Border Security and Unmanned Aerial Vehicles (open access)

Border Security and Unmanned Aerial Vehicles

The use of Unmanned Aerial Vehicles (UAVs) to improve border security is a technique that has garnered congressional attention. This report examines the strengths and limitations of deploying UAVs along the borders and related issues for Congress. This report is not intended to provide in-depth information regarding technical or military capabilities of UAVs, but to discuss their application at the border.
Date: January 2, 2004
Creator: Blazakis, Jason
Object Type: Report
System: The UNT Digital Library
COLAs for Military Retirees: Summary of Congressional and Executive Branch Action, 1982-2003 (FY1983-FY2004) (open access)

COLAs for Military Retirees: Summary of Congressional and Executive Branch Action, 1982-2003 (FY1983-FY2004)

None
Date: January 2, 2004
Creator: Goldich, Robert L.
Object Type: Report
System: The UNT Digital Library
COLAs for Military Retirees: Summary of Congressional and Executive Branch Action, 1982-2003 (FY1983-FY2004) (open access)

COLAs for Military Retirees: Summary of Congressional and Executive Branch Action, 1982-2003 (FY1983-FY2004)

The Omnibus Reconciliation Act of 1982 (which applied to FY1983 budget issues) suspended previously existing permanent law pertaining to cost-of-living adjustments(COLAs) for federal civilian and military retirees, and changed the COLA calculation formulas to postpone and/or reduce future COLAs for military retirees during 1983-1985 (FY1984-FY1986).This report examines executive and congressional COLA-related initiatives associated with each of the fiscal year budgeting processes from calendar year 1982 (FY1983) through calendar year 2000 (FY2001).
Date: January 2, 2004
Creator: Goldich, Robert L.
Object Type: Report
System: The UNT Digital Library
Comparison of Wide-Bandgap Semiconductors for Power Electronics Applications (open access)

Comparison of Wide-Bandgap Semiconductors for Power Electronics Applications

Recent developmental advances have allowed silicon (Si) semiconductor technology to approach the theoretical limits of the Si material; however, power device requirements for many applications are at a point that the present Si-based power devices cannot handle. The requirements include higher blocking voltages, switching frequencies, efficiency, and reliability. To overcome these limitations, new semiconductor materials for power device applications are needed. For high power requirements, wide-bandgap semiconductors like silicon carbide (SiC), gallium nitride (GaN), and diamond, with their superior electrical properties, are likely candidates to replace Si in the near future. This report compares wide-bandgap semiconductors with respect to their promise and applicability for power applications and predicts the future of power device semiconductor materials.
Date: January 2, 2004
Creator: Ozpineci, B.
Object Type: Report
System: The UNT Digital Library
Coupled processes of fluid flow, solute transport, and geochemical reactions in reactive barriers (open access)

Coupled processes of fluid flow, solute transport, and geochemical reactions in reactive barriers

A complex pattern of coupling between fluid flow and mass transport develops when heterogeneous reactions occur. For instance, dissolution and precipitation reactions can change a porous medium's physical properties, such as pore geometry and thus permeability. These changes influence fluid flow, which in turn impacts the composition of dissolved constituents and the solid phases, and the rate and direction of advective transport. Two-dimensional modeling studies using TOUGHREACT were conducted to investigate the coupling between flow and transport developed as a consequence of differences in density, dissolution precipitation, and medium heterogeneity. The model includes equilibrium reactions for aqueous species, kinetic reactions between the solid phases and aqueous constituents, and full coupling of porosity and permeability changes resulting from precipitation and dissolution reactions in porous media. In addition, a new permeability relationship is implemented in TOUGHREACT to examine the effects of geochemical reactions and density difference on plume migration in porous media. Generally, the evolutions in the concentrations of the aqueous phase are intimately related to the reaction-front dynamics. Plugging of the medium contributed to significant transients in patterns of flow and mass transport.
Date: January 2, 2004
Creator: Kim, Jeongkon; Schwartz, Franklin W.; Xu, Tianfu & Choi, Heechul, and Kim, In S.
Object Type: Article
System: The UNT Digital Library
Discussion of 'Tectonic Controls of Mississippi Valley-type Lead-Zinc Mineralization in Orogenic Forelands' (open access)

Discussion of 'Tectonic Controls of Mississippi Valley-type Lead-Zinc Mineralization in Orogenic Forelands'

None
Date: January 2, 2004
Creator: Kesler, Stephen E.; Chesley, John T.; Christensen, John N.; Hagni, Richard D.; Heijlen, Wouter; Kyle, J. Richard et al.
Object Type: Article
System: The UNT Digital Library
Low-energy operation of the Livermore electron beam ion traps: Atomic spectroscopy of Si V, S VII, and Ar IX (open access)

Low-energy operation of the Livermore electron beam ion traps: Atomic spectroscopy of Si V, S VII, and Ar IX

As part of a project to compile a comprehensive catalog of astrophysically relevant emission lines, we used the low-energy capability of the Lawrence Livermore electron beam ion traps to extend the spectroscopy of neon-like ions and the neighboring charge states to silicon, sulfur, and argon. They present wavelength data of Si V and demonstrate the effect of collisional deexcitation of electric dipole forbidden lines on the 2-3 L-shell spectra of Si V, S VII, and Ar IX.
Date: January 2, 2004
Creator: Lepson, J K & Beiersdorfer, P
Object Type: Article
System: The UNT Digital Library
METAL FILTERS FOR PRESSURIZED FLUID BED COMBUSTION (PFBC) APPLICATIONS (open access)

METAL FILTERS FOR PRESSURIZED FLUID BED COMBUSTION (PFBC) APPLICATIONS

Advanced coal and biomass-based gas turbine power generation technologies (IGCC, PFBC, PCFBC, and Hipps) are currently under development and demonstration. Efforts at the Siemens Westinghouse Power Corporation (SWPC) have been focused on the development and demonstration of hot gas filter systems as an enabling technology for power generation. As part of the demonstration effort, SWPC has been actively involved in the development of advanced filter materials and component configuration, has participated in numerous surveillance programs characterizing the material properties and microstructure of field-tested filter elements, and has undertaken extended, accelerated filter life testing programs. This report reviews SWPC's material and component assessment efforts, identifying the performance, stability, and life of porous commercial metal, advanced alloy, and intermetallic filters under simulated, pressurized fluidized-bed combustion (PFBC) conditions.
Date: January 2, 2004
Creator: Alvin, M. A.
Object Type: Report
System: The UNT Digital Library
MTBE in Gasoline: Clean Air and Drinking Water Issues (open access)

MTBE in Gasoline: Clean Air and Drinking Water Issues

None
Date: January 2, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
MTBE in Gasoline: Clean Air and Drinking Water Issues (open access)

MTBE in Gasoline: Clean Air and Drinking Water Issues

None
Date: January 2, 2004
Creator: McCarthy, James E. & Tiemann, Mary
Object Type: Report
System: The UNT Digital Library
MTBE in Gasoline: Clean Air and Drinking Water Issues (open access)

MTBE in Gasoline: Clean Air and Drinking Water Issues

None
Date: January 2, 2004
Creator: McCarthy, James E. & Tiemann, Mary
Object Type: Report
System: The UNT Digital Library
Rapid thermal cycling of metal-supported solid oxide fuel cellmembranes (open access)

Rapid thermal cycling of metal-supported solid oxide fuel cellmembranes

Solid oxide fuel cell (SOFC) membranes were developed in which zirconia-based electrolyte thin films were supported by a composite metal/ceramic electrode, and were subjected to rapid thermal cycling between 200 and 800 C. The effects of this cycling on membrane performance were evaluated. The membranes, not yet optimized for performance, showed a peak power density of 350mW/cm2at 900 C in laboratory-sized SOFCs that was not affected by the thermal cycling. This resistance to cycling degradation is attributed to the close matching of thermal expansion coefficient of the cermet support electrode with that of the zirconia electrolyte.
Date: January 2, 2004
Creator: Matus, Yuriy B.; De Jonghe, Lutgard C.; Jacobson, Craig P. & Visco, Steven J.
Object Type: Article
System: The UNT Digital Library
A Self-Consistent Approach for Calculating the Effective Hydraulic Conductivity of a Bimodal, Heterogeneous Medium (open access)

A Self-Consistent Approach for Calculating the Effective Hydraulic Conductivity of a Bimodal, Heterogeneous Medium

In this paper, we consider an approach for estimating the effective hydraulic conductivity of a 3D medium with a binary distribution of local hydraulic conductivities. The medium heterogeneity is represented by a combination of matrix medium conductivity with spatially distributed sets of inclusions. Estimation of effective conductivity is based on a self-consistent approach introduced by Shvidler (1985). The tensor of effective hydraulic conductivity is calculated numerically by using a simple system of equations for the main diagonal elements. Verification of the method is done by comparison with theoretical results for special cases and numerical results of Desbarats (1987) and our own numerical modeling. The method was applied to estimating the effective hydraulic conductivity of a 2D and 3D fractured porous medium. The medium heterogeneity is represented by a combination of matrix conductivity and a spatially distributed set of highly conductive fractures. The tensor of effective hydraulic conductivity is calculated for parallel- and random-oriented sets of fractures. The obtained effective conductivity values coincide with Romm's (1966) and Snow's (1969) theories for infinite fracture length. These values are also physically acceptable for the sparsely-fractured-medium case with low fracture spatial density and finite fracture length. Verification of the effective hydraulic conductivity obtained for …
Date: January 2, 2004
Creator: Pozdniakov, Sergey & Tsang, Chin-Fu
Object Type: Article
System: The UNT Digital Library
Sugar Policy Issues (open access)

Sugar Policy Issues

None
Date: January 2, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Supreme Court Recognition of Fifth Amendment Protection for Acts of Production (open access)

Supreme Court Recognition of Fifth Amendment Protection for Acts of Production

None
Date: January 2, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 29, Number 1, Pages 1-248, January 2, 2004 (open access)

Texas Register, Volume 29, Number 1, Pages 1-248, January 2, 2004

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: January 2, 2004
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
U.S. International Trade: Data and Forecasts (open access)

U.S. International Trade: Data and Forecasts

None
Date: January 2, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
USA PATRIOT Act Sunset: Provisions That Expire on December 31, 2005 (open access)

USA PATRIOT Act Sunset: Provisions That Expire on December 31, 2005

None
Date: January 2, 2004
Creator: Doyle, Charles
Object Type: Report
System: The UNT Digital Library
Visualization of microcrack anisotropy in granite affected by afault zone, using confocal laser scanning microscope (open access)

Visualization of microcrack anisotropy in granite affected by afault zone, using confocal laser scanning microscope

Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation.
Date: January 2, 2004
Creator: Onishi, Celia T. & Shimizu, Ichiko
Object Type: Article
System: The UNT Digital Library
Air Quality and Road Emission Results for Fort Stewart, Georgia (open access)

Air Quality and Road Emission Results for Fort Stewart, Georgia

The Directorate of Public Works Environmental & Natural Resources Division (Fort Stewart /Hunter Army Airfield) contracted with the Pacific Northwest National Laboratory (PNNL) to monitor particulate matter (PM) concentrations on Fort Stewart, Georgia. The purpose of this investigation was to establish a PM sampling network using monitoring equipment typically used in U.S. Environmental Protection Agency (EPA) ''saturation sampling'', to determine air quality on the installation. In this initial study, the emphasis was on training-generated PM, not receptor PM loading. The majority of PM samples were 24-hr filter-based samples with sampling frequency ranging from every other day, to once every six days synchronized with the EPA 6th day national sampling schedule. Eight measurement sites were established and used to determine spatial variability in PM concentrations and evaluate whether fluctuations in PM appear to result from training activities and forest management practices on the installation. Data collected to date indicate the average installation PM2.5 concentration is lower than that of nearby urban Savannah, Georgia. At three sites near the installation perimeter, analyses to segregate PM concentrations by direction of air flow across the installation boundary indicate that air (below 80 ft) leaving the installation contains less PM2.5 than that entering the installation. …
Date: February 2, 2004
Creator: Kirkham, Randy R.; Driver, Crystal J.; Chamness, Mickie A. & Barfuss, Brad C.
Object Type: Report
System: The UNT Digital Library
Atmospheric Dispersion Analysis using MACCS2 (open access)

Atmospheric Dispersion Analysis using MACCS2

The Nuclear Regulatory Commission (NRC) Regulatory Guide 1.145 requires an evaluation of the offsite atmospheric dispersion coefficient, {Chi}/Q, as a part of the acceptance criteria in the accident analysis. In it, it requires in sequence computations of (1) the overall site 95th percentile {Chi}/Q, (2) the maximum of the sixteen sector 99.5th percentile {Chi}/Q, and (3) comparison and selection of the worst of the two values for reporting in the safety analysis report (SAR). In all cases, the site-specific meteorology and sector-specific site boundary distances are employed in the evaluation. There are sixteen 22.5-sectors, the nearest site boundary of which is determined within the 45-arc centered on each of the sixteen compass directions.
Date: February 2, 2004
Creator: Glaser, R. & Yang, J. M.
Object Type: Article
System: The UNT Digital Library
Balancing Scientific Publication and National Security Concerns: Issues for Congress (open access)

Balancing Scientific Publication and National Security Concerns: Issues for Congress

There is a lack of consensus regarding the best method of balancing scientific publishing and national security. The current federal policy, as described in National Security Decision Directive 189, is that fundamental research should remain unrestricted and that in the rare case where it is necessary to restrict such information, classification is the appropriate vehicle to do so. Other mechanisms restrict international information flow, where Export Administration Regulations (EAR) and International Traffic in Arms Regulations (ITAR) control export of items and technical information on specific lists. Both EAR and ITAR contain a fundamental research exclusion, but this exclusion is lost if prepublication review of research results for sensitive information occurs.
Date: February 2, 2004
Creator: Shea, Dana A.
Object Type: Report
System: The UNT Digital Library
Clean Air Act: Key Stakeholders' Views on Revisions to the New Source Review Program (open access)

Clean Air Act: Key Stakeholders' Views on Revisions to the New Source Review Program

A letter report issued by the General Accounting Office with an abstract that begins "Environmental Protection Agency (EPA) revisions to the New Source Review (NSR) program to control industrial emissions have drawn attention from state and local agencies that implement the program, as well as industry and environmental and health groups. Under the revisions, companies may not have to install pollution controls when making some facility changes. GAO was asked to obtain the opinions of state air quality officials and other stakeholders on the impact of both the final and proposed revisions EPA issued in December 2002. GAO obtained survey responses from NSR program managers in 44 states and certain localities and contacted six environmental and health groups, and eight industry groups active in the NSR debate. Survey details are available in GAO-04-337SP."
Date: February 2, 2004
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Conceptual Models of Flow through a Heterogeneous, Layered Vadose Zone under a Percolation Pond (open access)

Conceptual Models of Flow through a Heterogeneous, Layered Vadose Zone under a Percolation Pond

Understanding how water and solutes move through the vadose zone is necessary to make effective remedial action decisions where contaminants were spilled or leaked at the ground surface or were buried in shallow land-disposal sites. In layered, heterogeneous systems, high contrasts in hydraulic conductivity can lead to formation of perched water zones, and enhanced lateral spread of contamination. Two conceptual models are considered solute for migration through the vadose zone. In the diffuse flow conceptual model, perched water zones accumulate until the head over the perching layer becomes sufficient to drive the infiltration through the perching layer. In the preferential flow conceptual model, perched water moves laterally until a path around the perching layer is encountered. Preferential flow paths can enhance contaminant migration because greater moisture saturation leads to higher advective velocities, and the preferential flow paths bypass low permeability layers with higher sorption capacity. Monitoring wells and instrumented boreholes were installed around a newly constructed industrial-waste percolation pond and an ephemeral river that lie over a 150-m-thick layered vadose zone. Background data gathered before discharge to the pond began show the presence of at least one, and possibly two, deep perched zones. The shallower zone, at approximately 45-m below …
Date: February 2, 2004
Creator: Baker, Kristine; Hull, Larry; Bennett, Jesse; Ansley, Shannon & Heath, Gail
Object Type: Report
System: The UNT Digital Library