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Methodology for characterizing modeling and discretization uncertainties in computational simulation

Description: This research effort focuses on methodology for quantifying the effects of model uncertainty and discretization error on computational modeling and simulation. The work is directed towards developing methodologies which treat model form assumptions within an overall framework for uncertainty quantification, for the purpose of developing estimates of total prediction uncertainty. The present effort consists of work in three areas: framework development for sources of uncertainty and error in the modeling and simulation process which impact model structure; model uncertainty assessment and propagation through Bayesian inference methods; and discretization error estimation within the context of non-deterministic analysis.
Date: March 1, 2000
Creator: ALVIN,KENNETH F.; OBERKAMPF,WILLIAM L.; RUTHERFORD,BRIAN M. & DIEGERT,KATHLEEN V.
Partner: UNT Libraries Government Documents Department
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Operational Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer

Description: This document comprises the Operational Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer. The objective of the testing was to verify that all equipment and components functioned as designed following construction completion and turnover to operations.
Date: March 28, 2000
Creator: ANDREWS, J.E.
Partner: UNT Libraries Government Documents Department
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The Adiabatic Matching Section Solution for the Source Injector

Description: Typical designs for a Heavy Ion Fusion Power Plant require the source injector to deliver 100 beams, packed into an array with a spacing of 7 cm. When designing source injectors using a single large aperture source for each beam, the emitter surfaces are packed into an array with a spacing of 30 cm. Thus, the matching section of the source injector must not only prepare the beam for transport in a FODO lattice, but also funnel the beams together. This can be accomplished by an ESQ matching section in which each beam travels on average at a slight angle to the axis of the quadrupoles and uses the focusing effect of the FODO lattice to maintain the angle. At the end of the matching section, doublet steering is used to bring the beams parallel to each other for injection into the main accelerator. A specific solution of this type for an 84-beam source injector is presented.
Date: March 1, 2000
Creator: Ahle, L.; Grote, D. P.; Halaza, E.; Henestroza, E.; Kwan, J. W. & MacLaren, S. A.
Partner: UNT Libraries Government Documents Department
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Results of the Recirculator Project at LLNL

Description: The Heavy Ion Fusion Group at Lawrence Livermore National Laboratory has for several years been developing the world's first circular induction accelerator designed for space charge dominated ion beams. Experiments on one quarter of the ring have been completed. The accelerator extended ten half-lattice periods (HLP) with induction cores for acceleration placed on every other HLP. A network of Capacitive Beam Probes (C-probes) was also enabled for beam position monitoring throughout the bend section. These C-probes have been instrumental in steering experiment, implementation of the acceleration stages and the dipole pulser, and the first attempts at coordinated bending and acceleration. Data from these experiments and emittance measurements will be presented.
Date: March 1, 2000
Creator: Ahle, L.; Sangster, T. C.; Barnard, J.; Burkhart, C.; Craig, G.; Debeling, A. et al.
Partner: UNT Libraries Government Documents Department
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Calibrated Properties Model

Description: The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the ''AMR Development Plan for U0035 Calibrated Properties Model REV00. These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions.
Date: March 12, 2000
Creator: Ahlers, C. & Liu, H.
Partner: UNT Libraries Government Documents Department
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Top quark physics

Description: The top quark, when it was finally discovered at Fermilab in 1995 completed the three-generation structure of the Standard Model (SM) and opened up the new field of top quark physics. Viewed as just another SM quark, the top quark appears to be a rather uninteresting species. Produced predominantly, in hadron-hadron collisions, through strong interactions, it decays rapidly without forming hadrons, and almost exclusively through the single mode t {r_arrow} Wb. The relevant CKM coupling V{sub tb} is already determined by the (three-generation) unitarity of the CKM matrix. Rare decays and CP violation are unmeasurable small in the SM. Yet the top quark is distinguished by its large mass, about 35 times larger than the mass of the next heavy quark, and intriguingly close to the scale of electroweak (EW) symmetry breaking. This unique property raises a number of interesting questions. Is the top quark mass generated by the Higgs mechanism as the SM predicts and is its mass related to the top-Higgs-Yukawa coupling? Or does it play an even more fundamental role in the EW symmetry breaking mechanism? If there are new particles lighter than the top quark, does the top quark decay into them? Could non-SM physics first manifest itself in non-standard couplings of the top quark which show up as anomalies in top quark production and decays? Top quark physics tries to answer these questions. Several properties of the top quark have already been examined at the Tevatron. These include studies of the kinematical properties of top production, the measurements of the top mass, of the top production cross-section, the reconstruction of t{bar t}pairs in the fully hadronic final states, the study of {tau} decays of the top quark, the reconstruction of hadronic decays of the W boson from top decays, the search for flavor changing neutral …
Date: March 24, 2000
Creator: Ahmadov, A.; Azuelos, G.; Bauer, U.; Belyaev, A.; Berger, E. L.; Sullivan, Z. et al.
Partner: UNT Libraries Government Documents Department
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CuPt-B ordered microstructures in GaInP and GaInAs films

Description: The authors examine CuPt-B atomic sublattice ordering in Ga{sub 0.51}In{sub 0.49}P (GaInP) and Ga{sub 0.47}In{sub 0.53}As (GaInAs) III-V alloy films grown by atmospheric- and low-pressure metalorganic chemical vapor deposition on singular and vicinal (001) substrates. The influences of growth conditions and substrate miscut on double- and single-variant ordered microstructures are investigated using transmission electron microscopy (TEM). Relatively thick (>1-2 {micro}m) double-variant ordered GaInP and GaInAs films show complementary superdomain formation. Single-variant ordered films on <111>B-miscut substrates contain single-phase domains, separated by antiphase boundaries (APBs). The appearance of APBs in TEM dark-field images is anticipated from electron diffraction theory.
Date: March 1, 2000
Creator: Ahrenkiel, S. P.; Jones, K. M.; Matson, R. J.; Al-Jassim, M. M.; Zhang, Y.; Mascarenhas, A. et al.
Partner: UNT Libraries Government Documents Department
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{sup 17}O NMR Investigation of Oxidative Degradation in Polymers Under Gamma-Irradiation

Description: The {gamma}-irradiated-oxidation of pentacontane (C{sub 50}H{sub 102}) and the polymer polyisoprene was investigated as a function of oxidation level using {sup 17}O nuclear magnetic resonance (NMR) spectroscopy. It is demonstrated that by using {sup 17}O labeled O{sub 2} gas during the {gamma}-irradiation process, details about the oxidative degradation mechanisms can be directly obtained from the analysis of the {sup 17}O NMR spectra. Production of carboxylic acids is the primary oxygen-containing functionality during the oxidation of pentacontane, while ethers and alcohols are the dominant oxidation product observed for polyisoprene. The formation of ester species during the oxidation process is very minor for both materials, with water also being produced in significant amounts during the radiolytic oxidation of polyisoprene. The ability to focus on the oxidative component of the degradation process using {sup 17}O NMR spectroscopy demonstrates the selectivity of this technique over more conventional approaches.
Date: March 8, 2000
Creator: Alam, Todd M.; Celina, Mathias C.; Assink, Roger A.; Clough, Roger Lee & Gillen, Kenneth T.
Partner: UNT Libraries Government Documents Department
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Beyond the dna: a prototype for functional genomics

Description: A prototype oligonucleotide ''functional chip'' has been developed to screen novel DNA repair proteins for their ability to bind or alter different forms of DNA. This chip has been developed as a functional genomics screen for analysis of protein-DNA interactions for novel proteins identified from the Human Genome Project The process of novel gene identification that has ensued as a consequence of available sequence information is remarkable. The challenge how lies in determining the function of newly identified gene products in a time-and cost-effective high-throughput manner. The functional chip is generated by the robotic application of DNA spotted in a microarray format onto a glass slide. Individual proteins are then analyzed against the different form of DNA bound to the slide. Several prototype functional chips were designed to contain various DNA fragments tethered to a glass slide for analysis of protein-DNA binding or enzymatic activity of known proteins. The technology has been developed to screen novel, putative DNA repair proteins for their ability to bind various types of DNA alone and in concert with protein partners. An additional scheme has been devised to screen putative repair enzymes for their ability to process different types of DNA molecules. Current methods to analyze gene expression primarily utilize either of two technologies. The oligonucleotide chip, pioneered by Fodor and co-workers and Affymetrix, Inc., consists of greater than 64,000 oligonucleotides attached in situ to a glass support. The oligonucleotide chip has been used primarily to identify specific mutations in a given gene by hybridization against a fluorescently-labeled substrate. The second method is the microarray, whereby DNA targets are systematically arranged on a glass slide and then hybridized with fluorescently-labeled complex targets for gene expression analysis (Jordan, 1998). By this technique, a large amount of information can be obtained examining global differences in gene expression …
Date: March 2, 2000
Creator: Albala, J
Partner: UNT Libraries Government Documents Department
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Binary Microlensing Events from the MACHO Project

Description: This article presents the light curves of 21 gravitational microlensing events from the first six years of the MACHO Project gravitational microlensing survey that are likely examples of lensing by binary systems.
Date: March 27, 2000
Creator: Alcock, C.; Allsman, R. A.; Alves, D.; Axelrod, T. S.; Baines, D.; Becker, A. C. et al.
Partner: UNT College of Arts and Sciences
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Tanks Focus Area Site Needs Assessment FY 2000

Description: This document summarizes the Tanks Focus Area (TFA's) process of collecting, analyzing, and responding to high-level radioactive tank waste science and technology needs developed from across the DOE complex in FY 2000. The document also summarizes each science and technology need, and provides an initial prioritization of TFA's projected work scope for FY 2001 and FY 2002.
Date: March 10, 2000
Creator: Allen, Robert W.
Partner: UNT Libraries Government Documents Department
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Hands-free operation of a small mobile robot

Description: The Intelligent Systems and Robotics Center of Sandia National laboratories has an ongoing research program in advanced user interfaces. As part of this research, promising new transduction devices, particularly hands-free devices, are being explored for the control of mobile and floor-mounted robotic systems. Brainwave control has been successfully demonstrated by other researchers in a variety of fields. In the research described here, Sandia developed and demonstrated a proof-of-concept brainwave-controlled mobile robot system. Preliminary results were encouraging. Additional work required to turn this into a reliable. fieldable system for mobile robotic control is identified. Used in conjunction with other controls, brainwave control could be an effective control method in certain circumstances.
Date: March 14, 2000
Creator: Amai, Wendy A.; Fahrenholtz,Jill C. & Leger, Chris L.
Partner: UNT Libraries Government Documents Department
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Dedicated OO expertise applied to Run II software projects

Description: The change in software language and methodology by CDF and D0 to object-oriented from procedural Fortran is significant. Both experiments requested dedicated expertise that could be applied to software design, coding, advice and review. The Fermilab Run II offline computing outside review panel agreed strongly with the request and recommended that the Fermilab Computing Division hire dedicated OO expertise for the CDF/D0/Computing Division joint project effort. This was done and the two experts have been an invaluable addition to the CDF and D0 upgrade software projects and to the Computing Division in general. These experts have encouraged common approaches and increased the overall quality of the upgrade software. Advice on OO techniques and specific advice on C++ coding has been used. Recently a set of software reviews has been accomplished. This has been a very successful instance of a targeted application of computing expertise, and constitutes a very interesting study of how to move toward modern computing methodologies in HEP.
Date: March 7, 2000
Creator: Amidei, D.
Partner: UNT Libraries Government Documents Department
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Arc-Discharge Ion Sources for Heavy Ion Fusion

Description: A miniature multiple beamlet approach to an injector system was recently proposed in order to reduce the size, cost, and power requirements of the injector. The beamlets of very high current density are needed to meet the brightness requirement. Besides vacuum arc ion sources, cold-cathode gas ion sources are candidates for this application. Vacuum-arc metal ion sources and vacuum-arc-like gas ion sources are discussed. Experiments are presented that focus on the short-pulse plasma composition and ion charge state distribution. Mg and Sr have been identified as the most promising metals leading to mono-species beams when 20 {mu}s arc pulses are used. It is shown that the efficient production of gas ions requires the presence of a magnetic field.
Date: March 1, 2000
Creator: Anders, A. & Kwan, J. W.
Partner: UNT Libraries Government Documents Department
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Hydrogen generation in tru waste transportation packages

Description: This document addresses hydrogen generation in TRU waste transportation packages. The potential sources of hydrogen generation are summarized with a special emphasis on radiolysis. After defining various TRU wastes according to groupings of material types, bounding radiolytic G-values are established for each waste type. Analytical methodologies are developed for prediction of hydrogen gas concentrations for various packaging configurations in which hydrogen generation is due to radiolysis. Representative examples are presented to illustrate how analytical procedures can be used to estimate the hydrogen concentration as a function of time. Methodologies and examples are also provided to show how the time to reach a flammable hydrogen concentration in the innermost confinement layer can be estimated. Finally, general guidelines for limiting the hydrogen generation in the payload and hydrogen accumulation in the innermost confinement layer are described.
Date: March 27, 2000
Creator: Anderson, B; Sheaffer, M K & Fischer, L E
Partner: UNT Libraries Government Documents Department
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Customer satisfaction assessment at the Pacific Northwest National Laboratory

Description: The Pacific Northwest National Laboratory (PNNL) is developing and implementing a customer satisfaction assessment program (CSAP) to assess the quality of research and development provided by the laboratory. This report presents the customer survey component of the PNNL CSAP. The customer survey questionnaire is composed of two major sections: Strategic Value and Project Performance. Both sections contain a set of questions that can be answered with a 5-point Likert scale response. The strategic value section consists of five questions that are designed to determine if a project directly contributes to critical future national needs. The project Performance section consists of nine questions designed to determine PNNL performance in meeting customer expectations. A statistical model for customer survey data is developed and this report discusses how to analyze the data with this model. The properties of the statistical model can be used to establish a gold standard or performance expectation for the laboratory, and then to assess progress. The gold standard is defined using laboratory management input--answers to four questions, in terms of the information obtained from the customer survey: (1) What should the average Strategic Value be for the laboratory project portfolio? (2) What Strategic Value interval should include most of the projects in the laboratory portfolio? (3) What should average Project Performance be for projects with a Strategic Value of about 2? (4) What should average Project Performance be for projects with a Strategic Value of about 4? To be able to provide meaningful answers to these questions, the PNNL customer survey will need to be fully implemented for several years, thus providing a link between management perceptions of laboratory performance and customer survey data.
Date: March 23, 2000
Creator: Anderson, DN & Sours, ML
Partner: UNT Libraries Government Documents Department
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Customer Satisfaction Assessment at the Pacific Northwest National Laboratory

Description: The Pacific Northwest National Laboratory (PNNL) is developing and implementing a customer satisfaction assessment program (CSAP) to assess the quality of research and development provided by the laboratory. We present the customer survey component of the PNNL CSAP. The customer survey questionnaire is composed of 2 major sections, Strategic Value and Project Performance. The Strategic Value section of the questionnaire consists of 5 questions that can be answered with a 5 point Likert scale response. These questions are designed to determine if a project is directly contributing to critical future national needs. The Project Performance section of the questionnaire consists of 9 questions that can be answered with a 5 point Likert scale response. These questions determine PNNL performance in meeting customer expectations. Many approaches could be used to analyze customer survey data. We present a statistical model that can accurately capture the random behavior of customer survey data. The properties of this statistical model can be used to establish a "gold standard'' or performance expectation for the laboratory, and then assess progress. The gold standard is defined from input from laboratory management --- answers to 4 simple questions, in terms of the information obtained from the CSAP customer survey, define the standard: *What should the average Strategic Value be for the laboratory project portfolio? *What Strategic Value interval should include most of the projects in the laboratory portfolio? *What should average Project Performance be for projects with a Strategic Value of about 2? *What should average Project Performance be for projects with a Strategic Value of about 4? We discuss how to analyze CSAP customer survey data with this model. Our discussion will include "lessons learned" and issues that can invalidate this type of assessment.
Date: March 20, 2000
Creator: Anderson, Dale N. & Sours, Mardell L.
Partner: UNT Libraries Government Documents Department
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LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and Testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Progress has been made in the preparation and characterization of thin electrolytes and porous LSM substrates. Both of these tasks are essentially on or ahead of schedule. In our proposal, we suggested that the ZrO{sub 2}/Sc system needed to be considered as a candidate as a thin electrolyte. This was because microcrystalline ZrO{sub 2}/Sc has a significantly higher ionic conductivity than YSZ, particularly at the lower temperatures. As a result, some 0.5 micron thick film of ZrO{sub 2}/16% Sc on an alumina substrate (grain size 20nm) was prepared and the electrical conductivity measured as a function of temperature and oxygen activity. The Sc doped ZrO{sub 2} certainly has a higher conductivity that either 20nm or 2400nm YSZ, however, electronic conductivity dominates the conductivity for oxygen activities below 10{sup -15}. Whereas for YSZ, electronic conductivity is not a problem until the oxygen activity decreases below 10{sup -25}. These initial results show that the ionic conductivity of 20nm YSZ and 20nm ZrO{sub 2}/16% Sc are essentially the same and the enhanced conductivity which is observed for Sc doping in microcrystalline specimens is not observed for the same composition when it is nanocrystalline. In addition they show that the electronic conductivity of Sc doped ZrO{sub 2} is at least two orders of magnitude higher than that observed for YSZ. The conclusion one reaches is that for 0.5 to 1 micron thick nanocrystalline films, Sc doping of ZrO{sub 2} has no benefits compared to YSZ. As a result, electrolyte films of …
Date: March 31, 2000
Creator: Anderson, Harlan U.
Partner: UNT Libraries Government Documents Department
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Recovery of Valuable Chlorosilane Intermediates by a Novel Waste Conversion Process, Phase IIIB (Progress)

Description: From June 1998 through September 1999, direct process residue (DPR, a waste byproduct) hydrogenolysis has been studied at a large pilot plant within Dow Corning's Carrollton, KY, facility. The system reacts filtered DPR with chlorosilane monomers at high temperature and pressure. The process routinely demonstrates DPR conversions from 59% to 89% on a monthly basis. The reaction product contains high concentrations of valuable monomers such as dimethyldichlorosilane and methyldichlorosilane. An expansion of the current unit's capacity is planned to be on-line by the end of CY2000. Furthermore, a larger DPR hydrogenolysis reactor based on these results is being designed for operation in Europe at Dow Corning's Barry, Wales, site.
Date: March 31, 2000
Creator: Anderson, Kurt E.
Partner: UNT Libraries Government Documents Department
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Invert Effective Thermal Conductivity Calculation

Description: The objective of this calculation is to evaluate the temperature-dependent effective thermal conductivities of a repository-emplaced invert steel set and surrounding ballast material. The scope of this calculation analyzes a ballast-material thermal conductivity range of 0.10 to 0.70 W/m {center_dot} K, a transverse beam spacing range of 0.75 to 1.50 meters, and beam compositions of A 516 carbon steel and plain carbon steel. Results from this calculation are intended to support calculations that identify waste package and repository thermal characteristics for Site Recommendation (SR). This calculation was developed by Waste Package Department (WPD) under Office of Civilian Radioactive Waste Management (OCRWM) procedure AP-3.12Q, Revision 1, ICN 0, Calculations.
Date: March 17, 2000
Creator: Anderson, M. J.; Wade, H. M. & Mitchell, T. L.
Partner: UNT Libraries Government Documents Department
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