States

Agricultural Marketing Assistance Loans and Loan Deficiency Payments (open access)

Agricultural Marketing Assistance Loans and Loan Deficiency Payments

This report discusses marketing assistance loans for major crops. The debate surrounds enlarging the program to create further farm income support.
Date: December 13, 2000
Creator: Womach, Jasper
Object Type: Report
System: The UNT Digital Library
Agricultural Marketing Assistance Loans and Loan Deficiency Payments (open access)

Agricultural Marketing Assistance Loans and Loan Deficiency Payments

Marketing assistance loans for the major crops were designed to facilitate orderly marketing by providing short-term financing so that farmers could pay their bills right after harvest and spread their sales over the entire marketing year. However, the persistence of very low commodity prices transformed the loan program into a major vehicle of farm income support. Marketing loan program benefits (primarily loan deficiency payments, LDPs) to farmers amounted to about $5.9 billion in 1999, and will exceed $6.5 billion in 2000. Such levels of use and high costs have revealed several administrative problems and given rise to several policy issues. Some policy makers have favored broadening the scope and enhancing the benefits of the program to achieve greater farm income support. Anticipated adverse market impacts have discouraged adoption of these proposals to date. A persistent policy issue is the payment limitation on marketing loan gains.
Date: December 13, 2000
Creator: Womach, Jasper
Object Type: Report
System: The UNT Digital Library
Antiguided Ribbon Laser Concept (open access)

Antiguided Ribbon Laser Concept

We propose a new, robustly scalable technique for phase locking multiple gain cores in a fiber structure based on antiguiding or radiative coupling, rather than the more commonly pursued method of evanescent wave phase locking. Our focus is on a ribbon-like geometry in which a waveguide region contains multiple gain cores arranged in a periodic array. The distinguishing feature of such antiguiding structures is that refractive index of the gain cores is lower than or equal to that of the surrounding waveguide regions. This is just the opposite of evanescently phase locked structures in which the gain cores have higher refractive index than the surrounding regions. The critical design considerations in the structures proposed within are: first that they strongly favor oscillation in a single transverse mode, and second that this strongly favored mode exhibits good intensity uniformity across the entire array of gain cores. We require single mode operation so that a static phase corrector placed in the near field of the ribbon laser's output can optimize the phase across the aperture to achieve a high Strehl ratio in the far field. The requirement that the strongly favored mode exhibit good uniformity across the entire array of gain cores …
Date: December 13, 2000
Creator: Beach, R; Feit, M; Page, R; Brasure, L; Wilcox, R & Payne, S
Object Type: Report
System: The UNT Digital Library
Electoral Vote Counts in Congress: Survey of Certain Congressional Practices (open access)

Electoral Vote Counts in Congress: Survey of Certain Congressional Practices

This report surveys certain aspects of the historical congressional practice in counting the presidential electoral votes in Congress.
Date: December 13, 2000
Creator: Maskell, Jack; Halstead, T. J. & Welborn, Angie
Object Type: Report
System: The UNT Digital Library
Exploring old and new benzene formation pathways in low-pressure premixed flames of aliphatic fuels (open access)

Exploring old and new benzene formation pathways in low-pressure premixed flames of aliphatic fuels

A modeling study of benzene and phenyl radical formation is performed for three low-pressure premixed laminar flat flames having an unsaturated C{sub 2} or C{sub 3} hydrocarbon fuel (acetylene, ethylene, and propene). Predictions using three published detailed elementary-step chemical kinetics mechanisms are tested against MBMS species profile data for all three flames. The differences between the three mechanisms predictive capabilities are explored, with an emphasis on benzene formation pathways. A new chemical kinetics mechanism is created combining features of all three published mechanisms. Included in the mechanism are several novel benzene formation reactions involving combinations of radicals such as C{sub 2}H+C{sub 4}H{sub 5}, and C{sub 5}H{sub 3}+CH{sub 3}. Reactions forming fulvene (a benzene isomer) are included, such as C{sub 3}H{sub 3}+C{sub 3}H{sub 5},as well as fulvene-to-benzene reactions. Predictions using the new mechanism show virtually all of the benzene and phenyl radical to be formed by reactions of either C{sub 3}H{sub 3}+C{sub 3}H{sub 3} or C{sub 3}H{sub 3}+C{sub 3}H{sub 5}, with the relative importance being strongly dependent upon the fuel. C{sub 5}H{sub 3}+CH{sub 3} plays a minor role in fulvene formation in the acetylene flame. The C{sub 2}H{sub x}+C{sub 4}H{sub 4} reactions do not contribute noticeably to benzene or phenyl radical …
Date: December 13, 2000
Creator: Pope, Christopher J. & Miller, James A.
Object Type: Article
System: The UNT Digital Library
Financial Management: Navy's Implementation of the Defense Property Accountability System (open access)

Financial Management: Navy's Implementation of the Defense Property Accountability System

Correspondence issued by the General Accounting Office with an abstract that begins "As part of its involvement with the Navy Personal Property Working Group, GAO reviewed the Department of the Navy's implementation of the Defense Property Accountability System (DPAS). As requested by the working group, GAO visited six Navy activities to evaluate DPAS implementation at those selected locations. GAO found that (1) physical wall-to-wall inventories of personal property were not being done properly; (2) personal property items were not being included in DPAS at a component level to ensure accountability; and (3) policies, procedures, and training were not in place to ensure the sustainability of the property database."
Date: December 13, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
GEOCHEMISTRY OF ROCK UNITS AT THE POTENTIAL REPOSITORY LEVEL, YUCCA MOUNTAIN, NEVADA (open access)

GEOCHEMISTRY OF ROCK UNITS AT THE POTENTIAL REPOSITORY LEVEL, YUCCA MOUNTAIN, NEVADA

The compositional variability of the phenocryst-poor member of the 12.8-million-year Topopah Spring Tuff at the potential repository level was assessed by duplicate analysis of 20 core samples from the cross drift at Yucca Mountain, Nevada. Previous analyses of outcrop and core samples of the Topopah Spring Tuff showed that the phenocryst-poor rhyolite, which includes both lithophysal and nonlithophysal zones, is relatively uniform in composition. Analyses of rock samples from the cross drift, the first from the actual potential repository block, also indicate the chemical homogeneity of this unit excluding localized deposits of vapor-phase minerals and low-temperature calcite and opal in fractures, cavities, and faults, The possible influence of vapor-phase minerals and calcite and opal coatings on rock composition at a scale sufficiently large to incorporate these heterogeneously distributed deposits was evaluated and is considered to be relatively minor. Therefore, the composition of the phenocryst-poor member of the Topopah Spring Tuff is considered to be adequately represented by the analyses of samples from the cross drift. The mean composition as represented by the 10 most abundant oxides in weight percent or grams per hundred grams is: SiO{sub 2}, 76.29; Al{sub 2}O{sub 3}, 12.55; FeO, 0.14; Fe{sub 2}O{sub 3}, 0.97; MgO, 0.13; …
Date: December 13, 2000
Creator: Peterman, Z.E. & Cloke, P.L.
Object Type: Report
System: The UNT Digital Library
Hexahedral Mesh Untangling (open access)

Hexahedral Mesh Untangling

We investigate a well-motivated mesh untangling objective function whose optimization automatically produces non-inverted elements when possible. Examples show the procedure is highly effective on simplicial meshes and on non-simplicial (e.g., hexahedral) meshes constructed via mapping or sweeping algorithms. The current whisker-weaving (WW) algorithm in CUBIT usually produces hexahedral meshes that are unsuitable for analyses due to inverted elements. The majority of these meshes cannot be untangled using the new objective function. The most likely source of the difficulty is poor mesh topology.
Date: December 13, 2000
Creator: Knupp, Patrick
Object Type: Article
System: The UNT Digital Library
Middle East: Domestic Politics and the Peace Process – Proceedings of a CRS Seminar (open access)

Middle East: Domestic Politics and the Peace Process – Proceedings of a CRS Seminar

None
Date: December 13, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Multigrid algorithms for solving the linear Boltzmann equation using first-order system least-squares finite element methods (open access)

Multigrid algorithms for solving the linear Boltzmann equation using first-order system least-squares finite element methods

Solving the linear Boltzmann equation in neutron scattering phenomena presents many challenges to standard numerical schemes in computational physics. For an SN discretization, the so-called ray effects pollute the numerical solution. This pollution can be viewed mathematically as ''contamination'' from a poorly chosen approximating basis set for the angle component of the discretization-i.e., collocation in angle is equivalent to discretization with delta basis functions, which form a poor approximating basis set. Fortunately, a PN discretization, which uses a better approximating basis set (i.e., spherical harmonics), eliminates these ray effects. Unfortunately, solving for the moments or PN equations is difficult. Moments couple strongly with each other, creating a strongly coupled system of partial differential equations (pde's) ; numerical algorithms for solving such strongly coupled systems are difficult to develop. In this paper, novel algorithms for solving this coupled system are presented. In particular, algorithms for solving the PN discretization of the linear Boltzmann equation using a first-order system least-squares (FOSLS) methodology (c.f. [1]) are presented.
Date: December 13, 2000
Creator: Chang, B. & Lee, B.
Object Type: Article
System: The UNT Digital Library
Observations Concerning the Injection of a Lithium Aerosol into the Edge of TFTR Discharges (open access)

Observations Concerning the Injection of a Lithium Aerosol into the Edge of TFTR Discharges

A new method of actively modifying the plasma-wall interaction was tested on the Tokamak Fusion Test Reactor. A laser was used to introduce a directed lithium aerosol into the discharge scrape-off layer. The lithium introduced in this fashion ablated and migrated preferentially to the limiter contact points. This allowed the plasma-wall interaction to be influenced in situ and in real time by external means. Significant improvement in energy confinement and fusion neutron production rate as well as a reduction in the plasma Zeff have been documented in a neutral-beam-heated plasma. The introduction of a metallic aerosol into the plasma edge increased the internal inductance of the plasma column and also resulted in prompt heating of core electrons in Ohmic plasmas. Preliminary evidence also suggests that the introduction of an aerosol leads to both edge poloidal velocity shear and edge electric field shear.
Date: December 13, 2000
Creator: Mansfield, D.K.; Johnson, D.W.; Grek, B.; Kugel, H.; Bell, M.G. & al, et
Object Type: Report
System: The UNT Digital Library
PCMDI analysis of candidate atmospheric models for CCSM (open access)

PCMDI analysis of candidate atmospheric models for CCSM

This report is intended to give a summary analysis of the candidate model configurations under consideration by NCAR for the atmospheric component of next version of the Community Climate System Model (CCSM). Intercomparison results are presented for each of the models available prior to the Atmospheric Model Working Group (AMWG) meeting, December 12-14, 2000. We present four types of figures in this report. The traditional methods of viewing zonal mean surface fields, latitude-longitude maps and zonal mean latitude-height cross sections are straightforward. In each of these cases, we present DJF and JJA climatological averages and a difference from an observational or reanalysis data set. The fourth method of analyzing the candidates' model performance involves the use of ''performance portraits'' and is explained in detail on following pages. As stated by NCAR and the AMWG, the information included in this report should be considered proprietary to NCAR and is not to be cited, consistent with the disclaimer on the AMWG password protected web pages. We deliberately have deferred our conclusions in this printed report to our presentation. Rather, we encourage you to draw your own conclusions based on these figures and other information made available at the AMWG meeting.
Date: December 13, 2000
Creator: Wehner, M. F.; Taylor, K.; Doutriaux, C.; AchutaRao, K.; Gleckler, P.; Hnilo, J. et al.
Object Type: Article
System: The UNT Digital Library
Progress report on DOE research project [Thermodynamic and kinetic behavior of systems with intermetallic and intermediate phases] (open access)

Progress report on DOE research project [Thermodynamic and kinetic behavior of systems with intermetallic and intermediate phases]

A theoretical investigation was made of the coherent displacive phase transformation between two equilibrium single-phase states producing several orientation variants of the product phase. The research was focused on a behavior of coherent systems (martensitic systems, metal and ceramic, and ferroelectric systems) with defects. The computer simulation demonstrated that randomly distributed static defects may drastically affect the thermodynamics, kinetics, and morphology of the transformation. In particular, the interaction of the transformation mode with the defects may be responsible for appearance of two new fields in the phase diagram: (i) the two-phase field describing the tweed microstructure, which consists of the retain parent phase and the variants of the product phase and (ii) the single-phase field describing the tweed microstructure, which consists of the variants of the product phase. These new fields can be attributed to the pre-transitional states observed in some of th e displacive transformations. The microstructure evolution resulting in formation of the thermoelastic equilibrium is path dependent. This unusual behavior is expected in systems with a sharp dependence of the transition temperature on the defect concentration.
Date: December 13, 2000
Creator: Tsakalakos, T.; Semenovskaya-Khachaturyan, S. & Khachaturyan, A.G.
Object Type: Report
System: The UNT Digital Library
Quantifying Silica Reactivity in Subsurface Environments: Reaction Affinity and Solute Matrix Controls on Quartz and SiO2 Glass Dissolution Kinetics (open access)

Quantifying Silica Reactivity in Subsurface Environments: Reaction Affinity and Solute Matrix Controls on Quartz and SiO2 Glass Dissolution Kinetics

During the three years of this project, Professor Dove's laboratory made tremendous progress in understanding controls on amorphous silica dissolution kinetics in aqueous solutions. Our findings have already received considerable attention. In hydrothermal and low temperature studies, the work focused on determining quantitative and mechanistic controls on the most abundant silica polymorphs in Earth environments--quartz and amorphous silica. Our studies achieved goals set forth in the original proposal to establish a new quantitative understanding of amorphous silica dissolution. This support has resulted in 10 journal, 12 abstracts and 2 thesis publications. The PI and students were also recognized with 6 awards during this period. The 1998 EMSP conference in Chicago was an important meeting for our project. The symposium, enabled P.I. Dove to establish valuable contacts with ''users'' having specific needs for the findings of our EMSP project related to the urgency of problems in the Tanks Focus Area (TFA). Since that time, our working relations developed as Dove interacted with TFA scientists and engineers on the problems of waste glass properties. These interactions refined our experimental objectives to better meet their needs. Dove presented the results of EMSP research findings to a TFA subgroup at a Product Acceptance Workshop …
Date: December 13, 2000
Creator: Dove, Patricia M.
Object Type: Report
System: The UNT Digital Library
Quantitative Temperature Imaging in Gas-Phase Turbulent Thermal Convection by Laser-Induced Fluorescence of Acetone (open access)

Quantitative Temperature Imaging in Gas-Phase Turbulent Thermal Convection by Laser-Induced Fluorescence of Acetone

In this paper, an acetone planar laser-induced fluorescence (PLIF) technique for nonintrusive, temperature imaging is demonstrated in gas-phase (Pr = 0.72) turbulent Rayleigh-Benard convection at Rayleigh number, Ra = 1.3 x 10{sup 5}. The PLIF technique provides quantitative, spatially correlated temperature data without the flow intrusion or time lag associated with physical probes and without the significant path averaging that plagues most optical heat-transfer diagnostic tools, such as the Mach-Zehnder interferometer, thus making PLIF an attractive choice for quantitative thermal imaging in easily perturbed, complex three-dimensional flow fields. The instantaneous (20-ns integration time) thermal images presented have a spatial resolution of 176 x 176 x 500 {micro}m and a single-pulse temperature measurement precision of {+-}5.5 K, or 5.4 % of the total temperature difference. These images represent a 2-D slice through a complex, 3-D flow allowing for the thermal structure of the turbulence to be quantified. Statistics such as the horizontally averaged temperature profile, rms temperature fluctuation, two-point spatial correlations, and conditionally averaged plume structures are computed from an ensemble of 100 temperature images. The profiles of the mean temperature and rms temperature fluctuation are in good agreement with previously published data, and the results obtained from the two-point spatial …
Date: December 13, 2000
Creator: KEARNEY,SEAN P. & REYES,FELIPE V.
Object Type: Article
System: The UNT Digital Library
Risk Assessment Methodology for Protecting Our Critical Physical Infrastructures (open access)

Risk Assessment Methodology for Protecting Our Critical Physical Infrastructures

Critical infrastructures are central to our national defense and our economic well-being, but many are taken for granted. Presidential Decision Directive (PDD) 63 highlights the importance of eight of our critical infrastructures and outlines a plan for action. Greatly enhanced physical security systems will be required to protect these national assets from new and emerging threats. Sandia National Laboratories has been the lead laboratory for the Department of Energy (DOE) in developing and deploying physical security systems for the past twenty-five years. Many of the tools, processes, and systems employed in the protection of high consequence facilities can be adapted to the civilian infrastructure.
Date: December 13, 2000
Creator: BIRINGER,BETTY E. & DANNEELS,JEFFREY J.
Object Type: Article
System: The UNT Digital Library
Site Selection for Surplus Plutonium Disposition Facilities at the Savannah River Site (open access)

Site Selection for Surplus Plutonium Disposition Facilities at the Savannah River Site

The purpose of this study is to identify, assess, and rank potential sites for the proposed Surplus Plutonium Disposition Facilities complex at the Savannah River Site.
Date: December 13, 2000
Creator: Wike, L. D.
Object Type: Report
System: The UNT Digital Library
State Department: Serious Problems in the Anthrax Vaccine Immunization Program (open access)

State Department: Serious Problems in the Anthrax Vaccine Immunization Program

A letter report issued by the General Accounting Office with an abstract that begins "In 1998, the State Department stockpiled anthrax vaccine and antibiotics at several diplomatic posts near Iraq. In the event of an anthrax attack by Iraq, this stockpile was to be used for post-exposure immunization and treatment. In 1999, the State announced that it was starting a voluntary Anthrax Immunization Program for U.S. government employees, their dependents, and other personnel overseas. According to the Food and Drug Administration (FDA), full pre-exposure protection from anthrax requires six vaccinations given over an 18-month period, followed by an annual booster. Because the supplies of vaccines approved by FDA were insufficient, State decided to suspend plans to expand the program beyond the pilot site until more vaccine was available. GAO found that both the State Department's prepositioning of anthrax vaccine at diplomatic missions and the voluntary anthrax immunization program have been poorly implemented. Specifically, the vaccine was not properly stored or refrigerated, requirements for the voluntary program were not accurately estimated, and surveillance procedures used in the pilot program to monitor reactions to the vaccine were inadequate."
Date: December 13, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Statistical Properties of Antenna Impedance in an Electrically Large Cavity (open access)

Statistical Properties of Antenna Impedance in an Electrically Large Cavity

This paper presents models and measurements of antenna input impedance in resonant cavities at high frequencies.The behavior of input impedance is useful in determining the transmission and reception characteristics of an antenna (as well as the transmission characteristics of certain apertures). Results are presented for both the case where the cavity is undermoded (modes with separate and discrete spectra) as well as the over moded case (modes with overlapping spectra). A modal series is constructed and analyzed to determine the impedance statistical distribution. Both electrically small as well as electrically longer resonant and wall mounted antennas are analyzed. Measurements in a large mode stirred chamber cavity are compared with calculations. Finally a method based on power arguments is given, yielding simple formulas for the impedance distribution.
Date: December 13, 2000
Creator: WARNE,LARRY K.; LEE,KELVIN S.H.; HUDSON,H. GERALD; JOHNSON,WILLIAM A.; JORGENSON,ROY E. & STRONACH,STEPHEN L.
Object Type: Article
System: The UNT Digital Library
A theoretical analysis of the reaction between ethyl and molecular oxygen (open access)

A theoretical analysis of the reaction between ethyl and molecular oxygen

Using a combination of electronic-structure theory, variational transition-state theory, and solutions to the time-dependent master equation, the authors have studied the kinetics of the title reaction theoretically over wide ranges of temperature and pressure. The agreement between theory and experiment is quite good. By comparing the theoretical and experimental results describing the kinetic behavior, they have been able to deduce a value for the C{sub 2}H{sub 5}-O{sub 2} bond energy of {approximately}34 kcal/mole and a value for the exit-channel transition-state energy of {minus}4.3 kcal/mole (measured from reactants). These numbers compare favorably with the electronic-structure theory predictions of 33.9 kcal/mole and {minus}3.0 kcal/mole, respectively. The master-equation solutions show three distinct temperature regimes for the reaction, discussed extensively in the paper. Above T {approx} 700 K, the reaction can be written as an elementary step, C{sub 2}H{sub 5} + O{sub 2} {leftrightarrow} C{sub 2}H{sub 4} + HO{sub 2}, with the rate coefficient, k(T) = 3.19 x 10{sup {minus}17} T{sup 1.02} exp(2035/RT) cm{sup 3}/molec.-sec., independent of pressure even though the intermediate collision complex may suffer a large number of collisions.
Date: December 13, 2000
Creator: Miller, James A.; Klippenstein, Stephen J. & Robertson, Stuart H.
Object Type: Article
System: The UNT Digital Library
Wind resource mapping of the state of Vermont (open access)

Wind resource mapping of the state of Vermont

This paper summarizes the results of a wind mapping project and a validation study for the state of Vermont. The computerized wind resource mapping technique used for this project was developed at the National Renewable Energy Laboratory (NREL). The technique uses Geographic Information System (GIS) software and produces high resolution (1km{sup 2}) wind resource maps.
Date: December 13, 2000
Creator: Elliott, D.; Schwartz, M. & Nierenberg, R.
Object Type: Article
System: The UNT Digital Library
Conical Emission Properties Associated with Atmospheric Self-Focussing Femtosecond Pulse Propagation (open access)

Conical Emission Properties Associated with Atmospheric Self-Focussing Femtosecond Pulse Propagation

None
Date: November 13, 2000
Creator: LUK,TING S.; NELSON,THOMAS R. & CAMERON,STEWART M.
Object Type: Article
System: The UNT Digital Library
Diagnosing Plasma Gradients Using Spectral Line Shapes (open access)

Diagnosing Plasma Gradients Using Spectral Line Shapes

The development of a set of stable implosions using indirectly driven plastic microspheres with argon (0.1 atm) doped deuterium (50 atm) has provided a unique source for testing the plasma spectroscopy of the high energy density imploded core. The core reaches electron densities of > 10{sup 24} cm{sup -3} with temperatures of {approx} 1 keV and has been shown to be reproducible on a shot to shot basis. Moreover, it has been shown that not only the peak temperature and density are consistent, but that the temporal evolution of the mean temperature and density of the final phase of the implosion is also reproducible. These imploding cores provide a unique opportunity to test aspects of plasma spectroscopy that are difficult to study in other plasmas and to develop methods to test stable hydrodynamics. We present experimental results and discuss spectroscopic analysis algorithms to determine consistent temperature and density fits to determine gradients in the plasma.
Date: November 13, 2000
Creator: Back, C. A.; Golovkin, I.; Mancini, R.; Missalla, T.; Landen, O. L.; Lee, R. W. et al.
Object Type: Article
System: The UNT Digital Library
Effect of Pressure Transmission Lines on the Frequency Response of Pressure Transducers (open access)

Effect of Pressure Transmission Lines on the Frequency Response of Pressure Transducers

It is well known that the length and diameter of the transmission lines between a pressure transducer and the pressure source can significantly affect the dynamic frequency response of the transducer. A new lumped parameter model has been developed to predict the time and frequency response of any number of different transducers connected in parallel in a manifold. While the model is simple to apply, it can provide quantitative information given the transducer and transmission line characteristic parameters. More importantly, the model can be used to evaluate the measured, in-situ response. this provides the natural frequency and the effective damping which can then be used to generate a frequency response curve. The model is also useful for designing a new pressure transmission system, which will have the required frequency response. The model was qualified by comparison to measurements of the step-function pressure response of a number of different transducers and test installations. With the aid of the model, the system resonant frequency and damping can be determined. Additional damping can be added if necessary to prevent ringing of the signal and to assure an accurate pressure measurement with a flat frequency response. For all of the experimental systems evaluated in …
Date: November 13, 2000
Creator: Kirouac, G.J.
Object Type: Report
System: The UNT Digital Library