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1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet (open access)

1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet

This report is a descriptive summary of the simulation of a free- electron laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet
Date: April 1, 2013
Creator: Shinn, Michelle D. & Benson, Stephen V.
System: The UNT Digital Library
2013 GASEOUS IONS GORDON RESEARCH CONFERENCE, FEBRUARY 24 - MARCH 1, 2013 (open access)

2013 GASEOUS IONS GORDON RESEARCH CONFERENCE, FEBRUARY 24 - MARCH 1, 2013

The Gaseous Ions: Structures, Energetics and Reactions Gordon Research Conference will focus on ions and their interactions with molecules, surfaces, electrons, and light. The long-standing goal of our community is to develop new strategies for capturing complex molecular architectures as gas phase ions where they can be isolated, characterized and manipulated with great sensitivity. Emergent areas of interest include catalytic mechanisms, cryogenic processing of ions extracted from solution, ion fragmentation mechanisms, and new methods for ion formation and structural characterization. The conference will cover theoretical and experimental advances on systems ranging from model studies at the molecular scale to preparation of nanomaterials and characterization of large biological molecules.
Date: March 1, 2013
Creator: Williams, Evan
System: The UNT Digital Library
Accounting for the Variation of Driver Aggression in the Simulation of Conventional and Advanced Vehicles (open access)

Accounting for the Variation of Driver Aggression in the Simulation of Conventional and Advanced Vehicles

Hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles offer the potential to reduce both oil imports and greenhouse gases, as well as to offer a financial benefit to the driver. However, assessing these potential benefits is complicated by several factors, including the driving habits of the operator. We focus on driver aggression, i.e., the level of acceleration and velocity characteristic of travel, to (1) assess its variation within large, real-world drive datasets, (2) quantify its effect on both vehicle efficiency and economics for multiple vehicle types, (3) compare these results to those of standard drive cycles commonly used in the industry, and (4) create a representative drive cycle for future analyses where standard drive cycles are lacking.
Date: January 1, 2013
Creator: Neubauer, J. & Wood, E.
System: The UNT Digital Library
Accounting for the Variation of Driver Aggression in the Simulation of Conventional and Advanced Vehicles: Preprint (open access)

Accounting for the Variation of Driver Aggression in the Simulation of Conventional and Advanced Vehicles: Preprint

Hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles offer the potential to reduce both oil imports and greenhouse gases, as well as to offer a financial benefit to the driver. However, assessing these potential benefits is complicated by several factors, including the driving habits of the operator. We focus on driver aggression, i.e., the level of acceleration and velocity characteristic of travel, to (1) assess its variation within large, real-world drive datasets, (2) quantify its effect on both vehicle efficiency and economics for multiple vehicle types, (3) compare these results to those of standard drive cycles commonly used in the industry, and (4) create a representative drive cycle for future analyses where standard drive cycles are lacking.
Date: March 1, 2013
Creator: Neubauer, J. & Wood, E.
System: The UNT Digital Library
Acquiring Impedance Spectra From Diode-Coupled Primary Batteries to Determine Health and State of Charge (open access)

Acquiring Impedance Spectra From Diode-Coupled Primary Batteries to Determine Health and State of Charge

The U.S. Army uses BA5590 Lithium Sulfur Dioxide p
Date: March 1, 2013
Creator: Morrison, John L.; Christophersen, Jon P. & Morrison, William H.
System: The UNT Digital Library
Adaptive Sampling Algorithms for Probabilistic Risk Assessment of Nuclear Simulations (open access)

Adaptive Sampling Algorithms for Probabilistic Risk Assessment of Nuclear Simulations

Nuclear simulations are often computationally expensive, time-consuming, and high-dimensional with respect to the number of input parameters. Thus exploring the space of all possible simulation outcomes is infeasible using finite computing resources. During simulation-based probabilistic risk analysis, it is important to discover the relationship between a potentially large number of input parameters and the output of a simulation using as few simulation trials as possible. This is a typical context for performing adaptive sampling where a few observations are obtained from the simulation, a surrogate model is built to represent the simulation space, and new samples are selected based on the model constructed. The surrogate model is then updated based on the simulation results of the sampled points. In this way, we attempt to gain the most information possible with a small number of carefully selected sampled points, limiting the number of expensive trials needed to understand features of the simulation space. We analyze the specific use case of identifying the limit surface, i.e., the boundaries in the simulation space between system failure and system success. In this study, we explore several techniques for adaptively sampling the parameter space in order to reconstruct the limit surface. We focus on several …
Date: September 1, 2013
Creator: Mandelli, Diego; Maljovec, Dan; Wang, Bei; Pascucci, Valerio & Bremer, Peer-Timo
System: The UNT Digital Library
Additions to the ICSBEP and IRPhEP Handbooks since NCSD 2009 (open access)

Additions to the ICSBEP and IRPhEP Handbooks since NCSD 2009

High-quality integral benchmark experiments have always been a priority for criticality safety. However, interest in integral benchmark data is increasing as efforts to quantify and reduce calculational uncertainties accelerate to meet the demands of future criticality safety needs to support next generation reactor and advanced fuel cycle concepts. The importance of drawing upon existing benchmark data is becoming more apparent because of dwindling availability of critical facilities worldwide and the high cost of performing new experiments. Integral benchmark data from the International Handbook of Evaluated Criticality Safety Benchmark Experiments and the International Handbook of Reactor Physics Benchmark Experiments are widely used. Significant Benchmark data have been added to those two handbooks since the last Nuclear Criticality Safety Division Topical Meeting in Richland, Washington (September 2009). This paper highlights those additions.
Date: October 1, 2013
Creator: Bess, John D.; Briggs, J. Blair; Gulliford, Jim & Hill, Ian
System: The UNT Digital Library
AdS/QCD, Light-Front Holography, and Color Confinement (open access)

AdS/QCD, Light-Front Holography, and Color Confinement

This report talks about the AdS/QCD, Light-Front Holography, and Color Confinement
Date: February 1, 2013
Creator: Brodsky, Stanley J. & Teramond, Guy F. de
System: The UNT Digital Library
Advance in MEIC cooling studies (open access)

Advance in MEIC cooling studies

Cooling of ion beams is essential for achieving a high luminosity for MEIC at Jefferson Lab. In this paper, we present the design concept of the electron cooling system for MEIC. In the design, two facilities are required for supporting a multi-staged cooling scheme; one is a 2 MeV DC cooler in the ion pre-booster; the other is a high electron energy (up to 55 MeV) ERL-circulator cooler in the collider ring. The simulation studies of beam dynamics in an ERL-circulator cooler are summarized and followed by a report on technology development for this cooler. We also discuss two proposed experiments for demonstrating high energy cooling with a bunched electron beam and the ERL-circulator cooler.
Date: June 1, 2013
Creator: Zhang, Yuhong; Derbenev, Ya.; Douglas, D.; Hutton, A.; Kimber, A.; Li, R. et al.
System: The UNT Digital Library
Advanced Electron Microscopic Techniques Applied t (open access)

Advanced Electron Microscopic Techniques Applied t

Preliminary electron microscopy of coated fuel par
Date: October 1, 2013
Creator: van Rooyen, I. J.; Wu, Y. Q.; Trowbridge, T. L.; Lillo, T. M. & Madden, J. M.
System: The UNT Digital Library
Advanced in-Pile Instrumentation for Materials Tes (open access)

Advanced in-Pile Instrumentation for Materials Tes

The US Department of Energy sponsors the Advanced
Date: June 1, 2013
Creator: Rempe, Joy L.; Knudson, Darrell L.; Daw, Joshua E.; Unruh, T. C.; Chase, B. M.; Davis, K. L. et al.
System: The UNT Digital Library
Advanced Photovoltaic Inverter Functionality using 500 kW Power Hardware-in-Loop Complete System Laboratory Testing: Preprint (open access)

Advanced Photovoltaic Inverter Functionality using 500 kW Power Hardware-in-Loop Complete System Laboratory Testing: Preprint

With the increasing penetration of distribution connected photovoltaic (PV) systems, more and more PV developers and utilities are interested in easing future PV interconnection concerns by mitigating some of the impacts of PV integration using advanced PV inverter controls and functions. This paper describes the testing of a 500 kW PV inverter using Power Hardware-in-Loop (PHIL) testing techniques. The test setup is described and the results from testing the inverter in advanced functionality modes, not commonly used in currently interconnected PV systems, are presented. PV inverter operation under PHIL evaluation that emulated both the DC PV array connection and the AC distribution level grid connection are shown for constant power factor (PF) and constant reactive power (VAr) control modes. The evaluation of these modes was completed under varying degrees of modeled PV variability.
Date: January 1, 2013
Creator: Mather, B. A.; Kromer, M. A. & Casey, L.
System: The UNT Digital Library
Advanced Platform for Development and Evaluation of Grid Interconnection Systems Using Hardware-in-the-Loop: Part III -- Grid Interconnection System Evaluator: Preprint (open access)

Advanced Platform for Development and Evaluation of Grid Interconnection Systems Using Hardware-in-the-Loop: Part III -- Grid Interconnection System Evaluator: Preprint

This paper, presented at the IEEE Green Technologies Conference 2013, describes a Grid Interconnection System Evaluator (GISE) that leverages hardware-in-the-loop (HIL) simulation techniques to rapidly evaluate the grid interconnection standard conformance of an ICS according to the procedures in IEEE Std 1547.1 (TM). The architecture and test sequencing of this evaluation tool, along with a set of representative ICS test results from three different photovoltaic (PV) inverters, are presented. The GISE adds to the National Renewable Energy Laboratory's (NREL) evaluation platform that now allows for rapid development of ICS control algorithms using controller HIL (CHIL) techniques, the ability to test the dc input characteristics of PV-based ICSs through the use of a PV simulator capable of simulating real-world dynamics using power HIL (PHIL), and evaluation of ICS grid interconnection conformance.
Date: January 1, 2013
Creator: Lundstrom, B.; Shirazi, M.; Coddington, M. & Kroposki, B.
System: The UNT Digital Library
Advanced Platform for Development and Evaluation of Grid Interconnection Systems Using Hardware-in-the-Loop (Poster) (open access)

Advanced Platform for Development and Evaluation of Grid Interconnection Systems Using Hardware-in-the-Loop (Poster)

This poster describes a Grid Interconnection System Evaluator (GISE) that leverages hardware-in-the-loop (HIL) simulation techniques to rapidly evaluate the grid interconnection standard conformance of an ICS according to the procedures in IEEE Std 1547.1TM. The architecture and test sequencing of this evaluation tool, along with a set of representative ICS test results from three different photovoltaic (PV) inverters, are presented. The GISE adds to the National Renewable Energy Laboratory's (NREL) evaluation platform that now allows for rapid development of ICS control algorithms using controller HIL (CHIL) techniques, the ability to test the dc input characteristics of PV-based ICSs through the use of a PV simulator capable of simulating real-world dynamics using power HIL (PHIL), and evaluation of ICS grid interconnection conformance.
Date: February 1, 2013
Creator: Lundstrom, B.; Shirazi, M. & Coddington, M.
System: The UNT Digital Library
Advanced Test Reactor National Scientific User Facility: Addressing advanced nuclear materials research (open access)

Advanced Test Reactor National Scientific User Facility: Addressing advanced nuclear materials research

The Advanced Test Reactor National Scientific User Facility (ATR NSUF), based at the Idaho National Laboratory in the United States, is supporting Department of Energy and industry research efforts to ensure the properties of materials in light water reactors are well understood. The ATR NSUF is providing this support through three main efforts: establishing unique infrastructure necessary to conduct research on highly radioactive materials, conducting research in conjunction with industry partners on life extension relevant topics, and providing training courses to encourage more U.S. researchers to understand and address LWR materials issues. In 2010 and 2011, several advanced instruments with capability focused on resolving nuclear material performance issues through analysis on the micro (10-6 m) to atomic (10-10 m) scales were installed primarily at the Center for Advanced Energy Studies (CAES) in Idaho Falls, Idaho. These instruments included a local electrode atom probe (LEAP), a field-emission gun scanning transmission electron microscope (FEG-STEM), a focused ion beam (FIB) system, a Raman spectrometer, and an nanoindentor/atomic force microscope. Ongoing capability enhancements intended to support industry efforts include completion of two shielded, irradiation assisted stress corrosion cracking (IASCC) test loops, the first of which will come online in early calendar year 2013, a …
Date: March 1, 2013
Creator: Jackson, John; Allen, Todd; Marshall, Frances & Cole, Jim
System: The UNT Digital Library
Advancements in Wind Integration Study Data Modeling: The Wind Integration National Dataset (WIND) Toolkit; Preprint (open access)

Advancements in Wind Integration Study Data Modeling: The Wind Integration National Dataset (WIND) Toolkit; Preprint

Regional wind integration studies in the United States require detailed wind power output data at many locations to perform simulations of how the power system will operate under high-penetration scenarios. The wind data sets that serve as inputs into the study must realistically reflect the ramping characteristics, spatial and temporal correlations, and capacity factors of the simulated wind plants, as well as be time synchronized with available load profiles. The Wind Integration National Dataset (WIND) Toolkit described in this paper fulfills these requirements. A wind resource dataset, wind power production time series, and simulated forecasts from a numerical weather prediction model run on a nationwide 2-km grid at 5-min resolution will be made publicly available for more than 110,000 onshore and offshore wind power production sites.
Date: October 1, 2013
Creator: Draxl, C.; Hodge, B. M.; Orwig, K.; Jones, W.; Searight, K.; Getman, D. et al.
System: The UNT Digital Library
AFM and NanoSIMS analyses of Vaccinia virions (open access)

AFM and NanoSIMS analyses of Vaccinia virions

None
Date: March 1, 2013
Creator: Weber, P K; Gates, S D; Malkin, A J; Condit, R C & Moussatche, N
System: The UNT Digital Library
ALGORITHMS FOR THERMAL AND MECHANICAL CONTACT IN N (open access)

ALGORITHMS FOR THERMAL AND MECHANICAL CONTACT IN N

The transfer of heat and force from UO2 pellets to
Date: May 1, 2013
Creator: Hales, J. D.; Andrs, D. & Gaston, D. R.
System: The UNT Digital Library
Analysis of Cadmium in Undissolved Anode Materials of Mark-IV Electrorefiner (open access)

Analysis of Cadmium in Undissolved Anode Materials of Mark-IV Electrorefiner

The Mark-IV electrorefiner (Mk-IV ER) contains an electrolyte/molten cadmium system for refining uranium electrochemically. Typically, the anode of the Mk-IV ER consists of the chopped sodium-bonded metallic driver fuels, which have been primarily U-10Zr binary fuels. Chemical analysis of the residual anode materials after electrorefining indicates that a small amount of cadmium is removed from the Mk-IV ER along with the undissolved anode materials. Investigation of chemical analysis data indicates that the amount of cadmium in the undissolved anode materials is strongly correlated with the anode rotation speeds and the residence time of the anode in the Mk-IV ER. Discussions are given to explain the prescribed correlation.
Date: October 1, 2013
Creator: Yoo, Tae-Sic; Fredrickson, Guy L.; Vaden, DeeEarl & Westphal, Brian R.
System: The UNT Digital Library
Analysis of fission gas release in LWR fuel using the BISON code (open access)

Analysis of fission gas release in LWR fuel using the BISON code

Recent advances in the development of the finite-element based, multidimensional fuel performance code BISON of Idaho National Laboratory are presented. Specifically, the development, implementation and testing of a new model for the analysis of fission gas behavior in LWR-UO2 fuel during irradiation are summarized. While retaining a physics-based description of the relevant mechanisms, the model is characterized by a level of complexity suitable for application to engineering-scale nuclear fuel analysis and consistent with the uncertainties pertaining to some parameters. The treatment includes the fundamental features of fission gas behavior, among which are gas diffusion and precipitation in fuel grains, growth and coalescence of gas bubbles at grain faces, grain growth and grain boundary sweeping effects, thermal, athermal, and transient gas release. The BISON code incorporating the new model is applied to the simulation of irradiation experiments from the OECD/NEA International Fuel Performance Experiments database, also included in the IAEA coordinated research projects FUMEX-II and FUMEX-III. The comparison of the results with the available experimental data at moderate burn-up is presented, pointing out an encouraging predictive accuracy, without any fitting applied to the model parameters.
Date: September 1, 2013
Creator: Pastore, G.; Hales, J. D.; Novascone, S. R.; Perez, D. M.; Spencer, B. W. & Williamson, R. L.
System: The UNT Digital Library
ANALYSIS OF OPERATIONAL STRATEGIES FOR UTILIZING CO2 FOR GEOTHERMAL ENERGY PRODUCTION (open access)

ANALYSIS OF OPERATIONAL STRATEGIES FOR UTILIZING CO2 FOR GEOTHERMAL ENERGY PRODUCTION

None
Date: February 1, 2013
Creator: Buscheck, T A; Chen, M; Lu, C; Sun, Y; Hao, Y; Celia, M A et al.
System: The UNT Digital Library
Analysis of the Impacts of Distribution-Connected PV Using High-Speed Data Sets: Preprint (open access)

Analysis of the Impacts of Distribution-Connected PV Using High-Speed Data Sets: Preprint

This paper, presented at the IEEE Green Technologies Conference 2013, utilizes information from high resolution data acquisition systems developed at the National Renewable Energy Laboratory and deployed on a high-penetration PV distribution system to analyze the variability of different electrical parameters. High-resolution solar irradiance data is also available in the same area which is used to characterize the available resource and how it affects the electrical characteristics of the study circuit. This paper takes a data-driven look at the variability caused by load and compares those results against times when significant PV production is present. Comparisons between the variability in system load and the variability of distributed PV generation are made.
Date: March 1, 2013
Creator: Bank, J. & Mather, B.
System: The UNT Digital Library
Analysis of Variability and Uncertainty in Wind Power Forecasting: An International Comparison: Preprint (open access)

Analysis of Variability and Uncertainty in Wind Power Forecasting: An International Comparison: Preprint

One of the critical challenges of wind power integration is the variable and uncertain nature of the resource. This paper investigates the variability and uncertainty in wind forecasting for multiple power systems in six countries. An extensive comparison of wind forecasting is performed among the six power systems by analyzing the following scenarios: (i) wind forecast errors throughout a year; (ii) forecast errors at a specific time of day throughout a year; (iii) forecast errors at peak and off-peak hours of a day; (iv) forecast errors in different seasons; (v) extreme forecasts with large overforecast or underforecast errors; and (vi) forecast errors when wind power generation is at different percentages of the total wind capacity. The kernel density estimation method is adopted to characterize the distribution of forecast errors. The results show that the level of uncertainty and the forecast error distribution vary among different power systems and scenarios. In addition, for most power systems, (i) there is a tendency to underforecast in winter; and (ii) the forecasts in winter generally have more uncertainty than the forecasts in summer.
Date: October 1, 2013
Creator: Zhang, J.; Hodge, B. M.; Gomez-Lazaro, E.; Lovholm, A. L.; Berge, E.; Miettinen, J. et al.
System: The UNT Digital Library
Analyzing Dynamic Probabilistic Risk Assessment Data through Topology-Based Clustering (open access)

Analyzing Dynamic Probabilistic Risk Assessment Data through Topology-Based Clustering

We investigate the use of a topology-based clustering technique on the data generated by dynamic event tree methodologies. The clustering technique we utilizes focuses on a domain-partitioning algorithm based on topological structures known as the Morse-Smale complex, which partitions the data points into clusters based on their uniform gradient flow behavior. We perform both end state analysis and transient analysis to classify the set of nuclear scenarios. We demonstrate our methodology on a dataset generated for a sodium-cooled fast reactor during an aircraft crash scenario. The simulation tracks the temperature of the reactor as well as the time for a recovery team to fix the passive cooling system. Combined with clustering results obtained previously through mean shift methodology, we present the user with complementary views of the data that help illuminate key features that may be otherwise hidden using a single methodology. By clustering the data, the number of relevant test cases to be selected for further analysis can be drastically reduced by selecting a representative from each cluster. Identifying the similarities of simulations within a cluster can also aid in the drawing of important conclusions with respect to safety analysis.
Date: September 1, 2013
Creator: Mandelli, Diego; Maljovec, Dan; BeiWang; Pascucci, Valerio & Bremer, Peer-Timo
System: The UNT Digital Library