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Algorithm for Wave-Particle Resonances in Fluid Codes - Final Report (open access)

Algorithm for Wave-Particle Resonances in Fluid Codes - Final Report

We review the work performed under LDRD ER grant 98-ERD-099. The goal of this work is to write a subroutine for a fluid turbulence code that allows it to incorporate wave-particle resonances (WPR). WPR historically have required a kinetic code, with extra dimensions needed to evolve the phase space distribution function, f(x, v, t). The main results accomplished under this grant have been: (1) Derivation of a nonlinear closure term for 1D electrostatic collisionless fluid; (2) Writing of a 1D electrostatic fluid code, ''es1f,'' with a subroutine to calculate the aforementioned closure term; (3) derivation of several methods to calculate the closure term, including Eulerian, Euler-local, fully local, linearized, and linearized zero-phase-velocity, and implementation of these in es1f; (4) Successful modeling of the Landau damping of an arbitrary Langmuir wave; (5) Successful description of a kinetic two-stream instability up to the point of the first bounce; and (6) a spin-off project which uses a mathematical technique developed for the closure, known as the Phase Velocity Transform (PVT) to decompose turbulent fluctuations.
Date: March 3, 2000
Creator: Mattor, N.
System: The UNT Digital Library
Conceptual and Numerical Models for UZ Flow and Transport (open access)

Conceptual and Numerical Models for UZ Flow and Transport

The purpose of this Analysis/Model Report (AMR) is to document the conceptual and numerical models used for modeling of unsaturated zone (UZ) fluid (water and air) flow and solute transport processes. This is in accordance with ''AMR Development Plan for U0030 Conceptual and Numerical Models for Unsaturated Zone (UZ) Flow and Transport Processes, Rev 00''. The conceptual and numerical modeling approaches described in this AMR are used for models of UZ flow and transport in fractured, unsaturated rock under ambient and thermal conditions, which are documented in separate AMRs. This AMR supports the UZ Flow and Transport Process Model Report (PMR), the Near Field Environment PMR, and the following models: Calibrated Properties Model; UZ Flow Models and Submodels; Mountain-Scale Coupled Processes Model; Thermal-Hydrologic-Chemical (THC) Seepage Model; Drift Scale Test (DST) THC Model; Seepage Model for Performance Assessment (PA); and UZ Radionuclide Transport Models.
Date: March 3, 2000
Creator: Liu, H.
System: The UNT Digital Library
Discussion Regarding Sources and Ages of Groundwater in Southeastern California (open access)

Discussion Regarding Sources and Ages of Groundwater in Southeastern California

A planned groundwater storage project for future drought relief has been assessed in the Fenner Gap area of the Fenner, Cadiz, and Bristol watershed region of southeastern California. Questions regarding the source and age of groundwater beneath the proposed project area were resolved using natural isotope abundances measured at LLNL. The report presents data, briefly summarizes conclusions of that data, and records correspondence with the sponsor Geosciences Support Services Inc.
Date: March 3, 2000
Creator: Davisson, M.L.
System: The UNT Digital Library
FEMP Fiscal Year 1999 ESPC Business Strategy Development Summary Report (open access)

FEMP Fiscal Year 1999 ESPC Business Strategy Development Summary Report

This report summarizes the objectives, activities, products, and recommendations of the ESPC Business Strategy Development project. The objective of this project was to assist DOE FEMP in defining the potential Federal sector market for FEMP-offered alternative financing services with a focus on Super-Energy Savings Performance Contracts (Super-ESPCs).
Date: March 3, 2000
Creator: McMordie-Stoughton, Katherine L. & Hunt, W. D.
System: The UNT Digital Library
Final Report: Hardening and Strain Localization in Single and Polycrystalline Materials Under Cyclic and Monotonic Deformation, January 11, 1985 - July 31, 1997 (open access)

Final Report: Hardening and Strain Localization in Single and Polycrystalline Materials Under Cyclic and Monotonic Deformation, January 11, 1985 - July 31, 1997

The subject program on substructure evolution initially focused on strain localization produced by fatigue cycling and especially how such localization affects the cyclic response of polycrystalline pure metal. The latter stages have dealt with strain localization in the heavy monotonic deformation of alloys, which eventually produces forms of localized deformation that include coarse slip bands (CSB's), which are aligned to slip planes and macroscopic shear bands (MSB's), which are not aligned to slip planes. These forms of strain localization are important in that they limit the usable ductility of the material in forming processes.
Date: March 3, 2000
Creator: Laird, Campbell & Bassani, John L.
System: The UNT Digital Library
Medicaid Managed Care: Challenges in Implementing Safeguards for Children With Special Needs (open access)

Medicaid Managed Care: Challenges in Implementing Safeguards for Children With Special Needs

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Health Care Financing Administration's (HCFA) and the states' efforts to implement safeguards to protect children with disabilities who are enrolled in Medicaid managed care programs, focusing on the: (1) implications of the Balanced Budget Act of 1997 (BBA) provisions defining this population; (2) number of states enrolling children with special needs in capitated health plans; and (3) steps HCFA has taken to establish appropriate safeguards for this population."
Date: March 3, 2000
Creator: United States. General Accounting Office.
System: The UNT Digital Library
[Mentor Review Document for Teachers and Leadership Teams at Oakhurst School] (open access)

[Mentor Review Document for Teachers and Leadership Teams at Oakhurst School]

A comprehensive mentor review, evaluating the performance and achievements of teachers and leadership teams at Oakhurst School. Through a detailed analysis of set goals, instructional strategies, and collaborative efforts, the document highlights the strengths and areas for improvement identified during the mentorship process.
Date: March 3, 2000
Creator: unknown
System: The UNT Digital Library
Pinochet Extradition Case: Selected Legal Issues (open access)

Pinochet Extradition Case: Selected Legal Issues

None
Date: March 3, 2000
Creator: unknown
System: The UNT Digital Library
PNNL/Euratom glass fiber optic, spent fuel neutron profile measurement system (open access)

PNNL/Euratom glass fiber optic, spent fuel neutron profile measurement system

The glass fiber optic spent fuel neutron profile measurement system is designed to measure the neutron profile of a Castor with high reproducibility and to distinguish spent fuel Castor contents from vitrified waste Castor contents. The basic principle of the detector is that the glass fibers detect thermal neutrons. The glass is loaded with lithium enriched in Li-6, which has a high thermal neutron cross-section. A neutron is captured by the Li-6 and a He-4 and H-3 are created. Because the glass also contains Cerium in a 3{sup +} ionization state, the excitation caused by the movement of the He-4 and H-3 results in the emission of light from the cerium atoms. This light then travels to the ends of the fiber where it is detected by photon sensitive devices (e.g., photo-multiplier tubes).
Date: March 3, 2000
Creator: Bowyer, S. M. & Smart, J. E.
System: The UNT Digital Library
Pulse Capacitors for Next Generation Linear Colliders. Final Report (open access)

Pulse Capacitors for Next Generation Linear Colliders. Final Report

During this Phase I SBIR research program, Nanomaterials Research Corporation (NRC) successfully demonstrated high-voltage multilayer capacitors produced from sub-100 nm ceramic powders. The devices produced by NRC exhibited properties that make them particularly useful for pulse power applications. These properties include (1) high capacitance (2) low loss (3) high breakdown voltage (4) high insulation resistance and (5) rapid discharge characteristics. Furthermore, the properties of the nanostructured capacitors were consistently found to exceed those of components that represent the state of the art within the industry. Encouraged by these results, NRC is planning to submit a Phase II proposal with the objective of securing seed capital to continue this development effort.
Date: March 3, 2000
Creator: Hooker, M. W.
System: The UNT Digital Library
School Facilities: Construction Expenditures Have Grown Significantly in Recent Years (open access)

School Facilities: Construction Expenditures Have Grown Significantly in Recent Years

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed construction expenditures for public school facilities, focusing on: (1) the trends since 1990 in elementary and secondary school construction expenditures and how construction expenditures were divided between land, buildings, and equipment; (2) the trends since 1990 in the amount of expenditures for elementary and secondary school construction by type of school and type of construction; and (3) what is known about the amounts and mix of state and local funding for elementary and secondary school construction."
Date: March 3, 2000
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Trends in Medicare Spending: Fact Sheet (open access)

Trends in Medicare Spending: Fact Sheet

None
Date: March 3, 2000
Creator: Chaikind, Hinda Ripps
System: The UNT Digital Library
U.S.-Mexico Border: Better Planning, Coordination Needed to Handle Growing Commercial Traffic (open access)

U.S.-Mexico Border: Better Planning, Coordination Needed to Handle Growing Commercial Traffic

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the increased trade activity and traffic congestion problems being experienced by the southwest border states, focusing on the: (1) nature of commercial truck traffic congestion at the southwest border; (2) factors that contribute to congestion; and (3) actions, including programs and funding, that are being taken to address these problems."
Date: March 3, 2000
Creator: United States. General Accounting Office.
System: The UNT Digital Library
U.S.-Mexico Border: Despite Some Progress, Environmental Infrastructure Challenges Remain (open access)

U.S.-Mexico Border: Despite Some Progress, Environmental Infrastructure Challenges Remain

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the status of the U.S.-Mexican border environmental infrastructure and the performance of responsible institutions and programs, focusing on the: (1) nature and extent of environmental infrastructure problems along the border; (2) programs and funding levels in place to address these problems; and (3) impediments to improving the environmental infrastructure."
Date: March 3, 2000
Creator: United States. General Accounting Office.
System: The UNT Digital Library
X-Ray Attenuation Cell (open access)

X-Ray Attenuation Cell

To minimize the pulse-to-pulse variation, the LCLS FEL must operate at saturation, i.e. 10 orders of magnitude brighter spectral brilliance than 3rd-generation light sources. At this intensity, ultra-high vacuums and windowless transport are required. Many of the experiments, however, will need to be conducted at a much lower intensity thereby requiring a reliable means to reduce the x-ray intensity by many orders of magnitude without increasing the pulse-to-pulse variation. In this report we consider a possible solution for controlled attenuation of the LCLS x-ray radiation. We suggest using for this purpose a windowless gas-filled cell with the differential pumping. Although this scheme is easily realizable in principle, it has to be demonstrated that the attenuator can be made short enough to be practical and that the gas loads delivered to the vacuum line of sight (LOS) are acceptable. We are not going to present a final, optimized design. Instead, we will provide a preliminary analysis showing that the whole concept is robust and is worth further study. The spatial structure of the LCLS x-ray pulse at the location of the attenuator is shown in Fig. 1. The central high-intensity component, due to the FEL, has a FWHM of {approx}100 {micro}m. …
Date: March 3, 2000
Creator: Ryutov, D. & Toor, A.
System: The UNT Digital Library
San Antonio Monthly Reports: February 2001 (open access)

San Antonio Monthly Reports: February 2001

Compilation of monthly reports from departments in the city of San Antonio, Texas providing statistics, project updates, and other information about services and activities.
Date: March 3, 2001
Creator: San Antonio (Tex.)
System: The Portal to Texas History
Hybrid Finite Element-Fast Spectral Domain Multilayer Boundary Integral Modeling of Doubly Periodic Structures (open access)

Hybrid Finite Element-Fast Spectral Domain Multilayer Boundary Integral Modeling of Doubly Periodic Structures

Hybrid finite element (FE)--boundary integral (BI) analysis of infinite periodic arrays is extended to include planar multilayered Green's functions. In this manner, a portion of the volumetric dielectric region can be modeled via the finite element method whereas uniform multilayered regions can be modeled using a multilayered Green's function. As such, thick uniform substrates can be modeled without loss of efficiency and accuracy. The multilayered Green's function is analytically computed in the spectral domain and the resulting BI matrix-vector products are evaluated via the fast spectral domain algorithm (FSDA). As a result, the computational cost of the matrix-vector products is kept at O(N). Furthermore, the number of Floquet modes in the expansion are kept very few by placing the BI surfaces within the computational unit cell. Examples of frequency selective surface (FSS) arrays are analyzed with this method to demonstrate the accuracy and capability of the approach. One example involves complicated multilayered substrates above and below an inhomogeneous filter element and the other is an optical ring-slot array on a substrate several hundred wavelengths in thickness. Comparisons with measurements are included.
Date: March 3, 2002
Creator: Eibert, T.F.; Volakis, J.L. & Erdemli, Y.E.
System: The UNT Digital Library
2002 status report: Savings estimates for the ENERGY STAR(R) voluntary labeling program (open access)

2002 status report: Savings estimates for the ENERGY STAR(R) voluntary labeling program

ENERGY STAR [registered trademark] is a voluntary labeling program designed to identify and promote energy-efficient products, buildings and practices. Operated jointly by the Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE), ENERGY STAR labels exist for more than thirty products, spanning office equipment, residential heating and cooling equipment, commercial and residential lighting, home electronics, and major appliances. This report presents savings estimates for a subset of ENERGY STAR program activities, focused primarily on labeled products. We present estimates of the energy, dollar and carbon savings achieved by the program in the year 2001, what we expect in 2002, and provide savings forecasts for two market penetration scenarios for the period 2002 to 2020. The target market penetration forecast represents our best estimate of future ENERGY STAR savings. It is based on realistic market penetration goals for each of the products. We also provide a forecast under the assumption of 100 percent market penetration; that is, we assume that all purchasers buy ENERGY STAR-compliant products instead of standard efficiency products throughout the analysis period.
Date: March 3, 2003
Creator: Webber, Carrie A.; Brown, Richard E.; McWhinney, Marla & Koomey, Jonathan
System: The UNT Digital Library
The 237U(n,f) Cross Section (open access)

The 237U(n,f) Cross Section

The purpose of this note is to combine existing information on the {sup 237}U(n,f) cross section to determine if some consistency can be obtained for the neutron induced fission excitation of {sup 237}U. The neutron induced fission cross section of the 6.8 day {sup 237}U was measured directly by McNally et al. in 1968 using the Pommard nuclear device test. At the same time critical assembly measurements were done at Los Alamos using the Flattop assembly. A previous measurement was also made at LASL in 1954 with two different neutron sources, each peaked near 200 keV. The results were 0.66 {+-} 0.10 b and 0.70 {+-} 0.07 b for the (n,f) cross section. More recently Younes and Britt have reanalyzed direct reaction charged particle data of Cramer and Britt that had determined the fission probability of the {sup 238}U compound nucleus as a function of nuclear excitation energy. They have combined fission probabilities with calculated neutron absorption cross sections, including corrections for the differences in angular momentum between the direct and neutron induced reactions. From this analysis they have extracted equivalent {sup 237}U(n,f) cross sections. The technique for extracting surrogate (n,f) cross sections from (t,pf) data has been demonstrated in …
Date: March 3, 2003
Creator: Younes, W.; Britt, H. C. & Wilhelmy, J. B.
System: The UNT Digital Library
AIDS in Africa (open access)

AIDS in Africa

Sub-Saharan Africa has been far more severely affected by AIDS than any other part of the world. The United Nations reports that 25.3 million adults and children are infected with the HIV virus in the region, which has about 10% of the world's population but more than 70% of the worldwide total of infected people. This report discusses this issue in detail, including the cause of the African AIDS epidemic, the social and economic consequences, response and treatment, and U.S. policy.
Date: March 3, 2003
Creator: Copson, Raymond W.
System: The UNT Digital Library
Chemical-Kinetic Characterization of Autoignition and Combustion of Surrogate Diesel (open access)

Chemical-Kinetic Characterization of Autoignition and Combustion of Surrogate Diesel

A study was performed to elucidate the chemical-kinetic mechanism of combustion of toluene. The research was performed in collaboration Dr. Charles Westbrook and Dr. William Pitz at Lawrence Livermore National Laboratory (LLNL). A detailed chemical-kinetic mechanism for toluene developed at LLNL was employed. Numerical calculations were performed using this mechanism and the results were compared with experimental data obtained from premixed and nonpremixed systems. Under premixed conditions, predicted ignition delay times were compared with new experimental data obtained by I. Da Costa, R. Fournet, F. Billaud, F. Battin-Leclerc at Departement de Chime Physique des Reactions, CNRS-ENSIC, BP. 451, 1, rue Grandville, 51001 Nancy, France. Also, calculated species concentration histories were compared to experimental flow reactor data from the literature. Under nonpremixed conditions, critical conditions of extinction and autoignition were measured in strained laminar flows in the counterflow configuration. Numerical calculations were performed using the chemical-kinetic mechanism at conditions corresponding to those in the experiments. Critical conditions of extinction and autoignition are predicted and compared with the experimental data. Comparisons between the model predictions and experimental results of ignition delay times in shock tube, and extinction and autoignition in nonpremixed systems show that the chemical-kinetic mechanism predicts that toluene/air is overall …
Date: March 3, 2003
Creator: Seshadri, K
System: The UNT Digital Library
Child Welfare Issues in the 108th Congress (open access)

Child Welfare Issues in the 108th Congress

The purpose of this report is to present a number of generally less broad legislative proposals related to child welfare financing have been introduced in the 108th Congress. Additional child welfare-related proposals designed to improve services, promote timely placement of children across state lines, and for other purposes, are described in this report.
Date: March 3, 2003
Creator: Stoltzfus, Emilie
System: The UNT Digital Library
Clean Air Act Issues in the 108th Congress (open access)

Clean Air Act Issues in the 108th Congress

Clean air issues were discussed at length in the 107th Congress, but legislation was not enacted, leaving the same issues for possible consideration in the 108th. The most prominent air quality issues discussed in this report are; the controversy over EPA’s proposed changes to the New Source Review (NSR) requirements, Clear Skies / Multi-Pollutant Legislation, gasoline additive MTBE, Conformity of Transportation Plans and SIPs Deadlines for Achieving the Ozone Air Quality Standard.
Date: March 3, 2003
Creator: McCarthy, James E.
System: The UNT Digital Library
Compendium of Regulatory Requirements Governing Underground Injection of Drilling Wastes (open access)

Compendium of Regulatory Requirements Governing Underground Injection of Drilling Wastes

This report provides a comprehensive compendium of the regulatory requirements governing the injection processes used for disposing of drilling wastes; in particular, for a process referred to in this report as slurry injection. The report consists of a narrative discussion of the regulatory requirements and practices for each of the oil- and gas-producing states, a table summarizing the types of injection processes authorized in each state, and an appendix that contains the text of many of the relevant state regulations and policies.
Date: March 3, 2003
Creator: Puder, Markus G.; Bryson, Bill & Veil, John A.
System: The UNT Digital Library