Sample records for distribution model regions

  1. 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

  2. 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

  3. 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

  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. book review: Species distribution models for species distribution modellers

    E-Print Network [OSTI]

    Dormann, Carsten F

    2012-01-01T23:59:59.000Z

    Mapping  species  distributions:  spa? tial inference and news and update  book review  Species distribution models for species distribution modellers  Ecological niches and 

  6. 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.

  7. Regional distribution of diagenetic carbonate cement in Palaeocene deepwater

    E-Print Network [OSTI]

    Haszeldine, Stuart

    Regional distribution of diagenetic carbonate cement in Palaeocene deepwater sandstones: North Sea. This study attempts to make a large-scale regional examination of the distribution of carbonate cements

  8. EMISSION MEASURE DISTRIBUTION AND HEATING OF TWO ACTIVE REGION CORES

    SciTech Connect (OSTI)

    Tripathi, Durgesh [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411 007 (India); Klimchuk, James A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Mason, Helen E., E-mail: durgesh@iucaa.ernet.in [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2011-10-20T23:59:59.000Z

    Using data from the Extreme-ultraviolet Imaging Spectrometer aboard Hinode, we have studied the coronal plasma in the core of two active regions. Concentrating on the area between opposite polarity moss, we found emission measure distributions having an approximate power-law form EM{proportional_to}T{sup 2.4} from log T = 5.5 up to a peak at log T = 6.55. We show that the observations compare very favorably with a simple model of nanoflare-heated loop strands. They also appear to be consistent with more sophisticated nanoflare models. However, in the absence of additional constraints, steady heating is also a viable explanation.

  9. 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 ...

  10. From Logical to Distributional Models

    E-Print Network [OSTI]

    Anne Preller

    2014-12-30T23:59:59.000Z

    The paper relates two variants of semantic models for natural language, logical functional models and compositional distributional vector space models, by transferring the logic and reasoning from the logical to the distributional models. The geometrical operations of quantum logic are reformulated as algebraic operations on vectors. A map from functional models to vector space models makes it possible to compare the meaning of sentences word by word.

  11. On the Fractal Distribution of HII Regions in Disk Galaxies

    E-Print Network [OSTI]

    Nestor Sanchez; Emilio J. Alfaro

    2008-10-02T23:59:59.000Z

    In this work we quantify the degree to which star-forming events are clumped. We apply a precise and accurate technique to calculate the correlation dimension Dc of the distribution of HII regions in a sample of disk galaxies. Our reliable results are distributed in the range 1.5fractal dimension among galaxies, contrary to a universal picture sometimes claimed in literature. The faintest galaxies tend to distribute their HII regions in more clustered (less uniform) patterns. Moreover, the fractal dimension for the brightest HII regions within the same galaxy seems to be smaller than for the faintest ones suggesting some kind of evolutionary effect.

  12. 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") ...

  13. 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.

  14. The Fractal Distribution of HII Regions in Disk Galaxies

    E-Print Network [OSTI]

    Nestor Sanchez; Emilio J. Alfaro

    2008-04-29T23:59:59.000Z

    It is known that the gas has a fractal structure in a wide range of spatial scales with a fractal dimension that seems to be a constant around Df = 2.7. It is expected that stars forming from this fractal medium exhibit similar fractal patterns. Here we address this issue by quantifying the degree to which star-forming events are clumped. We develop, test, and apply a precise and accurate technique to calculate the correlation dimension Dc of the distribution of HII regions in a sample of disk galaxies. We find that the determination of Dc is limited by the number of HII regions, since if there are fractal dimension among galaxies, contrary to a universal picture sometimes claimed in literature. The fractal dimension exhibits a weak but significant correlation with the absolute magnitude and, to a lesser extent, with the galactic radius. The faintest galaxies tend to distribute their HII regions in more clustered (less uniform) patterns. The fractal dimension for the brightest HII regions within the same galaxy seems to be smaller than for the faintest ones suggesting some kind of evolutionary efffect, but the obtained correlation remains unchanged if only the brightest regions are taken into account.

  15. 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.

  16. Distributed Energy Resources Market Diffusion Model

    SciTech Connect (OSTI)

    Maribu, Karl Magnus; Firestone, Ryan; Marnay, Chris; Siddiqui,Afzal S.

    2006-06-16T23:59:59.000Z

    Distributed generation (DG) technologies, such as gas-fired reciprocating engines and microturbines, have been found to be economically beneficial in meeting commercial-sector electrical, heating, and cooling loads. Even though the electric-only efficiency of DG is lower than that offered by traditional central stations, combined heat and power (CHP) applications using recovered heat can make the overall system energy efficiency of distributed energy resources (DER) greater. From a policy perspective, however, it would be useful to have good estimates of penetration rates of DER under various economic and regulatory scenarios. In order to examine the extent to which DER systems may be adopted at a national level, we model the diffusion of DER in the US commercial building sector under different technical research and technology outreach scenarios. In this context, technology market diffusion is assumed to depend on the system's economic attractiveness and the developer's knowledge about the technology. The latter can be spread both by word-of-mouth and by public outreach programs. To account for regional differences in energy markets and climates, as well as the economic potential for different building types, optimal DER systems are found for several building types and regions. Technology diffusion is then predicted via two scenarios: a baseline scenario and a program scenario, in which more research improves DER performance and stronger technology outreach programs increase DER knowledge. The results depict a large and diverse market where both optimal installed capacity and profitability vary significantly across regions and building types. According to the technology diffusion model, the West region will take the lead in DER installations mainly due to high electricity prices, followed by a later adoption in the Northeast and Midwest regions. Since the DER market is in an early stage, both technology research and outreach programs have the potential to increase DER adoption, and thus, shift building energy consumption to a more efficient alternative.

  17. 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

  18. 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.

  19. New model for nucleon generalized parton distributions

    SciTech Connect (OSTI)

    Radyushkin, Anatoly V. [JLAB, Newport News, VA (United States)

    2014-01-01T23:59:59.000Z

    We describe a new type of models for nucleon generalized parton distributions (GPDs) H and E. They are heavily based on the fact nucleon GPDs require to use two forms of double distribution (DD) representations. The outcome of the new treatment is that the usual DD+D-term construction should be amended by an extra term, {xi} E{sub +}{sup 1} (x,{xi}) which has the DD structure {alpha}/{beta} e({beta},{alpha}, with e({beta},{alpha}) being the DD that generates GPD E(x,{xi}). We found that this function, unlike the D-term, has support in the whole -1 <= x <= 1 region. Furthermore, it does not vanish at the border points |x|={xi}.

  20. Photovoltaic subsystem marketing and distribution model: programming manual. Final report

    SciTech Connect (OSTI)

    Not Available

    1982-07-01T23:59:59.000Z

    Complete documentation of the marketing and distribution (M and D) computer model is provided. The purpose is to estimate the costs of selling and transporting photovoltaic solar energy products from the manufacturer to the final customer. The model adjusts for the inflation and regional differences in marketing and distribution costs. The model consists of three major components: the marketing submodel, the distribution submodel, and the financial submodel. The computer program is explained including the input requirements, output reports, subprograms and operating environment. The program specifications discuss maintaining the validity of the data and potential improvements. An example for a photovoltaic concentrator collector demonstrates the application of the model.

  1. Regional measurements of /sup 14/Cmisonidazole distribution and blood flow in subcutaneous RT-9 experimental tumors

    SciTech Connect (OSTI)

    Blasberg, R.; Horowitz, M.; Strong, J.; Molnar, P.; Patlak, C.; Owens, E.; Fenstermacher, J.

    1985-04-01T23:59:59.000Z

    Regional (/sup 14/C)misonidazole-derived radioactivity (MISO*) was measured by quantitative autoradiography in s.c. RT-9 experimental tumors 0.5, 2, and 4 h after an i.v. bolus (25 mg) and constant infusion (10 mg/h) in rats. Misonidazole (MISO) concentration in plasma, tumor, and other tissues was also measured by high-pressure liquid chromatography. The distribution of MISO* in the tumors always resulted in a characteristic pattern with high peripheral and low central values. The high-activity regions in the tumor rim achieved tissue: plasma MISO* activity ratios of 0.97 and 2.2 by 0.5 and 4 h, respectively; for central tumor regions, this ratio was 0.20 and 0.32 for the same periods, respectively. The limited distribution of MISO* to central tumor regions could be correlated to low values of blood flow (measured with (/sup 131/I)iodoantipyrine) and to diffusion from peripheral tumor regions. Low blood flow in the central regions of these tumors will significantly limit the distribution of MISO and other drugs to viable-appearing cells in these areas and could account in part for the failures of chemotherapy in certain solid tumors. Pharmacokinetic modeling indicates that 1 to 9 h may be necessary for MISO concentrations in some tumor regions to reach 50% of that in plasma.

  2. Visualizing highdimensional posterior distributions in Bayesian modeling

    E-Print Network [OSTI]

    Kaski, Samuel

    Visualizing high­dimensional posterior distributions in Bayesian modeling Jarkko Venna and Samuel on the posterior distribution of the model parameters. The closed­form solution is seldom known and samples distributions; the current method is based on Self­Organizing Maps and Fisher metrics. Sample applications have

  3. 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.

  4. Distributed Probabilistic Model-Building Genetic Algorithm

    E-Print Network [OSTI]

    Dongarra, Jack

    is considered by Principal Component Analysis (PCA) when the off- springs are generated. The island modelDistributed Probabilistic Model-Building Genetic Algorithm Tomoyuki Hiroyasu1 , Mitsunori Miki1), Distributed PMBGA (DPMBGA), is proposed. In the DPMBGA, the correlation among the design variables

  5. Modeling hydrogen fuel distribution infrastructure

    E-Print Network [OSTI]

    Pulido, Jon R. (Jon Ramon), 1974-

    2004-01-01T23:59:59.000Z

    This thesis' fundamental research question is to evaluate the structure of the hydrogen production, distribution, and dispensing infrastructure under various scenarios and to discover if any trends become apparent after ...

  6. Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

    SciTech Connect (OSTI)

    NONE

    1995-02-17T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A.

  7. A distributed accelerated gradient algorithm for distributed model predictive

    E-Print Network [OSTI]

    Como, Giacomo

    of hydro power plants is to manage the available water resources efficiently, while following an optimal is applied to the power reference tracking problem of a hydro power valley (HPV) system. The applied power control, Distributed optimization, Accelerated gradient algorithm, Model predictive control

  8. Survey of Emissions Models for Distributed Combined Heat and...

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

    Survey of Emissions Models for Distributed Combined Heat and Power Systems, 2007 Survey of Emissions Models for Distributed Combined Heat and Power Systems, 2007 The models...

  9. Gas Distribution Modeling using Sparse Gaussian Process Mixture Models

    E-Print Network [OSTI]

    Stachniss, Cyrill

    Gas Distribution Modeling using Sparse Gaussian Process Mixture Models Cyrill Stachniss1 Christian-- In this paper, we consider the problem of learning a two dimensional spatial model of a gas distribution with a mobile robot. Building maps that can be used to accurately predict the gas concentration at query

  10. 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...

  11. Convex Models of Distribution System Reconfiguration

    E-Print Network [OSTI]

    Taylor, Joshua A.

    We derive new mixed-integer quadratic, quadratically constrained, and second-order cone programming models of distribution system reconfiguration, which are to date the first formulations of the ac problem that have convex, ...

  12. Explaining species distribution patterns through hierarchical modeling

    E-Print Network [OSTI]

    Gelfand, Alan E.; Silander, John A., Jr.; Wu, Shanshan; Latimer, Andrew; Lewis, Paul O.; Rebelo, Anthony G.; Holder, Mark T.

    2006-01-01T23:59:59.000Z

    Bayesian Analysis (2006) 1, Number 1, pp. 41–92 Explaining Species Distribution Patterns through Hierarchical Modeling Alan E. Gelfand?, John A. Silander Jr†., Shanshan Wu‡, Andrew Latimer§, Paul O. Lewis¶, Anthony G. Rebelo? and Mark Holder..., spatial logistic re- gression, species range, species richness. 1 Introduction Ecologists increasingly use species distribution models to address theoretical and practi- cal issues including predicting the response of species to climate change (Midgley et...

  13. CAN A LONG NANOFLARE STORM EXPLAIN THE OBSERVED EMISSION MEASURE DISTRIBUTIONS IN ACTIVE REGION CORES?

    SciTech Connect (OSTI)

    Mulu-Moore, Fana M.; Winebarger, Amy R. [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States); Warren, Harry P., E-mail: fanamariam.mulumoore@nasa.gov [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2011-11-20T23:59:59.000Z

    All theories that attempt to explain the heating of the high-temperature plasma observed in the solar corona are based on short bursts of energy. The intensities and velocities measured in the cores of quiescent active regions, however, can be steady over many hours of observation. One heating scenario that has been proposed to reconcile such observations with impulsive heating models is the 'long nanoflare storm', where short-duration heating events occur infrequently on many sub-resolution strands; the emission of the strands is then averaged together to explain the observed steady structures. In this Letter, we examine the emission measure distribution predicted for such a long nanoflare storm by modeling an arcade of strands in an active region core. Comparisons of the computed emission measure distributions with recent observations indicate that the long nanoflare storm scenario implies greater than five times more 1 MK emission than is actually observed for all plausible combinations of loop lengths, heating rates, and abundances. We conjecture that if the plasma had 'super coronal' abundances, the model may be able to match the observations at low temperatures.

  14. Projected impacts of climate change on species distribution in the Acadian Forest region of eastern Nova Scotia

    E-Print Network [OSTI]

    .e., hydrological cycle and earth- sun geometry. Growing degree days and mean air temperature are basedProjected impacts of climate change on species distribution in the Acadian Forest region of eastern on processing remote sensing data, mean air temperatures serves as one of several inputs to model calculation

  15. Modeling of Customer Adoption of Distributed Energy Resources

    E-Print Network [OSTI]

    Modeling of Customer Adoption of Distributed Energy Resources CALIFORNIA ENERGY COMMISSION Reliability Technology Solutions Modeling of Customer Adoption of Distributed Energy Resources Prepared the consequences. #12;#12;Modeling of Customer Adoption of Distributed Energy Resources iii Table of Contents

  16. 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)...

  17. Distributed Wind Diffusion Model Overview (Presentation)

    SciTech Connect (OSTI)

    Preus, R.; Drury, E.; Sigrin, B.; Gleason, M.

    2014-07-01T23:59:59.000Z

    Distributed wind market demand is driven by current and future wind price and performance, along with several non-price market factors like financing terms, retail electricity rates and rate structures, future wind incentives, and others. We developed a new distributed wind technology diffusion model for the contiguous United States that combines hourly wind speed data at 200m resolution with high resolution electricity load data for various consumer segments (e.g., residential, commercial, industrial), electricity rates and rate structures for utility service territories, incentive data, and high resolution tree cover. The model first calculates the economics of distributed wind at high spatial resolution for each market segment, and then uses a Bass diffusion framework to estimate the evolution of market demand over time. The model provides a fundamental new tool for characterizing how distributed wind market potential could be impacted by a range of future conditions, such as electricity price escalations, improvements in wind generator performance and installed cost, and new financing structures. This paper describes model methodology and presents sample results for distributed wind market potential in the contiguous U.S. through 2050.

  18. 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.

  19. A Formal Model of Provenance in Distributed Systems

    E-Print Network [OSTI]

    Francalanza, Adrian

    A Formal Model of Provenance in Distributed Systems Issam Souilah2 Adrian Francalanza1 Vladimiro;Motivation Trust In a Distributed System #12;Motivation Trust In a Distributed System Distribution inherent parallelism. #12;Motivation Trust In a Distributed System Distribution inherent parallelism. Distribution

  20. Hot Water Distribution System Model Enhancements

    SciTech Connect (OSTI)

    Hoeschele, M.; Weitzel, E.

    2012-11-01T23:59:59.000Z

    This project involves enhancement of the HWSIM distribution system model to more accurately model pipe heat transfer. Recent laboratory testing efforts have indicated that the modeling of radiant heat transfer effects is needed to accurately characterize piping heat loss. An analytical methodology for integrating radiant heat transfer was implemented with HWSIM. Laboratory test data collected in another project was then used to validate the model for a variety of uninsulated and insulated pipe cases (copper, PEX, and CPVC). Results appear favorable, with typical deviations from lab results less than 8%.

  1. Synthesised Constraint Models for Distributed Energy Management

    E-Print Network [OSTI]

    Reif, Wolfgang

    generation [1], demand-side manage- ment, or building control software. In a producer-based view, supplySynthesised Constraint Models for Distributed Energy Management Alexander Schiendorfer, Jan frequently encountered in energy management systems such as the coordination of power generators in a virtual

  2. A void distribution model-flashing flow

    SciTech Connect (OSTI)

    Riznic, J.; Ishii, M.; Afgan, N.

    1987-01-01T23:59:59.000Z

    A new model for flashing flow based on wall nucleations is proposed here and the model predictions are compared with some experimental data. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites was used. Thus it was possible to avoid the usual assumption of a constant bubble number density. Comparisons of the model with the data shows that the model based on the nucleation site density correlation appears to be acceptable to describe the vapor generation in the flashing flow. For the limited data examined, the comparisons show rather satisfactory agreement without using a floating parameter to adjust the model. This result indicated that, at least for the experimental conditions considered here, the mechanistic predictions of the flashing phenomenon is possible on the present wall nucleation based model.

  3. A Service Oriented Architecture for Exploring High Performance Distributed Power Models

    SciTech Connect (OSTI)

    Liu, Yan; Chase, Jared M.; Gorton, Ian

    2012-11-12T23:59:59.000Z

    Power grids are increasingly incorporating high quality, high throughput sensor devices inside power distribution networks. These devices are driving an unprecedented increase in the volume and rate of available information. The real-time requirements for handling this data are beyond the capacity of conventional power models running in central utilities. Hence, we are exploring distributed power models deployed at the regional scale. The connection of these models for a larger geographic region is supported by a distributed system architecture. This architecture is built in a service oriented style, whereby distributed power models running on high performance clusters are exposed as services. Each service is semantically annotated and therefore can be discovered through a service catalog and composed into workflows. The overall architecture has been implemented as an integrated workflow environment useful for power researchers to explore newly developed distributed power models.

  4. Modeling of Distributed Systems by Concurrent Regular Expressions

    E-Print Network [OSTI]

    Garg, Vijay

    Modeling of Distributed Systems by Concurrent Regular Expressions Vijay K. Garg Department of Electrical and Computer Engineering, University of Texas, Austin, TX 78712 We propose an algebraic model called concurrent regular expressions for modeling and anal- ysis of distributed systems

  5. Modeling of Distributed Systems by Concurrent Regular Expressions

    E-Print Network [OSTI]

    Garg, Vijay

    Modeling of Distributed Systems by Concurrent Regular Expressions Vijay K. Garg Department of Electrical and Computer Engineering, University of Texas, Austin, TX 78712 We propose an algebraic model called concurrent regular expressions for modeling and anal­ ysis of distributed systems

  6. Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

    SciTech Connect (OSTI)

    NONE

    1998-01-01T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. Subsequent chapters of this report provide: an overview of NGTDM; a description of the interface between the NEMS and NGTDM; an overview of the solution methodology of the NGTDM; the solution methodology for the Annual Flow Module; the solution methodology for the Distributor Tariff Module; the solution methodology for the Capacity Expansion Module; the solution methodology for the Pipeline Tariff Module; and a description of model assumptions, inputs, and outputs.

  7. 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) ...

  8. Husimi distribution function and one-dimensional Ising model

    E-Print Network [OSTI]

    F. Kheirandish

    2005-12-24T23:59:59.000Z

    Husimi distribution function for the one-dimensional Ising model is obtained. One-point and joint distribution functions are calculated and their thermal behaviour are discussed.

  9. Electrical Model Development and Validation for Distributed Resources

    SciTech Connect (OSTI)

    Simoes, M. G.; Palle, B.; Chakraborty, S.; Uriarte, C.

    2007-04-01T23:59:59.000Z

    This project focuses on the development of electrical models for small (1-MW) distributed resources at the National Renewable Energy Laboratory's Distributed Energy Resources Test Facility.

  10. 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...

  11. 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...

  12. 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...

  13. A Model of U.S. Commercial Distributed Generation Adoption

    SciTech Connect (OSTI)

    LaCommare, Kristina Hamachi; Ryan Firestone; Zhou, Nan; Maribu,Karl; Marnay, Chris

    2006-01-10T23:59:59.000Z

    Small-scale (100 kW-5 MW) on-site distributed generation (DG) economically driven by combined heat and power (CHP) applications and, in some cases, reliability concerns will likely emerge as a common feature of commercial building energy systems over the next two decades. Forecasts of DG adoption published by the Energy Information Administration (EIA) in the Annual Energy Outlook (AEO) are made using the National Energy Modeling System (NEMS), which has a forecasting module that predicts the penetration of several possible commercial building DG technologies over the period 2005-2025. NEMS is also used for estimating the future benefits of Department of Energy research and development used in support of budget requests and management decisionmaking. The NEMS approach to modeling DG has some limitations, including constraints on the amount of DG allowed for retrofits to existing buildings and a small number of possible sizes for each DG technology. An alternative approach called Commercial Sector Model (ComSeM) is developed to improve the way in which DG adoption is modeled. The approach incorporates load shapes for specific end uses in specific building types in specific regions, e.g., cooling in hospitals in Atlanta or space heating in Chicago offices. The Distributed Energy Resources Customer Adoption Model (DER-CAM) uses these load profiles together with input cost and performance DG technology assumptions to model the potential DG adoption for four selected cities and two sizes of five building types in selected forecast years to 2022. The Distributed Energy Resources Market Diffusion Model (DER-MaDiM) is then used to then tailor the DER-CAM results to adoption projections for the entire U.S. commercial sector for all forecast years from 2007-2025. This process is conducted such that the structure of results are consistent with the structure of NEMS, and can be re-injected into NEMS that can then be used to integrate adoption results into a full forecast.

  14. Nutrient and dissolved-oxygen distributions in the Gulf of Mexico and adjacent regions

    E-Print Network [OSTI]

    Morrison, John Miller

    1974-01-01T23:59:59.000Z

    renuirezent . d'or the u. =. p 'e= o 1 LA S 1" R G P S C I '"'11 C Z y Iis (h l1ajor Sub?-'er c: Ge, . anoSraoh; NUTRIENT AND DISSOLVED-OXYGE11 DISTRIBUTIONS XN THE GULF OF MEXICO AND ADJACENT REGIONS A Thesis by JOHN MILLER MORRXSON Approved... as to style and content by: (Chairman of Co ittee) (Head Department) (Member) (Me er) May &9yi) ABSTRACT Nutrient and. Dissolved-oxygen Distributions in the Gulf of Nexico and Adjacent Regions. (Nay 1974) John Miller Morrison~ B. A. , College...

  15. Using Model Checking for Analyzing Distributed Power Control Problems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Using Model Checking for Analyzing Distributed Power Control Problems Thomas Brihaye, Marc. Realizing that the distributed power control (PC) problem can be modeled by a timed game between a given Distributed power control, game theory, interference channel, model checking, timed games, verification

  16. Natural gas transmission and distribution model of the National Energy Modeling System

    SciTech Connect (OSTI)

    NONE

    1997-02-01T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of Integrated Analysis and Forecasting of the Energy Information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. From 1982 through 1993, the Intermediate Future Forecasting System (IFFS) was used by the EIA for its analyses, and the Gas Analysis Modeling System (GAMS) was used within IFFS to represent natural gas markets. Prior to 1982, the Midterm Energy Forecasting System (MEFS), also referred to as the Project Independence Evaluation System (PIES), was employed. NEMS was developed to enhance and update EIA`s modeling capability by internally incorporating models of energy markets that had previously been analyzed off-line. In addition, greater structural detail in NEMS permits the analysis of a broader range of energy issues. The time horizon of NEMS is the midterm period (i.e., through 2015). In order to represent the regional differences in energy markets, the component models of NEMS function at regional levels appropriate for the markets represented, with subsequent aggregation/disaggregation to the Census Division level for reporting purposes.

  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. 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 ...

  19. 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 ...

  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. Distributed energy resources in practice: A case study analysis and validation of LBNL's customer adoption model

    E-Print Network [OSTI]

    Bailey, Owen; Creighton, Charles; Firestone, Ryan; Marnay, Chris; Stadler, Michael

    2003-01-01T23:59:59.000Z

    Pharmingen Distributed Energy Resources in Practice Tablemany regions. Distributed Energy Resources in Practice 10.of µGrid Distributed Energy Resource Potential Using DER-CAM

  2. Measurement and Modeling of Spatial NH3 Storage Distributions...

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

    NH3 Storage Distributions in a Commercial Small Port Cu Zeolite Urea SCR Catalyst Measurement and Modeling of Spatial NH3 Storage Distributions in a Commercial Small Port Cu...

  3. 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.

  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. Analysis Model for Domestic Hot Water Distribution Systems: Preprint

    SciTech Connect (OSTI)

    Maguire, J.; Krarti, M.; Fang, X.

    2011-11-01T23:59:59.000Z

    A thermal model was developed to estimate the energy losses from prototypical domestic hot water (DHW) distribution systems for homes. The developed model, using the TRNSYS simulation software, allows researchers and designers to better evaluate the performance of hot water distribution systems in homes. Modeling results were compared with past experimental study results and showed good agreement.

  6. Synthesis of Seafood Catch, Distribution, and Consumption Patterns in the Gulf of Mexico Region

    SciTech Connect (OSTI)

    Steimle and Associates, Inc.

    1999-08-16T23:59:59.000Z

    The purpose of this task was to gather and assemble information that will provide a synthesis of seafood catch, distribution and consumption patterns for the Gulf of Mexico (GOM) region. This task was part of a U.S. Department of Energy (DOE)-sponsored project entitled ''Environmental and Economic Assessment of Discharges from Gulf of Mexico Region Oil and Gas Operations.'' Personal interviews were conducted with a total of 905 recreational fishermen and 218 commercial fishermen (inclusive of shrimpers, crabbers, oystermen and finfishermen) in Louisiana and Texas using survey questionnaires developed for the study. Results of these interviews detail the species and quantities caught, location of catch, mode of fishing, distribution of catch, family consumption patterns and demographics of the fishermen.

  7. Model of the radial distribution of gas in the blast furnace

    SciTech Connect (OSTI)

    Nikus, M.; Saxen, H. [Aabo Akademi Univ. (Finland). Dept. of Chemical Engineering

    1996-12-31T23:59:59.000Z

    This paper describes an on-line model for estimating the radial gas distribution in blast furnaces. The model is based on molar and energy flow balances for the blast furnace throat region, and utilizes the top gas temperature and gas temperature measurements from a fixed above-burden probe. The distribution of the gas flux is estimated by a Kalman filter. The method is illustrated to capture short-term dynamics and to detect sudden major changes in the gas distribution in Finnish blast furnace.

  8. 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.

  9. 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.

  10. Regional Portfolio Model ResultsRegional Portfolio Model Results Michael Schilmoeller

    E-Print Network [OSTI]

    Plans on the efficient frontier Interpreting a plan Issue Studies Carbon control and climate changeChanges in Assumptions and Data CO2 penalty likelihood distribution Conservation base case New programs and re on the efficient frontier Interpreting a plan Issue Studies Carbon control and climate change The economic effects

  11. New approach for modelling distributed MEMS transmission lines

    E-Print Network [OSTI]

    Akin, Tayfun

    New approach for modelling distributed MEMS transmission lines K. Topalli, M. Unlu, S. Demir, O for the distributed MEMS transmission line (DMTL) structures. In this new model, the MEMS bridges that are used as the loading elements of the DMTL structures are represented as low-impedance transmission lines, rather than

  12. Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics S. K. Patil, M. Y, USA Modeling of electrostatic field distribution and energy storage in diphasic dielectrics containing to the increased energy storage density. For composites with lower volume fractions of high-permittivity inclusions

  13. 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...

  14. 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

  15. 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

  16. 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

  17. Distributed Temporal Logic for the Analysis of Security Protocol Models

    E-Print Network [OSTI]

    Basin, David

    , showing that it is sufficient to consider models in which the intruder completely controls the networkDistributed Temporal Logic for the Analysis of Security Protocol Models David Basin Department to reason about and relate different security-protocol models. This includes reasoning about model

  18. Action Models: A Reliability Modeling Formalism for Fault-Tolerant Distributed Computing Systems

    E-Print Network [OSTI]

    Newcastle upon Tyne, University of

    Action Models: A Reliability Modeling Formalism for Fault-Tolerant Distributed Computing Systems. Introduction Model-based evaluation of the reliability of distributed systems has traditionally required expert- proach to analyze the reliability of fault-tolerant distributed systems. More in particular, we want

  19. Modeling Data using Directional Distributions Acknowledgements

    E-Print Network [OSTI]

    Sra, Suvrit

    , rather than its magnitudes. For example, modeling wind current directions, modeling geomagnetism, measurements corresponding to the position of the clock hands and modeling text data, all seem to require a cosine similarity measure often far outperforms using a traditional Euclidean distance metric

  20. Modeling and Verification of Distributed Generation and Voltage Regulation Equipment for Unbalanced Distribution Power Systems; Annual Subcontract Report, June 2007

    SciTech Connect (OSTI)

    Davis, M. W.; Broadwater, R.; Hambrick, J.

    2007-07-01T23:59:59.000Z

    This report summarizes the development of models for distributed generation and distribution circuit voltage regulation equipment for unbalanced power systems and their verification through actual field measurements.

  1. Off-center HII regions in power-law density distributions

    E-Print Network [OSTI]

    S. J. Arthur

    2007-05-05T23:59:59.000Z

    The expansion of ionization fronts in uniform and spherically symmetric power-law density distributions is a well-studied topic. However, in many situations, such as a star formed at the edge of a molecular cloud core, an offset power-law density distribution would be more appropriate. In this paper a few of the main issues of the formation and expansion of HII regions in such media are outlined and results are presented for the particular cases where the underlying power laws are 1/r^2 and 1/r^3. A simple criterion is developed for determining whether the initial photoionized region will be unbounded, which depends on the power-law exponent and the ratio of the equivalent Stroemgren radius produced by the star in a uniform medium to the stellar offset distance. In the expansion stage, the ionized volumes will eventually become unbounded unless pressure balance with the external medium is reached before the ionization front velocity becomes supersonic with respect to the ionized gas.

  2. 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.

  3. 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

  4. Quantification of model mismatch errors of the dynamic energy distribution in a stirred-tank reactor

    E-Print Network [OSTI]

    Kimmich, Mark Raymond

    1987-01-01T23:59:59.000Z

    experiments Moo- Young and Chan (1971) proposed a model which consisted of a dual series of well-mixed regions and dead space in series with a plug- flow region. The system studied consisted of a viscous fluid flowing in a cylindrical tank fitted with four...QUANTIFICATION OF MODEL MISMATCH ERRORS OF THE DYNAMIC ENERGY DISTRIBUTION IN A STIRRED- TANK REACTOR A Thesis by MARK RAYMOND KIMMICH Submitted to the Graduate College of Texas AkM University in partial fulfillment of the requirement...

  5. Parton distribution functions and nuclear EMC effect in a statistical model

    E-Print Network [OSTI]

    Lijing Shao; Yunhua Zhang; Bo-Qiang Ma

    2010-08-11T23:59:59.000Z

    A new and simple statistical approach is performed to calculate the parton distribution functions (PDFs) of the nucleon in terms of light-front kinematic variables. Analytic expressions of x-dependent PDFs are obtained in the whole x region. And thereafter, we treat the temperature T as a parameter of the atomic number A to explain the nuclear EMC effect in the region $x \\in [0.2, 0.7]$. We give the predictions of PDF ratios, and they are very different from those by other models, thus experiments aiming at measuring PDF ratios are suggested to provide a discrimination of different models.

  6. Modeling Distribution Connected PV and Interconnection Study...

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

    load and solar variability Modelling regulator controls Interaction between smart inverters and regulator load drop compensator control 9 Base Case With PV Percent Change...

  7. Open economy models of distribution and growth Robert A. Blecker*

    E-Print Network [OSTI]

    Carlini, David

    Chapter 9 Open economy models of distribution and growth Robert A. Blecker* To appear in: Eckhard-Keynesian macro models for closed economies, the present chapter focuses on extensions of these models the post-Keynesian framework to a global economy that has become much more integrated in the past few

  8. Model Predictive Control for Smooth Distributed Power Adaptation

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Model Predictive Control for Smooth Distributed Power Adaptation Virgile Garcia1,2,3 , Nikolai the variations of other BS powers. The trajectories are then updated using a Model Predictive Control (MPC-based power control, no inter-cell cooperation, power trajectory, model predictive control, smooth power

  9. Non resonant transmission modelling with Statistical modal Energy distribution Analysis

    E-Print Network [OSTI]

    Boyer, Edmond

    be used as an alternative to Statistical Energy Analysis for describing subsystems with low modal overlap1 Non resonant transmission modelling with Statistical modal Energy distribution Analysis L. Maxit Capelle, F-69621 Villeurbanne Cedex, France Statistical modal Energy distribution Analysis (SmEdA) can

  10. 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.

  11. THE SPATIAL AGGREGATION LANGUAGE FOR MODELING AND CONTROLLING DISTRIBUTED

    E-Print Network [OSTI]

    Bailey-Kellogg, Chris

    THE SPATIAL AGGREGATION LANGUAGE FOR MODELING AND CONTROLLING DISTRIBUTED PHYSICAL SYSTEMS study novel approaches to decentralized control de- sign, in the context of thermal regulation important science and engineering applications, such as predicting weather patterns, controlling

  12. Modeling and Verification of a Distributed Transmission Protocol Lubomir Ivanov

    E-Print Network [OSTI]

    Ivanov, Lubomir

    -parallel poset verification is a powerful methodology for proving the design correctness of complex systemsModeling and Verification of a Distributed Transmission Protocol Lubomir Ivanov Department verification methodologies has evolved in two directions: powerful, general techniques capable of accurately

  13. Quark star model with charge distributions

    E-Print Network [OSTI]

    Manuel Malaver

    2014-07-08T23:59:59.000Z

    In this paper, we studied the behavior of relativistic objects with anisotropic matter distribution inthe presence of an electric field considering a gravitational potential Z(x) of Thirukkanesh and Ragel (2013) which depends on an adjustable parameter n. The equation of state presents a quadratic relation between the energy densityand the radial pressure. New exact solutions of the Einstein-Maxwell system are generated. A physical analysis of electromagnetic field indicates that is regular in the origin and well behaved. We show as a variation of the adjustable parameter n causes a modification in the charge density, the radial pressure and the mass of the stellar object.

  14. Modeling Potential DistributionModeling Potential Distribution of Common Plant Species inof Common Plant Species in

    E-Print Network [OSTI]

    that map unit. SSURGO, SMU W/ 4 Component Soils SSURGO, SMU W/ 4 Component Soils SWGap Land cover distribution within one SMU SWGap Land cover distribution within one SMU #12;Frequencyof

  15. Regional Analysis of Building Distributed Energy Costs and CO2 Abatement: A U.S. - China Comparison

    SciTech Connect (OSTI)

    Mendes, Goncalo; Feng, Wei; Stadler, Michael; Steinbach, Jan; Lai, Judy; Zhou, Nan; Marnay, Chris; Ding, Yan; Zhao, Jing; Tian, Zhe; Zhu, Neng

    2014-04-09T23:59:59.000Z

    The following paper conducts a regional analysis of the U.S. and Chinese buildings? potential for adopting Distributed Energy Resources (DER). The expected economics of DER in 2020-2025 is modeled for a commercial and a multi-family residential building in different climate zones. The optimal building energy economic performance is calculated using the Distributed Energy Resources Customer Adoption Model (DER CAM) which minimizes building energy costs for a typical reference year of operation. Several DER such as combined heat and power (CHP) units, photovoltaics, and battery storage are considered. The results indicate DER have economic and environmental competitiveness potential, especially for commercial buildings in hot and cold climates of both countries. In the U.S., the average expected energy cost savings in commercial buildings from DER CAM?s suggested investments is 17percent, while in Chinese buildings is 12percent. The electricity tariffs structure and prices along with the cost of natural gas, represent important factors in determining adoption of DER, more so than climate. High energy pricing spark spreads lead to increased economic attractiveness of DER. The average emissions reduction in commercial buildings is 19percent in the U.S. as a result of significant investments in PV, whereas in China, it is 20percent and driven by investments in CHP. Keywords: Building Modeling and Simulation, Distributed Energy Resources (DER), Energy Efficiency, Combined Heat and Power (CHP), CO2 emissions 1. Introduction The transition from a centralized and fossil-based energy paradigm towards the decentralization of energy supply and distribution has been a major subject of research over the past two decades. Various concerns have brought the traditional model into question; namely its environmental footprint, its structural inflexibility and inefficiency, and more recently, its inability to maintain acceptable reliability of supply. Under such a troubled setting, distributed energy resources (DER) comprising of small, modular, electrical renewable or fossil-based electricity generation units placed at or near the point of energy consumption, has gained much attention as a viable alternative or addition to the current energy system. In 2010, China consumed about 30percent of its primary energy in the buildings sector, leading the country to pay great attention to DER development and its applications in buildings. During the 11th Five Year Plan (FYP), China has implemented 371 renewable energy building demonstration projects, and 210 photovoltaics (PV) building integration projects. At the end of the 12th FYP, China is targeting renewable energy to provide 10percent of total building energy, and to save 30 metric tons of CO2 equivalents (mtce) of energy with building integrated renewables. China is also planning to implement one thousand natural gas-based distributed cogeneration demonstration projects with energy utilization rates over 70percent in the 12th FYP. All these policy targets require significant DER systems development for building applications. China?s fast urbanization makes building energy efficiency a crucial economic issue; however, only limited studies have been done that examine how to design and select suitable building energy technologies in its different regions. In the U.S., buildings consumed 40percent of the total primary energy in 2010 [1] and it is estimated that about 14 billion m2 of floor space of the existing building stock will be remodeled over the next 30 years. Most building?s renovation work has been on building envelope, lighting and HVAC systems. Although interest has emerged, less attention is being paid to DER for buildings. This context has created opportunities for research, development and progressive deployment of DER, due to its potential to combine the production of power and heat (CHP) near the point of consumption and delivering multiple benefits to customers, such as cost

  16. Study of Cherenkov Light Lateral Distribution Function around the Knee Region in Extensive Air Showers

    E-Print Network [OSTI]

    A. A. Al-Rubaiee; U. Hashim; Marwah M.; Y. Al-Douri

    2015-05-06T23:59:59.000Z

    The Cherenkov light lateral distribution function (LDF) was simulated with the CORSIKA code, in the energy range (10^13-10^16) eV. This simulation was performed for conditions and configurations of the Tunka EAS Cherenkov array for two primary particles (p and Fe). Basing on the simulated results, many approximated functions are structured for two primary particles and different zenith angles. This allowed us to reconstruct the EAS events, which is, to determine the type and energy of the primary particles that produced showers from signal amplitudes of Cherenkov radiation which measured with Tunka Cherenkov array experiment. Comparison of the calculated LDF of Cherenkov radiation with that measured at the Tunka EAS array shows the ability for identifying of the primary particle that initiated the EAS cascades determining of its primary energy around the knee region of the cosmic ray spectrum.

  17. 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.

  18. Resolving distribution of relaxation times in Poly(propylene glycol) on the crossover region

    E-Print Network [OSTI]

    Enis Tuncer; Marizio Furlani; Bengt-Erik Mellander

    2004-03-09T23:59:59.000Z

    In this paper, a recently developed numerical technique [{\\em Tuncer E and Guba{\\'n}ski S M, IEEE Trans Diel El Insul {\\bf 8}(3)(2001) 310-320}] is applied to poly(propylene glycol) complex dielectric data to extract more information about the molecular relaxation processes. The method is based on a constrained-least-squares (\\clsq) data fitting procedure together with the Monte Carlo (\\mc) method. We preselect the number of relaxation times with no {\\em a-priori} physical assumption, and use the Debye single relaxation as ``kernel'', then the obtained weighting factors at each \\mc step from the \\clsq method builds up a relaxation time spectrum. When the analysis is repeated for data at different temperatures a {\\em relaxation-image} is created. The obtained relaxation are analyzed using the Lorentz (Cauchy) distribution, which is a special form of the L{\\'e}vy statistics. In the present report the $\\beta$ and $\\alpha$ relaxations are resolved for the \\ppg. A comparison of the relaxations to those earlier reported in the literature indicate that the presented method provides additional information compared to methods based on empirical formulas. The distribution of relaxation times analysis is especially useful to probe the crossover region where the $\\alpha$- and $\\beta$- relaxations merge and the results show that the relaxation after the crossover region at higher temperatures is Arrhenius-type as the $\\beta$-relaxation. Moreover, this relaxation is more likely to be the continuation of the $\\beta$-relaxation, but with a different activation energy.

  19. 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.

  20. Interactive Distributed Ray Tracing of Highly Complex Models

    E-Print Network [OSTI]

    Wald, Ingo

    projects dealing with entire cars, ships, buildings, and processing plants. The complexity of such modelsInteractive Distributed Ray Tracing of Highly Complex Models Ingo Wald, Philipp Slusallek, Carsten- ulation of huge and complex 3D environments. Examples include large structural and mechanical engineering

  1. Modeling distributed generation in the buildings sectors

    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. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. William Hirst HirstModelingAssessing the

  2. Quark Wigner distributions in a light-cone spectator model

    E-Print Network [OSTI]

    Liu, Tianbo

    2015-01-01T23:59:59.000Z

    We investigate the quark Wigner distributions in a light-cone spectator model. The Wigner distribution, as a quasi-distribution function, provides the most general one-parton information in a hadron. Combining the polarization configurations, unpolarized, longitudinal polarized or transversal polarized, of the quark and the proton, we can define 16 independent Wigner distributions at leading twist. We calculate all these Wigner distributions for the $u$ quark and the $d$ quark respectively. In our calculation, both the scalar and the axial-vector spectators are included, and the Melosh-Wigner rotation effects for both the quark and the axial-vector spectator are taken into account. The results provide us a very rich picture of the quark structure in the proton.

  3. 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.

  4. Modeling and forecasting the distribution of Vibrio vulnificus in Chesapeake Bay

    SciTech Connect (OSTI)

    Jacobs, John M.; Rhodes, M.; Brown, C. W.; Hood, Raleigh R.; Leight, A.; Long, Wen; Wood, R.

    2014-11-01T23:59:59.000Z

    The aim is to construct statistical models to predict the presence, abundance and potential virulence of Vibrio vulnificus in surface waters. A variety of statistical techniques were used in concert to identify water quality parameters associated with V. vulnificus presence, abundance and virulence markers in the interest of developing strong predictive models for use in regional oceanographic modeling systems. A suite of models are provided to represent the best model fit and alternatives using environmental variables that allow them to be put to immediate use in current ecological forecasting efforts. Conclusions: Environmental parameters such as temperature, salinity and turbidity are capable of accurately predicting abundance and distribution of V. vulnificus in Chesapeake Bay. Forcing these empirical models with output from ocean modeling systems allows for spatially explicit forecasts for up to 48 h in the future. This study uses one of the largest data sets compiled to model Vibrio in an estuary, enhances our understanding of environmental correlates with abundance, distribution and presence of potentially virulent strains and offers a method to forecast these pathogens that may be replicated in other regions.

  5. Evaluating Equality using Parametric Income Distribution Models An exploration of alternative effects using a Dagum Parametric Income Distribution Model

    E-Print Network [OSTI]

    Ortega, Esther Ruiz

    to the study of income policy effects on the distribution of personal income. A parametric model of the Dagum on income data from several countries: Canada, the United States, Italy and Argentina. Therefore, the model and increased unemployment in most of the developed as well as developing countries. For policy- makers

  6. Modeling highway travel time distribution with conditional probability models

    SciTech Connect (OSTI)

    Oliveira Neto, Francisco Moraes [ORNL] [ORNL; Chin, Shih-Miao [ORNL] [ORNL; Hwang, Ho-Ling [ORNL] [ORNL; Han, Lee [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK)

    2014-01-01T23:59:59.000Z

    ABSTRACT Under the sponsorship of the Federal Highway Administration's Office of Freight Management and Operations, the American Transportation Research Institute (ATRI) has developed performance measures through the Freight Performance Measures (FPM) initiative. Under this program, travel speed information is derived from data collected using wireless based global positioning systems. These telemetric data systems are subscribed and used by trucking industry as an operations management tool. More than one telemetric operator submits their data dumps to ATRI on a regular basis. Each data transmission contains truck location, its travel time, and a clock time/date stamp. Data from the FPM program provides a unique opportunity for studying the upstream-downstream speed distributions at different locations, as well as different time of the day and day of the week. This research is focused on the stochastic nature of successive link travel speed data on the continental United States Interstates network. Specifically, a method to estimate route probability distributions of travel time is proposed. This method uses the concepts of convolution of probability distributions and bivariate, link-to-link, conditional probability to estimate the expected distributions for the route travel time. Major contribution of this study is the consideration of speed correlation between upstream and downstream contiguous Interstate segments through conditional probability. The established conditional probability distributions, between successive segments, can be used to provide travel time reliability measures. This study also suggests an adaptive method for calculating and updating route travel time distribution as new data or information is added. This methodology can be useful to estimate performance measures as required by the recent Moving Ahead for Progress in the 21st Century Act (MAP 21).

  7. 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.

  8. Modeling the formation and size distribution of fly ash

    SciTech Connect (OSTI)

    Dahlin, R.S.

    1985-01-01T23:59:59.000Z

    A set of mathematical models has been developed to predict the size distribution of fly ash particles formed in pulverized coal combustion. The large particle mode of the size distribution, typically centered about 10 to 20 ..mu..m, is predicted by a simple breakup model that is based on the complete coalescence of molten mineral inclusions within fragments of the devolatilized coal char. The ultrafine particle mode, that is typically centered about 0.1 to 0.2 ..mu..m, is modeled in terms of ash volatilization, nucleation, and coagulation. Silica and alumina are reduced to volatile suboxides through reactions at the char surface. The volatile suboxides are transported from the char surface where they are oxidized back to the stable oxides in the bulk gas, and then nucleated in accordance with homogeneous nucleation theory. The ultrafine nuclei coagulate in accordance with Brownian coagulation theory. The predicted particle size spectra have been compared to measured size distributions from a pilot-scale combustor and a full-scale utility boiler. Considering the disproportionate loss of coarse particles in the pilot-scale unit, the agreement between the predicted and measured size distributions was considered reasonably good. Both the predicted ultrafine and large particle modes agreed reasonably well with the measured particle size distribution for the full scale boiler. The validated computer models were used to study the effect of changes in the coal ash content, coal particle size, and the combustion flame temperature.

  9. 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.

  10. Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

    SciTech Connect (OSTI)

    NONE

    1996-02-26T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.

  11. 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, ...

  12. Probability distributions for regional climate change from uncertain global mean warming and uncertain scaling relationship Hydrol. Earth Syst. Sci., 11(3), 10971114, 2007

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Probability distributions for regional climate change from uncertain global mean warming of probability distributions for regional climate change from uncertain global mean warming and an uncertain/precipitation per degree global mean warming. Each scaling variable is assumed to be normally distributed

  13. 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.

  14. 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).

  15. 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.

  16. Model documentation: Natural Gas Transmission and Distribution Model of the National Energy Modeling System; Volume 1

    SciTech Connect (OSTI)

    NONE

    1994-02-24T23:59:59.000Z

    The Natural Gas Transmission and Distribution Model (NGTDM) is a component of the National Energy Modeling System (NEMS) used to represent the domestic natural gas transmission and distribution system. NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the Energy Information Administration (EIA) and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. This report documents the archived version of NGTDM that was used to produce the natural gas forecasts used in support of the Annual Energy Outlook 1994, DOE/EIA-0383(94). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. It is intended to fulfill the legal obligation of the EIA to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). This report represents Volume 1 of a two-volume set. (Volume 2 will report on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.) Subsequent chapters of this report provide: (1) an overview of the NGTDM (Chapter 2); (2) a description of the interface between the National Energy Modeling System (NEMS) and the NGTDM (Chapter 3); (3) an overview of the solution methodology of the NGTDM (Chapter 4); (4) the solution methodology for the Annual Flow Module (Chapter 5); (5) the solution methodology for the Distributor Tariff Module (Chapter 6); (6) the solution methodology for the Capacity Expansion Module (Chapter 7); (7) the solution methodology for the Pipeline Tariff Module (Chapter 8); and (8) a description of model assumptions, inputs, and outputs (Chapter 9).

  17. An Impact Assessment Model for Distributed Adaptive Security Situation Assessment*

    E-Print Network [OSTI]

    California at Davis, University of

    1 An Impact Assessment Model for Distributed Adaptive Security Situation Assessment* Mark Heckman mechanism is not simply to stop attacks, but to protect a computing resource so that the resource can continue to perform its function. A computing resource, however, is only a component of a larger system

  18. Cloud vertical distribution from radiosonde, remote sensing, and model simulations

    E-Print Network [OSTI]

    Li, Zhanqing

    Cloud vertical distribution from radiosonde, remote sensing, and model simulations Jinqiang Zhang's radiation budget and atmospheric adiabatic heating. Yet it is among the most difficult quantities to observe Great Plains and along with ground- based and space-borne remote sensing products, use it to evaluate

  19. LIMITED POWER BURSTS IN DISTRIBUTED MODELS OF NUCLEAR REACTORS

    E-Print Network [OSTI]

    Bazhenov, Maxim

    LIMITED POWER BURSTS IN DISTRIBUTED MODELS OF NUCLEAR REACTORS M. V. Bazhenov and E. F. Sabaev UDC employed for analyzing reactor dynamics. Equations of this type are used for analyzing the stability of the reactor power, etc. Among these problems the question of the boundedness of reactor power bursts

  20. High Resolution PV Power Modeling for Distribution Circuit Analysis

    SciTech Connect (OSTI)

    Norris, B. L.; Dise, J. H.

    2013-09-01T23:59:59.000Z

    NREL has contracted with Clean Power Research to provide 1-minute simulation datasets of PV systems located at three high penetration distribution feeders in the service territory of Southern California Edison (SCE): Porterville, Palmdale, and Fontana, California. The resulting PV simulations will be used to separately model the electrical circuits to determine the impacts of PV on circuit operations.

  1. Can remote sensing of land cover improve species distribution modelling?

    E-Print Network [OSTI]

    Bradley, Bethany

    COMMENTARY Can remote sensing of land cover improve species distribution modelling? Remote sensing- guish among broad classes of vegetation. However, the applicability of remote sensing to classification like from remote sensing ­ a map of tree species ­ and what can be delivered ­ a map of forest types

  2. Physical Modeling of Scaled Water Distribution System Networks.

    SciTech Connect (OSTI)

    O'Hern, Timothy J.; Hammond, Glenn Edward; Orear, Leslie ,; van Bloemen Waanders, Bart G.; Paul Molina; Ross Johnson

    2005-10-01T23:59:59.000Z

    Threats to water distribution systems include release of contaminants and Denial of Service (DoS) attacks. A better understanding, and validated computational models, of the flow in water distribution systems would enable determination of sensor placement in real water distribution networks, allow source identification, and guide mitigation/minimization efforts. Validation data are needed to evaluate numerical models of network operations. Some data can be acquired in real-world tests, but these are limited by 1) unknown demand, 2) lack of repeatability, 3) too many sources of uncertainty (demand, friction factors, etc.), and 4) expense. In addition, real-world tests have limited numbers of network access points. A scale-model water distribution system was fabricated, and validation data were acquired over a range of flow (demand) conditions. Standard operating variables included system layout, demand at various nodes in the system, and pressure drop across various pipe sections. In addition, the location of contaminant (salt or dye) introduction was varied. Measurements of pressure, flowrate, and concentration at a large number of points, and overall visualization of dye transport through the flow network were completed. Scale-up issues that that were incorporated in the experiment design include Reynolds number, pressure drop across nodes, and pipe friction and roughness. The scale was chosen to be 20:1, so the 10 inch main was modeled with a 0.5 inch pipe in the physical model. Controlled validation tracer tests were run to provide validation to flow and transport models, especially of the degree of mixing at pipe junctions. Results of the pipe mixing experiments showed large deviations from predicted behavior and these have a large impact on standard network operations models.3

  3. Predicting the Power Output of Distributed Renewable Energy Resources within a Broad Geographical Region

    E-Print Network [OSTI]

    Chalkiadakis, Georgios

    Predicting the Power Output of Distributed Renewable Energy Resources within a Broad Geographical potentially dis- tributed renewable energy resources (su years, estimating the power output of in- herently intermittent and potentially distributed renewable

  4. 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

  5. Abstract A model of "distributed cognition" is con-trasted with the "mental representation" model exempli-

    E-Print Network [OSTI]

    Kirsh, David

    of human cognition. By the same token, however, T&C's use of the MR model subjects their efforts to a setAbstract A model of "distributed cognition" is con- trasted with the "mental representation" model, this model characterizes cognition as "co-con- structed" by the participants. This approach is thus partic

  6. Effects of the Tsallis distribution in the linear sigma model

    E-Print Network [OSTI]

    Masamichi Ishihara

    2015-04-11T23:59:59.000Z

    The effects of the Tsallis distribution which has two parameters, $q$ and $T$,on physical quantities are studied using the linear sigma model in chiral phase transitions.The parameter $T$ dependences of the condensate and mass for various $q$ are shown, where $T$ is called temperature. The Tsallis distribution approaches the Boltzmann-Gibbs distribution as $q$ approaches $1$. The critical temperature and energy density are described with digamma function, and the $q$ dependences of these quantities and the extension of Stefan-Boltzmann limit of the energy density are shown. The following facts are clarified. The chiral symmetry restoration for $q>1$ occurs at low temperature, compared with the restoration at $q=1$. The sigma mass and pion mass reflect the restoration. The critical temperature decreases monotonically as $q$ increases. The small deviation from the Boltzmann-Gibbs distribution results in the large deviations of physical quantities, especially the energy density. It is displayed from the energetic point of view that the small deviation from the Boltzmann-Gibbs distribution is realized for $q>1$. The physical quantities are affected by the Tsallis distribution even when $|q-1|$ is small.

  7. Pit distribution in the equatorial region of Titan Kimberly A. Adams n

    E-Print Network [OSTI]

    Jurdy, Donna M.

    distribution and size to characterize these features and understand their formation. Chi-square analysis. However, analysis of the densest cluster of pits, a group of 50, shows a more random distribution. Fractal analysis and comparison with a same-sized random set find only a hint of linearity. A Poisson distribution

  8. Mechanistic model for void distribution in flashing flow

    SciTech Connect (OSTI)

    Riznic, J.; Ishii, M.; Afgan, N.

    1987-01-01T23:59:59.000Z

    A problem of discharging of an initially subcooled liquid from a high pressure condition into a low pressure environment is quite important in several industrial systems such as nuclear reactors and chemical reactors. A new model for the flashing process is proposed here based on the wall nucleation theory, bubble growth model and drift-flux bubble transport model. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites is used. The model predictions in terms of the void fraction are compared to Moby Dick and BNL experimental data. It shows that satisfactory agreements could be obtained from the present model without any floating parameter to be adjusted with data. This result indicates that, at least for the experimental conditions considered here, the mechanistic prediction of the flashing phenomenon is possible based on the present wall nucleation based model. 43 refs., 4 figs.

  9. Ising Model on Networks with an Arbitrary Distribution of Connections

    E-Print Network [OSTI]

    S. N. Dorogovtsev; A. V. Goltsev; J. F. F. Mendes

    2002-04-11T23:59:59.000Z

    We find the exact critical temperature $T_c$ of the nearest-neighbor ferromagnetic Ising model on an `equilibrium' random graph with an arbitrary degree distribution $P(k)$. We observe an anomalous behavior of the magnetization, magnetic susceptibility and specific heat, when $P(k)$ is fat-tailed, or, loosely speaking, when the fourth moment of the distribution diverges in infinite networks. When the second moment becomes divergent, $T_c$ approaches infinity, the phase transition is of infinite order, and size effect is anomalously strong.

  10. 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.

  11. 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.

  12. 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

  13. The effects of practice distribution upon the regional oscillatory activity in visuomotor learning

    E-Print Network [OSTI]

    Studer, Bettina; Koeneke, Susan; Blum, Julia; Jancke, Lutz

    2010-01-22T23:59:59.000Z

    , provided the original work is properly cited. motor learning. So far, explanations of the proposed superiority of distributed practice schedules were pri- marily based on practical considerations (e.g. attention demands, fatigue). The neural underpinnings... an explanation for this incon- sistency with the findings of most previous studies. The superiority of distributed over massed practice has pre- dominately been shown in simple motor tasks in which the temporal distribution of training sessions led to bet- ter...

  14. A U.S. and China Regional Analysis of Distributed Energy Resources in Buildings

    E-Print Network [OSTI]

    Feng, Wei

    2014-01-01T23:59:59.000Z

    www.epa.gov/cleanenergy/energy-resources/egrid. [24] Wang,Gas-Fired Distributed Energy Resource Characterizations.CO: National Renewable Energy Resource Laboratory Report TP-

  15. Time series models with an EGB2 conditional distribution

    E-Print Network [OSTI]

    Caivano, Michele; Harvey, Andrew

    2014-07-09T23:59:59.000Z

    was made by Wang et. al. (2001) who ?tted GARCH-EGB2 models to exchange rate data. The article is organized as follows. In Section 2, the DCS location model based on the general form of the EGB2 distribution, which allows for skew- ness, is introduced... of the location score, dividing (12) by #15;t gives a bounded function as j#15;tj ! 1: Note that the score function is often called the news-impact curve in the GARCH literature and that it becomes asymmetic when a leverage term is introduced into the dynamics...

  16. 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.

  17. Probabilistic graphical models : distributed inference and learning models with small feedback vertex sets

    E-Print Network [OSTI]

    Liu, Ying, Ph. D. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science

    2014-01-01T23:59:59.000Z

    In undirected graphical models, each node represents a random variable while the set of edges specifies the conditional independencies of the underlying distribution. When the random variables are jointly Gaussian, the ...

  18. Abstract--This paper presents the impact of different types of load models in distribution network with distributed wind

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    as a major enabler of the smart grid for the integration of small and medium sized renewable energy based that modeling of loads has a significant impact on the voltage dynamics of the distribution systemAbstract--This paper presents the impact of different types of load models in distribution network

  19. Concerning effects of low-beta region fringe fields and multipole error distribution on dynamics in LHC.

    SciTech Connect (OSTI)

    Meot, F.; Paris, A.

    1997-08-01T23:59:59.000Z

    Effects of fringe fields in separation dipoles D1/D2 and low-{beta} quadrupoles Q1-Q3 of LHC interaction regions in collision optics are investigated by means of stepwise ray-tracing in terms of aberrations, beam envelopes and other detunings. Effects of the longitudinal distribution of b{sub 10} error coefficient are next investigated in a similar way for assessment and comparison.

  20. Probe measurements and numerical model predictions of evolving size distributions in premixed flames

    SciTech Connect (OSTI)

    De Filippo, A.; Sgro, L.A.; Lanzuolo, G.; D'Alessio, A. [Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli (Italy)

    2009-09-15T23:59:59.000Z

    Particle size distributions (PSDs), measured with a dilution probe and a Differential Mobility Analyzer (DMA), and numerical predictions of these PSDs, based on a model that includes only coagulation or alternatively inception and coagulation, are compared to investigate particle growth processes and possible sampling artifacts in the post-flame region of a C/O = 0.65 premixed laminar ethylene-air flame. Inputs to the numerical model are the PSD measured early in the flame (the initial condition for the aerosol population) and the temperature profile measured along the flame's axial centerline. The measured PSDs are initially unimodal, with a modal mobility diameter of 2.2 nm, and become bimodal later in the post-flame region. The smaller mode is best predicted with a size-dependent coagulation model, which allows some fraction of the smallest particles to escape collisions without resulting in coalescence or coagulation through the size-dependent coagulation efficiency ({gamma}{sub SD}). Instead, when {gamma} = 1 and the coagulation rate is equal to the collision rate for all particles regardless of their size, the coagulation model significantly under predicts the number concentration of both modes and over predicts the size of the largest particles in the distribution compared to the measured size distributions at various heights above the burner. The coagulation ({gamma}{sub SD}) model alone is unable to reproduce well the larger particle mode (mode II). Combining persistent nucleation with size-dependent coagulation brings the predicted PSDs to within experimental error of the measurements, which seems to suggest that surface growth processes are relatively insignificant in these flames. Shifting measured PSDs a few mm closer to the burner surface, generally adopted to correct for probe perturbations, does not produce a better matching between the experimental and the numerical results. (author)

  1. 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

  2. HII regions in spiral galaxies: Size distribution, luminosity function, and new isochrone diagnostics of density wave kinematics

    E-Print Network [OSTI]

    M. S. Oey; J. S. Parker; V. J. Mikles; X. Zhang

    2003-07-10T23:59:59.000Z

    We investigate the relationship of the HII region luminosity function (HII LF) to the HII region size distribution and density wave triggering in grand-design spiral galaxies. We suggest that the differential nebular size distribution is described by a power law of slope ~ -4, with flattening at radii below ~ 130 pc. This contrasts with the conventional exponential description, but it is physically and quantitatively consistent with the typical observed value of -2 for the HII LF slope. We have developed an interactive code that computes spatial isochrones for the evolving loci of spiral density waves in disk galaxies. This allows comparison of the nebular spatial distribution with the spatial isochrones for simple rotation curve parameters. Our comparisons for four grand-design galaxies suggest that the corotation radius r_co coincides with the outer ends of the star-forming arms. This value for r_co yields the best spatial correspondence between the HII regions and the isochrones, and also appears to yield a coincidence between the Inner Lindblad Resonance with the radial onset of star formation in the arms. Thus, we suggest that isochrones offer a new, simple, and effective technique for determining r_co, and thus the spiral pattern speed. However, application of the isochrones also demonstrates that evolution of the nebular population is difficult to spatially isolate in these galaxies.

  3. 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.

  4. Spatial Distribution Of Cs-137 In Surface Soils On Some Central Rhodopes Regions

    SciTech Connect (OSTI)

    Hristov, Hr. G.; Srentz, A. K.; Balabanov, N. P. [Plovdiv University, 24 Tzar Assen Str., 4000 Plovdiv (Bulgaria)

    2007-04-23T23:59:59.000Z

    The subject of investigation are soils from region around village Kiselchovo, town Smolyan, villages Narechen, Bachkovo, Laki, Kosovo, Dobralak, Central Rhodopes region. The samples have been collected from natural soils at a depth of 0-10 cm. The samples have been analyzed for the content of technogenical radionuclide Cs-137. The measurements were taken by precise gamma ray spectrometer. Based on the conducted research an inference can be made that there are radioactive contamination (up to 30 times over the background level)

  5. Development of Distributed Programming Developing Tool-Kit Based on Object Group Model

    E-Print Network [OSTI]

    Joo, Su-Chong

    Development of Distributed Programming Developing Tool-Kit Based on Object Group Model Jeong of the grouped distributed objects[10-14], as a logical unit of distributed application service, and developed a distributed programming developing tool-kit based on object group model(OGM-DPD Tool-Kit). This Tool- Kit can

  6. Feasible Distributed CSP Models for Scheduling Problems Miguel A. Salido, Adriana Giret

    E-Print Network [OSTI]

    Salido, Miguel Angel

    Feasible Distributed CSP Models for Scheduling Problems Miguel A. Salido, Adriana Giret Universidad satisfaction problem (DisCSP) is a CSP in which variables and constraints are distributed among multiple are distributed by using our model. Key words: distributed CSP, constraint satisfaction, holonic system, multi

  7. Calibration of a Distributed Flood Forecasting Model with Input Uncertainty Using a Bayesian Framework

    E-Print Network [OSTI]

    Hubbard, Susan

    Calibration of a Distributed Flood Forecasting Model with Input Uncertainty Using a Bayesian, Berkeley, CA, United States. In the process of calibrating distributed hydrological models, accounting in calibrating GBHM parameters and in estimating their associated uncertainty. The calibration ignoring input

  8. 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

  9. 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

  10. Modeling of customer adoption of distributed energy resources

    SciTech Connect (OSTI)

    Marnay, Chris; Chard, Joseph S.; Hamachi, Kristina S.; Lipman, Timothy; Moezzi, Mithra M.; Ouaglal, Boubekeur; Siddiqui, Afzal S.

    2001-08-01T23:59:59.000Z

    This report describes work completed for the California Energy Commission (CEC) on the continued development and application of the Distributed Energy Resources Customer Adoption Model (DER-CAM). This work was performed at Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) between July 2000 and June 2001 under the Consortium for Electric Reliability Technology Solutions (CERTS) Distributed Energy Resources Integration (DERI) project. Our research on distributed energy resources (DER) builds on the concept of the microgrid ({mu}Grid), a semiautonomous grouping of electricity-generating sources and end-use sinks that are placed and operated for the benefit of its members. Although a {mu}Grid can operate independent of the macrogrid (the utility power network), the {mu}Grid is usually interconnected, purchasing energy and ancillary services from the macrogrid. Groups of customers can be aggregated into {mu}Grids by pooling their electrical and other loads, and the most cost-effective combination of generation resources for a particular {mu}Grid can be found. In this study, DER-CAM, an economic model of customer DER adoption implemented in the General Algebraic Modeling System (GAMS) optimization software is used, to find the cost-minimizing combination of on-site generation customers (individual businesses and a {mu}Grid) in a specified test year. DER-CAM's objective is to minimize the cost of supplying electricity to a specific customer by optimizing the installation of distributed generation and the self-generation of part or all of its electricity. Currently, the model only considers electrical loads, but combined heat and power (CHP) analysis capability is being developed under the second year of CEC funding. The key accomplishments of this year's work were the acquisition of increasingly accurate data on DER technologies, including the development of methods for forecasting cost reductions for these technologies, and the creation of a credible example California {mu}Grid for use in this study and in future work. The work performed during this year demonstrates the viability of DER-CAM and of our approach to analyzing adoption of DER.

  11. Modeling Experts and Novices in Citizen Science Data for Species Distribution Modeling

    E-Print Network [OSTI]

    Modeling Experts and Novices in Citizen Science Data for Species Distribution Modeling Jun Yu, Weng-habitat relationships, is a research area that can benefit greatly from citizen science. The eBird project [18] is one of the largest citizen science programs in existence. By allowing birders to upload ob- servations of bird

  12. Geophysical constraints on the surface distribution of authigenic carbonates across the Hydrate Ridge region,

    E-Print Network [OSTI]

    Goldfinger, Chris

    the shallow source of methane and water contained in subsurface and surface gas hydrates. The distribution hemipelagic sediment. Hydrate Ridge lies within the gas hydrate stability field offshore central Oregon and during the last 15 years several studies have documented gas hydrate and cold seep carbonate occurrence

  13. The cosmic ray primary composition at the knee region from lateral distributions of atmospheric C

    E-Print Network [OSTI]

    -8530, Japan g Instituto de Investigaciones Fisicas, Universidad Mayor de San Andres, La Paz 8635, Bolivia h in the energy range from 1014.5 to 1016 eV, so called knee region. The atmospheric C erenkov photon detectors. Introduction The energy spectrum of cosmic rays is expressed by power law in the wide energy range from 1010

  14. Joint physical and numerical modeling of water distribution networks.

    SciTech Connect (OSTI)

    Zimmerman, Adam; O'Hern, Timothy John; Orear, Leslie Jr.; Kajder, Karen C.; Webb, Stephen Walter; Cappelle, Malynda A.; Khalsa, Siri Sahib; Wright, Jerome L.; Sun, Amy Cha-Tien; Chwirka, J. Benjamin; Hartenberger, Joel David; McKenna, Sean Andrew; van Bloemen Waanders, Bart Gustaaf; McGrath, Lucas K.; Ho, Clifford Kuofei

    2009-01-01T23:59:59.000Z

    This report summarizes the experimental and modeling effort undertaken to understand solute mixing in a water distribution network conducted during the last year of a 3-year project. The experimental effort involves measurement of extent of mixing within different configurations of pipe networks, measurement of dynamic mixing in a single mixing tank, and measurement of dynamic solute mixing in a combined network-tank configuration. High resolution analysis of turbulence mixing is carried out via high speed photography as well as 3D finite-volume based Large Eddy Simulation turbulence models. Macroscopic mixing rules based on flow momentum balance are also explored, and in some cases, implemented in EPANET. A new version EPANET code was developed to yield better mixing predictions. The impact of a storage tank on pipe mixing in a combined pipe-tank network during diurnal fill-and-drain cycles is assessed. Preliminary comparison between dynamic pilot data and EPANET-BAM is also reported.

  15. 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...

  16. 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

  17. Effects of head-up tilt on mean arterial pressure, heart rate, and regional cardiac output distribution in aging rats

    E-Print Network [OSTI]

    Ramsey, Michael Wiechmann

    2006-04-12T23:59:59.000Z

    on Mean Arterial Pressure, Heart Rate, and Regional Cardiac Output Distribution in Aging Rats. (December 2005) Michael Wiechmann Ramsey, B.S.; M.A., Sam Houston State University Chair of Advisory Committee: Dr. Michael Delp Many senescent... to extend my gratitude to my friends as well as the faculty and staff that have supported me throughout my studies at Texas A&M University. Thanks also to Dr. Gary Oden who helped instill a love and appreciation of Exercise Physiology. A special thanks...

  18. Modeling of customer adoption of distributed energy resources

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    of Dispersed Energy Resources Deployment. Berkeley, LawrenceAdoption of Distributed Energy Resources Ozbek, A. 2001.Adoption of Distributed Energy Resources Figure 39. Figure

  19. Distributed generation capabilities of the national energy modeling system

    SciTech Connect (OSTI)

    LaCommare, Kristina Hamachi; Edwards, Jennifer L.; Marnay, Chris

    2003-01-01T23:59:59.000Z

    This report describes Berkeley Lab's exploration of how the National Energy Modeling System (NEMS) models distributed generation (DG) and presents possible approaches for improving how DG is modeled. The on-site electric generation capability has been available since the AEO2000 version of NEMS. Berkeley Lab has previously completed research on distributed energy resources (DER) adoption at individual sites and has developed a DER Customer Adoption Model called DER-CAM. Given interest in this area, Berkeley Lab set out to understand how NEMS models small-scale on-site generation to assess how adequately DG is treated in NEMS, and to propose improvements or alternatives. The goal is to determine how well NEMS models the factors influencing DG adoption and to consider alternatives to the current approach. Most small-scale DG adoption takes place in the residential and commercial modules of NEMS. Investment in DG ultimately offsets purchases of electricity, which also eliminates the losses associated with transmission and distribution (T&D). If the DG technology that is chosen is photovoltaics (PV), NEMS assumes renewable energy consumption replaces the energy input to electric generators. If the DG technology is fuel consuming, consumption of fuel in the electric utility sector is replaced by residential or commercial fuel consumption. The waste heat generated from thermal technologies can be used to offset the water heating and space heating energy uses, but there is no thermally activated cooling capability. This study consists of a review of model documentation and a paper by EIA staff, a series of sensitivity runs performed by Berkeley Lab that exercise selected DG parameters in the AEO2002 version of NEMS, and a scoping effort of possible enhancements and alternatives to NEMS current DG capabilities. In general, the treatment of DG in NEMS is rudimentary. The penetration of DG is determined by an economic cash-flow analysis that determines adoption based on the n umber of years to a positive cash flow. Some important technologies, e.g. thermally activated cooling, are absent, and ceilings on DG adoption are determined by some what arbitrary caps on the number of buildings that can adopt DG. These caps are particularly severe for existing buildings, where the maximum penetration for any one technology is 0.25 percent. On the other hand, competition among technologies is not fully considered, and this may result in double-counting for certain applications. A series of sensitivity runs show greater penetration with net metering enhancements and aggressive tax credits and a more limited response to lowered DG technology costs. Discussion of alternatives to the current code is presented in Section 4. Alternatives or improvements to how DG is modeled in NEMS cover three basic areas: expanding on the existing total market for DG both by changing existing parameters in NEMS and by adding new capabilities, such as for missing technologies; enhancing the cash flow analysis but incorporating aspects of DG economics that are not currently represented, e.g. complex tariffs; and using an external geographic information system (GIS) driven analysis that can better and more intuitively identify niche markets.

  20. 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.

  1. 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

  2. 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.

  3. Distribution of Soil Temperature Regimes and Climate Change in the Mojave Desert Region

    E-Print Network [OSTI]

    Bai, Yanying

    2009-01-01T23:59:59.000Z

    precipitation, and water vapor on diurnal temperature range.Idaho, United States. Water Resour. Res. 37: 2843-2846.and J. Bouma. 1994. Modelling water and chemical fluxes as

  4. DSE Perspective on QCD Modeling, Distribution Amplitudes, and Form Factors

    E-Print Network [OSTI]

    Peter C Tandy

    2014-07-02T23:59:59.000Z

    We describe results for the pion distribution amplitude (PDA) at the non-perturbative scale $\\mu=~$2GeV by projecting the Poincar\\'e-covariant Bethe-Salpeter wave-function onto the light-front and use it to investigate the ultraviolet behavior of the electromagnetic form factor, $F_\\pi(Q^2)$, on the entire domain of spacelike $Q^2$. The significant dilation of this PDA compared to the known asymptotic PDA is a signature of dynamical chiral symmetry breaking (DCSB) on the light front. We investigate the transition region of $Q^2$ where non-perturbative behavior of constituent-like quarks gives way to the partonic-like behavior of quantum chromodynamics (QCD). The non-perturbative approach is based on the Dyson-Schwinger equation (DSE) framework for continuum investigations in QCD. The leading-order, leading-twist perturbative QCD result for $Q^2 F_\\pi(Q^2)$ underestimates the new DSE computation by just 15\\% on $Q^2\\gtrsim 8\\,$GeV$^2$, in stark contrast with the result obtained using the asymptotic PDA.

  5. 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,.

  6. 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

  7. MODELS FOR THE DISTRIBUTION OF QUAKING ASPEN IN GEOGRAPHIC AND POTENTIAL EVAPOTRANSPIRATION SPACES RELEVANT TO

    E-Print Network [OSTI]

    Ramsey, R. Douglas

    MODELS FOR THE DISTRIBUTION OF QUAKING ASPEN IN GEOGRAPHIC AND POTENTIAL EVAPOTRANSPIRATION SPACES Models for the distribution of quaking aspen concentration in geographic and potential evapotranspiration, and Wildlife Sciences Quaking aspen is the most widely distributed tree species in North America and an asset

  8. Fine scale modeling of wintertime aerosol mass, number, and size distributions in central California

    E-Print Network [OSTI]

    Jacobson, Mark

    Fine scale modeling of wintertime aerosol mass, number, and size distributions in central with the observed PM number and size distributions (with an NMB of -13.9%), indicating the importance of coagulation scale modeling of wintertime aerosol mass, number, and size distributions in central California, J

  9. MODELING THE ATOMIC-TO-MOLECULAR TRANSITION AND CHEMICAL DISTRIBUTIONS OF TURBULENT STAR-FORMING CLOUDS

    SciTech Connect (OSTI)

    Offner, Stella S. R. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Bisbas, Thomas G.; Viti, Serena [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6B (United Kingdom); Bell, Tom A., E-mail: stella.offner@yale.edu [Centro de Astrobiologia (CSIC-INTA), Carretera de Ajalvir, km 4, E-28850 Madrid (Spain)

    2013-06-10T23:59:59.000Z

    We use 3D-PDR, a three-dimensional astrochemistry code for modeling photodissociation regions (PDRs), to post-process hydrodynamic simulations of turbulent, star-forming clouds. We focus on the transition from atomic to molecular gas, with specific attention to the formation and distribution of H, C{sup +}, C, H{sub 2}, and CO. First, we demonstrate that the details of the cloud chemistry and our conclusions are insensitive to the simulation spatial resolution, to the resolution at the cloud edge, and to the ray angular resolution. We then investigate the effect of geometry and simulation parameters on chemical abundances and find weak dependence on cloud morphology as dictated by gravity and turbulent Mach number. For a uniform external radiation field, we find similar distributions to those derived using a one-dimensional PDR code. However, we demonstrate that a three-dimensional treatment is necessary for a spatially varying external field, and we caution against using one-dimensional treatments for non-symmetric problems. We compare our results with the work of Glover et al., who self-consistently followed the time evolution of molecule formation in hydrodynamic simulations using a reduced chemical network. In general, we find good agreement with this in situ approach for C and CO abundances. However, the temperature and H{sub 2} abundances are discrepant in the boundary regions (A{sub v} {<=} 5), which is due to the different number of rays used by the two approaches.

  10. Simulated Global Atmospheric Dust Distribution: Sensitivity to Regional Topography, Geomorphology, and Hydrology

    E-Print Network [OSTI]

    Zender, Charles

    , and Hydrology Charles S. Zender, Earth System Science Dept., UC Irvine, Irvine, CA 92697 (zender@uci.edu) David for predicting future trends in dust production. We identify three related geomorphologic and hydrologic hydrologically disturbed/renewed sed- iments. Dust models which attempt to account for sediment-rich source

  11. 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

  12. Distributed Estimation in Sensor Networks with Modeling Uncertainty

    E-Print Network [OSTI]

    Zhou, Qing

    2013-05-07T23:59:59.000Z

    A major issue in distributed wireless sensor networks (WSNs) is the design of efficient distributed algorithms for network-wide dissemination of information acquired by individual sensors, where each sensor, by itself, is unable to access enough...

  13. On Models for Object Lifetime Distributions Darko Stefanovi c

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    ---memory management (garbage collection); G.3 [Mathematics of Computing]: Probability and Statistics---survival in salient shape characteristics with the gamma distribution family used in statistical survival analysis analysis General Terms Measurement Keywords Object lifetimes, lifetime distributions, garbage collection

  14. 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

  15. DAVE: A plug and play model for distributed multimedia application development

    SciTech Connect (OSTI)

    Mines, R.F.; Friesen, J.A.; Yang, C.L.

    1994-07-01T23:59:59.000Z

    This paper presents a model being used for the development of distributed multimedia applications. The Distributed Audio Video Environment (DAVE) was designed to support the development of a wide range of distributed applications. The implementation of this model is described. DAVE is unique in that it combines a simple ``plug and play`` programming interface, supports both centralized and fully distributed applications, provides device and media extensibility, promotes object reuseability, and supports interoperability and network independence. This model enables application developers to easily develop distributed multimedia applications and create reusable multimedia toolkits. DAVE was designed for developing applications such as video conferencing, media archival, remote process control, and distance learning.

  16. 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.

  17. Statistical Model Checking for Distributed Probabilistic-Control Hybrid Automata with

    E-Print Network [OSTI]

    Platzer, André

    Statistical Model Checking for Distributed Probabilistic-Control Hybrid Automata with Smart Grid accurately model real-world power consumption). We propose Distributed Probabilistic-Control Hybrid Automata and apply existing statistical model- checking techniques. We provide an implementation of a framework

  18. Using Citizen Science Data to Model the Distributions of Common Songbirds of Turkey Under Different Global

    E-Print Network [OSTI]

    Tipple, Brett

    Using Citizen Science Data to Model the Distributions of Common Songbirds of Turkey Under Different an ornithological citizen science initiative (www.kusbank.org) with maximum entropy modeling and eight bioclimatic (2013) Using Citizen Science Data to Model the Distributions of Common Songbirds of Turkey Under

  19. The Distribution of Loop Lengths in Graphical Models for Turbo Decoding

    E-Print Network [OSTI]

    Smyth, Padhraic

    1 The Distribution of Loop Lengths in Graphical Models for Turbo Decoding Xianping Ge, David model for a K = 6, N = 12, rate 1=2 turbo code. Abstract| This paper analyzes the distribution of loop lengths in graphical models for turbo decoding. The prop- erties of such loops are of signi#12;cant

  20. 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.

  1. Is the Weibull distribution really suited for wind statistics modeling and wind power evaluation?

    E-Print Network [OSTI]

    Drobinski, Philippe

    2012-01-01T23:59:59.000Z

    Wind speed statistics is generally modeled using the Weibull distribution. This distribution is convenient since it fully characterizes analytically with only two parameters (the shape and scale parameters) the shape of distribution and the different moments of the wind speed (mean, standard deviation, skewness and kurtosis). This distribution is broadly used in the wind energy sector to produce maps of wind energy potential. However, the Weibull distribution is based on empirical rather than physical justification and might display strong limitations for its applications. The philosophy of this article is based on the modeling of the wind components instead of the wind speed itself. This provides more physical insights on the validity domain of the Weibull distribution as a possible relevant model for wind statistics and the quantification of the error made by using such a distribution. We thereby propose alternative expressions of more suited wind speed distribution.

  2. Optimal Control of Distributed Energy Resources using Model Predictive Control

    SciTech Connect (OSTI)

    Mayhorn, Ebony T.; Kalsi, Karanjit; Elizondo, Marcelo A.; Zhang, Wei; Lu, Shuai; Samaan, Nader A.; Butler-Purry, Karen

    2012-07-22T23:59:59.000Z

    In an isolated power system (rural microgrid), Distributed Energy Resources (DERs) such as renewable energy resources (wind, solar), energy storage and demand response can be used to complement fossil fueled generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation. The problem is formulated as a multi-objective optimization problem with the goals of minimizing fuel costs and changes in power output of diesel generators, minimizing costs associated with low battery life of energy storage and maintaining system frequency at the nominal operating value. Two control modes are considered for controlling the energy storage to compensate either net load variability or wind variability. Model predictive control (MPC) is used to solve the aforementioned problem and the performance is compared to an open-loop look-ahead dispatch problem. Simulation studies using high and low wind profiles, as well as, different MPC prediction horizons demonstrate the efficacy of the closed-loop MPC in compensating for uncertainties in wind and demand.

  3. 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, ...

  4. 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, ...

  5. Distribution and kinematics of the HCN(3-2) emission down to the innermost region in the envelope of the O-rich star W Hya

    E-Print Network [OSTI]

    Muller Sebastien; Dinh-V-Trung; He Jin-Hua; Lim Jeremy

    2008-08-04T23:59:59.000Z

    We report high angular resolution observations of the HCN (3-2) line emission in the circumstellar envelope of the O-rich star W Hya with the Submillimeter Array. The proximity of this star allows us to image its molecular envelope with a spatial resolution of just ~40 AU, corresponding to about 10 times the stellar diameter. We resolve the HCN (3-2) emission and find that it is centrally peaked and has a roughly spherically symmetrical distribution. This shows that HCN is formed in the innermost region of the envelope (within ~10 stellar radii), which is consistent with predictions from pulsation-driven shock chemistry models, and rules out the scenario in which HCN forms through photochemical reactions in the outer envelope. Our model suggests that the envelope decreases steeply in temperature and increases smoothly in velocity with radius, inconsistent with the standard model for mass-loss driven by radiative pressure on dust grains. We detect a velocity gradient of ~5 km/s in the NW--SE direction over the central 40 AU. This velocity gradient is reminescent of that seen in OH maser lines, and could be caused by the rotation of the envelope or by a weak bipolar outflow.

  6. 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).

  7. Modeling and Generating Daily Changes in Market Variables Using A Multivariate Mixture of Normal Distributions

    E-Print Network [OSTI]

    Wang, Jin

    Distributions Jin Wang Department of Mathematics and Computer Science Valdosta State University Valdosta, GA 31698-0040 January 28, 2000 Abstract The mixture of normal distributions provides a useful extension of the normal distribution for modeling of daily changes in market variables with fatter-than-normal tails

  8. Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: IV The Controlling Parameters of the Starburst SED

    E-Print Network [OSTI]

    B. Groves; M. Dopita; R. Sutherland; L. Kewley; J. Fischera; C. Leitherer; B. Brandl; W. van Breugal

    2007-12-11T23:59:59.000Z

    We combine the the stellar spectral synthesis code Starburst99, the nebular modelling code MAPPINGSIII, and a 1-D dynamical evolution model of HII regions around massive clusters of young stars to generate improved models of the spectral energy distribution (SED) of starburst galaxies. We introduce a compactness parameter, C, which characterizes the specific intensity of the radiation field at ionization fronts in HII regions, and which controls the shape of the far-IR dust re-emission, often referred to loosely as the dust ``temperature''. We also investigate the effect of metallicity on the overall SED and in particular, on the strength of the PAH features. We provide templates for the mean emission produced by the young compact HII regions, the older (10 - 100 Myr) stars and for the wavelength-dependent attenuation produced by a foreground screen of the dust used in our model. We demonstrate that these components may be combined to produce a excellent fit to the observed SEDs of star formation dominated galaxies which are often used as templates (Arp 220 and NGC 6240). This fit extends from the Lyman Limit to wavelengths of about one mm. The methods presented in both this paper and in the previous papers of this series allow the extraction of the physical parameters of the starburst region (star formation rates, star formation rate history, mean cluster mass, metallicity, dust attenuation and pressure) from the analysis of the pan-spectral SED.

  9. 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, ...

  10. 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

  11. Modeling and responding to pandemic influenza : importance of population distributional attributes and non-pharmaceutical interventions

    E-Print Network [OSTI]

    Nigmatulina, Karima Robert

    2009-01-01T23:59:59.000Z

    After reviewing prevalent approaches to the modeling pandemic influenza transmission, we present a simple distributional model that captures the most significant population attributes that alter the dynamics of the outbreak. ...

  12. FUTURE POWER GRID INITIATIVE Modeling of Distributed Energy

    E-Print Network [OSTI]

    models by utility companies to support their demand response operations. APPROACH Development module) » modeling of the response scheme (control module) » modeling of the aggregated effects and detailed model and will be followed by a calibration procedure. Approaches to build aggregated models

  13. Distributed state estimation and model predictive control of linear interconnected system

    E-Print Network [OSTI]

    Boyer, Edmond

    requirements, modern control systems are becoming more and more complex. For these processes, different controlDistributed state estimation and model predictive control of linear interconnected system: In this paper, a distributed and networked control system architecture based on independent Model Predictive

  14. Spatial Distribution Of Cerium Valence In Model Planar Pd/Ce0...

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

    Distribution Of Cerium Valence In Model Planar PdCe0.7Zr0.3O2 Catalysts. Spatial Distribution Of Cerium Valence In Model Planar PdCe0.7Zr0.3O2 Catalysts. Abstract: The spatial...

  15. Modeling and Simulation of the EV Charging in a Residential Distribution Power Grid

    E-Print Network [OSTI]

    Al Faruque, Mohammad Abdullah

    in GridLAB-D (an open-source software tool used to model, simulate, and analyze power distribution systems Vehicle, Electric Vehicle Supply Equipment, GridLAB-D, Residential Distribution Power Grid I. INTRODUCTION with Electric Vehicle Supply Equipment (EVSE) and EVs. The scope of this paper is to model the EV

  16. Probabilistic Modelling of Plug-in Hybrid Electric Vehicle Impacts on Distribution Networks in

    E-Print Network [OSTI]

    Victoria, University of

    Probabilistic Modelling of Plug-in Hybrid Electric Vehicle Impacts on Distribution Networks Committee Probabilistic Modelling of Plug-in Hybrid Electric Vehicle Impacts on Distribution Networks) Departmental Member Plug-in hybrid electric vehicles (PHEVs) represent a promising future direction

  17. Exact Maximum Likelihood estimator for the BL-GARCH model under elliptical distributed

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Exact Maximum Likelihood estimator for the BL-GARCH model under elliptical distributed innovations, Brisbane QLD 4001, Australia Abstract We are interested in the parametric class of Bilinear GARCH (BL-GARCH examine, in this paper, the BL-GARCH model in a general setting under some non-normal distributions. We

  18. Double-pulse Brillouin distributed optical fiber sensors: analytical model and experimental validation

    E-Print Network [OSTI]

    Thévenaz, Jacques

    Double-pulse Brillouin distributed optical fiber sensors: analytical model and experimental-pulse Brillouin optical time-domain analysis (DP-BOTDA) sensors. The proposed model is a tool that provides a full. Keywords: Stimulated Brillouin scattering, distributed optical fiber sensor, temperature sensing, strain

  19. A Cartesian Robot for RFID Signal Distribution Model Verification Aliasgar Kutiyanawala and Vladimir Kulyukin

    E-Print Network [OSTI]

    Kulyukin, Vladimir

    the design and implementation of a Cartesian robot for verifying and constructing signal distribution models. In this paper, we present the design and implementation of a Cartesian robot for verifying and constructingA Cartesian Robot for RFID Signal Distribution Model Verification Aliasgar Kutiyanawala

  20. A forward microphysical model to predict the size-distribution parameters of laboratory generated (mimic)

    E-Print Network [OSTI]

    Oxford, University of

    A forward microphysical model to predict the size- distribution parameters of laboratory generated Interactions ­ Condensational Growth and Coagulation, Submitted for Indian Aerosol Science and Technology Microphysical Model for the UTLS (FAMMUS) is applied to predict the size-distribution parameters of laboratory

  1. Modeled climate change effects on distributions of Canadian butterfly species

    E-Print Network [OSTI]

    Peterson, A. Townsend; Martí nez-Meyer, Enrique; Gonzá lez-Salazar, Constantino; Hall, Peter W.

    2004-07-30T23:59:59.000Z

    Abstract: Climate change effects on biodiversity are being documented now frequently in the form of changes in phenology and distributional shifts. However, the form that these effects will take over a longer timespan is ...

  2. Conduction Models Of The Temperature Distribution In The East...

    Open Energy Info (EERE)

    Geothermal Project well HGP-A are simulated by model studies using a finite element code for conductive heat flow. Three models were generated: a constant temperature source...

  3. IMPROVED MODELING OF THE MASS DISTRIBUTION OF DISK GALAXIES BY THE EINASTO HALO MODEL

    SciTech Connect (OSTI)

    Chemin, Laurent [Universite de Bordeaux, Observatoire Aquitain des Sciences de l'Univers, BP 89, 33271 Floirac Cedex (France); De Blok, W. J. G. [ACGC, Department of Astronomy, University of Cape Town, Rondebosch 7700 (South Africa); Mamon, Gary A., E-mail: chemin@obs.u-bordeaux1.fr, E-mail: edeblok@ast.uct.ac.za, E-mail: gam@iap.fr [Institut d'Astrophysique de Paris (UMR 7095: CNRS and UPMC), 98 bis Bd. Arago, 75014 Paris (France)

    2011-10-15T23:59:59.000Z

    Analysis of the rotation curves (RCs) of spiral galaxies provides an efficient diagnostic for studying the properties of dark matter halos and their relations with baryonic material. Since the cored pseudo-isothermal (Iso) model usually provides a better description of observed RCs than does the cuspy Navarro-Frenk-White (NFW) model, there have been concerns that the {Lambda}CDM primordial density fluctuation spectrum may not be the correct one. We have modeled the RCs of galaxies from The H I Nearby Galaxy Survey (THINGS) with the Einasto halo model, which has emerged as the best-fitting model of the halos arising in dissipationless cosmological N-body simulations. We find that the RCs are significantly better fit with the Einasto halo than with either Iso or NFW halo models. In our best-fit Einasto models, the radius of density slope -2 and the density at this radius are highly correlated. The Einasto index, which controls the overall shape of the density profile, is near unity on average for intermediate and low mass halos. This is not in agreement with the predictions from {Lambda}CDM simulations. The indices of the most massive halos are in rough agreement with those cosmological simulations and appear correlated with the halo virial mass. We find that a typical Einasto density profile declines more strongly in its outermost parts than any of the Iso or NFW models whereas it is relatively shallow in its innermost regions. The core nature of those regions of halos thus extends the cusp-core controversy found for the NFW model with low surface density galaxies to the Einasto halo with more massive galaxies like those of THINGS. The Einasto concentrations decrease as a function of halo mass, in agreement with trends seen in numerical simulations. However, they are generally smaller than values expected for simulated Einasto halos. We thus find that, so far, the Einasto halo model provides the best match to the observed RCs and can therefore be considered as a new standard model for dark matter halos.

  4. 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.

  5. Les business models dans la distribution : reprer les chemins de la performance 1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Les business models dans la distribution : repérer les chemins de la performance 1 Pierre Volle peuvent être adressées à pierre.volle@dauphine.fr 2 Les business models dans la distribution : repérer les business model (BM) reste largement à préciser. L'objectif de cet article est donc de mettre en évidence

  6. Building Responsive and Reliable Distributed Services: Models and Design

    E-Print Network [OSTI]

    Newcastle upon Tyne, University of

    consequences of these failures. For example, in a reactor safety system, the primary functionality concerns and management of safety critical distributed systems. NATS monitors and decides the flight paths of civilian aircrafts in the British air space. Its operations are conducted centrally from West Drayton, and its

  7. Asymptotic Approximations to the Distributed Activation Energy Model

    E-Print Network [OSTI]

    McGuinness, Mark

    applicability in situations, such as computational fluid dynamics modelling of coal-fired boilers, where- plex chemical systems such as coal pyrolysis. MRM assumes that the process can be represented Energy Model (DAEM) or multiple reaction model (MRM) for coal pyrolysis [4] may be applied to either

  8. 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 ...

  9. 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

  10. 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

  11. 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

  12. 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

  13. Quantified regional and laminar distribution of the noradrenaline innervation in the anterior half of the adult rat cerebral cortex

    SciTech Connect (OSTI)

    Audet, M.A.; Doucet, G.; Oleskevich, S.; Descarries, L.

    1988-08-15T23:59:59.000Z

    The regional and laminar distribution of the noradrenaline (NA) innervation in the adult rat cerebral cortex was quantified in radioautographs of semithin sections from whole hemisphere slices incubated with tritiated catecholamines and a monoamine oxidase inhibitor. Uptake-labeled axonal varicosities (aggregates of silver grains) were counted with the help of a computerized image analyzer in seven cytoarchitectonic areas of the rostral half of the cortex: Cg3, rostral AID, Cg2, Fr1, Par1, caudal AID, and Pir (prepiriform) according to Zilles's nomenclature. Both dopamine (DA) and NA terminals were detected after incubation with (3H)DA and citalopram or with (3H)NA alone. In the presence of desipramine (DMI), DA terminals alone were demonstrated; the number of NA terminals was then obtained by subtraction from counts in adjacent slices incubated with or without DMI. These counts suggested that DA and NA varicosities were fully visualized only after labeling with their respective tritiated amine. Similar numbers of labeled NA varicosities as inferred after (3H)NA incubation with or without DMI were observed after (3H)NA incubation in the presence of benztropine (BZ). This indicated that NA terminals were then maximally detected to the exclusion of the DA ones, and the latter approach was adopted for the acquisition of normative data. Since the average diameter of the labeled NA varicosities was known from earlier measurements in electron microscope radioautographs, the initial counts of labeled sites/mm2 of histological section could be expressed as numbers of varicosities/mm3 of tissue following a double correction for incomplete detection at the chosen duration of radioautographic exposure and section thickness.

  14. 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

  15. Estimating sandstone permeability using network models with pore size distributions

    E-Print Network [OSTI]

    Mathews, Alan Ronald

    1991-01-01T23:59:59.000Z

    the effects of each parameter on the response of the network lattice. A FoR+RAv source code was written to generate and analyze the response of the network model (see Appendix G for source code description and flow chart). The controlling parameters used... in appearance to empirical data. A network model is developed to simulate the pore geometry of a clean, well-sorted sandstone. Pores were modeled as straight capillaries connected in various lattice configurations. Complex lattice configurations produce more...

  16. Modeling of Thermal Storage Systems in MILP Distributed Energy Resource Models

    E-Print Network [OSTI]

    Steen, David

    2014-01-01T23:59:59.000Z

    and a Ph.D. in Energy and Resources, all from the Universityof distributed energy resources," in Power and EnergyPouresmaeil, "Distributed energy resources and benefits to

  17. Modeling the reactive inorganic solute distributions in the groundwater flow systems of the Hanford Site using inverse analytical modeling techniques

    E-Print Network [OSTI]

    Adamski, Mark Robert

    1993-01-01T23:59:59.000Z

    Inverse analytical techniques were used to model solute distributions and determine transport parameters for two flow systems in the Yakima Basalt subgroup at the Hanford Site in Washington state. Previous studies of these flow systems used...

  18. Mining for Statistical Models of Availability in Large-Scale Distributed Systems

    E-Print Network [OSTI]

    Kondo, Derrick

    Mining for Statistical Models of Availability in Large-Scale Distributed Systems: An Empirical and Telecommunication Systems (MASCOTS 2009) B. Javadi (INRIA) Statistical Models of Availability MASCOTS 2009 1 / 34) Statistical Models of Availability MASCOTS 2009 2 / 34 #12;Introduction and Motivation P2P, Grid, Cloud

  19. Semi-distributed lumped model of a karst system under active1 management2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    system27 28 Keywords29 Impulse response30 Groundwater flow modeling31 Groundwater level fluctuations32 Pumping33 Introduction34 Numerical models for karst aquifers usually fall within two main categories1 Semi-distributed lumped model of a karst system under active1 management2 Bernard LADOUCHE1

  20. Distributed Versioning Model for MOF* Petr Hntynka1

    E-Print Network [OSTI]

    activities of OMG: It is addressed in the Model-Driven Architecture (MDA), namely in the Meta Object Facility (MOF), one of the tools MDA provides for developers. 1.1 MDA Model-Driven Architecture [16 of MDA is to separate the functional specification of a designed system and the implementation

  1. Dalton Lecture: How far can we go in distributed hydrological modelling?Hydrology and Earth System Sciences, 5(1), 1-12 (2001) EGS How far can we go in distributed hydrological modelling?

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Dalton Lecture: How far can we go in distributed hydrological modelling?Hydrology and Earth System Sciences, 5(1), 1-12 (2001) © EGS How far can we go in distributed hydrological modelling? Keith hydrological models in hydrology as an expression of a pragmatic realism. Some of the problems of distributed

  2. Application of the Gebhart-Block Model for Predicting Vertical Temperature Distribution in a Large Space Building with Natural Ventilation

    E-Print Network [OSTI]

    Huang, C.; Song, Y.; Luo, X.

    2006-01-01T23:59:59.000Z

    Based on the Block model for predicting vertical temperature distribution in a large space, this paper describes an improved Gebhart-Block model for predicting vertical temperature distribution of a large space with natural ventilation...

  3. Model-predicted distribution of wind-induced internal wave energy in the world's oceans

    E-Print Network [OSTI]

    Miami, University of

    Model-predicted distribution of wind-induced internal wave energy in the world's oceans Naoki 9 July 2008; published 30 September 2008. [1] The distribution of wind-induced internal wave energy-induced internal wave energy in the world's oceans, J. Geophys. Res., 113, C09034, doi:10.1029/2008JC004768. 1

  4. Metadata Modeling for Quality of Service Management in Distributed Multimedia Systems1

    E-Print Network [OSTI]

    von Bochmann, Gregor

    Metadata Modeling for Quality of Service Management in Distributed Multimedia Systems1 Brigitte.Anne}@uqam.ca E-mail:{bochmann, hafid}@iro.umontreal.ca Abstract In distributed multimedia systems, since multimedia objects are voluminous and unstructured, manipulation, transfer and visualization of such objects

  5. SUBGRID PARAMETERIZATION OF SNOW DISTRIBUTION FOR AN ENERGY AND MASS BALANCE SNOW COVER MODEL

    E-Print Network [OSTI]

    Tarboton, David

    SUBGRID PARAMETERIZATION OF SNOW DISTRIBUTION FOR AN ENERGY AND MASS BALANCE SNOW COVER MODEL & Sons, Ltd. #12;1 SUBGRID PARAMETERIZATION OF SNOW DISTRIBUTION FOR AN ENERGY AND MASS BALANCE SNOW of the lumped snowpack mass and energy balance applied to a 26-ha rangeland catchment with high spatial

  6. Modeling and evaluating the performance of Brillouin distributed optical fiber sensors

    E-Print Network [OSTI]

    Dalang, Robert C.

    Modeling and evaluating the performance of Brillouin distributed optical fiber sensors Marcelo A analysis of the key factors impacting on the performance of Brillouin distributed optical fiber sensors of America OCIS codes: (060.2310) Fiber optics; (060.2370) Fiber optics sensors; (290.5900) Scattering

  7. A model distribution function for relativistic bi-Maxwellian with drift

    SciTech Connect (OSTI)

    Naito, O. [Japan Atomic Energy Agency, 801-1 Mukouyama, Naka, Ibaraki 311-0193 (Japan)

    2013-04-15T23:59:59.000Z

    A model distribution function for relativistic bi-Maxwellian with drift is proposed, based on the maximum entropy principle and the relativistic canonical transformation. Since the obtained expression is compatible with the existing distribution functions and has a relatively simple form as well as smoothness, it might serve as a useful tool in the research fields of space or high temperature fusion plasmas.

  8. 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.

  9. A model for net-baryon rapidity distribution

    E-Print Network [OSTI]

    J. Alvarez-Muñiz; R. Conceição; J. Dias de Deus; M. C. Espírito Santo; J. G. Milhano; M. Pimenta

    2009-03-10T23:59:59.000Z

    In nuclear collisions, a sizable fraction of the available energy is carried away by baryons. As the baryon number is conserved, the net-baryon $B-\\bar{B}$ retains information on the energy-momentum carried by the incoming nuclei. A simple and consistent model for net-baryon production in high energy proton-proton and nucleus-nucleus collisions is presented. The basic ingredients of the model are valence string formation based on standard PDFs with QCD evolution and string fragmentation via the Schwinger mechanism. The results of the model are presented and compared with data at different centre-of-mass energies and centralities, as well as with existing models. These results show that a good description of the main features of net-baryon data is possible in the framework of a simplistic model, with the advantage of making the fundamental production mechanisms manifest.

  10. 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.

  11. 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.

  12. Resonance recombination model and quark distribution functions in the quark-gluon plasma 

    E-Print Network [OSTI]

    Ravagli, L.; van Hees, H.; Rapp, Ralf.

    2009-01-01T23:59:59.000Z

    observed constituent quark number scaling (CQNS) at the Relativistic Heavy Ion Collider (RHIC). To address this problem we combine our earlier developed quark recombination model with quark phase-space distributions computed from relativistic Langevin...

  13. Using Solar Business Models to Expand the Distributed Wind Market (Presentation)

    SciTech Connect (OSTI)

    Savage, S.

    2013-05-01T23:59:59.000Z

    This presentation to attendees at Wind Powering America's All-States Summit in Chicago describes business models that were responsible for rapid growth in the solar industry and that may be applicable to the distributed wind industry as well.

  14. CVSys: A Coordination Framework for Dynamic and Fully Distributed Cardiovascular Modeling and Simulation

    E-Print Network [OSTI]

    California at Irvine, University of

    CVSys: A Coordination Framework for Dynamic and Fully Distributed Cardiovascular Modeling and dynamic simulation control. This coordination framework uniquely incorporates attributes of open indigenous and a more integrated system representation. Dynamic simulation control serves to interject new

  15. MODELING THE GRB HOST GALAXY MASS DISTRIBUTION: ARE GRBs UNBIASED TRACERS OF STAR FORMATION?

    E-Print Network [OSTI]

    Kocevski, Daniel

    We model the mass distribution of long gamma-ray burst (GRB) host galaxies given recent results suggesting that GRBs occur in low-metallicity environments. By utilizing measurements of the redshift evolution of the ...

  16. 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 ...

  17. A theoretical temperature distribution model for asymmetric and isotropic hollow-fiber bioreactors

    E-Print Network [OSTI]

    Nam, Ki Yun

    1986-01-01T23:59:59.000Z

    A THEOhZTICAL TEMPERATURE DISTRIBUTION MODEL FOR ASYMMETRIC AND ISOTROPIC HOLLOW-FIBER BIOREACTORS A Thesis KI YUN NAM Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1986 Major Subject: Chemical Engineering A THEORETICAL TEMPERATURE DISTRIBUTION MODEL FOR ASYMMETRIC AND ISOTROPIC HOLLOW-FIBER BIOREACTORS A Thesis KI YUN NAM Approved as to style snd content by: D. T. Hanson (Chairman...

  18. A computer simulation model for the prediction of temperature distributions in radiofrequency hyperthermia treatment

    E-Print Network [OSTI]

    Rothe, Jeanne Marie

    1983-01-01T23:59:59.000Z

    A COMPUTER SIMULATION MODEL FOR THE PREDICTION OF . EMPERATURE DISTRIBUTIONS IN RADIOFREQUENCY HYPERTHERMIA TREATMENT A Thesis by JEANNE MARIE ROTHE Submitted to the Graduate College of Texas ASM University in Partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE DECEMBER 1983 Major Subject: Bioengineering A COMPUTER SIMULATION MODEL FOR THE PREDICTION OF TEMPERATURE DISTRIBUTIONS IN RADIOFREQUENCY HYPERTHERMIA TREATMENT A Thesis by JEANNE MARIE ROTHE Approved...

  19. Semi-empirical model for depth dose distributions of megavoltage x-ray beams

    SciTech Connect (OSTI)

    Ahuja, S.D.; Stroup, S.L.; Bolin, M.G.

    1980-09-01T23:59:59.000Z

    The dose distribution due to absorption of photon energy fluence in a homogeneous water phantom irradiated by megavoltage x-ray beams has been analyzed with a semiempirical model. The method generalizes an analytical formalism for the scattering component of dose within a water phantom which was developed recently for monoenergetic photon beams. Contributions to dose via Compton interaction and pair creation form the essential structure of the secondary component formula. Both the central-axis percent depth dose and off-central-axis ratios can be determined for beams of different sizes, used at any value of source to surface distance. The input data include the values of linear attenuation and energy-absorption coefficients in water at energies between 10 keV and the equivalent energy of the beam. Predicted values of the central-axis percent depth dose and the off-central-axis ratios are compared with the measured data for 2, 4, 6, 8, 10, 14, 20, 35, 45, and 70 MVp x-ray beams. For the central-axis percent depth dose, agreement is within 3% for fields of sizes between 5 x 5 and 20 x 20 cm/sup 2/, and 5% for larger fields, for beams of MVp up to 20. For higher energy beams, comparison was made only for the 10 x 10 cm/sup 2/ fields and the discrepancies were within 3%. For the off-central-axis ratios, agreement between the predicted and measured values is within 5% over the umbra region but worsens in the penumbra region and geometrical shadow. This formalism requires large computer storage for generating data for all realistic beams irradiating normal-size phantoms.

  20. Using species distribution models to inform IUCN Red List assessments

    E-Print Network [OSTI]

    Syfert, Mindy M.; Joppa, Lucas; Smith, Matthew J.; Coomes, David A.; Bachman, Steven P.; Brummitt, Neil A.

    2014-07-26T23:59:59.000Z

    .g. hurricanes) or anthropogenic effects (e.g. deforestation) not included in the model fitting process (Elith and Leathwick 2009). Additionally, the SDM approach we have taken here does not explicitly take into account non-equilibrium species dynamics. While...

  1. A Bose-Einstein Model of Particle Multiplicity Distributions

    E-Print Network [OSTI]

    A. Z. Mekjian; T. Csorgo; S. Hegyi

    2006-12-19T23:59:59.000Z

    A model of particle production is developed based on a parallel with a theory of Bose-Einstein condensation and similarities with other critical phenomena such as critical opalescence. The role of a power law critical exponent tau and Levy index alpha are studied. Various features of this model are developed and compared with other commonly used models of particle production which are shown to differ by having different values for tau, alpha. While void scaling is a feature of this model, hierarchical structure is not a general property of it. The value of the exponent tau=2 is a transition point associated with void and hierarchical scaling features. An exponent gamma is introduced to describe enhanced fluctuations near a critical point. Experimentally determined properties of the void scaling function can be used to determine tau.

  2. Distributed GIS for Monitoring and Modeling Urban Air Quality

    E-Print Network [OSTI]

    Yeang, Chen-Hsiang, 1969-

    The progress of technology has made the measurement of air quality and the simulation of complex air pollution models both feasible and cost-effective. However, there is a long way to go in terms of facilitating widespread ...

  3. A diameter distribution model for even-aged beech in Denmark Thomas Nord-Larsen a,*, Quang V. Cao b

    E-Print Network [OSTI]

    Cao, Quang V.

    A diameter distribution model for even-aged beech in Denmark Thomas Nord-Larsen a,*, Quang V. Cao b 2006 Abstract We developed a diameter distribution model for even-aged stands of European beech in Denmark using the Weibull distribution. The model parameters were estimated using a large dataset from

  4. 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.

  5. OXYGEN DEPLETION IN THE INTERSTELLAR MEDIUM: IMPLICATIONS FOR GRAIN MODELS AND THE DISTRIBUTION OF ELEMENTAL OXYGEN

    SciTech Connect (OSTI)

    Whittet, D. C. B. [New York Center for Astrobiology, and Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States)

    2010-02-20T23:59:59.000Z

    This paper assesses the implications of a recent discovery that atomic oxygen is being depleted from diffuse interstellar gas at a rate that cannot be accounted for by its presence in silicate and metallic oxide particles. To place this discovery in context, the uptake of elemental O into dust is considered over a wide range of environments, from the tenuous intercloud gas and diffuse clouds sampled by the depletion observations to dense clouds where ice mantles and gaseous CO become important reservoirs of O. The distribution of O in these contrasting regions is quantified in terms of a common parameter, the mean number density of hydrogen (n{sub H}). At the interface between diffuse and dense phases (just before the onset of ice-mantle growth) as much as {approx}160 ppm of the O abundance is unaccounted for. If this reservoir of depleted oxygen persists to higher densities it has implications for the oxygen budget in molecular clouds, where a shortfall of the same order is observed. Of various potential carriers, the most plausible appears to be a form of O-bearing carbonaceous matter similar to the organics found in cometary particles returned by the Stardust mission. The 'organic refractory' model for interstellar dust is re-examined in the light of these findings, and it is concluded that further observations and laboratory work are needed to determine whether this class of material is present in quantities sufficient to account for a significant fraction of the unidentified depleted oxygen.

  6. 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

  7. Husimi distribution and phase space analysis of Dicke model quantum phase transition

    E-Print Network [OSTI]

    E. Romera; R. del Real; M. Calixto

    2014-09-19T23:59:59.000Z

    The Husimi distribution is proposed for a phase space analysis of quantum phase transitions in the Dicke model of spin-boson interactions. We show that the inverse participation ratio and Wehrl entropy of the Husimi distribution give sharp signatures of the quantum phase transition. The analysis has been done using two frameworks: a numerical treatment and an analytical variational approximation. Additionally we have proposed a new characterization of the Dicke model quantum phase transition by means of the zeros of the Husimi distribution in the variational approach.

  8. Regional Analysis of Building Distributed Energy Costs and CO2 Abatement: A U.S. - China Comparison

    E-Print Network [OSTI]

    Mendes, Goncalo

    2014-01-01T23:59:59.000Z

    cold climate zone) buildings use least energy compared to other cold regions, mainly because of its high altitude and ample solar

  9. Building Distributed Energy Performance Optimization for China a Regional Analysis of Building Energy Costs and CO2 Emissions

    E-Print Network [OSTI]

    Feng, Wei

    2013-01-01T23:59:59.000Z

    DER Technologies Cost Data in China (USD) Technologies Fixedin Northern China make the CHP system not cost-effective.for China -- a Regional Analysis of Building Energy Costs

  10. Translation techniques for distributed-shared memory programming models

    SciTech Connect (OSTI)

    Fuller, Douglas James

    2005-08-01T23:59:59.000Z

    The high performance computing community has experienced an explosive improvement in distributed-shared memory hardware. Driven by increasing real-world problem complexity, this explosion has ushered in vast numbers of new systems. Each new system presents new challenges to programmers and application developers. Part of the challenge is adapting to new architectures with new performance characteristics. Different vendors release systems with widely varying architectures that perform differently in different situations. Furthermore, since vendors need only provide a single performance number (total MFLOPS, typically for a single benchmark), they only have strong incentive initially to optimize the API of their choice. Consequently, only a fraction of the available APIs are well optimized on most systems. This causes issues porting and writing maintainable software, let alone issues for programmers burdened with mastering each new API as it is released. Also, programmers wishing to use a certain machine must choose their API based on the underlying hardware instead of the application. This thesis argues that a flexible, extensible translator for distributed-shared memory APIs can help address some of these issues. For example, a translator might take as input code in one API and output an equivalent program in another. Such a translator could provide instant porting for applications to new systems that do not support the application's library or language natively. While open-source APIs are abundant, they do not perform optimally everywhere. A translator would also allow performance testing using a single base code translated to a number of different APIs. Most significantly, this type of translator frees programmers to select the most appropriate API for a given application based on the application (and developer) itself instead of the underlying hardware.

  11. The determination of the Reynolds shear stress distribution in the transition region resulting from a sudden increase in wall roughness in a two-dimensional channel

    E-Print Network [OSTI]

    Heilhecker, Joe Keith

    1962-01-01T23:59:59.000Z

    THE DETERMINATION OF THE REYNOLDS SHEAR STRESS DISTRIBUTION IN THE TRANSITION REGION RESULTING FROM A SUDDEN INCREASE IN WALL ROUGHNESS IN A TWO-DIMENSIONAL CHANNEL A Thesis By JOE K. HEI LHE CKER Submitted to the Graduate School... REGION RESULTING FROM A SUDDEN INCREASE IN WALL ROUGHNESS IN A TWO-DIMEN4$ONAL CHANNEL A Thesis By JOE K. HEI LHE CKER Approved as to style and content by: (Chairm o C mittee) (Head of Department) May 1962 TAB LE OF CONTE NT S Page List...

  12. 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.

  13. 2-level environmental-stress-screening (ESS) model: A mixed-distribution approach

    SciTech Connect (OSTI)

    Reddy, R.K.; Dietrich, D.L.

    1994-03-01T23:59:59.000Z

    Environmental stress screening (ESS) is used to reduce, if not eliminate, the occurrence of some types of failures from the field by fixing them before the product is deployed. This paper models a 2-level ESS program where screening is performed at the part & unit levels. The parts are screened for a specified duration before being assembled into a unit. Defects induced during the assembly process are screened at the unit level. These parts & connections are assumed to come from either a good or a substandard population, and their times-to-failure distributions are modeled by mixed distributions. The optimal screening durations are obtained by minimizing the life-cycle cost. The model is simple to use and its viability is illustrated using mixed exponential distributions. The implementation of screens at various levels depends on costs and failure distribution characteristics. 13 refs.

  14. 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.

  15. 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.

  16. 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.

  17. 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)

  18. 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 15 June 2007 #12;with updated simulation results-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

  19. Model for energy efficiency in radio over fiber distributed indoor antenna Wi-Fi network

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Model for energy efficiency in radio over fiber distributed indoor antenna Wi-Fi network Yves Josse communications in indoor environments. In this paper, the power consumption and energy efficiency of a DAS using for different transmission configurations, yielding a distance- dependent energy efficiency model. In a second

  20. Current Distribution Models for the Earth's Main Magnetic Field: A Discrete Inverse Theory Approach

    E-Print Network [OSTI]

    Sewards, Terence V

    2008-01-01T23:59:59.000Z

    Current source models for the Earth's main geomagnetic field are calculated employing conventional discrete inverse theory methods. Source structures are spherical surfaces placed at the surface of the Earth's core, and at the surface of the Earth. The data set consists of measurements taken by the MAGSAT satellite in 1979. The resulting current distributions are discussed in relation to dipole and current loop models.

  1. A differentiable dynamic network loading model that yields queue length distributions and accounts for spillback

    E-Print Network [OSTI]

    Bierlaire, Michel

    A differentiable dynamic network loading model that yields queue length distributions and accounts, this is so because the kinematic wave model (KWM), the mainstay of traffic flow theory, only applies for spillback Carolina Osorio Gunnar Fl¨otter¨od Michel Bierlaire Abstract We derive a dynamic network

  2. Sub-grid parameterization of snow distribution for an energy and mass balance snow cover model

    E-Print Network [OSTI]

    Sub-grid parameterization of snow distribution for an energy and mass balance snow cover model model of the lumped snowpack mass and energy balance applied to a 26-ha rangeland catchment with high (Af). The energy state variable is evolved through an energy balance. The snow water equivalence state

  3. ASYMPTOTIC DISTRIBUTION OF ESTIMATES FOR A TIME-VARYING PARAMETER IN A HARMONIC MODEL

    E-Print Network [OSTI]

    Irizarry, Rafael A.

    ASYMPTOTIC DISTRIBUTION OF ESTIMATES FOR A TIME-VARYING PARAMETER IN A HARMONIC MODEL WITH MULTIPLE harmonic regression models are useful for cases where harmonic parameters appear to be time-varying. Least, harmonic regression, signal processing, sound analysis, time-varying parameters, weighted least squares

  4. Parameter Estimation in Groundwater Flow Models with Distributed and Pointwise Observations*

    E-Print Network [OSTI]

    Parameter Estimation in Groundwater Flow Models with Distributed and Pointwise Observations* Ben G concerning the least sqaures estimation of parameters in a groundwater flow model. As is typically the case­93­1­0153. #12; 1 Introduction Understanding the flow of groundwater is an important scientific and engineering

  5. Modeling Distribution Connected PV and Interconnection Study Analysis

    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. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. William Hirst HirstModeling &

  6. Model for Sustainable Urban Design With Expanded Sections on Distributed

    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 DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment3311,OfficialProducts | Department of| DepartmentModelEnergy

  7. Spatial distributions in static heavy-light mesons: a comparison of quark models with lattice QCD

    E-Print Network [OSTI]

    Damir Becirevic; Emmanuel Chang; Alain Le Yaouanc Luis Oliver; Jean-Claude Raynal

    2011-09-19T23:59:59.000Z

    Lattice measurements of spatial distributions of the light quark bilinear densities in static mesons allow to test directly and in detail the wave functions of quark models. These distributions are gauge invariant quantities directly related to the spatial distribution of wave functions. We make a detailed comparison of the recent lattice QCD results with our own quark models, formulated previously for quite different purposes. We find a striking agreement not only between our two quark models, but also with the lattice QCD data for the ground state in an important range of distances up to about 4/GeV. Moreover the agreement extends to the L=1 states [j^P=(1/2)^+]. An explanation of several particular features completely at odds with the non-relativistic approximation is provided. A rather direct, somewhat unexpected and of course approximate relation between wave functions of certain quark models and QCD has been established.

  8. Ripe for investment : refocusing the food desert debate on smaller stores, wholesale markets and regional distribution systems

    E-Print Network [OSTI]

    Tamis, Laurie P

    2009-01-01T23:59:59.000Z

    This thesis argues that food distribution systems must be strengthened in order to address the challenge of urban food access. The argument rests on a historical analysis of the supermarket industry and a comparative study ...

  9. Application of the CALIOP Layer Product to Evaluate the Vertical Distribution of Aerosols Estimated by Global Models: AeroCom Phase I Results

    SciTech Connect (OSTI)

    Koffi, Brigitte; Schultz, Michael; Breon, Francois-Marie; Griesfeller, Jan; Winker, D.; Balkanski, Y.; Bauer, Susanne E.; Berntsen, T.; Chin, Mian; Collins, William D.; Dentener, Frank; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Ginoux, P.; Gong, S.; Horowitz, L.; Iversen, T.; Kirkevag, A.; Koch, Dorothy; Krol, Maarten; Myhre, G.; Stier, P.; Takemura, T.

    2012-05-19T23:59:59.000Z

    The CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution of aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub-continental regions representative of industrial, dust, and biomass burning pollution, from CALIOP 2007-2009 observations and from AeroCom (Aerosol Comparisons between Observations and Models) 2000 simulations. An extinction mean height diagnostic (Z{sub a}) is defined to quantitatively assess the models performance. It is calculated over the 0-6 km and 0-10 km altitude ranges by weighting the altitude of each 100 m altitude layer by its aerosol extinction coefficient. The mean extinction profiles derived from CALIOP layer products provide consistent regional and seasonal specificities and a low inter-annual variability. While the outputs from most models are significantly correlated with the observed Z{sub a} climatologies, some do better than others, and 2 of the 12 models perform particularly well in all seasons. Over industrial and maritime regions, most models show higher Z{sub a} than observed by CALIOP, whereas over the African and Chinese dust source regions, Z{sub a} is underestimated during Northern Hemisphere Spring and Summer. The positive model bias in Z{sub a} is mainly due to an overestimate of the extinction above 6 km. Potential CALIOP and model limitations, and methodological factors that might contribute to the differences are discussed.

  10. 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.

  11. Regional Analysis of Building Distributed Energy Costs and CO2 Abatement: A U.S. - China Comparison

    E-Print Network [OSTI]

    Mendes, Goncalo

    2014-01-01T23:59:59.000Z

    performance and cost parameters in China are similar tofor China - a Regional Analysis of Building Energy Costs andNorthern China uses district heating systems, as the cost of

  12. 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.

  13. Event simulations in a transport model for intermediate energy heavy ion collisions: Applications to multiplicity distributions

    E-Print Network [OSTI]

    Mallik, S; Chaudhuri, G

    2015-01-01T23:59:59.000Z

    We perform transport model calculations for central collisions of mass 120 on mass 120 at laboratory beam energy in the range 20 MeV/nucleon to 200 MeV/nucleon. A simplified yet accurate method allows calculation of fluctuations in systems much larger than what was considered feasible in a well-known and already existing model. The calculations produce clusters. The distribution of clusters is remarkably similar to that obtained in equilibrium statistical model.

  14. Event simulations in a transport model for intermediate energy heavy ion collisions: Applications to multiplicity distributions

    E-Print Network [OSTI]

    S. Mallik; S. Das Gupta; G. Chaudhuri

    2015-03-19T23:59:59.000Z

    We perform transport model calculations for central collisions of mass 120 on mass 120 at laboratory beam energy in the range 20 MeV/nucleon to 200 MeV/nucleon. A simplified yet accurate method allows calculation of fluctuations in systems much larger than what was considered feasible in a well-known and already existing model. The calculations produce clusters. The distribution of clusters is remarkably similar to that obtained in equilibrium statistical model.

  15. Evolution of soot size distribution in premixed ethylene/air and ethylene/benzene/air flames: Experimental and modeling study

    SciTech Connect (OSTI)

    Echavarria, Carlos A.; Sarofim, Adel F.; Lighty, JoAnn S. [Department of Chemical Engineering, University of Utah, Salt Lake City, UT (United States); D'Anna, Andrea [Dipartimento di Ingegneria Chimica, Universita ''Federico II'' di Napoli, Naples (Italy)

    2011-01-15T23:59:59.000Z

    The effect of benzene concentration in the initial fuel on the evolution of soot size distribution in ethylene/air and ethylene/benzene/air flat flames was characterized by experimental measurements and model predictions of size and number concentration within the flames. Experimentally, a scanning mobility particle sizer was used to allow spatially resolved and online measurements of particle concentration and sizes in the nanometer-size range. The model couples a detailed kinetic scheme with a discrete-sectional approach to follow the transition from gas-phase to nascent particles and their coagulation to larger soot particles. The evolution of soot size distribution (experimental and modeled) in pure ethylene and ethylene flames doped with benzene showed a typical nucleation-sized (since particles do not actually nucleate in the classical sense particle inception is often used in place of nucleation) mode close to the burner surface, and a bimodal behavior at greater height above burner (HAB). However, major features were distinguished between the data sets. The growth of nucleation and agglomeration-sized particles was faster for ethylene/benzene/air flames, evidenced by the earlier presence of bimodality in these flames. The most significant changes in size distribution were attributed to an increase in benzene concentration in the initial fuel. However, these changes were more evident for high temperature flames. In agreement with the experimental data, the model also predicted the decrease of nucleation-sized particles in the postflame region for ethylene flames doped with benzene. This behavior was associated with the decrease of soot precursors after the main oxidation zone of the flames. (author)

  16. 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.

  17. Maximum Entropy Models of Shortest Path and Outbreak Distributions in Networks

    E-Print Network [OSTI]

    Bauckhage, Christian; Hadiji, Fabian

    2015-01-01T23:59:59.000Z

    Properties of networks are often characterized in terms of features such as node degree distributions, average path lengths, diameters, or clustering coefficients. Here, we study shortest path length distributions. On the one hand, average as well as maximum distances can be determined therefrom; on the other hand, they are closely related to the dynamics of network spreading processes. Because of the combinatorial nature of networks, we apply maximum entropy arguments to derive a general, physically plausible model. In particular, we establish the generalized Gamma distribution as a continuous characterization of shortest path length histograms of networks or arbitrary topology. Experimental evaluations corroborate our theoretical results.

  18. Modeling of stress distributions on the microstructural level in Alloy 600

    SciTech Connect (OSTI)

    Kozaczek, K.J. [Oak Ridge National Lab., TN (United States); Petrovic, B.G.; Ruud, C.O. [Pennsylvania State Univ., University Park, PA (United States); Mcllree, A.R. [Electric Power Research Inst., Palo Alto, CA (United States)

    1995-04-01T23:59:59.000Z

    Stress distribution in a random polycrystalline material (Alloy 600) was studied using a topologically correct microstructural model. Distributions of von Mises and hydrostatic stresses at the grain vertices, which could be important in intergranular stress corrosion cracking, were analyzed as functions of microstructure, grain orientations and loading conditions. Grain size, shape, and orientation had a more pronounced effect on stress distribution than loading conditions. At grain vertices the stress concentration factor was higher for hydrostatic stress (1.7) than for von Mises stress (1.5). The stress/strain distribution in the volume (grain interiors) is a normal distribution and does not depend on the location of the studied material volume i.e., surface vs/bulk. The analysis of stress distribution in the volume showed the von Mises stress concentration of 1.75 and stress concentration of 2.2 for the hydrostatic pressure. The observed stress concentration is high enough to cause localized plastic microdeformation, even when the polycrystalline aggregate is in the macroscopic elastic regime. Modeling of stresses and strains in polycrystalline materials can identify the microstructures (grain size distributions, texture) intrinsically susceptible to stress/strain concentrations and justify the correctness of applied stress state during the stress corrosion cracking tests. Also, it supplies the information necessary to formulate the local failure criteria and interpret of nondestructive stress measurements.

  19. Evaluating Domestic Hot Water Distribution System Options With Validated Analysis Models

    SciTech Connect (OSTI)

    Weitzel, E.; Hoeschele, M.

    2014-09-01T23:59:59.000Z

    A developing body of work is forming that collects data on domestic hot water consumption, water use behaviors, and energy efficiency of various distribution systems. A full distribution system developed in TRNSYS has been validated using field monitoring data and then exercised in a number of climates to understand climate impact on performance. This study builds upon previous analysis modelling work to evaluate differing distribution systems and the sensitivities of water heating energy and water use efficiency to variations of climate, load, distribution type, insulation and compact plumbing practices. Overall 124 different TRNSYS models were simulated. Of the configurations evaluated, distribution losses account for 13-29% of the total water heating energy use and water use efficiency ranges from 11-22%. The base case, an uninsulated trunk and branch system sees the most improvement in energy consumption by insulating and locating the water heater central to all fixtures. Demand recirculation systems are not projected to provide significant energy savings and in some cases increase energy consumption. Water use is most efficient with demand recirculation systems, followed by the insulated trunk and branch system with a central water heater. Compact plumbing practices and insulation have the most impact on energy consumption (2-6% for insulation and 3-4% per 10 gallons of enclosed volume reduced). The results of this work are useful in informing future development of water heating best practices guides as well as more accurate (and simulation time efficient) distribution models for annual whole house simulation programs.

  20. 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.

  1. 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.

  2. Multiple-distribution-function lattice Boltzmann kinetic model for combustion phenomena

    E-Print Network [OSTI]

    Chuandong Lin; Aiguo Xu; Guangcai Zhang; Yingjun Li

    2014-05-21T23:59:59.000Z

    A hybrid kinetic model for combustion phenomena is proposed. The chemical reaction process is described by a phenomenological rate function. The flow behavior is described by a Lattice Boltzmann Kinetic Model (LBKM) with any number of distribution functions. As an example, we illustrate the case with only two distribution functions. One distribution function is used to describe the reactant, and the other one is used to describe the reaction product. Compared with the traditional fluid model for combustion, the new model can be used to study simultaneously both the hydrodynamic and the thermodynamic nonequilibrium behaviors. Compared with the previous LBKM-hybrid models with single distribution function, the new model can be used to study more carefully the combustion process, for example, the variations of the particle number densities, particle mass densities, flow velocities, internal energies per unit volume, internal energies per unit mass, temperatures, and pressures of each species and the whole of the system. It is found that both of chemical reactant and reaction product have different levels of deviation from their equilibrium state in different degrees of freedom. For a special degree of freedom, the deviation of chemical reactant from its equilibrium state is different from that of reaction product from its equilibrium state.

  3. Hardware model of a shipboard zonal electrical distribution system (ZEDS) : alternating current/direct current (AC/DC)

    E-Print Network [OSTI]

    Tidd, Chad N. (Chad Norman)

    2010-01-01T23:59:59.000Z

    A hardware model of a shipboard electrical distribution system based on aspects of the DDG 51 Flight IIA, Arleigh Burke class, 60Hz Alternating Current (AC) and the future direct current (DC), zonal electrical distribution ...

  4. DTE Energy Technologies With Detroit Edison Co. and Kinectrics Inc.: Distributed Resources Aggregation Modeling and Field Configuration Testing

    SciTech Connect (OSTI)

    Not Available

    2003-10-01T23:59:59.000Z

    Summarizes the work of DTE Energy Technologies, Detroit Edison, and Kinectrics, under contract to DOE's Distribution and Interconnection R&D, to develop distributed resources aggregation modeling and field configuration testing.

  5. 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.

  6. 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

  7. 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.

  8. 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...

  9. Improvement of capabilities of the Distributed Electrochemistry Modeling Tool for investigating SOFC long term performance

    SciTech Connect (OSTI)

    Gonzalez Galdamez, Rinaldo A.; Recknagle, Kurtis P.

    2012-04-30T23:59:59.000Z

    This report provides an overview of the work performed for Solid Oxide Fuel Cell (SOFC) modeling during the 2012 Winter/Spring Science Undergraduate Laboratory Internship at Pacific Northwest National Laboratory (PNNL). A brief introduction on the concept, operation basics and applications of fuel cells is given for the general audience. Further details are given regarding the modifications and improvements of the Distributed Electrochemistry (DEC) Modeling tool developed by PNNL engineers to model SOFC long term performance. Within this analysis, a literature review on anode degradation mechanisms is explained and future plans of implementing these into the DEC modeling tool are also proposed.

  10. 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.

  11. 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.

  12. Temperature distributions in the laser-heated diamond anvil cell from 3-D numerical modeling

    SciTech Connect (OSTI)

    Rainey, E. S. G.; Kavner, A. [Department of Earth and Space Sciences, University of California, Los Angeles, California 90095 (United States); Hernlund, J. W. [Department of Earth and Planetary Science, University of California, Berkeley, California 94720 (United States); Earth-Life Science Institute, Megoro, Tokyo 152-8551 (Japan)

    2013-11-28T23:59:59.000Z

    We present TempDAC, a 3-D numerical model for calculating the steady-state temperature distribution for continuous wave laser-heated experiments in the diamond anvil cell. TempDAC solves the steady heat conduction equation in three dimensions over the sample chamber, gasket, and diamond anvils and includes material-, temperature-, and direction-dependent thermal conductivity, while allowing for flexible sample geometries, laser beam intensity profile, and laser absorption properties. The model has been validated against an axisymmetric analytic solution for the temperature distribution within a laser-heated sample. Example calculations illustrate the importance of considering heat flow in three dimensions for the laser-heated diamond anvil cell. In particular, we show that a “flat top” input laser beam profile does not lead to a more uniform temperature distribution or flatter temperature gradients than a wide Gaussian laser beam.

  13. Building Distributed Energy Performance Optimization for China a Regional Analysis of Building Energy Costs and CO2 Emissions

    E-Print Network [OSTI]

    Feng, Wei

    2013-01-01T23:59:59.000Z

    Department of Energy Commercial Reference Building Models ofthe National Building Stock. Golden, Colorado: Nationaland Renewable Energy, Building Technologies Program, of the

  14. Blueshift Without Blueshift: Red Hole Gamma-Ray Burst Models Explain the Peak energy Distribution

    E-Print Network [OSTI]

    James S. Graber

    1999-12-15T23:59:59.000Z

    Gamma-ray bursts are still a puzzle. In particular, the central engine, the total energy and the very narrow distribution of peak energies challenge model builders. We consider here an extreme model of gamma-ray bursts based on highly red- and blue-shifted positron annihilation radiation. The burst emerges from inside the red hole created by the complete gravitational collapse of the GRB progenitor.

  15. 1 | P a g e Implementing an Integrated Distributed Model in Finance

    E-Print Network [OSTI]

    Ollivier-Gooch, Carl

    1 | P a g e Implementing an Integrated Distributed Model in Finance There are significant changes taking place, effective today, across the University's Finance function. These changes reflect some key opportunities for our finance professionals through mentoring, talent development, career laddering, mobility

  16. Calibration of a distributed flood forecasting model with input uncertainty using a Bayesian framework

    E-Print Network [OSTI]

    Hubbard, Susan

    Calibration of a distributed flood forecasting model with input uncertainty using a Bayesian; revised 20 June 2012; accepted 28 June 2012; published 15 August 2012. [1] In the process of calibrating that the developed method generally is effective in calibrating GBHM parameters and in estimating their associated

  17. Mathematical Model of Charge and Density Distributions in Interfacial Polymerization of Thin Films

    E-Print Network [OSTI]

    Freger, Viatcheslav "Slava"

    Mathematical Model of Charge and Density Distributions in Interfacial Polymerization of Thin Films INTRODUCTION Interfacial polymerization (IP) as a method of prepa- ration of thin film composite (TFC- tion. It has been shown that the formation of a thin film occurs very quickly and often results

  18. An Electricity Trade Model for Multiple Power Distribution Networks in Smart Energy Systems

    E-Print Network [OSTI]

    Pedram, Massoud

    . A microgrid is a small scale power network, which contains one or multiple types of renewable power generators complicated with the adoption of energy storage [5]. For a power network, the amount of energy generationAn Electricity Trade Model for Multiple Power Distribution Networks in Smart Energy Systems

  19. Fully Distributed Trust Model based on Trust Graph for Mobile Ad hoc Networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    University of Technology, France. bouabdal@hds.utc.fr Abstract A mobile ad hoc network (MANET) is a wireless pre-existing in- frastructure; all networking operations (routing, mobility management, and so onFully Distributed Trust Model based on Trust Graph for Mobile Ad hoc Networks Mawloud Omar, Yacine

  20. A Cartesian Robot for RFID Signal Distribution Model Verification Aliasgar Kutiyanawala Vladimir Kulyukin

    E-Print Network [OSTI]

    Kulyukin, Vladimir

    the design of a Cartesian robot for verifying the localization probability of a given PRF surface describe the design of a Cartesian robot for verifying the localization probability of a given PRF surfaceA Cartesian Robot for RFID Signal Distribution Model Verification Aliasgar Kutiyanawala Vladimir

  1. Modeling NoC Traffic Locality and Energy Consumption with Rent's Communication Probability Distribution

    E-Print Network [OSTI]

    Forrest, Stephanie

    Circuits]: Design aids--simulation; C.4 [Performance of Systems]: Modeling techiniques General Terms Design Distribution George B. P. Bezerra Dept. of Computer Science University of New Mexico Albuquerque, NM 87131 gbezerra@cs.unm.edu Stephanie Forrest Dept. of Computer Science University of New Mexico Albuquerque, NM

  2. Evaluation of distributed hydrologic impacts of temperature-index and energy-based snow models

    E-Print Network [OSTI]

    Dozier, Jeff

    Accepted 13 March 2013 Available online 26 March 2013 Keywords: Snow Energy-balance Temperature intercepts snow- fall, alters the snow/atmosphere energy exchange and reduces wind speed. Dense canopies tendEvaluation of distributed hydrologic impacts of temperature-index and energy-based snow models

  3. Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica

    E-Print Network [OSTI]

    Shapiro, Nikolai

    -flow measurements are rare or entirely absent. This will result in a smooth global heat-flow map that may proveInferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica Nikolai M. Shapiro*, Michael H. Ritzwoller Department of Physics, Center for Imaging the Earth

  4. Distributed Worm Simulation with a Realistic Internet Model Songjie Wei, Jelena Mirkovic, Martin Swany

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Distributed Worm Simulation with a Realistic Internet Model Songjie Wei, Jelena Mirkovic, Martin at work in its network. Aggressive worms further interact with the underlying Internet topology - the dynamics of the spread is constrained by the limited bandwidth of network links, and high-volume scan

  5. 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.

  6. Effective and Efficient Distributed Model-based Clustering Hans-Peter Kriegel, Peer Kroger, Alexey Pryakhin, Matthias Schubert

    E-Print Network [OSTI]

    Kriegel, Hans-Peter

    Effective and Efficient Distributed Model-based Clustering Hans-Peter Kriegel, Peer Kr¨oger, Alexey,kroegerp,pryakhin,schubert}@dbs.ifi.lmu.de Abstract In many companies data is distributed among several sites, i.e. each site generates its own data and manages its own data repository. Analyzing and mining these dis- tributed sources requires distributed

  7. 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

  8. Validation of a Hot Water Distribution Model Using Laboratory and Field Data

    SciTech Connect (OSTI)

    Backman, C.; Hoeschele, M.

    2013-07-01T23:59:59.000Z

    Characterizing the performance of hot water distribution systems is a critical step in developing best practice guidelines for the design and installation of high performance hot water systems. Developing and validating simulation models is critical to this effort, as well as collecting accurate input data to drive the models. In this project, the ARBI team validated the newly developed TRNSYS Type 604 pipe model against both detailed laboratory and field distribution system performance data. Validation efforts indicate that the model performs very well in handling different pipe materials, insulation cases, and varying hot water load conditions. Limitations of the model include the complexity of setting up the input file and long simulation run times. In addition to completing validation activities, this project looked at recent field hot water studies to better understand use patterns and potential behavioral changes as homeowners convert from conventional storage water heaters to gas tankless units. Based on these datasets, we conclude that the current Energy Factor test procedure overestimates typical use and underestimates the number of hot water draws. This has implications for both equipment and distribution system performance. Gas tankless water heaters were found to impact how people use hot water, but the data does not necessarily suggest an increase in usage. Further study in hot water usage and patterns is needed to better define these characteristics in different climates and home vintages.

  9. A Distributed Electrochemistry Modeling Tool for Simulating SOFC Performance and Degradation

    SciTech Connect (OSTI)

    Recknagle, Kurtis P.; Ryan, Emily M.; Khaleel, Mohammad A.

    2011-10-13T23:59:59.000Z

    This report presents a distributed electrochemistry (DEC) model capable of investigating the electrochemistry and local conditions with the SOFC MEA based on the local microstructure and multi-physics. The DEC model can calculate the global current-voltage (I-V) performance of the cell as determined by the spatially varying local conditions through the thickness of the electrodes and electrolyte. The simulation tool is able to investigate the electrochemical performance based on characteristics of the electrode microstructure, such as particle size, pore size, electrolyte and electrode phase volume fractions, and triple-phase-boundary length. It can also investigate performance as affected by fuel and oxidant gas flow distributions and other environmental/experimental conditions such as temperature and fuel gas composition. The long-term objective for the DEC modeling tool is to investigate factors that cause electrode degradation and the decay of SOFC performance which decrease longevity.

  10. The Distribution of Loop Lengths in Graphical Models for Turbo Decoding

    E-Print Network [OSTI]

    Smyth, Padhraic

    1 The Distribution of Loop Lengths in Graphical Models for Turbo Decoding Xianping Ge, David ¢¡£ ¢¡ ¡ ¤¡¥ ¢¡¦ ¢¡§ ¤¡¨ © £ © ¡ © ¥ © ¦ © § © ¨ £ £ £ ¡ £ ¥ £ ¦ £ § £ ¨ ¦ £ ¡ ¦ £ ¡ £ ¡ ¥ § ¨ £ ££ £ ¡ ¥ § ¨ £ ££ Fig. 1 The ADG model for a K = 6, N = 12, rate 1/2 turbo code. Abstract-- This paper analyzes the distribution of loop lengths in graphical models for turbo decoding. The prop- erties of such loops

  11. DISTRIBUTION AND RANGE OF RADIONUCLIDE SORPTION COEFFICIENTS IN A SAVANNAH RIVER SITE SUBSURFACE: STOCHASTIC MODELING CONSIDERATIONS

    SciTech Connect (OSTI)

    Kaplan, D.; et. al

    2010-01-11T23:59:59.000Z

    The uncertainty associated with the sorption coefficient, or K{sub d} value, is one of the key uncertainties in estimating risk associated with burying low-level nuclear waste in the subsurface. The objective of this study was to measure >648 K{sub d} values and provide a measure of the range and distribution (normal or log-normal) of radionuclide K{sub d} values appropriate for the E-Area disposal site, within the Savannah River Site, near Aiken South Carolina. The 95% confidence level for the mean K{sub d} was twice the mean in the Aquifer Zone (18-30.5 m depth), equal to the mean for the Upper Vadose Zone (3.3-10 m depth), and half the mean for the Lower Vadose Zone (3.10-18 m depth). The distribution of K{sub d} values was log normal in the Upper Vadose Zone and Aquifer Zone, and normal in the Lower Vadose Zone. To our knowledge, this is the first report of natural radionuclide Kd variability in the literature. Using ranges and distribution coefficients that are specific to the hydrostratigraphic unit improved model accuracy and reduced model uncertainty. Unfortunately, extension of these conclusions to other sites is likely not appropriate given that each site has its own sources of hydrogeological variability. However, this study provides one of the first examples of the development stochastic ranges and distributions of K{sub d} values for a hydrological unit for stochastic modeling.

  12. Model Based Commissioning Tool for Air-Conditioning Distribution Systems-APCBC

    E-Print Network [OSTI]

    Yoshida, H.; Noda, T.

    2014-01-01T23:59:59.000Z

    on Building Commissioning) Sept. 2014, Beijing, China ESL-IC-14-09-06 Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 1. Issues 2. Simulation Model of Distribution System 3. Example... of VWV System 4. Example of VAV System 5. Conclusions 2 ESL-IC-14-09-06 Proceedings of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 ? Energy consumption of air and water distribution in air...

  13. 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.

  14. Evaluation of a spatially-distributed Thornthwaite water-balance model

    SciTech Connect (OSTI)

    Lough, J.A. (Univ. of New Hampshire, Durham, NH (United States). Complex Systems Research Center)

    1993-03-01T23:59:59.000Z

    A small watershed of low relief in coastal New Hampshire was divided into hydrologic sub-areas in a geographic information system on the basis of soils, sub-basins and remotely-sensed landcover. Three variables were spatially modeled for input to 49 individual water-balances: available water content of the root zone, water input and potential evapotranspiration (PET). The individual balances were weight-summed to generate the aggregate watershed-balance, which saw 9% (48--50 mm) less annual actual-evapotranspiration (AET) compared to a lumped approach. Analysis of streamflow coefficients suggests that the spatially-distributed approach is more representative of the basin dynamics. Variation of PET by landcover accounted for the majority of the 9% AET reduction. Variation of soils played a near-negligible role. As a consequence of the above points, estimates of landcover proportions and annual PET by landcover are sufficient to correct a lumped water-balance in the Northeast. If remote sensing is used to estimate the landcover area, a sensor with a high spatial resolution is required. Finally, while the lower Thornthwaite model has conceptual limitations for distributed application, the upper Thornthwaite model is highly adaptable to distributed problems and may prove useful in many earth-system models.

  15. 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.

  16. Comparison of particle-tracking and lumped-parameter age-distribution models for evaluating vulnerability of production wells

    E-Print Network [OSTI]

    Groundwaterage . Contamination . Numerical modeling . Water supply . USA Introduction Drinking-water productionComparison of particle-tracking and lumped-parameter age-distribution models for evaluating-source contaminant inputs at the water table, some representation of the distribution of groundwater ages in the well

  17. Smoke inputs to climate models: optical properties and height distribution for nuclear winter studies

    SciTech Connect (OSTI)

    Penner, J.E.; Haselman, L.C. Jr.

    1985-04-01T23:59:59.000Z

    Smoke from fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in land surface temperatures. The extent of the decrease and even the sign of the temperature change depend on the optical characteristics of the smoke and how it is distributed with altitude. The height distribution of smoke over a fire is determined by the amount of buoyant energy produced by the fire and the amount of energy released by the latent heat of condensation of water vapor. The optical properties of the smoke depend on the size distribution of smoke particles which changes due to coagulation within the lofted plume. We present calculations demonstrating these processes and estimate their importance for the smoke source term input for climate models. For high initial smoke densities and for absorbing smoke ( m = 1.75 - 0.3i), coagulation of smoke particles within the smoke plume is predicted to first increase, then decrease, the size-integrated extinction cross section. However, at the smoke densities predicted in our model (assuming a 3% emission rate for smoke) and for our assumed initial size distribution, the attachment rates for brownian and turbulent collision processes are not fast enough to alter the smoke size distribution enough to significantly change the integrated extinction cross section. Early-time coagulation is, however, fast enough to allow further coagulation, on longer time scales, to act to decrease the extinction cross section. On these longer time scales appropriate to climate models, coagulation can decrease the extinction cross section by almost a factor of two before the smoke becomes well mixed around the globe. This process has been neglected in past climate effect evaluations, but could have a significant effect, since the extinction cross section enters as an exponential factor in calculating the light attenuation due to smoke. 10 refs., 20 figs.

  18. A simple model for the distribution of quiet Sun magnetic field strengths

    E-Print Network [OSTI]

    J. Sanchez Almeida

    2006-12-11T23:59:59.000Z

    We derive a first order linear differential equation describing the shape of the probability density function of magnetic field strengths in the quiet Sun (PDF). The modeling is very schematic. It considers convective motions which continuously supply and withdraw magnetic structures. In addition, a magnetic amplification mechanism increases the field strength up to a threshold that cannot be exceeded. These three basic ingredients provide PDFs in good agreement with the PDFs produced by realistic numerical simulations of magneto convection, as well as with quiet Sun PDFs inferred from observations. In particular, the distribution is approximately lognormal, and it produces an excess of magnetic fields (i.e., a 'hump' in the distribution) right before the maximum field strength. The success of this simple model may indicate that only a few basic ingredients shape the quiet Sun PDF. Our approach provides a concise parametric representation of the PDF, as required to develop automatic methods of diagnostics.

  19. Evaluating and developing parameter optimization and uncertainty analysis methods for a computationally intensive distributed hydrological model

    E-Print Network [OSTI]

    Zhang, Xuesong

    2009-05-15T23:59:59.000Z

    -7. Performance of PSO and PSO-SVM against model evaluations. .............. 117 Figure 7-1. Schematic illustration of one iteration of EMC.......................................... 126 Figure 7-2. Simulated values of the first and fifth component from the two...-modal distribution. The solid line is the true value, and the grey area is the density estimated by EMC. ......................................................................... 134 Figure 7-3. Scatter plot of the samples generated by EMC for the 20-modal...

  20. Homogenization of a catalyst layer model for periodically distributed pore geometries in PEM fuel cells

    E-Print Network [OSTI]

    Markus Schmuck; Peter Berg

    2012-04-30T23:59:59.000Z

    We formally derive an effective catalyst layer model comprising the reduction of oxygen for periodically distributed pore geometries. By assumption, the pores are completely filled with water and the surrounding walls consist of catalyst particles which are attached to an electron conducting microstructure. The macroscopic transport equations are established by a multi-scale approach, based on microscopic phenomena at the pore level, and serve as a first step toward future optimization of catalyst layer designs.

  1. Homogenization of a catalyst layer model for periodically distributed pore geometries in PEM fuel cells

    E-Print Network [OSTI]

    Schmuck, Markus

    2012-01-01T23:59:59.000Z

    We formally derive an effective catalyst layer model comprising the reduction of oxygen for periodically distributed pore geometries. By assumption, the pores are completely filled with water and the surrounding walls consist of catalyst particles which are attached to an electron conducting microstructure. The macroscopic transport equations are established by a multi-scale approach, based on microscopic phenomena at the pore level, and serve as a first step toward future optimization of catalyst layer designs.

  2. Model documentation natural gas transmission and distribution model (NGTDM) of the national energy modeling system. Volume II: Model developer`s report

    SciTech Connect (OSTI)

    Not Available

    1995-01-03T23:59:59.000Z

    To partially fulfill the requirements for {open_quotes}Model Acceptance{close_quotes} as stipulated in EIA Standard 91-01-01 (effective February 3, 1991), the Office of Integrated Analysis and Forecasting has conducted tests of the Natural Gas Transmission and Distribution Model (NGTDM) for the specific purpose of validating the forecasting model. This volume of the model documentation presents the results of {open_quotes}one-at-a-time{close_quotes} sensitivity tests conducted in support of this validation effort. The test results are presented in the following forms: (1) Tables of important model outputs for the years 2000 and 2010 are presented with respect to change in each input from the reference case; (2) Tables of percent changes from base case results for the years 2000 and 2010 are presented for important model outputs; (3) Tables of conditional sensitivities (percent change in output/percent change in input) for the years 2000 and 2010 are presented for important model outputs; (4) Finally, graphs presenting the percent change from base case results for each year of the forecast period are presented for selected key outputs. To conduct the sensitivity tests, two main assumptions are made in order to test the performance characteristics of the model itself and facilitate the understanding of the effects of the changes in the key input variables to the model on the selected key output variables: (1) responses to the amount demanded do not occur since there are no feedbacks of inputs from other NEMS models in the stand-alone NGTDM run. (2) All the export and import quantities from and to Canada and Mexico, and liquefied natural gas (LNG) imports and exports are held fixed (i.e., there are no changes in imports and exports between the reference case and the sensitivity cases) throughout the forecast period.

  3. Analytic model of the ion angular distribution in a collisional sheath

    SciTech Connect (OSTI)

    Vahedi, V.; Stewart, R.A.; Lieberman, M.A. (Department of Electrical Engineering and Computer Science and the Electronics Research Laboratory, University of California, Berkeley, Berkeley, California 94720 (United States))

    1993-07-01T23:59:59.000Z

    An analytic model is developed for the ion angular distribution in a collisional sheath. In a previous study, the one-dimensional (normal to the sheath) ion velocity distribution was obtained under the assumption that charge exchange is the dominant ion-neutral collision mechanism. In the present model, we assume [lambda][sub scat][ge][lambda][sub cx], where [lambda][sub scat] and [lambda][sub cx] are the mean free paths for ion-neutral elastic scattering and charge-exchange collisions, respectively. With this assumption, the angular distribution mainly arises from ions that strike the electrode after undergoing only one scattering collision following the last charge-exchange collision. Comparison of the analytic model with results obtained from a particle-in-cell simulation gives excellent agreement. Both the average angle of ions striking the electrode and the ratio of parallel to perpendicular ion flux at the electrode are shown to scale with the ratio of scattering to charge-exchange cross sections [sigma][sub scat]/[sigma][sub cx].

  4. Tracy-Widom asymptotics for a random polymer model with gamma-distributed weights

    E-Print Network [OSTI]

    Neil O'Connell; Janosch Ortmann

    2014-08-22T23:59:59.000Z

    We establish Tracy-Widom asymptotics for the partition function of a random polymer model with gamma-distributed weights recently introduced by Sepp\\"al\\"ainen. We show that the partition function of this random polymer can be represented within the framework of the geometric RSK correspondence and consequently its law can be expressed in terms of Whittaker functions. This leads to a representation of the law of the partition function which is amenable to asymptotic analysis. In this model, the partition function plays a role analogous to the smallest eigenvalue in the Laguerre unitary ensemble of random matrix theory.

  5. 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...

  6. Modeling of distribution and speciation of plutonium in the Urex extraction system

    SciTech Connect (OSTI)

    Paulenova, A.; Tkac, P. [Radiation Center, Oregon State University, Corvallis, OR 97331-5903 (United States); Vandegrift, G.F.; Krebs, J.F. [Argonne National Laboratory, Chemical Sciences and Engineering Division, Argonne, IL 60439-4837 (United States)

    2008-07-01T23:59:59.000Z

    The PUREX extraction process is used worldwide to recover uranium and plutonium from dissolved spent nuclear fuel using the tributylphosphate-nitric acid extraction system. In the recent decade, significant research progress was achieved with the aim to modify this system by addition of a salt-free agent to optimize stripping of plutonium from the tributylphosphate (TBP) extraction product (UREX). Experimental results on the extraction of Pu(IV) with and without acetohydroxamic acid in the HNO{sub 3}/TBP (30 vol %) were used for the development of a thermodynamic model of distribution and speciation of Pu(IV) in this separation process. Extraction constants for several sets of nitric acid, nitrate, and acetohydroxamic acid concentrations were used to model the obtained data. The extraction model AMUSE (Argonne Model for Universal Solvent Extraction) was employed in our calculations. (authors)

  7. Quasars Are Not Light-Bulbs: Testing Models of Quasar Lifetimes with the Observed Eddington Ratio Distribution

    E-Print Network [OSTI]

    Hopkins, Philip F

    2008-01-01T23:59:59.000Z

    We use the observed distribution of Eddington ratios as a function of supermassive black hole (BH) mass to constrain models of AGN lifetimes and lightcurves. Given the observed AGN luminosity function, a model for AGN lifetimes (time above a given luminosity) translates directly to a predicted Eddington ratio distribution. Models for self-regulated BH growth, in which feedback produces a 'blowout' decay phase after some peak luminosity (shutting down accretion) make specific predictions for the lifetimes distinct from those expected if AGN are simply gas starved (without feedback) and very different from simple phenomenological 'light bulb' models. Present observations of the Eddington ratio distribution, spanning 5 decades in Eddington ratio, 3 in BH mass, and redshifts z=0-1, agree with the predictions of self-regulated models, and rule out 'light-bulb', pure exponential, and gas starvation models at high significance. We compare the Eddington ratio distributions at fixed BH mass and fixed luminosity (both ...

  8. Sensitivity of Remote Aerosol Distributions to Representation of Cloud-Aerosol Interactions in a Global Climate Model

    SciTech Connect (OSTI)

    Wang, Hailong; Easter, Richard C.; Rasch, Philip J.; Wang, Minghuai; Liu, Xiaohong; Ghan, Steven J.; Qian, Yun; Yoon, Jin-Ho; Ma, Po-Lun; Vinoj, V.

    2013-06-05T23:59:59.000Z

    Many global aerosol and climate models, including the widely used Community Atmosphere Model version 5 (CAM5), have large biases in predicting aerosols in remote regions such as upper troposphere and high latitudes. In this study, we conduct CAM5 sensitivity simulations to understand the role of key processes associated with aerosol transformation and wet removal affecting the vertical and horizontal long-range transport of aerosols to the remote regions. Improvements are made to processes that are currently not well represented in CAM5, which are guided by surface and aircraft measurements together with results from a multi-scale aerosol-climate model (PNNL-MMF) that explicitly represents convection and aerosol-cloud interactions at cloud-resolving scales. We pay particular attention to black carbon (BC) due to its importance in the Earth system and the availability of measurements. We introduce into CAM5 a new unified scheme for convective transport and aerosol wet removal with explicit aerosol activation above convective cloud base. This new implementation reduces the excessive BC aloft to better simulate observed BC profiles that show decreasing mixing ratios in the mid- to upper-troposphere. After implementing this new unified convective scheme, we examine wet removal of submicron aerosols that occurs primarily through cloud processes. The wet removal depends strongly on the sub-grid scale liquid cloud fraction and the rate of conversion of liquid water to precipitation. These processes lead to very strong wet removal of BC and other aerosols over mid- to high latitudes during winter months. With our improvements, the Arctic BC burden has a10-fold (5-fold) increase in the winter (summer) months, resulting in a much better simulation of the BC seasonal cycle as well. Arctic sulphate and other aerosol species also increase but to a lesser extent. An explicit treatment of BC aging with slower aging assumptions produces an additional 30-fold (5-fold) increase in the Arctic winter (summer) BC burden. This BC aging treatment, however, has minimal effect on other under-predicted species. Interestingly, our modifications to CAM5 that aim at improving prediction of high-latitude and upper tropospheric aerosols also produce much better AOD and AAOD over various other regions globally when compared to multi-year AERONET retrievals. The improved aerosol distributions have impacts on other aspects of CAM5, improving the simulation of global mean liquid water path and cloud forcing.

  9. 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.

  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. Modeling studies of heat transfer and phase distribution in two-phase geothermal reservoirs

    SciTech Connect (OSTI)

    Lai, C.H.; Bodvarsson, G.S.; Truesdell, A.H. (Lawrence Berkeley Lab., CA (United States). Earth Sciences Div.)

    1994-02-01T23:59:59.000Z

    Phase distribution as well as mass flow and heat transfer behavior in two-phase geothermal systems have been studied by numerical modeling. A two-dimensional porous-slab model was used with a non-uniform heat flux boundary conditions at the bottom. Steady-state solutions are obtained for the phase distribution and heat transfer behavior for cases with different mass of fluid (gas saturation) in place, permeabilities, and capillary pressures. The results obtained show very efficient heat transfer in the vapor-dominated zone due to the development of heat pipes and near-uniform saturations. The phase distribution below the vapor-dominated zone depends on permeability. For relatively high-permeability systems, single-phase liquid zones prevail, with convection providing the energy throughput. For lower permeability systems, a two-phase liquid-dominated zone develops, because single-phase liquid convection is not sufficient to dissipate heat released from the source. These results are consistent with observations from the field, where most high-temperature liquid-dominated two-phase systems have relatively low permeabilities e.g. Krafla, Iceland; Kenya; Baca, New Mexico. The numerical results obtained also show that for high heat flow a high-temperature single-phase vapor zone can develop below a typical (240 C) vapor-dominated zone, as has recently been found at the Geysers, California, and Larderello, Italy.

  12. Generalized parton distribution functions and the nucleon spin sum rules in the chiral quark soliton model

    SciTech Connect (OSTI)

    Wakamatsu, M.; Tsujimoto, H. [Department of Physics, Faculty of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2005-04-01T23:59:59.000Z

    The theoretical predictions are given for the forward limit of the unpolarized spin-flip isovector generalized parton distribution function (E{sup u}-E{sup d})(x,{xi},t) within the framework of the chiral quark soliton model, with full inclusion of the polarization of Dirac sea quarks. We observe that [(H{sup u}-H{sup d})+(E{sup u}-E{sup d})](x,0,0) has a sharp peak around x=0, which we interpret as a signal of the importance of the pionic qq excitation with large spatial extension in the transverse direction. Another interesting indication given by the predicted distribution in combination with Ji's angular momentum sum rule is that the d quark carries more angular momentum than the u quark in the proton, which may have some relation with the physics of the violation of the Gottfried sum rule.

  13. 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.

  14. Transverse-momentum dependent parton distribution functions beyond leading twist in quark models

    E-Print Network [OSTI]

    C. Lorcé; B. Pasquini; P. Schweitzer

    2015-02-03T23:59:59.000Z

    Higher-twist transverse momentum dependent parton distribution functions (TMDs) are a valuable probe of the quark-gluon dynamics in the nucleon, and play a vital role for the explanation of sizable azimuthal asymmetries in hadron production from unpolarized and polarized deep-inelastic lepton-nucleon scattering observed in experiments at CERN, DESY and Jefferson Lab. The associated observables are challenging to interpret, and still await a complete theoretical explanation, which makes guidance from models valuable. In this work we establish the formalism to describe unpolarized higher-twist TMDs in the light-front framework based on a Fock-space expansion of the nucleon state in terms of free on-shell parton states. We derive general expressions and present numerical results in a practical realization of this picture provided by the light-front constituent quark model. We review several other popular quark model approaches including free quark ensemble, bag, spectator and chiral quark-soliton model. We discuss how higher-twist TMDs are described in these models, and obtain results for several TMDs not discussed previously in literature. This study contributes to the understanding of non-perturbative properties of subleading twist TMDs. The results from the light-front constituent quark model are also compared to available phenomenological information, showing a satisfactory agreement.

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. Quasars Are Not Light-Bulbs: Testing Models of Quasar Lifetimes with the Observed Eddington Ratio Distribution

    E-Print Network [OSTI]

    Philip F. Hopkins; Lars Hernquist

    2009-04-30T23:59:59.000Z

    We use the observed distribution of Eddington ratios as a function of supermassive black hole (BH) mass to constrain models of AGN lifetimes and lightcurves. Given the observed AGN luminosity function, a model for AGN lifetimes (time above a given luminosity) translates directly to a predicted Eddington ratio distribution. Models for self-regulated BH growth, in which feedback produces a 'blowout' decay phase after some peak luminosity (shutting down accretion) make specific predictions for the lifetimes distinct from those expected if AGN are simply gas starved (without feedback) and very different from simple phenomenological 'light bulb' models. Present observations of the Eddington ratio distribution, spanning 5 decades in Eddington ratio, 3 in BH mass, and redshifts z=0-1, agree with the predictions of self-regulated models, and rule out 'light-bulb', pure exponential, and gas starvation models at high significance. We compare the Eddington ratio distributions at fixed BH mass and fixed luminosity (both are consistent, but the latter are much less constraining). We present empirical fits to the lifetime distribution and show how the Eddington ratio distributions place tight limits on AGN lifetimes at various luminosities. We use this to constrain the shape of the typical AGN lightcurve, and provide simple analytic fits. Given independent constraints on episodic lifetimes, most local BHs must have gained their mass in no more than a couple of bright episodes, in agreement with merger-driven fueling models.

  2. A Monte Carlo study of the distribution of parameter estimators in a dual exponential decay model

    E-Print Network [OSTI]

    Garcia, Raul

    1969-01-01T23:59:59.000Z

    of an estimate of the reliability of the parameter estimates calculated. In 1965, Bell and Garcia [2] developed a computer program which permits a solution of the parameters without the time-consuming effort of manual calcu- lations. The same year, Rossing [3...A MONTE CARLO STUDY OF THE DISTRIBUTION OF PARAMETER ESTIMATORS IN A DUAL EXPONENTIAL DECAY MODEL A Thesis by SAUL GARCIA Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree...

  3. Extension of thermonuclear functions through the pathway model including Maxwell-Boltzmann and Tsallis distributions

    E-Print Network [OSTI]

    H. J. Haubold; D. Kumar

    2007-08-16T23:59:59.000Z

    The Maxwell-Boltzmannian approach to nuclear reaction rate theory is extended to cover Tsallis statistics (Tsallis, 1988) and more general cases of distribution functions. An analytical study of respective thermonuclear functions is being conducted with the help of statistical techniques. The pathway model, recently introduced by Mathai (2005), is utilized for thermonuclear functions and closed-form representations are obtained in terms of H-functions and G-functions. Maxwell-Boltzmannian thermonuclear functions become particular cases of the extended thermonuclear functions. A brief review on the development of the theory of analytic representations of nuclear reaction rates is given.

  4. 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...

  5. 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.

  6. Experimental measurements and numerical modeling of fast-ion distributions in the Alcator C-Mod Tokamak

    E-Print Network [OSTI]

    Bader, Aaron Craig

    2012-01-01T23:59:59.000Z

    In this thesis we discuss measurements and modeling of minority heated fast-ion distributions in the Ion Cyclotron Range of Frequencies (ICRF) on the Alcator C-Mod tokamak. Analysis of fast-ions >100Te is important for ...

  7. A Comparison Study of Collaborative Strategies for Distributed Defense against Internet Worms based on Small-World Modeling

    E-Print Network [OSTI]

    Chen, Yu

    based on Small-World Modeling Hao Chen, Yu Chen* Dept. of Electrical & Computer Engineering, SUNY threats to the network infrastructure. Distributed defense collaborating with single- point.0 vulnerability, mobile malware, industrial espionage, and attacks from organized crime. Malicious activities

  8. Spatial Ecology of the Giant Kangaroo Rat (Dipodomys ingens): A Test of Species Distribution Models as Ecological Revealers

    E-Print Network [OSTI]

    Bean, William Timothy

    2012-01-01T23:59:59.000Z

    biology. Trends in Ecology & Evolution 23:141-148. Kremen,simple habitat models. Ecology Letters 8:993-1009. Krebs, C.2008. Ecology: the experimental analysis of distribution and

  9. The use of a distributed hydrologic model to predict dynamic landslide susceptibility for a humid basin in Puerto Rico

    E-Print Network [OSTI]

    Kamal, Sameer A. (Sameer Ahmed)

    2009-01-01T23:59:59.000Z

    This thesis describes the use of a distributed hydrology model in conjunction with a Factor of Safety (FS) algorithm to predict dynamic landslide susceptibility for a humid basin in Puerto Rico. The Mameyes basin, located ...

  10. LandScan USA: A High Resolution Geospatial and Temporal Modeling Approach for Population Distribution and Dynamics

    SciTech Connect (OSTI)

    Bhaduri, Budhendra L [ORNL; Bright, Eddie A [ORNL; Coleman, Phil R [ORNL; Urban, Marie L [ORNL

    2007-01-01T23:59:59.000Z

    High resolution population distribution data are critical for successfully addressing important issues ranging from socio-environmental research to public health to homeland security, since scientific analyses, operational activities, and policy decisions are significantly influenced by the number of impacted people. Dasymetric modeling has been a well recognized approach for spatial decomposition of census data to increase the spatial resolution of population distribution. However, enhancing the temporal resolution of population distribution poses a greater challenge. In this paper, we discuss the development of LandScan USA, a multi-dimensional dasymetric modeling approach, which has allowed creation of very high resolution population distribution data both over space and time. At a spatial resolution of 3 arc seconds (~90m), the initial LandScan USA database contains both a nighttime residential as well as a baseline daytime population distribution that incorporates movement of workers and students. Challenging research issues of disparate and misaligned spatial data integration and modeling to develop a database at a national scale, as well as model verification and validation approaches are illustrated and discussed. Initial analyses indicate a high degree of accuracy for LandScan USA distribution model and data. High resolution population data such as LandScan USA, which describes both distribution and dynamics of human population, clearly has the potential to profoundly impact on multiple domain applications of national and global priority.

  11. 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.

  12. Distributed energy resources customer adoption modeling with combined heat and power applications

    SciTech Connect (OSTI)

    Siddiqui, Afzal S.; Firestone, Ryan M.; Ghosh, Srijay; Stadler, Michael; Edwards, Jennifer L.; Marnay, Chris

    2003-07-01T23:59:59.000Z

    In this report, an economic model of customer adoption of distributed energy resources (DER) is developed. It covers progress on the DER project for the California Energy Commission (CEC) at Berkeley Lab during the period July 2001 through Dec 2002 in the Consortium for Electric Reliability Technology Solutions (CERTS) Distributed Energy Resources Integration (DERI) project. CERTS has developed a specific paradigm of distributed energy deployment, the CERTS Microgrid (as described in Lasseter et al. 2002). The primary goal of CERTS distributed generation research is to solve the technical problems required to make the CERTS Microgrid a viable technology, and Berkeley Lab's contribution is to direct the technical research proceeding at CERTS partner sites towards the most productive engineering problems. The work reported herein is somewhat more widely applicable, so it will be described within the context of a generic microgrid (mGrid). Current work focuses on the implementation of combined heat and power (CHP) capability. A mGrid as generically defined for this work is a semiautonomous grouping of generating sources and end-use electrical loads and heat sinks that share heat and power. Equipment is clustered and operated for the benefit of its owners. Although it can function independently of the traditional power system, or macrogrid, the mGrid is usually interconnected and exchanges energy and possibly ancillary services with the macrogrid. In contrast to the traditional centralized paradigm, the design, implementation, operation, and expansion of the mGrid is meant to optimize the overall energy system requirements of participating customers rather than the objectives and requirements of the macrogrid.

  13. Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields

    SciTech Connect (OSTI)

    Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

    2009-11-30T23:59:59.000Z

    Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

  14. 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, ...

  15. 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)

  16. 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)

  17. 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).

  18. Modeling kinetic partitioning of secondary organic aerosol and size distribution dynamics: representing effects of volatility, phase state, and particle-phase reaction

    SciTech Connect (OSTI)

    Zaveri, Rahul A.; Easter, Richard C.; Shilling, John E.; Seinfeld, J. H.

    2014-05-27T23:59:59.000Z

    Evidence is mounting that the majority of the climatically active aerosols are produced through the growth of smaller particles via secondary organic aerosol (SOA) formation from gas-to-particle conversion of anthropogenic and biogenic volatile organic compounds (VOCs). The timescale of SOA partitioning and the associated size distribution dynamics are expected to depend on the gas-phase oxidation of the precursor VOCs and their products, volatility of these organic solutes, composition and phase state of the pre-existing particles, and diffusivity and reactivity of the solute within the particle phase. This paper describes a new framework for modeling kinetic gas-particle partitioning of SOA, with an analytical treatment for the diffusion-reaction process within the particle phase. The formulation is amenable for eventual use in regional and global climate models, although it currently awaits implementation of the actual particle-phase reactions that are important for SOA formation. In the present work, the model is applied to investigate the competitive growth dynamics of the Aitken and accumulation mode particles while the Kelvin effect and coagulation are neglected for simplicity. The timescale of SOA partitioning and evolution of number and composition size distributions are evaluated for a range of solute volatilities (C*), particle-phase bulk diffusivities (Db), and particle-phase reactivity, as exemplified by a pseudo-first-order rate constant (kc). Results show that irreversible condensation of non-volatile organic vapors (equivalent to ) produces significant narrowing of the size distribution. At the other extreme, non-reactive partitioning of semi-volatile organic vapors is volume-controlled in which the final (equilibrium) size distribution simply shifts to the right on the diameter axis while its shape remains unchanged. However, appreciable narrowing of the size distribution may occur when the pre-existing particles are highly viscous semi-solids such that small particles reach quasi-equilibrium much faster than the large ones. In the case of reactive partitioning (finite ), the size distribution experiences permanent narrowing, which is especially pronounced for Db < 10-13 cm2 s-1 and kc > 0.01 s-1. As a result, both number and composition size distributions are needed to effectively constrain and evaluate the next generation of SOA models that treat phase state thermodynamics, particle-phase diffusion and particle-phase chemical reactions.

  19. Modeling and mapping ferroresonant states in series compensated distribution and subtransmission lines

    SciTech Connect (OSTI)

    Barr, R.A. [Electric Power Consulting Pty Ltd., Culburra Beach, New South Wales (Australia)] [Electric Power Consulting Pty Ltd., Culburra Beach, New South Wales (Australia); Platt, D. [Univ. of Wollongong, New South Wales (Australia). Dept. of Electrical and Computer Engineering] [Univ. of Wollongong, New South Wales (Australia). Dept. of Electrical and Computer Engineering

    1996-04-01T23:59:59.000Z

    Series capacitors can increase the power carrying capacity of subtransmission and distribution lines by reducing voltage regulation. The potential exists in selected locations for utilities to both improve the customer quality of supply and increase the supply capacity. The possibility of ferroresonance and effective countermeasures to ferroresonance are important issues that need to be carefully considered at the design stage. Other design issues are capacitor location, ohmic reactive value, transient behavior, short circuit withstand and capacitor protection. Ferroresonance can cause severe overvoltages and heavy currents resulting in damage to power system equipment and customer installations. This paper describes a ferroresonance model incorporating both time domain and frequency domain techniques. The ferroresonance model is used to map the possible ferroresonant states. A small scale laboratory non-linear ferroresonant circuit was constructed with the experimental results comparing favorably with the predicted model behavior. For series compensated lines and other circuit arrangements, the ferroresonance model allows the prediction of ferroresonant states and the examination of counter measures.

  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. Distributed energy resources customer adoption modeling with combined heat and power applications

    E-Print Network [OSTI]

    Siddiqui, Afzal S.; Firestone, Ryan M.; Ghosh, Srijay; Stadler, Michael; Edwards, Jennifer L.; Marnay, Chris

    2003-01-01T23:59:59.000Z

    Alex Farrell of the Energy and Resources Group, UniversityMicrogrid Distributed Energy Resource Potential Using DER-of Distributed Energy Resources: The CERTS MicroGrid

  2. A hybrid model for particle transport and electron energy distributions in positive column electrical discharges using equivalent species transport

    E-Print Network [OSTI]

    Kushner, Mark

    A hybrid model for particle transport and electron energy distributions in positive column species are generated in the kinetic module. The hybrid model has been used to examine electron energy which has discrete negative energies representing bound states, and a positive continuum representing

  3. 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.

  4. 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...

  5. 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

  6. A stepped leader model for lightning including charge distribution in branched channels

    SciTech Connect (OSTI)

    Shi, Wei; Zhang, Li [School of Electrical Engineering, Shandong University, Jinan 250061 (China); Li, Qingmin, E-mail: lqmeee@ncepu.edu.cn [Beijing Key Lab of HV and EMC, North China Electric Power University, Beijing 102206 (China); State Key Lab of Alternate Electrical Power System with Renewable Energy Sources, Beijing 102206 (China)

    2014-09-14T23:59:59.000Z

    The stepped leader process in negative cloud-to-ground lightning plays a vital role in lightning protection analysis. As lightning discharge usually presents significant branched or tortuous channels, the charge distribution along the branched channels and the stochastic feature of stepped leader propagation were investigated in this paper. The charge density along the leader channel and the charge in the leader tip for each lightning branch were approximated by introducing branch correlation coefficients. In combination with geometric characteristics of natural lightning discharge, a stochastic stepped leader propagation model was presented based on the fractal theory. By comparing simulation results with the statistics of natural lightning discharges, it was found that the fractal dimension of lightning trajectory in simulation was in the range of that observed in nature and the calculation results of electric field at ground level were in good agreement with the measurements of a negative flash, which shows the validity of this proposed model. Furthermore, a new equation to estimate the lightning striking distance to flat ground was suggested based on the present model. The striking distance obtained by this new equation is smaller than the value estimated by previous equations, which indicates that the traditional equations may somewhat overestimate the attractive effect of the ground.

  7. Structure formation: a spherical model for the evolution of the density distribution

    E-Print Network [OSTI]

    P. Valageas

    1998-07-02T23:59:59.000Z

    Within the framework of hierarchical clustering we show that a simple Press-Schechter-like approximation, based on spherical dynamics, provides a good estimate of the evolution of the density field in the quasi-linear regime up to $\\Sigma \\sim 1$. Moreover, it allows one to recover the exact series of the cumulants of the probability distribution of the density contrast in the limit $\\Sigma \\to 0$ which sheds some light on the rigorous result and on ``filtering''. We also obtain similar results for the divergence of the velocity field. Next, we extend this prescription to the highly non-linear regime, using a stable-clustering approximation. Then we recover a specific scaling of the counts-in-cells which is indeed seen in numerical simulations, over a well-defined range. To this order we also introduce an explicit treatment of the behaviour of underdensities, which takes care of the normalization and is linked to the low-density bubbles and the walls one can see in numerical simulations. We compare this to a 1-dimensional adhesion model, and we present the consequences of our prescription for the power-law tail and the cutoff of the density distribution.

  8. 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

  9. 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

  10. 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

  11. Coupling Multi-Component Models with MPH on Distributed MemoryComputer Architectures

    SciTech Connect (OSTI)

    He, Yun; Ding, Chris

    2005-03-24T23:59:59.000Z

    A growing trend in developing large and complex applications on today's Teraflop scale computers is to integrate stand-alone and/or semi-independent program components into a comprehensive simulation package. One example is the Community Climate System Model which consists of atmosphere, ocean, land-surface and sea-ice components. Each component is semi-independent and has been developed at a different institution. We study how this multi-component, multi-executable application can run effectively on distributed memory architectures. For the first time, we clearly identify five effective execution modes and develop the MPH library to support application development utilizing these modes. MPH performs component-name registration, resource allocation and initial component handshaking in a flexible way.

  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. 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.

  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. 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. 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.

  17. 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.

  18. 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...

  19. 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

  20. 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

  1. 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.

  2. Distributed DBMS I Introduction

    E-Print Network [OSTI]

    Chen, Yangjun

    Distributed DBMS Outline I Introduction I Background I Distributed DBMS Architecture I Distributed Data server approach Parallel architectures Parallel DBMS techniques Parallel execution models Parallel Database Systems Distributed Object DBMS Database Interoperability Concluding Remarks #12

  3. 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.

  4. Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model

    SciTech Connect (OSTI)

    Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2010-12-23T23:59:59.000Z

    Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.

  5. 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

  6. 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.

  7. Minimizing Energy Consumption in a Water Distribution System: A Systems Modeling Approach

    E-Print Network [OSTI]

    Johnston, John

    2011-08-08T23:59:59.000Z

    In a water distribution system from groundwater supply, the bulk of energy consumption is expended at pump stations. These pumps pressurize the water and transport it from the aquifer to the distribution system and to elevated storage tanks. Each...

  8. A model-based approach to regulating electricity distribution under new operating conditions

    E-Print Network [OSTI]

    Yap, Xiang Ling

    2012-01-01T23:59:59.000Z

    New technologies such as distributed generation and electric vehicles are connecting to the electricity distribution grid, a regulated natural monopoly. Existing regulatory schemes were not designed for these new technologies ...

  9. 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.

  10. 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.

  11. Distributed energy resources in practice: A case study analysis and validation of LBNL's customer adoption model

    SciTech Connect (OSTI)

    Bailey, Owen; Creighton, Charles; Firestone, Ryan; Marnay, Chris; Stadler, Michael

    2003-02-01T23:59:59.000Z

    This report describes a Berkeley Lab effort to model the economics and operation of small-scale (<500 kW) on-site electricity generators based on real-world installations at several example customer sites. This work builds upon the previous development of the Distributed Energy Resource Customer Adoption Model (DER-CAM), a tool designed to find the optimal combination of installed equipment, and idealized operating schedule, that would minimize the site's energy bills, given performance and cost data on available DER technologies, utility tariffs, and site electrical and thermal loads over a historic test period, usually a recent year. This study offered the first opportunity to apply DER-CAM in a real-world setting and evaluate its modeling results. DER-CAM has three possible applications: first, it can be used to guide choices of equipment at specific sites, or provide general solutions for example sites and propose good choices for sites with similar circumstances; second, it can additionally provide the basis for the operations of installed on-site generation; and third, it can be used to assess the market potential of technologies by anticipating which kinds of customers might find various technologies attractive. A list of approximately 90 DER candidate sites was compiled and each site's DER characteristics and their willingness to volunteer information was assessed, producing detailed information on about 15 sites of which five sites were analyzed in depth. The five sites were not intended to provide a random sample, rather they were chosen to provide some diversity of business activity, geography, and technology. More importantly, they were chosen in the hope of finding examples of true business decisions made based on somewhat sophisticated analyses, and pilot or demonstration projects were avoided. Information on the benefits and pitfalls of implementing a DER system was also presented from an additional ten sites including agriculture, education, health care, airport, and manufacturing facilities.

  12. 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

  13. 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

  14. 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.

  15. M. Steffen et al.: Hydrodynamical Models of Circumstellar Dust Shells 5 Figure 3. Top: Time sequence of spectral energy distributions computed from our oxygen

    E-Print Network [OSTI]

    sequence of spectral energy distributions computed from our oxygen star model with a dust shell composed.: Hydrodynamical Models of Circumstellar Dust Shells Figure 2. Top: Time sequence of spectral energy distributionsM. Steffen et al.: Hydrodynamical Models of Circumstellar Dust Shells 5 Figure 3. Top: Time

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. Abstract--A physically based, spatially-distributed water quality model is being developed to simulate spatial and temporal

    E-Print Network [OSTI]

    Abstract--A physically based, spatially-distributed water quality model is being developed, and water quality were used to estimate nonpoint source loading potential in the study watersheds. Animal to the monitored total phosphorous load indicates that both point and nonpoint sources are major contributors

  1. Retrospective modeling of the merit-order effect on wholesale electricity prices from distributed photovoltaic generation in the

    E-Print Network [OSTI]

    Sandiford, Mike

    Retrospective modeling of the merit-order effect on wholesale electricity prices from distributed, the depression in wholesale prices has significant value. c 5 GW of solar generation would have saved $1.8 billion in the market over two years. c The depression of wholesale prices offsets the cost of support

  2. Distributed delay model for density wave dynamics in gas lifted wells Laure Sin`egre, Nicolas Petit

    E-Print Network [OSTI]

    Distributed delay model for density wave dynamics in gas lifted wells Laure Sin`egre, Nicolas Petit in the tubing D. dynamical choking is used to stabilise the density wave instability. In this paper, we propose instabilities cause production losses. One of these instabilities, referred to as the "density-wave

  3. A controlled distributed parameter model for a fluid-flexible structure system: numerical simulations and experiment validations

    E-Print Network [OSTI]

    Baudouin, Lucie

    A controlled distributed parameter model for a fluid-flexible structure system: numerical consider the problem of active reduction of vibrations in a fluid-flexible structure system and the sloshing of the fuel inside the wing's tank. The control is performed using piezoelectric patches

  4. Mining for Availability Models in Large-Scale Distributed Systems: A Case Study of SETI@home

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Mining for Availability Models in Large-Scale Distributed Systems: A Case Study of SETI@home Bahman. Invariably, these systems are composed of heterogeneous hosts whose indi- vidual availability often exhibit describe an effective method for discovering subsets of hosts whose availability have similar statistical

  5. Mining for Statistical Models of Availability in Large-Scale Distributed Systems: An Empirical Study of SETI@home

    E-Print Network [OSTI]

    Kondo, Derrick

    Mining for Statistical Models of Availability in Large-Scale Distributed Systems: An Empirical, these systems are composed of heterogeneous hosts whose individual availability often exhibit different an effective method for discovering subsets of hosts whose availability have similar statistical properties

  6. An Energy-Aware Simulation Model and Transaction Protocol for Dynamic Workload Distribution in Mobile Ad Hoc Networks1

    E-Print Network [OSTI]

    Pedram, Massoud

    An Energy-Aware Simulation Model and Transaction Protocol for Dynamic Workload Distribution an energy-aware network transaction protocol that dynamically redistributes the computational workload among for detailed evaluation of the performance of different energy management policies in a MANET. Next it presents

  7. 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

  8. 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...

  9. 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

  10. 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

  11. The Spatial Clustering of ROSAT All-Sky Survey AGNs II. Halo Occupation Distribution Modeling of the Cross Correlation Function

    E-Print Network [OSTI]

    Miyaji, Takamitsu; Coil, Alison L; Aceves, Hector

    2010-01-01T23:59:59.000Z

    This is the second paper of a series that reports on our investigation of the clustering properties of AGNs in the ROSAT All-Sky Survey (RASS) through cross-correlation functions (CCFs) with Sloan Digital Sky Survey (SDSS) galaxies. In this paper, we apply the Halo Occupation Distribution (HOD) model to the CCFs between the RASS Broad-line AGNs with SDSS Luminous Red Galaxies (LRGs) in the redshift range 0.16modeling approach, we use the known HOD of LRGs and constrain the HOD of the AGNs by a model fit to the CCF. For the first time, we are able to go beyond quoting merely a `typical' AGN host halo mass, M_h, and model the full distribution function of AGN host dark matter halos. In addition, we are able to determine the large-scale bias and the mean M_h more accurately. We explore the behavior of three simple HOD models. Our first model (Model A) is a truncated power-law HOD model in which all AGNs are satellites. With this model, we find an upper lim...

  12. 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)

  13. Calibration of a distributed flood forecasting model with input uncertainty using a Bayesian framework

    E-Print Network [OSTI]

    Li, M.

    2013-01-01T23:59:59.000Z

    error model for calibration and uncertainty estimation ofand T. Wagener (2005), Model calibration and uncertaintyand A. Mailhot (2008), Calibration of hydrological model

  14. Energy performance of underfloor air distribution systems part IV: underfloor plenum testing and modeling

    E-Print Network [OSTI]

    Bauman, Fred; Jin, Hui

    2007-01-01T23:59:59.000Z

    simulation, five heat transfer model options are possible.fluid dependent. The heat transfer model selected for theapplications. The heat transfer model is used to predict the

  15. Global distribution and climate forcing of marine organic aerosol: 1. Model improvements and evaluation

    SciTech Connect (OSTI)

    Meskhidze, N.; Xu, J.; Gantt, Brett; Zhang, Yang; Nenes, Athanasios; Ghan, Steven J.; Liu, Xiaohong; Easter, Richard C.; Zaveri, Rahul A.

    2011-11-23T23:59:59.000Z

    Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM5) with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7). Emissions of marine primary organic aerosols (POA), phytoplanktonproduced isoprene- and monoterpenes-derived secondary organic aerosols (SOA) and methane sulfonate (MS{sup -}) are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr{sup -1}, for the Gantt et al. (2011) and Vignati et al. (2010) emission parameterizations, respectively. Marine sources of SOA and particulate MS{sup -} (containing both sulfur and carbon atoms) contribute an additional 0.2 and 5.1 Tg yr{sup -1}, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ngm{sup -3}, with values up to 400 ngm{sup -3} over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM) with POA concentrations from the two emission parameterizations shows that despite revealed discrepancies (often more than a factor of 2), both Gantt et al. (2011) and Vignati et al. (2010) formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011) parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN). The largest increases (up to 20 %) in CCN (at a supersaturation (S) of 0.2 %) number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming marine organics are internally-mixed with sea-salt provides diverse results with increases and decreases in the concentration of CCN over different parts of the ocean. The sign of the CCN change due to the addition of marine organics to seasalt aerosol is determined by the relative significance of the increase in mean modal diameter due to addition of mass, and the decrease in particle hygroscopicity due to compositional changes in marine aerosol. Based on emerging evidence for increased CCN concentration over biologically active surface ocean areas/periods, our study suggests that treatment of sea spray in global climate models (GCMs) as an internal mixture of marine organic aerosols and sea-salt will likely lead to an underestimation in CCN number concentration.

  16. 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...

  17. 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 ...

  18. 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.

  19. 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.

  20. Coupling Multi-Component Models with MPH on Distributed Memory Computer Architectures

    E-Print Network [OSTI]

    He, Yun; Ding, Chris

    2005-01-01T23:59:59.000Z

    Among these, NASA’s Earth System Models Framework (ESMF) [to facilitate coupling earth system model components and to

  1. 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...

  2. Service and Utility Oriented Distributed Computing Systems: Challenges and Opportunities for Modeling and Simulation Communities

    E-Print Network [OSTI]

    Buyya, Rajkumar

    1 Service and Utility Oriented Distributed Computing Systems: Challenges and Opportunities) networks have emerged as popular platforms for the next generation parallel and distributed computing. Utility computing is envisioned to be the next generation of IT evolution that depicts how computing needs

  3. Inclusive distributions at the LHC as predicted from the DPMJET-III model with chain fusion

    E-Print Network [OSTI]

    J. Ranft; F. W. Bopp; R. Engel; S. Roesler

    2007-06-26T23:59:59.000Z

    DPMJET-III with chain fusion is used to calculate inclusive distributions of Pb-Pb collisions at LHC energies. We present rapidity distributions as well as scaled multiplicities at mid-rapidity as function of the collision energy and the number of participants.

  4. DISTRIBUTION AND RANGE OF RADIONUCLIDE SORPTIOIN COEFFICIENTS IN A SAVANNAH RIVER SITE SUBSURFACE: STOCHASTIC MODELING CONSIDERATIONS - 10259

    SciTech Connect (OSTI)

    Kaplan, D.

    2010-01-04T23:59:59.000Z

    The uncertainty associated with the sorption coefficient, or K{sub d} value, is one of the key uncertainties in estimating risk associated with burying low-level nuclear waste in the subsurface. The objective of this study was to measure >648 K{sub d} values and provide a measure of the range and distribution (normal or log-normal) of radionuclide K{sub d} values appropriate for the E-Area disposal site, within the Savannah River Site, near Aiken South Carolina. The 95% confidence level for the mean K{sub d} was twice the mean in the Aquifer Zone (18-30.5 m depth), equal to the mean for the Upper Vadose Zone (3.3-10 m depth), and half the mean for the Lower Vadose Zone (3.3-18 m depth). The distribution of K{sub d} values was log normal in the Upper Vadose Zone and Aquifer Zone, and normal in the Lower Vadose Zone. To our knowledge, this is the first report of natural radionuclide K{sub d} variability in the literature. Using ranges and distribution coefficients that are specific to the hydrostratigraphic unit improved model accuracy and reduced model uncertainty. Unfortunately, extension of these conclusions to other sites is likely not appropriate given that each site has its own sources of hydrogeological variability. However, this study provides one of the first examples of the development stochastic ranges and distributions of K{sub d} values for a hydrological unit for stochastic modeling.

  5. Analytical modeling of AlGaN/AlN/GaN heterostructures including effects of distributed surface donor states

    SciTech Connect (OSTI)

    Goyal, Nitin, E-mail: nitin@unik.no [Carinthian Tech Research CTR AG, Europastraße 4/1, Technologiepark Villach, A-9524 Villach/St. Magdalen (Austria); Department of Electronics and Telecommunication, Norwegian University of Science and Technology, Trondheim NO7034 (Norway); Fjeldly, Tor A. [Department of Electronics and Telecommunication, Norwegian University of Science and Technology, Trondheim NO7034 (Norway)

    2014-07-14T23:59:59.000Z

    In this paper, a physics based analytical model is presented for calculation of the two-dimensional electron gas density and the bare surface barrier height of AlGaN/AlN/GaN material stacks. The presented model is based on the concept of distributed surface donor states and the self-consistent solution of Poisson equation at the different material interfaces. The model shows good agreement with the reported experimental data and can be used for the design and characterization of advanced GaN devices for power and radio frequency applications.

  6. Photoelectron angular distributions for states of any mixed character: An experiment-friendly model for atomic, molecular, and cluster anions

    SciTech Connect (OSTI)

    Khuseynov, Dmitry; Blackstone, Christopher C.; Culberson, Lori M.; Sanov, Andrei, E-mail: sanov@u.arizona.edu [Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721 (United States)

    2014-09-28T23:59:59.000Z

    We present a model for laboratory-frame photoelectron angular distributions in direct photodetachment from (in principle) any molecular orbital using linearly polarized light. A transparent mathematical approach is used to generalize the Cooper-Zare central-potential model to anionic states of any mixed character. In the limit of atomic-anion photodetachment, the model reproduces the Cooper-Zare formula. In the case of an initial orbital described as a superposition of s and p-type functions, the model yields the previously obtained s-p mixing formula. The formalism is further advanced using the Hanstorp approximation, whereas the relative scaling of the partial-wave cross-sections is assumed to follow the Wigner threshold law. The resulting model describes the energy dependence of photoelectron anisotropy for any atomic, molecular, or cluster anions, usually without requiring a direct calculation of the transition dipole matrix elements. As a benchmark case, we apply the p-d variant of the model to the experimental results for NO{sup ?} photodetachment and show that the observed anisotropy trend is described well using physically meaningful values of the model parameters. Overall, the presented formalism delivers insight into the photodetachment process and affords a new quantitative strategy for analyzing the photoelectron angular distributions and characterizing mixed-character molecular orbitals using photoelectron imaging spectroscopy of negative ions.

  7. Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine

    SciTech Connect (OSTI)

    Makhkamov, K.K.; Ingham, D.B.

    1999-11-01T23:59:59.000Z

    A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.

  8. ERB and Northern European FRIEND Project 5 Conference, Demnovsk dolina, Slovakia, 2002 Evaluation of a distributed hydrology model to support restoration

    E-Print Network [OSTI]

    Walter, M.Todd

    of a distributed hydrology model to support restoration efforts in small watersheds with limited data: from to assist in decision making. Distributed hydrologic modeling in geographic information systems (GIS) has scale, or they require excessive calibration, or they are not based on the dominant hydrologic processes

  9. Quantifying Fluid Distribution and Phase Connectivity with a Simple 3D Cubic Pore Network Model Constrained by NMR and MICP Data

    E-Print Network [OSTI]

    Torres-Verdín, Carlos

    1 Quantifying Fluid Distribution and Phase Connectivity with a Simple 3D Cubic Pore Network Model; Nuclear Magnetic Resonance; Pore Network; Invasion Percolation; Fluid Distribution; Relative Permeability Constrained by NMR and MICP Data Chicheng Xu1 and Carlos Torres-Verdín2 Running Head: Pore Network Modeling

  10. A model for the directional distribution of the diffuse sky radiance with an application to a CPC collector

    SciTech Connect (OSTI)

    Siala, F.M.F. (Center for Solar Energy Studies, Tripoli (Libya)); Hooper, F.C. (Univ. of Toronto, Ontario (Canada))

    1990-01-01T23:59:59.000Z

    The development of a new, semi-empirical model for the directional distribution of the diffuse radiance is reported. The proposed regression-type model, with the form of its base functions obtained from physical principles, is based on a combination of the purely physical reasoning approach and the purely empirical approach. Direct multiple-scattering calculations are circumvented through the use of the method of successive orders of scattering. The model is calibrated for the mean diffuse radiance estimated under all sky conditions reported in a large and comprehensive diffuse radiance data set. It is found that only a small increase in accuracy is gained by including higher orders of scattering, and this increase does not justify the complexity of the resulting model. Therefore, the single scattering approximation is recommended. The use of the model is illustrated in a typical application, in which the fraction of diffuse radiation intercepted by the receive of a compound parabolic concentrator is computed.

  11. 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.

  12. Resonance recombination model and quark distribution functions in the quark-gluon plasma

    E-Print Network [OSTI]

    Ravagli, L.; van Hees, H.; Rapp, Ralf.

    2009-01-01T23:59:59.000Z

    We investigate the consequences of space-momentum correlations in quark phase-space distributions for coalescence processes at the hadronization transition. Thus far it has been proved difficult to reconcile such correlations with the empirically...

  13. Path delay model based on -stable distribution for the 60GHz indoor channel.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    monolithic microwave integrated circuit (MMIC) transmitters and receivers will make possible the use of hand present the statistical results of fitting the delays to -stable distributions. In the third section

  14. DistFlow ODE: Modeling, analyzing and controlling long distribution feeder

    E-Print Network [OSTI]

    Wang, Danhua

    We consider a linear feeder connecting multiple distributed loads and generators to the sub-station. Voltage is controlled directly at the sub-station, however, voltage down the line shifts up or down, in particular depending ...

  15. Load Modeling and State Estimation Methods for Power Distribution Systems: Final Report

    SciTech Connect (OSTI)

    Tom McDermott

    2010-05-07T23:59:59.000Z

    The project objective was to provide robust state estimation for distribution systems, comparable to what has been available on transmission systems for decades. This project used an algorithm called Branch Current State Estimation (BCSE), which is more effective than classical methods because it decouples the three phases of a distribution system, and uses branch current instead of node voltage as a state variable, which is a better match to current measurement.

  16. Interpretation of models of fundamental ecological niches and species' distributional areas

    E-Print Network [OSTI]

    Soberó n, Jorge

    2005-01-01T23:59:59.000Z

    , realizad niche, geographic distribution The fact that, at certain scales, climatic and physical factors affect profoundly the distributions of species has been known for a very long time. In the last two decades, mathematical techniques designed... to estimate the geographic extent of the “fundamental ecological niche” (FN), or subsets of it, defined mostly in coarse-scale climatic dimensions [the “bioclimatic envelope” or climatic niche (Pearson & Dawson 2003)], have seen increasing use. Although...

  17. Verifying Distributed Real-time Properties of Embedded Systems via Graph Transformations and Model Checking

    E-Print Network [OSTI]

    Abdelwahed, Sherif

    S properties, such as low latency, low energy consumption, bounded jitter, high reliability, high throughput and data acquisition (SCADA) systems that manage regional power grids. Key un- resolved challenges include

  18. Optimal capacitor placement, replacement and control in large-scale unbalanced distribution systems: System modeling and a new formulation

    SciTech Connect (OSTI)

    Chiang, H.D.; Wang, J.C.; Tong, J. [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering; Darling, G. [NYSEG Corp., Binghamton, NY (United States). Distribution System Dept.

    1995-02-01T23:59:59.000Z

    This paper undertakes the problem of optimal capacitor placement, replacement and control in large-scale unbalanced, radial or loop distribution networks. The problem is how to optimally determine the locations to install (or replace, or remove) capacitors, the types and sizes of capacitors to be installed (or replaced) and, during each load level, the control schemes for each capacitor in the nodes of a general three-phase unbalanced distribution system such that a desired objective function is minimized while the load constraints, network constraints and operational constraints (e.g. the voltage profile) at different load levels are satisfied. The objective function considered consists of two terms: cost for energy loss and cost related to capacitor purchase, capacitor installation, capacitor replacement and capacitor removal. Comprehensive modelings of different components are presented which include primary power networks, three-phase transformers (different winding connections, off-nominal tap ratio, core and copper losses), co-generators, voltage sensitive load models for single-phase, two-phase and three-phase loads, shunt capacitors and reactors. The new problem is formulated as a combinatorial optimization problem with a non-differentiable objective function. The configuration space essential in the design of an annealing-based solution methodology for the new problem is derived. An effective solution methodology for solving the new problem and numerical studies on a realistic, unbalanced distribution network, a 291-bus with 305 distribution lines and 6 transformers, with varying loading conditions, will be presented in a companion paper.

  19. Optimal capacitor placement, replacement and control in large-scale unbalanced distribution systems: System modeling and a new formulation

    SciTech Connect (OSTI)

    Chiang, H.D.; Wang, J.C.; Tong, J. [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering; Darling, G. [NYSEG Corp., Binghamton, NY (United States). Distribution System Dept.

    1994-12-31T23:59:59.000Z

    This paper undertakes the problem of optimal capacitor placement, replacement and control in large-scale unbalanced, radial or loop distribution networks. The problem is how to optimally determine the locations to install (or replace, or remove) capacitors, the types and sizes of capacitors to be installed (or replaced) and, during each load level, the control schemes for each capacitor in the nodes of a general three-phase unbalanced distribution system such that a desired objective function is minimized while the load constraints, network constraints and operational constraints (e.g. the voltage profile) at different load levels are satisfied. The objective function considered consists of two terms: cost for energy loss and cost related to capacitor purchase, capacitor installation, capacitor replacement and capacitor removal. Comprehensive modelings of different components are presented which include primary power networks, three-phase transformers (different winding connections, off-nominal tap ratio, core and copper losses), co-generators, voltage sensitive load models for single-phase, two-phase and three-phase loads, shunt capacitors and rectors. The new problem is formulated as a combinational optimization problem with a non-differentiable objective function. The configuration space essential in the design of a annealing-based solution methodology for solving the new problem and numerical studies on a realistic, unbalanced distribution network, a 291-bus with 305 distribution lines and 6 transformers, with varying loading conditions, will be presented in a companion paper.

  20. Application of Distribution Transformer Thermal Life Models to Electrified Vehicle Charging Loads Using Monte-Carlo Method: Preprint

    SciTech Connect (OSTI)

    Kuss, M.; Markel, T.; Kramer, W.

    2011-01-01T23:59:59.000Z

    Concentrated purchasing patterns of plug-in vehicles may result in localized distribution transformer overload scenarios. Prolonged periods of transformer overloading causes service life decrements, and in worst-case scenarios, results in tripped thermal relays and residential service outages. This analysis will review distribution transformer load models developed in the IEC 60076 standard, and apply the model to a neighborhood with plug-in hybrids. Residential distribution transformers are sized such that night-time cooling provides thermal recovery from heavy load conditions during the daytime utility peak. It is expected that PHEVs will primarily be charged at night in a residential setting. If not managed properly, some distribution transformers could become overloaded, leading to a reduction in transformer life expectancy, thus increasing costs to utilities and consumers. A Monte-Carlo scheme simulated each day of the year, evaluating 100 load scenarios as it swept through the following variables: number of vehicle per transformer, transformer size, and charging rate. A general method for determining expected transformer aging rate will be developed, based on the energy needs of plug-in vehicles loading a residential transformer.

  1. 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.

  2. Pretzelosity distribution function

    E-Print Network [OSTI]

    H. Avakian; A. V. Efremov; P. Schweitzer; F. Yuan

    2008-08-28T23:59:59.000Z

    The 'pretzelosity' distribution is discussed. Theoretical properties, model results, and perspectives to access experimental information on this leading twist, transverse momentum dependent parton distribution function are reviewed. Its relation to helicity and transversity distributions is highlighted.

  3. 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.

  4. Improved Indoor Tracking Based on Generalized t-Distribution Noise Model

    E-Print Network [OSTI]

    Shuo, Liu; Le, Yin; Khuen, Ho Weng; Voon, Ling Keck

    2015-01-01T23:59:59.000Z

    objective function. Industrial & engineering chemistryfunction approac. Industrial & Engineering Chem- istrynoise model. Industrial & Engineering Chemistry Research,

  5. Economic regulation of electricity distribution utilities under high penetration of distributed energy resources : applying an incentive compatible menu of contracts, reference network model and uncertainty mechanisms

    E-Print Network [OSTI]

    Jenkins, Jesse D. (Jesse David)

    2014-01-01T23:59:59.000Z

    Ongoing changes in the use and management of electricity distribution systems - including the proliferation of distributed energy resources, smart grid technologies (i.e., advanced power electronics and information and ...

  6. Validation of a Fast-Fluid-Dynamics Model for Predicting Distribution of Particles with Low Stokes Number

    SciTech Connect (OSTI)

    Zuo, Wangda; Chen, Qingyan

    2011-06-01T23:59:59.000Z

    To design a healthy indoor environment, it is important to study airborne particle distribution indoors. As an intermediate model between multizone models and computational fluid dynamics (CFD), a fast fluid dynamics (FFD) model can be used to provide temporal and spatial information of particle dispersion in real time. This study evaluated the accuracy of the FFD for predicting transportation of particles with low Stokes number in a duct and in a room with mixed convection. The evaluation was to compare the numerical results calculated by the FFD with the corresponding experimental data and the results obtained by the CFD. The comparison showed that the FFD could capture major pattern of particle dispersion, which is missed in models with well-mixed assumptions. Although the FFD was less accurate than the CFD partially due to its simplification in numeric schemes, it was 53 times faster than the CFD.

  7. 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.

  8. 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.

  9. Distributed Energy: Modeling Penetration in Industrial Sector Over the Long-Term

    E-Print Network [OSTI]

    Greening, L.

    2006-01-01T23:59:59.000Z

    -established industrial energy model, ITEMS (Industrial Technology and Energy Modeling System), and is calibrated to MECS 1994 and 1998. However, as compared to ITEMS, MARKAL is an optimization framework. And, this particular version of MARKAL has a forecast horizon...

  10. In-situ prediction on sensor networks using distributed multiple linear regression models

    E-Print Network [OSTI]

    Basha, Elizabeth (Elizabeth Ann)

    2010-01-01T23:59:59.000Z

    Within sensor networks for environmental monitoring, a class of problems exists that requires in-situ control and modeling. In this thesis, we provide a solution to these problems, enabling model-driven computation where ...

  11. A Distributed Multi-User Role-Based Model Integration Framework

    SciTech Connect (OSTI)

    Dorow, Kevin E.; Gorton, Ian; Thurman, David A.

    2004-06-14T23:59:59.000Z

    Integrated computational modeling can be very useful in making quick, yet informed decisions related to environmental issues including Brownfield assessments. Unfortunately, the process of creating meaningful information using this methodology is fraught with difficulties, particularly when multiple computational models are required. Common problems include the inability to seamlessly transfer information between models, the difficulty of incorporating new models and integrating heterogeneous data sources, executing large numbers of model runs in a reasonable time frame, and adequately capturing pedigree information that describes the specific computational steps and data required to reproduce results. While current model integration frameworks have successfully addressed some of these problems, none have addressed all of them. Building on existing work at Pacific Northwest National Laboratory (PNNL), we have created an extensible software architecture for the next generation of model integration frameworks that addresses these issues. This paper describes this architecture that is being developed to support integrated water resource modeling in a metropolitan area.

  12. 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.

  13. Modeling and Management of Distributed Applications and Services Using the OSI Management Framework \\Lambda

    E-Print Network [OSTI]

    Katchabaw, Michael James

    networks and their devices. This paper describes our work investigating the use of the OSI Management, management interface instrumentation, management applications] \\Lambda This research work is supported are not ``equipped'' to be managed. Our recent work has focused on the management of distributed applications

  14. Fluid models for evaluating threshold-based control policies for survivability of a distributed network

    E-Print Network [OSTI]

    Gautam, Natarajan

    in change of work load characteristics. Therefore, the resource sharing mechanism must be robust to work Abstract The objective of this paper is to develop methods to improve the survivability of a distributed by the agent on the machine but also by other applications running on the machine. Based on the load

  15. Assessment of environmental correlates with the distribution of fish stocks using a spatially explicit model

    E-Print Network [OSTI]

    Robinson, Allan R.

    Assessment of environmental correlates with the distribution of fish stocks using a spatially-mail: msundermeyer@umassd.edu phone: (508) 999-8812 fax: (508) 910-6371 Running title: Assessing environmental;INTRODUCTION We present here a method for assessing the explanatory skill of environmental correlates

  16. The Discrete Infinite Logistic Normal Distribution for Mixed-Membership Modeling

    E-Print Network [OSTI]

    Blei, David M.

    , Chong Wang and David Blei Department of Computer Science, Princeton University {jpaisley,chongw,blei) (Blei et al., 2003) to allow each group of data (e.g., document) to be modeled as a mix- ture over. To address this issue in the finite LDA model, Blei & Lafferty (2007) introduced the correlated topic model

  17. Matilda: A Distributed UML Virtual Machine for Model-Driven Software Development

    E-Print Network [OSTI]

    Suzuki, Jun

    is designed as a pipeline (or sequence) of plugins. Different plugins implement different functionalities in Matilda, such as importing UML models, validating UML models and construct- ing a JAST. The pipeline, called Matilda, which allows developers to design their applications as UML models and directly execute

  18. Quantification of model mismatch errors of the dynamic energy distribution in a stirred-tank reactor 

    E-Print Network [OSTI]

    Kimmich, Mark Raymond

    1987-01-01T23:59:59.000Z

    stream and the recycle stream. Both streams were modeled as plug flow. The model was developed for tanks using axial flow agitators with a large length/diameter ratio. Tracer experiments were used to validate the model. Based on difFerent tracer...

  19. 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.

  20. Experimental determination of the radial dose distribution in high gradient regions around {sup 192}Ir wires: Comparison of electron paramagnetic resonance imaging, films, and Monte Carlo simulations

    SciTech Connect (OSTI)

    Kolbun, N.; Leveque, Ph.; Abboud, F.; Bol, A.; Vynckier, S.; Gallez, B. [Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium); Molecular Imaging and Experimental Radiotherapy Unit, Institute of Experimental and Clinical Research, Universite catholique de Louvain, Avenue Hippocrate 55, B-1200 Brussels (Belgium); Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium)

    2010-10-15T23:59:59.000Z

    Purpose: The experimental determination of doses at proximal distances from radioactive sources is difficult because of the steepness of the dose gradient. The goal of this study was to determine the relative radial dose distribution for a low dose rate {sup 192}Ir wire source using electron paramagnetic resonance imaging (EPRI) and to compare the results to those obtained using Gafchromic EBT film dosimetry and Monte Carlo (MC) simulations. Methods: Lithium formate and ammonium formate were chosen as the EPR dosimetric materials and were used to form cylindrical phantoms. The dose distribution of the stable radiation-induced free radicals in the lithium formate and ammonium formate phantoms was assessed by EPRI. EBT films were also inserted inside in ammonium formate phantoms for comparison. MC simulation was performed using the MCNP4C2 software code. Results: The radical signal in irradiated ammonium formate is contained in a single narrow EPR line, with an EPR peak-to-peak linewidth narrower than that of lithium formate ({approx}0.64 and 1.4 mT, respectively). The spatial resolution of EPR images was enhanced by a factor of 2.3 using ammonium formate compared to lithium formate because its linewidth is about 0.75 mT narrower than that of lithium formate. The EPRI results were consistent to within 1% with those of Gafchromic EBT films and MC simulations at distances from 1.0 to 2.9 mm. The radial dose values obtained by EPRI were about 4% lower at distances from 2.9 to 4.0 mm than those determined by MC simulation and EBT film dosimetry. Conclusions: Ammonium formate is a suitable material under certain conditions for use in brachytherapy dosimetry using EPRI. In this study, the authors demonstrated that the EPRI technique allows the estimation of the relative radial dose distribution at short distances for a {sup 192}Ir wire source.

  1. 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.

  2. 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.

  3. Consideration of the electron energy distribution function shape in a Ar and N{sub 2} global model

    SciTech Connect (OSTI)

    Kang, Namjun; Oh, Soo-Ghee [Division of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of); Gaboriau, Freddy [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)

    2012-11-15T23:59:59.000Z

    This paper presents a method to compensate the effects of the electron energy distribution function (EEDF) shape on plasma characteristics when using global models to describe Ar and N{sub 2} inductively coupled discharges. A non-Maxwellian global model is developed for the pressure range 1-1000 mTorr by using an user-friendly Boltzmann equation solver to calculate the EEDF. The calculated EEDFs are compared with the measurements performed with a single Langmuir probe in the same conditions. We also compare the calculated results by using the Boltzmann equation solver with the results by assuming a Maxwellian EEDF and point out the influence of both methods on the contribution of the multi-step process on ionization. Finally, to take into account the shape of the EEDF in global models, abacuses are presented as a function of the absorbed power density and the pressure for typical Ar and N{sub 2} planar ICP discharges.

  4. The generalized parton distribution functions and the nucleon spin sum rules in the chiral quark soliton model

    E-Print Network [OSTI]

    M. Wakamatsu; H. Tsujimoto

    2005-03-29T23:59:59.000Z

    The theoretical predictions are given for the forward limit of the unpolarized spin-flip isovector generalized parton distribution function $(E^u - E^d)(x, \\xi, t)$ within the framework of the chiral quark soliton model, with full inclusion of the polarization of Dirac sea quarks. We observe that $[(H^u - H^d) + (E^u - E^d)](x,0,0)$ has a sharp peak around $x=0$, which we interpret as a signal of the importance of the pionic $q \\bar{q}$ excitation with large spatial extension in the transverse direction. Another interesting indication given by the predicted distribution in combination with Ji's angular momentum sum rule is that the $\\bar{d}$-quark carries more angular momentum than the $\\bar{u}$-quark in the proton, which may have some relation with the physics of the violation of the Gottfried sum rule.

  5. 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

  6. 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.

  7. Evaluating and developing parameter optimization and uncertainty analysis methods for a computationally intensive distributed hydrological model 

    E-Print Network [OSTI]

    Zhang, Xuesong

    2009-05-15T23:59:59.000Z

    ? weights for river stage prediction (Chau, 2006). Other evolutionary algorithms, such as Differential Evaluation (DE) (Storn and Price, 1997) and Artificial Immune Systems (AIS) (de Castro and Von Zuben, 2002a; de Castro and Von Zuben, 2002b), although... is to structure the hydrologic model as a probability model, then the confidence interval of model output can be computed (Montanari et al., 1997). Representative methods of this category include Markov Chain Monte Carlo (MCMC) and a Generalized Likelihood...

  8. Multiobjective calibration and sensitivity of a distributed land surface water and energy balance model

    E-Print Network [OSTI]

    Houser, Paul R; Gupta, Hoshin V; Shuttleworth, W. James; Famiglietti, James S

    2001-01-01T23:59:59.000Z

    identification and energy balance models on a tallgrassdata for surface energy balance evaluation of a semiaridWatershed. We are energy balance components over a semiarid

  9. Energy distribution and computer modeled nozzle design in high pressure water jet coating removal

    SciTech Connect (OSTI)

    Blades, B. [Hobart Tafa Technologies Inc., Concord, NH (United States)

    1994-12-31T23:59:59.000Z

    Wider acceptance of water jet coating removal as an industrial process has created a demand to better understand the physical phenomena occurring during coating removal. This demand stems from both technical and process control concerns. Research on behavior of coating removal nozzles and high pressure jets in general provide the basis for the development of a mathematical model of rotating nozzle. The model finds uses in both process development and new equipment design. Data confirming the validity of the model has been generated and the need for further refinement of the model has been noted.

  10. Improved Indoor Tracking Based on Generalized t-Distribution Noise Model

    E-Print Network [OSTI]

    Shuo, Liu; Le, Yin; Khuen, Ho Weng; Voon, Ling Keck

    2015-01-01T23:59:59.000Z

    log-distance path loss model (PLM) is commonly used [20]. Itclustered near the fitted PLM curve. B. Tracking of A Moving

  11. Dynamic Modeling of Aerobic Growth of Shewanella oneidensis. Predicting Triauxic Growth, Flux Distributions and Energy Requirement for Growth

    SciTech Connect (OSTI)

    Song, Hyun-Seob; Ramkrishna, Doraiswami; Pinchuk, Grigoriy E.; Beliaev, Alex S.; Konopka, Allan; Fredrickson, Jim K.

    2013-01-01T23:59:59.000Z

    A model-based analysis is conducted to investigate metabolism of Shewanella oneidensis MR-1 strain in aerobic batch culture, which exhibits an intriguing growth pattern by sequentially consuming substrate (i.e., lactate) and by-products (i.e., pyruvate and acetate). A general protocol is presented for developing a detailed network-based dynamic model for S. oneidensis based on the Lumped Hybrid Cybernetic Model (LHCM) framework. The L-HCM, although developed from only limited data, is shown to accurately reproduce exacting dynamic metabolic shifts, and provide reasonable estimates of energy requirement for growth. Flux distributions in S. oneidensis predicted by the L-HCM compare very favorably with 13C-metabolic flux analysis results reported in the literature. Predictive accuracy is enhanced by incorporating measurements of only a few intracellular fluxes, in addition to extracellular metabolites. The L-HCM developed here for S. oneidensis is consequently a promising tool for the analysis of intracellular flux distribution and metabolic engineering.

  12. OCCUPANCY DISTRIBUTIONS ARISING IN SAMPLING FROM GIBBS-POISSON ABUNDANCE MODELS

    E-Print Network [OSTI]

    together with a sampling model. We start with a discrete model of iid stochastic species abundances, each, which is a measure of richness or diversity of species. We rederive the sam- pling formulae1 , SERVET MART´INEZ2 (iid) stochastic species abundances d = 1, ..., n , based on Gibbs

  13. Behavioural insights into the Modelling of Freight Transportation and Distribution Systems

    E-Print Network [OSTI]

    Bertini, Robert L.

    fuelled the extension of supply chains and the globalization of the world economy. At the micro-step modelling paradigm cannot provide adequate answers in the twenty-first century global customer-driven economy. This special issue is dedicated to innovative modelling efforts that provide new insights

  14. Research Article A Network Modeling Approach for the Spatial Distribution and Structure

    E-Print Network [OSTI]

    Zhang, Aidong

    and diseased bone of 20­30 to 70­80 year-olds demonstrated the method's effectiveness for modeling osteoporosis data in clinical trials. KEY WORDS: bone; imaging; modeling; osteoporosis. INTRODUCTION According to the International Osteoporosis Foundation, osteoporosis is estimated to affect 200 million women and cause

  15. Ecological Modelling 105 (1997) 121 Interaction and spatial distribution of wetland nitrogen

    E-Print Network [OSTI]

    Florida, University of

    Elsevier Science B.V. Keywords: Wetland model; Nitrogen cycling; Wastewater treatment 1. Introduction methods of wetland treatment systems. This design ap- proach, referred to as `black box' methodology in wetlands, and (ii) factors affecting N removal from treatment wetlands. A mechanistic model was developed

  16. 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,

  17. 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-

  18. An aggregation model reduction method for one-dimensional distributed systems

    E-Print Network [OSTI]

    Skogestad, Sigurd

    example systems, namely a distillation column, a heat exchanger, and a fixed-bed reactor. Keywords Model, or continuous, like packed distillation columns, fixed-bed reactors, and heat exchangers. A special class

  19. An aggregation model reduction method for one-dimensional distributed parameter systems

    E-Print Network [OSTI]

    Skogestad, Sigurd

    column, a heat exchanger, and a fixed-bed reactor. Keywords Model reduction; Dynamic simulation distillation columns, fixed-bed reactors, and heat exchangers. A special class of discrete systems are spatial

  20. Heat Transfer Modeling and Use of Distributed Temperature Measurements to Predict Rate

    E-Print Network [OSTI]

    Hashmi, Gibran Mushtaq

    2014-07-08T23:59:59.000Z

    . .......................................... 53 Figure 21 – Rate simulation for the same case as Fig. 20. ............................................... 54 Figure 22 – Buildup charts for the same case as in Fig. 10. ............................................. 54 Figure 23 – Pareto chart... ................................................................................ 10 CHAPTER III MODEL DEVELOPMENT .................................................................... 12 Introduction .................................................................................................................. 12 Steady...

  1. Efficient Distributed Topic Modeling with Provable Guarantees Weicong Ding Mohammad H. Rohban Prakash Ishwar Venkatesh Saligrama

    E-Print Network [OSTI]

    Kaski, Samuel

    of size W among L servers. As is now common (Blei, 2012) we view each document as a collection of N i Dirichlet Allocation (LDA) (Blei et al., 2003) and Log-normal in Correlated Topic Model (Blei and Lafferty

  2. A Distributed Modeling System for Short-Term to Seasonal Ensemble Streamflow Forecasting in Snowmelt Dominated Basins

    SciTech Connect (OSTI)

    Wigmosta, Mark S.; Gill, Muhammad K.; Coleman, Andre M.; Prasad, Rajiv; Vail, Lance W.

    2007-12-01T23:59:59.000Z

    This paper describes a distributed modeling system for short-term to seasonal water supply forecasts with the ability to utilize remotely-sensed snow cover products and real-time streamflow measurements. Spatial variability in basin characteristics and meteorology is represented using a raster-based computational grid. Canopy interception, snow accumulation and melt, and simplified soil water movement are simulated in each computational unit. The model is run at a daily time step with surface runoff and subsurface flow aggregated at the basin scale. This approach allows the model to be updated with spatial snow cover and measured streamflow using an Ensemble Kalman-based data assimilation strategy that accounts for uncertainty in weather forecasts, model parameters, and observations used for updating. Model inflow forecasts for the Dworshak Reservoir in northern Idaho are compared to observations and to April-July volumetric forecasts issued by the Natural Resource Conservation Service (NRCS) for Water Years 2000 – 2006. October 1 volumetric forecasts are superior to those issued by the NRCS, while March 1 forecasts are comparable. The ensemble spread brackets the observed April-July volumetric inflows in all years. Short-term (one and three day) forecasts also show excellent agreement with observations.

  3. The multi-scattering model for calculations of positron spatial distribution in the multilayer stacks, useful for conventional positron measurements

    SciTech Connect (OSTI)

    Dryzek, Jerzy [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland) [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland); Institute of Physics, Opole University, ul. Oleska 48, 45-052 Opole (Poland); Siemek, Krzysztof [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland)] [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland)

    2013-08-21T23:59:59.000Z

    The spatial distribution of positrons emitted from radioactive isotopes into stacks or layered samples is a subject of the presented report. It was found that Monte Carlo (MC) simulations using GEANT4 code are not able to describe correctly the experimental data of the positron fractions in stacks. The mathematical model was proposed for calculations of the implantation profile or positron fractions in separated layers or foils being components of a stack. The model takes into account only two processes, i.e., the positron absorption and backscattering at interfaces. The mathematical formulas were applied in the computer program called LYS-1 (layers profile analysis). The theoretical predictions of the model were in the good agreement with the results of the MC simulations for the semi infinite sample. The experimental verifications of the model were performed on the symmetrical and non-symmetrical stacks of different foils. The good agreement between the experimental and calculated fractions of positrons in components of a stack was achieved. Also the experimental implantation profile obtained using the depth scanning of positron implantation technique is very well described by the theoretical profile obtained within the proposed model. The LYS-1 program allows us also to calculate the fraction of positrons which annihilate in the source, which can be useful in the positron spectroscopy.

  4. 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

  5. 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

  6. 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

  7. 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 ...

  8. MCNP modeling of the Swiss LWRs for the calculation of the in- and ex-vessel neutron flux distributions

    SciTech Connect (OSTI)

    Pantelias, M.; Volmert, B.; Caruso, S. [National Cooperative for the Disposal of Radioactive Waste Nagra, Hardstrasse 73, 5430, Wettingen (Switzerland); Zvoncek, P. [Laboratory for Nuclear Energy Systems, ETH Zurich, Sonneggstrasse 3, 8092, Zurich (Switzerland); Bitterli, B. [Kernkraftwerk Goesgen-Daeniken AG, 4658 Daeniken (Switzerland); Neukaeter, E.; Nissen, W. [BKW FMB Energie AG-Kernkraftwerk Muehleberg, 3203 Muehleberg (Switzerland); Ledergerber, G. [Kernkraftwerk Leibstadt AG, 5325 Leibstadt (Switzerland); Vielma, R. [Axpo AG-Kernkraftwerk Beznau, 5312 Doettingen (Switzerland)

    2012-07-01T23:59:59.000Z

    MCNP models of all Swiss Nuclear Power Plants have been developed by the National Cooperative for the Disposal of Radioactive Waste (Nagra), in collaboration with the utilities and ETH Zurich, for the 2011 decommissioning cost study. The estimation of the residual radionuclide inventories and corresponding activity levels of irradiated structures and components following the NPP shut-down is of crucial importance for the planning of the dismantling process, the waste packaging concept and, consequently, for the estimation of the decommissioning costs. Based on NPP specific data, the neutron transport simulations lead to the best yet knowledge of the neutron spectra necessary for the ensuing activation calculations. In this paper, the modeling concept towards the MCNP-NPPs is outlined and the resulting flux distribution maps are presented. (authors)

  9. 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

  10. 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 ...

  11. Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

    SciTech Connect (OSTI)

    Steward, D.; Penev, M.; Saur, G.; Becker, W.; Zuboy, J.

    2013-06-01T23:59:59.000Z

    This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity.

  12. A model of stress distribution in soft tissue under non-uniform loading

    E-Print Network [OSTI]

    Cunningham, Thomas Roy

    1981-01-01T23:59:59.000Z

    ='4a . 11. Minimum normal stress; h=Sa. o min -G min 70 sQ LIST OF FIGURES Figure Page Compression of the ear lobe under constant pressure of 100 mmHg Threshold curve for ulceration in hamstring muscle 3. Constant thickness tissue model 12... 4. Modified tissue model 14 5. Radial stress; thickness, Sa 22 6. Circumferential stress; thickness, 5a 7. Longitudinal stress; thickness, 5a 23 24 Shear stress; thickness, 5a 25 9. Minimum normal stress; thickness, Sa 10. Maximum normal...

  13. Parallel Bayesian MCMC Imputation for Multiple Distributed Lag Models: A Case Study in Environmental

    E-Print Network [OSTI]

    Jones, Galin

    data are frequently used to study the short-term effects of particulate matter air pollution allow to estimate the cumulative effect of air pollution exposure over few days in the past and therefore provide a more realistic measure of the health effects of air pollution than single lag models

  14. Evaluating CERES angular distribution models for snow using surface reflectance observations from the East Antarctic Plateau

    E-Print Network [OSTI]

    Warren, Stephen

    techniques. Data products produced by the CERES team include the observed broadband solar, window long- wave data processing algorithms, used to convert the observed upwelling radiance to an estimate of the upwelling hemispheric flux. We model top-of-atmosphere anisotropic reflectance factors using an atmospheric

  15. 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

  16. Introduction to Distributed Systems

    E-Print Network [OSTI]

    Pous, Damien

    1 Introduction to Distributed Systems Fabienne Boyer, LIG, fabienne.boyer@inria.fr Sources: Cours d'Olivier Gruber, Sacha Krakowiak, Sara Bouchenak, UJF Fabienne Boyer, Distributed Programming 2 Objectives Study conceptual and practical aspects of distributed systems l Client-server model l Distributed protocols l

  17. 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)

  18. 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

  19. Modern Grid Initiative Distribution Taxonomy Final Report

    SciTech Connect (OSTI)

    Schneider, Kevin P.; Chen, Yousu; Chassin, David P.; Pratt, Robert G.; Engel, David W.; Thompson, Sandra E.

    2008-11-01T23:59:59.000Z

    This is the final report for the development of a toxonomy of prototypical electrical distribution feeders. Two of the primary goals of the Department of Energy's (DOE) Modern Grid Initiative (MGI) are 'to accelerate the modernization of our nation's electricity grid' and to 'support demonstrations of systems of key technologies that can serve as the foundation for an integrated, modern power grid'. A key component to the realization of these goals is the effective implementation of new, as well as existing, 'smart grid technologies'. Possibly the largest barrier that has been identified in the deployment of smart grid technologies is the inability to evaluate how their deployment will affect the electricity infrastructure, both locally and on a regional scale. The inability to evaluate the impacts of these technologies is primarily due to the lack of detailed electrical distribution feeder information. While detailed distribution feeder information does reside with the various distribution utilities, there is no central repository of information that can be openly accessed. The role of Pacific Northwest National Laboratory (PNNL) in the MGI for FY08 was to collect distribution feeder models, in the SynerGEE{reg_sign} format, from electric utilities around the nation so that they could be analyzed to identify regional differences in feeder design and operation. Based on this analysis PNNL developed a taxonomy of 24 prototypical feeder models in the GridLAB-D simulations environment that contain the fundamental characteristics of non-urban core, radial distribution feeders from the various regions of the U.S. Weighting factors for these feeders are also presented so that they can be used to generate a representative sample for various regions within the United States. The final product presented in this report is a toolset that enables the evaluation of new smart grid technologies, with the ability to aggregate their effects to regional and national levels. The distribution feeder models presented in this report are based on actual utility models but do not contain any proprietary or system specific information. As a result, the models discussed in this report can be openly distributed to industry, academia, or any interested entity, in order to facilitate the ability to evaluate smart grid technologies.

  20. The Sixth International Conference on CSCW in Design. July 12-14, 2001, London, Ontario, Canada Modeling Workflow within Distributed Systems

    E-Print Network [OSTI]

    Yan, Yuhong

    Modeling Workflow within Distributed Systems Yuhong Yan, Alex Bejan* Flydragon Computer Consulting, NY, USA that modeling a workflow process in Standard Workflow Structures can guarantee the soundness of a workflow of a workflow management system is the support of the definition, execution, registration and control