ward, Duane L.; Huang, Maoyi; Wigmosta, Mark S.; Leung, Lai-Yung R.

    2013-09-30T23:59:59.000Z

    Human influence on the hydrologic cycle includes regulation and storage, consumptive use and overall redistribution of water resources in space and time. Representing these processes is essential for applications of earth system models in hydrologic and climate predictions, as well as impact studies at regional to global scales. Emerging large-scale research reservoir models use generic operating rules that are flexible for coupling with earth system models. Those generic operating rules have been successful in reproducing the overall regulated flow at large basin scales. This study investigates the uncertainties of the reservoir models from different implementations of the generic operating rules using the complex multi-objective Columbia River Regulation System in northwestern United States as an example to understand their effects on not only regulated flow but also reservoir storage and fraction of the demand that is met. Numerical experiments are designed to test new generic operating rules that combine storage and releases targets for multi-purpose reservoirs and to compare the use of reservoir usage priorities, withdrawals vs. consumptive demand, as well as natural vs. regulated mean flow for calibrating operating rules. Overall the best performing implementation is the use of the combined priorities (flood control storage targets and irrigation release targets) operating rules calibrated with mean annual natural flow and mean monthly withdrawals. The challenge of not accounting for groundwater withdrawals, or on the contrary, assuming that all remaining demand is met through groundwater extractions, is discussed.

  17. A Software System for Modeling and Controlling Accelerator Physics Parameters at the Advanced Light Source

    E-Print Network [OSTI]

    Schachinger, L.C.

    2011-01-01T23:59:59.000Z

    and Controlling Accelerator Physics Parameters at theLight Source for accelerator physics studies and accelerator

  18. Journal of the Meteorological Society of Japan, Vol. 82, No. 6, pp. 1599--1628, 2004 1599 Regional Climate Modeling: Progress, Challenges, and Prospects

    E-Print Network [OSTI]

    Wang, Yuqing

    , and development of regional earth system models. It is believed that with the demonstrated credibility of RCMs

  19. Journal of Power Sources 162 (2006) 388399 Model-based condition monitoring of PEM fuel cell using

    E-Print Network [OSTI]

    Ding, Yu

    2006-01-01T23:59:59.000Z

    Journal of Power Sources 162 (2006) 388­399 Model-based condition monitoring of PEM fuel cell using of polymer electrolyte membrane (PEM) fuel cell systems, temporary faults in such systems still might occur/uncertainty of the fuel cell system, and the measurement noise. In this research, we propose a model-based condition

  20. Journal of Power Sources 164 (2007) 189195 Modeling water transport in liquid feed direct methanol fuel cells

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Journal of Power Sources 164 (2007) 189­195 Modeling water transport in liquid feed direct methanol management in direct methanol fuel cells (DMFCs) is very critical and complicated because of many interacting rights reserved. Keywords: Direct methanol fuel cell; Water transport; Mathematical modeling; Three

  1. An image-based four-source surface energy balance model to estimate crop evapotranspiration from solar

    E-Print Network [OSTI]

    Boyer, Edmond

    An image-based four-source surface energy balance model to estimate crop evapotranspiration from solar reflectance/thermal emission data (SEB-4S) Olivier Merlin,a , Jonas Chirouzea , Albert Oliosob, 84000 Avignon, France Abstract A remote sensing-based surface energy balance model is developed

  2. Nonlinear force-free models for the solar corona I. Two active regions with very different structure

    E-Print Network [OSTI]

    S. Regnier; E. R. Priest

    2007-03-29T23:59:59.000Z

    With the development of new instrumentation providing measurements of solar photospheric vector magnetic fields, we need to develop our understanding of the effects of current density on coronal magnetic field configurations. The object is to understand the diverse and complex nature of coronal magnetic fields in active regions using a nonlinear force-free model. From the observed photospheric magnetic field we derive the photospheric current density for two active regions: one is a decaying active region with strong currents (AR8151), and the other is a newly emerged active region with weak currents (AR8210). We compare the three-dimensional structure of the magnetic fields for both active region when they are assumed to be either potential or nonlinear force-free. The latter is computed using a Grad-Rubin vector-potential-like numerical scheme. A quantitative comparison is performed in terms of the geometry, the connectivity of field lines, the magnetic energy and the magnetic helicity content. For the old decaying active region the connectivity and geometry of the nonlinear force-free model include strong twist and strong shear and are very different from the potential model. The twisted flux bundles store magnetic energy and magnetic helicity high in the corona (about 50 Mm). The newly emerged active region has a complex topology and the departure from a potential field is small, but the excess magnetic energy is stored in the low corona and is enough to trigger powerful flares.

  3. Regional climate effects of irrigation and urbanization in thewestern united states: a model intercomparison

    SciTech Connect (OSTI)

    Snyder, M.A.; Kueppers, L.M.; Sloan, L.C.; Cavan, D.C.; Jin, J.; Kanamaru, H.; Miller, N.L.; Tyree, M.; Du, H.; Weare, B.

    2006-05-01T23:59:59.000Z

    In the western United States, more than 30,500 square miles has been converted to irrigated agriculture and urban areas. This study compares the climate responses of four regional climate models (RCMs) to these past land-use changes. The RCMs used two contrasting land cover distributions: potential natural vegetation, and modern land cover that includes agriculture and urban areas. Three of the RCMs represented irrigation by supplementing soil moisture, producing large decreases in August mean (-2.5 F to -5.6 F) and maximum (-5.2 F to -10.1 F) 2-meter temperatures where natural vegetation was converted to irrigated agriculture. Conversion to irrigated agriculture also resulted in large increases in relative humidity (9 percent 36 percent absolute change). Only one of the RCMs produced increases in summer minimum temperature. Converting natural vegetation to urban land cover produced modest but discernable climate effects in all models, with the magnitude of the effects dependent upon the preexisting vegetation type. Overall, the RCM results indicate that land use change impacts are most pronounced during the summer months, when surface heating is strongest and differences in surface moisture between irrigated land and natural vegetation are largest. The irrigation effect on summer maximum temperatures is comparable in magnitude (but opposite in sign) to predicted future temperature change due to increasing greenhouse gas concentrations.

  4. Exploring the connection between coronal and footpoint sources in a thin-thick target solar flare model

    E-Print Network [OSTI]

    Marina Battaglia; Arnold O. Benz

    2007-02-12T23:59:59.000Z

    Context: Hard X-ray emission of coronal sources in solar flares has been observed and studied since its discovery in Yohkoh observations. Several models have been proposed to explain the physical mechanisms causing this emission and the relations between those sources and simultaneously observed footpoint sources. Aims: We investigate and test one of the models (intermediate thin-thick target model) developed on the basis of Yohkoh observations. The model makes precise predictions on the shape of coronal and footpoint spectra and the relations between them, that can be tested with new instruments such as RHESSI. Methods: RHESSI observations of well observed events are studied in imaging and spectroscopy and compared to the predictions from the intermediate thin-thick target model. Results: The results indicate that such a simple model cannot account for the observed relations between the non-thermal spectra of coronal and footpoint sources. Including non-collisional energy loss of the electrons in the flare loop due to an electric field can solve most of the inconsistencies.

  5. USING A DIFFERENTIAL EMISSION MEASURE AND DENSITY MEASUREMENTS IN AN ACTIVE REGION CORE TO TEST A STEADY HEATING MODEL

    SciTech Connect (OSTI)

    Winebarger, Amy R. [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States); Schmelz, Joan T. [Physics Department, University of Memphis, Memphis, TN 38152 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Saar, Steve H.; Kashyap, Vinay L., E-mail: amy.r.winebarger@nasa.gov [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2011-10-10T23:59:59.000Z

    The frequency of heating events in the corona is an important constraint on the coronal heating mechanisms. Observations indicate that the intensities and velocities measured in active region cores are effectively steady, suggesting that heating events occur rapidly enough to keep high-temperature active region loops close to equilibrium. In this paper, we couple observations of active region (AR) 10955 made with the X-Ray Telescope and the EUV Imaging Spectrometer on board Hinode to test a simple steady heating model. First we calculate the differential emission measure (DEM) of the apex region of the loops in the active region core. We find the DEM to be broad and peaked around 3 MK. We then determine the densities in the corresponding footpoint regions. Using potential field extrapolations to approximate the loop lengths and the density-sensitive line ratios to infer the magnitude of the heating, we build a steady heating model for the active region core and find that we can match the general properties of the observed DEM for the temperature range of 6.3 < log T < 6.7. This model, for the first time, accounts for the base pressure, loop length, and distribution of apex temperatures of the core loops. We find that the density-sensitive spectral line intensities and the bulk of the hot emission in the active region core are consistent with steady heating. We also find, however, that the steady heating model cannot address the emission observed at lower temperatures. This emission may be due to foreground or background structures, or may indicate that the heating in the core is more complicated. Different heating scenarios must be tested to determine if they have the same level of agreement.

  6. A regional economic impact model for identifying the relationship between transportation investments and economic development

    E-Print Network [OSTI]

    Freyre, German Eleodoro

    1989-01-01T23:59:59.000Z

    Allocation of Project Investment Calculation for Efficiency Savings Calculation of Mobility Savings Calculation of Safety Savings FHWA-47 Form Program Structure Basic Procedures Regional Impacts by the Amount Invested in an Urban Interstate System... Regional Impacts by the Amount Invested in an Urban Primary System Regional Impacts by the Amount Invested in an Rural Interstate System Regional Impacts by the Amount Invested in an Rural Primary System 15 17 18 20 . 23 27 56 58 95 96 97...

  7. Reactor physics methods, models, and applications used to support the conceptual design of the Advanced Neutron Source

    SciTech Connect (OSTI)

    Gehin, J.C.; Worley, B.A.; Renier, J.P. [Oak Ridge National Lab., TN (United States); Wemple, C.A.; Jahshan, S.N.; Ryskammp, J.M. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-08-01T23:59:59.000Z

    This report summarizes the neutronics analysis performed during 1991 and 1992 in support of characterization of the conceptual design of the Advanced Neutron Source (ANS). The methods used in the analysis, parametric studies, and key results supporting the design and safety evaluations of the conceptual design are presented. The analysis approach used during the conceptual design phase followed the same approach used in early ANS evaluations: (1) a strong reliance on Monte Carlo theory for beginning-of-cycle reactor performance calculations and (2) a reliance on few-group diffusion theory for reactor fuel cycle analysis and for evaluation of reactor performance at specific time steps over the fuel cycle. The Monte Carlo analysis was carried out using the MCNP continuous-energy code, and the few- group diffusion theory calculations were performed using the VENTURE and PDQ code systems. The MCNP code was used primarily for its capability to model the reflector components in realistic geometries as well as the inherent circumvention of cross-section processing requirements and use of energy-collapsed cross sections. The MCNP code was used for evaluations of reflector component reactivity effects and of heat loads in these components. The code was also used as a benchmark comparison against the diffusion-theory estimates of key reactor parameters such as region fluxes, control rod worths, reactivity coefficients, and material worths. The VENTURE and PDQ codes were used to provide independent evaluations of burnup effects, power distributions, and small perturbation worths. The performance and safety calculations performed over the subject time period are summarized, and key results are provided. The key results include flux and power distributions over the fuel cycle, silicon production rates, fuel burnup rates, component reactivities, control rod worths, component heat loads, shutdown reactivity margins, reactivity coefficients, and isotope production rates.

  8. Environment and the Lifetime of Tropical Deep Convection in a Cloud-Permitting Regional Model Simulation

    SciTech Connect (OSTI)

    Hagos, Samson M.; Feng, Zhe; McFarlane, Sally A.; Leung, Lai-Yung R.

    2013-08-01T23:59:59.000Z

    By applying a cloud tracking algorithm to tropical convective systems simulated by a regional high resolution model, the study documents environmental conditions before and after convective systems are initiated over ocean and land by following them during their lifetime. The comparative roles of various environmental fields in affecting the lifetime of convection are also quantified. The statistics of lifetime, maximum area, propagation speed and direction of the simulated deep convection agrees well with geostationary satellite observations. Over ocean, convective systems enhance surface fluxes through the associated wind gusts as well as cooling and drying of the boundary layer. A significant relationship is found between the mean surface fluxes during their lifetime and the longevity of the systems which in turn is related to the initial intensity of the moist updraft and to a lesser extent upper level shear. Over land, on the other hand, convective activity suppresses surface fluxes through cloud cover and the lifetime of convection is related to the upper level shear during their lifetime and strength of the heat fluxes several hours before the initiation of convection. For systems of equal lifetime, those over land are significantly more intense than those over ocean especially during early stages of their lifetime.

  9. KINETIC MODELING OF PARTICLE ACCELERATION IN A SOLAR NULL-POINT RECONNECTION REGION

    SciTech Connect (OSTI)

    Baumann, G.; Haugbolle, T.; Nordlund, A., E-mail: gbaumann@nbi.ku.dk [Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark)

    2013-07-10T23:59:59.000Z

    The primary focus of this paper is on the particle acceleration mechanism in solar coronal three-dimensional reconnection null-point regions. Starting from a potential field extrapolation of a Solar and Heliospheric Observatory (SOHO) magnetogram taken on 2002 November 16, we first performed magnetohydrodynamics (MHD) simulations with horizontal motions observed by SOHO applied to the photospheric boundary of the computational box. After a build-up of electric current in the fan plane of the null point, a sub-section of the evolved MHD data was used as initial and boundary conditions for a kinetic particle-in-cell model of the plasma. We find that sub-relativistic electron acceleration is mainly driven by a systematic electric field in the current sheet. A non-thermal population of electrons with a power-law distribution in energy forms in the simulated pre-flare phase, featuring a power-law index of about -1.78. This work provides a first step toward bridging the gap between macroscopic scales on the order of hundreds of Mm and kinetic scales on the order of centimeter in the solar corona, and explains how to achieve such a cross-scale coupling by utilizing either physical modifications or (equivalent) modifications of the constants of nature. With their exceptionally high resolution-up to 135 billion particles and 3.5 billion grid cells of size 17.5 km-these simulations offer a new opportunity to study particle acceleration in solar-like settings.

  10. Exact solution of the van der Waals model in the critical region

    E-Print Network [OSTI]

    Adriano Barra; Antonio Moro

    2015-05-01T23:59:59.000Z

    The celebrated van der Waals model describes simple fluids in the thermodynamic limit and predicts the existence of a critical point associated to the gas-liquid phase transition. However the behaviour of critical isotherms according to the equation of state, where a gas-liquid phase transition occurs, significantly departs from experimental observations. The correct critical isotherms are heuristically re-established via the Maxwell equal areas rule. A long standing open problem in mean field theory is concerned with the analytic description of van der Waals isotherms for a finite size system that is consistent, in the thermodynamic limit, with the Maxwell prescription. Inspired by the theory of nonlinear conservation laws, we propose a novel mean field approach, based on statistical mechanics, that allows to calculate the van der Waals partition function for a system of large but finite number of particles $N$. Our partition function naturally extends to the whole space of thermodynamic variables, reproduces, in the thermodynamic limit $N\\to \\infty$, the classical results outside the critical region and automatically encodes Maxwell's prescription. We show that isothermal curves evolve in the space of thermodynamic variables like nonlinear breaking waves and the criticality is explained as the mechanism of formation of a classical hydrodynamic shock.

  11. Modification of the TASMIP x-ray spectral model for the simulation of microfocus x-ray sources

    SciTech Connect (OSTI)

    Sisniega, A.; Vaquero, J. J., E-mail: juanjose.vaquero@uc3m.es [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Desco, M. [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain) [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Madrid ES28911 (Spain); Instituto de Investigación Sanitaria Gregorio Marañón, Madrid ES28007 (Spain); Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid ES28029 (Spain)

    2014-01-15T23:59:59.000Z

    Purpose: The availability of accurate and simple models for the estimation of x-ray spectra is of great importance for system simulation, optimization, or inclusion of photon energy information into data processing. There is a variety of publicly available tools for estimation of x-ray spectra in radiology and mammography. However, most of these models cannot be used directly for modeling microfocus x-ray sources due to differences in inherent filtration, energy range and/or anode material. For this reason the authors propose in this work a new model for the simulation of microfocus spectra based on existing models for mammography and radiology, modified to compensate for the effects of inherent filtration and energy range. Methods: The authors used the radiology and mammography versions of an existing empirical model [tungsten anode spectral model interpolating polynomials (TASMIP)] as the basis of the microfocus model. First, the authors estimated the inherent filtration included in the radiology model by comparing the shape of the spectra with spectra from the mammography model. Afterwards, the authors built a unified spectra dataset by combining both models and, finally, they estimated the parameters of the new version of TASMIP for microfocus sources by calibrating against experimental exposure data from a microfocus x-ray source. The model was validated by comparing estimated and experimental exposure and attenuation data for different attenuating materials and x-ray beam peak energy values, using two different x-ray tubes. Results: Inherent filtration for the radiology spectra from TASMIP was found to be equivalent to 1.68 mm Al, as compared to spectra obtained from the mammography model. To match the experimentally measured exposure data the combined dataset required to apply a negative filtration of about 0.21 mm Al and an anode roughness of 0.003 mm W. The validation of the model against real acquired data showed errors in exposure and attenuation in line with those reported for other models for radiology or mammography. Conclusions: A new version of the TASMIP model for the estimation of x-ray spectra in microfocus x-ray sources has been developed and validated experimentally. Similarly to other versions of TASMIP, the estimation of spectra is very simple, involving only the evaluation of polynomial expressions.

  12. Physical and chemical properties of the regional mixed layer of Mexico's Megapolis – Part II: Evaluation of measured and modeled trace gases and particle size distributions

    SciTech Connect (OSTI)

    Ochoa, Carlos; Baumgardner, Darrel; Grutter, M.; Allan, James D.; Fast, Jerome D.; Rappengluck, B.

    2012-10-31T23:59:59.000Z

    This study extends the work of Baumgardner et al. (2009) in which measurements of trace gases and particles at a remote, high-altitude mountain site 60 km from Mexico City were analyzed with respect to the origin of air masses. In the current evaluation, the temperature, water vapor, ozone (O3), carbon monoxide (CO), acyl peroxy nitrate (APN) and particle size distributions (PSDs) of the mass concentrations of sulfate, nitrate, ammonium and organic mass (OM) were simulated with the WRF-Chem chemical transport model and compared with the measurements at the mountain site. The model prediction of the diurnal trends of the gases were well correlated with the measurements before the regional boundary layer reached the measurement site but underestimated the concentrations after that time. The differences are caused by an overly rapid growth of the boundary layer by the model with too much dilution. There also appears to be more O3 produced by photochemical production, downwind of the emission sources, than predicted by the model. The measured and modeled PSDs compare very well with respect to their general shape and diameter of the peak concentrations. The spectra are log normally distributed with most of the mass in the accumulation mode and the geometric diameter centered at 200 ±20 nm, with little observed or predicted change with respect to the origin of the air mass or the time when the RBL is above the Altzomoni research. Only the total mass changed with time and air mass origin. The invariability of the average diameter of the accumulation mode suggests that there is very little growth of the particles by condensation or coagulation after six hours of aging downwind of the major sources of anthropogenic emissions in Mexico’s Megapolis.

  13. NON-LTE MODEL ATMOSPHERE ANALYSIS OF THE LARGE MAGELLANIC CLOUD SUPERSOFT X-RAY SOURCE CAL 83

    E-Print Network [OSTI]

    Audard, Marc

    NON-LTE MODEL ATMOSPHERE ANALYSIS OF THE LARGE MAGELLANIC CLOUD SUPERSOFT X-RAY SOURCE CAL 83 Magellanic Cloud. Taken with a 16 month in- terval, the Chandra and XMM-Newton spectra are very similar. They reveal a very rich absorption-line spectrum from the hot white dwarf photosphere but no spectral

  14. Effect of grid size on runoff and soil moisture for a variable-source-area hydrology model

    E-Print Network [OSTI]

    Walter, M.Todd

    landscapes are dependent on the distribution and pattern of soil moisture and water transport. In this paper for efficient manage- ment of water quality [U.S. Environmental Protection Agency, 1994, 1995, 1996Effect of grid size on runoff and soil moisture for a variable-source-area hydrology model Wen

  15. ONE-DIMENSIONAL MODELING FOR TEMPERATURE-DEPENDENT UPFLOW IN THE DIMMING REGION OBSERVED BY HINODE/EUV IMAGING SPECTROMETER

    SciTech Connect (OSTI)

    Imada, S.; Shimizu, T. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara-shi, Kanagawa 252-5210 (Japan); Hara, H.; Watanabe, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka-shi, Tokyo 181-8588 (Japan); Murakami, I. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Harra, L. K. [UCL-Mullard Space Science Laboratory, Holmbury St Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Zweibel, E. G. [Department of Astronomy, University of Wisconsin-Madison, 475 N Charter Street, Madison, WI 53706 (United States)

    2011-12-10T23:59:59.000Z

    We previously found a temperature-dependent upflow in the dimming region following a coronal mass ejection observed by the Hinode EUV Imaging Spectrometer (EIS). In this paper, we reanalyzed the observations along with previous work on this event and provided boundary conditions for modeling. We found that the intensity in the dimming region dramatically drops within 30 minutes from the flare onset, and the dimming region reaches the equilibrium stage after {approx}1 hr. The temperature-dependent upflows were observed during the equilibrium stage by EIS. The cross-sectional area of the flux tube in the dimming region does not appear to expand significantly. From the observational constraints, we reconstructed the temperature-dependent upflow by using a new method that considers the mass and momentum conservation law and demonstrated the height variation of plasma conditions in the dimming region. We found that a super-radial expansion of the cross-sectional area is required to satisfy the mass conservation and momentum equations. There is a steep temperature and velocity gradient of around 7 Mm from the solar surface. This result may suggest that the strong heating occurred above 7 Mm from the solar surface in the dimming region. We also showed that the ionization equilibrium assumption in the dimming region is violated, especially in the higher temperature range.

  16. Full-fuel-cycle approach to vehicle emissions modeling: A case study of gasoline in the southeastern region of the United States

    SciTech Connect (OSTI)

    Bell, S.R.; Gupta, M. [Univ. of Alabama, Tuscaloosa, AL (United States); Greening, L.A. [Lawrence Berkeley Lab., CA (United States)

    1995-09-01T23:59:59.000Z

    The use of full-fuel-cycle analysis as a scientific, economic, and policy tool for the evaluation of alternative sources of transportation energy has become increasingly widespread. However, consistent methods for performance of these types of analyses are only now becoming recognized and utilized. The work presented here provides a case study of full-fuel-cycle analysis methods applied to the evaluation of gasoline in the southeastern region of the United States. Results of the study demonstrate the significance of nonvehicle processes, such as fuel refining, in terms of energy expenditure and emissions production. Unique to this work is the application of the MOBILE5 mobile emissions model in the full-fuel-cycle analysis. Estimates of direct and indirect greenhouse gas production are also presented and discussed using the full-fuel-cycle analysis method.

  17. A Marked Point Process Model for the Source Proximity E ect in the Indoor Environment 1

    E-Print Network [OSTI]

    West, Mike

    indoor air quality monitors arise because of the source proximity e#11;ect, in which pollutant sources. McBride Abstract In indoor air quality studies, discrepancies between personal and station- ary Science Foundation Graduate Fellowship as well as the Center for Indoor Air Research. The author thanks

  18. Statistical representation of clouds in a regional model and the impact on the diurnal cycle of convection during Tropical

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    water static energy. Application of the parameterization in a regional model during a 30-day period of the Tropical Convection, Cirrus and Nitrogen Oxides (TROCCINOX) experiment over southern Brazil demonstrates of cloud mass at tropospheric inversions (e.g., trade wind inversion, melting level, tropo- pause

  19. Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II: Imperfect Model Experiments

    E-Print Network [OSTI]

    Meng, Zhiyong

    Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II In Part I of this two-part work, the feasibility of using an ensemble Kalman filter (EnKF) for mesoscale that using an ensemble Kalman filter (EnKF) in the context of a perfect model (i.e., both the truth

  20. A MODEL FOR THE STRENGTH OF THE AS-DEPOSITED REGIONS OF LOW-ALLOY STEEL WELD METALS

    E-Print Network [OSTI]

    Cambridge, University of

    true average strain ~ true plastic strain in softer phase of a dual-phase steel ~I true plastic strain in harder phase of a dual-phase steel UTS true strain at ultimate tensile stress y true strain at yieldingCHAPTER 5 A MODEL FOR THE STRENGTH OF THE AS-DEPOSITED REGIONS OF LOW-ALLOY STEEL WELD METALS 5

  1. AN APPLICATION OF URBANSIM TO THE AUSTIN, TEXAS REGION: INTEGRATED-MODEL FORECASTS FOR THE YEAR 2030

    E-Print Network [OSTI]

    Kockelman, Kara M.

    , as well as energy consumption and greenhouse gas emissions. This work describes the modeling of year-2030 policies significantly impact the region's future land use patterns, traffic conditions, greenhouse gas (emitting over 6 billion metric tons of CO2-equivalents annually, and accounting for 22.2% of the world

  2. Regional climate model data used within the SWURVE project 2: addressing uncertainty in regional climate model data Hydrol. Earth Syst. Sci., 11(1), 10851096, 2007

    E-Print Network [OSTI]

    Boyer, Edmond

    .Ekstrom@uea.ac.uk Abstract To aid assessments of the impact of climate change on water related activities in the case study on the impacts of climate change on specific water management activities (Kilsby, 2007). Uncertainties linked, temperature, rainfall, Europe Introduction As climate model projections are often used in climate change

  3. Primordial 4He abundance: a determination based on the largest sample of HII regions with a methodology tested on model HII regions

    E-Print Network [OSTI]

    Izotov, Y I; Guseva, N G

    2013-01-01T23:59:59.000Z

    We verified the validity of the empirical method to derive the 4He abundance used in our previous papers by applying it to CLOUDY (v13.01) models. Using newly published HeI emissivities, for which we present convenient fits as well as the output CLOUDY case B hydrogen and HeI line intensities, we found that the empirical method is able to reproduce the input CLOUDY 4He abundance with an accuracy of better than 1%. The CLOUDY output data also allowed us to derive the non-recombination contribution to the intensities of the strongest Balmer hydrogen Halpha, Hbeta, Hgamma, and Hdelta emission lines and the ionisation correction factors for He. With these improvements we used our updated empirical method to derive the 4He abundances and to test corrections for several systematic effects in a sample of 1610 spectra of low-metallicity extragalactic HII regions, the largest sample used so far. From this sample we extracted a subsample of 111 HII regions with Hbeta equivalent width EW(Hbeta) > 150A, with excitation p...

  4. Aeroelastic Modeling of Offshore Turbines and Support Structures in Hurricane-Prone Regions (Poster)

    SciTech Connect (OSTI)

    Damiani, R.

    2014-03-01T23:59:59.000Z

    US offshore wind turbines (OWTs) will likely have to contend with hurricanes and the associated loading conditions. Current industry standards do not account for these design load cases (DLCs), thus a new approach is required to guarantee that the OWTs achieve an appropriate level of reliability. In this study, a sequentially coupled aero-hydro-servo-elastic modeling technique was used to address two design approaches: 1.) The ABS (American Bureau of Shipping) approach; and 2.) The Hazard Curve or API (American Petroleum Institute) approach. The former employs IEC partial load factors (PSFs) and 100-yr return-period (RP) metocean events. The latter allows setting PSFs and RP to a prescribed level of system reliability. The 500-yr RP robustness check (appearing in [2] and [3] upcoming editions) is a good indicator of the target reliability for L2 structures. CAE tools such as NREL's FAST and Bentley's' SACS (offshore analysis and design software) can be efficiently coupled to simulate system loads under hurricane DLCs. For this task, we augmented the latest FAST version (v. 8) to include tower aerodynamic drag that cannot be ignored in hurricane DLCs. In this project, a 6 MW turbine was simulated on a typical 4-legged jacket for a mid-Atlantic site. FAST-calculated tower base loads were fed to SACS at the interface level (transition piece); SACS added hydrodynamic and wind loads on the exposed substructure, and calculated mudline overturning moments, and member and joint utilization. Results show that CAE tools can be effectively used to compare design approaches for the design of OWTs in hurricane regions and to achieve a well-balanced design, where reliability levels and costs are optimized.

  5. Developing regionalized models of lithospheric thickness and velocity structure across Eurasia and the Middle East from jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities

    SciTech Connect (OSTI)

    Julia, J; Nyblade, A; Hansen, S; Rodgers, A; Matzel, E

    2009-07-06T23:59:59.000Z

    In this project, we are developing models of lithospheric structure for a wide variety of tectonic regions throughout Eurasia and the Middle East by regionalizing 1D velocity models obtained by jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities. We expect the regionalized velocity models will improve our ability to predict travel-times for local and regional phases, such as Pg, Pn, Sn and Lg, as well as travel-times for body-waves at upper mantle triplication distances in both seismic and aseismic regions of Eurasia and the Middle East. We anticipate the models will help inform and strengthen ongoing and future efforts within the NNSA labs to develop 3D velocity models for Eurasia and the Middle East, and will assist in obtaining model-based predictions where no empirical data are available and for improving locations from sparse networks using kriging. The codes needed to conduct the joint inversion of P-wave receiver functions (PRFs), S-wave receiver functions (SRFs), and dispersion velocities have already been assembled as part of ongoing research on lithospheric structure in Africa. The methodology has been tested with synthetic 'data' and case studies have been investigated with data collected at an open broadband stations in South Africa. PRFs constrain the size and S-P travel-time of seismic discontinuities in the crust and uppermost mantle, SRFs constrain the size and P-S travel-time of the lithosphere-asthenosphere boundary, and dispersion velocities constrain average S-wave velocity within frequency-dependent depth-ranges. Preliminary results show that the combination yields integrated 1D velocity models local to the recording station, where the discontinuities constrained by the receiver functions are superimposed to a background velocity model constrained by the dispersion velocities. In our first year of this project we will (i) generate 1D velocity models for open broadband seismic stations in the western half of the study area (Eurasia and the Middle East) and (ii) identify well located seismic events with event-station paths isolated to individual tectonic provinces within the study area and collect broadband waveforms and source parameters for the selected events. The 1D models obtained from the joint inversion will then be combined with published geologic terrain maps to produce regionalized models for distinctive tectonic areas within the study area, and the models will be validated through full waveform modeling of well-located seismic events recorded at local and regional distances.

  6. Impact of natural and anthropogenic aerosols on stratocumulus and precipitation in the Southeast Pacific: A regional modeling study using WRF-Chem

    SciTech Connect (OSTI)

    Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Wang, Minghuai; Ghan, Steven J.; Berg, Larry K.; Leung, Lai-Yung R.; Morrison, H.

    2012-09-28T23:59:59.000Z

    Cloud-system resolving simulations with the chemistry version of the Weather Research and Forecasting (WRF-Chem) model are used to quantify the impacts of regional anthropogenic and oceanic emissions on changes in aerosol properties, cloud macro- and microphysics, and cloud radiative forcing over the Southeast Pacific (SEP) during the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) (15 Oct–Nov 16, 2008). The effects of oceanic aerosols on cloud properties, precipitation, and the shortwave forcing counteract those of anthropogenic aerosols. Despite the relatively small changes in Na concentrations (2-12%) from regional oceanic emissions, their net effect (direct and indirect) on the surface shortwave forcing is opposite and comparable or even larger in magnitude compared to those of regional anthropogenic emissions over the SEP. Two distinct regions are identified in the VOCALS-REx domain. The near-coast polluted region is characterized with strong droplet activation suppression of small particles by sea-salt particles, the more important role of the first than the second indirect effect, low surface precipitation rate, and low aerosol-cloud interaction strength associated with anthropogenic emissions. The relatively clean remote region is characterized with large contributions of Cloud Condensation Nuclei (CCN, number concentration denoted by NCCN) and droplet number concentrations (Nd) from non-local sources (lateral boundaries), a significant amount of surface precipitation, and high aerosol-cloud interactions under a scenario of five-fold increase in anthropogenic emissions. In the clean region, cloud properties have high sensitivity (e.g., 13% increase in cloud-top height and a 9% surface albedo increase) to the moderate increase in CCN concentration (?Nccn = 13 cm-3; 25%) produced by a five-fold increase in regional anthropogenic emissions. The increased anthropogenic aerosols reduce the precipitation amount over the relatively clean remote ocean. The reduction of precipitation (as a cloud water sink) more than doubles the wet scavenging timescale, resulting in an increased aerosol lifetime in the marine boundary layer. Therefore, the aerosol impacts on precipitation are amplified by the positive feedback of precipitation on aerosol. The positive feedback ultimately alters the cloud micro- and macro-properties, leading to strong aerosol-cloud-precipitation interactions. The higher sensitivity of clouds to anthropogenic aerosols over this region is also related to a 16% entrainment rate increase due to anthropogenic aerosols. The simulated aerosol-cloud-precipitation interactions are stronger at night over the clean marine region, while during the day, solar heating results in more frequent decoupling, thinner clouds, reduced precipitation, and reduced sensitivity to anthropogenic emissions. The simulated high sensitivity to the increased anthropogenic emissions over the clean region suggests that the perturbation of the clean marine environment with anthropogenic aerosols may have a larger effect on climate than that of already polluted marine environments.

  7. Regional groundwater modeling of the saturated zone in the vicinity of Yucca Mountain, Nevada; Iterative Performance Assessment, Phase 2

    SciTech Connect (OSTI)

    Ahola, M.; Sagar, B. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1992-10-01T23:59:59.000Z

    Results of groundwater modeling of the saturated zone in the vicinity of Yucca Mountain are presented. Both a regional (200 {times} 200 km) and subregional (50 {times} 50 km) model were used in the analyses. Simulations were conducted to determine the impact of various disruptive that might take place over the life span of a proposed Yucca Mountain geologic conditions repository on the groundwater flow field, as well as changes in the water-table elevations. These conditions included increases in precipitation and groundwater recharge within the regional model, changes in permeability of existing hydrogeologic barriers, a:nd the vertical intrusion of volcanic dikes at various orientations through the saturated zone. Based on the regional analysis, the rise in the water-table under Yucca Mountain due to various postulated conditions ranged from only a few meters to 275 meters. Results of the subregional model analysis, which was used to simulate intrusive dikes approximately 4 kilometers in length in the vicinity of Yucca Mountain, showed water-table rises ranging from a few meters to as much as 103 meters. Dikes oriented approximately north-south beneath Yucca Mountain produced the highest water-table rises. The conclusions drawn from this analysis are likely to change as more site-specific data become available and as the assumptions in the model are improved.

  8. Modeling of trihalomethane (THM) formation via chlorination of the water from Dongjiang River (source water for

    E-Print Network [OSTI]

    Mazumder, Asit

    , Guangzhou, 510275, PR China c Water and Aquatic Sciences Research Program, University of Victoria, Victoria online 22 August 2007 Abstract The Dongjiang River is the major source of drinking water supply for Hong

  9. Non point source pollution modelling in the watershed managed by Integrated Conctructed Wetlands: A GIS approach. 

    E-Print Network [OSTI]

    Vyavahare, Nilesh

    2008-12-05T23:59:59.000Z

    The non-point source pollution has been recognised as main cause of eutrophication in Ireland (EPA Ireland, 2001). Integrated Constructed Wetland (ICW) is a management practice adopted in Annestown stream watershed, located in the south county...

  10. Development of a total landed cost and risk analysis model for global strategic sourcing

    E-Print Network [OSTI]

    Feller, Brian (Brian C.)

    2008-01-01T23:59:59.000Z

    Total landed cost and supply chain risk analysis are methods that many companies use to assess strategic sourcing decisions. For this project, landed cost is defined as those costs associated with material movement from a ...

  11. Modeled and observed ozone sensitivity to mobile-source emissions in Mexico City

    E-Print Network [OSTI]

    Zavala, M.

    The emission characteristics of mobile sources in the Mexico City Metropolitan Area (MCMA) have changed significantly over the past few decades in response to emission control policies, advancements in vehicle technologies ...

  12. Single-Microphone Blind Audio Source Separation via Gaussian Short+Long Term AR Models

    E-Print Network [OSTI]

    Gesbert, David

    the source separation can be performed satisfactorily, especially in clean environment, for example by using, STEricsson, Cisco, BMW Group , SAP, Monaco Telecom and Symantec. The research reported herein was also

  13. Modeling regional transportation demand in China and the impacts of a national carbon constraint

    E-Print Network [OSTI]

    Kishimoto, Paul

    2015-01-30T23:59:59.000Z

    Climate and energy policy in China will have important and uneven impacts on the country’s regionally heterogeneous transport system. In order to simulate these impacts, transport sector detail is added to a multi-sector, ...

  14. Renewable Resources: a national catalog of model projects. Volume 4. Western Solar Utilization Network Region

    SciTech Connect (OSTI)

    None

    1980-07-01T23:59:59.000Z

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Western Solar Utilization Network Region. (WHK)

  15. Renewable Resources: a national catalog of model projects. Volume 3. Southern Solar Energy Center Region

    SciTech Connect (OSTI)

    None

    1980-07-01T23:59:59.000Z

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Southern Solar Energy Center Region. (WHK)

  16. Renewable Resources: a national catalog of model projects. Volume 1. Northeast Solar Energy Center Region

    SciTech Connect (OSTI)

    None

    1980-07-01T23:59:59.000Z

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Northeast Solar Energy Center Region. (WHK).

  17. Three-dimensional modeling of ionized gas. II. Spectral energy distributions of massive and very massive stars in stationary and time-dependent modeling of the ionization of metals in HII regions

    E-Print Network [OSTI]

    Weber, J A; Hoffmann, T L

    2015-01-01T23:59:59.000Z

    HII regions play a crucial role in the measurement of the chemical composition of the interstellar medium and provide fundamental data about element abundances that constrain models of galactic chemical evolution. Discrepancies that still exist between observed emission line strengths and those predicted by nebular models can be partly attributed to the spectral energy distributions (SEDs) of the sources of ionizing radiation used in the models as well as simplifying assumptions made in nebular modeling. The influence of stellar metallicity on nebular line strength ratios, via its effect on the SEDs, is of similar importance as variations in the nebular metallicity. We have computed a grid of model atmosphere SEDs for massive and very massive O-type stars covering a range of metallicities from significantly subsolar (0.1 Zsun) to supersolar (2 Zsun). The SEDs have been computed using a state-of-the-art model atmosphere code that takes into account the attenuation of the ionizing flux by the spectral lines of ...

  18. CH4 sources estimated from atmospheric observations of CH4 and its C-13/C-12 isotopic ratios: 1. Inverse modeling of source processes

    E-Print Network [OSTI]

    Mikaloff Fletcher, S.E.; Tans, P P; Bruhwiler, L M; Miller, J B; Heimann, M

    2004-01-01T23:59:59.000Z

    Burning Coal Natural gas Landfills Total source a S0 S1 S2Burning Coal Natural gas Landfills Total source a Note that51 ] The changes in landfills, natural gas, coal, ruminant

  19. Stochastic Modeling of the Rainfall Runoff-Process for Nonpoint Source Pollutant Load Estimation

    E-Print Network [OSTI]

    Collins, Michael A.; Dickey, Roger O.

    watershed in the Lake Ray Hubbard reservoir drainage basin near Dallas, Texas. Regional rainfall characteristics were established using historical hourly data from the Federal Aviation Administration rain gage at Love Field Airport in Dallas, Texas. Hourly...

  20. Investigation of global and regional BWR instabilities with a four heated-channel Reduced Order Model

    E-Print Network [OSTI]

    Demazière, Christophe

    transport) and a heat transfer model (describing heat transfer between the fuel and the coolant). All

  1. User`s Manual for the SOURCE1 and SOURCE2 Computer Codes: Models for Evaluating Low-Level Radioactive Waste Disposal Facility Source Terms (Version 2.0)

    SciTech Connect (OSTI)

    Icenhour, A.S.; Tharp, M.L.

    1996-08-01T23:59:59.000Z

    The SOURCE1 and SOURCE2 computer codes calculate source terms (i.e. radionuclide release rates) for performance assessments of low-level radioactive waste (LLW) disposal facilities. SOURCE1 is used to simulate radionuclide releases from tumulus-type facilities. SOURCE2 is used to simulate releases from silo-, well-, well-in-silo-, and trench-type disposal facilities. The SOURCE codes (a) simulate the degradation of engineered barriers and (b) provide an estimate of the source term for LLW disposal facilities. This manual summarizes the major changes that have been effected since the codes were originally developed.

  2. Investigating the Nexus of Climate, Energy, Water, and Land at Decision-Relevant Scales: The Platform for Regional Integrated Modeling and Analysis (PRIMA)

    SciTech Connect (OSTI)

    Kraucunas, Ian P.; Clarke, Leon E.; Dirks, James A.; Hathaway, John E.; Hejazi, Mohamad I.; Hibbard, Kathleen A.; Huang, Maoyi; Jin, Chunlian; Kintner-Meyer, Michael CW; Kleese van Dam, Kerstin; Leung, Lai-Yung R.; Li, Hongyi; Moss, Richard H.; Peterson, Marty J.; Rice, Jennie S.; Scott, Michael J.; Thomson, Allison M.; Voisin, Nathalie; West, Tristram O.

    2014-02-28T23:59:59.000Z

    The Platform for Regional Integrated Modeling and Analysis (PRIMA) is an innovative modeling system developed at Pacific Northwest National Laboratory (PNNL) to simulate interactions among natural and human systems at scales relevant to regional decision making. PRIMA brings together state-of-the-art models of regional climate, hydrology, agriculture, socioeconomics, and energy systems using a flexible coupling approach. The platform can be customized to inform a variety of complex questions and decisions, such as the integrated evaluation of mitigation and adaptation options across a range of sectors. Research into stakeholder decision support needs underpins the platform's application to regional issues, including uncertainty characterization. Ongoing numerical experiments are yielding new insights into the interactions among human and natural systems on regional scales with an initial focus on the energy-land-water nexus in the upper U.S. Midwest. This paper focuses on PRIMA’s functional capabilities and describes some lessons learned to date about integrated regional modeling.

  3. Forest dynamics at regional scales: predictive models constrained with inventory data

    E-Print Network [OSTI]

    Lines, Emily

    2012-06-12T23:59:59.000Z

    by scaling from key tree-level processes, but models typically have no climate dependency. In this thesis I demonstrate how large-scale national inventories combined with improvements in computational methods mean that models that incorporate the climate...

  4. Impact of Agricultural Practice on Regional Climate in a Coupled Land Surface Mesoscale Model

    E-Print Network [OSTI]

    Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.

    2004-01-01T23:59:59.000Z

    winter wheat belt on the mesoscale environment, Monthlygeneration Penn State/NCAR mesoscale model (MM5), NCAR,in a Coupled Land Surface Mesoscale Model H.S. Cooley Energy

  5. Payback Analysis for Ground Source Heat Pump Retrofits Using eQuest Modeling Software

    E-Print Network [OSTI]

    Wahlers, Drake

    2011-12-16T23:59:59.000Z

    There has been much research and analysis done on the performance and potential energy savings related to installing a ground source heat pump (GSHP) system. Much of this research has been dedicated to the new construction industry, and focused on a...

  6. The Random Energy Model in a Magnetic Field and Joint SourceChannel Coding

    E-Print Network [OSTI]

    Merhav, Neri

    the ensemble performance (random coding exponents) of joint source­channel codes to the free energy of the REM to the free energies in the various phases of the phase diagram. While the above­described relation takes to the free energy of the REM in its different phases. The outline of this paper is as follows. In Section 2

  7. A Habitat-based Wind-Wildlife Collision Model with Application to the Upper Great Plains Region

    SciTech Connect (OSTI)

    Forcey, Greg, M.

    2012-08-28T23:59:59.000Z

    Most previous studies on collision impacts at wind facilities have taken place at the site-specific level and have only examined small-scale influences on mortality. In this study, we examine landscape-level influences using a hierarchical spatial model combined with existing datasets and life history knowledge for: Horned Lark, Red-eyed Vireo, Mallard, American Avocet, Golden Eagle, Whooping Crane, red bat, silver-haired bat, and hoary bat. These species were modeled in the central United States within Bird Conservation Regions 11, 17, 18, and 19. For the bird species, we modeled bird abundance from existing datasets as a function of habitat variables known to be preferred by each species to develop a relative abundance prediction for each species. For bats, there are no existing abundance datasets so we identified preferred habitat in the landscape for each species and assumed that greater amounts of preferred habitat would equate to greater abundance of bats. The abundance predictions for bird and bats were modeled with additional exposure factors known to influence collisions such as visibility, wind, temperature, precipitation, topography, and behavior to form a final mapped output of predicted collision risk within the study region. We reviewed published mortality studies from wind farms in our study region and collected data on reported mortality of our focal species to compare to our modeled predictions. We performed a sensitivity analysis evaluating model performance of 6 different scenarios where habitat and exposure factors were weighted differently. We compared the model performance in each scenario by evaluating observed data vs. our model predictions using spearmans rank correlations. Horned Lark collision risk was predicted to be highest in the northwestern and west-central portions of the study region with lower risk predicted elsewhere. Red-eyed Vireo collision risk was predicted to be the highest in the eastern portions of the study region and in the forested areas of the western portion; the lowest risk was predicted in the treeless portions of the northwest portion of the study area. Mallard collision risk was predicted to be highest in the eastern central portion of the prairie potholes and in Iowa which has a high density of pothole wetlands; lower risk was predicted in the more arid portions of the study area. Predicted collision risk for American Avocet was similar to Mallard and was highest in the prairie pothole region and lower elsewhere. Golden Eagle collision risk was predicted to be highest in the mountainous areas of the western portion of the study area and lowest in the eastern portion of the prairie potholes. Whooping Crane predicted collision risk was highest within the migration corridor that the birds follow through in the central portion of the study region; predicted collision risk was much lower elsewhere. Red bat collision risk was highly driven by large tracts of forest and river corridors which made up most of the areas of higher collision risk. Silver-haired bat and hoary bat predicted collision risk were nearly identical and driven largely by forest and river corridors as well as locations with warmer temperatures, and lower average wind speeds. Horned Lark collisions were mostly influenced by abundance and predictions showed a moderate correlation between observed and predicted mortality (r = 0.55). Red bat, silver-haired bat, and hoary bat predictions were much higher and shown a strong correlations with observed mortality with correlations of 0.85, 0.90, and 0.91 respectively. Red bat collisions were influenced primarily by habitat, while hoary bat and silver-haired bat collisions were influenced mainly by exposure variables. Stronger correlations between observed and predicted collision for bats than for Horned Larks can likely be attributed to stronger habitat associations and greater influences of weather on behavior for bats. Although the collision predictions cannot be compared among species, our model outputs provide a convenient and easy landscape-level tool to quick

  8. Combining remote sensing data and an inundation model to map tidal mudflat regions and improve flood predictions: A proof of concept

    E-Print Network [OSTI]

    Ezer,Tal

    Combining remote sensing data and an inundation model to map tidal mudflat regions and improve mudflats. The remote sensing-based analysis provides for the first time a way to evaluate the flood., and H. Liu (2009), Combining remote sensing data and an inundation model to map tidal mudflat regions

  9. Forward Modeling of Active Region Coronal Emissions. II. Implications for Coronal Heating This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    McTiernan, James M.

    Forward Modeling of Active Region Coronal Emissions. II. Implications for Coronal Heating of Contents and more related content is available Home Search Collections Journals About Contact us My IOPscience #12;FORWARD MODELING OF ACTIVE REGION CORONAL EMISSIONS. II. IMPLICATIONS FOR CORONAL HEATING L. L

  10. Polar-region distributions of Poynting flux: Global models compared with observations

    E-Print Network [OSTI]

    Lotko, William

    from the Preprint submitted to J. Atmospheric and Solar-Terrestrial Physics 11 July 2008 #12;DMSP F13 by the solar wind-magnetosphere interaction (Kozyra et al., 1998; Lu et al., 1998; Knipp et al., 2004; Vichare, and collisionless energization of auroral- and cusp-region plasmas, this variable energy transfer accounts

  11. Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region

    E-Print Network [OSTI]

    R. Sahu; V. K. B. Kota

    2015-03-20T23:59:59.000Z

    Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. The above model space was used in many recent shell model and interacting boson model calculations for nuclei in this region. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $1.1 \\times 10^{26}$ yr, $2.3 \\times 10^{27}$ yr and $2.2 \\times 10^{24}$ yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

  12. Comparison of Aermod and ISCST3 Models for Particulate Emissions from Ground Level Sources 

    E-Print Network [OSTI]

    Botlaguduru, Venkata Sai V.

    2010-07-14T23:59:59.000Z

    Emission factors (EFs) and results from dispersion models are key components in the air pollution regulatory process. The EPA preferred regulatory model changed from ISCST3 to AERMOD in November, 2007. Emission factors are used in conjunction...

  13. Beyond Hierarchy: Towards a Service Model supporting new Sourcing Strategies for IT

    E-Print Network [OSTI]

    -providers to realize these services. In their current releases, both the IT Infrastructure Library (ITIL modeling of services: According to ITIL, service models are blueprints for ser- vice management processes

  14. Back-calculating emission rates for ammonia and particulate matter from area sources using dispersion modeling

    E-Print Network [OSTI]

    Price, Jacqueline Elaine

    2004-11-15T23:59:59.000Z

    backward Lagrangian stochastic model and a Gaussian plume dispersion model. This analysis assessed the uncertainty surrounding each sampling procedure in order to gain a better understanding of the uncertainty in the final emission rate calculation (a basis...

  15. A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

    SciTech Connect (OSTI)

    Joan B. Blainey; Claudia C. Faunt, and Mary C. Hill

    2006-05-16T23:59:59.000Z

    This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.

  16. Supplementary materials of "High-resolution back-projection at regional distance: application to the Haiti M7.0 earthquake and comparisons with finite source studies"

    E-Print Network [OSTI]

    Ampuero, Jean Paul

    to the Haiti M7.0 earthquake and comparisons with finite source studies" L. Meng1 , J.-P. Ampuero1 , A. Sladen2 empty circles are the aftershock epicenters of the Haiti- #12;OBS campaign. The two inset maps show

  17. FOUR PI CALIBRATION AND MODELING OF A BARE GERMANIUM DETECTOR IN A CYLINDRICAL FIELD SOURCE

    SciTech Connect (OSTI)

    Dewberry, R.; Young, J.

    2011-04-29T23:59:59.000Z

    In reference 1 the authors described {gamma}-ray holdup assay of a Mossbauer spectroscopy instrument where they utilized two axial symmetric cylindrical shell acquisitions and two disk source acquisitions to determine Am-241 and Np-237 contamination. The measured contents of the two species were determined using a general detector efficiency calibration taken from a 12-inch point source.2 The authors corrected the raw spectra for container absorption as well as for geometry corrections to transform the calibration curve to the applicable axial symmetric cylindrical source - and disk source - of contamination. The authors derived the geometry corrections with exact calculus that are shown in equations (1) and (2) of our Experimental section. A cylindrical shell (oven source) acquisition configuration is described in reference 3, where the authors disclosed this configuration to gain improved sensitivity for holdup measure of U-235 in a ten-chamber oven. The oven was a piece of process equipment used in the Savannah River Plant M-Area Uranium Fuel Fabrication plant for which a U-235 holdup measurement was necessary for its decontamination and decommissioning in 2003.4 In reference 4 the authors calibrated a bare NaI detector for these U-235 holdup measurements. In references 5 and 6 the authors calibrated a bare HpGe detector in a cylindrical shell configuration for improved sensitivity measurements of U-235 in other M-Area process equipment. Sensitivity was vastly improved compared to a close field view of the sample, with detection efficiency of greater than 1% for the 185.7-keV {gamma}-ray from U-235. In none of references 3 - 7 did the authors resolve the exact calculus descriptions of the acquisition configurations. Only the empirical efficiency for detection of the 185.7-keV photon from U-235 decay was obtained. Not until the 2010 paper of reference 1 did the authors derive a good theoretical description of the flux of photons onto the front face of a detector from an axially symmetric cylindrical shell. Subsequent to publication of 1, the theoretical treatment of the cylindrical shell and disk source acquisition sources was recognized by the Los Alamos National Laboratory as suitable for including in the Safeguards Training Program.8 Therefore, we felt it was important to accurately demonstrate the calculus describing the cylindrical shell configuration for the HpGe detector and to theoretically account for the observed bare-detector efficiencies measured in references (3-6). In this paper we demonstrate the applicability of the cylindrical shell derivation to a flexible planar sheet of known Am-241, Eu-152, and Cs-137 activity that we rolled into a symmetrical cylindrical shell of radioactivity. Using the geometry correction equation of reference 1, we calculate geometry correction values using the known detector and source dimensions combined with source to detector distances. We then compare measured detection efficiencies from a cylindrical shell of activity for the 185.7-keV photon (U-235) and for the 414.3-keV photon (Pu-239) with those determined for a 12-inch point source(2,7) to demonstrate agreement between experiment and the theoretically calculated values derived by the Savannah River National Laboratory (SRNL) authors of reference 1. We demonstrate this geometry correction first for the 185.7- and 414.3-keV {gamma}-rays. But because the detector was point source calibrated at 12 inches for the energy range (60 -1700) keV (using two distinct sources) to map its intrinsic efficiency, the geometry correction for any acquisition configuration holds for all photon energies.2 We demonstrate that for ten photon energies in the range 121 keV to 967 keV. The good agreement between experiment and calculation is demonstrated at five source to detector distances using the identical shielded HpGe detector of references 4-7 as well as with a separate HpGe detector. We then extend the measurement to include a single acquisition where the flexible source is wrapped around the bare detector in a symmetrical cylinder tha

  18. air dispersion model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    source apportionment studies. In highly polluted cities such as Athens, Los Angeles and Mexico, regional scale air quality models are used to forecast air pollution episodes ...

  19. Ultracompact HII Regions

    E-Print Network [OSTI]

    Stan Kurtz; Jose Franco

    2001-11-20T23:59:59.000Z

    We review some recent observational results on the properties of ultracompact HII regions, in particular the presence of extended continuum emission surrounding ultracompact sources and the discovery of a new class of so-called ``Hypercompact'' HII regions. In addition, we discuss recent attempts to probe the density structure within UC HII regions using the technique of spectral index analysis.

  20. NEAR FIELD MODELING OF SPE1 EXPERIMENT AND PREDICTION OF THE SECOND SOURCE PHYSICS EXPERIMENTS (SPE2)

    SciTech Connect (OSTI)

    Antoun, T; Xu, H; Vorobiev, O; Lomov, I

    2011-10-20T23:59:59.000Z

    Motion along joints and fractures in the rock has been proposed as one of the sources of near-source shear wave generation, and demonstrating the validity of this hypothesis is a focal scientific objective of the source physics experimental campaign in the Climax Stock granitic outcrop. A modeling effort has been undertaken by LLNL to complement the experimental campaign, and over the long term provide a validated computation capability for the nuclear explosion monitoring community. The approach involves performing the near-field nonlinear modeling with hydrodynamic codes (e.g., GEODYN, GEODYN-L), and the far-field seismic propagation with an elastic wave propagation code (e.g., WPP). the codes will be coupled together to provide a comprehensive source-to-sensor modeling capability. The technical approach involves pre-test predictions of each of the SPE experiments using their state of the art modeling capabilities, followed by code improvements to alleviate deficiencies identified in the pre-test predictions. This spiral development cycle wherein simulations are used to guide experimental design and the data from the experiment used to improve the models is the most effective approach to enable a transition from the descriptive phenomenological models in current use to the predictive, hybrid physics models needed for a science-based modeling capability for nuclear explosion monitoring. The objective of this report is to describe initial results of non-linear motion predictions of the first two SPE shots in the Climax Stock: a 220-lb shot at a depth of 180 ft (SPE No.1), and a 2570-lb shot at a depth of 150 ft (SPE No.2). The simulations were performed using the LLNL ensemble granite model, a model developed to match velocity and displacement attenuation from HARDHAT, PILE DRIVER, and SHOAL, as well as Russian and French nuclear test data in granitic rocks. This model represents the state of the art modeling capabilities as they existed when the SPE campaign was launched in 2010, and the simulation results presented here will establish a baseline that will be used for gauging progress as planned modeling improvements are implemented during the remainder of the SPE program. The initial simulations were performed under 2D axisymmetric conditions assuming the geologic medium to be a homogeneous half space. However, logging data obtained from the emplacement hole reveal two major faults that intersect the borehole at two different depth intervals (NSTec report, 2011) and four major joint sets. To evaluate the effect of these discrete structures on the wave forms generated they have performed 2D and 3D analysis with a Lagrangian hydrocode, GEODYN-L that shares the same material models with GEODYN but can explicitly take joints and fault into consideration. They discuss results obtained using these two different approaches in this report.

  1. Simulations of Present and Future Climates in the Western United States with Four Nested Regional Climate Models

    SciTech Connect (OSTI)

    Duffy, Phil; Arritt, R.; Coquard, J.; Gutowski, William; Han, J.; Iorio, J.; Kim, Jongil; Leung, Lai R.; Roads, J.; Zeledon, E.

    2006-03-15T23:59:59.000Z

    We analyze simulations of present and future climates in the western U.S. performed with four regional climate models (RCMs) nested within two global ocean-atmosphere climate models. Our primary goal is to assess the range of regional climate responses to increased greenhouse gases in available RCM simulations. The four RCMs used different geographical domains, different increased greenhouse gas scenarios for future-climate simulations, and (in some cases) different lateral boundary conditions. For simulations of the present climate, we compare RCM results to observations and to results of the GCM that provided lateral boundary conditions to the RCM. For future-climate (increased greenhouse gas) simulations, we compare RCM results to each other and to results of the driving GCMs. When results are spatially averaged over the western U.S., we find that the results of each RCM closely follow those of the driving GCM in the same region, in both present and future climates. This is true even though the study area is in some cases a small fraction of the RCM domain. Precipitation responses predicted by the RCMs are in many regions not statistically significant compared to interannual variability. Where the predicted precipitation responses are statistically significant, they are positive. The models agree that near-surface temperatures will increase, but do not agree on the spatial pattern of this increase. The four RCMs produce very different estimates of water content of snow in the present climate, and of the change in this water content in response to increased greenhouse gases.

  2. High-resolution back-projection at regional distance: application to the Haiti1 M7.0 earthquake and comparisons with finite source studies2

    E-Print Network [OSTI]

    Ampuero, Jean Paul

    High-resolution back-projection at regional distance: application to the Haiti1 M7.0 earthquake ruptured on January 12th 2010 on a complex fault10 system near Port-au-Prince, Haiti. Offshore rupture earthquake that hit Haiti in January 2010 was one of the most devastating37 natural disasters of the last

  3. High-resolution back-projection at regional distance: application to the Haiti1 M7.0 earthquake and comparisons with finite source studies2

    E-Print Network [OSTI]

    Ampuero, Jean Paul

    High-resolution back-projection at regional distance: application to the Haiti1 M7.0 earthquake ruptured on January 12th 2010 on a complex fault10 system near Port-au-Prince, Haiti. Offshore rupture that hit Haiti in January 2010 was one of the most devastating34 natural disasters of the last decades

  4. Deformation of layered rocks in the ramp regions of thrust faults: a study with rock models

    E-Print Network [OSTI]

    Chester, Judith Savaso

    1985-01-01T23:59:59.000Z

    and thrust belts for example, thrust faults commonly occur along specific stratigraphic horizons, and folding and faulting within thrust sheets often involves slip along bedding planes (e. g. , Rich, 1934; Douglas, 1950; Dahl str om, 1970; Price, 1981...). With the regional framework of many fold and thrust belts well estab- lished, the current emphasis of many studies has turned to defining the geometries, kinematics, and deformation mechanisms of individual thrust belt structures, and the intrinsic and extrinsic...

  5. Recent Advances in Regional Climate System Modeling and Climate Change Analyses of Extreme Heat

    E-Print Network [OSTI]

    Miller, Norman L.

    2004-01-01T23:59:59.000Z

    California hydrology. J. Am. Water Resources Association 39,Land Surface and Ground Water Model for use in WatershedN.L. , 2003: California Water Resources Research, CEC Sept

  6. Review of Regional Locomotive Emission Modeling and the Constraints Posed by Activity Data

    E-Print Network [OSTI]

    Gould, Gregory; Niemeier, Debbie A.

    2009-01-01T23:59:59.000Z

    Accessed July 21, 2008. Booz Allen Hamilton Inc. LocomotiveBoard, Sacramento, 1991. Booz Allen Hamilton Inc. Report onemission model. Booz Allen Hamilton was hired to develop the

  7. Modeling the resuspension of radionuclides in Ukranian regions impacted by Chernobyl fallout

    SciTech Connect (OSTI)

    Nair, S.K.; Thiessen, K.M.; Hoffman, F.O. [SENES Oak Ridge Inc., TN (United States)] [and others

    1997-01-01T23:59:59.000Z

    Following the 1986 Chernobyl event, large amounts of radioactive materials were deposited in nearby areas. Concentrations of various radionuclides were measured in air and surface soil. To study the resuspension of radioactive particulate, three different exposure situations were developed on the basis of the collected data under the auspices of the international BIOMOVS II (BIOspheric MOdel Validation Study) project. Modelers were asked to predict seasonal air concentrations and resuspension factors at several locations at different distances from Chernobyl for six successive years following the accident. Measurements of radionuclide deposition on topsoil were provided for each site along with information on soil, vegetation, land use, surface roughness, meteorology, and climate. In this paper, the three exposure situations are described, along with the initial data set provided to the modelers; two modeling approaches used to make the endpoint predictions are also presented. After the model predictions were submitted, the measured air concentrations and resuspension factors were released to the modelers. Generally, the predictions were well within an order of magnitude of the measured values. Time-dependent trends in predictions and measurements were in good agreement with one of the models, which (a) explicitly accounted for loss processes in soil and (b) used calibration to improve its predictive capabilities. Reasons for variations between predictions and measurements, suggestions for the improvement of models, and conclusions from the model validation study are presented. 12 refs., 15 figs., 4 tabs.

  8. Cosmic Ray Confinement and Transport Models for Probing their Putative Sources

    E-Print Network [OSTI]

    Malkov, M A

    2015-01-01T23:59:59.000Z

    Recent efforts in cosmic ray (CR) confinement and transport theory are discussed. Three problems are addressed as being crucial for understanding the present day observations and their possible telltale signs of the CR origin. The first problem concerns CR behavior right after their release from a source, such as a supernova remnant (SNR). At this phase the CRs are confined near the source by self-emitted Alfven waves. The second is the problem of diffusive propagation of CRs through the turbulent ISM. This is a seemingly straightforward and long-resolved problem, but it remains controversial and reveals paradoxes. A resolution based on the Chapman-Enskog asymptotic CR transport analysis, that also includes magnetic focusing, is suggested. The third problem is about a puzzling sharp ($\\sim10^{\\circ}$) anisotropies in the CR arrival directions that might bear on important clues of their transport between the source and observer. The overarching goal is to improve our understanding of all aspects of the CR's so...

  9. Dose Reconstruction Using Computational Modeling of Handling a Particular Arsenic-73/Arsenic-74 Source

    E-Print Network [OSTI]

    Stallard, Alisha M.

    2011-08-08T23:59:59.000Z

    ). The 0.511 MeV annihilation photons from positrons were included in the 74As photon source term. 22 0.0E+00 1.0E-02 2.0E-02 3.0E-02 4.0E-02 5.0E-02 6.0E-02 7.0E-02 8.0E-02 0.0E+00 2.0E-01 4.0E-01 6.0E-01 8.0E-01 1.0E+00 1.2E+00 1.4E...V (15.4%) 1204.3 keV (2.8%) 23 The source terms used for 73As photons, 74As photons, and 74As betas are shown in Figs. 26, 27 and 28, respectively. c As-73 2.3125E+10 Bq (625 mCi) photons c Disk source 1.905 cm diam / radius...

  10. Integrated Canada-U.S. Power Sector Modeling with the Regional Energy Deployment System (ReEDS)

    SciTech Connect (OSTI)

    Martinez, A.; Eurek, K.; Mai, T.; Perry, A.

    2013-02-01T23:59:59.000Z

    The electric power system in North America is linked between the United States and Canada. Canada has historically been a net exporter of electricity to the United States. The extent to which this remains true will depend on the future evolution of power markets, technology deployment, and policies. To evaluate these and related questions, we modify the Regional Energy Deployment System (ReEDS) model to include an explicit representation of the grid-connected power system in Canada to the continental United States. ReEDS is unique among long-term capacity expansion models for its high spatial resolution and statistical treatment of the impact of variable renewable generation on capacity planning and dispatch. These unique traits are extended to new Canadian regions. We present example scenario results using the fully integrated Canada-U.S. version of ReEDS to demonstrate model capabilities. The newly developed, integrated Canada-U.S. ReEDS model can be used to analyze the dynamics of electricity transfers and other grid services between the two countries under different scenarios.

  11. Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation

    SciTech Connect (OSTI)

    Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University

    2011-01-01T23:59:59.000Z

    A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

  12. COMBINING DIVERSE DATA SOURCES FOR CEDSS, AN AGENT-BASED MODEL OF DOMESTIC ENERGY DEMAND

    E-Print Network [OSTI]

    Gotts, Nicholas Mark; Polhill, Gary; Craig, Tony; Galan-Diaz, Carlos

    2014-01-01T23:59:59.000Z

    Model CEDSS (Community Energy Demand Social Simulator) wasthe determinants of domestic energy demand and covering fivescenarios of domestic energy demand to 2050, and for its

  13. Agricultural Water Management xxx (2003) xxxxxx A GIS-based model to estimate the regionally

    E-Print Network [OSTI]

    and landscape features that affect patterns in water available to plants, soil drainage, and aeration (Jaynes. Recent advances in GIS technology fa- cilitate the seamless integration of GIS and computer-based modeling. Multiple approaches exist to integrate GIS and hydrological models (Maidment, 1993; Abel et al

  14. Use of Source Term and Air Dispersion Modeling in Planning Demolition of Highly Alpha-Contaminated Buildings

    SciTech Connect (OSTI)

    Droppo, James G.; Napier, Bruce A.; Rishel, Jeremy P.; Bloom, Richard W.

    2011-06-22T23:59:59.000Z

    The current cleanup of structures related to cold-war production of nuclear materials includes the need to demolish a number of highly alpha-contaminated structures. The process of planning for the demolition of such structures includes unique challenges related to ensuring the protection of both workers and the public. Pre-demolition modeling analyses were conducted to evaluate potential exposures resulting from the proposed demolition of a number of these structures. Estimated emission rates of transuranic materials during demolition are used as input to an air-dispersion model. The climatological frequencies of occurrence of peak air and surface exposures at locations of interest are estimated based on years of hourly meteorological records. The modeling results indicate that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. The pre-demolition modeling directed the need for better contamination characterization and/or different demolition methods—and in the end, provided a basis for proceeding with the planned demolition activities. Post-demolition modeling was also conducted for several contaminated structures, based on the actual demolition schedule and conditions. Comparisons of modeled and monitoring results are shown. Recent monitoring data from the demolition of a UO3 plant shows increments in concentrations that were previously identified in the pre-demolition modeling predictions; these comparisons confirm the validity and value of the pre-demolition source-term and air dispersion computations for planning demolition activities for other buildings with high levels of radioactive contamination.

  15. Regionalization of subsurface stormflow parameters of hydrologic models: Up-scaling from physically based numerical simulations at hillslope scale

    SciTech Connect (OSTI)

    Ali, Melkamu; Ye, Sheng; Li, Hongyi; Huang, Maoyi; Leung, Lai-Yung R.; Fiori, Aldo; Sivapalan, Murugesu

    2014-07-19T23:59:59.000Z

    Subsurface stormflow is an important component of the rainfall-runoff response, especially in steep forested regions. However; its contribution is poorly represented in current generation of land surface hydrological models (LSMs) and catchment-scale rainfall-runoff models. The lack of physical basis of common parameterizations precludes a priori estimation (i.e. without calibration), which is a major drawback for prediction in ungauged basins, or for use in global models. This paper is aimed at deriving physically based parameterizations of the storage-discharge relationship relating to subsurface flow. These parameterizations are derived through a two-step up-scaling procedure: firstly, through simulations with a physically based (Darcian) subsurface flow model for idealized three dimensional rectangular hillslopes, accounting for within-hillslope random heterogeneity of soil hydraulic properties, and secondly, through subsequent up-scaling to the catchment scale by accounting for between-hillslope and within-catchment heterogeneity of topographic features (e.g., slope). These theoretical simulation results produced parameterizations of the storage-discharge relationship in terms of soil hydraulic properties, topographic slope and their heterogeneities, which were consistent with results of previous studies. Yet, regionalization of the resulting storage-discharge relations across 50 actual catchments in eastern United States, and a comparison of the regionalized results with equivalent empirical results obtained on the basis of analysis of observed streamflow recession curves, revealed a systematic inconsistency. It was found that the difference between the theoretical and empirically derived results could be explained, to first order, by climate in the form of climatic aridity index. This suggests a possible codependence of climate, soils, vegetation and topographic properties, and suggests that subsurface flow parameterization needed for ungauged locations must account for both the physics of flow in heterogeneous landscapes, and the co-dependence of soil and topographic properties with climate, including possibly the mediating role of vegetation.

  16. A comparison of methods for calculating the matrix block source term in a double porosity model

    E-Print Network [OSTI]

    Roberts, Jean E.

    by the flow equation which is Darcy's law relating the fluid pressure with the Darcy velocity u u = -K p together with the law of conservation of mass div u = q. Here, in Darcy's equation, the effects of gravity- priate conditions, with a double porosity model. Such a model consists of a parabolic equation

  17. Final Technical Report for "Collaborative Research: Regional climate-change projections through next-generation empirical and dynamical models"

    SciTech Connect (OSTI)

    Robertson, A.W.; Ghil, M.; Kravtsov, K.; Smyth, P.J.

    2011-04-08T23:59:59.000Z

    This project was a continuation of previous work under DOE CCPP funding in which we developed a twin approach of non-homogeneous hidden Markov models (NHMMs) and coupled ocean-atmosphere (O-A) intermediate-complexity models (ICMs) to identify the potentially predictable modes of climate variability, and to investigate their impacts on the regional-scale. We have developed a family of latent-variable NHMMs to simulate historical records of daily rainfall, and used them to downscale seasonal predictions. We have also developed empirical mode reduction (EMR) models for gaining insight into the underlying dynamics in observational data and general circulation model (GCM) simulations. Using coupled O-A ICMs, we have identified a new mechanism of interdecadal climate variability, involving the midlatitude oceans mesoscale eddy field and nonlinear, persistent atmospheric response to the oceanic anomalies. A related decadal mode is also identified, associated with the oceans thermohaline circulation. The goal of the continuation was to build on these ICM results and NHMM/EMR model developments and software to strengthen two key pillars of support for the development and application of climate models for climate change projections on time scales of decades to centuries, namely: (a) dynamical and theoretical understanding of decadal-to-interdecadal oscillations and their predictability; and (b) an interface from climate models to applications, in order to inform societal adaptation strategies to climate change at the regional scale, including model calibration, correction, downscaling and, most importantly, assessment and interpretation of spread and uncertainties in multi-model ensembles. Our main results from the grant consist of extensive further development of the hidden Markov models for rainfall simulation and downscaling specifically within the non-stationary climate change context together with the development of parallelized software; application of NHMMs to downscaling of rainfall projections over India; identification and analysis of decadal climate signals in data and models; and, studies of climate variability in terms of the dynamics of atmospheric flow regimes. Each of these project components is elaborated on below, followed by a list of publications resulting from the grant.

  18. Final Technical Report for "Collaborative Research: Regional climate-change projections through next-generation empirical and dynamical models"

    SciTech Connect (OSTI)

    Kravtsov, S.; Robertson, A. W.; Ghil, M.; Smyth, P. J.

    2011-04-08T23:59:59.000Z

    This project was a continuation of previous work under DOE CCPP funding in which we developed a twin approach of non-homogeneous hidden Markov models (NHMMs) and coupled ocean-atmosphere (O-A) intermediate-complexity models (ICMs) to identify the potentially predictable modes of climate variability, and to investigate their impacts on the regional-scale. We have developed a family of latent-variable NHMMs to simulate historical records of daily rainfall, and used them to downscale seasonal predictions. We have also developed empirical mode reduction (EMR) models for gaining insight into the underlying dynamics in observational data and general circulation model (GCM) simulations. Using coupled O-A ICMs, we have identified a new mechanism of interdecadal climate variability, involving the midlatitude oceansâ?? mesoscale eddy field and nonlinear, persistent atmospheric response to the oceanic anomalies. A related decadal mode is also identified, associated with the oceansâ?? thermohaline circulation. The goal of the continuation was to build on these ICM results and NHMM/EMR model developments and software to strengthen two key pillars of support for the development and application of climate models for climate change projections on time scales of decades to centuries, namely: (a) dynamical and theoretical understanding of decadal-to-interdecadal oscillations and their predictability; and (b) an interface from climate models to applications, in order to inform societal adaptation strategies to climate change at the regional scale, including model calibration, correction, downscaling and, most importantly, assessment and interpretation of spread and uncertainties in multi-model ensembles. Our main results from the grant consist of extensive further development of the hidden Markov models for rainfall simulation and downscaling specifically within the non-stationary climate change context together with the development of parallelized software; application of NHMMs to downscaling of rainfall projections over India; identification and analysis of decadal climate signals in data and models; and, studies of climate variability in terms of the dynamics of atmospheric flow regimes. Each of these project components is elaborated on below, followed by a list of publications resulting from the grant.

  19. Predicting hurricane regional landfall rates: comparing local and basin-wide track model approaches

    E-Print Network [OSTI]

    Hall, T; Hall, Tim; Jewson, Stephen

    2006-01-01T23:59:59.000Z

    We compare two methods for making predictions of the climatological distribution of the number of hurricanes making landfall along short sections of the North American coastline. The first method uses local data, and the second method uses a basin-wide track model. Using cross-validation we show that the basin-wide track model gives better predictions for almost all parts of the coastline. This is the first time such a comparison has been made, and is the first rigourous justification for the use of basin-wide track models for predicting hurricane landfall rates and hurricane risk.

  20. NREL: Energy Analysis - Regional Energy Deployment System (ReEDS) Model

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparency Visit | NationalWebmaster To contactK-12BSM(ATB)Regional

  1. New Theoretical Model of the Complex Edge Region of Fusion Plasmas Proves

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhavenMassachusetts Regions NationalScience (SC) New ParticleAccurate

  2. Dynamical Coupled-Channel Model of Meson Production Reactions in the Nucleon Resonance Region

    SciTech Connect (OSTI)

    T.-S. H. Lee; A. Matsuyama; T. Sato

    2006-11-15T23:59:59.000Z

    A dynamical coupled-channel model is presented for investigating the nucleon resonances (N*) in the meson production reactions induced by pions and photons. Our objective is to extract the N* parameters and to investigate the meson production reaction mechanisms for mapping out the quark-gluon substructure of N* from the data. The model is based on an energy-independent Hamiltonian which is derived from a set of Lagrangians by using a unitary transformation method.

  3. A Catalog of CH_3OH 7_0-6_1 A^+ Maser Sources in Massive Star-Forming Regions. II. Masers in NGC 6334F, G8.67-0.36, and M17

    E-Print Network [OSTI]

    Gomez, Laura; Hernandez-Curiel, Idalia; Kurtz, Stan; Hofner, Peter; Araya, Esteban

    2010-01-01T23:59:59.000Z

    We present Very Large Array observations of the 7_0-6_1 A^+ methanol maser transition at 44 GHz towards NGC 6334F, G8.67-0.36, and M17. These arcsecond resolution observations complete a previous, larger VLA survey of this maser transition in high-mass star-forming regions reported by Kurtz et al. We confirm the presence of 44 GHz methanol maser emission in all three sources, detecting eight distinct maser components in NGC 6334F, twelve components in G8.67-0.36 and one in M17.

  4. Model testing using Chernobyl data: III. Atmospheric resuspension of radionuclides in Ukrainian regions impacted by Chernobyl fallout

    SciTech Connect (OSTI)

    Garger, E.K. [Inst. of Radioecology, Kiev (Ukraine); Hoffman, F.O. [SENES Oak Ridge, Inc., TN (United States); Miller, C.W. [Centers for Disease Control and Prevention, Atlanta, GA (United States)

    1996-01-01T23:59:59.000Z

    The {open_quotes}Resuspension{close_quotes} scenario is designed to test models for atmospheric resuspension of radionuclides from contaminated soils. Resuspension can be a secondary source of contamination after a release has stopped, as well as a source of contamination for people and areas not exposed to the original release. The test scenario describes three exposure situations: (1) locations within the highly contaminated 30-km zone at Chernobyl, where exposures to resuspended material are probably dominated by local processes; (2) an urban area (Kiev) outside the 30-km zone, where local processes include extensive vehicular traffic; and (3) a location 40 to 60 km west of the Chernobyl reactor, where upwind sources of contamination are important. Input data include characteristics of the {sup 137}Cs ground contamination around specific sites, climatological data for the sites, characteristics of the terrain and topography, and locations of the sampling sites. Predictions are requested for average air concentrations of {sup 137}Cs at specified locations due to resuspension of Chernobyl fallout and for specified resuspension factors and rates. Test data (field measurements) are available for all endpoints. 9 refs., 4 figs., 11 tabs.

  5. Air dispersion modeling of particulate matter from ground-level area sources 

    E-Print Network [OSTI]

    Meister, Michael Todd

    2000-01-01T23:59:59.000Z

    State Air Pollution Regulatory Agencies (SAPRAs) often use dispersion modeling to predict downwind concentrations of particulate matter (PM) from a facility. As such, a facility may be granted or denied an operating permit ...

  6. Development of source functions for modeling dissolution of residual DNAPL fingers in the saturated zone

    E-Print Network [OSTI]

    Johnson, Brian Scott

    1993-01-01T23:59:59.000Z

    and the flowing ground water. Assumming that local equilibrium conditions were acheived within the first hour hour of contact produced a poor fit of predicted to experimental values. However, an equilibrium model which assumes that equilibrium conditions...

  7. Open source software maturity model based on linear regression and Bayesian analysis

    E-Print Network [OSTI]

    Zhang, Dongmin

    2009-05-15T23:59:59.000Z

    based on Bayesian statistics. More importantly, an updating rule is established through Bayesian analysis to improve the joint distribution, and thus the objectivity of the coefficients in the linear multiple-regression model, according to new incoming...

  8. Back-calculating emission rates for ammonia and particulate matter from area sources using dispersion modeling 

    E-Print Network [OSTI]

    Price, Jacqueline Elaine

    2004-11-15T23:59:59.000Z

    Engineering directly impacts current and future regulatory policy decisions. The foundation of air pollution control and air pollution dispersion modeling lies in the math, chemistry, and physics of the environment. ...

  9. Modeling of Standing Column Wells in Ground Source Heat Pump Systems Zheng Deng O'Neill, Ph.D., P.E.

    E-Print Network [OSTI]

    Modeling of Standing Column Wells in Ground Source Heat Pump Systems Zheng Deng O'Neill, Ph.D., P Montfort University, Leicester, United Kingdom 1. INTRODUCTION In recent years, ground source heat pump-surface environment: · Ground-coupled heat pump (GCHP) systems (Closed-loop) · Surface water heat pump (SWHP) systems

  10. Assessment of Uncertainties in the Response of the African Monsoon Precipitation to Land Use change simulated by a regional model

    SciTech Connect (OSTI)

    Hagos, Samson M.; Leung, Lai-Yung R.; Xue, Yongkang; Boone, Aaron; de Sales, Fernando; Neupane, Naresh; Huang, Maoyi; Yoon, Jin-Ho

    2014-02-22T23:59:59.000Z

    Land use and land cover over Africa have changed substantially over the last sixty years and this change has been proposed to affect monsoon circulation and precipitation. This study examines the uncertainties on the effect of these changes on the African Monsoon system and Sahel precipitation using an ensemble of regional model simulations with different combinations of land surface and cumulus parameterization schemes. Although the magnitude of the response covers a broad range of values, most of the simulations show a decline in Sahel precipitation due to the expansion of pasture and croplands at the expense of trees and shrubs and an increase in surface air temperature.

  11. Modeling Complex Organic Molecules in dense regions: Eley-Rideal and complex induced reaction

    E-Print Network [OSTI]

    Ruaud, M; Hickson, K M; Gratier, P; Hersant, F; Wakelam, V

    2014-01-01T23:59:59.000Z

    Recent observations have revealed the existence of Complex Organic Molecules (COMs) in cold dense cores and prestellar cores. The presence of these molecules in such cold conditions is not well understood and remains a matter of debate since the previously proposed "warm- up" scenario cannot explain these observations. In this article, we study the effect of Eley- Rideal and complex induced reaction mechanisms of gas-phase carbon atoms with the main ice components of dust grains on the formation of COMs in cold and dense regions. Based on recent experiments we use a low value for the chemical desorption efficiency (which was previously invoked to explain the observed COM abundances). We show that our introduced mechanisms are efficient enough to produce a large amount of complex organic molecules in the gas-phase at temperatures as low as 10K.

  12. Borders as membranes :metaphors and models for improved policy in border regions.

    SciTech Connect (OSTI)

    Malczynski, Leonard A.; Passell, Howard David; Forster, Craig B. (University of Utah, Salt Lake City, UT); Cockerill, Kristan (Cockerill Consulting, Boone, NC)

    2005-10-01T23:59:59.000Z

    Political borders are controversial and contested spaces. In an attempt to better understand movement along and through political borders, this project applied the metaphor of a membrane to look at how people, ideas, and things ''move'' through a border. More specifically, the research team employed this metaphor in a system dynamics framework to construct a computer model to assess legal and illegal migration on the US-Mexico border. Employing a metaphor can be helpful, as it was in this project, to gain different perspectives on a complex system. In addition to the metaphor, the multidisciplinary team utilized an array of methods to gather data including traditional literature searches, an experts workshop, a focus group, interviews, and culling expertise from the individuals on the research team. Results from the qualitative efforts revealed strong social as well as economic drivers that motivate individuals to cross the border legally. Based on the information gathered, the team concluded that legal migration dynamics were of a scope we did not want to consider hence, available demographic models sufficiently capture migration at the local level. Results from both the quantitative and qualitative data searches were used to modify a 1977 border model to demonstrate the dynamic nature of illegal migration. Model runs reveal that current US-policies based on neo-classic economic theory have proven ineffective in curbing illegal migration, and that proposed enforcement policies are also likely to be ineffective. We suggest, based on model results, that improvement in economic conditions within Mexico may have the biggest impact on illegal migration to the U.S. The modeling also supports the views expressed in the current literature suggesting that demographic and economic changes within Mexico are likely to slow illegal migration by 2060 with no special interventions made by either government.

  13. Monte Carlo modeling and analyses of YALINA- booster subcritical assembly Part II : pulsed neutron source.

    SciTech Connect (OSTI)

    Talamo, A.; Gohar, M. Y. A.; Rabiti, C.; Nuclear Engineering Division

    2008-10-22T23:59:59.000Z

    One of the most reliable experimental methods for measuring the kinetic parameters of a subcritical assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology for characterizing the kinetic parameters of a subcritical assembly using the Sjoestrand method, which allows comparing the analytical and experimental time dependent reaction rates and the reactivity measurements. In this methodology, the reaction rate, detector response, is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the fission delayed neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction is vanished. The obtained reaction rate is superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The new calculation methodology has shown an excellent agreement with the experimental results available from the YALINA-Booster facility of Belarus. The facility has been driven by a Deuterium-Deuterium or Deuterium-Tritium pulsed neutron source and the (n,p) reaction rate has been experimentally measured by a {sup 3}He detector. The MCNP calculation has utilized the weight window and delayed neutron biasing variance reduction techniques since the detector volume is small compared to the assembly volume. Finally, this methodology was used to calculate the IAEA benchmark of the YALINA-Booster experiment.

  14. An ultra-compact virtual source FET model for deeply-scaled devices: Parameter extraction and validation for standard cell libraries and digital circuits

    E-Print Network [OSTI]

    Mysore, Omar

    In this paper, we present the first validation of the virtual source (VS) charge-based compact model for standard cell libraries and large-scale digital circuits. With only a modest number of physically meaningful parameters, ...

  15. Polar-region distributions of Poynting flux: Global models compared with observations

    E-Print Network [OSTI]

    Lotko, William

    to J. Atmospheric and Solar-Terrestrial Physics 24 May 2007 #12;empirical model. Following synopsis-latitude ionosphere and ther- mosphere is the primary sink for electromagnetic power generated by the solar wind., 2006). Including Joule heat, mechanical work on the neutral gas, and collisionless energization

  16. Resources, Conservation and Recycling 51 (2007) 847869 Modeling obsolete computer stock under regional

    E-Print Network [OSTI]

    Illinois at Chicago, University of

    2007-01-01T23:59:59.000Z

    Resources, Conservation and Recycling 51 (2007) 847­869 Modeling obsolete computer stock under and recycling systems using GIS, and demonstrate the potential economic benefits from diverting electronic buildings. © 2007 Elsevier B.V. All rights reserved. Keywords: Computer recycling; Product inventory

  17. Modeling the Dynamics of Desakota Regions: Global - Local Nexus in the Taipei Metropolitan Area

    E-Print Network [OSTI]

    Wu, Bing-Sheng

    2010-10-12T23:59:59.000Z

    Since the 1970s, Asia has experienced rapid urbanization processes, which are distinct from U.S. society, and the direction of Asian urbanization is more strongly affected by economic globalization. The desakota model, proposed by McGee and Ginsburg...

  18. The Regional Atmospheric Modeling System (RAMS): Development for Parallel Processing Computer

    E-Print Network [OSTI]

    Cirne, Walfredo

    on the mesoscale (horizontal scales from 2 km to 2000 km) for purposes ranging from operational weather forecasting and simulating convective clouds, mesoscale convective systems, cirrus clouds, and precipitating weather systems models that had a great deal of overlap, the CSU cloud/mesoscale mode (Tripoli and Cotton, 1982

  19. REGION-BASED ACTIVE SURFACE MODELLING AND ALPHA MATTING FOR UNSUPERVISED TUMOUR SEGMENTATION IN PET

    E-Print Network [OSTI]

    Wang, Jue

    hierarchical segmentation scheme consists of three steps, as shown in the system flow-chart in Fig. 2 the Poisson Gradient Vector Flow (PGVF) of Hsu et al. [2] for edge-based seg- mentation and the Markov Random segmentation model [6, 7] are used to obtain an energy function that can be minimized by convex optimization

  20. Emissions of volatile organic compounds from stationary combustion sources: Numerical modeling capabilities

    SciTech Connect (OSTI)

    Seebold, J.G. [Chevron Research and Technology Co., Richmond, CA (United States); Kee, R.J.; Lutz, A.J. [Sandia National Labs., Albuquerque, NM (United States); Pitz, W.J.; Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States); Senkan, S. [California Univ., Los Angeles, CA (United States)

    1992-09-01T23:59:59.000Z

    A collaborative research program initiated to study the emissions of a wide variety of chemical species from stationary combustion systems. These product species have been included in the Clean Air act legislation and their emissions must be rigidly controlled, but there is a need for much better understanding of the physical and chemical mechanisms that produce and consume them. We are using numerical modeling study the chemical reactions and fluid mechanical factors that occur in industrial processes: we are examining systems including premixed and diffusion flames, stirred reactors and plug flow reactors in these modeling studies to establish the major factors leading to emissions of these chemicals. In addition, we are applying advanced laser diagnostic techniques to validate the model predictions and to study the possibilities of developing sophisticated sensors to detect emissions of undesirable species in real time. This paper will discuss the organization of this collaborative effort and its results to date.

  1. MODEL-BASED SOURCE SEPARATION FOR MULTI-CLASS MOTOR IMAGERY C. Gouy-Pailler1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of Technology email: clemens.brunner@tugraz.at ABSTRACT This paper presents a general framework to recover task the best discrimi- native linear combinations of sensors. This yields different models of separation based on col- oration or time-varying energy [13]. The efficient algorithm provided by Pham [13

  2. KINETIC MODELING OF FUEL EFFECTS OVER A WIDE RANGE OF CHEMISTRY, PROPERTIES, AND SOURCES

    SciTech Connect (OSTI)

    Bunting, Bruce G [ORNL] [ORNL; Bunce, Michael [ORNL] [ORNL; Niak, Chitralkumar [Reaction Design] [Reaction Design; Puduppakkam, Karthik [Reaction Design] [Reaction Design

    2012-01-01T23:59:59.000Z

    Kinetic modeling is an important tool for engine design and can also be used for engine tuning and to study response to fuel chemistry and properties before an engine configuration is physically built and tested. Methodologies needed for studying fuel effects include development of fuel kinetic mechanisms for pure compounds, tools for designing surrogate blends of pure compounds that mimic a desired market fuel, and tools for reducing kinetic mechanisms to a size that allows inclusion in complex CFD engine models. In this paper, we demonstrate the use of these tools to reproduce engine results for a series of research diesel fuels using surrogate fuels in an engine and then modeling results with a simple 2 component surrogate blend with physical properties adjusted to vary fuel volatility. Results indicate that we were reasonably successful in mimicking engine performance of real fuels with blends of pure compounds. We were also successful in spanning the range of the experimental data using CFD and kinetic modeling, but further tuning and matching will be needed to exactly match engine performance of the real and surrogate fuels.

  3. Conceptual design of a regional water quality screening model. [RFF; Reach; HANFORD; ARQUAL; SEAS; NASQUAN

    SciTech Connect (OSTI)

    Davis, M J

    1981-01-01T23:59:59.000Z

    This water quality assessment methodology is intended to predict concentrations at future times and to estimate the impacts on water quality of energy-related activities (including industrial boilers). Estimates of impacts on water quality at future times are based on incremental changes in pollutant inputs to the body water. Important features of the model are: use of measured concentrations to account for existing conditions; consideration of incremental changes in pollutant loads; emphasis on the energy sector and industrial boilers; analysis restricted to streams only; no attempt to fully account for pollutant behavior; and flexible design, so that future improvements can be incorporated. The basic approach is very similar to the one used by Argonne's ARQUAL model but will allow more complex pollutant behavior and more flexibility in use. (PSB)

  4. Finite - difference modeling of the Yucca Mountain, Nevada Area: a study of the regional water table gradients based on hydraulic conductivity contrasts

    E-Print Network [OSTI]

    Davidson, Timothy Ross

    1994-01-01T23:59:59.000Z

    regionally corresponds with the northern limit of the Paleozoic carbonates, at the contact of the Eleana Formation, a Paleozoic aquitard. This study investigates, using finite difference modeling, the relationship between the steep hydraulic gradient...

  5. An integrated assessment modeling framework for uncertainty studies in global and regional climate change: the MIT IGSM-CAM (version 1.0)

    E-Print Network [OSTI]

    Monier, Erwan

    This paper describes a computationally efficient framework for uncertainty studies in global and regional climate change. In this framework, the Massachusetts Institute of Technology (MIT) Integrated Global System Model ...

  6. Monitoring and Modeling Non-Point Source Contributions of Host-Specific Fecal Contamination in San Pablo Bay

    E-Print Network [OSTI]

    Wuertz, Stefan; Bombardelli, Fabian A; Sirikanchana, Kwanrawee; Wang, Dan

    2009-01-01T23:59:59.000Z

    Host-Specific Fecal Contamination in San Pablo Bay Principlelivestock sources of fecal contamination in Kenya with host-Huang. Abstract Fecal contamination from non-point sources

  7. Calibration of the nonlinear ring model at the Diamond Light Source

    E-Print Network [OSTI]

    Bartolini, R; Rehm, G; Martin, I P S

    2011-01-01T23:59:59.000Z

    Nonlinear beam dynamics plays a crucial role in defining the performance of a storage ring. The beam lifetime, the injection efficiency, and the dynamic and momentum apertures available to the beam are optimized during the design phase by a proper optimization of the linear lattice and of the distribution of sextupole families. The correct implementation of the design model, especially the nonlinear part, is a nontrivial accelerator physics task. Several parameters of the nonlinear dynamics can be used to compare the real machine with the model and eventually to correct the accelerator. Most of these parameters are extracted from the analysis of turn-by-turn data after the excitation of betatron oscillations of the particles in the ring. We present the experimental results of the campaign of measurements carried out at the Diamond storage ring to characterize the nonlinear beam dynamics. A combination of frequency map analysis with the detuning with momentum measurements has allowed for a precise calibration ...

  8. Modeling the magnetic field in the protostellar source NGC 1333 IRAS 4A

    E-Print Network [OSTI]

    Jose Goncalves; Daniele Galli; Josep M. Girart

    2008-10-01T23:59:59.000Z

    Magnetic fields are believed to play a crucial role in the process of star formation. We compare high-angular resolution observations of the submillimeter polarized emission of NGC 1333 IRAS 4A, tracing the magnetic field around a low-mass protostar, with models of the collapse of magnetized molecular cloud cores. Assuming a uniform dust alignment efficiency, we computed the Stokes parameters and synthetic polarization maps from the model density and magnetic field distribution by integrations along the line-of-sight and convolution with the interferometric response. The synthetic maps are in good agreement with the data. The best-fitting models were obtained for a protostellar mass of 0.8 solar masses, of age 9e4 yr, formed in a cloud with an initial mass-to-flux ratio ~2 times the critical value. The magnetic field morphology in NGC 1333 IRAS 4A is consistent with the standard theoretical scenario for the formation of solar-type stars, where well-ordered, large-scale, rather than turbulent, magnetic fields control the evolution and collapse of the molecular cloud cores from which stars form.

  9. Evolution of HII regions in hierarchically structured molecular clouds

    E-Print Network [OSTI]

    Stanislav Shabala; Simon Ellingsen; Stan Kurtz; Larry Forbes

    2006-07-26T23:59:59.000Z

    We present observations of the H91$\\alpha$ recombination line emission towards a sample of nine HII regions associated with 6.7-GHz methanol masers, and report arcsecond-scale emission around compact cores. We derive physical parameters for our sources, and find that although simple hydrostatic models of region evolution reproduce the observed region sizes, they significantly underestimate emission measures. We argue that these findings are consistent with young source ages in our sample, and can be explained by existence of density gradients in the ionised gas.

  10. Investigation of Aerosol Indirect Effects using a Cumulus Microphysics Parameterization in a Regional Climate Model

    SciTech Connect (OSTI)

    Lim, Kyo-Sun; Fan, Jiwen; Leung, Lai-Yung R.; Ma, Po-Lun; Singh, Balwinder; Zhao, Chun; Zhang, Yang; Zhang, Guang; Song, Xiaoliang

    2014-01-29T23:59:59.000Z

    A new Zhang and McFarlane (ZM) cumulus scheme includes a two-moment cloud microphysics parameterization for convective clouds. This allows aerosol effects to be investigated more comprehensively by linking aerosols with microphysical processes in both stratiform clouds that are explicitly resolved and convective clouds that are parameterized in climate models. This new scheme is implemented in the Weather Research and Forecasting (WRF) model, which is coupled with the physics and aerosol packages from the Community Atmospheric Model version 5 (CAM5). A test case of July 2008 during the East Asian summer monsoon is selected to evaluate the performance of the new ZM scheme and to investigate aerosol effects on monsoon precipitation. The precipitation and radiative fluxes simulated by the new ZM scheme show a better agreement with observations compared to simulations with the original ZM scheme that does not include convective cloud microphysics and aerosol convective cloud interactions. Detailed analysis suggests that an increase in detrained cloud water and ice mass by the new ZM scheme is responsible for this improvement. To investigate precipitation response to increased anthropogenic aerosols, a sensitivity experiment is performed that mimics a clean environment by reducing the primary aerosols and anthropogenic emissions to 30% of that used in the control simulation of a polluted environment. The simulated surface precipitation is reduced by 9.8% from clean to polluted environment and the reduction is less significant when microphysics processes are excluded from the cumulus clouds. Ensemble experiments with ten members under each condition (i.e., clean and polluted) indicate similar response of the monsoon precipitation to increasing aerosols.

  11. First Structure Formation: I. Primordial Star Forming Regions in hierarchical models

    E-Print Network [OSTI]

    Tom Abel; Peter Anninos; Michael L. Norman; Yu Zhang

    1997-05-17T23:59:59.000Z

    We investigate the possibility of very early formation of primordial star clusters from high-\\sigma perturbations in cold dark matter dominated structure formation scenarios. For this we have developed a powerful 2-level hierarchical cosmological code with a realistic and robust treatment of multi-species primordial gas chemistry, paying special attention to the formation and destruction of hydrogen molecules, non-equilibrium ionization, and cooling processes. We performed 3-D simulations at small scales and at high redshifts and find that, analogous to simulations of large scale structure, a complex system of filaments, sheets, and spherical knots at the intersections of filaments form. On the mass scales covered by our simulations (5x10^5 - 1x10^9\\Ms) that collapse at redshifts z>25, we find that only at the spherical knots can enough H2 be formed (n_{H_2}/n_H > 5x10^-4) to cool the gas appreciably. Quantities such as the time dependence of the formation of H2 molecules, the final H2 fraction, and central densities from the simulations are compared to the theoretical predictions of Abel (1995) and Tegmark et al. (1997) and found to agree remarkably well. Comparing the 3-D results to an isobaric collapse model we further discuss the possible implications of the extensive merging of small structure that is inherent in hierarchical models. Typically only 5-8% percent of the total baryonic mass in the collapsing structures is found to cool significanlty. Assuming the Padoan (1995) model for star formation our results would predict the first stellar systems to be as small as ~30\\Ms. Some implications for primordial globular cluster formation scenarios are also discussed.

  12. Modeling Regional Air Quality Using the Near-Explicit Master Chemical Mechanism

    E-Print Network [OSTI]

    Li, Jingyi

    2014-08-01T23:59:59.000Z

    C. ................................................................................................................. 32 Figure 2-6 Pollutant rose for isopentane at C35C. Panels (a)-(c) are based on the data where the predicted wind direction and wind speed agree well with observations. Panels (d)-(f) are based on the remaining data. Units are ppb... during the entire episode. Model performance criteria and goals for particulate matter are based on the recommendations of Boylan and Russell (2006). MFB=2/N×?(Cp-Co)/(Cp+Co). Cp=predictions; Co=observations; N=number of data points. (b) Predicted...

  13. Modeling the heat transfer in geometrically complex media with a volume source

    SciTech Connect (OSTI)

    Gurevich, M. I., E-mail: gur.m@mail.ru; Tel’kovskaya, O. V.; Chukbar, B. K.; Shkarovskiy, D. A. [National Research Center Kurchatov Institute (Russian Federation)

    2014-12-15T23:59:59.000Z

    Fuel elements produced from spent fuel are porous media with spatially varying characteristics. A hierarchical discrete structure for the numerical modeling of heat-transfer processes in media with an anisotropic geometry that is characterized by both the microscopic voids and macroscopic changes in the parameters is proposed. The basic unit of the structure at its lower level is a cell that represents the local properties of the medium. The cells have a standard interface that allows one to form three-dimensional networks of such cells. Different types of cells in the network represent macroscopic changes. The potential for parallel processing is analyzed.

  14. Development of a tool dedicated to the evaluation of hydrogen term source for technological Wastes: assumptions, physical models, and validation

    SciTech Connect (OSTI)

    Lamouroux, C. [CEA Saclay, Nuclear Energy Division /DANS, Department of physico-chemistry, 91191 Gif sur yvette (France); Esnouf, S. [CEA Saclay, DSM/IRAMIS/SIS2M/Radiolysis Laboratory , 91191 Gif sur yvette (France); Cochin, F. [Areva NC,recycling BU, DIRP/RDP tour Areva, 92084 Paris La Defense (France)

    2013-07-01T23:59:59.000Z

    In radioactive waste packages hydrogen is generated, in one hand, from the radiolysis of wastes (mainly organic materials) and, in the other hand, from the radiolysis of water content in the cement matrix. In order to assess hydrogen generation 2 tools based on operational models have been developed. One is dedicated to the determination of the hydrogen source term issues from the radiolysis of the wastes: the STORAGE tool (Simulation Tool Of Emission Radiolysis Gas), the other deals with the hydrogen source term gas, produced by radiolysis of the cement matrices (the Damar tool). The approach used by the STORAGE tool for assessing the production rate of radiolysis gases is divided into five steps: 1) Specification of the data packages, in particular, inventories and radiological materials defined for a package medium; 2) Determination of radiochemical yields for the different constituents and the laws of behavior associated, this determination of radiochemical yields is made from the PRELOG database in which radiochemical yields in different irradiation conditions have been compiled; 3) Definition of hypothesis concerning the composition and the distribution of contamination inside the package to allow assessment of the power absorbed by the constituents; 4) Sum-up of all the contributions; And finally, 5) validation calculations by comparison with a reduced sampling of packages. Comparisons with measured values confirm the conservative character of the methodology and give confidence in the safety margins for safety analysis report.

  15. Conceptual design of first toroidal electron cyclotron resonance ion source and modeling of ion extraction from it

    E-Print Network [OSTI]

    Caliri, C; Volpe, F A

    2015-01-01T23:59:59.000Z

    Electron Cyclotron Resonance Ion Sources (ECRIS) progressed to higher and higher ion currents and charge states by adopting stronger magnetic fields (beneficial for confinement) and proportionally higher ECR frequencies. Further improvements would require the attainment of "triple products" of density, temperature and confinement time comparable with major fusion experiments. For this, we propose a new, toroidal rather than linear, ECRIS geometry, which would at the same time improve confinement and make better use of the magnetic field. Ion extraction is more complicated than from a linear device, but feasible, as our modelling suggests: single-particle tracings showed successful extraction by at least two techniques, making use respectively of a magnetic extractor and of ExB drifts. Additional techniques are briefly discussed.

  16. Dynamical Coupled-Channel Model of pi-N scattering in te W < 2 GeV Nucleon Resonane Region

    SciTech Connect (OSTI)

    T.S.H. Lee; B. Julia-diaz; A. Matsuyama; T. Sato

    2007-12-01T23:59:59.000Z

    As a first step to analyze the electromagnetic meson production reactions in the nucleon resonance region, the parameters of the hadronic interactions of a dynamical coupled-channel model, developed in {\\it Physics Reports 439, 193 (2007)}, are determined by fitting the empirical $\\pi N$ elastic scattering amplitudes of SAID up to 2 GeV. The channels included in the calculations are $\\pi N$, $\\eta N$ and $\\pi\\pi N$ which has $\\pi\\Delta$, $\\rho N$, and $\\sigma N$ resonant components. The non-resonant meson-baryon interactions of the model are derived from a set of Lagrangians by using a unitary transformation method. One or two bare excited nucleon states in each of $S$, $P$, $D$, and $F$ partial waves are included to generate the resonant amplitudes in the fits. The predicted total cross sections of $\\pi N$ reactions and $\\pi N\\rightarrow \\eta N$ reactions are in good agreement with the data. Applications of the constructed model in analyzing the electromagnetic meson production data as well as the future developments are discussed.

  17. Gaseous Chemistry and Aerosol Mechanism Developments for Version 3.5.1 of the Online Regional Model, WRF-Chem

    SciTech Connect (OSTI)

    Archer-Nicholls, Scott; Lowe, Douglas; Utembe, Steve; Allan, James D.; Zaveri, Rahul A.; Fast, Jerome D.; Hodnebrog, Oivind; Denier van der Gon, Hugo; McFiggans, Gordon

    2014-11-08T23:59:59.000Z

    We have made a number of developments in the regional coupled model WRF-Chem, with the aim of making the model more suitable for prediction of atmospheric composition and of interactions between air quality and weather. We have worked on the European domain, with a particular focus on making the model suitable for the study of night time chemistry and oxidation by the nitrate radical in the UK atmosphere. A reduced form of the Common Reactive Intermediates gas-phase chemical mechanism (CRIv2-R5) has been implemented to enable more explicit simulation of VOC degradation. N2O5 heterogeneous chemistry has been added to the existing sectional MOSAIC aerosol module, and coupled to both the CRIv2-R5 and existing CBM-Z gas phase scheme. Modifications have also been made to the sea-spray aerosol emission representation, allowing the inclusion of primary organic material in sea-spray aerosol. Driven by appropriate emissions, wind fields and chemical boundary conditions, implementation of the different developments is illustrated in order to demonstrate the impact that these changes have in the North-West European domain. These developments are now part of the freely available WRF-Chem distribution.

  18. Proposal to Acquire Experimental Data and to Model the Results with a Monte Carlo Calculation of a Secondary Source Correction Factor for Area Source Acquisitions of Holdup y-PHA Measurements

    SciTech Connect (OSTI)

    Dewberry, R.

    2003-02-10T23:59:59.000Z

    This report describes an interference observed when acquiring y-ray holdup data. The interference comes from secondary contaminated surfaces that contribute to the y-ray signal when acquiring data in the area source configuration. It is often the case that these unwanted contributions can not be isolated and eliminated, so it is necessary to mathematically correct for the contribution. In this report we propose experiments to acquire the necessary data to determine the experimental correction factor specifically for highly enriched uranium holdup measurements. We then propose to use the MCNP Monte Carlo computer code to model the contribution in several acquisition configurations and for multiple interfering y-ray energies. Results will provide a model for calculation of this secondary source correction factor for future holdup measurements. We believe the results of the experiments and modeling of the data acquired in this proposal will have a significant impact on deactivation and de commissioning activities throughout the DOE weapons complex.

  19. Moisture Flux Convergence in Regional and Global Climate Models: Implications for Droughts in the Southwestern United States Under Climate Change

    SciTech Connect (OSTI)

    Gao, Yanhong; Leung, Lai-Yung R.; Salathe, E.; Dominguez, Francina; Nijssen, Bart; Lettenmaier, D. P.

    2012-05-10T23:59:59.000Z

    The water cycle of the southwestern United States (SW) is dominated by winter storms that maintain a positive annual net precipitation. Analysis of the control and future climate from four pairs of regional and global climate models (RCMs and GCMs) shows that the RCMs simulate a higher fraction of transient eddy moisture fluxes because the hydrodynamic instabilities associated with flow over complex terrain are better resolved. Under global warming, this enables the RCMs to capture the response of transient eddies to increased atmospheric stability that allows more moisture to converge on the windward side of the mountains by blocking. As a result, RCMs simulate enhanced transient eddy moisture convergence in the SW compared to GCMs, although both robustly simulate drying due to enhanced moisture divergence by the divergent mean flow in a warmer climate. This enhanced convergence leads to reduced susceptibility to hydrological change in the RCMs compared to GCMs.

  20. The prediction of radiation-induced liver dysfunction using a local dose and regional venous perfusion model

    SciTech Connect (OSTI)

    Cao Yue; Platt, Joel F.; Francis, Isaac R; Balter, James M.; Pan, Charlie; Normolle, Daniel; Ben-Josef, Edgar; Haken, Randall K. ten; Lawrence, Theodore S. [Departments of Radiation Oncology and Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States)

    2007-02-15T23:59:59.000Z

    We have shown that high dose conformal radiation combined with chemotherapy appears to prolong the survival of patients with unresectable intrahepatic cancers. The ability to safely deliver higher doses is primarily limited by the development of radiation-induced liver disease, characterized by venous occlusion. In this study, we investigated whether portal venous perfusion measured prior to the end of radiation therapy (RT) together with dose could predict liver venous perfusion dysfunction after treatment. Ten patients with unresectable intrahepatic cancer participated in an IRB-approved computer tomography (CT) perfusion study. Hepatic arterial and portal vein perfusion distributions were estimated by using dynamic contrast enhanced CT and the single compartmental model. Scans were obtained at four time points: prior to treatment, after 15 and 30 fractions of 1.5 Gy treatments, and one month following the completion of RT. Multivariant linear regression was used to determine covariances among the first three time point measurements plus dose for prediction of the post RT measurement. The reduction in the regional venous perfusion one month following RT was predicted by the local accumulated dose and the change in the regional venous perfusion after {approx}30 fractions (F=90.6,p<0.000 01). Each Gy produced an approximately 1.2% of reduction in the venous perfusion. This local dose and venous perfusion model has the potential to predict individual sensitivity to radiation. This is the first step toward developing a method to deliver higher and potentially more curative radiation doses to the patients who can safely receive these higher doses.

  1. Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic using a High-Resolution Regional Arctic Climate System Model

    SciTech Connect (OSTI)

    Lettenmaier, Dennis P

    2013-04-08T23:59:59.000Z

    Primary activities are reported in these areas: climate system component studies via one-way coupling experiments; development of the Regional Arctic Climate System Model (RACM); and physical feedback studies focusing on changes in Arctic sea ice using the fully coupled model.

  2. Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region

    E-Print Network [OSTI]

    R. Sahu; V. K. B. Kota

    2014-09-17T23:59:59.000Z

    Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $9.6 \\times 10^{25}$yr, $1.9 \\times 10^{27}$yr and $1.95 \\times 10^{24}$yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

  3. Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region

    E-Print Network [OSTI]

    Sahu, R

    2014-01-01T23:59:59.000Z

    Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $9.6 \\times 10^{25}$yr, $1.9 \\times 10^{27}$yr and $1.95 \\times 10^{24}$yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

  4. Radiation source

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01T23:59:59.000Z

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the relativistic electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region of the high-density plasma target.

  5. Force-free field modeling of twist and braiding-induced magnetic energy in an active-region corona

    SciTech Connect (OSTI)

    Thalmann, J. K. [Institute of Physics/IGAM, University of Graz, Universitätsplatz 5, A-8010 Graz (Austria); Tiwari, S. K.; Wiegelmann, T., E-mail: julia.thalmann@uni-graz.at [Max Plank Institute for Solar System Research, Max-Planck-Str. 2, D-37191 Katlenburg-Lindau (Germany)

    2014-01-01T23:59:59.000Z

    The theoretical concept that braided magnetic field lines in the solar corona may dissipate a sufficient amount of energy to account for the brightening observed in the active-region (AR) corona has only recently been substantiated by high-resolution observations. From the analysis of coronal images obtained with the High Resolution Coronal Imager, first observational evidence of the braiding of magnetic field lines was reported by Cirtain et al. (hereafter CG13). We present nonlinear force-free reconstructions of the associated coronal magnetic field based on Solar Dynamics Observatory/Helioseismic and Magnetic Imager vector magnetograms. We deliver estimates of the free magnetic energy associated with a braided coronal structure. Our model results suggest (?100 times) more free energy at the braiding site than analytically estimated by CG13, strengthening the possibility of the AR corona being heated by field line braiding. We were able to appropriately assess the coronal free energy by using vector field measurements and we attribute the lower energy estimate of CG13 to the underestimated (by a factor of 10) azimuthal field strength. We also quantify the increase in the overall twist of a flare-related flux rope that was noted by CG13. From our models we find that the overall twist of the flux rope increased by about half a turn within 12 minutes. Unlike another method to which we compare our results, we evaluate the winding of the flux rope's constituent field lines around each other purely based on their modeled coronal three-dimensional field line geometry. To our knowledge, this is done for the first time here.

  6. Effect of Terrestrial and Marine Organic Aerosol on Regional and Global Climate: Model Development, Application, and Verification with Satellite Data

    SciTech Connect (OSTI)

    Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

    2012-03-28T23:59:59.000Z

    In this DOE project the improvements to parameterization of marine primary organic matter (POM) emissions, hygroscopic properties of marine POM, marine isoprene derived secondary organic aerosol (SOA) emissions, surfactant effects, new cloud droplet activation parameterization have been implemented into Community Atmosphere Model (CAM 5.0), with a seven mode aerosol module from the Pacific Northwest National Laboratory (PNNL)���¢��������s Modal Aerosol Model (MAM7). The effects of marine aerosols derived from sea spray and ocean emitted biogenic volatile organic compounds (BVOCs) on microphysical properties of clouds were explored by conducting 10 year CAM5.0-MAM7 model simulations at a grid resolution 1.9�������°��������2.5�������° with 30 vertical layers. Model-predicted relationship between ocean physical and biological systems and the abundance of CCN in remote marine atmosphere was compared to data from the A-Train satellites (MODIS, CALIPSO, AMSR-E). Model simulations show that on average, primary and secondary organic aerosol emissions from the ocean can yield up to 20% increase in Cloud Condensation Nuclei (CCN) at 0.2% Supersaturation, and up to 5% increases in droplet number concentration of global maritime shallow clouds. Marine organics were treated as internally or externally mixed with sea salt. Changes associated with cloud properties reduced (absolute value) the model-predicted short wave cloud forcing from -1.35 Wm-2 to -0.25 Wm-2. By using different emission scenarios, and droplet activation parameterizations, this study suggests that addition of marine primary aerosols and biologically generated reactive gases makes an important difference in radiative forcing assessments. All baseline and sensitivity simulations for 2001 and 2050 using global-through-urban WRF/Chem (GU-WRF) were completed. The main objective of these simulations was to evaluate the capability of GU-WRF for an accurate representation of the global atmosphere by exploring the most accurate configuration of physics options in GWRF for global scale modeling in 2001 at a horizontal grid resolution of 1�������° x 1�������°. GU-WRF model output was evaluated using observational datasets from a variety of sources including surface based observations (NCDC and BSRN), model reanalysis (NCEP/ NCAR Reanalysis and CMAP), and remotely-sensed data (TRMM) to evaluate the ability of GU-WRF to simulate atmospheric variables at the surface as well as aloft. Explicit treatment of nanoparticles produced from new particle formation in GU-WRF/Chem-MADRID was achieved by expanding particle size sections from 8 to 12 to cover particles with the size range of 1.16 nm to 11.6 �������µm. Simulations with two different nucleation parameterizations were conducted for August 2002 over a global domain at a 4�������º by 5�������º horizontal resolution. The results are evaluated against field measurement data from the 2002 Aerosol Nucleation and Real Time Characterization Experiment (ANARChE) in Atlanta, Georgia, as well as satellite and reanalysis data. We have also explored the relationship between ���¢��������clean marine���¢������� aerosol optical properties and ocean surface wind speed using remotely sensed data from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board the CALIPSO satellite and the Advanced Microwave Scanning Radiometer (AMSR-E) on board the AQUA satellite. Detailed data analyses

  7. Quasar H II Regions During Cosmic Reionization

    E-Print Network [OSTI]

    Marcelo A. Alvarez; Tom Abel

    2007-09-10T23:59:59.000Z

    Cosmic reionization progresses as HII regions form around sources of ionizing radiation. Their average size grows continuously until they percolate and complete reionization. We demonstrate how this typical growth can be calculated around the largest, biased sources of UV emission, such as quasars, by further developing an analytical model based on the excursion set formalism. This approach allows us to calculate the sizes and growth of the HII regions created by the progenitors of any dark matter halo of given mass and redshift with a minimum of free parameters. Statistical variations in the size of these pre-existing HII regions are an additional source of uncertainty in the determination of very high redshift quasar properties from their observed HII region sizes. We use this model to demonstrate that the transmission gaps seen in very high redshift quasars can be understood from the radiation of only their progenitors and associated clustered small galaxies. The fit sets a lower limit on the redshift of overlap at z = 5.8 +/- 0.1. This interpretation makes the transmission gaps independent of the age of the quasars observed. If this interpretation were correct it would raise the prospects of using radio interferometers currently under construction to detect the epoch of reionization.

  8. Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic Using a High-Resolution Regional Arctic Climate Model

    SciTech Connect (OSTI)

    Cassano, John [Principal Investigator

    2013-06-30T23:59:59.000Z

    The primary research task completed for this project was the development of the Regional Arctic Climate Model (RACM). This involved coupling existing atmosphere, ocean, sea ice, and land models using the National Center for Atmospheric Research (NCAR) Community Climate System Model (CCSM) coupler (CPL7). RACM is based on the Weather Research and Forecasting (WRF) atmospheric model, the Parallel Ocean Program (POP) ocean model, the CICE sea ice model, and the Variable Infiltration Capacity (VIC) land model. A secondary research task for this project was testing and evaluation of WRF for climate-scale simulations on the large pan-Arctic model domain used in RACM. This involved identification of a preferred set of model physical parameterizations for use in our coupled RACM simulations and documenting any atmospheric biases present in RACM.

  9. A three-dimensional numerical model of predevelopment conditions in the Death Valley regional ground-water flow system, Nevada and California

    SciTech Connect (OSTI)

    D'Agnese, F.A.; O'Brien, G.M.; Faunt, C.C.; Belcher, W.R.; San Juan, Carma

    2002-11-22T23:59:59.000Z

    In the early 1990's, two numerical models of the Death Valley regional ground-water flow system were developed by the U.S. Department of Energy. In general, the two models were based on the same basic hydrogeologic data set. In 1998, the U.S. Department of Energy requested that the U.S. Geological Survey develop and maintain a ground-water flow model of the Death Valley region in support of U.S. Department of Energy programs at the Nevada Test Site. The purpose of developing this ''second-generation'' regional model was to enhance the knowledge and understanding of the ground-water flow system as new information and tools are developed. The U.S. Geological Survey also was encouraged by the U.S. Department of Energy to cooperate to the fullest extent with other Federal, State, and local entities in the region to take advantage of the benefits of their knowledge and expertise. The short-term objective of the Death Valley regional ground-water flow system project was to develop a steady-stat e representation of the predevelopment conditions of the ground-water flow system utilizing the two geologic interpretations used to develop the previous numerical models. The long-term objective of this project was to construct and calibrate a transient model that simulates the ground-water conditions of the study area over the historical record that utilizes a newly interpreted hydrogeologic conceptual model. This report describes the result of the predevelopment steady-state model construction and calibration.

  10. Numerical Simulation of Inter-basin Groundwater Flow into Northern Yucca Flat, Nevada National Security Site, Using the Death Valley Regional Flow System Model

    SciTech Connect (OSTI)

    Pohlmann Karl,Ye Ming

    2012-03-01T23:59:59.000Z

    Models of groundwater flow for the Yucca Flat area of the Nevada National Security Site (NNSS) are under development by the U.S. Department of Energy (DOE) for corrective action investigations of the Yucca Flat-Climax Mine Corrective Action Unit (CAU). One important aspect of these models is the quantity of inter-basin groundwater flow from regional systems to the north. This component of flow, together with its uncertainty, must be properly accounted for in the CAU flow models to provide a defensible regional framework for calculations of radionuclide transport that will support determinations of the Yucca Flat-Climax Mine contaminant boundary. Because characterizing flow boundary conditions in northern Yucca Flat requires evaluation to a higher level of detail than the scale of the Yucca Flat-Climax Mine CAU model can efficiently provide, a study more focused on this aspect of the model was required.

  11. Meticulously Detailed Eye Region Model and Its Application to Analysis... file:///D:/EndNotesData/Emotion-Converted.Data/PDF/TPAMI%20Publ... 1 of 17 2/24/2008 9:30 PM

    E-Print Network [OSTI]

    Cohn, Jeffrey F.

    Meticulously Detailed Eye Region Model and Its Application to Analysis... file-8828/06/$20.00 © 2006 IEEE Published by the IEEE Computer Society Meticulously Detailed Eye Region Model and Its of detailed analysis of eye region images in terms of the position of the iris, degree of eyelid opening

  12. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    SciTech Connect (OSTI)

    Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

    2013-08-01T23:59:59.000Z

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose–response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=?0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage.

  13. Spatial Analysis of Emissions Sources for HCCI Combustion at Low Loads Using a Multi-Zone Model

    SciTech Connect (OSTI)

    Aceves, S M; Flowers, D L; Espinosa-Loza, F; Martinez-Frias, J; Dec, J E; Sjoberg, M; Dibble, R W; Hessel, R P

    2004-02-20T23:59:59.000Z

    We have conducted a detailed numerical analysis of HCCI engine operation at low loads to investigate the sources of HC and CO emissions and the associated combustion inefficiencies. Engine performance and emissions are evaluated as fueling is reduced from typical HCCI conditions, with an equivalence ratio f = 0.26 to very low loads (f = 0.04). Calculations are conducted using a segregated multi-zone methodology and a detailed chemical kinetic mechanism for iso-octane with 859 chemical species. The computational results agree very well with recent experimental results. Pressure traces, heat release rates, burn duration, combustion efficiency and emissions of hydrocarbon, oxygenated hydrocarbon, and carbon monoxide are generally well predicted for the whole range of equivalence ratios. The computational model also shows where the pollutants originate within the combustion chamber, thereby explaining the changes in the HC and CO emissions as a function of equivalence ratio. The results of this paper contribute to the understanding of the high emission behavior of HCCI engines at low equivalence ratios and are important for characterizing this previously little explored, yet important range of operation.

  14. Ecosystem-scale Selenium Model for the San Francisco Bay-Delta Regional Ecosystem Restoration Implementation Plan

    E-Print Network [OSTI]

    Presser, Theresa S.; Luoma, Samuel N.

    2013-01-01T23:59:59.000Z

    both agricultural and oil refinery sources of Se (SFBRWQCBSe • hydrodynamics • oil refinery effluent • North Bay •1) internal inputs of oil refinery wastewaters from pro-

  15. A simple object-oriented and open source model for scientific and policy analyses of the global climate system–Hector v1.0

    SciTech Connect (OSTI)

    Hartin, Corinne A.; Patel, Pralit L.; Schwarber, Adria; Link, Robert P.; Bond-Lamberty, Benjamin

    2015-01-01T23:59:59.000Z

    Simple climate models play an integral role in policy and scientific communities. They are used for climate mitigation scenarios within integrated assessment models, complex climate model emulation, and uncertainty analyses. Here we describe Hector, an open source, object-oriented, simple global climate carbon-cycle model. This model runs essentially instantaneously while still representing the most critical global scale earth system processes. Hector has three main carbon pools: an atmosphere, land, and ocean. The model’s terrestrial carbon cycle includes respiration and primary production, accommodating arbitrary geographic divisions into, e.g., ecological biomes or political units. Hector’s actively solves the inorganic carbon system in the surface ocean, directly calculating air-sea fluxes of carbon and ocean pH. Hector reproduces the global historical trends of atmospheric [CO2] and surface temperatures. The model simulates all four Representative Concentration Pathways with high correlations (R >0.7) with current observations, MAGICC (a well-known simple climate model), and the Coupled Model Intercomparison Project version 5. Hector is freely available under an open source license, and its modular design will facilitate a broad range of research in various areas.

  16. Extended emission associated with young HII regions

    E-Print Network [OSTI]

    S. P. Ellingsen; S. S. Shabala; S. E. Kurtz

    2004-12-06T23:59:59.000Z

    We have used the Australia Telescope Compact Array (ATCA) to make observations of a sample of eight young ultra-compact HII regions, selected on the basis that they have associated class II methanol maser emission. We have made observations sensitive to both compact and extended structures and find both to be present in most sources. The scale of the extended emission in our sample is in general less than that observed towards samples based on IRAS properties, or large single-dish flux densities. Our observations are consistent with a scenario where extended and compact radio continuum emission coexists within HII regions for a significant period of time. We suggest that these observations are consistent with a model where HII evolution takes place within hierarchically structured molecular clouds. This model is the subject of a companion paper (Shabala et al. 2005) and addresses both the association between compact and extended emission and UCHII region lifetime problem.

  17. Impacts of Large-scale Surface Modifications on Meteorological Conditions and Energy Use: A 10-Region Modeling Study

    E-Print Network [OSTI]

    Taha, H.

    2011-01-01T23:59:59.000Z

    104. Pielke, R, 1984: Mesoscale Meteorological Modeling . •the CSUMM, as any other mesoscale model, is typically runApplications International Mesoscale Model. SYSAPP- 921069,

  18. Downscaling Global Land Cover Projections from an Integrated Assessment Model for Use in Regional Analyses: Results and Evaluation for the US from 2005 to 2095

    SciTech Connect (OSTI)

    West, Tristram O.; Le Page, Yannick LB; Huang, Maoyi; Wolf, Julie; Thomson, Allison M.

    2014-06-05T23:59:59.000Z

    Projections of land cover change generated from Integrated Assessment Models (IAM) and other economic-based models can be applied for analyses of environmental impacts at subregional and landscape scales. For those IAM and economic models that project land use at the sub-continental or regional scale, these projections must be downscaled and spatially distributed prior to use in climate or ecosystem models. Downscaling efforts to date have been conducted at the national extent with relatively high spatial resolution (30m) and at the global extent with relatively coarse spatial resolution (0.5 degree).

  19. Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01T23:59:59.000Z

    ice sheet model with a mesoscale climate model By Nicole-ice sheet model with a mesoscale climate model Copyrightice sheet model with a mesoscale climate model by Nicole-

  20. The rapidly evolving field of decadal climate prediction, using initialized climate models to produce time-evolving predictions of regional climate, is producing new results for

    E-Print Network [OSTI]

    , and it is on those time scales of interest to water managers that decadal climate prediction is being appliedThe rapidly evolving field of decadal climate prediction, using initialized climate models to produce time-evolving predictions of regional climate, is producing new results for predictions

  1. 2D versus 1D ground-motion modelling for the Friuli region, north-eastern Italy1 W. Imperatori1, *

    E-Print Network [OSTI]

    Boyer, Edmond

    2D versus 1D ground-motion modelling for the Friuli region, north-eastern Italy1 2 W. Imperatori1 and CO2 Storage Security Division, BRGM, 3 avenue C. Guillemin, 450607 Orléans Cedex 2, France.8 9 affects ground motions, particularly in terms of peak ground velocity (PGV). The decay of PGV14

  2. QUANTIFICATION OF GLACIER CHANGES USING ICESAT ELEVATION DATA AND THE SRTM DIGITAL ELEVATION MODEL IN THE WESTERN KARAKORAM HIMALAYA REGION Bibi S. Naz1

    E-Print Network [OSTI]

    Cherkauer, Keith

    QUANTIFICATION OF GLACIER CHANGES USING ICESAT ELEVATION DATA AND THE SRTM DIGITAL ELEVATION MODEL, 47907. Although notable rates of glacier retreat have been monitored across the Eastern Himalaya region in recent years, glacier changes in the Western Karakoram Himalaya are not well documented. Snowmelt from

  3. Simulating the connections of ENSO and the rainfall regime of East Africa and the upper Blue Nile region using a climate model of the Tropics

    E-Print Network [OSTI]

    Zaroug, M. A. H.

    We simulate the observed statistical relationship between ENSO and the rainfall regime of the upper Blue Nile using the tropical-band version of the regional climate model RegCM4 (or Reg-TB). An ensemble of nine simulations ...

  4. Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part I: Perfect Model Experiments

    E-Print Network [OSTI]

    Meng, Zhiyong

    Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part I the potential of using the ensemble Kalman filter (EnKF) for mesoscale and regional-scale data assimilation are assimilated. 1. Introduction The ensemble-based data assimilation method [en- semble Kalman filter (En

  5. Modeling the Summertime Climate of Southwest Asia: The Role of Land Surface Processes in Shaping the Climate of Semiarid Regions

    E-Print Network [OSTI]

    Marcella, Marc P.

    Presented is a study on the role of land surface processes in determining the summertime climate over the semiarid region of southwest Asia. In this region, a warm surface air temperature bias of 3.5°C is simulated in the ...

  6. Computer programs for developing source terms for a UF{sub 6} dispersion model to simulate postulated UF{sub 6} releases from buildings

    SciTech Connect (OSTI)

    Williams, W.R.

    1985-03-01T23:59:59.000Z

    Calculational methods and computer programs for the analysis of source terms for postulated releases of UF{sub 6} are presented. Required thermophysical properties of UF{sub 6}, HF, and H{sub 2}O are described in detail. UF{sub 6} reacts with moisture in the ambient environment to form HF and H{sub 2}O. The coexistence of HF and H{sub 2}O significantly alters their pure component properties, and HF vapor polymerizes. Transient compartment models for simulating UF{sub 6} releases inside gaseous diffusion plant feed and withdrawl buildings and cascade buildings are also described. The basic compartment model mass and energy balances are supported by simple heat transfer, ventilation system, and deposition models. A model that can simulate either a closed compartment or a steady-state ventilation system is also discussed. The transient compartment models provide input to an atmospheric dispersion model as output.

  7. Nitrous oxide (N?O) isotopic composition in the troposphere : instrumentation, observations at Mace Head, Ireland, and regional modeling

    E-Print Network [OSTI]

    Potter, Katherine Ellison

    2011-01-01T23:59:59.000Z

    Nitrous oxide (N?O) is a significant greenhouse gas and main contributor to stratospheric ozone destruction. Surface measurements of N?O mole fractions have been used to attribute source and sink strengths, but large ...

  8. Surface energy partitioning over four dominant vegetation types across the United States in a coupled regional climate model

    E-Print Network [OSTI]

    Kueppers, Lara M.

    Slopes Model (PRISM) data) and to standard WRF model output. We found that WRF3-CLM3.5 can capture and Forecasting Model 3­Community Land Model 3.5 (WRF3-CLM3.5), by comparing model output to observations (Ameri simulation of downward solar radiation could reduce the energy flux and temperature biases. After adding

  9. Renewable Resources: a national catalog of model projects. Volume 2. Mid-American Solar Energy Complex Region

    SciTech Connect (OSTI)

    None

    1980-07-01T23:59:59.000Z

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Mid-American Solar Energy Complex Region. (WHK)

  10. Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model

    SciTech Connect (OSTI)

    Brian A. Ebel; John R. Nimmo

    2009-09-11T23:59:59.000Z

    Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of these end members.

  11. Quantum key distribution with entangled photon sources

    E-Print Network [OSTI]

    Xiongfeng Ma; Chi-Hang Fred Fung; Hoi-Kwong Lo

    2007-03-14T23:59:59.000Z

    A parametric down-conversion (PDC) source can be used as either a triggered single photon source or an entangled photon source in quantum key distribution (QKD). The triggering PDC QKD has already been studied in the literature. On the other hand, a model and a post-processing protocol for the entanglement PDC QKD are still missing. In this paper, we fill in this important gap by proposing such a model and a post-processing protocol for the entanglement PDC QKD. Although the PDC model is proposed to study the entanglement-based QKD, we emphasize that our generic model may also be useful for other non-QKD experiments involving a PDC source. Since an entangled PDC source is a basis independent source, we apply Koashi-Preskill's security analysis to the entanglement PDC QKD. We also investigate the entanglement PDC QKD with two-way classical communications. We find that the recurrence scheme increases the key rate and Gottesman-Lo protocol helps tolerate higher channel losses. By simulating a recent 144km open-air PDC experiment, we compare three implementations -- entanglement PDC QKD, triggering PDC QKD and coherent state QKD. The simulation result suggests that the entanglement PDC QKD can tolerate higher channel losses than the coherent state QKD. The coherent state QKD with decoy states is able to achieve highest key rate in the low and medium-loss regions. By applying Gottesman-Lo two-way post-processing protocol, the entanglement PDC QKD can tolerate up to 70dB combined channel losses (35dB for each channel) provided that the PDC source is placed in between Alice and Bob. After considering statistical fluctuations, the PDC setup can tolerate up to 53dB channel losses.

  12. WRF-Chem model predictions of the regional impacts of N2O5 heterogeneous processes on night-time chemistry over north-western Europe

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lowe, Douglas; Archer-Nicholls, Scott; Morgan, Will; Allan, James D.; Utembe, Steve; Ouyang, Bin; Aruffo, Eleonora; Le Breton, Michael; Zaveri, Rahul A.; di Carlo, Piero; et al

    2015-01-01T23:59:59.000Z

    Chemical modelling studies have been conducted over north-western Europe in summer conditions, showing that night-time dinitrogen pentoxide (N2O5) heterogeneous reactive uptake is important regionally in modulating particulate nitrate and has a~modest influence on oxidative chemistry. Results from Weather Research and Forecasting model with Chemistry (WRF-Chem) model simulations, run with a detailed volatile organic compound (VOC) gas-phase chemistry scheme and the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) sectional aerosol scheme, were compared with a series of airborne gas and particulate measurements made over the UK in July 2010. Modelled mixing ratios of key gas-phase species were reasonably accurate (correlationsmore »with measurements of 0.7–0.9 for NO2 and O3). However modelled loadings of particulate species were less accurate (correlation with measurements for particulate sulfate and ammonium were between 0.0 and 0.6). Sulfate mass loadings were particularly low (modelled means of 0.5–0.7 ?g kg?1air, compared with measurements of 1.0–1.5 ?g kg?1air). Two flights from the campaign were used as test cases – one with low relative humidity (RH) (60–70%), the other with high RH (80–90%). N2O5 heterogeneous chemistry was found to not be important in the low-RH test case; but in the high-RH test case it had a strong effect and significantly improved the agreement between modelled and measured NO3 and N2O5. When the model failed to capture atmospheric RH correctly, the modelled NO3 and N2O5 mixing ratios for these flights differed significantly from the measurements. This demonstrates that, for regional modelling which involves heterogeneous processes, it is essential to capture the ambient temperature and water vapour profiles. The night-time NO3 oxidation of VOCs across the whole region was found to be 100–300 times slower than the daytime OH oxidation of these compounds. The difference in contribution was less for alkenes (× 80) and comparable for dimethylsulfide (DMS). However the suppression of NO3 mixing ratios across the domain by N2O5 heterogeneous chemistry has only a very slight, negative, influence on this oxidative capacity. The influence on regional particulate nitrate mass loadings is stronger. Night-time N2O5 heterogeneous chemistry maintains the production of particulate nitrate within polluted regions: when this process is taken into consideration, the daytime peak (for the 95th percentile) of PM10 nitrate mass loadings remains around 5.6 ?g kg?1air, but the night-time minimum increases from 3.5 to 4.6 ?g kg?1air. The sustaining of higher particulate mass loadings through the night by this process improves model skill at matching measured aerosol nitrate diurnal cycles and will negatively impact on regional air quality, requiring this process to be included in regional models.« less

  13. Long-Range Atmospheric Transport of Polycyclic Aromatic Hydrocarbons: A Global 3-D Model Analysis Including Evaluation of Arctic Sources

    E-Print Network [OSTI]

    Friedman, Carey

    We use the global 3-D chemical transport model GEOS-Chem to simulate long-range atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). To evaluate the model’s ability to simulate PAHs with different volatilities, ...

  14. Repatriation of US sources from Brazil

    SciTech Connect (OSTI)

    Tompkins, Andrew J [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    IAEA's interest in excess and unwanted sealed sources extends back to when radium sources were a problem throughout the world. Sta11ing in 1994, world wide IAEA member states inventoried and consolidated radium (Ra)-226 sources. IAEA then trained Regional Teams in the conditioning of Ra-226 sealed sources for long term storage, which resulted in the Regional Teams conditioning about 14,000 radium sources. These sources remained in their respective IAEA member state locations. Regional teams were seen as a way to encourage member state (local) management of a world wide problem, as well as a more cost effective solution.

  15. Regional refining models for alternative fuels using shale and coal synthetic crudes: identification and evaluation of optimized alternative fuels. Annual report, March 20, 1979-March 19, 1980

    SciTech Connect (OSTI)

    Sefer, N.R.; Russell, J.A.

    1980-11-01T23:59:59.000Z

    The initial phase has been completed in the project to evaluate alternative fuels for highway transportation from synthetic crudes. Three refinery models were developed for Rocky Mountain, Mid-Continent and Great Lakes regions to make future product volumes and qualities forecast for 1995. Projected quantities of shale oil and coal oil syncrudes were introduced into the raw materials slate. Product slate was then varied from conventional products to evaluate maximum diesel fuel and broadcut fuel in all regions. Gasoline supplement options were evaluated in one region for 10% each of methanol, ethanol, MTBE or synthetic naphtha in the blends along with syncrude components. Compositions and qualities of the fuels were determined for the variation in constraints and conditions established for the study. Effects on raw materials, energy consumption and investment costs were reported. Results provide the basis to formulate fuels for laboratory and engine evaluation in future phases of the project.

  16. COLLABORATIVE RESEARCH: TOWARDS ADVANCED UNDERSTANDING AND PREDICTIVE CAPABILITY OF CLIMATE CHANGE IN THE ARCTIC USING A HIGH-RESOLUTION REGIONAL ARCTIC CLIMATE SYSTEM MODEL

    SciTech Connect (OSTI)

    Gutowski, William J.

    2013-02-07T23:59:59.000Z

    The motivation for this project was to advance the science of climate change and prediction in the Arctic region. Its primary goals were to (i) develop a state-of-the-art Regional Arctic Climate system Model (RACM) including high-resolution atmosphere, land, ocean, sea ice and land hydrology components and (ii) to perform extended numerical experiments using high performance computers to minimize uncertainties and fundamentally improve current predictions of climate change in the northern polar regions. These goals were realized first through evaluation studies of climate system components via one-way coupling experiments. Simulations were then used to examine the effects of advancements in climate component systems on their representation of main physics, time-mean fields and to understand variability signals at scales over many years. As such this research directly addressed some of the major science objectives of the BER Climate Change Research Division (CCRD) regarding the advancement of long-term climate prediction.

  17. Evaluating the risk of non-point source pollution from biosolids: integrated modelling of nutrient losses at field and catchment scales Hydrol. Earth Syst. Sci., 11(1), 601613, 2007

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Evaluating the risk of non-point source pollution from biosolids: integrated modelling of nutrient the risk of non-point source pollution from biosolids: integrated modelling of nutrient losses at field catchment scale to evaluate the behaviour of biosolid-derived losses of P in agricultural systems

  18. Sandia National Laboratories: Photovoltaic Regional Testing Center...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Grid Integration, Modeling, Modeling & Analysis, News, News & Events, Partnership, Photovoltaic, Photovoltaic Regional Testing Center (PV RTC), Photovoltaic Systems Evaluation...

  19. Use of superposition and the extended pulse model to evaluate the contaminant transport parameters of variably source-loaded plumes

    E-Print Network [OSTI]

    Hankins, Donald Wayne

    1988-01-01T23:59:59.000Z

    -vt O O W 2000 1000 cm 0 500 1000 cm OO x vt ~ cbservaticn ttclnts Figure 11. Plan view of the concentration plume ' 1 d' and inc u ing the source e decreased sour th it tio di gram a 1 ana yses are demarcated. or 39 1 5. 0 14. 0 3-5 13... and dedication to science have been a great source of inspiration to me. DEDICATION vii TABLE OF CONTENTS ABSTRACT ACKNOWLEDGEMENTS DEDICATION TABLE OF CONTENTS LIST OF FIGURES 1. INTRODUCTION 2. MATHEMATICAL CONSIDERATIONS 2. 1 The Advection...

  20. Source Term Estimation of Radioxenon Released from the Fukushima Dai-ichi Nuclear Reactors Using Measured Air Concentrations and Atmospheric Transport Modeling

    SciTech Connect (OSTI)

    Eslinger, Paul W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Biegalski, S. [Univ. of Texas at Austin, TX (United States); Bowyer, Ted W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Cooper, Matthew W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Haas, Derek A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hayes, James C. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hoffman, Ian [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Korpach, E. [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Yi, Jing [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Miley, Harry S. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Rishel, Jeremy P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Ungar, R. Kurt [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); White, Brian [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Woods, Vincent T. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

    2014-01-01T23:59:59.000Z

    Systems designed to monitor airborne radionuclides released from underground nuclear explosions detected radioactive fallout from the Fukushima Daiichi nuclear accident in March 2011. Atmospheric transport modeling (ATM) of plumes of noble gases and particulates were performed soon after the accident to determine plausible detection locations of any radioactive releases to the atmosphere. We combine sampling data from multiple International Modeling System (IMS) locations in a new way to estimate the magnitude and time sequence of the releases. Dilution factors from the modeled plume at five different detection locations were combined with 57 atmospheric concentration measurements of 133-Xe taken from March 18 to March 23 to estimate the source term. This approach estimates that 59% of the 1.24×1019 Bq of 133-Xe present in the reactors at the time of the earthquake was released to the atmosphere over a three day period. Source term estimates from combinations of detection sites have lower spread than estimates based on measurements at single detection sites. Sensitivity cases based on data from four or more detection locations bound the source term between 35% and 255% of available xenon inventory.

  1. INEEL Subregional Conceptual Model Report Volume 3: Summary of Existing Knowledge of Natural and Anthropogenic Influences on the Release of Contaminants to the Subsurface Environment from Waste Source Terms at the INEEL

    SciTech Connect (OSTI)

    Paul L. Wichlacz

    2003-09-01T23:59:59.000Z

    This source-term summary document is intended to describe the current understanding of contaminant source terms and the conceptual model for potential source-term release to the environment at the Idaho National Engineering and Environmental Laboratory (INEEL), as presented in published INEEL reports. The document presents a generalized conceptual model of the sources of contamination and describes the general categories of source terms, primary waste forms, and factors that affect the release of contaminants from the waste form into the vadose zone and Snake River Plain Aquifer. Where the information has previously been published and is readily available, summaries of the inventory of contaminants are also included. Uncertainties that affect the estimation of the source term release are also discussed where they have been identified by the Source Term Technical Advisory Group. Areas in which additional information are needed (i.e., research needs) are also identified.

  2. USING THE UTAH ENERGY BALANCE SNOW MELT MODEL TO QUANTIFY SNOW AND GLACIER MELT IN THE HIMALAYAN REGION

    E-Print Network [OSTI]

    Tarboton, David

    USING THE UTAH ENERGY BALANCE SNOW MELT MODEL TO QUANTIFY SNOW AND GLACIER MELT IN THE HIMALAYAN on a distributed version of the Utah Energy Balance (UEB) snowmelt model, referred to as UEBGrid, which was adapted: glacier and snow melt, Energy balance, model, remote sensing) INTRODUCTION Countries in Hindu Kush

  3. Marine air intrusion into the Adelie Land sector of East Antarctica: A study using the regional climate model (MAR)

    E-Print Network [OSTI]

    Gallée, Hubert

    , and often, precipitation in the coastal regions. Extratropical cyclones also advect cloud cover ahead of them as they track eastward. The presence of clouds greatly effects the reflected radiation of the atmosphere. In summer their main impact is to decrease the short wave radiation coming to Earth, while

  4. Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: II. Control of the \\HII Region Parameters

    E-Print Network [OSTI]

    Michael A. Dopita; Joerg Fischera; Ralph S. Sutherland; Lisa J. Kewley; Richard J. Tuffs; Cristina C. Popescu; Wil van Breugel; Brent A. Groves; Claus Leitherer

    2006-06-22T23:59:59.000Z

    We examine, from a theoretical viewpoint, how the physical parameters of HII regions are controlled in both normal galaxies and in starburst environments. These parameters are the HII region luminosity function, the time-dependent size, the covering fraction of molecular clouds, the pressure in the ionized gas and the ionization parameter. The factors which control them are the initial mass function of the exciting stars, the cluster mass function, the metallicity and the mean pressure in the surrounding interstellar medium. We investigate the sensitivity of the H$\\alpha$ luminosity to the IMF, and find that this can translate to more than a factor two variation in derived star formation rates. The molecular cloud dissipation timescale is estimated from a case study of M17 to be $\\sim1$ Myr for this object. Based upon HII luminosity function fitting for nearby galaxies, we suggest that the \\HII region cluster mass function is fitted by a log-normal form peaking at $\\sim 100 M_{\\odot}$. The cluster mass function continues the stellar IMF to higher mass. The pressure in the HII regions is controlled by the mechanical luminosity flux from the central cluster. Since this is closely related to the ionizing photon flux, we show that the ionization parameter is not a free variable, and that the diffuse ionized medium may be composed of many large, faint and old HII regions. Finally, we derive theoretical probability distributions for the ionization parameter as a function of metallicity and compare these to those derived for SDSS galaxies.

  5. Final Technical Report for Collaborative Research: Regional climate-change projections through next-generation empirical and dynamical models, DE-FG02-07ER64429

    SciTech Connect (OSTI)

    Smyth, Padhraic [University of California, Irvine

    2013-07-22T23:59:59.000Z

    This is the final report for a DOE-funded research project describing the outcome of research on non-homogeneous hidden Markov models (NHMMs) and coupled ocean-atmosphere (O-A) intermediate-complexity models (ICMs) to identify the potentially predictable modes of climate variability, and to investigate their impacts on the regional-scale. The main results consist of extensive development of the hidden Markov models for rainfall simulation and downscaling specifically within the non-stationary climate change context together with the development of parallelized software; application of NHMMs to downscaling of rainfall projections over India; identification and analysis of decadal climate signals in data and models; and, studies of climate variability in terms of the dynamics of atmospheric flow regimes.

  6. Variable Density Flow Modeling for Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States

    SciTech Connect (OSTI)

    Joel Sminchak

    2011-09-30T23:59:59.000Z

    The Arches Province in the Midwestern U.S. has been identified as a major area for carbon dioxide (CO{sub 2}) storage applications because of the intersection of Mt. Simon sandstone reservoir thickness and permeability. To better understand large-scale CO{sub 2} storage infrastructure requirements in the Arches Province, variable density scoping level modeling was completed. Three main tasks were completed for the variable density modeling: Single-phase, variable density groundwater flow modeling; Scoping level multi-phase simulations; and Preliminary basin-scale multi-phase simulations. The variable density modeling task was successful in evaluating appropriate input data for the Arches Province numerical simulations. Data from the geocellular model developed earlier in the project were translated into preliminary numerical models. These models were calibrated to observed conditions in the Mt. Simon, suggesting a suitable geologic depiction of the system. The initial models were used to assess boundary conditions, calibrate to reservoir conditions, examine grid dimensions, evaluate upscaling items, and develop regional storage field scenarios. The task also provided practical information on items related to CO{sub 2} storage applications in the Arches Province such as pressure buildup estimates, well spacing limitations, and injection field arrangements. The Arches Simulation project is a three-year effort and part of the United States Department of Energy (U.S. DOE)/National Energy Technology Laboratory (NETL) program on innovative and advanced technologies and protocols for monitoring/verification/accounting (MVA), simulation, and risk assessment of CO{sub 2} sequestration in geologic formations. The overall objective of the project is to develop a simulation framework for regional geologic CO{sub 2} storage infrastructure along the Arches Province of the Midwestern U.S.

  7. Incorporation of aqueous reaction kinetics and biodegradation into TOUGHREACT: Application of a multi-region model to hydrobiogeoChemical transport of denitrification and sulfate reduction

    E-Print Network [OSTI]

    Xu, Tianfu

    2008-01-01T23:59:59.000Z

    Region: quartz calcite gypsum goethite Hydro- Region: Na + ,minerals gypsum and goethite were assumed to be initiallyChem-Region, Fe generated from goethite dissolution and HS

  8. Assessing the CAM5 Physics Suite in the WRF-Chem Model: Implementation, Resolution Sensitivity, and a First Evaluation for a Regional Case Study

    SciTech Connect (OSTI)

    Ma, Po-Lun; Rasch, Philip J.; Fast, Jerome D.; Easter, Richard C.; Gustafson, William I.; Liu, Xiaohong; Ghan, Steven J.; Singh, Balwinder

    2014-05-06T23:59:59.000Z

    A suite of physical parameterizations (deep and shallow convection, turbulent boundary layer, aerosols, cloud microphysics, and cloud fraction) from the global climate model Community Atmosphere Model version 5.1 (CAM5) has been implemented in the regional model Weather Research and Forecasting with chemistry (WRF-Chem). A downscaling modeling framework with consistent physics has also been established in which both global and regional simulations use the same emissions and surface fluxes. The WRF-Chem model with the CAM5 physics suite is run at multiple horizontal resolutions over a domain encompassing the northern Pacific Ocean, northeast Asia, and northwest North America for April 2008 when the ARCTAS, ARCPAC, and ISDAC field campaigns took place. These simulations are evaluated against field campaign measurements, satellite retrievals, and ground-based observations, and are compared with simulations that use a set of common WRF-Chem Parameterizations. This manuscript describes the implementation of the CAM5 physics suite in WRF-Chem provides an overview of the modeling framework and an initial evaluation of the simulated meteorology, clouds, and aerosols, and quantifies the resolution dependence of the cloud and aerosol parameterizations. We demonstrate that some of the CAM5 biases, such as high estimates of cloud susceptibility to aerosols and the underestimation of aerosol concentrations in the Arctic, can be reduced simply by increasing horizontal resolution. We also show that the CAM5 physics suite performs similarly to a set of parameterizations commonly used in WRF-Chem, but produces higher ice and liquid water condensate amounts and near-surface black carbon concentration. Further evaluations that use other mesoscale model parameterizations and perform other case studies are needed to infer whether one parameterization consistently produces results more consistent with observations.

  9. Ecosystem feedbacks to climate change in California: Development, testing, and analysis using a coupled regional atmosphere and land-surface model (WRF3-CLM3.5)

    SciTech Connect (OSTI)

    Subin, Z.M.; Riley, W.J.; Kueppers, L.M.; Jin, J.; Christianson, D.S.; Torn, M.S.

    2010-11-01T23:59:59.000Z

    A regional atmosphere model [Weather Research and Forecasting model version 3 (WRF3)] and a land surface model [Community Land Model, version 3.5 (CLM3.5)] were coupled to study the interactions between the atmosphere and possible future California land-cover changes. The impact was evaluated on California's climate of changes in natural vegetation under climate change and of intentional afforestation. The ability of WRF3 to simulate California's climate was assessed by comparing simulations by WRF3-CLM3.5 and WRF3-Noah to observations from 1982 to 1991. Using WRF3-CLM3.5, the authors performed six 13-yr experiments using historical and future large-scale climate boundary conditions from the Geophysical Fluid Dynamics Laboratory Climate Model version 2.1 (GFDL CM2.1). The land-cover scenarios included historical and future natural vegetation from the Mapped Atmosphere-Plant-Soil System-Century 1 (MC1) dynamic vegetation model, in addition to a future 8-million-ha California afforestation scenario. Natural vegetation changes alone caused summer daily-mean 2-m air temperature changes of -0.7 to +1 C in regions without persistent snow cover, depending on the location and the type of vegetation change. Vegetation temperature changes were much larger than the 2-m air temperature changes because of the finescale spatial heterogeneity of the imposed vegetation change. Up to 30% of the magnitude of the summer daily-mean 2-m air temperature increase and 70% of the magnitude of the 1600 local time (LT) vegetation temperature increase projected under future climate change were attributable to the climate-driven shift in land cover. The authors projected that afforestation could cause local 0.2-1.2 C reductions in summer daily-mean 2-m air temperature and 2.0-3.7 C reductions in 1600 LT vegetation temperature for snow-free regions, primarily because of increased evapotranspiration. Because some of these temperature changes are of comparable magnitude to those projected under climate change this century, projections of climate and vegetation change in this region need to consider these climate-vegetation interactions.

  10. Statistical Modelling of the Relationship Between Main Development Region Sea Surface Temperature and Atlantic Basin Hurricane Numbers

    E-Print Network [OSTI]

    Binter, R; Khare, S; Binter, Roman; Jewson, Stephen; Khare, Shree

    2007-01-01T23:59:59.000Z

    We are building a hurricane number prediction scheme that relies, in part, on statistical modelling of the empirical relationship between Atlantic sea surface temperatures and Atlantic basin hurricane numbers. We test out a number of simple statistical models for this relationship, using data from 1900 to 2005 and data from 1950 to 2005, and for both all hurricane numbers and intense hurricane numbers.

  11. Preliminary geohydrologic conceptual model of the Los Medanos region near the Waste Isolation Pilot Plant for the purpose of performance assessment

    SciTech Connect (OSTI)

    Brinster, K.F. (Science Applications International Corp., Albuquerque, NM (USA))

    1991-01-01T23:59:59.000Z

    This report describes a geohydrologic conceptual model of the northern Delaware Basin to be used in modeling three-dimensional, regional ground-water flow for assessing the performance of the Waste Isolation Pilot Plant (WIPP) in the Los Medanos region near Carlsbad, New Mexico. Geochemical and hydrological evidence indicates that flow is transient in the Rustler Formation and the Capitan aquifer in response to changing geologic, hydrologic, and climatic conditions. Before the Pleistocene, ground-water flow in the Rustler Formation was generally eastward, but uneven tilting of the Delaware Basin lowered the regional base level and formed fractures in the evaporitic sequence of rocks approximately parallel to the basin axis. Dissolution along the fractures, coupled with erosion, formed Nash Draw. Also, the drop in base level resulted in an increase in the carrying power of the Pecos River, which began incising the Capitan/aquifer near Carlsbad, New Mexico. Erosion and downcutting released hydraulic pressure that caused a reversal in Rustler ground-water flow direction near the WIPP. Flow in the Rustler west of the WIPP is toward Nash Draw and eventually toward Malaga Bend; flow south of the WIPP is toward Malaga Bend. 126 refs., 70 figs., 18 tabs.

  12. PlasmaSourcesSci.Technol. 4 (1995)317-331. Printed in the UK I A two-region model of a radiofrequency

    E-Print Network [OSTI]

    Economou, Demetre J.

    Plasma Processing Laboratory, Department of Chemical Engineering, Universityof Houston, Houston, TX 77:. On the other hand, low pressure, high power and/or small y resulted in a large degree of gas dissociation kii k8r,j recombination rate coefficient on k,, rate coefficient for volume L m electron mass (g) Mi

  13. Specifications for the development of a fully three-dimensional numerical groundwater model for regional mass transport of radionuclides from a deep waste repository

    SciTech Connect (OSTI)

    Prickett, T.A.

    1980-04-01T23:59:59.000Z

    Specifications are given which are necessary to develop a three-dimensional numerical model capable of simulating regional mass transport of radionuclides from a deep waste repository. The model to be developed will include all of the significant mass transport processes including flow, chemical, and thermal advection, mechanical dispersion, molecular diffusion, ion exchange reactions, and radioactive decay. The model specifications also include that density and viscosity fluid properties be functions of pressure, temperature, and concentration and take into account fluid and geologic heterogenieties by allowing possible assignment of individual values to every block of the model. The model specifications furthermore include the repository shape, input/output information, boundary conditions, and the need for documentation and a user's manual. Model code validation can be accomplished with the included known analytical or laboratory solutions. It is recommended that an existing finite-difference model (developed by INTERCOMP and INTERA, Inc.) be used as a starting point either as an acceptable basic code for modification or as a pattern for the development of a completely different numerical scheme. A ten-step plan is given to outline the general procedure for development of the code.

  14. Conceptual Model Summary Report Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States

    SciTech Connect (OSTI)

    None

    2011-06-30T23:59:59.000Z

    A conceptual model was developed for the Arches Province that integrates geologic and hydrologic information on the Eau Claire and Mt. Simon formations into a geocellular model. The conceptual model describes the geologic setting, stratigraphy, geologic structures, hydrologic features, and distribution of key hydraulic parameters. The conceptual model is focused on the Mt. Simon sandstone and Eau Claire formations. The geocellular model depicts the parameters and conditions in a numerical array that may be imported into the numerical simulations of carbon dioxide (CO{sub 2}) storage. Geophysical well logs, rock samples, drilling logs, geotechnical test results, and reservoir tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. The geologic and hydraulic data were integrated into a three-dimensional (3D) grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data were corrected in locations where reservoir tests have been performed in Mt. Simon injection wells. The final geocellular model covers an area of 600 km by 600 km centered on the Arches Province. The geocellular model includes a total of 24,500,000 cells representing estimated porosity and permeability distribution. CO{sub 2} injection scenarios were developed for on-site and regional injection fields at rates of 70 to 140 million metric tons per year.

  15. Spatial Distribution of the Plasma Characteristics of a Tandem Plasma Source

    SciTech Connect (OSTI)

    Paunska, Tsvetelina V.; Shivarova, Antonia P.; Tsankov, Tsanko V. [Faculty of Physics, Sofia University, BG-1164 Sofia (Bulgaria); Tarnev, Khristo Ts. [Department of Applied Physics, Technical University-Sofia, BG-1000 Sofia (Bulgaria)

    2009-03-12T23:59:59.000Z

    The study presents results from a 2D model of hydrogen discharges in a tandem type of a plasma source. Analysis of the particle and electron-energy balance outlines the pattern of the source operation: (i) discharge production in the driver governed by the mechanisms ensuring self-consistency of hydrogen discharges in regions with rf power deposition, however, here influenced by the fluxes going to the second chamber of the source, and (ii) plasma existence in the expansion volume of the source completely determined by the particle fluxes from the first chamber. The influence of varying applied power and gas pressure is discussed.

  16. Modeling of ns and ps laser-induced soft X-ray sources using nitrogen gas puff target

    SciTech Connect (OSTI)

    Vrba, P., E-mail: vrba@ipp.cas.cz [Institute of Plasma Physics, Academy of Sciences, Za Slovankou 3, Prague 8 (Czech Republic); Vrbova, M. [Faculty of Biomedical Engineering, CTU in Prague, Sitna 3105, Kladno 2 (Czech Republic); Zakharov, S. V. [EPPRA sas, Villebon/Yvette (France); Zakharov, V. S. [EPPRA sas, Villebon/Yvette (France); KIAM RAS, Moscow (Russian Federation)

    2014-07-15T23:59:59.000Z

    Gas puff laser plasma is studied as a source of water window radiation with 2.88?nm wavelength, corresponding to quantum transition 1s{sup 2} ? 1s2p of helium-like nitrogen ions. Spatial development of plasma induced by Nd:YAG laser beam is simulated by 2D Radiation-Magneto-Hydro-Dynamic code Z*. The results for nitrogen gas layer (0.72?mm thickness, 1?bar pressure) and two different laser pulses (600 mJ/7?ns and 525 mJ/170 ps), corresponding to the experiments done in Laser Laboratory Gottingen are presented.

  17. Active manipulation of fields modeled by the Helmholtz Daniel Onofrei

    E-Print Network [OSTI]

    Onofrei, Daniel

    Active manipulation of fields modeled by the Helmholtz equation Daniel Onofrei May 27, 2014, now exterior active sources, modeled with the help of the above boundary controls (which can represent of active control in the context of scalar Helmholtz equation. Given a source region Da and {v0, v1, ..., vn

  18. Active manipulation of fields modeled by the Helmholtz Daniel Onofrei

    E-Print Network [OSTI]

    Onofrei, Daniel

    Active manipulation of fields modeled by the Helmholtz equation Daniel Onofrei October 27, 2014 exterior active sources, modeled with the help of the above boundary controls (which can represent velocity]) uses a discrete number of active sources located in the exterior of the control region to manipulate

  19. Evaluation of the accuracy of the EPA model for BOD5 prediction in various climatic regions of Texas

    E-Print Network [OSTI]

    Koutny, Jessica Leigh

    2000-01-01T23:59:59.000Z

    This project focused on evaluating the effectiveness of the EPA's first-order BOD? removal model for predicting BOD? reductions in residential constructed wetlands. Monthly grab sample data from nine constructed wetlands designed using the EPA BOD5...

  20. Statistical Modelling of the Relationship Between Main Development Region Sea Surface Temperature and \\emph{Landfalling} Atlantic Basin Hurricane Numbers

    E-Print Network [OSTI]

    Binter, R; Khare, S; Binter, Roman; Jewson, Stephen; Khare, Shree

    2007-01-01T23:59:59.000Z

    We are building a hurricane number prediction scheme that relies, in part, on statistical modelling of the empirical relationship between Atlantic sea surface temperatures and landfalling hurricane numbers. We test out a number of simple statistical models for that relationship, using data from 1900 to 2005 and data from 1950 to 2005, and for both all hurricane numbers and intense hurricane numbers. The results are very different from the corresponding analysis for basin hurricane numbers.

  1. Use of multi-sources 10-years quantitative precipitation estimation re-analyses in a lumped rainfall-runoff model.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of precipitation depths. Indeed, meteorological radar provides spatially distributed rainfall depths information (radars, hourly and daily rain gauges, satellite data, model freezing level heights, etc with rain gauge network. First, a methodology for automated identification and treatment of radar

  2. Rutgers Regional Report # Regional Report

    E-Print Network [OSTI]

    Garfunkel, Eric

    , population, income, and building permits over a 32-year period from 1969 to 2001 for the 31-county Tri counties of the Tri-State (Connecticut, New Jersey, and New York) Region have been divided for analytical the nation and the Tri-State Region. What has not been fully documented, however, is the apparent shift

  3. Potential Economic Impacts from Offshore Wind in the Gulf of Mexico Region (Fact Sheet)

    SciTech Connect (OSTI)

    Flores, F.; Keyser, D.; Tegen, S.

    2014-01-01T23:59:59.000Z

    Offshore wind is a clean, renewable source of energy and can be an economic driver in the United States. To better understand the employment opportunities and other potential regional economic impacts from offshore wind development, the U.S. Department of Energy (DOE) funded research that focuses on four regions of the country. The studies use multiple scenarios with various local job and domestic manufacturing content assumptions. Each regional study uses the new offshore wind Jobs and Economic Development Impacts (JEDI) model, developed by the National Renewable Energy Laboratory. This fact sheet summarizes the potential economic impacts for the Gulf of Mexico region.

  4. Potential Economic Impacts from Offshore Wind in the Great Lakes Region (Fact Sheet)

    SciTech Connect (OSTI)

    Tegen, S.; Keyser, D.

    2014-01-01T23:59:59.000Z

    Offshore wind is a clean, renewable source of energy and can be an economic driver in the United States. To better understand the employment opportunities and other potential regional economic impacts from offshore wind development, the U.S. Department of Energy (DOE) funded research that focuses on four regions of the country. The studies use multiple scenarios with various local job and domestic manufacturing content assumptions. Each regional study uses the new offshore wind Jobs and Economic Development Impacts (JEDI) model, developed by DOE's National Renewable Energy Laboratory. This fact sheet summarizes the potential economic impacts identified by the study for the Great Lakes region.

  5. Potential Economic Impacts from Offshore Wind in the Mid-Atlantic Region (Fact Sheet)

    SciTech Connect (OSTI)

    Keyser, D.; Tegen, S.; Flores, F.; Zammit, D.; Kraemer, M.; Miles, J.

    2014-01-01T23:59:59.000Z

    Offshore wind is a clean, renewable source of energy and can be an economic driver in the United States. To better understand the employment opportunities and other potential regional economic impacts from offshore wind development, the U.S. Department of Energy (DOE) funded research that focuses on four regions of the country. The studies use multiple scenarios with various local job and domestic manufacturing content assumptions. Each regional study uses the new offshore wind Jobs and Economic Development Impacts (JEDI) model, developed by the National Renewable Energy Laboratory. This fact sheet summarizes the potential economic impacts for the Mid-Atlantic region.

  6. Eddy Fluxes and Sensitivity of the Water Cycle to Spatial Resolution in Idealized Regional Aquaplanet Model Simulations

    SciTech Connect (OSTI)

    Hagos, Samson M.; Leung, Lai-Yung R.; Gustafson, William I.; Singh, Balwinder

    2014-02-28T23:59:59.000Z

    A multi-scale moisture budget analysis is used to identify the mechanisms responsible for the sensitivity of the water cycle to spatial resolution using idealized regional aquaplanet simulations. In the higher resolution simulations, moisture transport by eddies fluxes dry the boundary layer enhancing evaporation and precipitation. This effect of eddies, which is underestimated by the physics parameterizations in the low-resolution simulations, is found to be responsible for the sensitivity of the water cycle both directly, and through its upscale effect, on the mean circulation. Correlations among moisture transport by eddies at adjacent ranges of scales provides the potential for reducing this sensitivity by representing the unresolved eddies by their marginally resolved counterparts.

  7. High current ion source

    DOE Patents [OSTI]

    Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); MacGill, Robert A. (645 Kern St., Richmond, CA 94805); Galvin, James E. (2 Commodore Dr. #276, Emeryville, CA 94608)

    1990-01-01T23:59:59.000Z

    An ion source utilizing a cathode and anode for producing an electric arc therebetween. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma leaves the generation region and expands through another regon. The density profile of the plasma may be flattened using a magnetic field formed within a vacuum chamber. Ions are extracted from the plasma to produce a high current broad on beam.

  8. Source apportionment of airborne particulate matter for the speciation trends network site in Cleveland, OH

    SciTech Connect (OSTI)

    Liming Zhou; Philip K. Hopke; Weixiang Zhao [Clarkson University, Potsdam, NY (United States). Center for Air Resources Engineering and Science

    2009-03-15T23:59:59.000Z

    Aerosol composition data from the Speciation Trends Network (STN) site (East 14th Street) in Cleveland, OH, were analyzed by advanced receptor model methods for source apportionment as well as by the standard positive matrix factorization (PMF) using PMF2. These different models are used in combination to test model limitations. These data were 24-hr average mass concentrations and compositions obtained for samples taken every third day from 2001 to 2003. The Multilinear Engine (ME) was used to solve an expanded model to estimate the source profiles and source contributions and also to investigate the wind speed, wind direction, time-of-day, weekend/weekday, and seasonal effects. PMF2 was applied to the same dataset. Potential source contribution function (PSCF) and conditional probability function (CPF) analyses were used to locate the regional and local sources using the resolved source contributions and appropriate meteorological data. Very little difference was observed between the results of the expanded model and the PMF2 values for the profiles and source contribution time series. The identified sources were as ferrous smelter, secondary sulfate, secondary nitrate, soil/combustion mixture, steel mill, traffic, wood smoke, and coal burning. The CPF analysis was useful in helping to identify local sources, whereas the PSCF results were only useful for regional source areas. Both of these analyses were more useful than the wind directional factor derived from the expanded factor analysis. However, the expanded analysis provided direct information on seasonality and day-of-week behavior of the sources. 28 refs., 8 figs., 4 tabs.

  9. Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01T23:59:59.000Z

    in running RCM’s over Greenland to produce high-qualityoutlet glaciers. For Greenland, this detail is specificallyCurrently, no coupled Greenland Ice Sheet model experiment

  10. A Stochastic Optimization Case Study using ILOG CPLEX Concert Technology: Dual Sourcing Model for Managing Supply Chain Disruptions

    E-Print Network [OSTI]

    Bjørnstad, Ottar Nordal

    of a company under uncertainty is proposed in this study. Deterministic planning and scheduling models is optimal usage of future resources on the basis of available present information and future scenarios1 increase. As simple as uncertain lead time can affect the production plans which necessitates

  11. Controlled-source electromagnetic modeling of the masking effect of marine gas hydrate on a deeper hydrocarbon reservoir

    E-Print Network [OSTI]

    Dickins, David

    2009-06-02T23:59:59.000Z

    that electric field data were reliable to roughly 5000 m of TX-RX offset for the 1 Hz and 3 Hz cases, and to 6500 m offset for 10 Hz. The gas hydrate/hydrocarbon model was then run with zero-value boundary conditions. The goal was to determine what effect...

  12. Commercial Building Energy Baseline Modeling Software: Performance Metrics and Method Testing with Open Source Models and Implications for Proprietary Software Testing

    SciTech Connect (OSTI)

    Price, Phillip N.; Granderson, Jessica; Sohn, Michael; Addy, Nathan; Jump, David

    2013-09-01T23:59:59.000Z

    The overarching goal of this work is to advance the capabilities of technology evaluators in evaluating the building-level baseline modeling capabilities of Energy Management and Information System (EMIS) software. Through their customer engagement platforms and products, EMIS software products have the potential to produce whole-building energy savings through multiple strategies: building system operation improvements, equipment efficiency upgrades and replacements, and inducement of behavioral change among the occupants and operations personnel. Some offerings may also automate the quantification of whole-building energy savings, relative to a baseline period, using empirical models that relate energy consumption to key influencing parameters, such as ambient weather conditions and building operation schedule. These automated baseline models can be used to streamline the whole-building measurement and verification (M&V) process, and therefore are of critical importance in the context of multi-measure whole-building focused utility efficiency programs. This report documents the findings of a study that was conducted to begin answering critical questions regarding quantification of savings at the whole-building level, and the use of automated and commercial software tools. To evaluate the modeling capabilities of EMIS software particular to the use case of whole-building savings estimation, four research questions were addressed: 1. What is a general methodology that can be used to evaluate baseline model performance, both in terms of a) overall robustness, and b) relative to other models? 2. How can that general methodology be applied to evaluate proprietary models that are embedded in commercial EMIS tools? How might one handle practical issues associated with data security, intellectual property, appropriate testing ‘blinds’, and large data sets? 3. How can buildings be pre-screened to identify those that are the most model-predictable, and therefore those whose savings can be calculated with least error? 4. What is the state of public domain models, that is, how well do they perform, and what are the associated implications for whole-building measurement and verification (M&V)? Additional project objectives that were addressed as part of this study include: (1) clarification of the use cases and conditions for baseline modeling performance metrics, benchmarks and evaluation criteria, (2) providing guidance for determining customer suitability for baseline modeling, (3) describing the portfolio level effects of baseline model estimation errors, (4) informing PG&E’s development of EMIS technology product specifications, and (5) providing the analytical foundation for future studies about baseline modeling and saving effects of EMIS technologies. A final objective of this project was to demonstrate the application of the methodology, performance metrics, and test protocols with participating EMIS product vendors.

  13. Modeling Improvements for Air Source Heat Pumps using Different Expansion Devices at Varied Charge Levels Part II

    SciTech Connect (OSTI)

    Shen, Bo [ORNL

    2011-01-01T23:59:59.000Z

    This paper describes steady-state performance simulations performed on a 3-ton R-22 split heat pump in heating mode. In total, 150 steady-state points were simulated, which covers refrigerant charge levels from 70 % to 130% relative to the nominal value, the outdoor temperatures at 17 F (-8.3 C), 35 F (1.7 C) and 47 F (8.3 C), indoor air flow rates from 60% to 150% of the rated air flow rate, and two types of expansion devices (fixed orifice and thermostatic expansion valve). A charge tuning method, which is to calibrate the charge inventory model based on measurements at two operation conditions, was applied and shown to improve the system simulation accuracy significantly in an extensive range of charge levels. In addition, we discuss the effects of suction line accumulator in modeling a heat pump system using either a fixed orifice or thermal expansion valve. Last, we identify the issue of refrigerant mass flow mal-distribution at low charge levels and propose an improved modeling approach.

  14. Modeling and analysis framework for core damage propagation during flow-blockage-initiated accidents in the Advanced Neutron Source Reactor at Oak Ridge National Laboratory

    SciTech Connect (OSTI)

    Kim, S.H.; Taleyarkhan, R.P.; Navarro-Valenti, S.; Georgevich, V.

    1995-09-01T23:59:59.000Z

    This paper describes modeling and analysis to evaluate the extent of core damage during flow blockage events in the Advanced Neutron Source (ANS) reactor planned to be built at the Oak Ridge National Laboratory (ORNL). Damage propagation is postulated to occur from thermal conduction between damaged and undamaged plates due to direct thermal contact. Such direct thermal contact may occur because of fuel plate swelling during fission product vapor release or plate buckling. Complex phenomena of damage propagation were modeled using a one-dimensional heat transfer model. A scoping study was conducted to learn what parameters are important for core damage propagation, and to obtain initial estimates of core melt mass for addressing recriticality and steam explosion events. The study included investigating the effects of the plate contact area, the convective heat transfer coefficient, thermal conductivity upon fuel swelling, and the initial temperature of the plate being contacted by the damaged plate. Also, the side support plates were modeled to account for their effects on damage propagation. The results provide useful insights into how various uncertain parameters affect damage propagation.

  15. A Comparative SWOT Analysis of the National Agricultural Extension Program Organization to Determine Best-Fit Program Model: A Case Study of the North West and South West Regions of Cameroon.

    E-Print Network [OSTI]

    Nyambi, Gwendoline

    2012-07-16T23:59:59.000Z

    A COMPARATIVE SWOT ANALYSIS OF THE NATIONAL AGRICULTURAL EXTENSION PROGRAM ORGANIZATION TO DETERMINE BEST-FIT PROGRAM MODEL: A CASE STUDY OF THE NORTH WEST AND SOUTH WEST REGIONS OF CAMEROON A Dissertation by GWENDOLINE NA-AH NYAMBI... A Comparative SWOT Analysis of the National Agricultural Extension Program Organization to Determine Best-Fit Program Model: A Case Study of the North West and South West Regions of Cameroon Copyright 2012 Gwendoline Na-ah Nyambi A COMPARATIVE...

  16. National and Regional Water and Wastewater Rates For Use inCost-Benefit Models and Evaluations of Water Efficiency Programs

    SciTech Connect (OSTI)

    Fisher, Diane C.; Whitehead, Camilla Dunham; Melody, Moya

    2006-09-01T23:59:59.000Z

    Calculating the benefits and costs of water conservation orefficiency programs requires knowing the marginal cost of the water andwastewater saved by those programs. Developing an accurate picture of thepotential cost savings from water conservation requires knowing the costof the last few units of water consumed or wastewater released, becausethose are the units that would be saved by increased water efficiency.This report describes the data we obtained on water and wastewater ratesand costs, data gaps we identified, and other issues related to using thedata to estimate the cost savings that might accrue from waterconservation programs. We identified three water and wastewater ratesources. Of these, we recommend using Raftelis Financial Corporation(RFC) because it: a) has the most comprehensive national coverage; and b)provides greatest detail on rates to calculate marginal rates. The figurebelow shows the regional variation in water rates for a range ofconsumption blocks. Figure 1A Marginal Rates of Water Blocks by Regionfrom RFC 2004Water and wastewater rates are rising faster than the rateof inflation. For example, from 1996 to 2004 the average water rateincreased 39.5 percent, average wastewater rate increased 37.8 percent,the CPI (All Urban) increased 20.1 percent, and the CPI (Water andSewerage Maintenance) increased 31.1 percent. On average, annualincreases were 4.3 percent for water and 4.1 percent for wastewater,compared to 2.3 percent for the All Urban CPI and 3.7 percent for the CPIfor water and sewerage maintenance. If trends in rates for water andwastewater rates continue, water-efficient products will become morevaluable and more cost-effective.

  17. USING STRUCTURAL EQUATIONS MODELLING TO UNRAVEL THE INFLUENCE OF LAND USE PATTERNS ON TRAVEL BEHAVIOR OF URBAN ADULT WORKERS OF PUGET SOUND REGION

    E-Print Network [OSTI]

    de Abreu e Silva, João; Goulias, Konstadinos G.

    2008-01-01T23:59:59.000Z

    behavior observation in the Puget Sound region: sampleHighway Administration and the Puget Sound Regional Council,OF URBAN ADULT WORKERS OF PUGET SOUND REGION João de Abreu e

  18. Using Structural Equations Modelling to Unravel the Influence of Land Use Patterns on Travel Behavior of Urban Adult Workers of Puget Sound Region

    E-Print Network [OSTI]

    e Silva, Joao de Abreu; Goulias, Konstadinos G.

    2008-01-01T23:59:59.000Z

    behavior observation in the Puget Sound region: sampleHighway Administration and the Puget Sound Regional Council,OF URBAN ADULT WORKERS OF PUGET SOUND REGION João de Abreu e

  19. Semianalytical quantum model for graphene field-effect transistors

    SciTech Connect (OSTI)

    Pugnaghi, Claudio; Grassi, Roberto, E-mail: roberto.grassi@unibo.it; Gnudi, Antonio; Di Lecce, Valerio; Gnani, Elena; Reggiani, Susanna; Baccarani, Giorgio [ARCES and DEI, University of Bologna, Viale Risorgimento 2, 40136 Bologna (Italy)

    2014-09-21T23:59:59.000Z

    We develop a semianalytical model for monolayer graphene field-effect transistors in the ballistic limit. Two types of devices are considered: in the first device, the source and drain regions are doped by charge transfer with Schottky contacts, while, in the second device, the source and drain regions are doped electrostatically by a back gate. The model captures two important effects that influence the operation of both devices: (i) the finite density of states in the source and drain regions, which limits the number of states available for transport and can be responsible for negative output differential resistance effects, and (ii) quantum tunneling across the potential steps at the source-channel and drain-channel interfaces. By comparison with a self-consistent non-equilibrium Green's function solver, we show that our model provides very accurate results for both types of devices, in the bias region of quasi-saturation as well as in that of negative differential resistance.

  20. Non-linear force-free field modeling of a solar active region around the time of a major flare and coronal mass ejection

    E-Print Network [OSTI]

    C. J. Schrijver; M. L. DeRosa; T. Metcalf; G. Barnes; B. Lites; T. Tarbell; J. McTiernan; G. Valori; T. Wiegelmann; M. S. Wheatland; T. Amari; G. Aulanier; P. Demoulin; M. Fuhrmann; K. Kusano; S. Regnier; J. K. Thalmann

    2007-11-30T23:59:59.000Z

    Solar flares and coronal mass ejections are associated with rapid changes in field connectivity and powered by the partial dissipation of electrical currents in the solar atmosphere. A critical unanswered question is whether the currents involved are induced by the motion of pre-existing atmospheric magnetic flux subject to surface plasma flows, or whether these currents are associated with the emergence of flux from within the solar convective zone. We address this problem by applying state-of-the-art nonlinear force-free field (NLFFF) modeling to the highest resolution and quality vector-magnetographic data observed by the recently launched Hinode satellite on NOAA Active Region 10930 around the time of a powerful X3.4 flare. We compute 14 NLFFF models with 4 different codes and a variety of boundary conditions. We find that the model fields differ markedly in geometry, energy content, and force-freeness. We discuss the relative merits of these models in a general critique of present abilities to model the coronal magnetic field based on surface vector field measurements. For our application in particular, we find a fair agreement of the best-fit model field with the observed coronal configuration, and argue (1) that strong electrical currents emerge together with magnetic flux preceding the flare, (2) that these currents are carried in an ensemble of thin strands, (3) that the global pattern of these currents and of field lines are compatible with a large-scale twisted flux rope topology, and (4) that the ~10^32 erg change in energy associated with the coronal electrical currents suffices to power the flare and its associated coronal mass ejection.

  1. Soil Carbon Change and Net Energy Associated with Biofuel Production on Marginal Lands: A Regional Modeling Perspective

    SciTech Connect (OSTI)

    Bandaru, Varaprasad; Izaurralde, Roberto C.; Manowitz, David H.; Link, Robert P.; Zhang, Xuesong; Post, W. M.

    2013-12-01T23:59:59.000Z

    The use of marginal lands (MLs) for biofuel production has been contemplated as a promising solution for meeting biofuel demands. However, there have been concerns with spatial location of MLs, their inherent biofuel potential, and possible environmental consequences with the cultivation of energy crops. Here, we developed a new quantitative approach that integrates high-resolution land cover and land productivity maps and uses conditional probability density functions for analyzing land use patterns as a function of land productivity to classify the agricultural lands. We subsequently applied this method to determine available productive croplands (P-CLs) and non-crop marginal lands (NC-MLs) in a nine-county Southern Michigan. Furthermore, Spatially Explicit Integrated Modeling Framework (SEIMF) using EPIC (Environmental Policy Integrated Climate) was used to understand the net energy (NE) and soil organic carbon (SOC) implications of cultivating different annual and perennial production systems.

  2. Northeast Regional Biomass Program

    SciTech Connect (OSTI)

    Lusk, P.D.

    1992-12-01T23:59:59.000Z

    The Northeast Regional Biomass Program has been in operation for a period of nine years. During this time, state managed programs and technical programs have been conducted covering a wide range of activities primarily aim at the use and applications of wood as a fuel. These activities include: assessments of available biomass resources; surveys to determine what industries, businesses, institutions, and utility companies use wood and wood waste for fuel; and workshops, seminars, and demonstrations to provide technical assistance. In the Northeast, an estimated 6.2 million tons of wood are used in the commercial and industrial sector, where 12.5 million cords are used for residential heating annually. Of this useage, 1504.7 mw of power has been generated from biomass. The use of wood energy products has had substantial employment and income benefits in the region. Although wood and woodwaste have received primary emphasis in the regional program, the use of municipal solid waste has received increased emphasis as an energy source. The energy contribution of biomass will increase as potentia users become more familiar with existing feedstocks, technologies, and applications. The Northeast Regional Biomass Program is designed to support region-specific to overcome near-term barriers to biomass energy use.

  3. Multi-epoch very long baseline interferometric observations of the nuclear starburst region of NGC 253: Improved modeling of the supernova and star formation rates

    SciTech Connect (OSTI)

    Rampadarath, H.; Morgan, J. S.; Tingay, S. J. [International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, WA (Australia); Lenc, E., E-mail: hayden.rampadarath@icrar.org [Sydney Institute for Astronomy, School of Physics, The University of Sydney, NSW (Australia)

    2014-01-01T23:59:59.000Z

    The results of multi-epoch observations of the southern starburst galaxy, NGC 253, with the Australian Long Baseline Array at 2.3 GHz are presented. As with previous radio interferometric observations of this galaxy, no new sources were discovered. By combining the results of this survey with Very Large Array observations at higher frequencies from the literature, spectra were derived and a free-free absorption model was fitted of 20 known sources in NGC 253. The results were found to be consistent with previous studies. The supernova remnant, 5.48-43.3, was imaged with the highest sensitivity and resolution to date, revealing a two-lobed morphology. Comparisons with previous observations of similar resolution give an upper limit of 10{sup 4} km s{sup –1} for the expansion speed of this remnant. We derive a supernova rate of <0.2 yr{sup –1} for the inner 300 pc using a model that improves on previous methods by incorporating an improved radio supernova peak luminosity distribution and by making use of multi-wavelength radio data spanning 21 yr. A star formation rate of SFR(M ? 5 M {sub ?}) < 4.9 M {sub ?} yr{sup –1} was also estimated using the standard relation between supernova and star formation rates. Our improved estimates of supernova and star formation rates are consistent with studies at other wavelengths. The results of our study point to the possible existence of a small population of undetected supernova remnants, suggesting a low rate of radio supernova production in NGC 253.

  4. Understanding Spatial and Spectral Morphologies of Ultracompact H II Regions

    SciTech Connect (OSTI)

    Peters, Thomas; /ZAH, Heidelberg; Mac Low, Mordecai-Mark; /Amer. Museum Natural Hist. /Heidelberg, Max Planck Inst. Astron.; Banerjee, Robi; /ZAH, Heidelberg; Klessen, Ralf S.; /ZAH, Heidelberg /KIPAC, Menlo Park; Dullemond, Cornelis P.; /Heidelberg, Max Planck Inst. Astron.

    2010-08-25T23:59:59.000Z

    The spatial morphology, spectral characteristics, and time variability of ultracompact H II regions provide strong constraints on the process of massive star formation. We have performed simulations of the gravitational collapse of rotating molecular cloud cores, including treatments of the propagation of ionizing and non-ionizing radiation. We here present synthetic radio continuum observations of H II regions from our collapse simulations, to investigate how well they agree with observation, and what we can learn about how massive star formation proceeds. We find that intermittent shielding by dense filaments in the gravitationally unstable accretion flow around the massive star leads to highly variable H II regions that do not grow monotonically, but rather flicker, growing and shrinking repeatedly. This behavior appears able to resolve the well-known lifetime problem. We find that multiple ionizing sources generally form, resulting in groups of ultracompact H II regions, consistent with observations. We confirm that our model reproduces the qualitative H II region morphologies found in surveys, with generally consistent relative frequencies. We also find that simulated spectral energy distributions (SEDs) from our model are consistent with the range of observed H II region SEDs, including both regions showing a normal transition from optically thick to optically thin emission, and those with intermediate spectral slopes. In our models, anomalous slopes are solely produced by inhomogeneities in the H II region, with no contribution from dust emission at millimeter or submillimeter wavelengths. We conclude that many observed characteristics of ultracompact H II regions appear consistent with massive star formation in fast, gravitationally unstable, accretion flows.

  5. UNDERSTANDING SPATIAL AND SPECTRAL MORPHOLOGIES OF ULTRACOMPACT H II REGIONS

    SciTech Connect (OSTI)

    Peters, Thomas; Banerjee, Robi; Klessen, Ralf S. [Zentrum fuer Astronomie der Universitaet Heidelberg, Institut fuer Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Low, Mordecai-Mark Mac [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, New York 10024-5192 (United States); Dullemond, Cornelis P., E-mail: thomas.peters@ita.uni-heidelberg.d [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

    2010-08-10T23:59:59.000Z

    The spatial morphology, spectral characteristics, and time variability of ultracompact (UC) H II regions provide strong constraints on the process of massive star formation. We have performed simulations of the gravitational collapse of rotating molecular cloud cores, including treatments of the propagation of ionizing and non-ionizing radiation. We here present synthetic radio continuum observations of H II regions from our collapse simulations, to investigate how well they agree with observation, and what we can learn about how massive star formation proceeds. We find that intermittent shielding by dense filaments in the gravitationally unstable accretion flow around the massive star leads to highly variable H II regions that do not grow monotonically, but rather flicker, growing and shrinking repeatedly. This behavior appears to be able to resolve the well-known lifetime problem. We find that multiple ionizing sources generally form, resulting in groups of UC H II regions, consistent with observations. We confirm that our model reproduces the qualitative H II region morphologies found in surveys, with generally consistent relative frequencies. We also find that simulated spectral energy distributions (SEDs) from our model are consistent with the range of observed H II region SEDs, including both regions showing a normal transition from optically thick to optically thin emission, and those with intermediate spectral slopes. In our models, anomalous slopes are solely produced by inhomogeneities in the H II region, with no contribution from dust emission at millimeter or submillimeter wavelengths. We conclude that many observed characteristics of UC H II regions appear consistent with massive star formation in fast, gravitationally unstable, accretion flows.

  6. SIMULATION MODEL ANALYSIS OF THE MOST PROMISING GEOLOGIC SEQUESTRATION FORMATION CANDIDATES IN THE ROCKY MOUNTAIN REGION, USA, WITH FOCUS ON UNCERTAINTY ASSESSMENT

    SciTech Connect (OSTI)

    Lee, Si-Yong; Zaluski, Wade; Will, Robert; Eisinger, Chris; Matthews, Vince; McPherson, Brian

    2013-09-01T23:59:59.000Z

    The purpose of this report is to report results of reservoir model simulation analyses for forecasting subsurface CO2 storage capacity estimation for the most promising formations in the Rocky Mountain region of the USA. A particular emphasis of this project was to assess uncertainty of the simulation-based forecasts. Results illustrate how local-scale data, including well information, number of wells, and location of wells, affect storage capacity estimates and what degree of well density (number of wells over a fixed area) may be required to estimate capacity within a specified degree of confidence. A major outcome of this work was development of a new workflow of simulation analysis, accommodating the addition of “random pseudo wells” to represent virtual characterization wells.

  7. INEEL Source Water Assessment

    SciTech Connect (OSTI)

    Sehlke, Gerald

    2003-03-01T23:59:59.000Z

    The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 mi2 and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL’s drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey’s Hydrological Unit scheme. Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency’s Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a thick vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL’s Source Water Assessment. Of the INEEL’s 12 public water systems, three systems rated as low susceptibility (EBR-I, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will protect the INEEL’s public water systems yet not too conservative to inhibit the INEEL from carrying out its missions.

  8. SYNCHROTRON RADIATION SOURCES

    SciTech Connect (OSTI)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01T23:59:59.000Z

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  9. Source rock maturation, San Juan sag

    SciTech Connect (OSTI)

    Gries, R.R.; Clayton, J.L.

    1989-09-01T23:59:59.000Z

    Kinetic modeling for thermal histories was simulated for seven wells in the San Juan sag honoring measured geochemical data. Wells in the area of Del Norte field (Sec. 9, T40N, R5E), where minor production has been established from an igneous sill reservoir, show that the Mancos Shale source rocks are in the mature oil generation window as a combined result of high regional heat flow and burial by approximately 2,700 m of Oligocene volcanic rocks. Maturation was relatively recent for this area and insignificant during Laramide subsidence. In the vicinity of Gramps field (Sec. 24, T33N, R2E) on the southwest flank of the San Juan sag, these same source rocks are exposed due to erosion of the volcanic cover but appear to have undergone a similar maturation history. At the north and south margins of the sag, two wells (Champlin 34A-13, Sec. 13, T35N, R4.5E; and Champlin 24A-1, Sec. 1, T44N, R5E) were analyzed and revealed that although the regional heat flow was probably similar to other wells, the depth of burial was insufficient to cause maturation (except where intruded by thick igneous sills that caused localized maturation). The Meridian Oil 23-17 South Fork well (Sec. 17, T39N, R4E) was drilled in a deeper part of the San Juan sag, and source rocks were intruded by numerous igneous sills creating a complex maturation history that includes overmature rocks in the lowermost Mancos Shale, possible CO{sub 2} generation from the calcareous Niobrara Member of the Mancos Shale, and mature source rocks in the upper Mancos Shale.

  10. TESTING TRIGGERED STAR FORMATION IN SIX H II REGIONS

    SciTech Connect (OSTI)

    Dirienzo, William J.; Indebetouw, Remy [Department of Astronomy, University of Virginia, P.O. Box 3818, Charlottesville, VA 22903 (United States); Brogan, Crystal; Friesen, Rachel K. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Cyganowski, Claudia J. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Churchwell, Ed, E-mail: dirienzo@virginia.edu [Department of Astronomy, University of Wisconsin-Madison, 475 N Charter Street, Madison, WI 53706 (United States)

    2012-12-01T23:59:59.000Z

    We investigated six H II regions with infrared, bright rimmed bubble or cometary morphology, in search of quantitative evidence for triggered star formation, both collect and collapse and radiatively driven implosion (RDI). We identified and classified 458 young stellar objects (YSOs) in and around the H II regions. YSOs were determined by fitting a collection of radiative transfer model spectral energy distributions to infrared photometry for a large sample of point sources. We determined areas where there exist enhanced populations of relatively unevolved YSOs on the bright rims of these regions, suggesting that star formation has been triggered there. We further investigated the physical properties of the regions by using radio continuum emission as a proxy for ionizing flux powering the H II regions, and {sup 13}CO (1-0) observations to measure masses and gravitational stability of molecular clumps. We used an analytical model of collect and collapse triggered star formation, as well as a simulation of RDI, and thus we compare the observed properties of the molecular gas with those predicted in the triggering scenarios. Notably, those regions in our sample that show evidence of cometary, or 'blister', morphology are more likely to show evidence of triggering.

  11. Regional long-term production modeling from a single well test, Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope

    SciTech Connect (OSTI)

    Anderson, Brian; Kurihara, Masanori; White, Mark D.; Moridis, George J.; Wilson, Scott J.; Pooladi-Darvish, Mehran; Gaddipati, Manohar; Masuda, Yoshihiro; Collett, T. S.; Hunter, Robert B.; Narita, Hideo; Rose, Kelly K.; Boswell, Ray

    2011-02-02T23:59:59.000Z

    Following the results from the open-hole formation pressure response test in the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well (Mount Elbert well) using Schlumberger’s Modular Dynamics Formation Tester (MDT) wireline tool, the International Methane Hydrate Reservoir Simulator Code Comparison project performed long-term reservoir simulations on three different model reservoirs. These descriptions were based on 1) the Mount Elbert gas hydrate accumulation as delineated by an extensive history-matching exercise, 2) an estimation of the hydrate accumulation near the Prudhoe Bay L-pad, and 3) a reservoir that would be down-dip of the Prudhoe Bay L-pad and therefore warmer and deeper. All of these simulations were based, in part, on the results of the MDT results from the Mount Elbert Well. The comparison group’s consensus value for the initial perme- ability of the hydrate-filled reservoir (k = 0.12 mD) and the permeability model based on the MDT history match were used as the basis for subsequent simulations on the three regional scenarios. The simulation results of the five different simulation codes, CMG STARS, HydrateResSim, MH-21 HYDRES, STOMP-HYD, and TOUGHþHYDRATE exhibit good qualitative agreement and the variability of potential methane production rates from gas hydrate reservoirs is illustrated. As expected, the pre- dicted methane production rate increased with increasing in situ reservoir temperature; however, a significant delay in the onset of rapid hydrate dissociation is observed for a cold, homogeneous reservoir and it is found to be repeatable. The inclusion of reservoir heterogeneity in the description of this cold reservoir is shown to eliminate this delayed production. Overall, simulations utilized detailed information collected across the Mount Elbert reservoir either obtained or determined from geophysical well logs, including thickness (37 ft), porosity (35%), hydrate saturation (65%), intrinsic permeability (1000 mD), pore water salinity (5 ppt), and formation temperature (3.3–3.9 ?C). This paper presents the approach and results of extrapolating regional forward production modeling from history-matching efforts on the results from a single well test.

  12. HIGH RESOLUTION FORWARD AND INVERSE EARTHQUAKE MODELING ON TERASCALE COMPUTERS

    E-Print Network [OSTI]

    Shewchuk, Jonathan

    highly populated seismic region in the U.S., it has well- characterized geological structures (including in characterizing earthquake source and basin material properties, a critical remaining challenge is to invert basin geology and earthquake sources, and to use this capability to model and forecast strong ground

  13. Regional Portfolio Model Redevelopment Update

    E-Print Network [OSTI]

    and Lost Opportunity Conservation 4. CO2 emission tracking 5. Dispatch of existing and new resources 6 futures) 11©2012 Navigant Consulting, Inc. E N E R G Y ­ Equilibrium electricity prices over time (able

  14. Source Term Modeling for Evaluating the Potential Impacts to Groundwater of Fluids Escaping from a Depleted Oil Reservoir Used for Carbon Sequestration

    SciTech Connect (OSTI)

    Cantrell, Kirk J.; Brown, Christopher F.

    2014-06-13T23:59:59.000Z

    In recent years depleted oil reservoirs have received special interest as carbon storage reservoirs because of their potential to offset costs through collaboration with enhanced oil recovery projects. Modeling is currently being conducted to evaluate potential risks to groundwater associated with leakage of fluids from depleted oil reservoirs used for storage of CO2. Modeling results reported here focused on understanding how toxic organic compounds found in oil will distribute between the various phases within a storage reservoir after introduction of CO2, understanding the migration potential of these compounds, and assessing potential groundwater impacts should leakage occur. Two model scenarios were conducted to evaluate how organic components in oil will distribute among the phases of interest (oil, CO2, and brine). The first case consisted of 50 wt.% oil and 50 wt.% water; the second case was 90 wt.% CO2 and 10 wt.% oil. Several key organic compounds were selected for special attention in this study based upon their occurrence in oil at significant concentrations, relative toxicity, or because they can serve as surrogate compounds for other more highly toxic compounds for which required input data are not available. The organic contaminants of interest (COI) selected for this study were benzene, toluene, naphthalene, phenanthrene, and anthracene. Partitioning of organic compounds between crude oil and supercritical CO2 was modeled using the Peng-Robinson equation of state over temperature and pressure conditions that represent the entire subsurface system (from those relevant to deep geologic carbon storage environments to near surface conditions). Results indicate that for a typical set of oil reservoir conditions (75°C, and 21,520 kPa) negligible amounts of the COI dissolve into the aqueous phase. When CO2 is introduced into the reservoir such that the final composition of the reservoir is 90 wt.% CO2 and 10 wt.% oil, a significant fraction of the oil dissolves into the vapor phase. As the vapor phase moves up through the stratigraphic column, pressures and temperatures decrease, resulting in significant condensation of oil components. The heaviest organic components condense early in this process (at higher pressures and temperatures), while the lighter components tend to remain in the vapor phase until much lower pressures and temperatures are reached. Based on the model assumptions, the final concentrations of COI to reach an aquifer at 1,520 kPa and 25°C were quite significant for benzene and toluene, whereas the concentrations of polynuclear aromatic hydrocarbons that reach the aquifer were very small. This work demonstrates a methodology that can provide COI source term concentrations in CO2 leaking from a reservoir and entering an overlying aquifer for use in risk assessments.

  15. african region summary: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    model (MRCM) in simulating the West African monsoon. The MRCM is built on the Regional Climate Model, ... Im, Eun-Soon 12 Regional Summary Gulf of Mexico Region Management...

  16. Characterization of ambient particulate matter in the Paso del Norte region

    SciTech Connect (OSTI)

    Li, W.W.; Currey, R.M.; Valenzuela, V.H.; Meuzelaar, H.L.C.; Sheya, S.A.; Anderson, J.R.; Banerjee, S.; Griffin, J.B.

    1999-07-01T23:59:59.000Z

    Air pollution in the Paso del Norte region, where West Texas abuts the southern boundary of New Mexico and the northern boundary of Chihuahua, Mexico is a common concern to the residents on both sides of the border. Parts of the region fail to meet the US and Mexican Ambient Air Quality Standards for particulate matter, ozone, and carbon monoxide. The regional air pollution problem is complicated due to arid climate, complex terrain topography, frequently occurring temperature inversions, extensive unpaved urban areas, an aging and poorly maintained vehicle fleet, and a number of other uncontrolled anthropogenic emission sources. The issue is further complicated by concerns arising from recent scientific evidence of the health effects associated with exposures to fine particulate matter. A study designed to address particulate matter (PM) air pollution problems in the region is currently undertaken by researchers from member universities of the Southwest Center for Environmental Research and Policy and several governmental agencies. The study attempts to (1) characterize the fine fraction of PM; (2) identify and characterize the major regional emission sources; (3) apportion the fine fraction of PM to the source emissions; and (4) establish a regional technological information clearinghouse. The short-term goal of this research is to initiate a research program to characterize, identify, and quantify the sources and nature of the PM in the region. The long-term goal of this study is to establish regional research capabilities to continue air quality monitoring, evaluation, modeling, and control after the implementation of the study. A scoping study to collect regional PM was conducted in December 1998.

  17. Localized Galactic sources and their contribution beyond the second knee

    E-Print Network [OSTI]

    De Donato, Cinzia

    2009-01-01T23:59:59.000Z

    The energy range encompassing the ankle of the cosmic ray energy spectrum probably marks the exhaustion of the accelerating sources in our Galaxy, as well as the end of the Galactic confinement. Furthermore, this is the region where the extragalactic flux penetrates the interstellar medium and starts, progressively, to be dominant. Although at lower energies it is likely that an "average" population of supernova remnants can be defined to account for most of the cosmic ray flux, this assumption is increasingly difficult to maintain as higher energies are considered. One possibility is that supernovas are still a main contributor along the first branch of the ankle region, but that the acceleration is now coming from well localized regions with a characteristic interstellar medium, or a sub-population of supernovas exploding in a peculiar circumstellar environment. These possibilities are analyzed in the present work using a two-dimensional diffusion model for cosmic ray propagation. Special emphasis is given ...

  18. REGIONAL WATER SUPPLY PLANNING AND

    E-Print Network [OSTI]

    Mays, Larry W.

    CHAPTER 3 REGIONAL WATER SUPPLY PLANNING AND CAPACITY EXPANSION MODELS Messele Z. Ejeta California Department of Water Resources Sacramento, California Larry W. Mays Department of Civil and Environmental Engineering Arizona State University Tempe, Arizona 3.1 INTRODUCTION Water supply planning on a regional scale

  19. Rigidity of a spherical capsule switches the localization of encapsulated particles between inner and peripheral regions under crowding condition: Simple model on cellular architecture

    SciTech Connect (OSTI)

    Shew, Chwen-Yang, E-mail: chwenyang.shew@csi.cuny.edu; Kondo, Kenta [Department of Chemistry, College of Staten Island, City University of New York, 2800 Victory Boulevard, Staten Island, New York 10314 (United States)] [Department of Chemistry, College of Staten Island, City University of New York, 2800 Victory Boulevard, Staten Island, New York 10314 (United States); Yoshikawa, Kenichi [Faculty of Life and Medical Sciences, Doshisha University, Kyoto 610-0394 (Japan)] [Faculty of Life and Medical Sciences, Doshisha University, Kyoto 610-0394 (Japan)

    2014-01-14T23:59:59.000Z

    We have investigated the inhomogeneous interior of confined spherical cavities as capsules containing encapsulated binary hard sphere mixtures for different compositions and cavity wall rigidity. Such a greatly simplified model manifests the effects of macromolecular crowding arising from excluded volume interactions in a tiny cell or a cellular nucleus. By fixing the number of large particles, the level of crowding is adjusted by changing the amount of small hard spheres in the cavity. For a rigid cavity, large spheres tend to pack in liquid-like order apart from the surface to the center of the cavity as the crowding level is increased. Whereas, for a soft cavity, larger spheres tend to blend with small spheres in the peripheral region at near the boundary of the cavity, and are susceptible to be depleted from the interior of the cavity as the cavity becomes more crowded. These results may help future elucidation of the thermodynamic pathways to stabilize the inhomogeneous structure of mixtures confined in cavities, such as the derepression of genome materials around the interior rim of the nucleus in a cancerous cell.

  20. Regional transport and dilution during high-pollution episodes in southern France: Summary of findings from the Field

    E-Print Network [OSTI]

    Ribes, Aurélien

    suburbs (oil plants in the Fos-Berre area) are major pollutant sources that cause frequent and hazardousRegional transport and dilution during high-pollution episodes in southern France: Summary of findings from the Field Experiment to Constraint Models of Atmospheric Pollution and Emissions Transport

  1. Microgrid Policy Review of Selected Major Countries, Regions, and Organizations

    E-Print Network [OSTI]

    Qu, Min

    2014-01-01T23:59:59.000Z

    4.IRED (Integration of Renewable Energy Sources and1.Regional Power Grid with renewable Energy Resourcespdf 2. Spanish Renewable Energy Review http://www.erec.org/

  2. FINAL Western Area Power Administration Desert Southwest Region...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    source materials in Western's DSW region archives and records and at the Arizona State University Library in Phoenix, Arizona. Information concerning the general history of...

  3. Western Area Power Administration, Desert Southwest Region Parker...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    areas, and other water sources that are vital in a region); and X (vii) Tundra, coral reefs, or rain forests.; or X (5) Involve genetically engineered organisms, synthetic...

  4. Quantifying the Difference Between the Flux-Tube Expansion Factor at the Source Surface and at the Alfv\\'en Surface Using A Global MHD Model for the Solar Wind

    E-Print Network [OSTI]

    Cohen, Ofer

    2015-01-01T23:59:59.000Z

    The potential field approximation has been providing a fast, and computationally inexpensive estimation for the solar corona's global magnetic field geometry for several decades. In contrast, more physics-based global magnetohydrodynamic (MHD) models have been used for a similar purpose, while being much more computationally expensive. Here, we investigate the difference in the field geometry between a global MHD model and the potential field source surface model (PFSSM) by tracing individual magnetic field lines in the MHD model from the Alfven surface (AS), through the source surface (SS), all the way to the field line footpoint, and then back to the source surface in the PFSSM. We also compare the flux-tube expansion at two points at the SS and the AS along the same radial line. We study the effect of solar cycle variations, the order of the potential field harmonic expansion, and different magnetogram sources. We find that the flux-tube expansion factor is consistently smaller at the AS than at the SS for...

  5. Radiation source with shaped emission

    DOE Patents [OSTI]

    Kubiak, Glenn D.; Sweatt, William C.

    2003-05-13T23:59:59.000Z

    Employing a source of radiation, such as an electric discharge source, that is equipped with a capillary region configured into some predetermined shape, such as an arc or slit, can significantly improve the amount of flux delivered to the lithographic wafers while maintaining high efficiency. The source is particularly suited for photolithography systems that employs a ringfield camera. The invention permits the condenser which delivers critical illumination to the reticle to be simplified from five or more reflective elements to a total of three or four reflective elements thereby increasing condenser efficiency. It maximizes the flux delivered and maintains a high coupling efficiency. This architecture couples EUV radiation from the discharge source into a ring field lithography camera.

  6. Ground Truth, Magnitude Calibration and Regional Phase Propagation and Detection in the Middle East and Horn of Africa

    SciTech Connect (OSTI)

    Nyblade, A; Brazier, R; Adams, A; Park, Y; Rodgers, A; Al-Amri, A

    2007-07-08T23:59:59.000Z

    In this project, we are exploiting several seismic data sets to improve U.S. operational capabilities to monitor for low yield nuclear tests across the Middle East (including the Iranian Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part of the East African Rift, Afar Depression, southern Red Sea and Gulf of Aden). The data sets are being used to perform three related tasks. (1) We are determining moment tensors, moment magnitudes and source depths for regional events in the magnitude 3.0 to 6.0 range. (2) These events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds, especially from events in Iran recorded at stations across the Arabian Peninsula. (3) We are collecting location ground truth at GT5 (local) and GT20 (regional) levels for seismic events with M > 2.5, including source geometry information and source depths. Towards meeting these objectives, seismograms from earthquakes in the Zagros Mountains recorded at regional distances have been inverted for moment tensors, which have then been used to create synthetic seismograms to determine the source depths of the earthquakes via waveform matching. The source depths have been confirmed by modeling teleseismic depth phases recorded on GSN and IMS stations. Early studies of the distribution of seismicity in the Zagros region found evidence for earthquakes in the upper mantle. But subsequent relocations of teleseismic earthquakes suggest that source depths are generally much shallower, lying mainly within the upper crust. All of the regional events studied so far nucleated within the upper crust, and most of the events have thrust mechanisms. The source mechanisms for these events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds for broadband seismic stations in the Arabian Peninsula, including IMS stations and stations belonging to the Saudi Arabian National Digital Seismic Network. To improve event locations, source mechanisms and attenuation estimates, new regional P and S wave velocity models of the upper mantle under the Arabian Peninsula have also been developed using data from teleseismic events recorded at stations within the Arabian Peninsula and Horn of Africa. These models show slower-than-average velocities within the lithospheric mantle under the entire Arabian Shield. However, at sublithospheric mantle depths, the low velocity region appears to be localized beneath the western side of the Arabian Shield.

  7. agricultural nonpoint source: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Carbon sequestration 1. Introduction Management of agricultural soils affects many inventories of potential non-point pollution source areas and regions with high carbon...

  8. Relationship of regional water quality to aquifer thermal energy storage

    SciTech Connect (OSTI)

    Allen, R.D.

    1983-11-01T23:59:59.000Z

    Ground-water quality and associated geologic characteristics may affect the feasibility of aquifer thermal energy storage (ATES) system development in any hydrologic region. This study sought to determine the relationship between ground-water quality parameters and the regional potential for ATES system development. Information was collected from available literature to identify chemical and physical mechanisms that could adversely affect an ATES system. Appropriate beneficiation techniques to counter these potential geochemical and lithologic problems were also identified through the literature search. Regional hydrology summaries and other sources were used in reviewing aquifers of 19 drainage regions in the US to determine generic geochemical characteristics for analysis. Numerical modeling techniques were used to perform geochemical analyses of water quality from 67 selected aquifers. Candidate water resources regions were then identified for exploration and development of ATES. This study identified six principal mechanisms by which ATES reservoir permeability may be impaired: (1) particulate plugging, (2) chemical precipitation, (3) liquid-solid reactions, (4) formation disaggregation, (5) oxidation reactions, and (6) biological activity. Specific proven countermeasures to reduce or eliminate these effects were found. Of the hydrologic regions reviewed, 10 were identified as having the characteristics necessary for ATES development: (1) Mid-Atlantic, (2) South-Atlantic Gulf, (3) Ohio, (4) Upper Mississippi, (5) Lower Mississippi, (6) Souris-Red-Rainy, (7) Missouri Basin, (8) Arkansas-White-Red, (9) Texas-Gulf, and (10) California.

  9. Problems with packaged sources in foreign countries

    SciTech Connect (OSTI)

    Abeyta, Cristy L [Los Alamos National Laboratory; Matzke, James L [Los Alamos National Laboratory; Zarling, John [Los Alamos National Laboratory; Tompkin, J. Andrew [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    The Global Threat Reduction Initiative's (GTRI) Off-Site Source Recovery Project (OSRP), which is administered by the Los Alamos National Laboratory (LANL), removes excess, unwanted, abandoned, or orphan radioactive sealed sources that pose a potential threat to national security, public health, and safety. In total, GTRI/OSRP has been able to recover more than 25,000 excess and unwanted sealed sources from over 825 sites. In addition to transuranic sources, the GTRI/OSRP mission now includes recovery of beta/gamma emitting sources, which are of concern to both the U.S. government and the International Atomic Energy Agency (IAEA). This paper provides a synopsis of cooperative efforts in foreign countries to remove excess and unwanted sealed sources by discussing three topical areas: (1) The Regional Partnership with the International Atomic Energy Agency; (2) Challenges in repatriating sealed sources; and (3) Options for repatriating sealed sources.

  10. DOE & Strategic Sourcing "New Challenges, New Opportunities"

    Broader source: Energy.gov (indexed) [DOE]

    & Strategic Sourcing "New Challenges, New Opportunities" What is it? NNSA Model DOE Future Activities Bill Marks, Commodity Manager, NNSA Supply Chain Management Center Gary...

  11. Role of positive ions on the surface production of negative ions in a fusion plasma reactor type negative ion source—Insights from a three dimensional particle-in-cell Monte Carlo collisions model

    SciTech Connect (OSTI)

    Fubiani, G.; Boeuf, J. P. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France) [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

    2013-11-15T23:59:59.000Z

    Results from a 3D self-consistent Particle-In-Cell Monte Carlo Collisions (PIC MCC) model of a high power fusion-type negative ion source are presented for the first time. The model is used to calculate the plasma characteristics of the ITER prototype BATMAN ion source developed in Garching. Special emphasis is put on the production of negative ions on the plasma grid surface. The question of the relative roles of the impact of neutral hydrogen atoms and positive ions on the cesiated grid surface has attracted much attention recently and the 3D PIC MCC model is used to address this question. The results show that the production of negative ions by positive ion impact on the plasma grid is small with respect to the production by atomic hydrogen or deuterium bombardment (less than 10%)

  12. Regional Summary Pacific Region Management Context

    E-Print Network [OSTI]

    , for the Eastern Pacific Ocean, and the Western and Central Pacific Fishery Commission, for the Western PacificRegional Summary Pacific Region Management Context The Pacific Region includes California, Oregon, and Washington. Federal fisheries in this region are managed by the Pacific Fishery Management Council (PFMC

  13. Identifying Isotropic Events Using a Regional Moment Tensor Inversion

    SciTech Connect (OSTI)

    Ford, S R; Dreger, D S; Walter, W R

    2008-11-04T23:59:59.000Z

    We calculate the deviatoric and isotropic source components for 17 explosions at the Nevada Test Site, as well as 12 earthquakes and 3 collapses in the surrounding region of the western US, using a regional time-domain full waveform inversion for the complete moment tensor. The events separate into specific populations according to their deviation from a pure double-couple and ratio of isotropic to deviatoric energy. The separation allows for anomalous event identification and discrimination between explosions, earthquakes, and collapses. Confidence regions of the model parameters are estimated from the data misfit by assuming normally distributed parameter values. We investigate the sensitivity of the resolved parameters of an explosion to imperfect Earth models, inaccurate event depths, and data with low signal-to-noise ratio (SNR) assuming a reasonable azimuthal distribution of stations. In the band of interest (0.02-0.10 Hz) the source-type calculated from complete moment tensor inversion is insensitive to velocity models perturbations that cause less than a half-cycle shift (<5 sec) in arrival time error if shifting of the waveforms is allowed. The explosion source-type is insensitive to an incorrect depth assumption (for a true depth of 1 km), and the goodness-of-fit of the inversion result cannot be used to resolve the true depth of the explosion. Noise degrades the explosive character of the result, and a good fit and accurate result are obtained when the signal-to-noise ratio (SNR) is greater than 5. We assess the depth and frequency dependence upon the resolved explosive moment. As the depth decreases from 1 km to 200 m, the isotropic moment is no longer accurately resolved and is in error between 50-200%. However, even at the most shallow depth the resultant moment tensor is dominated by the explosive component when the data have a good SNR.

  14. Central and Eastern United States (CEUS) Seismic Source Characterization (SSC) for Nuclear Facilities Project

    SciTech Connect (OSTI)

    Kevin J. Coppersmith; Lawrence A. Salomone; Chris W. Fuller; Laura L. Glaser; Kathryn L. Hanson; Ross D. Hartleb; William R. Lettis; Scott C. Lindvall; Stephen M. McDuffie; Robin K. McGuire; Gerry L. Stirewalt; Gabriel R. Toro; Robert R. Youngs; David L. Slayter; Serkan B. Bozkurt; Randolph J. Cumbest; Valentina Montaldo Falero; Roseanne C. Perman' Allison M. Shumway; Frank H. Syms; Martitia (Tish) P. Tuttle [Tish

    2012-01-31T23:59:59.000Z

    This report describes a new seismic source characterization (SSC) model for the Central and Eastern United States (CEUS). It will replace the Seismic Hazard Methodology for the Central and Eastern United States, EPRI Report NP-4726 (July 1986) and the Seismic Hazard Characterization of 69 Nuclear Plant Sites East of the Rocky Mountains, Lawrence Livermore National Laboratory Model, (Bernreuter et al., 1989). The objective of the CEUS SSC Project is to develop a new seismic source model for the CEUS using a Senior Seismic Hazard Analysis Committee (SSHAC) Level 3 assessment process. The goal of the SSHAC process is to represent the center, body, and range of technically defensible interpretations of the available data, models, and methods. Input to a probabilistic seismic hazard analysis (PSHA) consists of both seismic source characterization and ground motion characterization. These two components are used to calculate probabilistic hazard results (or seismic hazard curves) at a particular site. This report provides a new seismic source model. Results and Findings The product of this report is a regional CEUS SSC model. This model includes consideration of an updated database, full assessment and incorporation of uncertainties, and the range of diverse technical interpretations from the larger technical community. The SSC model will be widely applicable to the entire CEUS, so this project uses a ground motion model that includes generic variations to allow for a range of representative site conditions (deep soil, shallow soil, hard rock). Hazard and sensitivity calculations were conducted at seven test sites representative of different CEUS hazard environments. Challenges and Objectives The regional CEUS SSC model will be of value to readers who are involved in PSHA work, and who wish to use an updated SSC model. This model is based on a comprehensive and traceable process, in accordance with SSHAC guidelines in NUREG/CR-6372, Recommendations for Probabilistic Seismic Hazard Analysis: Guidance on Uncertainty and Use of Experts. The model will be used to assess the present-day composite distribution for seismic sources along with their characterization in the CEUS and uncertainty. In addition, this model is in a form suitable for use in PSHA evaluations for regulatory activities, such as Early Site Permit (ESPs) and Combined Operating License Applications (COLAs). Applications, Values, and Use Development of a regional CEUS seismic source model will provide value to those who (1) have submitted an ESP or COLA for Nuclear Regulatory Commission (NRC) review before 2011; (2) will submit an ESP or COLA for NRC review after 2011; (3) must respond to safety issues resulting from NRC Generic Issue 199 (GI-199) for existing plants and (4) will prepare PSHAs to meet design and periodic review requirements for current and future nuclear facilities. This work replaces a previous study performed approximately 25 years ago. Since that study was completed, substantial work has been done to improve the understanding of seismic sources and their characterization in the CEUS. Thus, a new regional SSC model provides a consistent, stable basis for computing PSHA for a future time span. Use of a new SSC model reduces the risk of delays in new plant licensing due to more conservative interpretations in the existing and future literature. Perspective The purpose of this study, jointly sponsored by EPRI, the U.S. Department of Energy (DOE), and the NRC was to develop a new CEUS SSC model. The team assembled to accomplish this purpose was composed of distinguished subject matter experts from industry, government, and academia. The resulting model is unique, and because this project has solicited input from the present-day larger technical community, it is not likely that there will be a need for significant revision for a number of years. See also Sponsors Perspective for more details. The goal of this project was to implement the CEUS SSC work plan for developing a regional CEUS SSC model. The work plan, formulated by the project manager and a

  15. Two source emission behaviour of alpha fragments of projectile having energy around 1 GeV per nucleon

    E-Print Network [OSTI]

    V. Singh; M. K. Singh; Ramji Pathak

    2010-09-17T23:59:59.000Z

    The emission of projectile fragments alpha has been studied in ^{84}Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source. It has been noticed that the temperature of hot and cold regions are dependent on the projectile mass number.

  16. HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM

    E-Print Network [OSTI]

    HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM IN PENNSYLVANIA HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM date ­ November 23, 2004 · Contract end date ­ March 31, 2006 #12;Hydrogen Regional Infrastructure Program in Pennsylvania Hydrogen Regional Infrastructure Program in Pennsylvania · Objectives ­ Capture

  17. Sources and production of organic aerosol in Mexico City: insights from the combination of a chemical transport model (PMCAMx-2008) and measurements

    E-Print Network [OSTI]

    Tsimpidi, A. P.

    Urban areas are large sources of organic aerosols and their precursors. Nevertheless, the contributions of primary (POA) and secondary organic aerosol (SOA) to the observed particulate matter levels have been difficult to ...

  18. EXPLORING THE NATURE OF THE GALACTIC CENTER {gamma}-RAY SOURCE WITH THE CHERENKOV TELESCOPE ARRAY

    SciTech Connect (OSTI)

    Linden, Tim; Profumo, Stefano [Department of Physics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2012-11-20T23:59:59.000Z

    Observations from multiple {gamma}-ray telescopes have uncovered a high-energy {gamma}-ray source spatially coincident with the Galactic center. Recently, a compelling model for the broadband {gamma}-ray emission has been formulated, which posits that high-energy protons emanating from Sgr A* could produce {gamma}-rays through {pi}{sup 0} decays resulting from inelastic collisions with the traversed interstellar gas in the region. Models of the gas distribution in the Galactic center region imply that the resulting {gamma}-ray morphology would be observed as a point source with all current telescopes, but that the upcoming Cherenkov Telescope Array (CTA) may be able to detect an extended emission profile with an unmistakable morphology. Here, we critically evaluate this claim, employing a three-dimensional gas distribution model and a detailed Monte Carlo simulation, and using the anticipated effective area and angular resolution of CTA. We find that the impressive angular resolution of CTA will be key to test hadronic emission models conclusively against, for example, point source or dark matter annihilation scenarios. We comment on the relevance of this result for searches for dark matter annihilation in the Galactic center region.

  19. Climatological simulations of ozone and atmospheric aerosols in the Greater Cairo region

    SciTech Connect (OSTI)

    Steiner, A. L.; Tawfik, A. B.; Shalaby, A.; Zakey, A. S.; Abdel Wahab, M. M.; Salah, Z.; Solmon, F.; Sillman, S.; Zaveri, Rahul A.

    2014-04-16T23:59:59.000Z

    An integrated chemistry-climate model (RegCM4-CHEM) simulates present-day climate, ozone and tropospheric aerosols over Egypt with a focus on Greater Cairo (GC) region. The densley populated GC region is known for its severe air quality issues driven by high levels of anthropogenic pollution in conjuction with natural sources such as dust and agricultural burning events. We find that current global emission inventories underestimate key pollutants such as nitrogen oxides and anthropogenic aerosol species. In the GC region, average-ground-based NO2 observations of 40-60 ppb are substantially higher than modeled estimates (5-10 ppb), likely due to model grid resolution, improper boundary layer representation, and poor emissions inventories. Observed ozone concentrations range from 35 ppb (winter) to 80 ppb (summer). The model reproduces the seasonal cycle fairly well, but modeled summer ozone is understimated by approximately 15 ppb and exhibits little interannual variability. For aerosols, springtime dust events dominate the seasonal aerosol cycle. The chemistry-climate model captures the springtime peak aerosol optical depth (AOD) of 0.7-1 but is slightly greater than satellite-derived AOD. Observed AOD decreases in the summer and increases again in the fall due to agricultural burning events in the Nile Delta, yet the model underestimates this fall observed AOD peak, as standard emissions inventories underestimate this burning and the resulting aerosol emissions. Our comparison of modeled gas and particulate phase atmospheric chemistry in the GC region indicates that improved emissions inventories of mobile sources and other anthropogenic activities are needed to improve air quality simulations in this region.

  20. Discovery of TeV Gamma-Ray Emission from the Cygnus Region

    SciTech Connect (OSTI)

    Abdo, A.A.; Allen, B.; Berley, D.; Blaufuss, E.; Casanova, S.; Chen, C.; Coyne, D.G.; Delay, R.S.; Dingus, B.L.; Ellsworth, R.W.; Fleysher, L.; Fleysher, R.; Gonzalez,; Goodman, J.A.; Hays, E.; Hoffman, C.M.; Kolterman, B.E.; Kelley, L.A.; Lansdell, C.P.; Linnemann, J.T.; McEnery, J.E.

    2006-11-28T23:59:59.000Z

    The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at {approx}12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray production and propagation. This observation indicates the existence of either hard-spectrum cosmic-ray sources and/or other sources of TeV gamma rays in the region.

  1. Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy

    E-Print Network [OSTI]

    A. A. Abdo; B. Allen; D. Berley; E. Blaufuss; S. Casanova; C. Chen; D. G. Coyne; R. S. Delay; B. L. Dingus; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzalez; J. A. Goodman; E. Hays; C. M. Hoffman; B. E. Kolterman; L. A. Kelley; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; I. V. Moskalenko; P. Nemethy; D. Noyes; J. M. Ryan; F. W. Samuelson; P. M. Saz Parkinson; M. Schneider; A. Shoup; G. Sinnis; A. J. Smith; A. W. Strong; G. W. Sullivan; V. Vasileiou; G. P. Walker; D. A. Williams; X. W. Xu; G. B. Yodh

    2006-11-21T23:59:59.000Z

    The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at ~12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray production and propagation. This observation indicates the existence of either hard-spectrum cosmic-ray sources and/or other sources of TeV gamma rays in the region.

  2. Figure 9. Conceptual model for regionally divergent responses of the air-land fluxes to CO2 fertilization, which increases the water-use efficiency of photosynthesis. In dry regions where

    E-Print Network [OSTI]

    Krakauer, Nir Y.

    parameterizations of these processes in models of Mediterranean- climate lands and obtaining a baseline for assessing changes. Acknowledgments NYK is supported by a NOAA Climate and Global Change postdoctoral.1 (2006). I. Y. Fung, S. C. Doney, K. Lindsay, J. John, Evolution of carbon sinks in a changing climate

  3. International Data on Radiological Sources

    SciTech Connect (OSTI)

    Martha Finck; Margaret Goldberg

    2010-07-01T23:59:59.000Z

    ABSTRACT The mission of radiological dispersal device (RDD) nuclear forensics is to identify the provenance of nuclear and radiological materials used in RDDs and to aid law enforcement in tracking nuclear materials and routes. The application of databases to radiological forensics is to match RDD source material to a source model in the database, provide guidance regarding a possible second device, and aid the FBI by providing a short list of manufacturers and distributors, and ultimately to the last legal owner of the source. The Argonne/Idaho National Laboratory RDD attribution database is a powerful technical tool in radiological forensics. The database (1267 unique vendors) includes all sealed sources and a device registered in the U.S., is complemented by data from the IAEA Catalogue, and is supported by rigorous in-lab characterization of selected sealed sources regarding physical form, radiochemical composition, and age-dating profiles. Close working relationships with global partners in the commercial sealed sources industry provide invaluable technical information and expertise in the development of signature profiles. These profiles are critical to the down-selection of potential candidates in either pre- or post- event RDD attribution. The down-selection process includes a match between an interdicted (or detonated) source and a model in the database linked to one or more manufacturers and distributors.

  4. Linear source approximation in CASMO5

    SciTech Connect (OSTI)

    Ferrer, R.; Rhodes, J. [Studsvik Scandpower, Inc., 504 Shoup Ave., Idaho Falls, ID 83402 (United States); Smith, K. [Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

    2012-07-01T23:59:59.000Z

    A Linear Source (LS) approximation has been implemented in the two-dimensional Method of Characteristics (MOC) transport solver in a prototype version of CASMO5. The LS approximation, which relies on the computation of trajectory-based spatial moments over source regions to obtain the linear source expansion coefficients, improves the solution accuracy relative to the 'flat' or constant source approximation. In addition, the LS formulation is capable of treating arbitrarily-shaped source regions and is compatible with standard Coarse-Mesh Finite Difference (CMFD) acceleration. Numerical tests presented in this paper for the C5G7 MOX benchmark show that, for comparable accuracy with respect to the reference solution, the LS approximation can reduce the run time by a factor of four and the memory requirements by a factor often relative to the FS scheme. (authors)

  5. Discovery of new X-ray sources near the unidentified gamma-ray source HESS J1841-055

    E-Print Network [OSTI]

    Nobukawa, K K; Tsuru, T G; Koyama, K

    2015-01-01T23:59:59.000Z

    HESS J1841$-$055 is a diffuse unidentified gamma-ray source with the size of $\\sim\\,1.3^{\\circ}\\times\\,1^{\\circ}$. No conclusive counterpart in other wavelengths has so far detected. To search for X-rays responsible for the TeV emission, the Suzaku observations were conducted, which covered a half region of the HESS source. In the soft band (0.5-2.0 keV), we discovered a diffuse emission, Suzaku J1840.2$-$0552, with the size of $\\sim10'$. Since its spectrum was fitted by an optically thin thermal plasma model, Suzaku J1840.2$-$0552 is likely to be a supernova remnant. We also discovered an extended source, Suzaku J1840.2$-$0544, in the hard band (2.0-8.0 keV) with an emission line at 6.1 keV. From the spectral feature and large interstellar absorption, this source is likely to be a cluster of galaxies behind the Galactic plane at the red-shift of $\\sim$0.09. The other diffuse source spatially overlaps with the SNR candidate G26.6$-$0.2, which shows a non-thermal dominant spectrum. Since no other candidate is ...

  6. Aspects of a high intensity neutron source

    E-Print Network [OSTI]

    Chapman, Peter H. (Peter Henry)

    2010-01-01T23:59:59.000Z

    A unique methodology for creating a neutron source model was developed for deuterons and protons incident on solid phase beryllium and lithium targets. This model was then validated against experimental results already ...

  7. Diffusion and Dispersion Characterization of a Numerical Tsunami Model

    E-Print Network [OSTI]

    Tolkova, Elena

    and numerical model. This plan is currently under devel- opment at the NCTR and a proof of concept has been-computed database of unit source solutions to determine the offshore tsunami waves. It then uses the MOST model (in nested grid mode) to propagate the offshore waves onshore for select regions. The critical factor

  8. Miniature x-ray source

    DOE Patents [OSTI]

    Trebes, James E. (Livermore, CA); Stone, Gary F. (Livermore, CA); Bell, Perry M. (Tracy, CA); Robinson, Ronald B. (Modesto, CA); Chornenky, Victor I. (Minnetonka, MN)

    2002-01-01T23:59:59.000Z

    A miniature x-ray source capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature x-ray source comprises a compact vacuum tube assembly containing a cathode, an anode, a high voltage feedthru for delivering high voltage to the anode, a getter for maintaining high vacuum, a connection for an initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is highly x-ray transparent and made, for example, from boron nitride. The compact size and potential for remote operation allows the x-ray source, for example, to be placed adjacent to a material sample undergoing analysis or in proximity to the region to be treated for medical applications.

  9. SLAM: a sodium-limestone concrete ablation model

    SciTech Connect (OSTI)

    Suo-Anttila, A.J.

    1983-12-01T23:59:59.000Z

    SLAM is a three-region model, containing a pool (sodium and reaction debris) region, a dry (boundary layer and dehydrated concrete) region, and a wet (hydrated concrete) region. The model includes a solution to the mass, momentum, and energy equations in each region. A chemical kinetics model is included to provide heat sources due to chemical reactions between the sodium and the concrete. Both isolated model as well as integrated whole code evaluations have been made with good results. The chemical kinetics and water migration models were evaluated separately, with good results. Several small and large-scale sodium limestone concrete experiments were simulated with reasonable agreement between SLAM and the experimental results. The SLAM code was applied to investigate the effects of mixing, pool temperature, pool depth and fluidization. All these phenomena were found to be of significance in the predicted response of the sodium concrete interaction. Pool fluidization is predicted to be the most important variable in large scale interactions.

  10. Infrared light sources with semimetal electron injection

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Biefeld, Robert M. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    An infrared light source is disclosed that comprises a layered semiconductor active region having a semimetal region and at least one quantum-well layer. The semimetal region, formed at an interface between a GaAsSb or GalnSb layer and an InAsSb layer, provides electrons and holes to the quantum-well layer to generate infrared light at a predetermined wavelength in the range of 2-6 .mu.m. Embodiments of the invention can be formed as electrically-activated light-emitting diodes (LEDs) or lasers, and as optically-pumped lasers. Since the active region is unipolar, multiple active regions can be stacked to form a broadband or multiple-wavelength infrared light source.

  11. Light curve of a source orbiting around a black hole: A fitting-formula

    E-Print Network [OSTI]

    V. Karas

    1996-05-15T23:59:59.000Z

    A simple, analytical fitting-formula for a photometric light curve of a source of light orbiting around a black hole is presented. The formula is applicable for sources on a circular orbit with radius smaller than 45 gravitational radii from the black hole. This range of radii requires gravitational focusation of light rays and the Doppler effect to be taken into account with care. The fitting-formula is therefore useful for modelling the X-ray variability of inner regions in active galactic nuclei.

  12. The prospects of usage of information data base at the Production Association Mayak as for modeling of the Ural region ecosystems

    SciTech Connect (OSTI)

    Mokrov, Y.G.; Drozhko, E.G.; Glagolenko, Y.V.; Smirnov, A.B. [Ministry of Atomic Energy of Russia, Chelyabinsk (Russian Federation). Production Association Mayak

    1993-12-31T23:59:59.000Z

    The environment has been contaminated in Russia as a result of the Production Association Mayak. The main source of contamination is considered to be gaseous and liquid radioactive wastes from production activities and from several accidents relating to the storage of liquid radioactive wastes. Practically all environmental objects in the vicinity of plant were exposed to radioactive contamination.

  13. DEVELOPMENT OF NEW MID-INFRARED ULTRAFAST LASER SOURCES FOR COMPACT COHERENT X-RAY SOURCES

    SciTech Connect (OSTI)

    Sterling Backus

    2012-05-14T23:59:59.000Z

    In this project, we proposed to develop laser based mid-infrared lasers as a potentially robust and reliable source of ultrafast pulses in the mid-infrared region of the spectrum, and to apply this light source to generating bright, coherent, femtosecond-to-attosecond x-ray beams.

  14. Clusters of Extragalactic Ultra Compact HII Regions

    E-Print Network [OSTI]

    Kelsey E. Johnson; Chip Kobulnicky; Phil Massey; Peter Conti

    2001-07-10T23:59:59.000Z

    We report on the detection of optically thick free-free radio sources in the galaxies M33, NGC 253, and NGC 6946 using data in the literature. We interpret these sources as being young, embedded star birth regions, which are likely to be clusters of ultracompact HII regions. All 35 of the sources presented in this article have positive radio spectral indices alpha>0 suggesting an optically thick thermal bremsstrahlung emission arising in the HII region surrounding hot stars. Energy requirements indicate a range of a several to >500 O7V star equivalents powering each HII region. Assuming a Salpeter IMF, this corresponds to integrated stellar masses of 0.1--60,000 Msun. For roughly half of the sources in our sample, there is no obvious optical counterpart, giving further support for their deeply embedded nature. Their luminosities and radio spectral energy distributions are consistent with HII regions having electron densities from 1500 cm^-3 to 15000 cm^-3 and radii of 1 - 7 pc. We suggest that the less luminous of these sources are extragalactic ultracompact HII region complexes, those of intermediate luminosity are similar to W49 in the Galaxy, while the brightest will be counterparts to 30 Doradus. These objects constitute the lower mass range of extragalactic ``ultradense HII regions'' which we argue are the youngest stages of massive star cluster formation yet observed. This sample is beginning to fill in the continuum of objects between small associations of ultracompact HII regions and the massive extragalactic clusters that may evolve into globular clusters.

  15. An alternative model for ultra-high pressure in the Svartberget Fe-Ti garnet-peridotite, Western Gneiss Region, Norway

    E-Print Network [OSTI]

    Andersen, Torgeir Bjørge

    Gneiss Region, Norway JOHANNES C. VRIJMOED1,*, YURI Y. PODLADCHIKOV1 , TORGEIR B. ANDERSEN1 and EBBE H, Norway *Corresponding author, e-mail: j.c.vrijmoed@fys.uio.no 2 Aker Exploration AS, PO Box 580, Sentrum, 4003 Stavanger, Norway Abstract: The previously reported ``Fe-Ti type'' garnet-peridotite is located

  16. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, N.; Ingersoll, D.

    1995-01-03T23:59:59.000Z

    Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

  17. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, Narayan (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

  18. Identifying isotropic events using a regional moment tensor inversion

    SciTech Connect (OSTI)

    Ford, S R; Dreger, D S; Walter, W R

    2008-07-16T23:59:59.000Z

    The deviatoric and isotropic source components for 17 explosions at the Nevada Test Site, as well as 12 earthquakes and 3 collapses in the surrounding region of the western US, are calculated using a regional time-domain full waveform inversion for the complete moment tensor. The events separate into specific populations according to their deviation from a pure double-couple and ratio of isotropic to deviatoric energy. The separation allows for anomalous event identification and discrimination between explosions, earthquakes, and collapses. Confidence regions of the model parameters are estimated from the data misfit by assuming normally distributed parameter values. We investigate the sensitivity of the resolved parameters of an explosion to imperfect Earth models, inaccurate event depths, and data with a low signal-to-noise ratio (SNR) assuming a reasonable azimuthal distribution of stations. In the band of interest (0.02-0.10 Hz) the source-type calculated from complete moment tensor inversion is insensitive to velocity models perturbations that cause less than a half-cycle shift (<5 sec) in arrival time error if shifting of the waveforms is allowed. The explosion source-type is insensitive to an incorrect depth assumption (for a true depth of 1 km), but the goodness-of-fit of the inversion result cannot be used to resolve the true depth of the explosion. Noise degrades the explosive character of the result, and a good fit and accurate result are obtained when the signal-to-noise ratio (SNR) is greater than 5. We assess the depth and frequency dependence upon the resolved explosive moment. As the depth decreases from 1 km to 200 m, the isotropic moment is no longer accurately resolved and is in error between 50-200%. However, even at the most shallow depth the resultant moment tensor is dominated by the explosive component when the data has a good SNR. The sensitivity investigation is extended via the introduction of the network sensitivity solution, which takes into account the unique station distribution, frequency band, and SNR of a given test scenario. An example of this analysis is presented for the North Korea test, which shows that in order to constrain the explosive component one needs a certain station configuration. In the future we will analyze the bias in the source-type parameters due to error in the Green's function by incorporating a suite of suitable velocity models in the inversion.

  19. Beta relaxation in the shear mechanics of equilibrium viscous liquids: Phenomenology and network modeling of the alpha-beta merging region

    E-Print Network [OSTI]

    Bo Jakobsen; Kristine Niss; Claudio Maggi; Niels Boye Olsen; Tage Christensen; Jeppe C. Dyre

    2010-05-26T23:59:59.000Z

    The phenomenology of the beta relaxation process in the shear-mechanical response of glass-forming liquids is summarized and compared to that of the dielectric beta process. Furthermore, we discuss how to model the observations by means of standard viscoelastic modeling elements. Necessary physical requirements to such a model are outlined, and it is argued that physically relevant models must be additive in the shear compliance of the alpha and beta parts. A model based on these considerations is proposed and fitted to data for Polyisobutylene 680.

  20. Northwest Regional Technology Center

    E-Print Network [OSTI]

    Northwest Regional Technology Center for Homeland Security The Northwest Regional Technology Center and deployment of technologies that are effective homeland security solutions for the region, and accelerate technology transfer to the national user community. Foster a collaborative spirit across agencies

  1. Evolution of laser-produced Sn extreme ultraviolet source diameter for high-brightness source

    SciTech Connect (OSTI)

    Roy, Amitava, E-mail: roy@fzu.cz, E-mail: aroy@barc.gov.in [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Utsunomiya, Tochigi 321-8585 (Japan); HiLASE Centre, Institute of Physics ASCR, v.v.i., Za Radnicí 828, 25241 Dolní B?ežany (Czech Republic); Arai, Goki; Hara, Hiroyuki; Higashiguchi, Takeshi, E-mail: higashi@cc.utsunomiya-u.ac.jp [Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), Utsunomiya University, Utsunomiya, Tochigi 321-8585 (Japan); Ohashi, Hayato [Graduate School of Science and Engineering for Research, University of Toyama, Toyama, Toyama 930-8555 (Japan); Sunahara, Atsushi [Institute for Laser Technology, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Li, Bowen [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Dunne, Padraig; O'Sullivan, Gerry [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Miura, Taisuke; Mocek, Tomas; Endo, Akira [HiLASE Centre, Institute of Physics ASCR, v.v.i., Za Radnicí 828, 25241 Dolní B?ežany (Czech Republic)

    2014-08-18T23:59:59.000Z

    We have investigated the effect of irradiation of solid Sn targets with laser pulses of sub-ns duration and sub-mJ energy on the diameter of the extreme ultraviolet (EUV) emitting region and source conversion efficiency. It was found that an in-band EUV source diameter as low as 18??m was produced due to the short scale length of a plasma produced by a sub-ns laser. Most of the EUV emission occurs in a narrow region with a plasma density close to the critical density value. Such EUV sources are suitable for high brightness and high repetition rate metrology applications.

  2. Chapter 2: Sources and Deposition of Trace Metals 2.1 Main Sources of Atmospheric Pollution...............................................7

    E-Print Network [OSTI]

    Short, Daniel

    5 Chapter 2: Sources and Deposition of Trace Metals 2.1 Main Sources of Atmospheric Pollution distances causing regional or global pollution. Fig. 2.1: Sources of trace metals in the environment. Contamination of the atmosphere by pollutant trace metals affects the environment directly through its impact

  3. A 3D finite-element modelling investigation into optimal survey parameters and direct imaging for marine controlled-source electromagnetic surveys

    E-Print Network [OSTI]

    Lau, Ryan

    2007-09-17T23:59:59.000Z

    frequency electromagnetic signal into the sea and downwards into the seabed. A transmitter is typically towed behind a ship to various offsets at which time an electromagnetic field is emitted from the dipole. The primary electromagnetic (EM) energy... possible direct hydrocarbon indicator for deep-sea prospects using EM energy: Oil & Gas Journal 100, 19, 30-38. MacGregor, L., and Sinha, M., 2000, Use of marine controlled-source electromagnetic sounding sub-basalt exploration: Geophysical...

  4. BROOKHAVEN NATIONAL Sealed Source

    E-Print Network [OSTI]

    Homes, Christopher C.

    BROOKHAVEN NATIONAL LABORATORY Sealed Source Contamination Incident October 13, 2011 #12;2 Cesium (Cs-137) Source Failure On September 28th @ ~1600 contamination event discovered · Two Radiological Contamination was from a Cs-137 (265 micro-curie) "sealed source" used to test area radiation monitors. · Source

  5. Underground Test Area Subproject Phase I Data Analysis Task. Volume V - Transport Parameter and Source Term Data Documentation Package

    SciTech Connect (OSTI)

    None

    1996-12-01T23:59:59.000Z

    Volume V of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the transport parameter and source term data. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

  6. A 4-D Climatology (1979-2009) of the Monthly Tropospheric Aerosol Optical Depth Distribution over the Mediterranean Region from a Comparative Evaluation and Blending of Remote Sensing and Model Products

    SciTech Connect (OSTI)

    Nabat, P.; Somot, S.; Mallet, M.; Chiapello, I.; Morcrette, J. -J.; Solmon, F.; Szopa, S.; Dulac, F.; Collins, W.; Ghan, Steven J.; Horowitz, L.; Lamarque, J.-F.; Lee, Y. H.; Naik, Vaishali; Nagashima, T.; Shindell, Drew; Skeie, R. B.

    2013-05-17T23:59:59.000Z

    Since the 1980s several spaceborne sensors have been used to retrieve the aerosol optical depth (AOD) over the Mediterranean region. In parallel, AOD climatologies coming from different numerical model simulations are now also available, permitting to distinguish the contribution of several aerosol types to the total AOD. In this work, we perform a comparative analysis of this unique multiyear database in terms of total AOD and of its apportionment by the five main aerosol types (soil dust, seasalt, sulfate, black and organic carbon). We use 9 different satellite-derived monthly AOD products: NOAA/AVHRR, SeaWiFS (2 products), TERRA/MISR, TERRA/MODIS, AQUA/MODIS, ENVISAT/MERIS, PARASOL/POLDER and MSG/SEVIRI, as well as 3 more historical datasets: NIMBUS7/CZCS, TOMS (onboard NIMBUS7 and Earth- Probe) and METEOSAT/MVIRI. Monthly model datasets include the aerosol climatology from Tegen et al. (1997), the climate-chemistry models LMDz-OR-INCA and RegCM-4, the multi-model mean coming from the ACCMIP exercise, and the reanalyses GEMS and MACC. Ground-based Level- 2 AERONET AOD observations from 47 stations around the basin are used here to evaluate the model and satellite data. The sensor MODIS (on AQUA and TERRA) has the best average AOD scores over this region, showing a relevant spatiotemporal variability and highlighting high dust loads over Northern Africa and the sea (spring and summer), and sulfate aerosols over continental Europe (summer). The comparison also shows limitations of certain datasets (especially MERIS and SeaWiFS standard products). Models reproduce the main patterns of the AOD variability over the basin. The MACC reanalysis is the closest to AERONET data, but appears to underestimate dust over Northern Africa, where RegCM-4 is found closer to MODIS thanks to its interactive scheme for dust emissions. The vertical dimension is also investigated using the CALIOP instrument. This study confirms differences of vertical distribution between dust aerosols showing a large vertical spread, and other continental and marine aerosols which are confined in the boundary layer. From this compilation, we propose a 4-D blended product from model and satellite data, consisting in monthly time series of 3-D aerosol distribution at a 50 km horizontal resolution over the Euro-Mediterranean marine and continental region for the 2003–2009 period. The product is based on the total AOD from AQUA/MODIS, apportioned into sulfates, black and organic carbon from the MACC reanalysis, and into dust and sea-salt aerosols from RegCM-4 simulations, which are distributed vertically based on CALIOP climatology.We extend the 2003–2009 reconstruction to the past up to 1979 using the 2003–2009 average and applying the decreasing trend in sulfate aerosols from LMDz-OR-INCA, whose AOD trends over Europe and the Mediterranean are median among the ACCMIP models. Finally optical properties of the different aerosol types in this region are proposed from Mie calculations so that this reconstruction can be included in regional climate models for aerosol radiative forcing and aerosolclimate studies.

  7. SOURCE PHENOMENOLOGY EXPERIMENTS IN ARIZONA

    SciTech Connect (OSTI)

    Jessie L. Bonner; Brian Stump; Mark Leidig; Heather Hooper; Xiaoning (David) Yang; Rongmao Zhou; Tae Sung Kim; William R. Walter; Aaron Velasco; Chris Hayward; Diane Baker; C. L. Edwards; Steven Harder; Travis Glenn; Cleat Zeiler; James Britton; James F. Lewkowicz

    2005-09-30T23:59:59.000Z

    The Arizona Source Phenomenology Experiments (SPE) have resulted in an important dataset for the nuclear monitoring community. The 19 dedicated single-fired explosions and multiple delay-fired mining explosions were recorded by one of the most densely instrumented accelerometer and seismometer arrays ever fielded, and the data have already proven useful in quantifying confinement and excitation effects for the sources. It is very interesting to note that we have observed differences in the phenomenology of these two series of explosions resulting from the differences between the relatively slow (limestone) and fast (granodiorite) media. We observed differences at the two SPE sites in the way the rock failed during the explosions, how the S-waves were generated, and the amplitude behavior as a function of confinement. Our consortium's goal is to use the synergy of the multiple datasets collected during this experiment to unravel the phenomenological differences between the two emplacement media. The data suggest that the main difference between single-fired chemical and delay-fired mining explosion seismograms at regional distances is the increased surface wave energy for the latter source type. The effect of the delay-firing is to decrease the high-frequency P-wave amplitudes while increasing the surface wave energy because of the longer source duration and spall components. The results suggest that the single-fired explosions are surrogates for nuclear explosions in higher frequency bands (e.g., 6-8 Hz Pg/Lg discriminants). We have shown that the SPE shots, together with the mining explosions, are efficient sources of S-wave energy, and our next research stage is to postulate the possible sources contributing to the shear-wave energy.

  8. Models for evaluation of energy technology and policy options to maximize low carbon source penetration in the United States energy supply.

    SciTech Connect (OSTI)

    Pickard, Paul S.; Kataoka, Dawn; Reno, Marissa Devan; Malczynski, Leonard A.; Peplinski, William J.; Roach, Jesse D.; Brainard, James Robert; West, Todd H.; Schoenwald, David Alan

    2009-12-01T23:59:59.000Z

    An initial version of a Systems Dynamics (SD) modeling framework was developed for the analysis of a broad range of energy technology and policy questions. The specific question selected to demonstrate this process was 'what would be the carbon and import implications of expanding nuclear electric capacity to provide power for plug in hybrid vehicles?' Fifteen SNL SD energy models were reviewed and the US Energy and Greenhouse gas model (USEGM) and the Global Nuclear Futures model (GEFM) were identified as the basis for an initial modeling framework. A basic U.S. Transportation model was created to model U.S. fleet changes. The results of the rapid adoption scenario result in almost 40% of light duty vehicles being PHEV by 2040 which requires about 37 GWy/y of additional electricity demand, equivalent to about 25 new 1.4 GWe nuclear plants. The adoption rate of PHEVs would likely be the controlling factor in achieving the associated reduction in carbon emissions and imports.

  9. Numerical analysis of atomic density distribution in arc driven negative ion sources

    SciTech Connect (OSTI)

    Yamamoto, T., E-mail: t.yamamoto@ppl.appi.keio.ac.jp; Shibata, T.; Hatayama, A. [Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522 (Japan)] [Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522 (Japan); Kashiwagi, M.; Hanada, M. [Japan Atomic Energy Agency (JAEA), 801-1 Mukouyama, Naka 311-0193 (Japan)] [Japan Atomic Energy Agency (JAEA), 801-1 Mukouyama, Naka 311-0193 (Japan); Sawada, K. [Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 (Japan)] [Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 (Japan)

    2014-02-15T23:59:59.000Z

    The purpose of this study is to calculate atomic (H{sup 0}) density distribution in JAEA 10 ampere negative ion source. A collisional radiative model is developed for the calculation of the H{sup 0} density distribution. The non-equilibrium feature of the electron energy distribution function (EEDF), which mainly determines the H{sup 0} production rate, is included by substituting the EEDF calculated from 3D electron transport analysis. In this paper, the H{sup 0} production rate, the ionization rate, and the density distribution in the source chamber are calculated. In the region where high energy electrons exist, the H{sup 0} production and the ionization are enhanced. The calculated H{sup 0} density distribution without the effect of the H{sup 0} transport is relatively small in the upper region. In the next step, the effect should be taken into account to obtain more realistic H{sup 0} distribution.

  10. Application of Spatial Data Modeling and Geographical Information Systems (GIS) for Identification of Potential Siting Options for Various Electrical Generation Sources

    SciTech Connect (OSTI)

    Mays, Gary T [ORNL; Belles, Randy [ORNL; Blevins, Brandon R [ORNL; Hadley, Stanton W [ORNL; Harrison, Thomas J [ORNL; Jochem, Warren C [ORNL; Neish, Bradley S [ORNL; Omitaomu, Olufemi A [ORNL; Rose, Amy N [ORNL

    2012-05-01T23:59:59.000Z

    Oak Ridge National Laboratory (ORNL) initiated an internal National Electric Generation Siting Study, which is an ongoing multiphase study addressing several key questions related to our national electrical energy supply. This effort has led to the development of a tool, OR-SAGE (Oak Ridge Siting Analysis for power Generation Expansion), to support siting evaluations. The objective in developing OR-SAGE was to use industry-accepted approaches and/or develop appropriate criteria for screening sites and employ an array of Geographic Information Systems (GIS) data sources at ORNL to identify candidate areas for a power generation technology application. The initial phase of the study examined nuclear power generation. These early nuclear phase results were shared with staff from the Electric Power Research Institute (EPRI), which formed the genesis and support for an expansion of the work to several other power generation forms, including advanced coal with carbon capture and storage (CCS), solar, and compressed air energy storage (CAES). Wind generation was not included in this scope of work for EPRI. The OR-SAGE tool is essentially a dynamic visualization database. The results shown in this report represent a single static set of results using a specific set of input parameters. In this case, the GIS input parameters were optimized to support an economic study conducted by EPRI. A single set of individual results should not be construed as an ultimate energy solution, since US energy policy is very complex. However, the strength of the OR-SAGE tool is that numerous alternative scenarios can be quickly generated to provide additional insight into electrical generation or other GIS-based applications. The screening process divides the contiguous United States into 100 x 100 m (1-hectare) squares (cells), applying successive power generation-appropriate site selection and evaluation criteria (SSEC) to each cell. There are just under 700 million cells representing the contiguous United States. If a cell meets the requirements of each criterion, the cell is deemed a candidate area for siting a specific power generation form relative to a reference plant for that power type. Some SSEC parameters preclude siting a power plant because of an environmental, regulatory, or land-use constraint. Other SSEC assist in identifying less favorable areas, such as proximity to hazardous operations. All of the selected SSEC tend to recommend against sites. The focus of the ORNL electrical generation source siting study is on identifying candidate areas from which potential sites might be selected, stopping short of performing any detailed site evaluations or comparisons. This approach is designed to quickly screen for and characterize candidate areas. Critical assumptions supporting this work include the supply of cooling water to thermoelectric power generation; a methodology to provide an adequate siting footprint for typical power plant applications; a methodology to estimate thermoelectric plant capacity while accounting for available cooling water; and a methodology to account for future ({approx}2035) siting limitations as population increases and demands on freshwater sources change. OR-SAGE algorithms were built to account for these critical assumptions. Stream flow is the primary thermoelectric plant cooling source evaluated in this study. All cooling was assumed to be provided by a closed-cycle cooling (CCC) system requiring makeup water to account for evaporation and blowdown. Limited evaluations of shoreline cooling and the use of municipal processed water (gray) cooling were performed. Using a representative set of SSEC as input to the OR-SAGE tool and employing the accompanying critical assumptions, independent results for the various power generation sources studied were calculated.

  11. Southeast Regional Carbon Sequestration Partnership

    SciTech Connect (OSTI)

    Kenneth J. Nemeth

    2006-08-30T23:59:59.000Z

    The Southeast Regional Carbon Sequestration Partnership's (SECARB) Phase I program focused on promoting the development of a framework and infrastructure necessary for the validation and commercial deployment of carbon sequestration technologies. The SECARB program, and its subsequent phases, directly support the Global Climate Change Initiative's goal of reducing greenhouse gas intensity by 18 percent by the year 2012. Work during the project's two-year period was conducted within a ''Task Responsibility Matrix''. The SECARB team was successful in accomplishing its tasks to define the geographic boundaries of the region; characterize the region; identify and address issues for technology deployment; develop public involvement and education mechanisms; identify the most promising capture, sequestration, and transport options; and prepare action plans for implementation and technology validation activity. Milestones accomplished during Phase I of the project are listed below: (1) Completed preliminary identification of geographic boundaries for the study (FY04, Quarter 1); (2) Completed initial inventory of major sources and sinks for the region (FY04, Quarter 2); (3) Completed initial development of plans for GIS (FY04, Quarter 3); (4) Completed preliminary action plan and assessment for overcoming public perception issues (FY04, Quarter 4); (5) Assessed safety, regulatory and permitting issues (FY05, Quarter 1); (6) Finalized inventory of major sources/sinks and refined GIS algorithms (FY05, Quarter 2); (7) Refined public involvement and education mechanisms in support of technology development options (FY05, Quarter 3); and (8) Identified the most promising capture, sequestration and transport options and prepared action plans (FY05, Quarter 4).

  12. Charge exchange molecular ion source

    DOE Patents [OSTI]

    Vella, Michael C.

    2003-06-03T23:59:59.000Z

    Ions, particularly molecular ions with multiple dopant nucleons per ion, are produced by charge exchange. An ion source contains a minimum of two regions separated by a physical barrier and utilizes charge exchange to enhance production of a desired ion species. The essential elements are a plasma chamber for production of ions of a first species, a physical separator, and a charge transfer chamber where ions of the first species from the plasma chamber undergo charge exchange or transfer with the reactant atom or molecules to produce ions of a second species. Molecular ions may be produced which are useful for ion implantation.

  13. Scenarios of Building Energy Demand for China with a Detailed Regional Representation

    SciTech Connect (OSTI)

    Yu, Sha; Eom, Jiyong; Zhou, Yuyu; Evans, Meredydd; Clarke, Leon E.

    2014-02-07T23:59:59.000Z

    Building energy consumption currently accounts for 28% of China’s total energy use and is expected to continue to grow induced by floorspace expansion, income growth, and population change. Fuel sources and building services are also evolving over time as well as across regions and building types. To understand sectoral and regional difference in building energy use and how socioeconomic, physical, and technological development influence the evolution of the Chinese building sector, this study developed a building energy use model for China downscaled into four climate regions under an integrated assessment framework. Three building types (rural residential, urban residential, and commercial) were modeled specifically in each climate region. Our study finds that the Cold and Hot Summer Cold Winter regions lead in total building energy use. The impact of climate change on heating energy use is more significant than that of cooling energy use in most climate regions. Both rural and urban households will experience fuel switch from fossil fuel to cleaner fuels. Commercial buildings will experience rapid growth in electrification and energy intensity. Improved understanding of Chinese buildings with climate change highlighted in this study will help policy makers develop targeted policies and prioritize building energy efficiency measures.

  14. Sources of stress gradients in electrodeposited Ni MEMS.

    SciTech Connect (OSTI)

    Hearne, Sean Joseph; Floro, Jerrold Anthony; Dyck, Christopher William

    2004-06-01T23:59:59.000Z

    The ability of future integrated metal-semiconductor micro-systems such as RF MEMS to perform highly complex functions will depend on developing freestanding metal structures that offer improved conductivity and reflectivity over polysilicon structures. For example, metal-based RF MEMS technology could replace the bulky RF system presently used in communications, navigation, and avionics systems. However, stress gradients that induce warpage of active components have prevented the implementation of this technology. Figure 1, is an interference micrograph image of a series of cantilever beams fabricated from electrodeposited Ni. The curvature in the beams was the result of stress gradients intrinsic to the electrodeposition process. To study the sources of the stress in electrodeposition of Ni we have incorporated a wafer curvature based stress sensor, the multibeam optical stress sensor, into an electrodeposition cell. We have determined that there are two regions of stress induced by electrodepositing Ni from a sulfamate-based bath (Fig 2). The stress evolution during the first region, 0-1000{angstrom}, was determined to be dependent only on the substrate material (Au vs. Cu), whereas the stress evolution during the second region, >1000{angstrom}, was highly dependent on the deposition conditions. In this region, the stress varied from +0.5 GPa to -0.5GPa, depending solely on the deposition rate. We examined four likely sources for the compressive intrinsic stress, i.e. reduction in tensile stress, and determined that only the adatom diffusion into grain boundaries model of Sheldon, et al. could account for the observed compressive stress. In the presentation, we shall discuss the compressive stress generation mechanisms considered and the ramifications of these results on fabrication of electrodeposited Ni for MEMS applications.

  15. Analysis of Saturn kilometric radiation near a source center J. D. Menietti,1

    E-Print Network [OSTI]

    Gurnett, Donald A.

    reported source region encounter and with similar observations at Earth auroral kilometric source regions is believed to be the cyclotron maser instability (CMI) [Wu and Lee, 1979]. The free energy source has more distribu- tions with energies in the range 1 to 10 keV [Delory et al., 1998; Su et al., 2007]. The CMI

  16. Evidence of Reactive Aromatics As a Major Source of Peroxy Acetyl Nitrate over China

    SciTech Connect (OSTI)

    Liu, Zhen; Wang, Yuhang; Gu, Dasa; Zhao, Chun; Huey, L. G.; Stickel, Robert; Liao, Jin; Shao, Min; Zhu, T.; Zeng, Limin; Liu, Shaw C.; Chang, Chih-Chung; Amoroso, Antonio; Costabile, Francesa

    2010-09-15T23:59:59.000Z

    We analyze the observations of near-surface peroxy acetyl nitrate (PAN) and its precursors in Beijing, China in August of 2007. The levels of PAN are remarkably high (up to 14 ppbv), surpassing those measured over other urban regions in recent years. Analyses employing a 1-D version of a chemical transport model (Regional chEmical and trAnsport Model, REAM) indicate that aromatic non-methane hydrocarbons (NMHCs) are the dominant (55-75%) PAN source. The major oxidation product of aromatics that produces acetyl peroxy radicals is methylglyoxal (MGLY). PAN and O3 in the observations are correlated at daytime; aromatic NMHCs appear to play an important role in O3 photochemistry. Previous NMHC measurements indicate the presence of reactive aromatics at high levels over broad polluted regions of China. Aromatics are often ignored in global and (to a lesser degree) regional 3D photochemical transport models; their emissions over China as well as photochemistry are quite uncertain.Our findings suggest that critical assessments of aromatics emissions and chemistry (such as the yields of MGLY) are necessary to understand and assess ozone photochemistry and regional pollution export in China.

  17. Aerosol Indirect Effect on the Grid-scale Clouds in the Two-way Coupled WRF-CMAQ: Model Description, Development, Evaluation and Regional Analysis

    SciTech Connect (OSTI)

    Yu, Shaocai; Mathur, Rohit; Pleim, Jonathan; Wong, David; Gilliam, R.; Alapaty, Kiran; Zhao, Chun; Liu, Xiaohong

    2014-10-24T23:59:59.000Z

    This study implemented first, second and glaciations aerosol indirect effects (AIE) on resolved clouds in the two-way coupled WRF-CMAQ modeling system by including parameterizations for both cloud drop and ice number concentrations on the basis of CMAQpredicted aerosol distributions and WRF meteorological conditions. The performance of the newly-developed WRF-CMAQ model, with alternate CAM and RRTMG radiation schemes, was evaluated with the observations from the CERES satellite and surface monitoring networks (AQS, IMPROVE, CASTNet, STN, and PRISM) over the continental U.S. (CONUS) (12-km resolution) and eastern Texas (4-km resolution) during August and September of 2006. The results at the AQS surface sites show that in August, the NMB values for PM2.5 over the eastern/western U.S (EUS/WUS) and western U.S. (WUS) are 5.3% (?0.1%) and 0.4% (-5.2%) for WRF-CMAQ/CAM (WRF-CMAQ/RRTMG), respectively. The evaluation of PM2.5 chemical composition reveals that in August, WRF-CMAQ/CAM (WRF-CMAQ/RRTMG) consistently underestimated the observed SO4 2? by -23.0% (-27.7%), -12.5% (-18.9%) and -7.9% (-14.8%) over the EUS at the CASTNet, IMPROVE and STN sites, respectively. Both models (WRF-CMAQ/CAM, WRF-CMAQ/RRTMG) overestimated the observed mean OC, EC and TC concentrations over the EUS in August at the IMPROVE sites. Both models generally underestimated the cloud field (SWCF) over the CONUS in August due to the fact that the AIE on the subgrid convective clouds was not considered when the model simulations were run at the 12 km resolution. This is in agreement with the fact that both models captured SWCF and LWCF very well for the 4-km simulation over the eastern Texas when all clouds were resolved by the finer domain. Both models generally overestimated the observed precipitation by more than 40% mainly because of significant overestimation in the southern part of the CONUS in August. The simulations of WRF-CMAQ/CAM and WRF-CMAQ/RRTMG show dramatic improvements for SWCF, LWCF, COD, cloud fractions and precipitation over the ocean relative to those of WRF default cases in August. The model performance in September is similar to that in August except for greater overestimation of PM2.5 due to the overestimations of SO4 2-, NH4 +, NO3 -, and TC over the EUS, less underestimation of clouds (SWCF) over the land areas due to about 10% lower SWCF values and less convective clouds in September.

  18. Reprinted in A S-T X from JOURNAL OF GEOPHYSICAL RESEARCHM E A fully nonlinear regional wave model for the Bight of

    E-Print Network [OSTI]

    Snyder, Russell L.

    of Abaco, Bahamas. It discusses this model's hybrid representation for nonlinear transfer and the numerical of the nonlinear-transfer computa- tion, and extends the hybrid representation to various #12;nite depths characteristic of the Abaco Bight. It also extends the previous discussion of truncations of the hybrid repre

  19. Sanders, J. E.; and Merguerian, Charles, 1995b, New York City region: Unique testing ground for flow models of Quaternary continental glaciers.

    E-Print Network [OSTI]

    Merguerian, Charles

    for flow models of Quaternary continental glaciers. The Mesozoic red-bed fills of the Newark (NY for inferring the flow directions of the Quaternary continental glaciers. The most-recent glacier (Woodfordian that this glacier did not reach much of Long Island and thus did not deposit the Harbor Hill Moraine. The next

  20. SITN Regional Outreach Map

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Region States in Region Awardee(s) Location of Awardee(s) Contact(s) Northeast (Photovoltaics) CT * ME * MA * NH NY * RI * VT Hudson Valley Community College Troy, NY Richard...

  1. Muon Acceleration in Cosmic-ray Sources

    E-Print Network [OSTI]

    Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

    2012-08-09T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

  2. Two source emission behavior of projectile fragments alpha in 84^Kr interactions at around 1 GeV per nucleon

    E-Print Network [OSTI]

    M. K. Singh; Ramji Pathak; V. Singh

    2010-08-12T23:59:59.000Z

    The emission of projectile fragments alpha has been studied in 84^Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source.

  3. DC source assemblies

    DOE Patents [OSTI]

    Campbell, Jeremy B; Newson, Steve

    2013-02-26T23:59:59.000Z

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  4. Potential Economic Impacts from Offshore Wind in the Southeast Region (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-07-01T23:59:59.000Z

    Offshore wind is a clean, renewable source of energy and can be an economic driver in the United States. To better understand the employment opportunities and other potential regional economic impacts from offshore wind development, the U.S. Department of Energy (DOE) funded research that focuses on four regions of the country. The studies use multiple scenarios with various local job and domestic manufacturing content assumptions. Each regional study uses the new offshore wind Jobs and Economic Development Impacts (JEDI) model, developed by the National Renewable Energy Laboratory. This fact sheet summarizes the potential economic impacts identified by the study for the Southeast (defined here as Georgia, South Carolina, North Carolina, and Virginia).

  5. Multi-source ion funnel

    DOE Patents [OSTI]

    Tang, Keqi; Belov, Mikhail B.; Tolmachev, Aleksey V.; Udseth, Harold R.; Smith, Richard D.

    2005-12-27T23:59:59.000Z

    A method for introducing ions generated in a region of relatively high pressure into a region of relatively low pressure by providing at least two electrospray ion sources, providing at least two capillary inlets configured to direct ions generated by the electrospray sources into and through each of the capillary inlets, providing at least two sets of primary elements having apertures, each set of elements having a receiving end and an emitting end, the primary sets of elements configured to receive a ions from the capillary inlets at the receiving ends, and providing a secondary set of elements having apertures having a receiving end and an emitting end, the secondary set of elements configured to receive said ions from the emitting end of the primary sets of elements and emit said ions from said emitting end of the secondary set of elements. The method may further include the step of providing at least one jet disturber positioned within at least one of the sets of primary elements, providing a voltage, such as a dc voltage, in the jet disturber, thereby adjusting the transmission of ions through at least one of the sets of primary elements.

  6. artificial neutrino source: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    neutrino sources. Predictions of models of some of the leading candidate sources, gamma-ray bursts and micro-quasars, are discussed, and the question of what can be learned from...

  7. Secret-Key Generation Using Correlated Sources and Channels

    E-Print Network [OSTI]

    Khisti, Ashish

    We study the secret-key capacity in a joint source-channel coding setup-the terminals are connected over a discrete memoryless channel and have access to side information, modelled as a pair of discrete memoryless source ...

  8. Glaciation and saline-freshwater mixing as a possible cause of cave formation in the eastern midcontinent region of the United States: A conceptual model

    SciTech Connect (OSTI)

    Panno, S.V. (Illinois State Geological Survey, Champaign (USA)); Bourcier, W.L. (Lawrence Livermore National Lab., CA (USA))

    1990-08-01T23:59:59.000Z

    We present a hypothesis for the formation of caves and associated karst features near the southern margins of the Illinois, Michigan, and Appalachian basins. Spatial and temporal relations among intracratonic basins, karstic terrain, and continental glaciation suggest that Pleistocene glaciation may have initiated the discharge of saline waters from the margins of these basins. Glaciation-induced discharge of saline waters could result from the consolidation of sediments due to the overlying pressure of glacial ice, and flushing of underlying aquifers as a result of bottom melting in recharge areas of basic aquifers. The upward migration of basin-derived saline waters into near-surface aquifers would result in the mixing of saline waters with infiltrating glacial meltwater and meteoric water. The development of a vertically restricted zone of mixing of saline and fresh water in limestone aquifers would result in the dissolution of limestone; this mechanism could be responsible for the formation, or at least the initiation of, some caves and associated karst features in the midcontinent region.

  9. XMM-Newton observations of M31: X-ray properties of radio sources and SNR candidates

    E-Print Network [OSTI]

    Sergey Trudolyubov; William Priedhorsky

    2004-04-29T23:59:59.000Z

    We present the results of the ongoing XMM-Newton survey of M31. 17 X-ray sources detected in the survey have bright radio counterparts, and 15 X-ray sources coincide with SNR candidates from optical and radio surveys. 15 out of 17 sources with radio counterparts, not SNR candidates, have spectral properties similar to that observed for background radio galaxies/quasars or Crab-like supernova remnants located in M31. The remaining two sources, XMMU J004046.8+405525 and XMMU J004249.1+412407, have soft X-ray spectra, and are associated with spatially resolved H-alpha emission regions, which makes them two new SNR candidates in M31. The observed absorbed X-ray luminosities of SNR candidates in our sample range from 1e35 to 5e36 ergs/s, assuming the distance of 760 kpc. Most of the SNR candidates detected in our survey have soft X-ray spectra. The spectra of the brightest sources show presence of emission lines and can be fit by thermal plasma models with kT~0.1-0.4 keV. The results of spectral fitting of SNR candidates suggest that most of them should be located in a relatively low density regions. We show that X-ray color-color diagrams can be useful tool for distinguishing between intrinsically hard background radio sources and Crab-like SNR and thermal SNR in M31 with soft spectra.

  10. Sources of the Radio Background Considered

    SciTech Connect (OSTI)

    Singal, J.; /KIPAC, Menlo Park /Stanford U.; Stawarz, L.; /KIPAC, Menlo Park /Stanford U. /Jagiellonian U., Astron. Observ.; Lawrence, A.; /Edinburgh U., Inst. Astron. /KIPAC, Menlo Park /Stanford U.; Petrosian, V.; /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., Appl. Phys. Dept.

    2011-08-22T23:59:59.000Z

    We investigate possible origins of the extragalactic radio background reported by the ARCADE 2 collaboration. The surface brightness of the background is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, we conclude that most of the radio background is produced by radio point sources that dominate at sub {mu}Jy fluxes. We show that a truly diffuse background produced by elections far from galaxies is ruled out because such energetic electrons would overproduce the observed X-ray/{gamma}-ray background through inverse Compton scattering of the other photon fields. Unrecognized flux from low surface brightness regions of extended radio sources, or moderate flux sources missed entirely by radio source count surveys, cannot explain the bulk of the observed background, but may contribute as much as 10%. We consider both radio supernovae and radio quiet quasars as candidate sources for the background, and show that both fail to produce it at the observed level because of insufficient number of objects and total flux, although radio quiet quasars contribute at the level of at least a few percent. We conclude that the most important population for production of the background is likely ordinary starforming galaxies above redshift 1 characterized by an evolving radio far-infrared correlation, which increases toward the radio loud with redshift.

  11. Interplay of the emission from thermal and direct sources in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Piotr Bozek

    2008-11-12T23:59:59.000Z

    The separation of the source created in ultrarelativistic heavy-ion collisions into a thermalized dense core and an outer mantle consisting of independent nucleon-nucleon collisions is discussed. Evidence for such a two component picture is found in transverse mass spectra of kaon, protons and antiprotons produced in Au-Au collisions at 200GeV. Estimates of the sizes of the thermal and direct sources are compared to models separating the interaction zone into a core and a corona, according to the density of participants or to the number of collisions. Consequences for the modeling of the dynamics of the small size, thermalized core are described. New initial conditions corresponding to the dense core lead to a stronger azimuthal asymmetry of the hydrodynamically expanding fireball, pressure gradients also increase. 2+1-dimensional hydrodynamic simulations are presented starting from all the matter in the interaction region or from the dense, thermal part of the source. We find faster transverse expansion and stronger elliptic flow for dense core initial conditions. For different impact parameters we find very similar spectra of the thermal part of the source and only adding particles emitted directly from nucleon-nucleon collisions in the corona the experimentally observed softening of the spectra with increasing impact parameter is reproduced. The elliptic flow is stronger for particles emitted from a source separated into a core and a corona.

  12. Oils and source rocks from the Anadarko Basin: Final report, March 1, 1985-March 15, 1995

    SciTech Connect (OSTI)

    Philp, R. P. [School of Geology and Geophysics, Univ. of Oklahoma, Norman, OK (United States)

    1996-11-01T23:59:59.000Z

    The research project investigated various geochemical aspects of oils, suspected source rocks, and tar sands collected from the Anadarko Basin, Oklahoma. The information has been used, in general, to investigate possible sources for the oils in the basin, to study mechanisms of oil generation and migration, and characterization of depositional environments. The major thrust of the recent work involved characterization of potential source formations in the Basin in addition to the Woodford shale. The formations evaluated included the Morrow, Springer, Viola, Arbuckle, Oil Creek, and Sylvan shales. A good distribution of these samples was obtained from throughout the basin and were evaluated in terms of source potential and thermal maturity based on geochemical characteristics. The data were incorporated into a basin modelling program aimed at predicting the quantities of oil that could, potentially, have been generated from each formation. The study of crude oils was extended from our earlier work to cover a much wider area of the basin to determine the distribution of genetically-related oils, and whether or not they were derived from single or multiple sources, as well as attempting to correlate them with their suspected source formations. Recent studies in our laboratory also demonstrated the presence of high molecular weight components(C{sub 4}-C{sub 80}) in oils and waxes from drill pipes of various wells in the region. Results from such a study will have possible ramifications for enhanced oil recovery and reservoir engineering studies.

  13. Source rock study of Smackover Formation from east Texas to Florida

    SciTech Connect (OSTI)

    Sassen, R.; Moore, C.H.

    1987-05-01T23:59:59.000Z

    Analyses of core and crude oil samples indicate that the laminated lime mudstone facies of the lower Smackover Formation is a significant source rock across the trend. The source facies was deposited in an anoxic and hypersaline environment that permitted preservation of algal kerogen. Moreover, source potential also occurs in undifferentiated Gilmer-Smackover rocks of east Texas deposited in a carbonate slope environment. Thermal maturity is the key factor that controls the generation of crude oil by the carbonate source facies and the eventual destruction of hydrocarbons in upper Smackover and Norphlet reservoirs. Once the regional thermal maturity framework is understood, it is possible to construct a source rock model that explains the distribution of crude oil, gas condensate, and methane across the trend. Calculated thermal maturity histories provide insight to the timing of hydrocarbon generation and migration and to the timing of hydrocarbon destruction and sulfate reduction in deep reservoirs. Basic geochemical strategies for exploration are suggested. One strategy is to focus exploration effort on traps formed prior to the time of crude oil migration that were nearest to effective source rocks. Another strategy is to avoid drilling reservoir rocks that are thermally overmature for preservation of hydrocarbons.

  14. A Geographic Information System approach to modeling nutrient and sediment transport

    SciTech Connect (OSTI)

    Levine, D.A. [Automated Sciences Group, Inc., Oak Ridge, TN (United States); Hunsaker, C.T.; Beauchamp, J.J. [Oak Ridge National Lab., TN (United States); Timmins, S.P. [Analysas Corp., Oak Ridge, TN (United States)

    1993-02-01T23:59:59.000Z

    The objective of this study was to develop a water quality model to quantify nonpoint-source (NPS) pollution that uses a geographic information system (GIS) to link statistical modeling of nutrient and sediment delivery with the spatial arrangement of the parameters that drive the model. The model predicts annual nutrient and sediment loading and was developed, calibrated, and tested on 12 watersheds within the Lake Ray Roberts drainage basin in north Texas. Three physiographic regions are represented by these watersheds, and model success, as measured by the accuracy of load estimates, was compared within and across these regions.

  15. Global atmospheric transport and source-receptor1 relationships for arsenic2

    E-Print Network [OSTI]

    Wu, Shiliang

    important anthropogenic arsenic sources7-10 with45 copper smelting being the dominant source6 contributions from anthropogenic sources. Metal (copper, zinc and lead)44 smelting and coal combustion are two 11 . In China and Chile, the dominated arsenic source55 #12;4 regions in northern and southern

  16. The Effects of Great Plains Irrigation on the Surface Energy Balance, Regional Circulation, and Precipitation

    E-Print Network [OSTI]

    Huber, David B.; Brunsell, Nathaniel A.; Mechem, David B.

    2014-05-05T23:59:59.000Z

    Irrigation provides a needed source of water in regions of low precipitation. Adding water to a region that would otherwise see little natural precipitation alters the partitioning of surface energy fluxes, the evolution of the planetary boundary...

  17. A Hierarchical Evaluation of Regional Climate Simulations

    SciTech Connect (OSTI)

    Leung, Lai-Yung R.; Ringler, Todd; Collins, William D.; Taylor, Mark; Ashfaq, Moetasim

    2013-08-20T23:59:59.000Z

    Global climate models (GCMs) are the primary tools for predicting the evolution of the climate system. Through decades of development, GCMs have demonstrated useful skill in simulating climate at continental to global scales. However, large uncertainties remain in projecting climate change at regional scales, which limit our ability to inform decisions on climate change adaptation and mitigation. To bridge this gap, different modeling approaches including nested regional climate models (RCMs), global stretch-grid models, and global high-resolution atmospheric models have been used to provide regional climate simulations (Leung et al. 2003). In previous efforts to evaluate these approaches, isolating their relative merits was not possible because factors such as dynamical frameworks, physics parameterizations, and model resolutions were not systematically constrained. With advances in high performance computing, it is now feasible to run coupled atmosphere-ocean GCMs at horizontal resolution comparable to what RCMs use today. Global models with local refinement using unstructured grids have become available for modeling regional climate (e.g., Rauscher et al. 2012; Ringler et al. 2013). While they offer opportunities to improve climate simulations, significant efforts are needed to test their veracity for regional-scale climate simulations.

  18. E-Print Network 3.0 - appalachian mountain region Sample Search...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (GRAM) Program Award. Graduate School, Appalachian State University. "Arid region... of stream restoration on woody riparian vegetation of Southern ... Source: Collection:...

  19. Muon acceleration in cosmic-ray sources

    SciTech Connect (OSTI)

    Klein, Spencer R.; Mikkelsen, Rune E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Becker Tjus, Julia [Fakultät für Physik and Astronomie, Theoretische Physik I, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2013-12-20T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 10{sup 13} keV cm{sup –1}. At gradients above 1.6 keV cm{sup –1}, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  20. Chandra Study of the Cepheus B Star Forming Region: Stellar Populations and the Initial Mass Function

    E-Print Network [OSTI]

    Konstantin V. Getman; Eric D. Feigelson; Leisa Townsley; Patrick Broos; Gordon Garmire; Masahiro Tsujimoto

    2006-01-18T23:59:59.000Z

    Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1 kpc, has been observed with the ACIS detector on board the Chandra X-ray Observatory. We detect 431 X-ray sources, of which 89% are confidently identified as clustered pre-main sequence stars. Two main results are obtained. First, we provide the best census to date for the stellar population of the region. We identify many members of two rich stellar clusters: the lightly obscured Cep OB3b association, and the deeply embedded cluster in Cep B whose existence was previously traced only by a handful of radio sources and T Tauri stars. Second, we find a discrepancy between the X-ray Luminosity Functions of the Cep OB3b and the Orion Nebula Cluster. This may be due to different Initial Mass Functions of two regions (excess of ~0.3 solar mass stars), or different age distributions. Several other results are obtained. A diffuse X-ray component seen in the field is attributed to the integrated emission of unresolved low mass PMS stars. The X-ray emission from HD 217086 (O7n), the principle ionizing source of the region, follows the standard model involving many small shocks in an unmagnetized radiatively accelerated wind. The X-ray source #294 joins a number of similar superflare PMS stars where long magnetic structures may connect the protoplanetary disk to the stellar surface.