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A texture-based frameowrk for improving CFD data visualization in a virtual environment

Description: In the field of computational fluid dynamics (CFD) accurate representations of fluid phenomena can be simulated but require large amounts of data to represent the flow domain. Most datasets generated from a CFD simulation can be coarse, {approx} 10,000 nodes or cells, or very fine with node counts on the order of 1,000,000. A typical dataset solution can also contain multiple solutions for each node, pertaining to various properties of the flow at a particular node. Scalar properties such as density, temperature, pressure, and velocity magnitude are properties that are typically calculated and stored in a dataset solution. Solutions are not limited to just scalar properties. Vector quantities, such as velocity, are also often calculated and stored for a CFD simulation. Accessing all of this data efficiently during runtime is a key problem for visualization in an interactive application. Understanding simulation solutions requires a post-processing tool to convert the data into something more meaningful. Ideally, the application would present an interactive visual representation of the numerical data for any dataset that was simulated while maintaining the accuracy of the calculated solution. Most CFD applications currently sacrifice interactivity for accuracy, yielding highly detailed flow descriptions but limiting interaction for investigating the field.
Date: May 1, 2005
Creator: Biveins, Gerrick O'Ron
Partner: UNT Libraries Government Documents Department

A texture-based framework for improving CFD data visualization in a virtual environment

Description: In the field of computational fluid dynamics (CFD) accurate representations of fluid phenomena can be simulated hut require large amounts of data to represent the flow domain. Most datasets generated from a CFD simulation can be coarse, {approx}10,000 nodes or cells, or very fine with node counts on the order of 1,000,000. A typical dataset solution can also contain multiple solutions for each node, pertaining to various properties of the flow at a particular node. Scalar properties such as density, temperature, pressure, and velocity magnitude are properties that are typically calculated and stored in a dataset solution. Solutions are not limited to just scalar properties. Vector quantities, such as velocity, are also often calculated and stored for a CFD simulation. Accessing all of this data efficiently during runtime is a key problem for visualization in an interactive application. Understanding simulation solutions requires a post-processing tool to convert the data into something more meaningful. Ideally, the application would present an interactive visual representation of the numerical data for any dataset that was simulated while maintaining the accuracy of the calculated solution. Most CFD applications currently sacrifice interactivity for accuracy, yielding highly detailed flow descriptions hut limiting interaction for investigating the field.
Date: May 5, 2005
Creator: Bivins, Gerrick O'Ron
Partner: UNT Libraries Government Documents Department

STANDARD ATOMIC WEIGHTS TABLES 2007 ABRIDGED TO FOUR AND FIVE SIGNIFICANT FIGURES.

Description: In response to a recommendation to the Commission on Isotopic Abundances and Atomic Weights (CIAAW) that abridged versions of the Table on Standard Atomic Weights be prepared and published, this report has been prepared. A brief history is presented of such Atomic Weight tables that have been abridged to four significant figures and to five significant figures are noted. Tables of Standard Atomic Weight values abridged to four places and five places from the official 2007 Table of Atomic Weights approved by CIAAW are included.
Date: August 1, 2007
Creator: HOLDEN,N.E.
Partner: UNT Libraries Government Documents Department

Random polycrystals of grains containing cracks: Model ofquasistatic elastic behavior for fractured systems

Description: A model study on fractured systems was performed using aconcept that treats isotropic cracked systems as ensembles of crackedgrains by analogy to isotropic polycrystalline elastic media. Theapproach has two advantages: (a) Averaging performed is ensembleaveraging, thus avoiding the criticism legitimately leveled at mosteffective medium theories of quasistatic elastic behavior for crackedmedia based on volume concentrations of inclusions. Since crack effectsare largely independent of the volume they occupy in the composite, sucha non-volume-based method offers an appealingly simple modelingalternative. (b) The second advantage is that both polycrystals andfractured media are stiffer than might otherwise be expected, due tonatural bridging effects of the strong components. These same effectshave also often been interpreted as crack-crack screening inhigh-crack-density fractured media, but there is no inherent conflictbetween these two interpretations of this phenomenon. Results of thestudy are somewhat mixed. The spread in elastic constants observed in aset of numerical experiments is found to be very comparable to the spreadin values contained between the Reuss and Voigt bounds for thepolycrystal model. However, computed Hashin-Shtrikman bounds are much tootight to be in agreement with the numerical data, showing thatpolycrystals of cracked grains tend to violate some implicit assumptionsof the Hashin-Shtrikman bounding approach. However, the self-consistentestimates obtained for the random polycrystal model are nevertheless verygood estimators of the observed average behavior.
Date: July 8, 2006
Creator: Berryman, James G. & Grechka, Vladimir
Partner: UNT Libraries Government Documents Department

Statistical characterization of dislocation ensembles

Description: We outline a method to study the spatial and orientation statistics of dynamical dislocation systems by modeling the dislocations as a stochastic fiber process. Statistical measures have been introduced for the density, velocity, and flux of dislocations, and the connection between these measures and the dislocation state and plastic distortion rate in the crystal is explained. A dislocation dynamics simulation model has been used to extract numerical data to study the evolution of these statistical measures numerically in a body-centered cubic crystal under deformation. The orientation distribution of the dislocation density, velocity and dislocation flux, as well as the dislocation correlations have been computed. The importance of the statistical measures introduced here in building continuum models of dislocation systems is highlighted.
Date: May 17, 2006
Creator: El-Azab, A; Deng, J & Tang, M
Partner: UNT Libraries Government Documents Department

Evaluated decay data for {sup 246}Cm.

Description: The Nuclear Data and Measurement Series document results of studies in the field of microscopic nuclear data. The primary objective is the dissemination of information in the comprehensive form required for nuclear technology applications. This Series is devoted to: (a) measured microscopic nuclear parameters, (b) experimental techniques and facilities employed in measurements, (c) the analysis, correlation and interpretation of nuclear data, and (d) the compilation and evaluation of nuclear data. Contributions to this Series are reviewed to assure technical competence and, unless otherwise stated, the contents can be formally referenced. This Series does not supplant formal journal publication, but it does provide the more extensive information required for technological applications (e.g., tabulated numerical data) in a timely manner.
Date: February 26, 2007
Creator: Kondev, F. G.
Partner: UNT Libraries Government Documents Department

Final long-term surveillance plan for the Spook, Wyoming, disposal site

Description: A general license for the custody and long-term care of DOE Uranium Mill Tailings Remedial Action (UMTRA) Project permanent disposal sites was issued by the US Nuclear Regulatory Commission (NRC), and became effective on November 29, 1990. The general license will be in effect for a specific disposal site when the NRC accepts the disposal site`s long-term surveillance plan (LTSP) and concurs that remedial action is complete at that site. This document describes in detail the long-term surveillance activities for the Spook, Wyoming, disposal site, including monitoring, maintenance, and emergency measures necessary to fulfill the conditions of the general license, and to ensure that the disposal cell continues to comply with the UMTRA design standards.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department

Hanford Site climatological data summary 1995 with historical data

Description: This document presents the climatological data measured at the US Department of Energy`s Hanford Site for calendar year 1995. Pacific Northwest National Laboratory operates the Hanford Meteorology Station and the Hanford Meteorological Monitoring Network from which these data were collected. The information contained herein includes updated historical climatologies for temperature, precipitation, normal and extreme values of temperature and precipitation, and other miscellaneous meteorological parameters. Further, the data are adjunct to and update Hoitink and Burk (1994, 1995); however, Appendix B--Wind Climatology (1994) is excluded. 1995 was warmer than normal, averaging 54.7 F, 1.4 F above normal (53.3 F). For the 12-month period, 8 months were warmer than normal, and 4 were cooler than normal. 1995 was the wettest year on record. Precipitation totaled 12.31 in., 197% of normal (6.26 in.); snowfall totaled 7.7 in., compared to the normal of 13.8 in. The average wind speed during 1995 was 7.8 mph, 0.1 mph above normal (7.7 mph). The peak gust during the year was 61 mph from the south-southwest on December 12. There were 27 days with peak gusts {ge} 40 mph, compared to a yearly average of 26.
Date: May 1, 1996
Creator: Hoitink, D.J. & Burk, K.W.
Partner: UNT Libraries Government Documents Department

Surface water and atmospheric underway carbon data obtained during the World Ocean Circulation Experiment Indian Ocean survey cruises (R/V Knorr, December 1998--January 1996)

Description: This data documentation presents the results of the surface water and atmospheric underway measurements of mole fraction of carbon dioxide (xCO{sub 2}), sea surface salinity, and sea surface temperature, obtained during the World Ocean Circulation Experiment (WOCE) Indian Ocean survey cruises (December 1994--January 1996). Discrete and underway carbon measurements were made by members of the CO{sub 2} survey team. The survey team is a part of the Joint Global Ocean Flux Study supported by the US Department of Energy to make carbon-related measurements on the WOCE global survey cruises. Approximately 200,000 surface seawater and 50,000 marine air xCO{sub 2} measurements were recorded.
Date: November 1, 1997
Creator: Kozyr, A. & Allison, L.
Partner: UNT Libraries Government Documents Department

Large-scale demonstration and deployment project at Los Alamos National Laboratory

Description: Established by the US Department of Energy (DOE) Environmental Management program through its Office of Science and Technology, the Deactivation and Decommissioning Focus Area is developing answers to the technological problems that hinder Environmental Management`s extensive cleanup efforts. The optimized application of technologies to ongoing nuclear facility decontamination and dismantlement is critical in meeting the challenge of decommissioning approximately 9,000 buildings and structures within the DOE complex. The significant technical and economic concerns in this area underscore a national imperative for the qualification and timely delivery of cost-reduction technologies and management approaches to meet federal and private needs. At Los Alamos National Laboratory (LANL), a Large-Scale Demonstration and Deployment Project (LSDDP) has been established to facilitate demonstration and deployment of technologies for the characterization, decontamination, and volume reduction of oversized metallic waste, mostly in the form of gloveboxes contaminated with transuranic radionuclides. The LANL LSDDP is being managed by an integrated contractor team (ICT) consisting of IT Corporation, ICF Incorporated, and Florida International University and includes representation from LANL`s Environmental Management Program Office. The ICT published in the Commerce Business Daily a solicitation for interest for innovative technologies capable of improving cost and performance of the baseline process. Each expression of interest response was evaluated and demonstration contract negotiations are under way for those technologies expected to be capable of meeting the project objectives. This paper discusses management organization and approach, the results of the technology search, the technology selection methodology, the results of the selection process, and future plans for the program.
Date: April 1, 1999
Creator: Brown, S.; McFee, J.; Broom, C.; Dugger, H. & Stallings, E.
Partner: UNT Libraries Government Documents Department

Semi-annual report of the Department of Energy, Office of Environmental Management, Quality Assessment Program

Description: This report presents the results from the analysis of the 44th set of environmental quality assessment samples (QAP XLIV) that were received on or before June 3, 1996. The QAP is designed to test the quality of environmental measurements being reported to the Department of Energy by it`s contractors. Since 1976, samples have been prepared and analyzed by the Environmental measurements Laboratory.
Date: July 1, 1996
Creator: Sanderson, C.G. & Greenlaw, P.
Partner: UNT Libraries Government Documents Department

Hanford Site National Environmental Policy Act (NEPA) characterization. Revision 10

Description: This document describes the US Department of Energy`s (DOE) Hanford Site environment and is numbered to correspond to the chapters where such information is presented in Hanford Site NEPA related documents. The document is intended to provide a consistent description of the Hanford Site environment for the many NEPA documents that are being prepared by contractors. The two chapters in this document (Chapters 4 and 6) are numbered this way to correspond to the chapters where such information is presented in environmental impact statements (EISs) and other Site-related NEPA or CERCLA documentation. Chapter 4.0 (Affected Environment) describes the Hanford Site environment, and includes information on climate and meteorology, geology, hydrology, ecology, cultural, archaeological and historical resources, socioeconomics, and noise. Chapter 6.0 (Statutory and Regulatory Requirements) describes applicable federal and state laws and regulations, DOE directives and permits, and environmental standards directly applicable to the NEPA documents on the Hanford Site.
Date: September 1, 1998
Creator: Neitzel, D.A.; Fosmire, C.J. & Fowler, R.A.
Partner: UNT Libraries Government Documents Department

BCLDP site environmental report for calendar year 1997 on radiological and nonradiological parameters

Description: Battelle Memorial Institute currently maintains its retired nuclear research facilities in a surveillance and maintenance (S and M) mode and continues decontamination and decommissioning (D and D) activities. The activities are referred to as the Battelle Columbus Laboratories Decommissioning Project (BCLDP). Operations reference in this report are performed in support of S and M and D and D activities. The majority of this report is devoted to discussion of the West Jefferson facility, because the source term at this facility is larger than the source term at Battelle`s King Avenue site. The contamination found at the King Avenue site consists of small amounts of residual radioactive material in solid form, which has become embedded or captured in nearby surfaces such as walls, floors, ceilings, drains, laboratory equipment, and soils. By the end of calendar year (CY) 1997, most remediation activities were completed at the King Avenue site. The contamination found at the West Jefferson site is the result of research and development activities with irradiated materials. During CY 1997, multiple tests at the West Jefferson Nuclear Sciences Area found no isotopes present above the minimum detectable activity (MDA) for air releases or for liquid discharges to Big Darby Creek. Data obtained from downstream sampling locations were statistically indistinguishable from background levels.
Date: September 30, 1998
Creator: Fry, J.
Partner: UNT Libraries Government Documents Department

The size of a polymer of string-bits: a numerical investigation

Description: In string bit models, string is described as a polymer of point-like constituents. We attempt to use string-bit ideas to investigate how the size of string is affected by string interactions in a non-perturbative context. Lacking adequate methods to deal with the full complications of bit rearrangement interactions, we study instead a simplified analog model with only ``direct`` potential interactions among the bits. We use the variational principle in an approximate calculation of the mean-square size of a polymer as a function of the number of constituents/bits for various interaction strengths {ital g} in three specific models. 14 refs., 2 figs.
Date: April 1, 1997
Creator: Bergman, O. & Thorn, C.B.
Partner: UNT Libraries Government Documents Department

Electric co-heating in the ASHRAE standard method of test for thermal distribution efficiency: Test results on two New York State homes

Description: Electric co-heating tests on two single-family homes with forced-air heating systems were carried out in March 1995. The goal of these tests was to evaluate procedures being considered for incorporation in a Standard Method of Test for thermal distribution system efficiency now being developed by ASHRAE. Thermal distribution systems are the ductwork, piping, or other means used to transport heat or cooling effect from the building equipment that produces this thermal energy to the spaces in which it is used. Furthering the project goal, the first objective of the tests was to evaluate electric co-heating as a means of measuring system efficiency. The second objective was to investigate procedures for obtaining the distribution efficiency, using system efficiency as a base. Distribution efficiencies of 0.63 and 0.70 were obtained for the two houses.
Date: October 1, 1995
Creator: Andrews, J.W.; Krajewski, R.F. & Strasser, J.J.
Partner: UNT Libraries Government Documents Department

Semi-annual report of the Department of Energy, Office of Environmental Management, Quality Assessment Program

Description: This Quality Assessment Program (QAP) is designed to test the quality of the environmental measurements being reported to the Department of Energy by its contractors. Since 1976, real or synthetic environmental samples that have been prepared and thoroughly analyzed at the Environmental Measurements Laboratory (EML) have been distributed at first quarterly and then semi-annually to these contractors. Their results, which are returned to EML within 90 days, are compiled with EML`s results and are reported back to the participating contractors 30 days later. This report presents the results from the analysis of the 48th set of environmental quality assessment samples (QAP XLVIII) that were received on or before June 1, 1998.
Date: July 1, 1998
Creator: Greenlaw, P.D. & Minick, S.K.
Partner: UNT Libraries Government Documents Department

Managing Senegalese water resources: Definition and relative importance of information needs

Description: This report provides an overview of the results of the Vital Issues process as implemented for the Senegal Water Resources Management Initiative, a collaborative effort between the Senegalese Ministry of Water Resources and Sandia National Laboratories. This Initiative is being developed to assist in the development of an efficient and sustainable water resources management system for Senegal. The Vital Issues process was used to provide information for the development of a proposal that will recommend actions to address the key management issues and establish a state-of-the-art decision support system (DSS) for managing Senegal`s water resources. Three Vital Issues panel meetings were convened to (1) develop a goal statement and criteria for identifying and ranking the issues vital to water resources management in Senegal; (2) define and rank the issues, and (3) identify and prioritize a preliminary list of information needed to address the vital issues. The selection of panelists from the four basic institutional perspectives (government, industry, academe, and citizens` interest groups) ensured a high level of stakeholder representation on the panels.
Date: September 1998
Creator: Engi, D.
Partner: UNT Libraries Government Documents Department

Equation of state for detonation products

Description: To be useful, an equation of state for detonation products must allow rapid computation. The constraints applied by this requirement have surprising thermodynamic effects. Some of these are discussed here. A simple, complete equation of state is proposed, and its properties are discussed. With the form assumed here, all the useful integrals (except for the Riemann integral) can be written simply and explicitly, so the behavior of the important variables can be easily seen. The complete equation of state is calibrated for PBX9404 and PBX9501.
Date: December 31, 1998
Creator: Davis, W.C.
Partner: UNT Libraries Government Documents Department

Polycyclic aromatic hydrocarbons at selected burning grounds at Los Alamos National Laboratory

Description: A commercial immunoassay field test (IFT) was used to rapidly assess the total concentrations of polycyclic aromatic hydrocarbons (PAHs) in the soil at selected burning grounds within the explosives corridor at Los Alamos National Laboratory (LANL). Results were compared with analyses obtained from LANL Analytical Laboratory and from a commercial laboratory. Both used the Environmental Protection Agency`s (EPA`s) Methods 8270 and 8310. EPA`s Method 8270 employs gas chromatography and mass spectral analyses, whereas EPA`s Method 8310 uses an ultraviolet detector in a high-performance liquid chromatography procedure. One crude oil sample and one diesel fuel sample, analyzed by EPA Method 8270, were included for references. On an average the IFT results were lower for standard samples and lower than the analytical laboratory results for the unknown samples. Sites were selected to determine whether the PAHs came from the material burned or the fuel used to ignite the burn, or whether they are produced by a high-temperature chemical reaction during the burn. Even though the crude oil and diesel fuel samples did contain measurable quantities of PAHs, there were no significant concentrations of PAHs detected in the ashes and soil at the burning grounds. Tests were made on fresh soil and ashes collected after a large burn and on aged soil and ashes known to have been at the site more than three years. Also analyzed were twelve-year-old samples from an inactive open burn cage.
Date: February 1, 1998
Creator: Harris, B.W.; Minor, L.K.M. & Flucas, B.J.
Partner: UNT Libraries Government Documents Department

Weldon Spring Site Remedial Action Project quarterly environmental data summary for second quarter 1998

Description: In support of the Weldon Spring Site Remedial Action Project Federal Facilities Agreement, a copy of the Quarterly Environmental Data Summary (QEDS) for the second quarter of 1998 is enclosed. The data presented constitutes the QEDS. The data were received from the contract laboratories, verified by the Weldon Spring Site verification group and, except for air monitoring data and site KPA generated data (uranium analyses), merged into the database during the second quarter of 1998. Air monitoring data presented are the most recent complete sets of quarterly data. Air data are not stored in the database and KPA data are not merged into the regular database. All data received and verified during the second quarter were within a permissible range of variability, except for those listed. Above normal occurrences are cited for groundwater, air, and NPDES data. There were no above normal occurrences for springs or surface water. The attached tables present the most recent data for air and the data merged into the database during the second quarter 1998 for groundwater, NPDES, surface water, and springs.
Date: August 11, 1998
Partner: UNT Libraries Government Documents Department

Pen Branch delta expansion

Description: Since 1954, cooling water discharges from K Reactor ({anti X} = 370 cfs {at} 59 C) to Pen Branch have altered vegetation and deposited sediment in the Savannah River Swamp forming the Pen Branch delta. Currently, the delta covers over 300 acres and continues to expand at a rate of about 16 acres/yr. Examination of delta expansion can provide important information on environmental impacts to wetlands exposed to elevated temperature and flow conditions. To assess the current status and predict future expansion of the Pen Branch delta, historic aerial photographs were analyzed using both basic photo interpretation and computer techniques to provide the following information: (1) past and current expansion rates; (2) location and changes of impacted areas; (3) total acreage presently affected. Delta acreage changes were then compared to historic reactor discharge temperature and flow data to see if expansion rate variations could be related to reactor operations.
Date: February 1, 1984
Creator: Nelson, E.A.; Christensen, E.J.; Mackey, H.E.; Sharitz, R.R.; Jensen, J.R. & Hodgson, M.E.
Partner: UNT Libraries Government Documents Department