Resource Type

Texas Racing Commission Annual Report: 2004 (open access)

Texas Racing Commission Annual Report: 2004

Annual report of the Texas Racing Commission describing goals, activities, and accomplishments during fiscal year 2004
Date: April 8, 2005
Creator: Texas Racing Commission
System: The Portal to Texas History
Formulation of the Linear Response Theory in Relativistic LAPW Method. Calculation of Forces in Alpha-Pu (open access)

Formulation of the Linear Response Theory in Relativistic LAPW Method. Calculation of Forces in Alpha-Pu

Linear-response (LR) theory in combination with the first-principles band structure codes allows to calculate phonons in an efficient way. In this report a formalism which enables us to apply LR theory within an all-electron framework utilizing the relativistic full-potential linearized augmented plane-wave (RFLAPW) method is presented. As first part, the equations for the calculations of the atomic forces are given and they are used for the calculation of forces in {alpha}-Pu. As a second step, a complete set of formulaes for the dynamic matrices calculation is presented.
Date: January 8, 2004
Creator: Kutepov, A L
System: The UNT Digital Library
Terascale simulations for heavy ion inertial fusion energy (open access)

Terascale simulations for heavy ion inertial fusion energy

The intense ion beams in a heavy ion Inertial Fusion Energy (IFE) driver and fusion chamber are non-neutral plasmas whose dynamics are largely dominated by space charge. We propose to develop a ''source-to-target'' Heavy Ion Fusion (HIF) beam simulation capability: a description of the kinetic behavior of this complex, nonlinear system which is both integrated and detailed. We will apply this new capability to further our understanding of key scientific issues in the physics of ion beams for IFE. The simulations will entail self-consistent field descriptions that require interprocessor communication, but are scalable and will run efficiently on terascale architectures. This new capability will be based on the integration of three types of simulations, each requiring terascale computing: (1) simulations of acceleration and confinement of the space-charge-dominated ion beams through the driver (accelerator, pulse compression line, and final focusing system) which accurately describe their dynamics, including emittance growth (phase-space dilution) effects; these are particle-in-cell (PIC) models; (2) electromagnetic (EM) and magnetoinductive (Darwin) simulations which describe the beam and the fusion chamber environment, including multibeam, neutralization, stripping, beam and plasma ionization processes, and return current effects; and (3) highly detailed simulations (6f, multispecies PIC, continuum Vlasov), which can examine electron effects …
Date: June 8, 2000
Creator: Friedman, A.; Cohen, R. H.; Grote, D. P.; Sharp, W. M.; Celata, C. M.; Lee, E. P. et al.
System: The UNT Digital Library
Environmental Fate of Organophosphorus Compounds Related to Chemical Weapons (open access)

Environmental Fate of Organophosphorus Compounds Related to Chemical Weapons

Man-made organophosphorus compounds have been widely distributed throughout our environment as pesticides since their development during and after WWII. Many important studies have documented their relative persistence and toxicity. Development and use of some organophosphorus compounds as nerve agents gave rise to a separate but parallel effort to understand environmental persistence. In this latter case, the experiments have focused mainly on evaporation rates and first-order reaction kinetics. However, because organophosphorus compounds are easily polarized, the ionic content of a surrounding media directly factors into these reaction rates, but limited work in this regard has been done under environmentally relevant conditions. Furthermore, limited experiments investigating persistence of these agents on soil has resulted in widely varying degradation rates. Not surprisingly, no studies have investigated affinities of organophosphorus nerve agents to mineral or organic matter typically found in soil. As a result, we initiated laboratory experiments on dilute concentrations of nerve agent O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX) to quantify persistence in simulated environmental aqueous conditions. A quantitative analytical method was developed for VX and its degradation products using High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). VX hydrolysis rate is known to have a pH-dependency, however, the type of buffer and the relative proportion …
Date: February 8, 2005
Creator: Davisson, M L; Love, A H; Vance, A & Reynolds, J G
System: The UNT Digital Library
Final Focus Spot Size in a Solenoid Focusing System (open access)

Final Focus Spot Size in a Solenoid Focusing System

A linear lens can focus a cold beam to a singular point. Unfortunately, this ideal situation would never occur in the real world. Besides nonlinearity of the lens, any deviation of the beam parameters from the ideal beam's nominal beam parameters would lead to nonzero final spot size. In other words, the final spot size of a beam focused by a focusing lens with a given focusing strength depends on its beam parameters, such as the emittance, variations in beam current, energy, envelope and envelope slopes, and nonlinearity of the focusing lens. There are many types of final focusing systems. We consider only the system using a ''thin'' solenoid lens in this notes. Generally, the net focusing force in a solenoid focusing system is not sensitive to the beam current for an emittance dominated beam. For simplicity, we will ignore the space charge forces in the discussion, and focus on the contributions of beam emittance, energy variation and nonlinearity of the lens to the final spot size here.
Date: April 8, 2003
Creator: Chen, Y. J.
System: The UNT Digital Library
Blanket Biological Review for General Maintenance Activities Within Active Burial Grounds, 200 E and 200 W Areas, ECR No.2001-200-048 (open access)

Blanket Biological Review for General Maintenance Activities Within Active Burial Grounds, 200 E and 200 W Areas, ECR No.2001-200-048

No plant and animal species protected under the ESA, candidates for such protection, or species listed by the Washington state government were observed in the vicinity of the proposed sites. Piper's daisy may still occur in some of the burial grounds. This is a Washington State Sensitive plant species, and as such is a Level III resource under the Hanford Site Biological Resources Management Plan. Compensatory mitigation is appropriate for this species when adverse impacts cannot be avoided. The Ecological Compliance Assessment Project (ECAP) staff should consulted prior to the initiation of major work activities within areas where this species has been identified (218-E-12, 218-E-10). The stalked-pod and crouching milkvetch are relatively common throughout 200 West area, therefore even if the few individuals within the active burial grounds are disturbed, it is not likely that the overall local population will be adversely affected. The Watch List is the lowest level of listing for plant species of concern in the State of Washington. No adverse impacts to species or habitats of concern are expected to occur from routine maintenance within the active portions of the 218-W-4C, 218-W-4B, 218-W-3, 218-W-3A, and 218-W-5 burial grounds, as well as the portion of 218-E-12B currently …
Date: May 8, 2002
Creator: Sackschewsky, Michael R.
System: The UNT Digital Library
EVALUATION OF THE MIGRATION POTENTIAL FOR 60Co AND 137Cs AT THE MAINE YANKEE SITE. (open access)

EVALUATION OF THE MIGRATION POTENTIAL FOR 60Co AND 137Cs AT THE MAINE YANKEE SITE.

The objective of this report is to discuss the degree of sorption and desorption of {sup 137}Cs and {sup 60}Co that may be associated with the granite bedrock and the ''popcorn'' cement drain system that underlie the Maine Yankee Containment Foundation. The purpose is to estimate how much retardation of these two radionuclides takes place in groundwater that flows in the near-field of the Containment Foundation, specifically with respect to contamination originating at the PAB Test Pit. Specific concerns revolve around the potential for the contamination originating near the PAB to create a radioactive dose to a hypothetical ''resident farmer'' using a well intercepting this water to exceed 4 millirems/yr.
Date: August 8, 2002
Creator: FUHRMANN,M. SULLIVAN,T.
System: The UNT Digital Library
Magnetically Collimated Energy Transport by Laser Generated Relativistic Electrons (open access)

Magnetically Collimated Energy Transport by Laser Generated Relativistic Electrons

The possibility of fast ignition of thermo-nuclear fusion is stimulating research interest and activity worldwide. Fast ignition (FI) offers significantly higher gain than conventional spark ignition and the high gain opens the way to an efficient fusion energy producing cycle with laser drivers. The key to FI is the efficient transport of energy from a short pulse laser beam, the igniter, to a small ignition spark in compressed deuterium-tritium fuel. The primary candidate process enabling such energy transfer, is the absorption of laser light and its conversion into a beam of relativistic electrons, which heats the spark. Theory has predicted self-induced magnetic collimation of the electron beam, which could enable efficient transport from the absorption point to the ignition spark. Experiments are required to understand this highly complex process which involves currents in the electron beam, which greatly exceed the Alfven current limit6 (at which the Larmor radius of an electron in the magnetic field associated with by the current is smaller than the radius of the beam). Almost complete current compensation by cold electron return current is therefore required. The oppositely directed hot and cold electron flows initiate strong growth of the Weibel instability, which causes the currents to …
Date: February 8, 2001
Creator: Key, M H
System: The UNT Digital Library
Update of Market Assessment for Capturing Water Conservation Opportunities in the Federal Sector (open access)

Update of Market Assessment for Capturing Water Conservation Opportunities in the Federal Sector

This updated market assessment for capturing water conservation opportunities in the Federal sector is based on a new analytical approach that utilizes newly available data and technologies. The new approach fine-tunes the original assessment by using actual Federal water use, which is now tracked by DOE (as compared to using estimated water use). Federal building inventory data is also used to disseminate water use by end-use technology in the Federal sector. In addition, this analysis also examines the current issues and obstacles that face performance contracting of water efficiency projects at Federal sites.
Date: September 8, 2005
Creator: McMordie-Stoughton, Katherine L.; Solana, Amy E.; Elliott, Douglas B.; Sullivan, Gregory P. & Parker, Graham B.
System: The UNT Digital Library
Effects of Fire on Soil Seed Banks on the Hanford Site (open access)

Effects of Fire on Soil Seed Banks on the Hanford Site

The Hanford wildfire in the summer of 2000 destroyed much of the vegetation on the Hanford Site, often resulting in soil erosion and dust storms. The 200 W Area has been affected by dust storms, and a re-vegetation project has been planned for the area to the west, the source of much of the dust. To determine if the seed bank in this area had been damaged by the fire, inhibiting natural re-growth, soil samples were collected from three burned areas and watered to see how much seedling emergence would occur. The soil was then sifted for grass seeds and the seeds examined for signs of fire damage. From this data it was concluded that significant damage to the seed bank probably occurred in the 200 West Expansion Area, and slight damage may have occurred primarily to monocot seeds in the seed banks farther west.
Date: September 8, 2000
Creator: Baker, Sarah E.
System: The UNT Digital Library
Femtosecond Laser Synthesis of Multi-Element Nanocrystals (open access)

Femtosecond Laser Synthesis of Multi-Element Nanocrystals

We studied the conditions under which short-pulsed laser deposited (PLD) stoichiometric multi-element nanocrystals of GaAs,InP,CoPt and Inconel (an alloy of Cr, Fe and Ni) are formed. The properties of the PLD nanoclusters and the irradiated targets were investigated as a function of the laser pulse-length (150 fs-500 ps) and the inert background gas pressure in the synthesis chamber (microTorr to hundreds of Torr). Our results reveal that the formation of stoichiometric GaAs nanocrystals required ablating a GaAs target with a shorter than 25 ps laser in a {ge} 50 miliTorr of inert background pressure. For InP, a mixture of stoichiometric InP and In nanocrystals with an InP/In ratio of {approx} 1 resulted upon ablating an InP target in Ar at 1 Torr. This InP/In ratio increased to {approx} 5 when ablating the InP target in an Ar pressure of 750 Torr. In case of CoPt alloy, the stoichiometry in the target was not reflected in the collected nanocluster films, independent of the background gas pressure. Interestingly, the stoichiometry of the target was found in the collected nanocluster films when an Inconel target was ablated by a femtosecond laser even in vacuum. It is noted that the constituents of Inconel (Cr, …
Date: January 8, 2003
Creator: Dinh, L N; Trelenberg, T; Torralva, B; Stuart, B C & Balooch, M
System: The UNT Digital Library
LLNL Experimental Results on OMEGA: FY'04 (open access)

LLNL Experimental Results on OMEGA: FY'04

Lawrence Livermore National Laboratory (LLNL) conducted approximately 360 shots on Omega in FY04. Approximately half of the shots were devoted to ICF-relevant experiments. These are summarized as follows:
Date: September 8, 2004
Creator: Turner, R E
System: The UNT Digital Library
Microrelay (open access)

Microrelay

Our goals in this project were to (1) develop a new design concept for a high reliability microrelay, (2) build a prototype, and (3) demonstrate high force relay closure in the prototype. During FY1999, we designed a microrelay to meet commercial specifications: 3 g (or 0.03 N) closure force and 30-mA actuation current at less than 0.5 V. Our microrelay not only occupies less than 1 mm{sup 3}--about 1% of the volume of the smallest commercial part--but also its fabrication takes advantage of semiconductor processing, which has the potential to automate microrelay production. Conventional relays are fabricated by assembling many discrete parts. The process includes a number of nonautomated assembly and inspection steps, which increase fabrication cost and limit possible size reductions. Microrelays based on electrostatic forces can be fabricated by thin-film techniques employed in the semiconductor industry; however, the voltages required to make reliable electrical contact in an electrostatic relay significantly increase the cost of the driver. Microrelays based on electromagnetic forces, on the other hand, provide reliable contacts at low voltage. Reliable metal-to-metal contacts require sufficient contact force to plastically deform contact surfaces at asperities-thereby increasing the contact area. On the other hand, contact metallurgy and the gaseous …
Date: September 8, 2000
Creator: Bernhardt, A.; Cooper, G. & Malba, V.
System: The UNT Digital Library
Almost Optimal Interior Penalty Discontinuous Approximations of Symmetric Elliptic Problems on Non-Matching Grids (open access)

Almost Optimal Interior Penalty Discontinuous Approximations of Symmetric Elliptic Problems on Non-Matching Grids

We consider an interior penalty discontinuous approximation for symmetric elliptic problems of second order on non-matching grids in this paper. The main result is an almost optimal error estimate for the interior penalty approximation of the original problem based on the partition of the domain into a finite number of subdomains. Further, an error analysis for the finite element approximation of the penalty formulation is given. Finally, numerical experiments on a series of model second order problems are presented.
Date: August 8, 2001
Creator: Lazarov, R D; Pasciak, J E; Schoberl, J & Vassilevski, P S
System: The UNT Digital Library
Pressure Loads by Gas in an Enclosed Chamber in DYNA3D (open access)

Pressure Loads by Gas in an Enclosed Chamber in DYNA3D

New algorithms that efficiently calculate the volume of a closed chamber are presented in this paper. The current pressure in the enclosed chamber can then be computed, based on the user-specified gas law, from the updated volume and the initial volume and pressure of the chamber. This pressure load function is very useful in modeling common features, such as air pocket, airbag, piston, and gun barrel, in structural analyses.
Date: August 8, 2002
Creator: Lin, J & Badders, D C
System: The UNT Digital Library
Evaluation of the Fate and Transport of Tritium Contaminated Groundwater from the 618-11 Burial Ground (open access)

Evaluation of the Fate and Transport of Tritium Contaminated Groundwater from the 618-11 Burial Ground

Tritium transport simulations were conducted to model the mechanisms associated with dilution, dispersion, and radioactive decay that attenuate the 618-11 tritium plume and limit the risk associated with exposure to the Columbia River and Energy Northwest water supply wells. A comparison of simulated and observed tritium concentrations at two downgradient monitoring wells indicated that the model was a reasonable representation of the tritium concentrations immediately downgradient of the site (699-13-3A) and near the leading edge of the plume (699-13-0A). This good match increased confidence in the conceptual model, its numeric implementation, and ultimately, the validity of predictive simulations of tritium fate and transport. Three release scenarios were investigated to measure the impact of the tritium plume at primary receptor locations under different conditions. The three cases were (1) a pulse release of tritium from the burial ground that was the best fit between observed and simulated tritium concentrations; (2) a continuing, decaying source beneath the burial ground through 2015, the milestone for source removal under the River Corridor Closure Contract; and (3) a pulse release as in the best fit case but at twice the concentration. For the best fit case, the model predicts that the maximum tritium concentration will …
Date: August 8, 2005
Creator: Vermeul, Vince R.; Bergeron, Marcel P.; Dresel, P Evan; Freeman, Eugene J.; Peterson, R E. & Thorne, Paul D.
System: The UNT Digital Library
Vadose Zone Tracer Testing in the UK Sherwood Sandstone: Hydrogeophysical Data Report (open access)

Vadose Zone Tracer Testing in the UK Sherwood Sandstone: Hydrogeophysical Data Report

In 1998 a joint project between the universities of Lancaster and Leeds, funded by the UK Natural Environment Research Council and the UK Environment Agency, was initiated to examine, using geophysical methods, unsaturated flow and transport processes at two purposely developed field sites in the UK Sherwood Sandstone. More recently work by Lancaster university funded by a UK Natural Environment Research Council PhD studentship (awarded to Peter Winship) has continued the investigation at the two sites. This work, so far, has demonstrated: how cross-borehole (borehole to borehole) radar tomography can be used to monitor changes in moisture content in the unsaturated zone due to natural and forced (tracer) inputs (Binley et al., 2001); the evaluation of seasonal variation of moisture content profiles using high-resolution borehole resistivity and radar profiling (Binley et al., 2002a); initial attempts to utilize the geophysical data to develop numerical predictive models of unsaturated flow (Binley et al., 2002b; Binley et al, 2003; Binley and Beven, 2003). In addition, petrophysical models relating geophysical data to hydrological properties have been developed (West et al., 2003). Here we provide a data report on two tracer experiments conducted at one of the field sites. Within the report we describe the …
Date: October 8, 2003
Creator: Binley, A
System: The UNT Digital Library
Preliminary Thoughts on Introducing Structs to SIDL/Babel: White Paper (open access)

Preliminary Thoughts on Introducing Structs to SIDL/Babel: White Paper

In the past 6 months, there has been increased interest in adding something analogous to C structs to the SIDL language and the Babel language interoperability tool [2, 6]. In particular, Rob Armstrong, of the Common Component Architecture [4], said the lack of structs ''is an oft-cited reason that people can't use Babel.'' Because the interest is high and lack of structs is a barrier to Babel adoption, we must carefully consider the current work around, the motivations for structs, the implications of adding structs, and the alternatives for structs in SIDL/Babel. This document provides the background necessary for a discussion of structs in SIDL/Babel. For the purposes of this document, I am going to call the potential new language feature a SIDL struct. The SIDL struct is analogous to a C struct, a Pascal record, or a Fortran 90 (F90) derived data type. It is a collection of data with no methods or behavior associated with it. Each element of the collection has a name and a type. SIDL structs allow for data abstraction, but they do not provide data hiding. All data is public in a SIDL struct.
Date: January 8, 2004
Creator: Epperly, T W
System: The UNT Digital Library
LLNL inductrack progress report - February 99 through November 99 (open access)

LLNL inductrack progress report - February 99 through November 99

None
Date: March 8, 2000
Creator: Tung, L
System: The UNT Digital Library
Recent Applications of SPME in Directed Stockpile Work (FY04) (open access)

Recent Applications of SPME in Directed Stockpile Work (FY04)

Solid Phase Microextraction (SPME) has been used to sample nonnuclear materials for analysis by gas chromatography-mass spectrometry (GC/MS). This report summarizes progress in the areas of individual materials' outgassing signatures, microcompatibility tests and analysis of polar analytes.
Date: November 8, 2004
Creator: Alviso, C; Harvey, C & Vance, A
System: The UNT Digital Library
Lawrence Livermore National Laboratory Probabilistic Seismic Hazard Codes Validation (open access)

Lawrence Livermore National Laboratory Probabilistic Seismic Hazard Codes Validation

Probabilistic Seismic Hazard Analysis (PSHA) is a methodology that estimates the likelihood that various levels of earthquake-caused ground motion will be exceeded at a given location in a given future time-period. LLNL has been developing the methodology and codes in support of the Nuclear Regulatory Commission (NRC) needs for reviews of site licensing of nuclear power plants, since 1978. A number of existing computer codes have been validated and still can lead to ranges of hazard estimates in some cases. Until now, the seismic hazard community had not agreed on any specific method for evaluation of these codes. The Earthquake Engineering Research Institute (EERI) and the Pacific Engineering Earthquake Research (PEER) center organized an exercise in testing of existing codes with the aim of developing a series of standard tests that future developers could use to evaluate and calibrate their own codes. Seven code developers participated in the exercise, on a voluntary basis. Lawrence Livermore National laboratory participated with some support from the NRC. The final product of the study will include a series of criteria for judging of the validity of the results provided by a computer code. This EERI/PEER project was first planned to be completed by June …
Date: February 8, 2003
Creator: Savy, J B
System: The UNT Digital Library
Natural Gas Storage in Basalt Aquifers of the Columbia Basin, Pacific Northwest USA: A Guide to Site Characterization (open access)

Natural Gas Storage in Basalt Aquifers of the Columbia Basin, Pacific Northwest USA: A Guide to Site Characterization

This report provides the technical background and a guide to characterizing a site for storing natural gas in the Columbia River Basalt
Date: August 8, 2002
Creator: Reidel, Steve P.; Spane, Frank A. & Johnson, Vernon G.
System: The UNT Digital Library
Image-Based Vehicle Identification Technology for Homeland Security Applications (open access)

Image-Based Vehicle Identification Technology for Homeland Security Applications

The threat of terrorist attacks against US civilian populations is a very real, near-term problem that must be addressed, especially in response to possible use of Weapons of Mass Destruction. Several programs are now being funded by the US Government to put into place means by which the effects of a terrorist attack could be averted or limited through the use of sensors and monitoring technology. Specialized systems that detect certain threat materials, while effective within certain performance limits, cannot generally be used efficiently to track a mobile threat such as a vehicle over a large urban area. The key elements of an effective system are an image feature-based vehicle identification technique and a networked sensor system. We have briefly examined current uses of image and feature recognition techniques to the urban tracking problem and set forth the outlines of a proposal for application of LLNL technologies to this critical problem. The primary contributions of the proposed work lie in filling important needs not addressed by the current program: (1) The ability to create vehicle ''fingerprints,'' or feature information from images to allow automatic identification of vehicles. Currently, the analysis task is done entirely by humans. The goal is to …
Date: October 8, 2002
Creator: Clark, G. A.
System: The UNT Digital Library
An Application of Trapped-Air Analysis to Large Complex High-Pressure Magnesium Casting (open access)

An Application of Trapped-Air Analysis to Large Complex High-Pressure Magnesium Casting

The usual method for simulating die-castings consists of a solidification analysis of the casting process - a computer calculation of heat transfer between the casting and the die components. The use of cyclic simulations, coupled with the geometric accuracy of the finite element method, has advanced this procedure to the point where it is routinely used for reliable prediction of shrinkage defects in die-castings. Filling analysis is also routinely used to get a glimpse of cavity filling and ensures that overflows are at their most effective location. When coupled with heat transfer, a filling analysis is also very effective in demonstrating the effects of heat loss in the fluid and how it consequentially can negatively affect filling.
Date: July 8, 2004
Creator: Prindiville, J.; Lee, S. & Gokhale, A.
System: The UNT Digital Library