National Library of Energy BETA

Sample records for time series models

  1. TIME SERIES MODELS OF THREE SETS OF RXTE OBSERVATIONS OF 4U 1543-47

    SciTech Connect (OSTI)

    Koen, C.

    2013-03-01

    The X-ray nova 4U 1543-47 was in a different physical state (low/hard, high/soft, and very high) during the acquisition of each of the three time series analyzed in this paper. Standard time series models of the autoregressive moving average (ARMA) family are fitted to these series. The low/hard data can be adequately modeled by a simple low-order model with fixed coefficients, once the slowly varying mean count rate has been accounted for. The high/soft series requires a higher order model, or an ARMA model with variable coefficients. The very high state is characterized by a succession of 'dips', with roughly equal depths. These seem to appear independently of one another. The underlying stochastic series can again be modeled by an ARMA form, or roughly as the sum of an ARMA series and white noise. The structuring of each model in terms of short-lived aperiodic and 'quasi-periodic' components is discussed.

  2. Time Series Database

    Energy Science and Technology Software Center (OSTI)

    2007-11-02

    TSDB is a Python module for storing large volumes of time series data. TSDB stores data in binary files indexed by a timestamp. Aggregation functions (such as rate, sum, avg, etc.) can be performed on the data, but data is never discarded. TSDB is presently best suited for SNMP data but new data types are easily added.

  3. Data Tools & Models - Time Series - U.S. Energy Information Administration

    Gasoline and Diesel Fuel Update (EIA)

    (EIA) The following is a list of EIA's principle data series that span time. Alternative Fuels Alternative transportation fuels (atf) and alternative fueled vehicles (AFV) Historical data on alternative fueled vehicles in use and alternate transportation fuel consumption. Data on the following items: 1) the number of alternative fueled vehicles (AFVs) supplied each year; i.e., new AFVs and conventionally fueled vehicles converted to operate on an alternate fuel; 2) for a limited set of fleet

  4. Statistical criteria for characterizing irradiance time series.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

    2010-10-01

    We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

  5. A Bayesian method for characterizing distributed micro-releases: II. inference under model uncertainty with short time-series data.

    SciTech Connect (OSTI)

    Marzouk, Youssef; Fast P. (Lawrence Livermore National Laboratory, Livermore, CA); Kraus, M.; Ray, J. P.

    2006-01-01

    Terrorist attacks using an aerosolized pathogen preparation have gained credibility as a national security concern after the anthrax attacks of 2001. The ability to characterize such attacks, i.e., to estimate the number of people infected, the time of infection, and the average dose received, is important when planning a medical response. We address this question of characterization by formulating a Bayesian inverse problem predicated on a short time-series of diagnosed patients exhibiting symptoms. To be of relevance to response planning, we limit ourselves to 3-5 days of data. In tests performed with anthrax as the pathogen, we find that these data are usually sufficient, especially if the model of the outbreak used in the inverse problem is an accurate one. In some cases the scarcity of data may initially support outbreak characterizations at odds with the true one, but with sufficient data the correct inferences are recovered; in other words, the inverse problem posed and its solution methodology are consistent. We also explore the effect of model error-situations for which the model used in the inverse problem is only a partially accurate representation of the outbreak; here, the model predictions and the observations differ by more than a random noise. We find that while there is a consistent discrepancy between the inferred and the true characterizations, they are also close enough to be of relevance when planning a response.

  6. Integrated method for chaotic time series analysis

    DOE Patents [OSTI]

    Hively, L.M.; Ng, E.G.

    1998-09-29

    Methods and apparatus for automatically detecting differences between similar but different states in a nonlinear process monitor nonlinear data are disclosed. Steps include: acquiring the data; digitizing the data; obtaining nonlinear measures of the data via chaotic time series analysis; obtaining time serial trends in the nonlinear measures; and determining by comparison whether differences between similar but different states are indicated. 8 figs.

  7. Integrated method for chaotic time series analysis

    DOE Patents [OSTI]

    Hively, Lee M.; Ng, Esmond G.

    1998-01-01

    Methods and apparatus for automatically detecting differences between similar but different states in a nonlinear process monitor nonlinear data. Steps include: acquiring the data; digitizing the data; obtaining nonlinear measures of the data via chaotic time series analysis; obtaining time serial trends in the nonlinear measures; and determining by comparison whether differences between similar but different states are indicated.

  8. A combined method to estimate parameters of the thalamocortical model from a heavily noise-corrupted time series of action potential

    SciTech Connect (OSTI)

    Wang, Ruofan; Wang, Jiang; Deng, Bin Liu, Chen; Wei, Xile; Tsang, K. M.; Chan, W. L.

    2014-03-15

    A combined method composing of the unscented Kalman filter (UKF) and the synchronization-based method is proposed for estimating electrophysiological variables and parameters of a thalamocortical (TC) neuron model, which is commonly used for studying Parkinson's disease for its relay role of connecting the basal ganglia and the cortex. In this work, we take into account the condition when only the time series of action potential with heavy noise are available. Numerical results demonstrate that not only this method can estimate model parameters from the extracted time series of action potential successfully but also the effect of its estimation is much better than the only use of the UKF or synchronization-based method, with a higher accuracy and a better robustness against noise, especially under the severe noise conditions. Considering the rather important role of TC neuron in the normal and pathological brain functions, the exploration of the method to estimate the critical parameters could have important implications for the study of its nonlinear dynamics and further treatment of Parkinson's disease.

  9. STUDIES IN ASTRONOMICAL TIME SERIES ANALYSIS. VI. BAYESIAN BLOCK REPRESENTATIONS

    SciTech Connect (OSTI)

    Scargle, Jeffrey D.; Norris, Jay P.; Jackson, Brad; Chiang, James

    2013-02-20

    This paper addresses the problem of detecting and characterizing local variability in time series and other forms of sequential data. The goal is to identify and characterize statistically significant variations, at the same time suppressing the inevitable corrupting observational errors. We present a simple nonparametric modeling technique and an algorithm implementing it-an improved and generalized version of Bayesian Blocks-that finds the optimal segmentation of the data in the observation interval. The structure of the algorithm allows it to be used in either a real-time trigger mode, or a retrospective mode. Maximum likelihood or marginal posterior functions to measure model fitness are presented for events, binned counts, and measurements at arbitrary times with known error distributions. Problems addressed include those connected with data gaps, variable exposure, extension to piecewise linear and piecewise exponential representations, multivariate time series data, analysis of variance, data on the circle, other data modes, and dispersed data. Simulations provide evidence that the detection efficiency for weak signals is close to a theoretical asymptotic limit derived by Arias-Castro et al. In the spirit of Reproducible Research all of the code and data necessary to reproduce all of the figures in this paper are included as supplementary material.

  10. Multifractal analysis of time series generated by discrete Ito equations

    SciTech Connect (OSTI)

    Telesca, Luciano; Czechowski, Zbigniew; Lovallo, Michele

    2015-06-15

    In this study, we show that discrete Ito equations with short-tail Gaussian marginal distribution function generate multifractal time series. The multifractality is due to the nonlinear correlations, which are hidden in Markov processes and are generated by the interrelation between the drift and the multiplicative stochastic forces in the Ito equation. A link between the range of the generalized Hurst exponents and the mean of the squares of all averaged net forces is suggested.

  11. Chaotic time series analysis in economics: Balance and perspectives

    SciTech Connect (OSTI)

    Faggini, Marisa

    2014-12-15

    The aim of the paper is not to review the large body of work concerning nonlinear time series analysis in economics, about which much has been written, but rather to focus on the new techniques developed to detect chaotic behaviours in economic data. More specifically, our attention will be devoted to reviewing some of these techniques and their application to economic and financial data in order to understand why chaos theory, after a period of growing interest, appears now not to be such an interesting and promising research area.

  12. Integrated Mathematical Modeling Software Series of Vehicle Propulsion...

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

    Mathematical Modeling Software Series of Vehicle Propulsion System: (1) Tractive Effort (T sub ew) of Vehicle Road WheelTrack Sprocket Integrated Mathematical Modeling Software ...

  13. Time series power flow analysis for distribution connected PV generation.

    SciTech Connect (OSTI)

    Broderick, Robert Joseph; Quiroz, Jimmy Edward; Ellis, Abraham; Reno, Matthew J.; Smith, Jeff; Dugan, Roger

    2013-01-01

    Distributed photovoltaic (PV) projects must go through an interconnection study process before connecting to the distribution grid. These studies are intended to identify the likely impacts and mitigation alternatives. In the majority of the cases, system impacts can be ruled out or mitigation can be identified without an involved study, through a screening process or a simple supplemental review study. For some proposed projects, expensive and time-consuming interconnection studies are required. The challenges to performing the studies are twofold. First, every study scenario is potentially unique, as the studies are often highly specific to the amount of PV generation capacity that varies greatly from feeder to feeder and is often unevenly distributed along the same feeder. This can cause location-specific impacts and mitigations. The second challenge is the inherent variability in PV power output which can interact with feeder operation in complex ways, by affecting the operation of voltage regulation and protection devices. The typical simulation tools and methods in use today for distribution system planning are often not adequate to accurately assess these potential impacts. This report demonstrates how quasi-static time series (QSTS) simulation and high time-resolution data can be used to assess the potential impacts in a more comprehensive manner. The QSTS simulations are applied to a set of sample feeders with high PV deployment to illustrate the usefulness of the approach. The report describes methods that can help determine how PV affects distribution system operations. The simulation results are focused on enhancing the understanding of the underlying technical issues. The examples also highlight the steps needed to perform QSTS simulation and describe the data needed to drive the simulations. The goal of this report is to make the methodology of time series power flow analysis readily accessible to utilities and others responsible for evaluating

  14. Characterizing system dynamics with a weighted and directed network constructed from time series data

    SciTech Connect (OSTI)

    Sun, Xiaoran; School of Mathematics and Statistics, The University of Western Australia, Crawley WA 6009 ; Small, Michael; Zhao, Yi; Xue, Xiaoping

    2014-06-15

    In this work, we propose a novel method to transform a time series into a weighted and directed network. For a given time series, we first generate a set of segments via a sliding window, and then use a doubly symbolic scheme to characterize every windowed segment by combining absolute amplitude information with an ordinal pattern characterization. Based on this construction, a network can be directly constructed from the given time series: segments corresponding to different symbol-pairs are mapped to network nodes and the temporal succession between nodes is represented by directed links. With this conversion, dynamics underlying the time series has been encoded into the network structure. We illustrate the potential of our networks with a well-studied dynamical model as a benchmark example. Results show that network measures for characterizing global properties can detect the dynamical transitions in the underlying system. Moreover, we employ a random walk algorithm to sample loops in our networks, and find that time series with different dynamics exhibits distinct cycle structure. That is, the relative prevalence of loops with different lengths can be used to identify the underlying dynamics.

  15. Identification of periods of clear sky irradiance in time series of GHI measurements

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

    Reno, Matthew J.; Hansen, Clifford W.

    2016-01-18

    In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

  16. Wavelet-based surrogate time series for multiscale simulation of heterogeneous catalysis

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

    Savara, Aditya Ashi; Daw, C. Stuart; Xiong, Qingang; Gur, Sourav; Danielson, Thomas L.; Hin, Celine N.; Pannala, Sreekanth; Frantziskonis, George N.

    2016-01-28

    We propose a wavelet-based scheme that encodes the essential dynamics of discrete microscale surface reactions in a form that can be coupled with continuum macroscale flow simulations with high computational efficiency. This makes it possible to simulate the dynamic behavior of reactor-scale heterogeneous catalysis without requiring detailed concurrent simulations at both the surface and continuum scales using different models. Our scheme is based on the application of wavelet-based surrogate time series that encodes the essential temporal and/or spatial fine-scale dynamics at the catalyst surface. The encoded dynamics are then used to generate statistically equivalent, randomized surrogate time series, which canmore » be linked to the continuum scale simulation. As a result, we illustrate an application of this approach using two different kinetic Monte Carlo simulations with different characteristic behaviors typical for heterogeneous chemical reactions.« less

  17. Integrated Mathematical Modeling Software Series of Vehicle Propulsion

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

    System: (1) Tractive Effort (T sub ew) of Vehicle Road Wheel/Track Sprocket | Department of Energy Mathematical Modeling Software Series of Vehicle Propulsion System: (1) Tractive Effort (T sub ew) of Vehicle Road Wheel/Track Sprocket Integrated Mathematical Modeling Software Series of Vehicle Propulsion System: (1) Tractive Effort (T sub ew) of Vehicle Road Wheel/Track Sprocket Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit,

  18. Use of Long Time-series ACRF Measurements to Improve Data Quality...

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

    1 Use of Long Time-Series ACRF Measurements to Improve Data Quality Analysis Sean Moore Mission Research and Technical Services Santa Barbara, CA ARM Data Quality Office...

  19. Possible bias in tree-ring time series due to mortality (Journal...

    Office of Scientific and Technical Information (OSTI)

    Subject: 54 ENVIRONMENTAL SCIENCES; 63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; TREE RINGS; TIME-SERIES ANALYSIS; AIR POLLUTION; ...

  20. Generalized Optoelectronic Model of Series-Connected Multijunction Solar Cells

    SciTech Connect (OSTI)

    Geisz, John F.; Steiner, Myles A.; Garcia, Ivan; France, Ryan M.; McMahon, William E.; Osterwald, Carl R.; Friedman, Daniel J.

    2015-11-01

    The emission of light from each junction in a series-connected multijunction solar cell, we found, both complicates and elucidates the understanding of its performance under arbitrary conditions. Bringing together many recent advances in this understanding, we present a general 1-D model to describe luminescent coupling that arises from both voltage-driven electroluminescence and voltage-independent photoluminescence in nonideal junctions that include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger recombination, shunt resistance, reverse-bias breakdown, series resistance, and significant dark area losses. The individual junction voltages and currents are experimentally determined from measured optical and electrical inputs and outputs of the device within the context of the model to fit parameters that describe the devices performance under arbitrary input conditions. Furthermore, our techniques to experimentally fit the model are demonstrated for a four-junction inverted metamorphic solar cell, and the predictions of the model are compared with concentrator flash measurements.

  1. Generalized Optoelectronic Model of Series-Connected Multijunction Solar Cells

    SciTech Connect (OSTI)

    Geisz, John F.; Steiner, Myles A.; Garcia, Ivan; France, Ryan M.; McMahon, William E.; Osterwald, Carl R.; Friedman, Daniel J.

    2015-10-02

    The emission of light from each junction in a series-connected multijunction solar cell, we found, both complicates and elucidates the understanding of its performance under arbitrary conditions. Bringing together many recent advances in this understanding, we present a general 1-D model to describe luminescent coupling that arises from both voltage-driven electroluminescence and voltage-independent photoluminescence in nonideal junctions that include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger recombination, shunt resistance, reverse-bias breakdown, series resistance, and significant dark area losses. The individual junction voltages and currents are experimentally determined from measured optical and electrical inputs and outputs of the device within the context of the model to fit parameters that describe the devices performance under arbitrary input conditions. Furthermore, our techniques to experimentally fit the model are demonstrated for a four-junction inverted metamorphic solar cell, and the predictions of the model are compared with concentrator flash measurements.

  2. Genome-wide Selective Sweeps in Natural Bacterial Populations Revealed by Time-series Metagenomics

    SciTech Connect (OSTI)

    Chan, Leong-Keat; Bendall, Matthew L.; Malfatti, Stephanie; Schwientek, Patrick; Tremblay, Julien; Schackwitz, Wendy; Martin, Joel; Pati, Amrita; Bushnell, Brian; Foster, Brian; Kang, Dongwan; Tringe, Susannah G.; Bertilsson, Stefan; Moran, Mary Ann; Shade, Ashley; Newton, Ryan J.; Stevens, Sarah; McMcahon, Katherine D.; Mamlstrom, Rex R.

    2014-05-12

    Multiple evolutionary models have been proposed to explain the formation of genetically and ecologically distinct bacterial groups. Time-series metagenomics enables direct observation of evolutionary processes in natural populations, and if applied over a sufficiently long time frame, this approach could capture events such as gene-specific or genome-wide selective sweeps. Direct observations of either process could help resolve how distinct groups form in natural microbial assemblages. Here, from a three-year metagenomic study of a freshwater lake, we explore changes in single nucleotide polymorphism (SNP) frequencies and patterns of gene gain and loss in populations of Chlorobiaceae and Methylophilaceae. SNP analyses revealed substantial genetic heterogeneity within these populations, although the degree of heterogeneity varied considerably among closely related, co-occurring Methylophilaceae populations. SNP allele frequencies, as well as the relative abundance of certain genes, changed dramatically over time in each population. Interestingly, SNP diversity was purged at nearly every genome position in one of the Chlorobiaceae populations over the course of three years, while at the same time multiple genes either swept through or were swept from this population. These patterns were consistent with a genome-wide selective sweep, a process predicted by the ecotype model? of diversification, but not previously observed in natural populations.

  3. Real-time Series Resistance Monitoring in PV Systems; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    Deceglie, M. G.; Silverman, T. J.; Marion, B.; Kurtz, S. R.

    2015-06-14

    We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.

  4. The application of complex network time series analysis in turbulent heated jets

    SciTech Connect (OSTI)

    Charakopoulos, A. K.; Karakasidis, T. E. Liakopoulos, A.; Papanicolaou, P. N.

    2014-06-15

    In the present study, we applied the methodology of the complex network-based time series analysis to experimental temperature time series from a vertical turbulent heated jet. More specifically, we approach the hydrodynamic problem of discriminating time series corresponding to various regions relative to the jet axis, i.e., time series corresponding to regions that are close to the jet axis from time series originating at regions with a different dynamical regime based on the constructed network properties. Applying the transformation phase space method (k nearest neighbors) and also the visibility algorithm, we transformed time series into networks and evaluated the topological properties of the networks such as degree distribution, average path length, diameter, modularity, and clustering coefficient. The results show that the complex network approach allows distinguishing, identifying, and exploring in detail various dynamical regions of the jet flow, and associate it to the corresponding physical behavior. In addition, in order to reject the hypothesis that the studied networks originate from a stochastic process, we generated random network and we compared their statistical properties with that originating from the experimental data. As far as the efficiency of the two methods for network construction is concerned, we conclude that both methodologies lead to network properties that present almost the same qualitative behavior and allow us to reveal the underlying system dynamics.

  5. Precursory signatures of protein folding/unfolding: From time series correlation analysis to atomistic mechanisms

    SciTech Connect (OSTI)

    Hsu, P. J.; Lai, S. K., E-mail: sklai@coll.phy.ncu.edu.tw [Complex Liquids Laboratory, Department of Physics, National Central University, Chungli 320 Taiwan (China); Molecular Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan (China); Cheong, S. A. [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

    2014-05-28

    Folded conformations of proteins in thermodynamically stable states have long lifetimes. Before it folds into a stable conformation, or after unfolding from a stable conformation, the protein will generally stray from one random conformation to another leading thus to rapid fluctuations. Brief structural changes therefore occur before folding and unfolding events. These short-lived movements are easily overlooked in studies of folding/unfolding for they represent momentary excursions of the protein to explore conformations in the neighborhood of the stable conformation. The present study looks for precursory signatures of protein folding/unfolding within these rapid fluctuations through a combination of three techniques: (1) ultrafast shape recognition, (2) time series segmentation, and (3) time series correlation analysis. The first procedure measures the differences between statistical distance distributions of atoms in different conformations by calculating shape similarity indices from molecular dynamics simulation trajectories. The second procedure is used to discover the times at which the protein makes transitions from one conformation to another. Finally, we employ the third technique to exploit spatial fingerprints of the stable conformations; this procedure is to map out the sequences of changes preceding the actual folding and unfolding events, since strongly correlated atoms in different conformations are different due to bond and steric constraints. The aforementioned high-frequency fluctuations are therefore characterized by distinct correlational and structural changes that are associated with rate-limiting precursors that translate into brief segments. Guided by these technical procedures, we choose a model system, a fragment of the protein transthyretin, for identifying in this system not only the precursory signatures of transitions associated with ? helix and ? hairpin, but also the important role played by weaker correlations in such protein

  6. Spatial time-series: Pollution pattern recognition under irregular interventions. Master`s thesis

    SciTech Connect (OSTI)

    Wright, S.A.

    1995-03-01

    The Fernald Environmental Restoration Management Corporation (FERMCO) has noted the introduction of arsenic contamination to groundwater around the area of the groundwater recovery system, which captures uranium contaminated groundwater. The introduction of arsenic occurs during high levels of pumping and is particularly sensitive to the western two of the five pumps. Auto-Regressive Moving Average (ARMA) and Spatial-Temporal ARMA (STARMA) empirical analyses are used to model the level of arsenic contamination found through time. The intervention of varied levels of pumping is modeled with a transfer function using analytic techniques to create a causal intervention transfer function input series to give physical meaning to the impulse response weights found. Spatial weights employed in the STARMA modeling are also created using analytic, causal methods. Results suggest a physical interpretation of the relationship between a particular level of pumping and the amount of arsenic to be found at the site in the temporal case, while including the effect of the pumping on a site of interest`s neighbors in the spatial-temporal case. Models presented may be employed in the forecasting of arsenic levels at monitoring well sites due to a given change in the operation level of the groundwater recovery system.

  7. Generalized Optoelectronic Model of Series-Connected Multijunction Solar Cells

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

    Geisz, John F.; Steiner, Myles A.; Garcia, Ivan; France, Ryan M.; McMahon, William E.; Osterwald, Carl R.; Friedman, Daniel J.

    2015-10-02

    The emission of light from each junction in a series-connected multijunction solar cell, we found, both complicates and elucidates the understanding of its performance under arbitrary conditions. Bringing together many recent advances in this understanding, we present a general 1-D model to describe luminescent coupling that arises from both voltage-driven electroluminescence and voltage-independent photoluminescence in nonideal junctions that include effects such as Sah-Noyce-Shockley (SNS) recombination with n ≠ 2, Auger recombination, shunt resistance, reverse-bias breakdown, series resistance, and significant dark area losses. The individual junction voltages and currents are experimentally determined from measured optical and electrical inputs and outputs ofmore » the device within the context of the model to fit parameters that describe the devices performance under arbitrary input conditions. Furthermore, our techniques to experimentally fit the model are demonstrated for a four-junction inverted metamorphic solar cell, and the predictions of the model are compared with concentrator flash measurements.« less

  8. Climate signal detection using wavelet transform: How to make a time series sing

    SciTech Connect (OSTI)

    Lau, K.M.; Weng, H.

    1995-12-01

    In this paper, the application of the wavelet transform (WT) to climate time series analyses is introduced. A tutorial description of the basic concept of WT, compared with similar concepts used in music, is also provided. Using an analogy between WT representation of a time series and a music score, the authors illustrate the importance of local versus global information in the time-frequency localization of climate signals. Examples of WT applied to climate data analysis are demonstrated using analytic signals as well as real climate time series. Results of WT applied to two climate time series-that is, a proxy paleoclimate time series with a 2.5-Myr deep-sea sediment record of {gamma}{sup 18}O and a 140-yr monthly record of Northern Hemisphere surface temperature-are presented. The former shows the presence of a 40-kyr and a 100-kyr oscillation and an abrupt transition in the oscillation regime at 0.7 Myr before the present, consistent with previous studies. The latter possesses a myriad of oscillatory modes f rom interannual (2-5 yr), interdecadal (10-12 yr, 20-25 yr, and 40-60 yr), and century ({approximately}180 yr) scales at different periods of the data record. In spite of the large difference in timescales, common features in time-frequency characteristics of these two time series have been identified. These features suggest that the variations of the earth`s climate are consistent with those exhibited by a nonlinear dynamical system under external forcings. 32 refs., 9 figs.

  9. Time Series Evaluation of Radiation Portal Monitor Data for Point Source Detection

    SciTech Connect (OSTI)

    Robinson, Sean M.; Bender, Sarah E.; Flumerfelt, Eric L.; Lopresti, Charles A.; Woodring, Mitchell L.

    2009-12-08

    The time series of data from a Radiation Portal Monitor (RPM) system are evaluated for the presence of point sources by isolating the contribution of anomalous radiation. Energy-windowed background spectra taken from the RPM are compared with the observed spectra at each time step during a vehicle drive-through. The total signal is turned into a spectral distance index using this method. This provides a time series with reduced systematic fluctuations due to background attenuation by the vehicle, and allows for point source detection by time-series analyses. The anomalous time series is reanalyzed by using a wavelet filter function of similar size to the expected source profile. A number of real drive-through data sets taken at a U.S. port of entry are analyzed in this way. A set of isotopes are injected into the data set, and the resultant benign and injected data sets are analyzed with gross-counting, spectral-ratio, and time-based algorithms. Spectral and time methods together offer a significant increase to detection performance.

  10. Dynamic driving cycle analyses using electric vehicle time-series data

    SciTech Connect (OSTI)

    Staackmann, M.; Liaw, B.Y.; Yun, D.Y.Y.

    1997-12-31

    Dynamic analyses of time-series data collected from real-world driving-cycle field testing of electric vehicles is providing evidence that certain driving-cycle conditions can significantly impact vehicle performance. In addition, vehicle performance results derived from time-series data show relationships that help to characterize driving cycles. Such findings confirm the advantages of time-series data over statistical data, in allowing correlation of vehicle performance characteristics with driving cycles. The driving-cycle vehicle performance analyses were performed using time-series data collected at the Electric and Hybrid Vehicle (EHV) National Data Center (NDC). A total of 71 EHVs are registered in the NDC and over 4,000 trips files have already been uploaded into the NDC database, as of may 1997. Numerous EHVs on multiple trips have been analyzed over the past two years. This paper presents the results of time-series data collected and analyzed for two specific vehicles of the overall program, to illustrate the value of time-series data. The data were analyzed to establish criteria for defining different driving cycles for the day-to-day trips made by vehicles in the program. The authors examined specific parameters such as average vehicle speed, number of stops during a trip, average distance traveled between stops, vehicle acceleration, and average DC kWh consumed per kilometer. Correlation among various parameters is presented in relationship to three driving cycles (highway, suburban, and urban), along with suggested ranges of parametric values defining the regimes of the different cycles.

  11. Parametric time series analysis of cold and hot spells in daily temperature: An application in Southern Italy

    SciTech Connect (OSTI)

    Macchiato, M. ); Serio, C. ); Lapenna, V. ); Rotonda, L.La. )

    1993-07-01

    The statistical analysis of cold air temperatures (cold spells) and hot air temperatures (hot spells) is discussed. Air temperature time series observed at 50 stations in southern Italy are investigated. The deterministic and stochastic components of the time series are identified and described by a dynamic-stochastic model that is periodic in the deterministic part (the annual cycle) and Markovian (first-order autoregressive) in the stochastic part. The annual cycle is described by only a few Fourier coefficients. Based on the model fitted to the data, the theoretical probability of cold (hot) spells is computed and compared to that estimated from the observed data. Spatial patterns of identified that make it possible to extrapolate the probability of cold (hot) spells at locations where no direct observations are available. 19 refs., 13 figs., 2 tabs.

  12. Convergence of statistical moments of particle density time series in scrape-off layer plasmas

    SciTech Connect (OSTI)

    Kube, R. Garcia, O. E.

    2015-01-15

    Particle density fluctuations in the scrape-off layer of magnetically confined plasmas, as measured by gas-puff imaging or Langmuir probes, are modeled as the realization of a stochastic process in which a superposition of pulses with a fixed shape, an exponential distribution of waiting times, and amplitudes represents the radial motion of blob-like structures. With an analytic formulation of the process at hand, we derive expressions for the mean squared error on estimators of sample mean and sample variance as a function of sample length, sampling frequency, and the parameters of the stochastic process. Employing that the probability distribution function of a particularly relevant stochastic process is given by the gamma distribution, we derive estimators for sample skewness and kurtosis and expressions for the mean squared error on these estimators. Numerically, generated synthetic time series are used to verify the proposed estimators, the sample length dependency of their mean squared errors, and their performance. We find that estimators for sample skewness and kurtosis based on the gamma distribution are more precise and more accurate than common estimators based on the method of moments.

  13. Measurements of time average series resonance effect in capacitively coupled radio frequency discharge plasma

    SciTech Connect (OSTI)

    Bora, B.; Bhuyan, H.; Favre, M.; Wyndham, E.; Chuaqui, H.; Kakati, M.

    2011-10-15

    Self-excited plasma series resonance is observed in low pressure capacitvely coupled radio frequency discharges as high-frequency oscillations superimposed on the normal radio frequency current. This high-frequency contribution to the radio frequency current is generated by a series resonance between the capacitive sheath and the inductive and resistive bulk plasma. In this report, we present an experimental method to measure the plasma series resonance in a capacitively coupled radio frequency argon plasma by modifying the homogeneous discharge model. The homogeneous discharge model is modified by introducing a correction factor to the plasma resistance. Plasma parameters are also calculated by considering the plasma series resonances effect. Experimental measurements show that the self-excitation of the plasma series resonance, which arises in capacitive discharge due to the nonlinear interaction of plasma bulk and sheath, significantly enhances both the Ohmic and stochastic heating. The experimentally measured total dissipation, which is the sum of the Ohmic and stochastic heating, is found to increase significantly with decreasing pressure.

  14. Transportation Energy Futures Series: Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints

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

    LIGHT-DUTY VEHICLES Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints TRANSPORTATION ENERGY FUTURES SERIES: Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints A Study Sponsored by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy March 2013 Prepared by ARGONNE NATIONAL LABORATORY Argonne, IL 60439 managed by U Chicago Argonne, LLC for the U.S. DEPARTMENT OF ENERGY under contract

  15. Identification of mixing effects in stratified chilled-water storage tanks by analysis of time series temperature data

    SciTech Connect (OSTI)

    Caldwell, J.S.; Bahnfleth, W.P.

    1998-12-31

    Several one-dimensional models of mixing in stratified chilled-water thermal energy storage tanks have been proposed. In the simplest models, mixing is assumed to be uniform throughout the tank. Other models permit spatial variation of mixing intensity. Published models were developed by adjusting model parameters to achieve qualitative agreement with measured profiles. The literature does not describe quantitative criteria for evaluating the performance of mixing models. This paper describes a method that can be used to determine the relative spatial distribution of mixing effects directly from experimental data. It also illustrates a method for quantitative comparison of experimental and modeled temperature profiles. The mixing calculation procedure may be applied to instantaneous spatial temperature data if temperature sensor spacing is sufficiently small. When sensors are widely spaced, time series data taken at individual sensors provide better accuracy. A criterion for maximum sensor spacing is proposed. The application of these procedures to time series charge-cycle operating data from a full-scale chilled-water thermal storage system serving a large medical center is described. Results of this analysis indicate that mixing is localized near the inlet diffuser and that one-dimensional flow with streamwise conduction predominates in most of the tank.

  16. Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

    SciTech Connect (OSTI)

    Martin, Luis; Marchante, Ruth; Cony, Marco; Zarzalejo, Luis F.; Polo, Jesus; Navarro, Ana

    2010-10-15

    Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as the temporal capacity of the back-up system. These plants can work like a conventional power plant and compete in the energy stock market avoiding intermittence in electricity production. This work presents a comparisons of statistical models based on time series applied to predict half daily values of global solar irradiance with a temporal horizon of 3 days. Half daily values consist of accumulated hourly global solar irradiance from solar raise to solar noon and from noon until dawn for each day. The dataset of ground solar radiation used belongs to stations of Spanish National Weather Service (AEMet). The models tested are autoregressive, neural networks and fuzzy logic models. Due to the fact that half daily solar irradiance time series is non-stationary, it has been necessary to transform it to two new stationary variables (clearness index and lost component) which are used as input of the predictive models. Improvement in terms of RMSD of the models essayed is compared against the model based on persistence. The validation process shows that all models essayed improve persistence. The best approach to forecast half daily values of solar irradiance is neural network models with lost component as input, except Lerida station where models based on clearness index have less uncertainty because this magnitude has a linear behaviour and it is easier to simulate by models. (author)

  17. Time Series Evaluation of Radiation Portal Monitor Data for Point Source Discrimination.

    SciTech Connect (OSTI)

    Robinson, Sean M.; Bender, Sarah E.; Flumerfelt, Eric L.; Lopresti, Charles A.; Woodring, Mitchell L.

    2009-07-20

    A novel algorithm approach to evaluating data from PVT-based Radiation Portal Monitor (RPM) systems is established. Time series of data from RPMs are evaluated for the presence of sources of interest by comparing the background to the vehicle spectrum at each successive time step, isolating the contribution of anomalous radiation. At each time in the data sequence, a spectral distance index is calculated using this method. This method may dramatically reduce systematic fluctuations due to background attenuation by a vehicle (the so-called shadow shielding effect), and allow for time-series matched filtering for discrimination of compact anomalous sources. This is attempted by using a wavelet filter function of similar size to the expected source profile on the output of the spectral distance method. Performance of this method is shown by analysis (injection studies) of a number of real drive-through data sets taken at a U.S. port of entry. Spectra from isotopes of interest are injected into the data set, and the resultant benign and injected data sets are analyzed with gross-counting, spectral distance, and spatial algorithms. The combination of spectral and spatial analysis methods showed a significant increase to detection performance.

  18. Transportation Energy Futures Series. Vehicle Technology Deployment Pathways. An Examination of Timing and Investment Constraints

    SciTech Connect (OSTI)

    Plotkin, Steve; Stephens, Thomas; McManus, Walter

    2013-03-01

    Scenarios of new vehicle technology deployment serve various purposes; some will seek to establish plausibility. This report proposes two reality checks for scenarios: (1) implications of manufacturing constraints on timing of vehicle deployment and (2) investment decisions required to bring new vehicle technologies to market. An estimated timeline of 12 to more than 22 years from initial market introduction to saturation is supported by historical examples and based on the product development process. Researchers also consider the series of investment decisions to develop and build the vehicles and their associated fueling infrastructure. A proposed decision tree analysis structure could be used to systematically examine investors' decisions and the potential outcomes, including consideration of cash flow and return on investment. This method requires data or assumptions about capital cost, variable cost, revenue, timing, and probability of success/failure, and would result in a detailed consideration of the value proposition of large investments and long lead times. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  19. Transportation Energy Futures Series: Vehicle Technology Deployment Pathways: An Examination of Timing and Investment Constraints

    SciTech Connect (OSTI)

    Plotkin, S.; Stephens, T.; McManus, W.

    2013-03-01

    Scenarios of new vehicle technology deployment serve various purposes; some will seek to establish plausibility. This report proposes two reality checks for scenarios: (1) implications of manufacturing constraints on timing of vehicle deployment and (2) investment decisions required to bring new vehicle technologies to market. An estimated timeline of 12 to more than 22 years from initial market introduction to saturation is supported by historical examples and based on the product development process. Researchers also consider the series of investment decisions to develop and build the vehicles and their associated fueling infrastructure. A proposed decision tree analysis structure could be used to systematically examine investors' decisions and the potential outcomes, including consideration of cash flow and return on investment. This method requires data or assumptions about capital cost, variable cost, revenue, timing, and probability of success/failure, and would result in a detailed consideration of the value proposition of large investments and long lead times. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  20. Interpretation of engine cycle-to-cycle variation by chaotic time series analysis

    SciTech Connect (OSTI)

    Daw, C.S.; Kahl, W.K.

    1990-01-01

    In this paper we summarize preliminary results from applying a new mathematical technique -- chaotic time series analysis (CTSA) -- to cylinder pressure data from a spark-ignition (SI) four-stroke engine fueled with both methanol and iso-octane. Our objective is to look for the presence of deterministic chaos'' dynamics in peak pressure variations and to investigate the potential usefulness of CTSA as a diagnostic tool. Our results suggest that sequential peak cylinder pressures exhibit some characteristic features of deterministic chaos and that CTSA can extract previously unrecognized information from such data. 18 refs., 11 figs., 2 tabs.

  1. Analysis and synthesis of the variability of irradiance and PV power time series with the wavelet transform

    SciTech Connect (OSTI)

    Perpinan, O.; Lorenzo, E.

    2011-01-15

    The irradiance fluctuations and the subsequent variability of the power output of a PV system are analysed with some mathematical tools based on the wavelet transform. It can be shown that the irradiance and power time series are nonstationary process whose behaviour resembles that of a long memory process. Besides, the long memory spectral exponent {alpha} is a useful indicator of the fluctuation level of a irradiance time series. On the other side, a time series of global irradiance on the horizontal plane can be simulated by means of the wavestrapping technique on the clearness index and the fluctuation behaviour of this simulated time series correctly resembles the original series. Moreover, a time series of global irradiance on the inclined plane can be simulated with the wavestrapping procedure applied over a signal previously detrended by a partial reconstruction with a wavelet multiresolution analysis, and, once again, the fluctuation behaviour of this simulated time series is correct. This procedure is a suitable tool for the simulation of irradiance incident over a group of distant PV plants. Finally, a wavelet variance analysis and the long memory spectral exponent show that a PV plant behaves as a low-pass filter. (author)

  2. Experimental nonlinear dynamical studies in cesium magneto-optical trap using time-series analysis

    SciTech Connect (OSTI)

    Anwar, M. Islam, R.; Faisal, M.; Sikandar, M.; Ahmed, M.

    2015-03-30

    A magneto-optical trap of neutral atoms is essentially a dissipative quantum system. The fast thermal atoms continuously dissipate their energy to the environment via spontaneous emissions during the cooling. The atoms are, therefore, strongly coupled with the vacuum reservoir and the laser field. The vacuum fluctuations as well as the field fluctuations are imparted to the atoms as random photon recoils. Consequently, the external and internal dynamics of atoms becomes stochastic. In this paper, we have investigated the stochastic dynamics of the atoms in a magneto-optical trap during the loading process. The time series analysis of the fluorescence signal shows that the dynamics of the atoms evolves, like all dissipative systems, from deterministic to the chaotic regime. The subsequent disappearance and revival of chaos was attributed to chaos synchronization between spatially different atoms in the magneto-optical trap.

  3. THE EARLIEST NEAR-INFRARED TIME-SERIES SPECTROSCOPY OF A TYPE Ia SUPERNOVA

    SciTech Connect (OSTI)

    Hsiao, E. Y.; Phillips, M. M.; Morrell, N.; Contreras, C.; Roth, M.; Marion, G. H.; Kirshner, R. P.; Burns, C. R.; Freedman, W. L.; Persson, S. E.; Winge, C.; Gerardy, C. L.; Hoeflich, P.; Im, M.; Jeon, Y.; Pignata, G.; Stanishev, V.; and others

    2013-04-01

    We present ten medium-resolution, high signal-to-noise ratio near-infrared (NIR) spectra of SN 2011fe from SpeX on the NASA Infrared Telescope Facility (IRTF) and Gemini Near-Infrared Spectrograph (GNIRS) on Gemini North, obtained as part of the Carnegie Supernova Project. This data set constitutes the earliest time-series NIR spectroscopy of a Type Ia supernova (SN Ia), with the first spectrum obtained at 2.58 days past the explosion and covering -14.6 to +17.3 days relative to B-band maximum. C I {lambda}1.0693 {mu}m is detected in SN 2011fe with increasing strength up to maximum light. The delay in the onset of the NIR C I line demonstrates its potential to be an effective tracer of unprocessed material. For the first time in a SN Ia, the early rapid decline of the Mg II {lambda}1.0927 {mu}m velocity was observed, and the subsequent velocity is remarkably constant. The Mg II velocity during this constant phase locates the inner edge of carbon burning and probes the conditions under which the transition from deflagration to detonation occurs. We show that the Mg II velocity does not correlate with the optical light-curve decline rate {Delta}m{sub 15}(B). The prominent break at {approx}1.5 {mu}m is the main source of concern for NIR k-correction calculations. We demonstrate here that the feature has a uniform time evolution among SNe Ia, with the flux ratio across the break strongly correlated with {Delta}m{sub 15}(B). The predictability of the strength and the onset of this feature suggests that the associated k-correction uncertainties can be minimized with improved spectral templates.

  4. Modeling an Application's Theoretical Minimum and Average Transactional Response Times

    SciTech Connect (OSTI)

    Paiz, Mary Rose

    2015-04-01

    The theoretical minimum transactional response time of an application serves as a ba- sis for the expected response time. The lower threshold for the minimum response time represents the minimum amount of time that the application should take to complete a transaction. Knowing the lower threshold is beneficial in detecting anomalies that are re- sults of unsuccessful transactions. On the converse, when an application's response time falls above an upper threshold, there is likely an anomaly in the application that is causing unusual performance issues in the transaction. This report explains how the non-stationary Generalized Extreme Value distribution is used to estimate the lower threshold of an ap- plication's daily minimum transactional response time. It also explains how the seasonal Autoregressive Integrated Moving Average time series model is used to estimate the upper threshold for an application's average transactional response time.

  5. Real-Time Series Resistance Monitoring in PV Systems Without the Need for I-V Curves

    SciTech Connect (OSTI)

    Deceglie, Michael G.; Silverman, Timothy J.; Marion, Bill; Kurtz, Sarah R.

    2015-10-01

    We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting I-V curves or constructing full series resistance-free I-V curves. RTSR is most readily deployable at the module level on microinverters or module-integrated electronics, but it can also be extended to full strings. We found that automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We also describe the method in detail and describe a sample application to data collected from modules operating in the field.

  6. Correcting incompatible DN values and geometric errors in nighttime lights time series images

    SciTech Connect (OSTI)

    Zhao, Naizhuo; Zhou, Yuyu; Samson, Eric

    2015-04-01

    The Defense Meteorological Satellite Programs Operational Linescan System (DMSP-OLS) nighttime lights imagery has proven to be a powerful remote sensing tool to monitor urbanization and assess socioeconomic activities at large scales. However, the existence of incompatible digital number (DN) values and geometric errors severely limit application of nighttime light image data on multi-year quantitative research. In this study we extend and improve previous studies on inter-calibrating nighttime lights image data to obtain more compatible and reliable nighttime lights time series (NLT) image data for China and the United States (US) through four steps: inter-calibration, geometric correction, steady increase adjustment, and population data correction. We then use gross domestic product (GDP) data to test the processed NLT image data indirectly and find that sum light (summed DN value of pixels in a nighttime light image) maintains apparent increase trends with relatively large GDP growth rates but does not increase or decrease with relatively small GDP growth rates. As nighttime light is a sensitive indicator for economic activity, the temporally consistent trends between sum light and GDP growth rate imply that brightness of nighttime lights on the ground is correctly represented by the processed NLT image data. Finally, through analyzing the corrected NLT image data from 1992 to 2008, we find that China experienced apparent nighttime lights development in 1992-1997 and 2001-2008 respectively and the US suffered from nighttime lights decay in large areas after 2001.

  7. A Scientific Data Processing Framework for Time Series NetCDF Data

    SciTech Connect (OSTI)

    Gaustad, Krista L.; Shippert, Timothy R.; Ermold, Brian D.; Beus, Sherman J.; Daily, Jeffrey A.; Borsholm, Atle; Fox, Kevin M.

    2014-10-01

    ARM Data Integrator (ADI) is a framework to streamline the development of scientific algorithms that analyze time-series NetCDF data, and to improve the content and consistency of the output data products produced by these algorithms. ADI achieves these goals by automating the process of retrieving and preparing data for analysis, supporting the definition of output data products through a graphical interface, and providing a modular, flexible software development architecture. The input data, preprocessing, and output data specifications are defined through a graphical interface and stored in a database. ADI also includes a workflow for data integration, a library of software modules to support the workflow, and a source code generator that produces C, IDL and Python templates. Data preparation support includes automated retrieval of data from input files, merging the retrieved data into appropriately sized chunks, and transformation of the data onto a common coordinate system grid. Through the graphical interface, users can view the details of both their data products and those in the ARM catalog. The variable and attribute definitions of the existing data products can be used to build new output data products. In addition, the rules that make up the ARM archives data standards are laid on top of the view of the new data product providing the user with a visual cue indicating where their output violates an archive standard. The necessary configurations are stored in a database that is accessed by the ADI libraries. This paper discusses the ADI framework, its supporting components, and how ADI can significantly decrease the time and cost of implementing scientific algorithms while improving the ability of scientists to disseminate their results.

  8. Multivariate Spatio-Temporal Clustering of Times-Series Data: An Approach for Diagnosing Cloud Properties and Understandin...

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

    Multivariate Spatio-Temporal Clustering of Times-Series Data: An Approach for Diagnosing Cloud Properties and Understanding ARM Site Representativeness F. M. Hoffman and W. W. Hargrove Oak Ridge National Laboratory Oakridge, Tennessee A. D. Del Genio National Aeronautics and Space Administration Goddard Institute for Space Studies Columbia University, New York Multivariate Clustering A multivariate statistical clustering technique-based on the iterative k-means algorithm of Hartigan (Hartigan

  9. Six-Week Time Series Of Eddy Covariance CO2 Flux At Mammoth Mountain...

    Open Energy Info (EERE)

    high, spatially heterogeneous CO2 emission rates. EC CO2 fluxes ranged from 218 to 3500 g m- 2 d- 1 (mean 1346 g m- 2 d- 1). Using footprint modeling, EC CO2 fluxes were...

  10. Sediment transport time measured with U-Series isotopes: Resultsfrom ODP North Atlantic Drill Site 984

    SciTech Connect (OSTI)

    DePaolo, Donald J.; Maher, Kate; Christensen, John N.; McManus,Jerry

    2006-06-05

    High precision uranium isotope measurements of marineclastic sediments are used to measure the transport and storage time ofsediment from source to site of deposition. The approach is demonstratedon fine-grained, late Pleistocene deep-sea sediments from Ocean DrillingProgram Site 984A on the Bjorn Drift in the North Atlantic. The sedimentsare siliciclastic with up to 30 percent carbonate, and dated by sigma 18Oof benthic foraminifera. Nd and Sr isotopes indicate that provenance hasoscillated between a proximal source during the last three interglacialperiods volcanic rocks from Iceland and a distal continental sourceduring glacial periods. An unexpected finding is that the 234U/238Uratios of the silicate portion of the sediment, isolated by leaching withhydrochloric acid, are significantly less than the secular equilibriumvalue and show large and systematic variations that are correlated withglacial cycles and sediment provenance. The 234U depletions are inferredto be due to alpha-recoil loss of234Th, and are used to calculate"comminution ages" of the sediment -- the time elapsed between thegeneration of the small (<_ 50 mu-m) sediment grains in the sourceareas by comminution of bedrock, and the time of deposition on theseafloor. Transport times, the difference between comminution ages anddepositional ages, vary from less than 10 ky to about 300 to 400 ky forthe Site 984A sediments. Long transport times may reflect prior storagein soils, on continental shelves, or elsewhere on the seafloor. Transporttime may also be a measure of bottom current strength. During the mostrecent interglacial periods the detritus from distal continental sourcesis diluted with sediment from Iceland that is rapidly transported to thesite of deposition. The comminution age approach could be used to dateQuaternary non-marine sediments, soils, and atmospheric dust, and may beenhanced by concomitant measurement of 226Ra/230Th, 230Th/234U, andcosmogenic nuclides.

  11. Time series association learning

    DOE Patents [OSTI]

    Papcun, George J.

    1995-01-01

    An acoustic input is recognized from inferred articulatory movements output by a learned relationship between training acoustic waveforms and articulatory movements. The inferred movements are compared with template patterns prepared from training movements when the relationship was learned to regenerate an acoustic recognition. In a preferred embodiment, the acoustic articulatory relationships are learned by a neural network. Subsequent input acoustic patterns then generate the inferred articulatory movements for use with the templates. Articulatory movement data may be supplemented with characteristic acoustic information, e.g. relative power and high frequency data, to improve template recognition.

  12. X Time Series

    Energy Savers [EERE]

    ... agricultural tractors, combines, commercial airports, point sources, and heavy duty truck idling 2012 With Eagle Ford Emission Inventory WRF v3.2 CAMx 5.40 Local 2012 San ...

  13. An Approach to Integrate a Space-Time GIS Data Model with High Performance Computers

    SciTech Connect (OSTI)

    Wang, Dali; Zhao, Ziliang; Shaw, Shih-Lung

    2011-01-01

    In this paper, we describe an approach to integrate a Space-Time GIS data model on a high performance computing platform. The Space-Time GIS data model has been developed on a desktop computing environment. We use the Space-Time GIS data model to generate GIS module, which organizes a series of remote sensing data. We are in the process of porting the GIS module into an HPC environment, in which the GIS modules handle large dataset directly via parallel file system. Although it is an ongoing project, authors hope this effort can inspire further discussions on the integration of GIS on high performance computing platforms.

  14. Time-series product and substance flow analyses of end-of-life electrical and electronic equipment in China

    SciTech Connect (OSTI)

    Habuer, Nakatani, Jun; Moriguchi, Yuichi

    2014-02-15

    Highlights: We estimate the possession and obsolescence of household appliances (HAs) in China. Over 4.85.1 billion units of major HAs will be discarded in the next 20 years. We calculate the amounts of substances contained in end-of-life (EoL) TV sets. Less common metals will tend to decrease in content in generation of EoL TV sets. Precious metals will tend to increase in content in EoL TV sets in 20152030. - Abstract: Given the amounts of end-of-life electrical and electronic equipment (EoL-EEE) being generated and their contents of both harmful and valuable materials, the EoL-EEE issue should be regarded not only as an emerging environmental problem but also as a resource management strategy in China. At present, in order to provide the basis for managing EoL-EEE at both product and substance levels in China, it is necessary to carry out a quantitative analysis on EoL-EEE and to determine how much of it will be generated and how much materials and substances it contains. In this study, the possession and obsolescence amounts of five types of household appliance (HA) including television (TV) sets and the amounts of substances contained in EoL TV sets were estimated using time-series product flow analysis (PFA) and substance flow analysis (SFA). The results of PFA indicated that the total possession amounts of those five types of HAs will exceed 3.1 billion units in 2030, which will be two times higher than those in 2010. In addition, it was estimated that cumulatively over 4.85.1 billion units of these five types of EoL HA would be obsoleted between 20102030. The results of SFA on TV sets indicated that the generated amounts of most of the less common metals and a part of common metals such as copper (Cu) would tend to decrease, whereas those of other common metals such as iron (Fe) as well as precious metals would tend to increase in EoL TV sets in 20152030. The results of this study provide a quantitative basis for helping decision makers

  15. Two-parameter double-oscillator model of Mathews-Lakshmanan type: Series solutions and supersymmetric partners

    SciTech Connect (OSTI)

    Schulze-Halberg, Axel E-mail: xbataxel@gmail.com; Wang, Jie

    2015-07-15

    We obtain series solutions, the discrete spectrum, and supersymmetric partners for a quantum double-oscillator system. Its potential features a superposition of the one-parameter Mathews-Lakshmanan interaction and a one-parameter harmonic or inverse harmonic oscillator contribution. Furthermore, our results are transferred to a generalized Pöschl-Teller model that is isospectral to the double-oscillator system.

  16. Modeling highway travel time distribution with conditional probability models

    SciTech Connect (OSTI)

    Oliveira Neto, Francisco Moraes; Chin, Shih-Miao; Hwang, Ho-Ling; Han, Lee

    2014-01-01

    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).

  17. Analysis of High Precision GPS Time Series and Strain Rates for the Geothermal Play Fairway Analysis of Washington State Prospects Project

    SciTech Connect (OSTI)

    Michael Swyer

    2015-02-22

    Global Positioning System (GPS) time series from the National Science Foundation (NSF) Earthscope’s Plate Boundary Observatory (PBO) and Central Washington University’s Pacific Northwest Geodetic Array (PANGA). GPS station velocities were used to infer strain rates using the ‘splines in tension’ method. Strain rates were derived separately for subduction zone locking at depth and block rotation near the surface within crustal block boundaries.

  18. Analysis of High Precision GPS Time Series and Strain Rates for the Geothermal Play Fairway Analysis of Washington State Prospects Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Michael Swyer

    2015-02-22

    Global Positioning System (GPS) time series from the National Science Foundation (NSF) Earthscopes Plate Boundary Observatory (PBO) and Central Washington Universitys Pacific Northwest Geodetic Array (PANGA). GPS station velocities were used to infer strain rates using the splines in tension method. Strain rates were derived separately for subduction zone locking at depth and block rotation near the surface within crustal block boundaries.

  19. Snyder-de Sitter model from two-time physics

    SciTech Connect (OSTI)

    Carrisi, M. C.; Mignemi, S.

    2010-11-15

    We show that the symplectic structure of the Snyder model on a de Sitter background can be derived from two-time physics in seven dimensions and propose a Hamiltonian for a free particle consistent with the symmetries of the model.

  20. Time-series analysis of ion and isotope geochemistry of selected springs of the Nevada Test Site, Nye County, Nevada

    SciTech Connect (OSTI)

    Lyles, B.F.; Edkins, J.; Jacobson, R.L.; Hess, J.W.

    1990-11-01

    The temporal variations of ion and isotope geochemistry were observed at six selected springs on the Nevada Test Site, Nye County, Nevada and included: Cane, Whiterock, Captain Jack, Topopah, Tippipah, and Oak Springs. The sites were monitored from 1980 to 1982 and the following parameters were measured: temperature, pH, electrical conductance, discharge, cations (Ca{sup 2+}, Mg{sup 2+}. Na{sup +}, K{sup +}), anions Cl{sup {minus}}, SO{sub 4}{sup 2{minus}}. HCO{sub 3}{sup {minus}}, silica, stable isotopes ({delta}{sup 18}O, {delta}D, {delta}{sup 13}C), and radioactive isotopes ({sup 3}H, {sup 14}C). A more detailed study was continued from 1982 to 1988 at Cane and Whiterock Springs. Field microloggers were installed at these sites in 1985 to measure the high frequency response of temperature, electrical conductance, and discharge to local precipitation. Stage fluctuations near the discharge point dissolve minerals/salts as groundwater inundates the mineralized zone immediately above the equilibrium water table. This phenomena was most noticeable at Whiterock Spring and lagged the discharge response by several hours. Stable isotope analysis of precipitation and groundwater suggests a 1.5 to 2 month travel time for meteoric water to migrate from the recharge area to the discharge point. Groundwater age determinations suggest a mean age of approximately 30 years at Whiterock Spring and possibly older at Cane Spring. However, the short travel time and geochemical integrity of recharge pulses suggest that the waters are poorly mixed along the flow paths. 25 refs., 25 figs., 24 tabs.

  1. Modeling of Time Varying Slag Flow in Coal Gasifiers

    SciTech Connect (OSTI)

    Pilli, Siva Prasad; Johnson, Kenneth I.; Williford, Ralph E.; Sundaram, S. K.; Korolev, Vladimir N.; Crum, Jarrod V.

    2008-08-30

    There is considerable interest within government agencies and the energy industries across the globe to further advance the clean and economical conversion of coal into liquid fuels to reduce our dependency on imported oil. To date, advances in these areas have been largely based on experimental work. Although there are some detailed systems level performance models, little work has been done on numerical modeling of the component level processes. If accurate models are developed, then significant R&D time might be saved, new insights into the process might be gained, and some good predictions of process or performance can be made. One such area is the characterization of slag deposition and flow on the gasifier walls. Understanding slag rheology and slag-refractory interactions is critical to design and operation of gasifiers with extended refractory lifetimes and also to better control of operating parameters so that the overall gasifier performance with extended service life can be optimized. In the present work, the literature on slag flow modeling was reviewed and a model similar to Seggiani’s was developed to simulate the time varying slag accumulation and flow on the walls of a Prenflo coal gasifier. This model was further extended and modified to simulate a refractory wall gasifier including heat transfer through the refractory wall with flowing slag in contact with the refractory. The model was used to simulate temperature dependent slag flow using rheology data from our experimental slag testing program. These modeling results as well as experimental validation are presented.

  2. Short-term Time Step Convergence in a Climate Model

    SciTech Connect (OSTI)

    Wan, Hui; Rasch, Philip J.; Taylor, Mark; Jablonowski, Christiane

    2015-02-11

    A testing procedure is designed to assess the convergence property of a global climate model with respect to time step size, based on evaluation of the root-mean-square temperature difference at the end of very short (1 h) simulations with time step sizes ranging from 1 s to 1800 s. A set of validation tests conducted without sub-grid scale parameterizations confirmed that the method was able to correctly assess the convergence rate of the dynamical core under various configurations. The testing procedure was then applied to the full model, and revealed a slow convergence of order 0.4 in contrast to the expected first-order convergence. Sensitivity experiments showed without ambiguity that the time stepping errors in the model were dominated by those from the stratiform cloud parameterizations, in particular the cloud microphysics. This provides a clear guidance for future work on the design of more accurate numerical methods for time stepping and process coupling in the model.

  3. Neutrino flavor instabilities in a time-dependent supernova model

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

    Abbar, Sajad; Duan, Huaiyu

    2015-10-19

    In this study, a dense neutrino medium such as that inside a core-collapse supernova can experience collective flavor conversion or oscillations because of the neutral-current weak interaction among the neutrinos. This phenomenon has been studied in a restricted, stationary supernova model which possesses the (spatial) spherical symmetry about the center of the supernova and the (directional) axial symmetry around the radial direction. Recently it has been shown that these spatial and directional symmetries can be broken spontaneously by collective neutrino oscillations. In this letter we analyze the neutrino flavor instabilities in a time-dependent supernova model. Our results show that collectivemore »neutrino oscillations start at approximately the same radius in both the stationary and time-dependent supernova models unless there exist very rapid variations in local physical conditions on timescales of a few microseconds or shorter. Our results also suggest that collective neutrino oscillations can vary rapidly with time in the regimes where they do occur which need to be studied in time-dependent supernova models.« less

  4. Short-term time step convergence in a climate model

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

    Wan, Hui; Rasch, Philip J.; Taylor, Mark; Jablonowski, Christiane

    2015-02-11

    A testing procedure is designed to assess the convergence property of a global climate model with respect to time step size, based on evaluation of the root-mean-square temperature difference at the end of very short (1 h) simulations with time step sizes ranging from 1 s to 1800 s. A set of validation tests conducted without sub-grid scale parameterizations confirmed that the method was able to correctly assess the convergence rate of the dynamical core under various configurations. The testing procedure was then applied to the full model, and revealed a slow convergence of order 0.4 in contrast to themoreexpected first-order convergence. Sensitivity experiments showed without ambiguity that the time stepping errors in the model were dominated by those from the stratiform cloud parameterizations, in particular the cloud microphysics. This provides a clear guidance for future work on the design of more accurate numerical methods for time stepping and process coupling in the model.less

  5. Short-term Time Step Convergence in a Climate Model

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

    Wan, Hui; Rasch, Philip J.; Taylor, Mark; Jablonowski, Christiane

    2015-02-11

    A testing procedure is designed to assess the convergence property of a global climate model with respect to time step size, based on evaluation of the root-mean-square temperature difference at the end of very short (1 h) simulations with time step sizes ranging from 1 s to 1800 s. A set of validation tests conducted without sub-grid scale parameterizations confirmed that the method was able to correctly assess the convergence rate of the dynamical core under various configurations. The testing procedure was then applied to the full model, and revealed a slow convergence of order 0.4 in contrast to themore » expected first-order convergence. Sensitivity experiments showed without ambiguity that the time stepping errors in the model were dominated by those from the stratiform cloud parameterizations, in particular the cloud microphysics. This provides a clear guidance for future work on the design of more accurate numerical methods for time stepping and process coupling in the model.« less

  6. VisIO: enabling interactive visualization of ultra-scale, time-series data via high-bandwidth distributed I/O systems

    SciTech Connect (OSTI)

    Mitchell, Christopher J; Ahrens, James P; Wang, Jun

    2010-10-15

    Petascale simulations compute at resolutions ranging into billions of cells and write terabytes of data for visualization and analysis. Interactive visuaUzation of this time series is a desired step before starting a new run. The I/O subsystem and associated network often are a significant impediment to interactive visualization of time-varying data; as they are not configured or provisioned to provide necessary I/O read rates. In this paper, we propose a new I/O library for visualization applications: VisIO. Visualization applications commonly use N-to-N reads within their parallel enabled readers which provides an incentive for a shared-nothing approach to I/O, similar to other data-intensive approaches such as Hadoop. However, unlike other data-intensive applications, visualization requires: (1) interactive performance for large data volumes, (2) compatibility with MPI and POSIX file system semantics for compatibility with existing infrastructure, and (3) use of existing file formats and their stipulated data partitioning rules. VisIO, provides a mechanism for using a non-POSIX distributed file system to provide linear scaling of 110 bandwidth. In addition, we introduce a novel scheduling algorithm that helps to co-locate visualization processes on nodes with the requested data. Testing using VisIO integrated into Para View was conducted using the Hadoop Distributed File System (HDFS) on TACC's Longhorn cluster. A representative dataset, VPIC, across 128 nodes showed a 64.4% read performance improvement compared to the provided Lustre installation. Also tested, was a dataset representing a global ocean salinity simulation that showed a 51.4% improvement in read performance over Lustre when using our VisIO system. VisIO, provides powerful high-performance I/O services to visualization applications, allowing for interactive performance with ultra-scale, time-series data.

  7. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    SciTech Connect (OSTI)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim; Gilbert, Bob; Lake, Larry W.; Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett; Thomas, Sunil G.; Rightley, Michael J.; Rodriguez, Adolfo; Klie, Hector; Banchs, Rafael; Nunez, Emilio J.; Jablonowski, Chris

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  8. Preliminary time-phased TWRS process model results

    SciTech Connect (OSTI)

    Orme, R.M.

    1995-03-24

    This report documents the first phase of efforts to model the retrieval and processing of Hanford tank waste within the constraints of an assumed tank farm configuration. This time-phased approach simulates a first try at a retrieval sequence, the batching of waste through retrieval facilities, the batching of retrieved waste through enhanced sludge washing, the batching of liquids through pretreatment and low-level waste (LLW) vitrification, and the batching of pretreated solids through high-level waste (HLW) vitrification. The results reflect the outcome of an assumed retrieval sequence that has not been tailored with respect to accepted measures of performance. The batch data, composition variability, and final waste volume projects in this report should be regarded as tentative. Nevertheless, the results provide interesting insights into time-phased processing of the tank waste. Inspection of the composition variability, for example, suggests modifications to the retrieval sequence that will further improve the uniformity of feed to the vitrification facilities. This model will be a valuable tool for evaluating suggested retrieval sequences and establishing a time-phased processing baseline. An official recommendation on tank retrieval sequence will be made in September, 1995.

  9. TIME-DEPENDENT MODELING OF PULSAR WIND NEBULAE

    SciTech Connect (OSTI)

    Vorster, M. J.; Ferreira, S. E. S.; Tibolla, O.; Kaufmann, S. E-mail: omar.tibolla@gmail.com

    2013-08-20

    A spatially independent model that calculates the time evolution of the electron spectrum in a spherically expanding pulsar wind nebula (PWN) is presented, allowing one to make broadband predictions for the PWN's non-thermal radiation. The source spectrum of electrons injected at the termination shock of the PWN is chosen to be a broken power law. In contrast to previous PWN models of a similar nature, the source spectrum has a discontinuity in intensity at the transition between the low- and high-energy components. To test the model, it is applied to the young PWN G21.5-0.9, where it is found that a discontinuous source spectrum can model the emission at all wavelengths better than a continuous one. The model is also applied to the unidentified sources HESS J1427-608 and HESS J1507-622. Parameters are derived for these two candidate nebulae that are consistent with the values predicted for other PWNe. For HESS J1427-608, a present day magnetic field of B{sub age} = 0.4 {mu}G is derived. As a result of the small present day magnetic field, this source has a low synchrotron luminosity, while remaining bright at GeV/TeV energies. It is therefore possible to interpret HESS J1427-608 within the ancient PWN scenario. For the second candidate PWN HESS J1507-622, a present day magnetic field of B{sub age} = 1.7 {mu}G is derived. Furthermore, for this candidate PWN a scenario is favored in the present paper in which HESS J1507-622 has been compressed by the reverse shock of the supernova remnant.

  10. Seminar Series

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

    Seminar Series Seminar Series The IS&T seminars on various information science and technology topics are held every Wednesday from 3-4 PM at the CNLS Conference Room unless otherwise noted. Contact Institute Director Stephan Eidenbenz (505) 667-3742 Email Professional Staff Assistant Nickole Aguilar Garcia (505) 665-3048 Email To schedule a speaker please contact the Nickole Garcia. To subscribe to the IS&T seminar announcements please use the Program Announcement tool什(Use win domain

  11. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: I. Model implementation

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

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-24

    We explore optimization methods for planning the placement, sizing and operations of Flexible Alternating Current Transmission System (FACTS) devices installed to relieve transmission grid congestion. We limit our selection of FACTS devices to Series Compensation (SC) devices that can be represented by modification of the inductance of transmission lines. Our master optimization problem minimizes the l1 norm of the inductance modification subject to the usual line thermal-limit constraints. We develop heuristics that reduce this non-convex optimization to a succession of Linear Programs (LP) which are accelerated further using cutting plane methods. The algorithm solves an instance of the MatPower Polishmore » Grid model (3299 lines and 2746 nodes) in 40 seconds per iteration on a standard laptop—a speed up that allows the sizing and placement of a family of SC devices to correct a large set of anticipated congestions. We observe that our algorithm finds feasible solutions that are always sparse, i.e., SC devices are placed on only a few lines. In a companion manuscript, we demonstrate our approach on realistically-sized networks that suffer congestion from a range of causes including generator retirement. In this manuscript, we focus on the development of our approach, investigate its structure on a small test system subject to congestion from uniform load growth, and demonstrate computational efficiency on a realistically-sized network.« less

  12. Efficient algorithm for locating and sizing series compensation devices in large power transmission grids: I. Model implementation

    SciTech Connect (OSTI)

    Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha

    2014-10-24

    We explore optimization methods for planning the placement, sizing and operations of Flexible Alternating Current Transmission System (FACTS) devices installed to relieve transmission grid congestion. We limit our selection of FACTS devices to Series Compensation (SC) devices that can be represented by modification of the inductance of transmission lines. Our master optimization problem minimizes the l1 norm of the inductance modification subject to the usual line thermal-limit constraints. We develop heuristics that reduce this non-convex optimization to a succession of Linear Programs (LP) which are accelerated further using cutting plane methods. The algorithm solves an instance of the MatPower Polish Grid model (3299 lines and 2746 nodes) in 40 seconds per iteration on a standard laptop—a speed up that allows the sizing and placement of a family of SC devices to correct a large set of anticipated congestions. We observe that our algorithm finds feasible solutions that are always sparse, i.e., SC devices are placed on only a few lines. In a companion manuscript, we demonstrate our approach on realistically-sized networks that suffer congestion from a range of causes including generator retirement. In this manuscript, we focus on the development of our approach, investigate its structure on a small test system subject to congestion from uniform load growth, and demonstrate computational efficiency on a realistically-sized network.

  13. Efficient Algorithm for Locating and Sizing Series Compensation Devices in Large Transmission Grids: Model Implementation (PART 1)

    SciTech Connect (OSTI)

    Frolov, Vladimir; Backhaus, Scott N.; Chertkov, Michael

    2014-01-14

    We explore optimization methods for planning the placement, sizing and operations of Flexible Alternating Current Transmission System (FACTS) devices installed to relieve transmission grid congestion. We limit our selection of FACTS devices to Series Compensation (SC) devices that can be represented by modification of the inductance of transmission lines. Our master optimization problem minimizes the l1 norm of the inductance modification subject to the usual line thermal-limit constraints. We develop heuristics that reduce this non-convex optimization to a succession of Linear Programs (LP) which are accelerated further using cutting plane methods. The algorithm solves an instance of the MatPower Polish Grid model (3299 lines and 2746 nodes) in 40 seconds per iteration on a standard laptop—a speed up that allows the sizing and placement of a family of SC devices to correct a large set of anticipated congestions. We observe that our algorithm finds feasible solutions that are always sparse, i.e., SC devices are placed on only a few lines. In a companion manuscript, we demonstrate our approach on realistically-sized networks that suffer congestion from a range of causes including generator retirement. In this manuscript, we focus on the development of our approach, investigate its structure on a small test system subject to congestion from uniform load growth, and demonstrate computational efficiency on a realistically-sized network.

  14. TIME-SERIES PHOTOMETRY OF GLOBULAR CLUSTERS: M62 (NGC 6266), THE MOST RR LYRAE-RICH GLOBULAR CLUSTER IN THE GALAXY?

    SciTech Connect (OSTI)

    Contreras, R.; Catelan, M.; Smith, H. A.; Kuehn, C. A.; Pritzl, B. J.; Borissova, J.

    2010-12-15

    We present new time-series CCD photometry, in the B and V bands, for the moderately metal-rich ([Fe/H] {approx_equal} -1.3) Galactic globular cluster M62 (NGC 6266). The present data set is the largest obtained so far for this cluster and consists of 168 images per filter, obtained with the Warsaw 1.3 m telescope at the Las Campanas Observatory and the 1.3 m telescope of the Cerro Tololo Inter-American Observatory, in two separate runs over the time span of 3 months. The procedure adopted to detect the variable stars was the optimal image subtraction method (ISIS v2.2), as implemented by Alard. The photometry was performed using both ISIS and Stetson's DAOPHOT/ALLFRAME package. We have identified 245 variable stars in the cluster fields that have been analyzed so far, of which 179 are new discoveries. Of these variables, 133 are fundamental mode RR Lyrae stars (RRab), 76 are first overtone (RRc) pulsators, 4 are type II Cepheids, 25 are long-period variables (LPVs), 1 is an eclipsing binary, and 6 are not yet well classified. Such a large number of RR Lyrae stars places M62 among the top two most RR Lyrae-rich (in the sense of total number of RR Lyrae stars present) globular clusters known in the Galaxy, second only to M3 (NGC 5272) with a total of 230 known RR Lyrae stars. Since this study covers most but not all of the cluster area, it is not unlikely that M62 is in fact the most RR Lyrae-rich globular cluster in the Galaxy. In like vein, thanks to the time coverage of our data sets, we were also able to detect the largest sample of LPVs known so far in a Galactic globular cluster. We analyze a variety of Oosterhoff type indicators for the cluster, including mean periods, period distribution, Bailey diagrams, and Fourier decomposition parameters (as well as the physical parameters derived therefrom). All of these indicators clearly show that M62 is an Oosterhoff type I system. This is in good agreement with the moderately high metallicity of the cluster, in spite

  15. Time series monitoring of water quality and microalgal diversity in a tropical bay under intense anthropogenic interference (SW coast of the Bay of Bengal, India)

    SciTech Connect (OSTI)

    Shaik, Aziz ur Rahman; Biswas, Haimanti; Reddy, N.P.C.; Srinivasa Rao, V.; Bharathi, M.D.; Subbaiah, Ch.V.

    2015-11-15

    In recent decades, material fluxes to coastal waters from various land based anthropogenic activities have significantly been enhanced around the globe which can considerably impact the coastal water quality and ecosystem health. Hence, there is a critical need to understand the links between anthropogenic activities in watersheds and its health. Kakinada Bay is situated at the SW part of the Bay of Bengal, near to the second largest mangrove cover in India with several fertilizer industries along its bank and could be highly vulnerable to different types of pollutants. However, virtually, no data is available so far reporting its physicochemical status and microalgal diversity at this bay. In order to fill this gap, we conducted three time series observations at a fixed station during January, December and June 2012, at this bay measuring more than 15 physical, chemical and biological parameters in every 3 h over a period of 36 h in both surface (0 m) and subsurface (4.5 m) waters. Our results clearly depict a strong seasonality between three sampling months; however, any abnormal values of nutrients, biological oxygen demand or dissolved oxygen level was not observed. A Skeletonema costatum bloom was observed in December which was probably influenced by low saline, high turbid and high Si input through the river discharge. Otherwise, smaller diatoms like Thalassiosira decipiens, Thalassiothrix frauenfeldii, and Thalassionema nitzschioides dominated the bay. It is likely that the material loading can be high at the point sources due to intense anthropogenic activities, however, gets diluted with biological, chemical and physical processes in the offshore waters. - Highlights: • No signature of enormous nutrient loading was observed over the diel cycle • Dissolved oxygen and BOD concentrations did not show any exceptional trend • Diatoms dominated more than 90% of the total phytoplankton communities • A Skeletonema Costatum (a centric diatom) bloom was

  16. Modeling fast electron dynamics with real-time time-dependent...

    Office of Scientific and Technical Information (OSTI)

    Lett. 2005, 94, 043002, demonstrating the utility of a real-time approach in capturing charge transfer processes. Authors: Lopata, Kenneth A. ; Govind, Niranjan Publication Date: ...

  17. Soil Series

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

    0 Soil Series and Phase D Bae D Da rn Fa D FuB D LuB ~ 09 _ Pk _ TrB _ TuE DUo _ vee D VeD o o * '='1 ~*.1* **..oC'" ~) OJ rI.:) o.Q 600 1200 Soils n O~:-* ilL 10., 1800 O~ c? ~ 0 ~ O~ Community _ Loblolly Pine D Mixed Pine/Hardwood o Upland Hardwood D Bottomland Hardwood _ Water a Bottomland HardwoodlPine o Monitoringwells .._.' *** TES Plants (1) :l!.-.~I ... 0 TES Plants (2) :='.Y-r::.: ~ Streams ){" ~ Rails . :1'\;:'/ Utility ROW ""If WasteSItes III NPDES outfalls CZI

  18. Nonlinear Time Domain Modeling and Simulation of Surface and...

    Office of Environmental Management (EM)

    Jose Abell, Kohei Watanabe, Chao Luo University of California, Davis Lawrence Berkeley National Laboratory, Berkeley DOE NPH, October 2014 PDF icon Nonlinear Time Domain...

  19. Series A.

    Office of Legacy Management (LM)

    clue to 2-n t3 ;rsence of copper and tin which is used a6 a coat over the ... (8) (9) (101 -2- Hot dip in alloy of 47% copper, 53% tin - temperature, 7CWC - time, ...

  20. Six-week time series of eddy covariance CO2 flux at Mammoth Mountain, California: performance evaluation and role of meteorological forcing

    SciTech Connect (OSTI)

    Lewicki, Jennifer; Lewicki, J.L.; Fischer, M.L.; Hilley, G.E.

    2007-10-15

    CO{sub 2} and heat fluxes were measured over a six-week period (09/08/2006 to 10/24/2006) by the eddy covariance (EC) technique at the Horseshoe Lake tree kill (HLTK), Mammoth Mountain, CA, a site with complex terrain and high, spatially heterogeneous CO{sub 2} emission rates. EC CO{sub 2} fluxes ranged from 218 to 3500 g m{sup -2} d{sup -1} (mean = 1346 g m{sup -2} d{sup -1}). Using footprint modeling, EC CO{sub 2} fluxes were compared to CO{sub 2} fluxes measured by the chamber method on a grid repeatedly over a 10-day period. Half-hour EC CO{sub 2} fluxes were moderately correlated (R{sup 2} = 0.42) with chamber fluxes, whereas average-daily EC CO{sub 2} fluxes were well correlated (R{sup 2} = 0.70) with chamber measurements. Average daily EC CO{sub 2} fluxes were correlated with both average daily wind speed and atmospheric pressure; relationships were similar to those observed between chamber CO{sub 2} fluxes and the atmospheric parameters over a comparable time period. Energy balance closure was assessed by statistical regression of EC energy fluxes (sensible and latent heat) against available energy (net radiation, less soil heat flux). While incomplete (R{sup 2} = 0.77 for 1:1 line), the degree of energy balance closure fell within the range observed in many investigations conducted in contrasting ecosystems and climates. Results indicate that despite complexities presented by the HLTK, EC can be reliably used to monitor background variations in volcanic CO{sub 2} fluxes associated with meteorological forcing, and presumably changes related to deeply derived processes such as volcanic activity.

  1. Time

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

    3 4 5 6 7 8 9 10 Time with respect to the BNB Trigger Time [µs] 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Fractional Flash Count per 0.15 µs with respect to Cosmic Background Measured Cosmic Rate (Beam-Off) BNB Trigger Data (Beam-On) [4.51E18 POT]

  2. Time

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

    10 15 20 Time with respect to the NuMI Trigger Time [µs] 0.9 1.0 1.1 1.2 1.3 1.4 1.5 Fractional Flash Count per 0.5 µs with respect to Cosmic Background Measured Cosmic Rate (Beam-Off) NuMI Trigger Data (Beam-On) [4.83E18 POT]

  3. First-time measurements will advance turbulence models

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

    Conditions for Stockpile Stewardship | National Nuclear Security Administration | (NNSA) First-of-its-Kind NNSA Capability to Support Study of Materials at Extreme Conditions for Stockpile Stewardship August 04, 2016 WASHINGTON - A new first-of-its-kind-worldwide research capability will help unravel the mysteries of material behavior at extreme conditions and short time scales in support of the Department of Energy's National Nuclear Security Administration's (DOE/NNSA's) vital national

  4. Method of modeling transmissions for real-time simulation

    DOE Patents [OSTI]

    Hebbale, Kumaraswamy V.

    2012-09-25

    A transmission modeling system includes an in-gear module that determines an in-gear acceleration when a vehicle is in gear. A shift module determines a shift acceleration based on a clutch torque when the vehicle is shifting between gears. A shaft acceleration determination module determines a shaft acceleration based on at least one of the in-gear acceleration and the shift acceleration.

  5. Space-time complexity in solid state models

    SciTech Connect (OSTI)

    Bishop, A.R.

    1985-01-01

    In this Workshop on symmetry-breaking it is appropriate to include the evolving fields of nonlinear-nonequilibrium systems in which transitions to and between various degrees of ''complexity'' (including ''chaos'') occur in time or space or both. These notions naturally bring together phenomena of pattern formation and chaos and therefore have ramifications for a huge array of natural sciences - astrophysics, plasmas and lasers, hydrodynamics, field theory, materials and solid state theory, optics and electronics, biology, pattern recognition and evolution, etc. Our particular concerns here are with examples from solid state and condensed matter.

  6. Search Method for Real-time Knowledge Discovery Modeled on the...

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

    Search Method for Real-time Knowledge Discovery Modeled on the Human Brain Oak Ridge ... information processing properties of the human brain to computational knowledge discovery. ...

  7. Field Quality Study of the LARP Nb3Sn 3.7m-Long Quadrupole Models of LQ Series

    SciTech Connect (OSTI)

    AMbrosio, G.; Andreev, N.; Bossert, R.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Prebys, E.; Sylvester, C.; Tartaglia, M.; /Fermilab /LBL, Berkeley /Brookhaven

    2011-09-01

    After the successful test of the first long Nb{sub 3}Sn quadrupole magnet (LQS01), the US LHC Accelerator Research Program (LARP) has assembled and tested a new 3.7 m-long Nb{sub 3}Sn quadrupole (LQS02). This magnet has four new coils made of the same conductor as LQS01 coils, and it is using the same support structure. LQS02 was tested at the Fermilab Vertical Magnet Test Facility with the main goal to confirm that the long models can achieve field gradient above 200 T/m, LARP target for 90-mm aperture, as well as to measure the field quality. These long models lack some alignment features and it is important to study the field harmonics. Previous field quality measurements of LQS01 showed higher than expected differences between measured and calculated harmonics compared to the short models (TQS) assembled in a similar structure. These differences could be explained by the use of two different impregnation fixtures during coil fabrication. In this paper, we present a comparison of the field quality measurements between LQS01 and LQS02 as well as a comparison with the short TQS models. If the result supports the coil fabrication hypothesis, another LQS assembly with all coils fabricated in the same fixture will be produced for understanding the cause of the discrepancy between short and long models.

  8. Proposed SPAR Modeling Method for Quantifying Time Dependent Station Blackout Cut Sets

    SciTech Connect (OSTI)

    John A. Schroeder

    2010-06-01

    Abstract: The U.S. Nuclear Regulatory Commissions (USNRCs) Standardized Plant Analysis Risk (SPAR) models and industry risk models take similar approaches to analyzing the risk associated with loss of offsite power and station blackout (LOOP/SBO) events at nuclear reactor plants. In both SPAR models and industry models, core damage risk resulting from a LOOP/SBO event is analyzed using a combination of event trees and fault trees that produce cut sets that are, in turn, quantified to obtain a numerical estimate of the resulting core damage risk. A proposed SPAR method for quantifying the time-dependent cut sets is sometimes referred to as a convolution method. The SPAR method reflects assumptions about the timing of emergency diesel failures, the timing of subsequent attempts at emergency diesel repair, and the timing of core damage that may be different than those often used in industry models. This paper describes the proposed SPAR method.

  9. Focus Series | Department of Energy

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

    Focus Series Focus Series On-Bill Financing Brings Lenders and Homeowners on Board Photo of a man, woman, and small child standing in front of a house. Read how Clean Energy Works' partnership with a nonprofit community development financial institution resulted in an unprecedented number of upgrades in a short period of time. July 2014 Energy Advisors Help Homeowners Go the Extra Mile Advertisement for the Denver Energy Challenge, with a female smiling at the camera -- with something wrong with

  10. Toward Real-time Modeling of Human Heart Ventricles at Cellular...

    Office of Scientific and Technical Information (OSTI)

    Simulation of Drug-induced Arrhythmias Citation Details In-Document Search Title: Toward Real-time Modeling of Human Heart Ventricles at Cellular Resolution: Multi-hour Simulation ...

  11. Nonlinear Time Domain Modeling and Simulation of Surface and Embedded NPPS

    Broader source: Energy.gov [DOE]

    Nonlinear Time Domain Modeling and Simulation of Surface and Embedded NPPS Boris Jeremic with contributions from Federico Pisanò, Jose Abell, Kohei Watanabe, Chao Luo University of California, Davis Lawrence Berkeley National Laboratory, Berkeley DOE NPH, October 2014

  12. Method for determination of .sup.18 O/.sup.16 O and .sup.2 H/.sup.1 H ratios and .sup.3 H (tritium) concentrations of xylem waters and subsurface waters using time series sampling

    DOE Patents [OSTI]

    Smith, Brian; Menchaca, Leticia

    1999-01-01

    A method for determination of .sup.18 O/.sup.16 O and .sup.2 H/.sup.1 H ratios and .sup.3 H concentrations of xylem and subsurface waters using time series sampling, insulating sampling chambers, and combined .sup.18 O/.sup.16 O, .sup.2 H/.sup.1 H and .sup.3 H concentration data on transpired water. The method involves collecting water samples transpired from living plants and correcting the measured isotopic compositions of oxygen (.sup.18 O/.sup.16 O) and hydrogen (.sup.2 H/.sup.1 H and/or .sup.3 H concentrations) to account for evaporative isotopic fractionation in the leafy material of the plant.

  13. Dynamic force matching: A method for constructing dynamical coarse-grained models with realistic time dependence

    SciTech Connect (OSTI)

    Davtyan, Aram; Dama, James F.; Voth, Gregory A.; Andersen, Hans C.

    2015-04-21

    Coarse-grained (CG) models of molecular systems, with fewer mechanical degrees of freedom than an all-atom model, are used extensively in chemical physics. It is generally accepted that a coarse-grained model that accurately describes equilibrium structural properties (as a result of having a well constructed CG potential energy function) does not necessarily exhibit appropriate dynamical behavior when simulated using conservative Hamiltonian dynamics for the CG degrees of freedom on the CG potential energy surface. Attempts to develop accurate CG dynamic models usually focus on replacing Hamiltonian motion by stochastic but Markovian dynamics on that surface, such as Langevin or Brownian dynamics. However, depending on the nature of the system and the extent of the coarse-graining, a Markovian dynamics for the CG degrees of freedom may not be appropriate. In this paper, we consider the problem of constructing dynamic CG models within the context of the Multi-Scale Coarse-graining (MS-CG) method of Voth and coworkers. We propose a method of converting a MS-CG model into a dynamic CG model by adding degrees of freedom to it in the form of a small number of fictitious particles that interact with the CG degrees of freedom in simple ways and that are subject to Langevin forces. The dynamic models are members of a class of nonlinear systems interacting with special heat baths that were studied by Zwanzig [J. Stat. Phys. 9, 215 (1973)]. The properties of the fictitious particles can be inferred from analysis of the dynamics of all-atom simulations of the system of interest. This is analogous to the fact that the MS-CG method generates the CG potential from analysis of equilibrium structures observed in all-atom simulation data. The dynamic models generate a non-Markovian dynamics for the CG degrees of freedom, but they can be easily simulated using standard molecular dynamics programs. We present tests of this method on a series of simple examples that demonstrate that

  14. Computer model for electrochemical cell performance loss over time in terms of capacity, power, and conductance (CPC)

    Energy Science and Technology Software Center (OSTI)

    2015-09-01

    Available capacity, power, and cell conductance figure centrally into performance characterization of electrochemical cells (such as Li-ion cells) over their service life. For example, capacity loss in Li-ion cells is due to a combination of mechanisms, including loss of free available lithium, loss of active host sites, shifts in the potential-capacity curve, etc. Further distinctions can be made regarding irreversible and reversible capacity loss mechanisms. There are tandem needs for accurate interpretation of capacity atmore » characterization conditions (cycling rate, temperature, etc.) and for robust self-consistent modeling techniques that can be used for diagnostic analysis of cell data as well as forecasting of future performance. Analogous issues exist for aging effects on cell conductance and available power. To address these needs, a modeling capability was developed that provides a systematic analysis of the contributing factors to battery performance loss over aging and to act as a regression/prediction platform for cell performance. The modeling basis is a summation of self-consistent chemical kinetics rate expressions, which as individual expressions each covers a distinct mechanism (e.g., loss of active host sites, lithium loss), but collectively account for the net loss of premier metrics (e.g., capacity) over time for a particular characterization condition. Specifically, sigmoid-based rate expressions are utilized to describe each contribution to performance loss. Through additional mathematical development another tier of expressions is derived and used to perform differential analyses and segregate irreversible versus reversible contributions, as well as to determine concentration profiles over cell aging for affected Li+ ion inventory and fraction of active sites that remain at each time step. Reversible fade components are surmised by comparing fade rates at fast versus slow cycling conditions. The model is easily utilized for predictive

  15. Real-time characterization of partially observed epidemics using surrogate models.

    SciTech Connect (OSTI)

    Safta, Cosmin; Ray, Jaideep; Lefantzi, Sophia; Crary, David; Sargsyan, Khachik; Cheng, Karen

    2011-09-01

    We present a statistical method, predicated on the use of surrogate models, for the 'real-time' characterization of partially observed epidemics. Observations consist of counts of symptomatic patients, diagnosed with the disease, that may be available in the early epoch of an ongoing outbreak. Characterization, in this context, refers to estimation of epidemiological parameters that can be used to provide short-term forecasts of the ongoing epidemic, as well as to provide gross information on the dynamics of the etiologic agent in the affected population e.g., the time-dependent infection rate. The characterization problem is formulated as a Bayesian inverse problem, and epidemiological parameters are estimated as distributions using a Markov chain Monte Carlo (MCMC) method, thus quantifying the uncertainty in the estimates. In some cases, the inverse problem can be computationally expensive, primarily due to the epidemic simulator used inside the inversion algorithm. We present a method, based on replacing the epidemiological model with computationally inexpensive surrogates, that can reduce the computational time to minutes, without a significant loss of accuracy. The surrogates are created by projecting the output of an epidemiological model on a set of polynomial chaos bases; thereafter, computations involving the surrogate model reduce to evaluations of a polynomial. We find that the epidemic characterizations obtained with the surrogate models is very close to that obtained with the original model. We also find that the number of projections required to construct a surrogate model is O(10)-O(10{sup 2}) less than the number of samples required by the MCMC to construct a stationary posterior distribution; thus, depending upon the epidemiological models in question, it may be possible to omit the offline creation and caching of surrogate models, prior to their use in an inverse problem. The technique is demonstrated on synthetic data as well as observations from

  16. SRTC Participation in the Real-Time Modeling Intercomparison (RTMOD) Program

    SciTech Connect (OSTI)

    Griggs, D.P.

    1999-07-29

    'The Savannah River Technology Center of the U.S. Department of Energy''s Savannah River Site participated in the European Commission''s Real-Time Modeling Intercomparison (RTMOD) program. RTMOD comprised four exercises on the modeling of atmospheric transport and dispersion of hypothetical pollutant releases plus an intercomparison of the various model results for each exercise. SRTC participated in all four RTMOD exercises. This paper discusses the results obtained for the first exercise, a hypothetical release form Chernobyl in the Ukraine.'

  17. Evolution of a voltage-time model of thermal batteries. Technical memo

    SciTech Connect (OSTI)

    Knight, J.

    1991-02-01

    A temperature time model of thermal batteries has almost been completed and validated against experimental data. This Memorandum first summarises early attempts to integrate a voltage-time model into this, taking advantage of the instantaneous predictions of temperature, thermodynamic potentials, and internal resistance which the thermal model provides. It then describes how recent refinements of the voltage-time model have led to improved simulation of the discharges of a wide range of sizes and types of thermal battery under an equally wide range of test conditions. The semi-empirical approach adopted has been to provide a universally-applicable framework based on logical concepts to cover various effects such as polarisation etc, but with adjustable numerical parameters. It is shown that a moderately good simulation may be obtained for the majority of available discharge curves, using this one set of equations and without altering parameter values. Further improvements can be obtained when parameter values are optimised for one particular type of battery. Comparisons of model simulations against a body of experimental data have pinpointed remaining discrepancies which will guide further refinement efforts.

  18. Evolution of titanium arc weldment macro and microstructures -- Modeling and real time mapping of phases

    SciTech Connect (OSTI)

    Yang, Z.; Elmer, J.W.; Wong, J.; Debroy, T.

    2000-04-01

    Macro and microstructural features in gas tungsten arc (GTA) welded titanium were modeled for the first time based on a combination of transport phenomena and phase transformation theory. A transient, three-dimensional, turbulent heat transfer and fluid flow model was developed to calculate the temperature and velocity fields, thermal cycles, and the shape and size of the fusion zone. The kinetics of the {alpha}{r_arrow}{beta} allotropic transformation during continuous heating and the corresponding ({alpha}+{beta})/{beta} phase boundary were calculated using a modified Johnson-Mehl-Avrami (JMA) equation and the calculated thermal cycles. The modeling results were compared with the real-time phase mapping data obtained using a unique spatially resolved X-ray diffraction technique with synchrotron radiation. The real-time evolution of grain structure within the entire weld heat-affected zone (HAZ) was modeled in three dimensions using a Monte Carlo technique. The following are the major findings. First, the rates of heat transfer and fluid flow in the titanium weld pool during gas tungsten arc welding (GTAW) are significantly enhanced by turbulence, and previous calculations of laminar fluid flow and heat transfer in arc-melted pools need to be re-examined. The fusion zone geometry, and the {alpha}/({alpha}+{beta})/{beta} phase boundaries in the HAZ could be satisfactorily predicted. Second, comparison of real-time {alpha}{r_arrow}{beta} transformation kinetics with the rates computed assuming various alternative reaction mechanisms indicates the transition was most likely controlled by the transport of Ti atoms across the {alpha}/{beta} interface. Third, comparison of the experimental data with the simulated results indicates the real-time evolution of the grain structure around the weld pool could be simulated by the Monte Carlo technique. Finally, the insight developed in this research could not have been achieved without concomitant modeling and experiments.

  19. Series Transmission Line Transformer

    DOE Patents [OSTI]

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  20. Modeling molecule-plasmon interactions using quantized radiation fields within time-dependent electronic structure theory

    SciTech Connect (OSTI)

    Nascimento, Daniel R.; DePrince, A. Eugene

    2015-12-07

    We present a combined cavity quantum electrodynamics/ab initio electronic structure approach for simulating plasmon-molecule interactions in the time domain. The simple Jaynes-Cummings-type model Hamiltonian typically utilized in such simulations is replaced with one in which the molecular component of the coupled system is treated in a fully ab initio way, resulting in a computationally efficient description of general plasmon-molecule interactions. Mutual polarization effects are easily incorporated within a standard ground-state Hartree-Fock computation, and time-dependent simulations carry the same formal computational scaling as real-time time-dependent Hartree-Fock theory. As a proof of principle, we apply this generalized method to the emergence of a Fano-like resonance in coupled molecule-plasmon systems; this feature is quite sensitive to the nanoparticle-molecule separation and the orientation of the molecule relative to the polarization of the external electric field.

  1. Time-dependent models for dark matter at the galactic center

    SciTech Connect (OSTI)

    Bertone, Gianfranco

    2005-11-15

    The prospects for indirect detection of dark matter at the galactic center with {gamma}-ray experiments like the space telescope GLAST, and air Cherenkov telescopes like HESS, CANGAROO, MAGIC and VERITAS depend sensitively on the mass profile within the inner parsec. We calculate the distribution of dark matter on subparsec scales by integrating the time-dependent Fokker-Planck equation, including the effects of self-annihilations, scattering of dark matter particles by stars, and capture in the supermassive black hole. We consider a variety of initial dark matter distributions, including models with very high densities ('spikes') near the black hole, and models with 'adiabatic compression' of the baryons. The annihilation signal after 10{sup 10} yr is found to be substantially reduced from its initial value, but in dark matter models with an initial spike, order-of-magnitude enhancements can persist compared with the rate in spike-free models.

  2. DOE Tribal Renewable Energy Webinar Series 2014 | Department of Energy

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

    Renewable Energy Webinar Series 2014 DOE Tribal Renewable Energy Webinar Series 2014 2014 webinar series flyer (619.61 KB) More Documents & Publications The Path to Transforming Knowledge into Energy Projects: DOE Tribal Renewable Energy Webinar Series 2015 2016 Tribal Energy and Economic Development July Webinar: Project Development for Long-Term Tribal Energy System Advisor Model Training

  3. How real-time cosmology can distinguish between different anisotropic models

    SciTech Connect (OSTI)

    Amendola, Luca; Bjlde, Ole Eggers; Valkenburg, Wessel; Wong, Yvonne Y.Y. E-mail: oeb@phys.au.dk E-mail: yvonne.y.wong@unsw.edu.au

    2013-12-01

    We present a new analysis on how to distinguish between isotropic and anisotropic cosmological models based on tracking the angular displacements of a large number of distant quasars over an extended period of time, and then performing a multipole-vector decomposition of the resulting displacement maps. We find that while the GAIA mission operating at its nominal specifications does not have sufficient angular resolution to resolve anisotropic universes from isotropic ones using this method within a reasonable timespan of ten years, a next-generation GAIA-like survey with a resolution ten times better should be equal to the task. Distinguishing between different anisotropic models is however more demanding. Keeping the observational timespan to ten years, we find that the angular resolution of the survey will need to be of order 0.1 ?as in order for certain rotating anisotropic models to produce a detectable signature that is also unique to models of this class. However, should such a detection become possible, it would immediately allow us to rule out large local void models.

  4. Time-dependent finite-element models of phase-change problems with moving heat sources

    SciTech Connect (OSTI)

    Westerberg, K.W. ); Wiklof, C. ); Finlayson, B.A. . Dept. of Chemical Engineering)

    1994-03-01

    A mathematical model is developed for melting of a multilayered medium while a heat source traverses one boundary. The finite-element method uses moving meshes, front-tracking using spines, an automatic time-step algorithm, and an efficient solution of the linearized equations. A novel solution method allows the fixed-mesh code to work unchanged but allows a moving mesh in other problems. The finite-element method is applied when the heater mesh moves with respect to the multilayered medium mesh. The same technique allows parallel processing for finite-element codes. The model is applied to several test problems and then to the title problem.

  5. Semiclassical matrix model for quantum chaotic transport with time-reversal symmetry

    SciTech Connect (OSTI)

    Novaes, Marcel

    2015-10-15

    We show that the semiclassical approach to chaotic quantum transport in the presence of time-reversal symmetry can be described by a matrix model. In other words, we construct a matrix integral whose perturbative expansion satisfies the semiclassical diagrammatic rules for the calculation of transport statistics. One of the virtues of this approach is that it leads very naturally to the semiclassical derivation of universal predictions from random matrix theory.

  6. WAITING TIME DISTRIBUTION OF SOLAR ENERGETIC PARTICLE EVENTS MODELED WITH A NON-STATIONARY POISSON PROCESS

    SciTech Connect (OSTI)

    Li, C.; Su, W.; Fang, C.; Zhong, S. J.; Wang, L.

    2014-09-10

    We present a study of the waiting time distributions (WTDs) of solar energetic particle (SEP) events observed with the spacecraft WIND and GOES. The WTDs of both solar electron events (SEEs) and solar proton events (SPEs) display a power-law tail of ∼Δt {sup –γ}. The SEEs display a broken power-law WTD. The power-law index is γ{sub 1} = 0.99 for the short waiting times (<70 hr) and γ{sub 2} = 1.92 for large waiting times (>100 hr). The break of the WTD of SEEs is probably due to the modulation of the corotating interaction regions. The power-law index, γ ∼ 1.82, is derived for the WTD of the SPEs which is consistent with the WTD of type II radio bursts, indicating a close relationship between the shock wave and the production of energetic protons. The WTDs of SEP events can be modeled with a non-stationary Poisson process, which was proposed to understand the waiting time statistics of solar flares. We generalize the method and find that, if the SEP event rate λ = 1/Δt varies as the time distribution of event rate f(λ) = Aλ{sup –α}exp (– βλ), the time-dependent Poisson distribution can produce a power-law tail WTD of ∼Δt {sup α} {sup –3}, where 0 ≤ α < 2.

  7. Testing the (generalized) Chaplygin gas model with the lookback time-redshift data

    SciTech Connect (OSTI)

    Li, Zhengxiang; Wu, Puxun; Yu, Hongwei E-mail: wpx0227@gmail.com

    2009-09-01

    The Chaplygin gas (CG) and the generalized Chaplygin gas (GCG) models, proposed as candidates of the unified dark matter-dark energy (UDME), are tested with the look-back time (LT) redshift data. We find that the LT data only give a very weak constraint on the model parameter. However, by combing the LT with the baryonic acoustic oscillation peak, we obtain, at the 95.4% confidence level, 0.68 ≤ A{sub c} ≤ 0.82 and 0.59 ≤ h ≤ 0.65 for the CG model , and 0.67 ≤ A{sub s} ≤ 0.89 and −0.29 ≤ α ≤ 0.61 for the GCG model. This shows that both the CG and the GCG are viable as a candidate of UDME. Within the GCG model, we also find that the Chaplygin gas model (α = 1) is ruled out by these data at the 99.7% confidence level.

  8. Model-independent plotting of the cosmological scale factor as a function of lookback time

    SciTech Connect (OSTI)

    Ringermacher, H. I.; Mead, L. R., E-mail: ringerha@gmail.com, E-mail: Lawrence.mead@usm.edu [Department of Physics and Astronomy, University of Southern Mississippi, Hattiesburg, MS 39406 (United States)

    2014-11-01

    In this work we describe a model-independent method of developing a plot of scale factor a(t) versus lookback time t{sub L} from the usual Hubble diagram of modulus data against redshift. This is the first plot of this type. We follow the model-independent methodology of Daly and Djorgovski used for their radio-galaxy data. Once the a(t)data plot is completed, any model can be applied and will display as described in the standard literature. We then compile an extensive data set to z = 1.8 by combining Type Ia supernovae (SNe Ia) data from SNLS3 of Conley et al., high-z SNe data of Riess et al., and radio-galaxy data of Daly and Djorgovski to validate the new plot. We first display these data on a standard Hubble diagram to confirm the best fit for ?CDM cosmology, and thus validate the joined data set. The scale factor plot is then developed from the data and the ?CDM model is again displayed from a least-squares fit. The fit parameters are in agreement with the Hubble diagram fit confirming the validity of the new plot. Of special interest is the transition time of the universe, which in the scale factor plot will appear as an inflection point in the data set. Noise is more visible in this presentation, which is particularly sensitive to inflection points of any model displayed in the plot, unlike on a modulus-z diagram, where there are no inflection points and the transition-z is not at all obvious by inspection. We obtain a lower limit of z ? 0.6. It is evident from this presentation that there is a dearth of SNe data in the range z = 1-2, exactly the range necessary to confirm a ?CDM transition-z around z = 0.76. We then compare a 'toy model' wherein dark matter is represented as a perfect fluid with an equation of state p = (1/3) ? to demonstrate the plot sensitivity to model choice. Its density varies as 1/t {sup 2} and it enters the Friedmann equations as ?{sub dark}/t {sup 2}, replacing only the ?{sub dark}/a {sup 3} term. The toy model is a close match to

  9. Modeling laser-induced periodic surface structures: Finite-difference time-domain feedback simulations

    SciTech Connect (OSTI)

    Skolski, J. Z. P. Vincenc Obona, J.; Römer, G. R. B. E.; Huis in 't Veld, A. J.

    2014-03-14

    A model predicting the formation of laser-induced periodic surface structures (LIPSSs) is presented. That is, the finite-difference time domain method is used to study the interaction of electromagnetic fields with rough surfaces. In this approach, the rough surface is modified by “ablation after each laser pulse,” according to the absorbed energy profile, in order to account for inter-pulse feedback mechanisms. LIPSSs with a periodicity significantly smaller than the laser wavelength are found to “grow” either parallel or orthogonal to the laser polarization. The change in orientation and periodicity follow from the model. LIPSSs with a periodicity larger than the wavelength of the laser radiation and complex superimposed LIPSS patterns are also predicted by the model.

  10. Test Cases for Wind Power Plant Dynamic Models on Real-Time Digital Simulator: Preprint

    SciTech Connect (OSTI)

    Singh, M.; Muljadi, E.; Gevorgian, V.

    2012-06-01

    The objective of this paper is to present test cases for wind turbine generator and wind power plant models commonly used during commissioning of wind power plants to ensure grid integration compatibility. In this paper, different types of wind power plant models based on the Western Electricity Coordinating Council Wind Generator Modeling Group's standardization efforts are implemented on a real-time digital simulator, and different test cases are used to gauge their grid integration capability. The low-voltage ride through and reactive power support capability and limitations of wind turbine generators under different grid conditions are explored. Several types of transient events (e.g., symmetrical and unsymmetrical faults, frequency dips) are included in the test cases. The differences in responses from different types of wind turbine are discussed in detail.

  11. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    SciTech Connect (OSTI)

    Yin, Youbing, E-mail: youbing-yin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States) [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Choi, Jiwoong, E-mail: jiwoong-choi@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States) [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Hoffman, Eric A., E-mail: eric-hoffman@uiowa.edu [Department of Radiology, The University of Iowa, Iowa City, IA 52242 (United States); Department of Biomedical Engineering, The University of Iowa, Iowa City, IA 52242 (United States); Department of Internal Medicine, The University of Iowa, Iowa City, IA 52242 (United States); Tawhai, Merryn H., E-mail: m.tawhai@auckland.ac.nz [Auckland Bioengineering Institute, The University of Auckland, Auckland (New Zealand); Lin, Ching-Long, E-mail: ching-long-lin@uiowa.edu [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States) [Department of Mechanical and Industrial Engineering, The University of Iowa, Iowa City, IA 52242 (United States); IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City, IA 52242 (United States)

    2013-07-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

  12. Photon and neutrino spectra of time-dependent photospheric models of gamma-ray bursts

    SciTech Connect (OSTI)

    Asano, K. [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Mszros, P., E-mail: asanok@icrr.u-tokyo.ac.jp, E-mail: nnp@astro.psu.edu [Department of Astronomy and Astrophysics, Department of Physics, Center for Particle and Gravitational Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

    2013-09-01

    Thermal photons from the photosphere may be the primary source of the observed prompt emission of gamma-ray bursts (GRBs). In order to produce the observed non-thermal spectra, some kind of dissipation mechanism near the photosphere is required. In this paper we numerically simulate the evolution of the photon spectrum in a relativistically expanding shell with a time-dependent numerical code. We consider two basic models. One is a leptonic model, where a dissipation mechanism heats the thermal electrons maintaining their high temperature. The other model involves a cascade process induced by pp(pn)-collisions which produce high-energy electrons, modify the thermal spectrum, and emit neutrinos. The qualitative properties of the photon spectra are mainly determined by the optical depth at which the dissipation mechanism sets in. Too large optical depths lead to a broad and curved spectrum contradicting the observations, while for optical depths smaller than unity the spectral hardness becomes softer than observed. A significant shift of the spectral peak energy to higher energies due to a large energy injection can lead to an overly broad spectral shape. We show ideal parameter ranges for which these models are able to reproduce the observed spectra. For the pn-collision model, the neutrino fluence in the 10100 GeV range is well above the atmospheric neutrino fluence, but its detection is challenging for presently available detectors.

  13. Model based approach to UXO imaging using the time domain electromagnetic method

    SciTech Connect (OSTI)

    Lavely, E.M.

    1999-04-01

    Time domain electromagnetic (TDEM) sensors have emerged as a field-worthy technology for UXO detection in a variety of geological and environmental settings. This success has been achieved with commercial equipment that was not optimized for UXO detection and discrimination. The TDEM response displays a rich spatial and temporal behavior which is not currently utilized. Therefore, in this paper the author describes a research program for enhancing the effectiveness of the TDEM method for UXO detection and imaging. Fundamental research is required in at least three major areas: (a) model based imaging capability i.e. the forward and inverse problem, (b) detector modeling and instrument design, and (c) target recognition and discrimination algorithms. These research problems are coupled and demand a unified treatment. For example: (1) the inverse solution depends on solution of the forward problem and knowledge of the instrument response; (2) instrument design with improved diagnostic power requires forward and inverse modeling capability; and (3) improved target recognition algorithms (such as neural nets) must be trained with data collected from the new instrument and with synthetic data computed using the forward model. Further, the design of the appropriate input and output layers of the net will be informed by the results of the forward and inverse modeling. A more fully developed model of the TDEM response would enable the joint inversion of data collected from multiple sensors (e.g., TDEM sensors and magnetometers). Finally, the author suggests that a complementary approach to joint inversions is the statistical recombination of data using principal component analysis. The decomposition into principal components is useful since the first principal component contains those features that are most strongly correlated from image to image.

  14. Exact calculation of the time convolutionless master equation generator: Application to the nonequilibrium resonant level model

    SciTech Connect (OSTI)

    Kidon, Lyran; Wilner, Eli Y.; Rabani, Eran

    2015-12-21

    The generalized quantum master equation provides a powerful tool to describe the dynamics in quantum impurity models driven away from equilibrium. Two complementary approaches, one based on Nakajima–Zwanzig–Mori time-convolution (TC) and the other on the Tokuyama–Mori time-convolutionless (TCL) formulations provide a starting point to describe the time-evolution of the reduced density matrix. A key in both approaches is to obtain the so called “memory kernel” or “generator,” going beyond second or fourth order perturbation techniques. While numerically converged techniques are available for the TC memory kernel, the canonical approach to obtain the TCL generator is based on inverting a super-operator in the full Hilbert space, which is difficult to perform and thus, nearly all applications of the TCL approach rely on a perturbative scheme of some sort. Here, the TCL generator is expressed using a reduced system propagator which can be obtained from system observables alone and requires the calculation of super-operators and their inverse in the reduced Hilbert space rather than the full one. This makes the formulation amenable to quantum impurity solvers or to diagrammatic techniques, such as the nonequilibrium Green’s function. We implement the TCL approach for the resonant level model driven away from equilibrium and compare the time scales for the decay of the generator with that of the memory kernel in the TC approach. Furthermore, the effects of temperature, source-drain bias, and gate potential on the TCL/TC generators are discussed.

  15. TIME-LAPSE SEISMIC MODELING & INVERSION OF CO2 SATURATION FOR SEQUESTRATION AND ENHANCED OIL RECOVERY

    SciTech Connect (OSTI)

    Mark A. Meadows

    2006-03-31

    Injection of carbon dioxide (CO2) into subsurface aquifers for geologic storage/sequestration, and into subsurface hydrocarbon reservoirs for enhanced oil recovery, has become an important topic to the nation because of growing concerns related to global warming and energy security. In this project we developed new ways to predict and quantify the effects of CO2 on seismic data recorded over porous reservoir/aquifer rock systems. This effort involved the research and development of new technology to: (1) Quantitatively model the rock physics effects of CO2 injection in porous saline and oil/brine reservoirs (both miscible and immiscible). (2) Quantitatively model the seismic response to CO2 injection (both miscible and immiscible) from well logs (1D). (3) Perform quantitative inversions of time-lapse 4D seismic data to estimate injected CO2 distributions within subsurface reservoirs and aquifers. This work has resulted in an improved ability to remotely monitor the injected CO2 for safe storage and enhanced hydrocarbon recovery, predict the effects of CO2 on time-lapse seismic data, and estimate injected CO2 saturation distributions in subsurface aquifers/reservoirs. We applied our inversion methodology to a 3D time-lapse seismic dataset from the Sleipner CO2 sequestration project, Norwegian North Sea. We measured changes in the seismic amplitude and traveltime at the top of the Sleipner sandstone reservoir and used these time-lapse seismic attributes in the inversion. Maps of CO2 thickness and its standard deviation were generated for the topmost layer. From this information, we estimated that 7.4% of the total CO2 injected over a five-year period had reached the top of the reservoir. This inversion approach could also be applied to the remaining levels within the anomalous zone to obtain an estimate of the total CO2 injected.

  16. The East Asia geographic map series

    SciTech Connect (OSTI)

    Terman, M.J.; Bell, E.P. )

    1990-06-01

    During the last 15 years, the Circum-Pacific Map Project Northwest Quadrant Panel (NWQP) has created a map inventory of geoscience data at a scale of 1:10,000,000. Now, for East Asia, a second set of thematic maps is being initiated cooperatively by the Circum-Pacific Council for Energy and Mineral Resources and the Committee for Coordination of Joint Prospecting for Mineral Resources in Asian Offshore Areas (CCOP). These new maps will constitute the East Asia Map Project, and they will present geoscience parameters at a scale of 1:2,000,000 that can be used to evaluate the potential for undiscovered resources with the application of new deposit modeling methodologies. The following map series are being compiled or are under consideration: geography, geotectonics, geophysics, mineral resources, energy resources, and hazards. The U.S, Geological Survey (USGS) is compiling the East Asia Geographic Map Series. Shorelines, rivers, and international boundaries have been computer plotted by the National Mapping Division from the most detailed version of the World Data Bank II (WDB II). This publicly available bank was hand digitized from a 1:3,000,000-scale global map compiled from a variety of sources. The East Asia series is composed of eight overlapping sheets with Lambert Azimuthal Equal-Area Projection having a common point of origin at 120{degree}E and 15{degree}N; neatlines for each sheet are 39{degree} {times} 54.4{degree}. Titles reflect each map's coverage: Sheet 1, Japan/Korea/Northeast China; Sheet 2, Southeast China; Sheet 3, Southeast Asia; Sheet 4, Philippines; Sheet 5, Malaysia/ West Indonesia; Sheet 6, East Indonesia; Sheet 7, Papua New Guinea/ Solomon Islands; and Sheet 8, Western Pacific Islands. Contours have been scribed by the USGS's Office of International Geology.

  17. Multi-fluid transport code modeling of time-dependent recycling in ELMy H-mode

    SciTech Connect (OSTI)

    Pigarov, A. Yu.; Krasheninnikov, S. I.; Hollmann, E. M.; Rognlien, T. D.; Lasnier, C. J.; Unterberg, E.

    2014-06-15

    Simulations of a high-confinement-mode (H-mode) tokamak discharge with infrequent giant type-I ELMs are performed by the multi-fluid, multi-species, two-dimensional transport code UEDGE-MB, which incorporates the Macro-Blob approach for intermittent non-diffusive transport due to filamentary coherent structures observed during the Edge Localized Modes (ELMs) and simple time-dependent multi-parametric models for cross-field plasma transport coefficients and working gas inventory in material surfaces. Temporal evolutions of pedestal plasma profiles, divertor recycling, and wall inventory in a sequence of ELMs are studied and compared to the experimental time-dependent data. Short- and long-time-scale variations of the pedestal and divertor plasmas where the ELM is described as a sequence of macro-blobs are discussed. It is shown that the ELM recovery includes the phase of relatively dense and cold post-ELM divertor plasma evolving on a several ms scale, which is set by the transport properties of H-mode barrier. The global gas balance in the discharge is also analyzed. The calculated rates of working gas deposition during each ELM and wall outgassing between ELMs are compared to the ELM particle losses from the pedestal and neutral-beam-injection fueling rate, correspondingly. A sensitivity study of the pedestal and divertor plasmas to model assumptions for gas deposition and release on material surfaces is presented. The performed simulations show that the dynamics of pedestal particle inventory is dominated by the transient intense gas deposition into the wall during each ELM followed by continuous gas release between ELMs at roughly a constant rate.

  18. Multi-fluid transport code modeling of time-dependent recycling in ELMy H-mode

    SciTech Connect (OSTI)

    Pigarov, A. Yu.; Krasheninnikov, S. I.; Rognlien, T. D.; Hollmann, E. M.; Lasnier, C. J.; Unterberg, Ezekial A

    2014-01-01

    Simulations of a high-confinement-mode (H-mode) tokamak discharge with infrequent giant type-I ELMs are performed by the multi-fluid, multi-species, two-dimensional transport code UEDGE-MB, which incorporates the Macro-Blob approach for intermittent non-diffusive transport due to filamentary coherent structures observed during the Edge Localized Modes (ELMs) and simple time-dependent multi-parametric models for cross-field plasma transport coefficients and working gas inventory in material surfaces. Temporal evolutions of pedestal plasma profiles, divertor recycling, and wall inventory in a sequence of ELMs are studied and compared to the experimental time-dependent data. Short- and long-time-scale variations of the pedestal and divertor plasmas where the ELM is described as a sequence of macro-blobs are discussed. It is shown that the ELM recovery includes the phase of relatively dense and cold post-ELM divertor plasma evolving on a several ms scale, which is set by the transport properties of H-mode barrier. The global gas balance in the discharge is also analyzed. The calculated rates of working gas deposition during each ELM and wall outgassing between ELMs are compared to the ELM particle losses from the pedestal and neutral-beam-injection fueling rate, correspondingly. A sensitivity study of the pedestal and divertor plasmas to model assumptions for gas deposition and release on material surfaces is presented. The performed simulations show that the dynamics of pedestal particle inventory is dominated by the transient intense gas deposition into the wall during each ELM followed by continuous gas release between ELMs at roughly a constant rate.

  19. Time-dependent models for blazar emission with the second-order Fermi acceleration

    SciTech Connect (OSTI)

    Asano, Katsuaki; Takahara, Fumio; Toma, Kenji; Kusunose, Masaaki; Kakuwa, Jun

    2014-01-01

    The second-order Fermi acceleration (Fermi-II) driven by turbulence may be responsible for the electron acceleration in blazar jets. We test this model with time-dependent simulations. The hard electron spectrum predicted by the Fermi-II process agrees with the hard photon spectrum of 1ES 1101–232. For other blazars that show softer spectra, the Fermi-II model requires radial evolution of the electron injection rate and/or diffusion coefficient in the outflow. Such evolutions can yield a curved electron spectrum, which can reproduce the synchrotron spectrum of Mrk 421 from the radio to the X-ray regime. The photon spectrum in the GeV energy range of Mrk 421 is hard to fit with a synchrotron self-Compton model. However, if we introduce an external radio photon field with a luminosity of 4.9 × 10{sup 38} erg s{sup –1}, GeV photons are successfully produced via inverse Compton scattering. The temporal variability of the diffusion coefficient or injection rate causes flare emission. The observed synchronicity of X-ray and TeV flares implies a decrease of the magnetic field in the flaring source region.

  20. Modeling a Typical Winter-time Dust Event over the Arabian Peninsula and the Red Sea

    SciTech Connect (OSTI)

    Kalenderski, S.; Stenchikov, G.; Zhao, Chun

    2013-02-20

    We used WRF-Chem, a regional meteorological model coupled with an aerosol-chemistry component, to simulate various aspects of the dust phenomena over the Arabian Peninsula and Red Sea during a typical winter-time dust event that occurred in January 2009. The model predicted that the total amount of emitted dust was 18.3 Tg for the entire dust outburst period and that the two maximum daily rates were ~2.4 Tg/day and ~1.5 Tg/day, corresponding to two periods with the highest aerosol optical depth that were well captured by ground- and satellite-based observations. The model predicted that the dust plume was thick, extensive, and mixed in a deep boundary layer at an altitude of 3-4 km. Its spatial distribution was modeled to be consistent with typical spatial patterns of dust emissions. We utilized MODIS-Aqua and Solar Village AERONET measurements of the aerosol optical depth (AOD) to evaluate the radiative impact of aerosols. Our results clearly indicated that the presence of dust particles in the atmosphere caused a significant reduction in the amount of solar radiation reaching the surface during the dust event. We also found that dust aerosols have significant impact on the energy and nutrient balances of the Red Sea. Our results showed that the simulated cooling under the dust plume reached 100 W/m2, which could have profound effects on both the sea surface temperature and circulation. Further analysis of dust generation and its spatial and temporal variability is extremely important for future projections and for better understanding of the climate and ecological history of the Red Sea.

  1. Energy Management Webinar Series

    Broader source: Energy.gov [DOE]

    Boost your knowledge on how to implement an energy management system through this four-part webinar series from the Superior Energy Performance program. Each webinar introduces various elements of the ISO 50001 energy management standard—based on the Plan-Do-Check-Act approach—and the associated steps of DOE's eGuide for ISO 50001 software tool.

  2. Nobel Keynote Lecture Series at Berkeley Lab

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

    Nobel Keynote Lecture Series Nobel Keynote Lecture Series at Berkeley Lab June 4, 2014 27415NERSC 40 YR MarkFinal In honor of its 40th Anniversary, NERSC is sponsoring a series of lectures describing the research behind four Nobel Prizes. The Laureates are also long-time users of NERSC's supercomputing resources. All talks will be held at Berkeley Lab in Bldg. 66, except for Saul Perlmutter (June 11), which will take place in Bldg. 50. Each talk begins at noon and runs to 1:30. UC Berkeley staff

  3. Seminar Series | Photosynthetic Antenna Research Center

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

    Seminar Series Seminar Series Dr. Tristram Kidder Ancient Lessons for Modern Times: An Environmental History of the Yellow River, China, 5000-2000 BC Donald Ort Too Green? Dr. Terry Bricker Structural Interactions of the Extrinsic Proteins in Higher Plant Photosystem II Dr. David Tiede "Wiring Photosynthetic and Redox Proteins for Solar Fuels Function" Dr. Su Lin "Electron Transfer Kinetics in Bacterial Reaction Center" Dr. Donald Bryant "Far-red light photoacclimation

  4. Nobel Keynote Lecture Series May 20 - June 11

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

    Keynote Lecture Series May 20 - June 11 Nobel Keynote Lecture Series May 20 - June 11 May 5, 2014 by Francesca Verdier In honor of its 40th Anniversary, NERSC is sponsoring a series of lectures describing the research behind four Nobel Prizes. The Laureates are also long-time users of NERSC's supercomputing resources. See: NERSC Sponsors Lunchtime Nobel Keynote Lecture Series at Berkeley Lab. These lectures will be live streamed; to watch follow this link: hosting.epresence.tv/lbl. Subscribe via

  5. 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

    2015-02-09

    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 μg kg−1air, compared with measurements of 1.0–1.5 μg 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

  6. Incorporating a Time Horizon in Rate-of-Return Estimations: Discounted Cash Flow Model in Electric Transmission Rate Cases

    SciTech Connect (OSTI)

    Chatterjee, Bishu; Sharp, Peter A.

    2006-07-15

    Electric transmission and other rate cases use a form of the discounted cash flow model with a single long-term growth rate to estimate rates of return on equity. It cannot incorporate information about the appropriate time horizon for which analysts' estimates of earnings growth have predictive powers. Only a non-constant growth model can explicitly recognize the importance of the time horizon in an ROE calculation. (author)

  7. Modelling and real-time simulation of continuous-discrete systems in mechatronics

    SciTech Connect (OSTI)

    Lindow, H.

    1996-12-31

    This work presents a methodology for simulation and modelling of systems with continuous - discrete dynamics. It derives hybrid discrete event models from Lagrange`s equations of motion. This method combines continuous mechanical, electrical and thermodynamical submodels on one hand with discrete event models an the other hand into a hybrid discrete event model. This straight forward software development avoids numeric overhead.

  8. OPG Leadership Series Kickoff,

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

    OPG Leadership Series Kickoff, September, 2005 ZFS THE LAST WORD IN FILE SYSTEMS ¢ ¡ £ ¤ ¥¦ § ¨  ©  ¢     ¡ £  ¨ §¡    § ¦  ¡  ¢    ¨  £  ! © § ¦ §" #  % $ © &  ¢  ¡ §  #  ¨ £'   ( ©   ) ZFS - The Last Word in Filesystems ZFS - The Last Word in File Systems ZFS Overview ¡ £ ¢ ¤¥ ¦ §¨ ©  ¦  ¦  £ 

  9. Soils Soil Series

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

    Soils Soil Series and Phase DBaC i:JFu IIiiiiIO!:l _PK _TuE _Ud DVeD o o o 1180 Meters o 590 \' Community _ Loblolly Pine D Mixed Pine/Hardwood D Upland Hardwood D Bonomland Hardwood iiiI Bonomland HardwoodlPine N Streams * TES Plants (1) D TES Plants (2) U Monitoring Wells o SRS Bays 6 ~ Utili1y ROW !.! Openwells tit NPDES outfalls ** Areas WI Roads rnOther Set-Asides ~ Hydric Soils Figure 15-1. Plant cOllllllunities and soils associated with the WhippldOH ER Study Site Set-Aside Area. 15-7

  10. Soils Soil Series

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

    0 Soils Soil Series and Phase D Fa D LaB _ TrB D TrC _ VeC .Wm '" Vegetation Compartment 28 Community D Mixed Pine/Hardwood D Upland Hardwod D Bottomland Hardwood _Water D Sandhill Scrub oak/Pine D Sandhill Pine/Scrub oak N Streams Roads _Water [2LJ Other Set-Asides DTES Plants (2) llilliJ Hydric Soils Road 8.11 560 Meters Figure 29-1. Plant cOllll1lunities and soils associated with the Scrub Oak Natural Area. 29-5 Set-Aside 29: Scrub Oak Natural Area

  11. Frontiers in Science Lecture Series

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

    Video Resources » Frontiers in Science Lecture Series Frontiers in Science Lecture Series The Laboratory Fellows are appointed by the Laboratory Director in recognition of sustained outstanding contributions and exceptional promise for continued professional achievement. The Frontiers in Science series shares the Laboratory's cutting-edge research with the surrounding community. Contact Communications Office (505)665-9196 or (505)667-7000 Frontiers in Science Lecture Series Presented by the Los

  12. Lattice and off-lattice side chain models of protein folding: Linear time structure prediction better than 86% of optimal

    SciTech Connect (OSTI)

    Hart, W.E.; Istrail, S. [Sandia National Labs., Albuquerque, NM (United States). Algorithms and Discrete Mathematics Dept.

    1996-08-09

    This paper considers the protein structure prediction problem for lattice and off-lattice protein folding models that explicitly represent side chains. Lattice models of proteins have proven extremely useful tools for reasoning about protein folding in unrestricted continuous space through analogy. This paper provides the first illustration of how rigorous algorithmic analyses of lattice models can lead to rigorous algorithmic analyses of off-lattice models. The authors consider two side chain models: a lattice model that generalizes the HP model (Dill 85) to explicitly represent side chains on the cubic lattice, and a new off-lattice model, the HP Tangent Spheres Side Chain model (HP-TSSC), that generalizes this model further by representing the backbone and side chains of proteins with tangent spheres. They describe algorithms for both of these models with mathematically guaranteed error bounds. In particular, the authors describe a linear time performance guaranteed approximation algorithm for the HP side chain model that constructs conformations whose energy is better than 865 of optimal in a face centered cubic lattice, and they demonstrate how this provides a 70% performance guarantee for the HP-TSSC model. This is the first algorithm in the literature for off-lattice protein structure prediction that has a rigorous performance guarantee. The analysis of the HP-TSSC model builds off of the work of Dancik and Hannenhalli who have developed a 16/30 approximation algorithm for the HP model on the hexagonal close packed lattice. Further, the analysis provides a mathematical methodology for transferring performance guarantees on lattices to off-lattice models. These results partially answer the open question of Karplus et al. concerning the complexity of protein folding models that include side chains.

  13. CLEAR (Calculates Logical Evacuation And Response): A Generic Transportation Network Model for the Calculation of Evacuation Time Estimates

    SciTech Connect (OSTI)

    Moeller, M. P.; Urbanik, II, T.; Desrosiers, A. E.

    1982-03-01

    This paper describes the methodology and application of the computer model CLEAR (Calculates Logical Evacuation And Response) which estimates the time required for a specific population density and distribution to evacuate an area using a specific transportation network. The CLEAR model simulates vehicle departure and movement on a transportation network according to the conditions and consequences of traffic flow. These include handling vehicles at intersecting road segments, calculating the velocity of travel on a road segment as a function of its vehicle density, and accounting for the delay of vehicles in traffic queues. The program also models the distribution of times required by individuals to prepare for an evacuation. In order to test its accuracy, the CLEAR model was used to estimate evacuatlon tlmes for the emergency planning zone surrounding the Beaver Valley Nuclear Power Plant. The Beaver Valley site was selected because evacuation time estimates had previously been prepared by the licensee, Duquesne Light, as well as by the Federal Emergency Management Agency and the Pennsylvania Emergency Management Agency. A lack of documentation prevented a detailed comparison of the estimates based on the CLEAR model and those obtained by Duquesne Light. However, the CLEAR model results compared favorably with the estimates prepared by the other two agencies.

  14. Department of Energy to Provide Supercomputing Time to Run NOAA's Climate Change Models

    Broader source: Energy.gov [DOE]

    WASHINGTON, DC -   The U.S. Department of Energy's (DOE) Office of Science will make available more than 10 million hours of computing time for the U.S. Commerce Department's  National Oceanic and...

  15. Real-time global flood estimation using satellite-based precipitation and a coupled land surface and routing model

    SciTech Connect (OSTI)

    Wu, Huan; Adler, Robert F.; Tian, Yudong; Huffman, George J.; Li, Hongyi; Wang, JianJian

    2014-03-01

    A widely used land surface model, the Variable Infiltration Capacity (VIC) model, is coupled with a newly developed hierarchical dominant river tracing-based runoff-routing model to form the Dominant river tracing-Routing Integrated with VIC Environment (DRIVE) model, which serves as the new core of the real-time Global Flood Monitoring System (GFMS). The GFMS uses real-time satellite-based precipitation to derive flood monitoring parameters for the latitude band 50°N–50°S at relatively high spatial (~12 km) and temporal (3 hourly) resolution. Examples of model results for recent flood events are computed using the real-time GFMS (http://flood.umd.edu). To evaluate the accuracy of the new GFMS, the DRIVE model is run retrospectively for 15 years using both research-quality and real-time satellite precipitation products. Evaluation results are slightly better for the research-quality input and significantly better for longer duration events (3 day events versus 1 day events). Basins with fewer dams tend to provide lower false alarm ratios. For events longer than three days in areas with few dams, the probability of detection is ~0.9 and the false alarm ratio is ~0.6. In general, these statistical results are better than those of the previous system. Streamflow was evaluated at 1121 river gauges across the quasi-global domain. Validation using real-time precipitation across the tropics (30°S–30°N) gives positive daily Nash-Sutcliffe Coefficients for 107 out of 375 (28%) stations with a mean of 0.19 and 51% of the same gauges at monthly scale with a mean of 0.33. Finally, there were poorer results in higher latitudes, probably due to larger errors in the satellite precipitation input.

  16. Operating Innovative Networks Workshop Series

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

    Operating Innovative Networks Workshop Series Science Engagement Move your data Programs & Workshops CrossConnects Workshop Series Operating Innovative Networks Workshop Series Enlighten Your Research Global Program Science Requirements Reviews Case Studies Contact Us Technical Assistance: 1 800-33-ESnet (Inside US) 1 800-333-7638 (Inside US) 1 510-486-7600 (Globally) 1 510-486-7607 (Globally) Report Network Problems: trouble@es.net Provide Web Site Feedback: info@es.net Operating Innovative

  17. Intel Xeon Phi Webinar Series

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

    Webinar Series Intel Xeon Phi Webinar Series July 2, 2015 by Richard Gerber Intel, through a third-party trainer, is sponsoring a series of webinars focused on the Xeon Phi. You can register at https://attendee.gotowebinar.com/register/1855310790447082498 Schedule: Wed, July 1 - "Hello world from Intel Xeon Phi coprocessors". Overview of architecture, preview of course topics. Thur, July 2 - "Offload programming for Intel coprocessors". Introduction to offload programming.

  18. SU-E-J-115: Using Markov Chain Modeling to Elucidate Patterns in Breast Cancer Metastasis Over Time and Space

    SciTech Connect (OSTI)

    Comen, E; Mason, J; Kuhn, P; Nieva, J; Newton, P; Norton, L; Venkatappa, N; Jochelson, M

    2014-06-01

    Purpose: Traditionally, breast cancer metastasis is described as a process wherein cancer cells spread from the breast to multiple organ systems via hematogenous and lymphatic routes. Mapping organ specific patterns of cancer spread over time is essential to understanding metastatic progression. In order to better predict sites of metastases, here we demonstrate modeling of the patterned migration of metastasis. Methods: We reviewed the clinical history of 453 breast cancer patients from Memorial Sloan Kettering Cancer Center who were non-metastatic at diagnosis but developed metastasis over time. We used the variables of organ site of metastases as well as time to create a Markov chain model of metastasis. We illustrate the probabilities of metastasis occurring at a given anatomic site together with the probability of spread to additional sites. Results: Based on the clinical histories of 453 breast cancer patients who developed metastasis, we have learned (i) how to create the Markov transition matrix governing the probabilities of cancer progression from site to site; (ii) how to create a systemic network diagram governing disease progression modeled as a random walk on a directed graph; (iii) how to classify metastatic sites as sponges that tend to only receive cancer cells or spreaders that receive and release them; (iv) how to model the time-scales of disease progression as a Weibull probability distribution function; (v) how to perform Monte Carlo simulations of disease progression; and (vi) how to interpret disease progression as an entropy-increasing stochastic process. Conclusion: Based on our modeling, metastatic spread may follow predictable pathways. Mapping metastasis not simply by organ site, but by function as either a spreader or sponge fundamentally reframes our understanding of metastatic processes. This model serves as a novel platform from which we may integrate the evolving genomic landscape that drives cancer metastasis. PS-OC Trans

  19. CrossConnects Workshop Series

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

    to offer a series of short, focused workshops on highly specific subjects for discussion between network engineersoperators and domain scientists, especially in areas of Big Data. ...

  20. Using an external surrogate for predictor model training in real-time motion management of lung tumors

    SciTech Connect (OSTI)

    Rottmann, Joerg; Berbeco, Ross

    2014-12-15

    Purpose: Precise prediction of respiratory motion is a prerequisite for real-time motion compensation techniques such as beam, dynamic couch, or dynamic multileaf collimator tracking. Collection of tumor motion data to train the prediction model is required for most algorithms. To avoid exposure of patients to additional dose from imaging during this procedure, the feasibility of training a linear respiratory motion prediction model with an external surrogate signal is investigated and its performance benchmarked against training the model with tumor positions directly. Methods: The authors implement a lung tumor motion prediction algorithm based on linear ridge regression that is suitable to overcome system latencies up to about 300 ms. Its performance is investigated on a data set of 91 patient breathing trajectories recorded from fiducial marker tracking during radiotherapy delivery to the lung of ten patients. The expected 3D geometric error is quantified as a function of predictor lookahead time, signal sampling frequency and history vector length. Additionally, adaptive model retraining is evaluated, i.e., repeatedly updating the prediction model after initial training. Training length for this is gradually increased with incoming (internal) data availability. To assess practical feasibility model calculation times as well as various minimum data lengths for retraining are evaluated. Relative performance of model training with external surrogate motion data versus tumor motion data is evaluated. However, an internal–external motion correlation model is not utilized, i.e., prediction is solely driven by internal motion in both cases. Results: Similar prediction performance was achieved for training the model with external surrogate data versus internal (tumor motion) data. Adaptive model retraining can substantially boost performance in the case of external surrogate training while it has little impact for training with internal motion data. A minimum

  1. Optimal Compensation with Hidden Action and Lump-Sum Payment in a Continuous-Time Model

    SciTech Connect (OSTI)

    Cvitanic, Jaksa Wan, Xuhu Zhang Jianfeng

    2009-02-15

    We consider a problem of finding optimal contracts in continuous time, when the agent's actions are unobservable by the principal, who pays the agent with a one-time payoff at the end of the contract. We fully solve the case of quadratic cost and separable utility, for general utility functions. The optimal contract is, in general, a nonlinear function of the final outcome only, while in the previously solved cases, for exponential and linear utility functions, the optimal contract is linear in the final output value. In a specific example we compute, the first-best principal's utility is infinite, while it becomes finite with hidden action, which is increasing in value of the output. In the second part of the paper we formulate a general mathematical theory for the problem. We apply the stochastic maximum principle to give necessary conditions for optimal contracts. Sufficient conditions are hard to establish, but we suggest a way to check sufficiency using non-convex optimization.

  2. Constraining dark energy models using the lookback time to galaxy clusters and the age of the universe

    SciTech Connect (OSTI)

    Capozziello, S.; Cardone, V.F.; Funaro, M.; Andreon, S.

    2004-12-15

    An impressive amount of different astrophysical data converges towards the picture of a spatially flat Universe undergoing today a phase of accelerated expansion. The nature of the dark energy dominating the energy content of the Universe is still unknown, and a lot of different scenarios are viable candidates to explain cosmic acceleration. Most of the methods employed to test these cosmological models are essentially based on distance measurements to a particular class of objects. A different method, based on the lookback time to galaxy clusters and the age of the Universe, is used here. In particular, we constrain the characterizing parameters of three classes of dark energy cosmological models to see whether they are in agreement with this kind of data, based on time measurements rather than distance observations.

  3. Ownership transfer for non-federate object and time management in developing an hla compliant logistics model.

    SciTech Connect (OSTI)

    Li, Z.

    1998-01-12

    A seaport simulation model, PORTSIM, has been developed for the Department of Defense (DOD) at Argonne National Laboratory. PORTSIM simulates the detailed processes of cargo loading and unloading in a seaport and provides throughput capability, resource utilization, and other important information on the bottlenecks in a seaport operation, which are crucial data in determining troop and equipment deployment capability. There are two key problems to solve in developing the HLA-compliant PORTSIM model. The first is the cargo object ownership transfer problem. In PORTSIM, cargo items, e.g. vehicles, containers, and pallets, are objects having asset attributes. Cargo comes to a seaport for loading or unloading. The ownership of a cargo object transfers from its carrier to the port and then from the port to a new carrier. Each owner of the cargo object is responsible for publishing and updating the attributes of the cargo object when it has the ownership. This creates a unique situation in developing the PORTSIM federate object model, that is, the ownership of the object instead of the attributes needs to be changed in handling the cargo object in the PORTSIM federate. The ownership management service provided by the current RTI does not directly address this issue. The second is the time management issue. PORTSIM is an event-driven simulation that models seaport operations over time. To make PORTSIM HLA compliant, time management must be addressed to allow for synchronization with other simulation models. This paper attempts to address these two issues and methodologies developed for solving these two problems.

  4. Determination of equilibrium electron temperature and times using an electron swarm model with BOLSIG+ calculated collision frequencies and rate coefficients

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

    Pusateri, Elise N.; Morris, Heidi E.; Nelson, Eric M.; Ji, Wei

    2015-08-04

    Electromagnetic pulse (EMP) events produce low-energy conduction electrons from Compton electron or photoelectron ionizations with air. It is important to understand how conduction electrons interact with air in order to accurately predict EMP evolution and propagation. An electron swarm model can be used to monitor the time evolution of conduction electrons in an environment characterized by electric field and pressure. Here a swarm model is developed that is based on the coupled ordinary differential equations (ODEs) described by Higgins et al. (1973), hereinafter HLO. The ODEs characterize the swarm electric field, electron temperature, electron number density, and drift velocity. Importantmore »swarm parameters, the momentum transfer collision frequency, energy transfer collision frequency, and ionization rate, are calculated and compared to the previously reported fitted functions given in HLO. These swarm parameters are found using BOLSIG+, a two term Boltzmann solver developed by Hagelaar and Pitchford (2005), which utilizes updated cross sections from the LXcat website created by Pancheshnyi et al. (2012). We validate the swarm model by comparing to experimental effective ionization coefficient data in Dutton (1975) and drift velocity data in Ruiz-Vargas et al. (2010). In addition, we report on electron equilibrium temperatures and times for a uniform electric field of 1 StatV/cm for atmospheric heights from 0 to 40 km. We show that the equilibrium temperature and time are sensitive to the modifications in the collision frequencies and ionization rate based on the updated electron interaction cross sections.« less

  5. Determination of equilibrium electron temperature and times using an electron swarm model with BOLSIG+ calculated collision frequencies and rate coefficients

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

    Pusateri, Elise N.; Morris, Heidi E.; Nelson, Eric M.; Ji, Wei

    2015-08-04

    Electromagnetic pulse (EMP) events produce low-energy conduction electrons from Compton electron or photoelectron ionizations with air. It is important to understand how conduction electrons interact with air in order to accurately predict EMP evolution and propagation. An electron swarm model can be used to monitor the time evolution of conduction electrons in an environment characterized by electric field and pressure. Here a swarm model is developed that is based on the coupled ordinary differential equations (ODEs) described by Higgins et al. (1973), hereinafter HLO. The ODEs characterize the swarm electric field, electron temperature, electron number density, and drift velocity. Importantmore » swarm parameters, the momentum transfer collision frequency, energy transfer collision frequency, and ionization rate, are calculated and compared to the previously reported fitted functions given in HLO. These swarm parameters are found using BOLSIG+, a two term Boltzmann solver developed by Hagelaar and Pitchford (2005), which utilizes updated cross sections from the LXcat website created by Pancheshnyi et al. (2012). We validate the swarm model by comparing to experimental effective ionization coefficient data in Dutton (1975) and drift velocity data in Ruiz-Vargas et al. (2010). In addition, we report on electron equilibrium temperatures and times for a uniform electric field of 1 StatV/cm for atmospheric heights from 0 to 40 km. We show that the equilibrium temperature and time are sensitive to the modifications in the collision frequencies and ionization rate based on the updated electron interaction cross sections.« less

  6. Determination of equilibrium electron temperature and times using an electron swarm model with BOLSIG+ calculated collision frequencies and rate coefficients

    SciTech Connect (OSTI)

    Pusateri, Elise N.; Morris, Heidi E.; Nelson, Eric M.; Ji, Wei

    2015-08-04

    Electromagnetic pulse (EMP) events produce low-energy conduction electrons from Compton electron or photoelectron ionizations with air. It is important to understand how conduction electrons interact with air in order to accurately predict EMP evolution and propagation. An electron swarm model can be used to monitor the time evolution of conduction electrons in an environment characterized by electric field and pressure. Here a swarm model is developed that is based on the coupled ordinary differential equations (ODEs) described by Higgins et al. (1973), hereinafter HLO. The ODEs characterize the swarm electric field, electron temperature, electron number density, and drift velocity. Important swarm parameters, the momentum transfer collision frequency, energy transfer collision frequency, and ionization rate, are calculated and compared to the previously reported fitted functions given in HLO. These swarm parameters are found using BOLSIG+, a two term Boltzmann solver developed by Hagelaar and Pitchford (2005), which utilizes updated cross sections from the LXcat website created by Pancheshnyi et al. (2012). We validate the swarm model by comparing to experimental effective ionization coefficient data in Dutton (1975) and drift velocity data in Ruiz-Vargas et al. (2010). In addition, we report on electron equilibrium temperatures and times for a uniform electric field of 1 StatV/cm for atmospheric heights from 0 to 40 km. We show that the equilibrium temperature and time are sensitive to the modifications in the collision frequencies and ionization rate based on the updated electron interaction cross sections.

  7. A numerical study of short residence time FCC riser flows with a new flow/kinetics modeling technique.

    SciTech Connect (OSTI)

    Chang, S. L.

    1998-08-25

    Fluid Catalytic Cracking (FCC) technology is the most important process used by the refinery industry to convert crude oil to valuable lighter products such as gasoline. New and modified processes are constantly developed by refinery companies to improve their global competitiveness and meet more stringent environmental regulations. Short residence time FCC riser reactor is one of the advanced processes that the refining industry is actively pursuing because it can improve the yield selectivity and efficiency of an FCC unit. However, as the residence time becomes shorter, the impact of the mixing between catalyst and feed oil at the feed injection region on the product yield becomes more significant. Currently, most FCC computer models used by the refineries perform sophisticated kinetic calculations on simplified flow field and can not be used to evaluate the impact of fluid mixing on the performance of an FCC unit. Argonne National Laboratory (AFL) is developing a computational fluid dynamic (CFD) code ICRKFLO for FCC riser flow modeling. The code, employing hybrid hydrodynamic-chemical kinetic coupling techniques, is used to investigate the effect of operating and design conditions on the product yields of FCC riser reactors. Numerical calculations were made using the code to examine the impacts of the operating and design conditions on the product yields. The controlling parameters under investigation include the residence time, reaction temperature, and catalyst/oil ratio. This paper describes the CFD code, presents computation results, and discusses the effects of operating conditions on the performance of short residence time FCC riser reactors.

  8. Three-dimensional transient model for time-domain free-carrier absorption measurement of excess carriers in silicon wafers

    SciTech Connect (OSTI)

    Ren, Shengdong; Huang, Qiuping; Li, Bincheng

    2013-12-28

    A three-dimensional transient model for time-domain (modulated) free-carrier absorption (FCA) measurement was developed to describe the transport dynamics of photo-generated excess carriers in silicon (Si) wafers. With the developed transient model, numerical simulations were performed to investigate the dependences of the waveforms of the transient FCA signals on the electronic transport parameters of Si wafers and the geometric parameters of the FCA experiment. Experimental waveforms of FCA signals of both n- and p-type Si wafers with resistivity ranging 1–38 Ω·cm were then fitted to the three-dimensional transient model to extract simultaneously and unambiguously the transport parameters of Si wafers, namely, the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity via multi-parameter fitting. A basic agreement between the extracted parameter values and the literature values was obtained.

  9. Sustained virological response with intravenous silibinin: individualized IFN-free therapy via real-time modelling of HCV kinetics

    SciTech Connect (OSTI)

    Dahari, Harel; Shteingart, Shimon; Gafanovich, Inna; Cotler, Scott J.; D'Amato, Massimo; Pohl, Ralf T.; Weiss, Gali; Ashkenazi, Yaakov J.; Tichler, Thomas; Goldin, Eran; Lurie, Yoav

    2014-10-10

    Providing here our aims and project background, we note that intravenous silibinin (SIL) is a potent antiviral agent against hepatitis C virus (HCV) genotype-1. In this proof of concept case-study we tested: (i) whether interferon-alfa (IFN)-free treatment with SIL plus ribavirin (RBV) can achieve sustained virological response (SVR); (ii) whether SIL is safe and feasible for prolonged duration of treatment and (iii) whether mathematical modelling of early on-treatment HCV kinetics can guide duration of therapy to achieve SVR. With our method, a 44 year-old female HCV-(genotype-1)-infected patient who developed severe psychiatric adverse events to a previous course of pegIFN+RBV, initiated combination treatment with 1200 mg/day of SIL, 1200 mg/day of RBV and 6000 u/day vitamin D. Blood samples were collected frequently till week 4, thereafter every 1-12 weeks until the end of therapy. The standard biphasic mathematical model with time-varying SIL effectiveness was used to predict the duration of therapy to achieve SVR. Our results show that, based on modelling the observed viral kinetics during the first 3 weeks of treatment, SVR was predicted to be achieved within 34 weeks of therapy. Provided with this information, the patient agreed to complete 34 weeks of treatment. IFN-free treatment with SIL+RBV was feasible, safe and achieved SVR (week-33). In conclusion, we report, for the first time, the use of real-time mathematical modelling of HCV kinetics to individualize duration of IFN-free therapy and to empower a patient to participate in shared decision making regarding length of treatment. SIL-based individualized therapy provides a treatment option for patients who do not respond to or cannot receive other HCV agents and should be further validated.

  10. Sustained virological response with intravenous silibinin: individualized IFN-free therapy via real-time modelling of HCV kinetics

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

    Dahari, Harel; Shteingart, Shimon; Gafanovich, Inna; Cotler, Scott J.; D'Amato, Massimo; Pohl, Ralf T.; Weiss, Gali; Ashkenazi, Yaakov J.; Tichler, Thomas; Goldin, Eran; et al

    2014-10-10

    Providing here our aims and project background, we note that intravenous silibinin (SIL) is a potent antiviral agent against hepatitis C virus (HCV) genotype-1. In this proof of concept case-study we tested: (i) whether interferon-alfa (IFN)-free treatment with SIL plus ribavirin (RBV) can achieve sustained virological response (SVR); (ii) whether SIL is safe and feasible for prolonged duration of treatment and (iii) whether mathematical modelling of early on-treatment HCV kinetics can guide duration of therapy to achieve SVR. With our method, a 44 year-old female HCV-(genotype-1)-infected patient who developed severe psychiatric adverse events to a previous course of pegIFN+RBV, initiatedmore » combination treatment with 1200 mg/day of SIL, 1200 mg/day of RBV and 6000 u/day vitamin D. Blood samples were collected frequently till week 4, thereafter every 1-12 weeks until the end of therapy. The standard biphasic mathematical model with time-varying SIL effectiveness was used to predict the duration of therapy to achieve SVR. Our results show that, based on modelling the observed viral kinetics during the first 3 weeks of treatment, SVR was predicted to be achieved within 34 weeks of therapy. Provided with this information, the patient agreed to complete 34 weeks of treatment. IFN-free treatment with SIL+RBV was feasible, safe and achieved SVR (week-33). In conclusion, we report, for the first time, the use of real-time mathematical modelling of HCV kinetics to individualize duration of IFN-free therapy and to empower a patient to participate in shared decision making regarding length of treatment. SIL-based individualized therapy provides a treatment option for patients who do not respond to or cannot receive other HCV agents and should be further validated.« less

  11. DOE Cyber Distinguished Speaker Series

    Broader source: Energy.gov [DOE]

    Join us at the Department of Energy’s Cyber Distinguished Speaker Series on Wednesday, 13 January 2016, for an opportunity to expand your knowledge and awareness of today’s most pressing cyber issues.

  12. Castle series, 1954. Technical report

    SciTech Connect (OSTI)

    Martin, E.J.; Rowland, R.H.

    1982-04-01

    CASTLE was an atmospheric nuclear weapons test series held in the Marshall Islands at Enewetak and Bikini atolls in 1954. This is a report of DOD peronnel in CASTLE with an emphasis on operations and radiological safety.

  13. Solar Permitting & Inspection Webinar Series

    Broader source: Energy.gov [DOE]

    ICLEI Local Governments for Sustainability U.S.A. and the Interstate Renewable Energy Council, Inc. (IREC) present a series of three webinars on Solar Permitting & Inspection. As part of the U...

  14. PARC Seminar Series featuring Jan Jaworski | Photosynthetic Antenna...

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

    Jaworski PARC Seminar Series featuring Jan Jaworski Camelina as a model for oilseed biotechnology April 16, 2013 - 11:00am to 12:00pm Brauer 012, Washington University in St. Louis...

  15. One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma

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

    Chaplin, Vernon H.; Bellan, Paul M.

    2015-12-28

    A time-dependent two-fluid model has been developed to understand axial variations in the plasma parameters in a very high density (peak ne~ > 5x1019 m–3) argon inductively coupled discharge in a long 1.1 cm radius tube. The model equations are written in 1D, with radial losses to the tube walls accounted for by the inclusion of effective particle and energy sink terms. The ambipolar diffusion equation and electron energy equation are solved to find the electron density ne(z,t) and temperature Te(z,t), and the populations of the neutral argon 4s metastable, 4s resonant, and 4p excited state manifolds are calculated inmore » order to determine the stepwise ionization rate and calculate radiative energy losses. The model has been validated through comparisons with Langmuir probe ion saturation current measurements; close agreement between the simulated and measured axial plasma density profiles and the initial density rise rate at each location was obtained at pAr = 30-60 mTorr. Lastly, we present detailed results from calculations at 60 mTorr, including the time-dependent electron temperature, excited state populations, and energy budget within and downstream of the radiofrequency (RF) antenna.« less

  16. One-dimensional time-dependent fluid model of a very high density low-pressure inductively coupled plasma

    SciTech Connect (OSTI)

    Chaplin, Vernon H.; Bellan, Paul M.

    2015-12-28

    A time-dependent two-fluid model has been developed to understand axial variations in the plasma parameters in a very high density (peak ne~ > 5x1019 m–3) argon inductively coupled discharge in a long 1.1 cm radius tube. The model equations are written in 1D, with radial losses to the tube walls accounted for by the inclusion of effective particle and energy sink terms. The ambipolar diffusion equation and electron energy equation are solved to find the electron density ne(z,t) and temperature Te(z,t), and the populations of the neutral argon 4s metastable, 4s resonant, and 4p excited state manifolds are calculated in order to determine the stepwise ionization rate and calculate radiative energy losses. The model has been validated through comparisons with Langmuir probe ion saturation current measurements; close agreement between the simulated and measured axial plasma density profiles and the initial density rise rate at each location was obtained at pAr = 30-60 mTorr. Lastly, we present detailed results from calculations at 60 mTorr, including the time-dependent electron temperature, excited state populations, and energy budget within and downstream of the radiofrequency (RF) antenna.

  17. Staggered-grid finite-difference acoustic modeling with the Time-Domain Atmospheric Acoustic Propagation Suite (TDAAPS).

    SciTech Connect (OSTI)

    Aldridge, David Franklin; Collier, Sandra L.; Marlin, David H.; Ostashev, Vladimir E.; Symons, Neill Phillip; Wilson, D. Keith

    2005-05-01

    This document is intended to serve as a users guide for the time-domain atmospheric acoustic propagation suite (TDAAPS) program developed as part of the Department of Defense High-Performance Modernization Office (HPCMP) Common High-Performance Computing Scalable Software Initiative (CHSSI). TDAAPS performs staggered-grid finite-difference modeling of the acoustic velocity-pressure system with the incorporation of spatially inhomogeneous winds. Wherever practical the control structure of the codes are written in C++ using an object oriented design. Sections of code where a large number of calculations are required are written in C or F77 in order to enable better compiler optimization of these sections. The TDAAPS program conforms to a UNIX style calling interface. Most of the actions of the codes are controlled by adding flags to the invoking command line. This document presents a large number of examples and provides new users with the necessary background to perform acoustic modeling with TDAAPS.

  18. OSPREY Model

    SciTech Connect (OSTI)

    Veronica J. Rutledge

    2013-01-01

    The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of off-gas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data is obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data and parameters were input into the adsorption model to develop models specific for krypton adsorption. The same can be done for iodine, xenon, and tritium. The model will be validated with experimental breakthrough curves. Customers will be given access to

  19. ARMY SERiWE FORCES

    Office of Legacy Management (LM)

    ' This doc~omnt consists tif-..$---..-- PaWs ?5-i3s4 " No.,J ______ d&---.copies. series.-f;;i, ' ARMY SERiWE FORCES UNITED STATES ' ENGINEER OFFICE MANHP.~AN Dwmtcr CHIWOO A\RU o,,,c* P. 0. 90x 3140 A CHICA so, ILrlNole 20 June 1945 F' '2 0 Subject: Licenae Agreement - International Pulverizing Corporation - Subcoritract #7401-37-82. To: The District~Eqinssr, U. S. Engineer Office, Manhattan District, Oak Ridge, Tennessee. Attention: Contract Section. As llsted'below, there are

  20. DOE Cyber Distinguished Speaker Series | Department of Energy

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

    DOE Cyber Distinguished Speaker Series DOE Cyber Distinguished Speaker Series Featured Speaker: Dr. Winfried K. Hensinger Date: August 5, 2016 Time: 11:00 am - 12:00 pm Location: DOE Headquarters, Forrestal Auditorium, Washington, DC Winfried K. Hensinger.jpg Dr. Winfried Hensinger - Professor of Quantum Technologies, Ion Quantum Technology Group, Department of Physics and Astronomy, University of Sussex Winfried Hensinger obtained his undergraduate degree at the Ruprechts-Karls University in

  1. Summer Series 2012 - Shashi Buluswar

    ScienceCinema (OSTI)

    Shashi Buluswar

    2013-06-24

    The last installment of the "Summer Series of Conversations" took place Wednesday, August 1, with guest Shashi Buluswar, the executive director of the LBNL Institute for Globally Transformative Technologies (LIGTT). The Institute seeks to foster the discovery, development and deployment of a generation of low-carbon, affordable technologies that will advance sustainable methods to fight global poverty. The event, was hosted by Public Affairs Head Jeff Miller.

  2. Summer Series 2012 - Shashi Buluswar

    SciTech Connect (OSTI)

    Shashi Buluswar

    2012-08-08

    The last installment of the "Summer Series of Conversations" took place Wednesday, August 1, with guest Shashi Buluswar, the executive director of the LBNL Institute for Globally Transformative Technologies (LIGTT). The Institute seeks to foster the discovery, development and deployment of a generation of low-carbon, affordable technologies that will advance sustainable methods to fight global poverty. The event, was hosted by Public Affairs Head Jeff Miller.

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

    SciTech Connect (OSTI)

    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; Percival, Carl; Coe, H.; Jones, Roderic L.; McFiggans, Gordon

    2015-02-09

    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 (correlations 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 μg kg−1air, compared with measurements of 1.0–1.5 μg 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 NO

  4. SU-E-J-205: Monte Carlo Modeling of Ultrasound Probes for Real-Time Ultrasound Image-Guided Radiotherapy

    SciTech Connect (OSTI)

    Hristov, D; Schlosser, J; Bazalova, M; Chen, J

    2014-06-01

    Purpose: To quantify the effect of ultrasound (US) probe beam attenuation for radiation therapy delivered under real-time US image guidance by means of Monte Carlo (MC) simulations. Methods: MC models of two Philips US probes, an X6-1 matrix-array transducer and a C5-2 curved-array transducer, were built based on their CT images in the EGSnrc BEAMnrc and DOSXYZnrc codes. Due to the metal parts, the probes were scanned in a Tomotherapy machine with a 3.5 MV beam. Mass densities in the probes were assigned based on an electron density calibration phantom consisting of cylinders with mass densities between 0.2–8.0 g/cm{sup 3}. Beam attenuation due to the probes was measured in a solid water phantom for a 6 MV and 15 MV 15x15 cm{sup 2} beam delivered on a Varian Trilogy linear accelerator. The dose was measured with the PTW-729 ionization chamber array at two depths and compared to MC simulations. The extreme case beam attenuation expected in robotic US image guided radiotherapy for probes in upright position was quantified by means of MC simulations. Results: The 3.5 MV CT number to mass density calibration curve was found to be linear with R{sup 2} > 0.99. The maximum mass densities were 4.6 and 4.2 g/cm{sup 3} in the C5-2 and X6-1 probe, respectively. Gamma analysis of the simulated and measured doses revealed that over 98% of measurement points passed the 3%/3mm criteria for both probes and measurement depths. The extreme attenuation for probes in upright position was found to be 25% and 31% for the C5-2 and X6-1 probe, respectively, for both 6 and 15 MV beams at 10 cm depth. Conclusion: MC models of two US probes used for real-time image guidance during radiotherapy have been built. As a Result, radiotherapy treatment planning with the imaging probes in place can now be performed. J Schlosser is an employee of SoniTrack Systems, Inc. D Hristov has financial interest in SoniTrack Systems, Inc.

  5. Methyl Formate Oxidation: Speciation Data, Laminar Burning Velocities, Ignition Delay Times and a Validated Chemical Kinetic Model

    SciTech Connect (OSTI)

    Dooley, S.; Burke, M. P.; Chaos, M.; Stein, Y.; Dryer, F. L.; Zhukov, V. P.; Finch, O.; Simmie, J. M.; Curran, H. J.

    2010-07-16

    The oxidation of methyl formate (CH{sub 3}OCHO) has been studied in three experimental environments over a range of applied combustion relevant conditions: 1. A variable-pressure flow reactor has been used to quantify reactant, major intermediate and product species as a function of residence time at 3 atm and 0.5% fuel concentration for oxygen/fuel stoichiometries of 0.5, 1.0, and 1.5 at 900 K, and for pyrolysis at 975 K. 2. Shock tube ignition delays have been determined for CH{sub 3}OCHO/O{sub 2}/Ar mixtures at pressures of ? 2.7, 5.4, and 9.2 atm and temperatures of 12751935 K for mixture compositions of 0.5% fuel (at equivalence ratios of 1.0, 2.0, and 0.5) and 2.5% fuel (at an equivalence ratio of 1.0). 3. Laminar burning velocities of outwardly propagating spherical CH{sub 3}OCHO/air flames have been determined for stoichiometries ranging from 0.81.6, at atmospheric pressure using a pressure-release-type high-pressure chamber. A detailed chemical kinetic model has been constructed, validated against, and used to interpret these experimental data. The kinetic model shows that methyl formate oxidation proceeds through concerted elimination reactions, principally forming methanol and carbon monoxide as well as through bimolecular hydrogen abstraction reactions. The relative importance of elimination versus abstraction was found to depend on the particular environment. In general, methyl formate is consumed exclusively through molecular decomposition in shock tube environments, while at flow reactor and freely propagating premixed flame conditions, there is significant competition between hydrogen abstraction and concerted elimination channels. It is suspected that in diffusion flame configurations the elimination channels contribute more significantly than in premixed environments.

  6. Modeling a thermionic energy converter using finite-difference time-domain particle-in-cell simulations

    SciTech Connect (OSTI)

    Lo, F. S.; Lee, T. H.; Lu, P. S.; Ragan-Kelley, B.; Plasma Theory and Simulation Group, University of California, Berkeley, California 94720 ; Minnich, A.; Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125 ; Lin, M. C.; Verboncoeur, J. P.; Department of Electrical and Computing Engineering, Michigan State University, East Lansing, Michigan 48824

    2014-02-15

    A thermionic energy converter (TEC) is a static device that converts heat directly into electricity by boiling electrons off a hot emitter surface across a small inter-electrode gap to a cooler collector surface. The main challenge in TECs is overcoming the space charge limit, which limits the current transmitted across a gap of a given voltage and width. We have verified the feasibility of studying and developing a TEC using a bounded finite-difference time-domain particle-in-cell plasma simulation code, OOPD1, developed by Plasma Theory and Simulation Group, formerly at UC Berkeley and now at Michigan State University. In this preliminary work, a TEC has been modeled kinetically using OOPD1, and the accuracy has been verified by comparing with an analytically solvable case, giving good agreement. With further improvement of the code, one will be able to quickly and cheaply analyze space charge effects, and seek designs that mitigate the space charge effect, allowing TECs to become more efficient and cost-effective.

  7. Lattice Boltzmann simulation of solute transport in heterogeneous porous media with conduits to estimate macroscopic continuous time random walk model parameters

    SciTech Connect (OSTI)

    Anwar, S.; Cortis, A.; Sukop, M.

    2008-10-20

    Lattice Boltzmann models simulate solute transport in porous media traversed by conduits. Resulting solute breakthrough curves are fitted with Continuous Time Random Walk models. Porous media are simulated by damping flow inertia and, when the damping is large enough, a Darcy's Law solution instead of the Navier-Stokes solution normally provided by the lattice Boltzmann model is obtained. Anisotropic dispersion is incorporated using a direction-dependent relaxation time. Our particular interest is to simulate transport processes outside the applicability of the standard Advection-Dispersion Equation (ADE) including eddy mixing in conduits. The ADE fails to adequately fit any of these breakthrough curves.

  8. The Integrated TIGER Series Codes

    Energy Science and Technology Software Center (OSTI)

    2006-01-15

    ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with anmore » input scheme based on order-independent descriptive keywords that makes maximum use of defaults and intemal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2) multigroup codes with adjoint transport capabilities, (3) parallel implementations of all ITS codes, (4) a general purpose geometry engine for linking with CAD or other geometry formats, and (5) the Cholla facet geometry library. Moreover, the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.« less

  9. H-Series Cast Austenitic Stainless Steels

    Broader source: Energy.gov [DOE]

    Cast H-Series austenitic steels are used extensively in several industries for a broad range of high-temperature applications. The H-Series stainless steels have evolved over many years of complex...

  10. 2016 Webinar Series Flier | Department of Energy

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

    Webinar Series Flier 2016 Webinar Series Flier The U.S. Department of Energy (DOE) Office of Indian Energy Policy and Programs and the Western Area Power Administration are pleased to co-sponsor the 2016 Tribal Clean Energy Webinar Series. The 11 webinars in the series will provide information to tribal leaders and staff on strategic energy planning, power marketing, clean energy, and how to enhance the local economy and move toward energy independence. Learn more and register for webinars

  11. The effect of large-scale model time step and multiscale coupling frequency on cloud climatology, vertical structure, and rainfall extremes in a superparameterized GCM

    SciTech Connect (OSTI)

    Yu, Sungduk; Pritchard, Michael S.

    2015-12-17

    The effect of global climate model (GCM) time step—which also controls how frequently global and embedded cloud resolving scales are coupled—is examined in the Superparameterized Community Atmosphere Model ver 3.0. Systematic bias reductions of time-mean shortwave cloud forcing (~10 W/m2) and longwave cloud forcing (~5 W/m2) occur as scale coupling frequency increases, but with systematically increasing rainfall variance and extremes throughout the tropics. An overarching change in the vertical structure of deep tropical convection, favoring more bottom-heavy deep convection as a global model time step is reduced may help orchestrate these responses. The weak temperature gradient approximation is more faithfully satisfied when a high scale coupling frequency (a short global model time step) is used. These findings are distinct from the global model time step sensitivities of conventionally parameterized GCMs and have implications for understanding emergent behaviors of multiscale deep convective organization in superparameterized GCMs. Lastly, the results may also be useful for helping to tune them.

  12. The effect of large-scale model time step and multiscale coupling frequency on cloud climatology, vertical structure, and rainfall extremes in a superparameterized GCM

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

    Yu, Sungduk; Pritchard, Michael S.

    2015-12-17

    The effect of global climate model (GCM) time step—which also controls how frequently global and embedded cloud resolving scales are coupled—is examined in the Superparameterized Community Atmosphere Model ver 3.0. Systematic bias reductions of time-mean shortwave cloud forcing (~10 W/m2) and longwave cloud forcing (~5 W/m2) occur as scale coupling frequency increases, but with systematically increasing rainfall variance and extremes throughout the tropics. An overarching change in the vertical structure of deep tropical convection, favoring more bottom-heavy deep convection as a global model time step is reduced may help orchestrate these responses. The weak temperature gradient approximation is more faithfullymore » satisfied when a high scale coupling frequency (a short global model time step) is used. These findings are distinct from the global model time step sensitivities of conventionally parameterized GCMs and have implications for understanding emergent behaviors of multiscale deep convective organization in superparameterized GCMs. Lastly, the results may also be useful for helping to tune them.« less

  13. A new time-dependent analytic model for radiation-induced photocurrent in finite 1D epitaxial diodes.

    SciTech Connect (OSTI)

    Verley, Jason C.; Axness, Carl L.; Hembree, Charles Edward; Keiter, Eric Richard; Kerr, Bert

    2012-04-01

    Photocurrent generated by ionizing radiation represents a threat to microelectronics in radiation environments. Circuit simulation tools such as SPICE [1] can be used to analyze these threats, and typically rely on compact models for individual electrical components such as transistors and diodes. Compact models consist of a handful of differential and/or algebraic equations, and are derived by making simplifying assumptions to any of the many semiconductor transport equations. Historically, many photocurrent compact models have suffered from accuracy issues due to the use of qualitative approximation, rather than mathematically correct solutions to the ambipolar diffusion equation. A practical consequence of this inaccuracy is that a given model calibration is trustworthy over only a narrow range of operating conditions. This report describes work to produce improved compact models for photocurrent. Specifically, an analytic model is developed for epitaxial diode structures that have a highly doped subcollector. The analytic model is compared with both numerical TCAD calculations, as well as the compact model described in reference [2]. The new analytic model compares well against TCAD over a wide range of operating conditions, and is shown to be superior to the compact model from reference [2].

  14. Summary of results from the Series 2 and Series 3 NNWSI [Nevada Nuclear Waste Storage Investigations] bare fuel dissolution tests

    SciTech Connect (OSTI)

    Wilson, C.N.

    1987-11-01

    The Nevada Nuclear Waste Storage Investigations (NNWSI) Project is studying dissolution and radionuclide release behavior of spent nuclear fuel in Nevada Test Site groundwater. Specimens were tested for multiple cycles in J-13 well water. The Series 2 tests were run in unsealed silica vessels under ambient hot cell air (25{sup 0}C) for five cycles for a total of 34 months. The Series 3 tests were run in sealed stainless steel vessels at 25{sup 0}C and 85{sup 0}C for three cycles for a total of 15 months. Selected summary results from Series 2 and Series 3 tests with bare fuel specimens are reported. Uranium concentrations in later test cycles ranged from 1 to 2 {mu}g/ml in the Series 2 Tests versus about 0.1 to 0.4 {mu}g/ml in Series 3 with the lowest concentrations occurring in the 85{sup 0}C tests. Preferential release of fission products Cs, I, Sr and Tc, and activation product C-14, was indicated relative to the actinides. Tc-99 and Cs-137 activities measured in solution after Cycle 1 increased linearly with time, with the rate of increase greater at 85{sup 0}C than at 25{sup 0}C. 8 refs., 8 figs., 3 tabs.

  15. Data Tools & Models - U.S. Energy Information Administration (EIA)

    U.S. Energy Information Administration (EIA) Indexed Site

    Data Tools & Models Glossary › FAQS › Overview Data Tools Time Series Models & Documentation EIA has a vast amount of data, reports, forecasts, analytical content, and documentation to assist researchers working on energy topics. For users eager to dive deeper into our content, we have assembled tools to customize searches, view specific data sets, study detailed documentation, and access time-series data. Application Programming Interface (API): The API allows computers to more

  16. Fermilab Arts & Lecture Series Tickets

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

    Telephone For information and tickets you may also call 630-840-ARTS (630-840-2787). An answering machine will take your confidential message during times that the box office ...

  17. Josephson oscillations in a series array Josephson voltage standard

    SciTech Connect (OSTI)

    Meyer, H.G.; Krech, W.; Mikolajczak, B.

    1989-06-01

    Josephson oscillations in a large series array of Josephson junctions designed as a superconducting microwave transmission line are studied. For descriptions of the Josephson junctions both the Stewart--McCumber model and the Werthamer model are used. The attenuation of the Josephson oscillations in the considered array is composed of two terms rising from the stripline and from the Josephson junctions. The latter one is of increasing significance for lower than usually applied drive frequencies.

  18. A Collaborative Ecosystem Model for Metagenomics Data Preservation (MICW - Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

    SciTech Connect (OSTI)

    Cochrane, Guy

    2011-10-12

    EMBL-EBI's Guy Cochrane on "A Collaborative Ecosystem Model for Metagenomics Data Preservation" at the Metagenomics Informatics Challenges Workshop held at the DOE JGI on October 12-13, 2011.

  19. A Collaborative Ecosystem Model for Metagenomics Data Preservation (MICW - Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

    ScienceCinema (OSTI)

    Cochrane, Guy [EMBL-EBI

    2013-01-22

    EMBL-EBI's Guy Cochrane on "A Collaborative Ecosystem Model for Metagenomics Data Preservation" at the Metagenomics Informatics Challenges Workshop held at the DOE JGI on October 12-13, 2011.

  20. Lab's 70th Anniversary lecture series

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

    Lab's 70th Anniversary Lecture Series Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Lab's 70th Anniversary lecture series The Bradbury Science Museum is hosting a public lecture series with a different talk held each month through the end of the year. February 1, 2013 dummy image Read our archives. Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email All

  1. CLEAN Webinar Series 5 | Open Energy Information

    Open Energy Info (EERE)

    CLEAN Webinar Series 5 Jump to: navigation, search Home | About | Inventory | Partnerships | Capacity Building | Webinars | Reports | Events | News | List Serve WebinarHeader.JPG...

  2. Commercial Building Envelope Technology Webinar Series

    Broader source: Energy.gov [DOE]

    U.S. DOE’s Better Building Alliance and Oak Ridge National Laboratory (ORNL) are hosting a webinar series focused on advancing envelope technologies in commercial buildings.

  3. Transportation Energy Futures Series: Alternative Fuel Infrastructure...

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

    for Low-Carbon Scenarios TRANSPORTATION ENERGY FUTURES SERIES: Alternative Fuel ... A Study Sponsored by U.S. Department of Energy Office of Energy Efficiency and Renewable ...

  4. SERI QC Solar Data Quality Assessment Software

    Energy Science and Technology Software Center (OSTI)

    1994-12-31

    SERI QC is a mathematical software package that assesses the quality of solar radiation data. The SERI QC software is a function written in the C programming language. IT IS NOT A STANDALONE SOFTWARE APPLICATION. The user must write the calling application that requires quality assessment of solar data. The C function returns data quality flags to the calling program. A companion program, QCFIT, is a standalone Windows application that provides support files for themore » SERI QC function (data quality boundaries). The QCFIT software can also be used as an analytical tool for visualizing solar data quality independent of the SERI QC function.« less

  5. Better Buildings Residential Network Program Sustainability Series...

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

    Series Mastermind Call: Connecting the Dots Between the Real Estate Market and Residential Energy Efficiency Featuring Host: Rich Dooley, Arlington County, VA Call Slides and ...

  6. Transportation Energy Futures Series: Projected Biomass Utilization...

    Office of Scientific and Technical Information (OSTI)

    Transportation Energy Futures Series: Projected Biomass Utilization for Fuels and Power in a Mature Market Ruth, M.; Mai, T.; Newes, E.; Aden, A.; Warner, E.; Uriarte, C.; Inman,...

  7. A staggered-grid finite-difference scheme optimized in the timespace domain for modeling scalar-wave propagation in geophysical problems

    SciTech Connect (OSTI)

    Tan, Sirui; Huang, Lianjie

    2014-11-01

    For modeling scalar-wave propagation in geophysical problems using finite-difference schemes, optimizing the coefficients of the finite-difference operators can reduce numerical dispersion. Most optimized finite-difference schemes for modeling seismic-wave propagation suppress only spatial but not temporal dispersion errors. We develop a novel optimized finite-difference scheme for numerical scalar-wave modeling to control dispersion errors not only in space but also in time. Our optimized scheme is based on a new stencil that contains a few more grid points than the standard stencil. We design an objective function for minimizing relative errors of phase velocities of waves propagating in all directions within a given range of wavenumbers. Dispersion analysis and numerical examples demonstrate that our optimized finite-difference scheme is computationally up to 2.5 times faster than the optimized schemes using the standard stencil to achieve the similar modeling accuracy for a given 2D or 3D problem. Compared with the high-order finite-difference scheme using the same new stencil, our optimized scheme reduces 50 percent of the computational cost to achieve the similar modeling accuracy. This new optimized finite-difference scheme is particularly useful for large-scale 3D scalar-wave modeling and inversion.

  8. Hydrogen and Fuel Cells Webinar Series Kickoff | Department of...

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

    Webinar Series Kickoff Hydrogen and Fuel Cells Webinar Series Kickoff Presented at the State and Regional Initiatives Informational Call and Meeting Series Relaunch Introduction on ...

  9. Development of a High Resolution, Real Time, Distribution-Level Metering System and Associated Visualization, Modeling, and Data Analysis Functions

    SciTech Connect (OSTI)

    Bank, J.; Hambrick, J.

    2013-05-01

    NREL is developing measurement devices and a supporting data collection network specifically targeted at electrical distribution systems to support research in this area. This paper describes the measurement network which is designed to apply real-time and high speed (sub-second) measurement principles to distribution systems that are already common for the transmission level in the form of phasor measurement units and related technologies.

  10. Formative time of breakdown modeled for the ignition of air and n-butane mixtures using effective ionization coefficients

    SciTech Connect (OSTI)

    Kudryavtsev, A. A.; Popugaev, S. D.; Demidov, V. I.; Adams, S. F.; Jiao, C. Q.

    2008-12-15

    It is shown that simulations of ignition by electric arc discharge in n-butane and air mixtures have interesting features, which deviate from results obtained by simple extension of calculations based on methanelike fuels. In particular, it is demonstrated that lowering the temperature of the n-butane-air mixture before ignition under certain conditions will actually decrease the ignition stage time as well as the required electric field.

  11. Discrete-Time Pricing and Optimal Exercise of American Perpetual Warrants in the Geometric Random Walk Model

    SciTech Connect (OSTI)

    Vanderbei, Robert J.; P Latin-Small-Letter-Dotless-I nar, Mustafa C.; Bozkaya, Efe B.

    2013-02-15

    An American option (or, warrant) is the right, but not the obligation, to purchase or sell an underlying equity at any time up to a predetermined expiration date for a predetermined amount. A perpetual American option differs from a plain American option in that it does not expire. In this study, we solve the optimal stopping problem of a perpetual American option (both call and put) in discrete time using linear programming duality. Under the assumption that the underlying stock price follows a discrete time and discrete state Markov process, namely a geometric random walk, we formulate the pricing problem as an infinite dimensional linear programming (LP) problem using the excessive-majorant property of the value function. This formulation allows us to solve complementary slackness conditions in closed-form, revealing an optimal stopping strategy which highlights the set of stock-prices where the option should be exercised. The analysis for the call option reveals that such a critical value exists only in some cases, depending on a combination of state-transition probabilities and the economic discount factor (i.e., the prevailing interest rate) whereas it ceases to be an issue for the put.

  12. Northern Hemisphere wintertime variability in a two-level general circulation model. Part II. The maintenance of short and long time-scale disturbances

    SciTech Connect (OSTI)

    Kushnir, Y.; Esbensen, S.K.

    1986-12-01

    The energetics of large-scale disturbances of the wintertime, Northern Hemisphere circulation are studied with the OSU two-level general circulation model. The behavior of simulated eddies with short time-scale (2.5 to 10 days) is found to be consistent with observations and with baroclinic instability theory. Eddies with long time-scales (>10 days) appear to be maintained primarily by high-latitude baroclinic energy conversions. Energy conversions characteristic of barotropic processes are found at jet stream latitudes.

  13. Leadership Development Series Events | Department of Energy

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

    Leadership Development Series Events Leadership Development Series Events The Office of Learning and Workforce Development (OLWD) sponsors these monthly events to provide opportunities for continuing leadership development. These events are hosted at the headquarters office and broadcasted by request to executives at field offices. Presenters are nationally known authors or professional speakers on subjects directly related to leadership, executive development or managing organizations. Benefits

  14. Recovery and Resilience After a Nuclear Power Plant Disaster: A Medical Decision model for Managing an Effective, Timely, and Balanced Response

    SciTech Connect (OSTI)

    Coleman, C. Norman; Blumenthal, Daniel J.

    2013-05-01

    Based on experiences in Tokyo responding to the Fukushima Daiichi nuclear power plant crisis, a real-time, medical decision model is presented by which to make key health-related decisions given the central role of health and medical issues in such disasters. Focus is on response and recovery activities that are safe, timely, effective, and well-organized. This approach empowers on-site decision makers to make interim decisions without undue delay using readily available and high-level scientific, medical, communication, and policy expertise. Key features of this approach include ongoing assessment, consultation, information, and adaption to the changing conditions. This medical decision model presented is compatible with the existing US National Response Framework structure.

  15. Video: FEMP eTraining New Certificate Series | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    describes the FEMP Certificate Series and lists the benefits of taking courses available from the various series topic areas

  16. Downhole delay assembly for blasting with series delay

    DOE Patents [OSTI]

    Ricketts, Thomas E.

    1982-01-01

    A downhole delay assembly is provided which can be placed into a blasthole for initiation of explosive in the blasthole. The downhole delay assembly includes at least two detonating time delay devices in series in order to effect a time delay of longer than about 200 milliseconds in a round of explosions. The downhole delay assembly provides a protective housing to prevent detonation of explosive in the blasthole in response to the detonation of the first detonating time delay device. There is further provided a connection between the first and second time delay devices. The connection is responsive to the detonation of the first detonating time delay device and initiates the second detonating time delay device. A plurality of such downhole delay assemblies are placed downhole in unfragmented formation and are initiated simultaneously for providing a round of explosive expansions. The explosive expansions can be used to form an in situ oil shale retort containing a fragmented permeable mass of formation particles.

  17. UNCLASSIFIED Information Science and Technology Seminar Speaker Series

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

    Information Science and Technology Seminar Speaker Series Joachim M. Buhmann Institute for Machine Learning ETH Zurich Information theory of algorithms: How precisely should we compute in Big Data settings? Wednesday, January 13, 2016 3:00 - 4:00 PM TA-3, Bldg. 1690, Room 102 (CNLS Conference Room) Abstract: Algorithms map input spaces to output spaces where inputs are possibly affected by fluctuations. Beside run time and memory consumption, an algorithm might be characterized by its

  18. Estimation of time to rupture in a fire using 6FIRE, a lumped parameter UF{sub 6} cylinder transient heat transfer/stress analysis model

    SciTech Connect (OSTI)

    Williams, W.R.; Anderson, J.C.

    1995-12-31

    The transportation of UF{sup 6} is subject to regulations requiring the evaluation of packaging under a sequence of hypothetical accident conditions including exposure to a 30-min 800{degree}C (1475{degree}F) fire [10 CFR 71.73(c)(3)]. An issue of continuing interest is whether bare cylinders can withstand such a fire without rupturing. To address this issue, a lumped parameter heat transfer/stress analysis model (6FIRE) has been developed to simulate heating to the point of rupture of a cylinder containing UF{sup 6} when it is exposed to a fire. The model is described, then estimates of time to rupture are presented for various cylinder types, fire temperatures, and fill conditions. An assessment of the quantity of UF{sup 6} released from containment after rupture is also presented. Further documentation of the model is referenced.

  19. Atomistic simulation of laser-pulse surface modification: Predictions of models with various length and time scales

    SciTech Connect (OSTI)

    Starikov, Sergey V. Pisarev, Vasily V.

    2015-04-07

    In this work, the femtosecond laser pulse modification of surface is studied for aluminium (Al) and gold (Au) by use of two-temperature atomistic simulation. The results are obtained for various atomistic models with different scales: from pseudo-one-dimensional to full-scale three-dimensional simulation. The surface modification after laser irradiation can be caused by ablation and melting. For low energy laser pulses, the nanoscale ripples may be induced on a surface by melting without laser ablation. In this case, nanoscale changes of the surface are due to a splash of molten metal under temperature gradient. Laser ablation occurs at a higher pulse energy when a crater is formed on the surface. There are essential differences between Al ablation and Au ablation. In the first step of shock-wave induced ablation, swelling and void formation occur for both metals. However, the simulation of ablation in gold shows an additional athermal type of ablation that is associated with electron pressure relaxation. This type of ablation takes place at the surface layer, at a depth of several nanometers, and does not induce swelling.

  20. A Nuclear Family: Extras - About the Series | Y-12 National Security...

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

    - ... A Nuclear Family: Extras - About the Series The mp4 video format is not supported by this browser. Download video Captions: On Time: 11:49 min. D. Ray Smith, Y-12 historian,...

  1. Climate Change Task Force Webinar Series

    Broader source: Energy.gov [DOE]

    The four-part Climate Change Impacts and Indian Country webinar series provided tribal leaders an opportunity to share their insights, experiences, and ideas with President Obamas State, Local,...

  2. Summer Series 2012 - Conversation with Omar Yaghi

    SciTech Connect (OSTI)

    Omar Yaghi

    2012-07-23

    Jeff Miller, head of Public Affairs, sat down in conversation with Omar Yaghi, director of the Molecular Foundry, in the first of a series of "powerpoint-free" talks on July 11th 2012, at Berkeley Lab.

  3. Summer Series 2012 - Conversation with Omar Yaghi

    ScienceCinema (OSTI)

    Omar Yaghi

    2013-06-24

    Jeff Miller, head of Public Affairs, sat down in conversation with Omar Yaghi, director of the Molecular Foundry, in the first of a series of "powerpoint-free" talks on July 11th 2012, at Berkeley Lab.

  4. Invitation: Commercial Building Envelope Technology Webinar Series

    Broader source: Energy.gov [DOE]

    U.S. DOE’s Better Building Alliance and Oak Ridge National Laboratory (ORNL) are kicking off a new webinar series focused on advancing envelope technologies in commercial buildings. You are invited...

  5. The Manhattan Project National Security History Series

    Office of Environmental Management (EM)

    The Manhattan Project National Security History Series 5 Visit our Manhattan Project web site: http:www.cfo.doe.govme70manhattanindex.htm 5 DOEMA-0002 Revised F. G. Gosling ...

  6. Commercial Building Envelope Technology Webinar Series | Department...

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

    Commercial Building Envelope Technology Webinar Series May 24, 2016 1:00PM to 1:45PM EDT ... Energy Efficiency - Walls. May 24, 1 to 1:45 p.m. EST Energy Efficiency - Roofs. May 31, 1 ...

  7. Tribal Energy and Economic Development Webinar Series

    Broader source: Energy.gov [DOE]

    The DOE Office of Indian Energy Policy and Programs, in partnership with Western Area Power Administration (Western), is pleased to continue its sponsorship of the DOE Tribal Energy and Economic Development Webinar Series for 2016.

  8. Summer Series 2012 - Conversation with Kathy Yelick

    ScienceCinema (OSTI)

    Yelick, Kathy

    2013-06-24

    Jeff Miller, head of Public Affairs, sat down in conversation with Kathy Yelick, Associate Berkeley Lab Director, Computing Sciences, in the second of a series of "powerpoint-free" talks on July 18th 2012, at Berkeley Lab.

  9. Satellite stories featured in Lab lecture series

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

    Satellite stories featured Satellite stories featured in Lab lecture series Space adventures will be featured in the upcoming Frontiers in Science lecture series "Small Satellites on a Shoestring: The LANL Experience." February 14, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new

  10. Uranium-series constraints on radionuclide transport and groundwater flow at the Nopal I uranium deposit, Sierra Pena Blanca, Mexico

    SciTech Connect (OSTI)

    Goldstein, S.J.; Abdel-Fattah, A.I.; Murrell, M.T.; Dobson, P.F.; Norman, D.E.; Amato, R.S.; Nunn, A. J.

    2009-10-01

    Uranium-series data for groundwater samples from the Nopal I uranium ore deposit were obtained to place constraints on radionuclide transport and hydrologic processes for a nuclear waste repository located in fractured, unsaturated volcanic tuff. Decreasing uranium concentrations for wells drilled in 2003 are consistent with a simple physical mixing model that indicates that groundwater velocities are low ({approx}10 m/y). Uranium isotopic constraints, well productivities, and radon systematics also suggest limited groundwater mixing and slow flow in the saturated zone. Uranium isotopic systematics for seepage water collected in the mine adit show a spatial dependence which is consistent with longer water-rock interaction times and higher uranium dissolution inputs at the front adit where the deposit is located. Uranium-series disequilibria measurements for mostly unsaturated zone samples indicate that {sup 230}Th/{sup 238}U activity ratios range from 0.005-0.48 and {sup 226}Ra/{sup 238}U activity ratios range from 0.006-113. {sup 239}Pu/{sup 238}U mass ratios for the saturated zone are <2 x 10{sup -14}, and Pu mobility in the saturated zone is >1000 times lower than the U mobility. Saturated zone mobility decreases in the order {sup 238}U{approx}{sup 226}Ra > {sup 230}Th{approx}{sup 239}Pu. Radium and thorium appear to have higher mobility in the unsaturated zone based on U-series data from fractures and seepage water near the deposit.

  11. Uranium and thorium decay series disequilibria in young volcanic rocks

    SciTech Connect (OSTI)

    Williams, R.W.

    1988-01-01

    Two of the central questions in igneous geochemistry that study of radioactive disequilibria can help to answer are: what are the rates of magma genesis; and what are the timescales of magma separation and transport. In addition to the temporal information that may be extracted from disequilibria data, the {sup 230}Th/{sup 232}Th of a young rock may be used as a tracer of the Th/U ratio of its source region. Measurements were made by isotope dilution alpha-spectrometry of {sup 238}U, {sup 234}U, {sup 230}Th, and {sup 232}Th in 20 subduction related, 3 oceanic intraplate, and 10 continental intraplate volcanics. {sup 210}Pb was measured in all, {sup 226}Ra was measured in about half, and {sup 228}Th was measured in 10 of the most recent samples. Disequilibrium between {sup 228}Th and {sup 232}Th was found only in the Nacarbonatite samples from Oldoinyo Lengai volcano in Tanzania, which is attributable to {sup 228}Ra/{sup 232}Th {approximately} 27 at the time of eruption. These rocks also have {sup 226}Ra/{sup 230}Th > 60. Three Ra-enrichment models are developed which constrain carbonatite magma formation at less than 20 years before eruption. The effects of different partial melting processes on the {sup 238}U decay series are investigated. If mid-ocean ridge basalts are formed by a dynamic melting process, the {sup 230}Th/{sup 232}Th of the basalts provides a minimum estimate of the Th/U ratio of the source region. The {sup 238}U enrichment in arc volcanics is probably the results of metasomatism of the source by fluids derived from the subducting slab, and the {sup 230}Th enrichment observed for other volcanics is probably due to the partial melting process in the absence of U-bearing fluids.

  12. Derivation of a Multiparameter Gamma Model for Analyzing the Residence-Time Distribution Function for Nonideal Flow Systems as an Alternative to the Advection-Dispersion Equation

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

    Embry, Irucka; Roland, Victor; Agbaje, Oluropo; Watson, Valetta; Martin, Marquan; Painter, Roger; Byl, Tom; Sharpe, Lonnie

    2013-01-01

    A new residence-time distribution (RTD) function has been developed and applied to quantitative dye studies as an alternative to the traditional advection-dispersion equation (AdDE). The new method is based on a jointly combined four-parameter gamma probability density function (PDF). The gamma residence-time distribution (RTD) function and its first and second moments are derived from the individual two-parameter gamma distributions of randomly distributed variables, tracer travel distance, and linear velocity, which are based on their relationship with time. The gamma RTD function was used on a steady-state, nonideal system modeled as a plug-flow reactor (PFR) in the laboratory to validate themore » effectiveness of the model. The normalized forms of the gamma RTD and the advection-dispersion equation RTD were compared with the normalized tracer RTD. The normalized gamma RTD had a lower mean-absolute deviation (MAD) (0.16) than the normalized form of the advection-dispersion equation (0.26) when compared to the normalized tracer RTD. The gamma RTD function is tied back to the actual physical site due to its randomly distributed variables. The results validate using the gamma RTD as a suitable alternative to the advection-dispersion equation for quantitative tracer studies of non-ideal flow systems.« less

  13. Simulating Ru L3-Edge X-ray Absorption Spectroscopy with Time-Dependent Density Functional Theory: Model Complexes and Electron Localization in Mixed-Valence Metal Dimers

    SciTech Connect (OSTI)

    Kuiken, Benjamin E. Van; Valiev, Marat; Daifuku, Stephanie L.; Bannan, Caitlin; Strader, Matthew L.; Cho, Hana; Huse, Nils; Schoenlein, Robert W.; Govind, Niranjan; Khalil, Munira

    2013-04-26

    Ruthenium L3-edge X-ray absorption (XA) spectroscopy probes unoccupied 4d orbitals of the metal atom and is increasingly being used to investigate the local electronic structure in ground and excited electronic states of Ru complexes. The simultaneous development of computational tools for simulating Ru L3-edge spectra is crucial for interpreting the spectral features at a molecular level. This study demonstrates that time-dependent density functional theory (TDDFT) is a viable and predictive tool for simulating ruthenium L3-edge XA spectroscopy. We systematically investigate the effects of exchange correlation functional and implicit and explicit solvent interactions on a series of RuII and RuIII complexes in their ground and electronic excited states. The TDDFT simulations reproduce all of the experimentally observed features in Ru L3-edge XA spectra within the experimental resolution (0.4 eV). Our simulations identify ligand-specific charge transfer features in complicated Ru L3-edge spectra of [Ru(CN)6]4- and RuII polypyridyl complexes illustrating the advantage of using TDDFT in complex systems. We conclude that the B3LYP functional most accurately predicts the transition energies of charge transfer features in these systems. We use our TDDFT approach to simulate experimental Ru L3-edge XA spectra of transition metal mixed-valence dimers of the form [(NC)5MII-CN-RuIII(NH3)5] (where M = Fe or Ru) dissolved in water. Our study determines the spectral signatures of electron delocalization in Ru L3-edge XA spectra. We find that the inclusion of explicit solvent molecules is necessary for reproducing the spectral features and the experimentally determined valencies in these mixed-valence complexes. This study validates the use of TDDFT for simulating Ru 2p excitations using popular quantum chemistry codes and providing a powerful interpretive tool for equilibrium and ultrafast Ru L3-edge XA spectroscopy.

  14. Two-Dimensional Modeling of Time-Varying Hydrodynamics and Juvenile Chinook Salmon Habitat in the Hanford Reach of the Columbia River

    SciTech Connect (OSTI)

    Perkins, William A.; Richmond, Marshall C.; McMichael, Geoffrey A.

    2007-10-10

    The Hanford Reach is the only remaining unimpounded reach of the Columbia River in the United States above Bonneville Dam. Discharge in the Hanford Reach is regulated by several dams and is often subject to rapid changes. Sharp flow reductions have led to the stranding or entrapment, and subsequent mortality, of juvenile chinook salmon (Oncorynchus tshawytscha) and other important fish species within the Hanford Reach. A multi-block two-dimensional depth-averaged hydrodynamic model was used to simulate time-varying river velocity and stage in a 37~km portion of the Hanford Reach. Simulation results were used to estimate time-varying juvenile chinook salmon habitat area, and the part of that habitat affected by discharge fluctuations. Affected habitat area estimates were made for the chinook salmon rearing period of four years. These estimates were used, along with other important factors, to establish a statistical relationship between discharge fluctuation and juvenile chinook salmon mortality.

  15. A novel method for modeling the neutron time of flight detector response in current mode to inertial confinement fusion experiments (invited)

    SciTech Connect (OSTI)

    Nelson, A. J.; Cooper, G. W. [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Ruiz, C. L.; Chandler, G. A.; Fehl, D. L.; Hahn, K. D.; Leeper, R. J.; Smelser, R.; Torres, J. A. [Sandia National Laboratories, Albuquerque, New Mexico 87185-1196 (United States)

    2012-10-15

    A novel method for modeling the neutron time of flight (nTOF) detector response in current mode for inertial confinement fusion experiments has been applied to the on-axis nTOF detectors located in the basement of the Z-Facility. It will be shown that this method can identify sources of neutron scattering, and is useful for predicting detector responses in future experimental configurations, and for identifying potential sources of neutron scattering when experimental set-ups change. This method can also provide insight on how much broadening neutron scattering contributes to the primary signals, which is then subtracted from them. Detector time responses are deconvolved from the signals, allowing a transformation from dN/dt to dN/dE, extracting neutron spectra at each detector location; these spectra are proportional to the absolute yield.

  16. A stochastically forced time delay solar dynamo model: Self-consistent recovery from a maunder-like grand minimum necessitates a mean-field alpha effect

    SciTech Connect (OSTI)

    Hazra, Soumitra; Nandy, Dibyendu; Passos, Dário E-mail: dariopassos@ist.utl.pt

    2014-07-01

    Fluctuations in the Sun's magnetic activity, including episodes of grand minima such as the Maunder minimum have important consequences for space and planetary environments. However, the underlying dynamics of such extreme fluctuations remain ill-understood. Here, we use a novel mathematical model based on stochastically forced, non-linear delay differential equations to study solar cycle fluctuations in which time delays capture the physics of magnetic flux transport between spatially segregated dynamo source regions in the solar interior. Using this model, we explicitly demonstrate that the Babcock-Leighton poloidal field source based on dispersal of tilted bipolar sunspot flux, alone, cannot recover the sunspot cycle from a grand minimum. We find that an additional poloidal field source effective on weak fields—e.g., the mean-field α effect driven by helical turbulence—is necessary for self-consistent recovery of the sunspot cycle from grand minima episodes.

  17. Sequentially Executed Model Evaluation Framework

    SciTech Connect (OSTI)

    2014-02-14

    Provides a message passing framework between generic input, model and output drivers, and specifies an API for developing such drivers. Also provides batch and real-time controllers which step the model and 1/0 through the time domain (or other discrete domain), and sample 1/0 drivers. This is a Framework library framework, and does not, itself, solve any problems or execute any modelling. The SeMe framework aids in development of models which operate on sequential information, such as time-series, where evaluation is based on prior results combined with new data for this iteration. Ha) applications in quality monitoring, and was developed as part of the CANARY-EDS software, where real-time water quality data is being analyzed

  18. Sequentially Executed Model Evaluation Framework

    Energy Science and Technology Software Center (OSTI)

    2014-02-14

    Provides a message passing framework between generic input, model and output drivers, and specifies an API for developing such drivers. Also provides batch and real-time controllers which step the model and 1/0 through the time domain (or other discrete domain), and sample 1/0 drivers. This is a Framework library framework, and does not, itself, solve any problems or execute any modelling. The SeMe framework aids in development of models which operate on sequential information, suchmore » as time-series, where evaluation is based on prior results combined with new data for this iteration. Ha) applications in quality monitoring, and was developed as part of the CANARY-EDS software, where real-time water quality data is being analyzed« less

  19. Sequentially Executed Model Evaluation Framework

    Energy Science and Technology Software Center (OSTI)

    2015-10-20

    Provides a message passing framework between generic input, model and output drivers, and specifies an API for developing such drivers. Also provides batch and real-time controllers which step the model and I/O through the time domain (or other discrete domain), and sample I/O drivers. This is a library framework, and does not, itself, solve any problems or execute any modeling. The SeMe framework aids in development of models which operate on sequential information, such asmore » time-series, where evaluation is based on prior results combined with new data for this iteration. Has applications in quality monitoring, and was developed as part of the CANARY-EDS software, where real-time water quality data is being analyzed for anomalies.« less

  20. Communication: Satisfying fermionic statistics in the modeling of open time-dependent quantum systems with one-electron reduced density matrices

    SciTech Connect (OSTI)

    Head-Marsden, Kade; Mazziotti, David A.

    2015-02-07

    For an open, time-dependent quantum system, Lindblad derived the most general modification of the quantum Liouville equation in the Markovian approximation that models environmental effects while preserving the non-negativity of the system’s density matrix. While Lindblad’s modification is correct for N-electron density matrices, solution of the Liouville equation with a Lindblad operator causes the one-electron reduced density matrix (1-RDM) to violate the Pauli exclusion principle. Consequently, after a short time, the 1-RDM is not representable by an ensemble N-electron density matrix (not ensemble N-representable). In this communication, we derive the necessary and sufficient constraints on the Lindbladian matrix within the Lindblad operator to ensure that the 1-RDM remains N-representable for all time. The theory is illustrated by considering the relaxation of an excitation in several molecules F{sub 2}, N{sub 2}, CO, and BeH{sub 2} subject to environmental noise.

  1. Series connected OLED structure and fabrication method

    DOE Patents [OSTI]

    Foust, Donald Franklin; Balch, Ernest Wayne; Duggal, Anil Raj; Heller, Christian Maria; Guida, Renato; Nealon, William Francis; Faircloth, Tami Janene

    2006-05-23

    A light emitting device comprises a plurality of organic light emitting diode (OLED) modules. The OLED modules are arranged into a series group where the individual OLED modules are electrically connected in series. The device is configured to be coupled to a power supply. A display is also provided. The display includes a plurality of OLED modules arranged to depict a shape selected from the group consisting of at least one letter, at least one number, at least one image, and a combination thereof.

  2. Café Scientifique New Mexico series

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

    Wallace to bring earthquakes to life for Café Scientifique New Mexico series September 13, 2012 School-age teens to learn about and discuss a decade of great earthquakes Seismic expert Terry Wallace, principal associate director for Global Security (PADGS), will present an exciting look at earthquakes for Northern New Mexico high-school- age students as part of the Café Scientifique New Mexico program. The fun, free conversation series provides a way for teens to explore the latest ideas in

  3. A Spatially Based Area–Time Inundation Index Model Developed to Assess Habitat Opportunity in Tidal–Fluvial Wetlands and Restoration Sites

    SciTech Connect (OSTI)

    Coleman, Andre M.; Diefenderfer, Heida L.; Ward, Duane L.; Borde, Amy B.

    2015-09-01

    The hydrodynamics of tidal wetland areas in the lower Columbia River floodplain and estuary directly affect habitat opportunity for endangered salmonid fishes. Physical and biological structures and functions in the system are directly affected by inundation patterns influenced by tidal cycles, hydropower operations, river discharge, upriver water withdrawals, climate, and physical barriers such as dikes, culverts, and tide gates. Ongoing ecosystem restoration efforts are intended to increase the opportunity for salmon to access beneficial habitats by hydrologically reconnecting main-stem river channels and diked areas within the historical floodplain. To address the need to evaluate habitat opportunity, a geographic information system-based Area-Time Inundation Index Model (ATIIM) was developed. The ATIIM integrates in situ or modeled hourly water-surface elevation (WSE) data and advanced terrain processing of high-resolution elevation data. The ATIIM uses a spatially based wetted-area algorithm to determine site average bankfull elevation, two- and three-dimensional inundation extent, and other site metrics. Hydrological process metrics such as inundation frequency, duration, maximum area, and maximum frequency area can inform evaluation of proposed restoration sites; e.g., determine trade-offs between WSE and habitat opportunity, contrast alternative restoration designs, predict impacts of altered flow regimes, and estimate nutrient and biomass fluxes. In an adaptive management framework, this model can be used to provide standardized site comparisons and effectiveness monitoring of changes in the developmental trajectories of restoration sites. Results are presented for 11 wetlands representative of tidal marshes, tidal forested wetlands, and restoration sites.

  4. FEMP Releases New Water Management Course and Series | Department...

    Office of Environmental Management (EM)

    Water Management Course and Series FEMP Releases New Water Management Course and Series October 12, 2015 - 2:27pm Addthis FEMP Releases New Water Management Course and Series The ...

  5. SEE Action Series: Local Strategies for Whole-Building Energy...

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

    SEE Action Series: Local Strategies for Whole-Building Energy Savings SEE Action Series: Local Strategies for Whole-Building Energy Savings This presentation provides information ...

  6. Building America Best Practices Series, Volume 13 - Energy Performance...

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

    Series, Volume 13 - Energy Performance Techniques and Technologies: Perserving Historic Homes Building America Best Practices Series, Volume 13 - Energy Performance Techniques and ...

  7. Building America Best Practices Series: Volume 12. EnergyRenovations...

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

    Series: Volume 12. Energy Renovations-Insulation: A Guide for Contractors to Share With Homeowners Building America Best Practices Series: Volume 12. Energy Renovations-Insulation: ...

  8. Pennsylvania: New Series of Windows Has Potential to Save Energy...

    Office of Environmental Management (EM)

    New Series of Windows Has Potential to Save Energy for Commercial Buildings Pennsylvania: New Series of Windows Has Potential to Save Energy for Commercial Buildings March 6, 2014...

  9. Tribal Energy and Economic Development Webinar Series | Department...

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

    Training Tribal Energy and Economic Development Webinar Series Tribal Energy and Economic Development Webinar Series The DOE Office of Indian Energy Policy and Programs, in...

  10. DOE Tribal Renewable Energy Webinar Series 2015 Flier

    Broader source: Energy.gov (indexed) [DOE]

    (Western), is pleased to continue its sponsorship of the DOE Tribal Renewable Energy Webinar Series for 2015. The webinar series is part of DOE's coordinated efforts to...

  11. Focus Series: Program Finds Community "Readiness" Is the Key...

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

    Program Finds Community "Readiness" Is the Key to More Retrofits Focus Series: Program Finds Community "Readiness" Is the Key to More Retrofits Focus Series: Program Finds ...

  12. A Series of Highly Stable Mesoporous Metalloporphyrin Fe-MOFs...

    Office of Scientific and Technical Information (OSTI)

    A Series of Highly Stable Mesoporous Metalloporphyrin Fe-MOFs Citation Details In-Document Search Title: A Series of Highly Stable Mesoporous Metalloporphyrin Fe-MOFs Authors: ...

  13. MIE Regional Climate Change Impact Webinar Series: Hawaii & Pacific...

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

    MIE Regional Climate Change Impact Webinar Series: Hawaii & Pacific Islands MIE Regional Climate Change Impact Webinar Series: Hawaii & Pacific Islands November 5, 2015 1:00PM to...

  14. Climate Investment Funds Webinar Series | Open Energy Information

    Open Energy Info (EERE)

    Investment Funds Webinar Series Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Climate Investment Funds Webinar Series AgencyCompany Organization: Asian Development...

  15. Live: DOE Cyber Distinguished Speaker Series | Department of...

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

    Live: DOE Cyber Distinguished Speaker Series Live: DOE Cyber Distinguished Speaker Series Live streaming video by Ustream HOW ACADEMIC INSTITUIONS ARE MEETING TODAY'S CYBER ...

  16. Philippines: Asia Pacific energy series: Country report (Technical...

    Office of Scientific and Technical Information (OSTI)

    Philippines: Asia Pacific energy series: Country report Citation Details In-Document Search Title: Philippines: Asia Pacific energy series: Country report You are accessing a ...

  17. Green Racing Series Revs Engines with Renewable Fuel from INEOS...

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

    Racing Series Revs Engines with Renewable Fuel from INEOS Bio Green Racing Series Revs ... races. | Photo by Natalie Committee, Energy Department A racecar heads into the pits ...

  18. Physics Meets Biology (LBNL Summer Lecture Series)

    ScienceCinema (OSTI)

    Chu, Steve [Director, LBNL

    2011-04-28

    Summer Lecture Series 2006: If scientists could take advantage of the awesomely complex and beautiful functioning of biologys natural molecular machines, their potential for application in many disciplines would be incalculable. Nobel Laureate and Director of the Lawrence Berkeley National Laboratory Steve Chu explores Possible solutions to global warming and its consequences.

  19. Biomass thermal conversion research at SERI

    SciTech Connect (OSTI)

    Milne, T. A.; Desrosiers, R. E.; Reed, T. B.

    1980-09-01

    SERI's involvement in the thermochemical conversion of biomass to fuels and chemicals is reviewed. The scope and activities of the Biomass Thermal Conversion and Exploratory Branch are reviewed. The current status and future plans for three tasks are presented: (1) Pyrolysis Mechanisms; (2) High Pressure O/sub 2/ Gasifier; and (3) Gasification Test Facility.

  20. Invitation: Commercial Building Envelope Technology Webinar Series...

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

    Technology Webinar Series May 17, 2016 1:00PM to 1:45PM EDT Oak Ridge National Lab logo. ... You are invited to the first webinar on Tuesday, May 17, from 1 to 1:45 p.m. (EST). This ...

  1. Space Radiation and Cataracts (LBNL Summer Lecture Series)

    ScienceCinema (OSTI)

    Blakely, Eleanor

    2011-04-28

    Summer Lecture Series 2009: Eleanor Blakely, radiation biologist of the Life Sciences Division at Lawrence Berkeley National Laboratory, has been a scientist at Berkeley Lab since 1975. She is studying the effect of radiation on cataracts which concerns not only cancer patients, but also astronauts. As astronauts spend increasingly longer time in space, the effects of cosmic radiation exposure will become an increasingly important health issue- yet there is little human data on these effects. Blakely reviews this emerging field and the contributions made at Berkeley Lab

  2. Laser processing technique for fabricating series-connected and tandem junction series-connected solar cells into a solar battery

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1981-01-01

    A method of fabricating series-connected and tandem junction series-connected solar cells into a solar battery with laser scribing.

  3. Jefferson Lab Announces Fall Science Series Event Nov. 23 | Jefferson Lab

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

    Announces Fall Science Series Event Nov. 23 Jefferson Lab Announces Fall Science Series Event Nov. 23 Speaker examines timely Thanksgiving topic: food toxins & how to avoid them October 27, 2004 On Tuesday, Nov. 23, at Jefferson Lab - just before Thanksgiving - join Kristen Kulp, a cancer research scientist with the Biology and Biotechnology Research Program at Lawrence Livermore National Laboratory, as she discusses "What's for Dinner? Avoiding Toxins Lurking in Your Food." Kulp

  4. Monitoring CO 2 sequestration into deep saline aquifer and associated salt intrusion using coupled multiphase flow modeling and time lapse electrical resistivity tomography

    SciTech Connect (OSTI)

    Chuan Lu; CHI Zhang; Hai Hanag; Timothy C. Johnson

    2014-04-01

    Successful geological storage and sequestration of carbon dioxide (CO2) require efficient monitoring of the migration of CO2 plume during and after large-scale injection in order to verify the containment of the injected CO2 within the target formation and to evaluate potential leakage risk. Field studies have shown that surface and cross-borehole electrical resistivity tomography (ERT) can be a useful tool in imaging and characterizing solute transport in heterogeneous subsurface. In this synthetic study, we have coupled a 3-D multiphase flow model with a parallel 3-D time-lapse ERT inversion code to explore the feasibility of using time-lapse ERT for simultaneously monitoring the migration of CO2 plume in deep saline formation and potential brine intrusion into shallow fresh water aquifer. Direct comparisons of the inverted CO2 plumes resulting from ERT with multiphase flow simulation results indicate the ERT could be used to delineate the migration of CO2 plume. Detailed comparisons on the locations, sizes and shapes of CO2 plume and intruded brine plumes suggest that ERT inversion tends to underestimate the area review of the CO2 plume, but overestimate the thickness and total volume of the CO2 plume. The total volume of intruded brine plumes is overestimated as well. However, all discrepancies remain within reasonable ranges. Our study suggests that time-lapse ERT is a useful monitoring tool in characterizing the movement of injected CO2 into deep saline aquifer and detecting potential brine intrusion under large-scale field injection conditions.

  5. Monitoring CO2 Storage at Cranfield, Mississippi with Time-Lapse Offset VSP – Using Integration and Modeling to Reduce Uncertainty

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

    Daley, Thomas M.; Hendrickson, Joel; Queen, John H.

    2014-12-31

    corridor stacks but, due to relatively lower S/N, the results were less consistent and more sensitive to processing and therefore are not presented. We examined the overall time-lapse repeatability of the OVSP data using three methods, the NRMS and Predictability (Pred) measures of Kragh and Christie (2002) and the signal-to-distortion ratio (SDR) method of Cantillo (2011). Because time-lapse noise was comparable to the observed change, multiple methods were used to analyze data reliability. The reflections from the top and base reservoir were identified on the corridor stacks by correlation with a synthetic response generated from the well logs. A consistent change in the corridor stack amplitudes from pre- to post-CO2 injection was found for both the top and base reservoir reflections on all ten shot locations analyzed. In addition to the well-log synthetic response, a finite-difference elastic wave propagation model was built based on rock/fluid properties obtained from well logs, with CO2 induced changes guided by time-lapse crosswell seismic tomography (Ajo-Franklin, et al., 2013) acquired at the DAS site. Time-lapse seismic tomography indicated that two reservoir zones were affected by the flood. The modeling established that interpretation of the VSP trough and peak event amplitudes as reflectivity from the top and bottom of reservoir is appropriate even with possible tuning effects. Importantly, this top/base change gives confidence in an interpretation that these changes arise from within the reservoir, not from bounding lithology. The modeled time-lapse change and the observed field data change from 10 shotpoints are in agreement for both magnitude and polarity of amplitude change for top and base of reservoir. Therefore, we conclude the stored CO2 has been successfully detected and, furthermore, the observed seismic reflection change can be applied to Cranfield’s 4D surface seismic for spatially delineating the CO2/brine interface.« less

  6. Monitoring CO2 Storage at Cranfield, Mississippi with Time-Lapse Offset VSP Using Integration and Modeling to Reduce Uncertainty

    SciTech Connect (OSTI)

    Daley, Thomas M.; Hendrickson, Joel; Queen, John H.

    2014-12-31

    (used to map the plume) was similar in magnitude to the corridor stacks but, due to relatively lower S/N, the results were less consistent and more sensitive to processing and therefore are not presented. We examined the overall time-lapse repeatability of the OVSP data using three methods, the NRMS and Predictability (Pred) measures of Kragh and Christie (2002) and the signal-to-distortion ratio (SDR) method of Cantillo (2011). Because time-lapse noise was comparable to the observed change, multiple methods were used to analyze data reliability. The reflections from the top and base reservoir were identified on the corridor stacks by correlation with a synthetic response generated from the well logs. A consistent change in the corridor stack amplitudes from pre- to post-CO2 injection was found for both the top and base reservoir reflections on all ten shot locations analyzed. In addition to the well-log synthetic response, a finite-difference elastic wave propagation model was built based on rock/fluid properties obtained from well logs, with CO2 induced changes guided by time-lapse crosswell seismic tomography (Ajo-Franklin, et al., 2013) acquired at the DAS site. Time-lapse seismic tomography indicated that two reservoir zones were affected by the flood. The modeling established that interpretation of the VSP trough and peak event amplitudes as reflectivity from the top and bottom of reservoir is appropriate even with possible tuning effects. Importantly, this top/base change gives confidence in an interpretation that these changes arise from within the reservoir, not from bounding lithology. The modeled time-lapse change and the observed field data change from 10 shotpoints are in agreement for both magnitude and polarity of amplitude change for top and base of reservoir. Therefore, we conclude the stored CO2 has been successfully detected and, furthermore, the observed seismic reflection change can

  7. TH-E-BRF-05: Comparison of Survival-Time Prediction Models After Radiotherapy for High-Grade Glioma Patients Based On Clinical and DVH Features

    SciTech Connect (OSTI)

    Magome, T; Haga, A; Igaki, H; Sekiya, N; Masutani, Y; Sakumi, A; Mukasa, A; Nakagawa, K

    2014-06-15

    Purpose: Although many outcome prediction models based on dose-volume information have been proposed, it is well known that the prognosis may be affected also by multiple clinical factors. The purpose of this study is to predict the survival time after radiotherapy for high-grade glioma patients based on features including clinical and dose-volume histogram (DVH) information. Methods: A total of 35 patients with high-grade glioma (oligodendroglioma: 2, anaplastic astrocytoma: 3, glioblastoma: 30) were selected in this study. All patients were treated with prescribed dose of 30–80 Gy after surgical resection or biopsy from 2006 to 2013 at The University of Tokyo Hospital. All cases were randomly separated into training dataset (30 cases) and test dataset (5 cases). The survival time after radiotherapy was predicted based on a multiple linear regression analysis and artificial neural network (ANN) by using 204 candidate features. The candidate features included the 12 clinical features (tumor location, extent of surgical resection, treatment duration of radiotherapy, etc.), and the 192 DVH features (maximum dose, minimum dose, D95, V60, etc.). The effective features for the prediction were selected according to a step-wise method by using 30 training cases. The prediction accuracy was evaluated by a coefficient of determination (R{sup 2}) between the predicted and actual survival time for the training and test dataset. Results: In the multiple regression analysis, the value of R{sup 2} between the predicted and actual survival time was 0.460 for the training dataset and 0.375 for the test dataset. On the other hand, in the ANN analysis, the value of R{sup 2} was 0.806 for the training dataset and 0.811 for the test dataset. Conclusion: Although a large number of patients would be needed for more accurate and robust prediction, our preliminary Result showed the potential to predict the outcome in the patients with high-grade glioma. This work was partly supported by

  8. UNCLASSIFIED Institute for Materials Science Lecture Series

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

    Lecture Series Dr Roger D Doherty M.A. D. Phil., Fellow TMS Emeritus Professor of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania Solute Enhanced Strain Hardening of Aluminum Alloys for Higher Strength / Toughness Combinations Wednesday, May 6, 2015 1:15 - 2:15 PM TA-03, Bldg. 1698, Room A103 (MSL Auditorium) Abstract: When the yield strength of metallic alloys is increased the fracture toughness almost always falls. By use of a plot of bond strength normalized

  9. UNCLASSIFIED Institute for Materials Science Seminar Series

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

    Series Dr. Sergey Pershoguba Nordic Institute for Theoretical Physics (NORDITA) Postdoctoral Fellow Skyrmion-induced Bound States in a Superconductor Wednesday, January 20, 2016 11:00 - Noon IMS/MPA Conference Room, TA-3, Bldg 32, Rm 134 Abstract: We consider a superconductor proximity coupled to a two-dimensional ferromagnetic film with a skyrmion texture. We predict the skyrmion bound states (SBS) that are induced in the superconductor, similar to the well-known Yu- Shiba-Rusinov (YSR) states.

  10. UNCLASSIFIED Los Alamos Astrophysics Distinguished Seminar Series

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

    Los Alamos Astrophysics Distinguished Seminar Series Ryan Miranda Cornell University Sustained Dust Asymmetries At Dead Zone Edges in Protoplanetary Disks Thursday, July 21, 2016 2:00 PM - 3:00 PM T-DO Conf Room (TA-03, Building 123, Room 121) Abstract. Protoplanetary disks, consisting of gas and dust in orbit around a newly formed star, are the birthplaces of planetary systems. Several observations of transition disks, a class of protoplanetary disks in which the first stages of planet