Resource Type

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone (open access)

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

This project seeks to improve the basic understanding of the role of colloids in facilitating the transport of contaminants in the vadose zone. We focus on three major thrusts: (1) thermodynamic stability and mobility of colloids formed by reactions of sediments with highly alkaline tank waste solutions, (2) colloid-contaminant interactions, and (3) in-situ colloid mobilization and colloid facilitated contaminant transport occurring in both contaminated and uncontaminated Hanford sediments.
Date: May 31, 2006
Creator: Flury, Markus; Harsh, James B.; Zachara, John M.; McCarthy, John F. & Lichtner, Peter C.
System: The UNT Digital Library
Commercial Aviation: Costs and Major Factors Influencing Infrastructure Changes at U.S. Airports to Accomodate the New A380 Aircraft (open access)

Commercial Aviation: Costs and Major Factors Influencing Infrastructure Changes at U.S. Airports to Accomodate the New A380 Aircraft

A letter report issued by the Government Accountability Office with an abstract that begins "Airbus S.A.S (Airbus), a European aircraft manufacturer, introduced a new aircraft, the A380 that will be the largest passenger aircraft in the world with expected delivery to its first customers in late 2006. The A380 has a double deck and is expected to seat between 555 and 853 passengers. The A380 is much larger than its competitors with a wingspan of 262 feet, a tail fin about 80 feet high, and a maximum takeoff weight of over 1.2 million pounds. A freight version of the A380 is scheduled for delivery in 2008. Because of the size of the A380, U.S. airports have to make changes to accommodate the aircraft. This may include widening runways and taxiways, or restructuring gate areas to accommodate the additional passengers. This report examines (1) the costs and nature of the changes U.S. airports are making to their infrastructure to accommodate the A380, (2) the funding sources being used to finance these changes, and (3) the major factors influencing the changes being made. The Federal Aviation Administration (FAA) and Airbus provided technical comments on the report. Airbus also commented on the 18 …
Date: May 19, 2006
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Commercialization of a 2.5kW Utility Interactive Inverter for Distributed Generation (open access)

Commercialization of a 2.5kW Utility Interactive Inverter for Distributed Generation

Through this project, Advanced Energy Conversion (AEC) has developed, tested, refined and is preparing to commercialize a 2.5kW utility-interactive inverter system for distributed generation. The inverter technology embodies zero-voltage switching technology that will ultimately yield a system that is smaller, less expensive and more efficient than existing commercial technologies. This program has focused on commercial success through careful synthesis of technology, market-focus and business development. AEC was the primary participant. AEC is utilizing contract manufacturers in the early stages of production, allowing its technical staff to focus on quality control issues and product enhancements. The objective of this project was to bring the AEC inverter technology from its current pre-production state to a commercial product. Federal funds have been used to build and test production-intent inverters, support the implementation of the commercialization plan and bring the product to the point of UL certification.
Date: May 26, 2006
Creator: Torrey, David A.
System: The UNT Digital Library
The Committee on Foreign Investment in the United States (CFIUS) (open access)

The Committee on Foreign Investment in the United States (CFIUS)

The Committee on Foreign Investment in the United States (CFIUS) is an interagency committee that serves the President in overseeing the national security implications of foreign investment in the economy. Since it was established by an Executive Order of President Ford in 1975, the committee has operated in relative obscurity.1 According to a Treasury Department memorandum, the Committee originally was established in order to placate Congress, which had grown concerned over the rapid increase in Organization of the Petroleum Exporting Countries (OPEC) investments in American portfolio assets (Treasury securities, corporate stocks and bonds), and to respond to concerns of some that much of the OPEC investments were being driven by political, rather than by economic, motives.
Date: May 17, 2006
Creator: Jackson, James K.
System: The UNT Digital Library
Compact Fluorescent Lighting in America: Lessons Learned on the Way to Market (open access)

Compact Fluorescent Lighting in America: Lessons Learned on the Way to Market

This report describes the history of compact fluorescent lamps (CFLs) in America. CFLs were introduced in the 1970s; however, it has taken more than 20 years for them to gain widespread recognition in the U.S. residential lighting market. This report reviews the development of CFLs, efforts to increase market acceptance of them, and barriers to that acceptance. Lessons to be learned from this study of CFLs are identified in hopes of assisting future market introduction efforts for other promising energy-efficient technologies. This report was prepared by the Pacific Northwest National Laboratory for the U.S. Department of Energy’s Office of Building Technologies, Emerging Technologies Program.
Date: May 22, 2006
Creator: Sandahl, Linda J.; Gilbride, Theresa L.; Ledbetter, Marc R.; Steward, Heidi E. & Calwell, Chris
System: The UNT Digital Library
Comparative Simulation Syudy of Coupled THM Processes near Back-Filled and Open-Drift Nuclear Waste Repositories in Task D of International DECOVALEX Project (open access)

Comparative Simulation Syudy of Coupled THM Processes near Back-Filled and Open-Drift Nuclear Waste Repositories in Task D of International DECOVALEX Project

As part of the ongoing international DECOVALEX project, four research teams used five different models to simulate coupled thermal, hydrological, and mechanical (THM) processes near underground waste emplacement drifts. The simulations were conducted for two generic repository types, one with open and the other with back-filled repository drifts, under higher and lower post-closure temperature, respectively. In the completed first model inception phase of the project, a good agreement was achieved between the research teams in calculating THM responses for both repository types, although some disagreement in hydrological responses are currently being resolved. Good agreement in the basic thermal-mechanical responses was also achieved for both repository types, even though some teams used relatively simplified thermal-elastic heat-conduction models that neglect complex near-field thermal-hydrological processes. The good agreement between the complex and simplified process models indicates that the basic thermal-mechanical responses can be predicted with a relatively high confidence level.
Date: May 8, 2006
Creator: Rutqvist, J.; Birkholzer, J. T.; Chijimatsu, M.; Kolditz, O.; Liu, Quan-Sheng; Oda, Y. et al.
System: The UNT Digital Library
Comparing Statewide Economic Impacts of New Generation from Wind, Coal, and Natural Gas in Arizona, Colorado, and Michigan (open access)

Comparing Statewide Economic Impacts of New Generation from Wind, Coal, and Natural Gas in Arizona, Colorado, and Michigan

With increasing concerns about energy independence, job outsourcing, and risks of global climate change, it is important for policy makers to understand all impacts from their decisions about energy resources. This paper assesses one aspect of the impacts: direct economic effects. The paper compares impacts to states from equivalent new electrical generation from wind, natural gas, and coal. Economic impacts include materials and labor for construction, operations, maintenance, fuel extraction, and fuel transport, as well as project financing, property tax, and landowner revenues. We examine spending on plant construction during construction years, in addition to all other operational expenditures over a 20-year span. Initial results indicate that adding new wind power can be more economically effective than adding new gas or coal power and that a higher percentage of dollars spent on coal and gas will leave the state. For this report, we interviewed industry representatives and energy experts, in addition to consulting government documents, models, and existing literature. The methodology for this research can be adapted to other contexts for determining economic effects of new power generation in other states and regions.
Date: May 1, 2006
Creator: Tegen, S.
System: The UNT Digital Library
Comparison of Ceramic, Metal and Polymer Crevice Formers on the Crevice Corrosopn Behavior of Ni-CR-Mo Alloy C22 (open access)

Comparison of Ceramic, Metal and Polymer Crevice Formers on the Crevice Corrosopn Behavior of Ni-CR-Mo Alloy C22

A necessary condition for crevice corrosion is that a crevice former create a sufficiently tight, restricted geometry on the metal surface to support the development of critical crevice chemistry. Crevice corrosion is affected by the crevice geometry (tightness) and the properties of the crevice former. The objective of this study is to determine the effect of the crevice former material on the evolution of localized corrosion-damage. A standard crevice corrosion test method is modified by (a) the use of ceramic, metal or polymer materials as the crevice former and (b) the variation of size and shape of the crevice. This study focuses on the post initiation stage of crevice corrosion and addresses factors that may limit the initiation of localized corrosion and also slow or stop the continued propagation of corrosion. Controlled crevice corrosion tests are performed under aggressive, accelerated conditions on Ni-Cr-Mo alloy C-22 and other alloys for comparison. Multiple techniques are used to examine the crevice corrosion damage evolution. Current measurements during the test provide a direct measure of the corrosion rate and indicate the initiation and any stifling or arrest. The localized corrosion is found to be stifled or arrested under several test conditions. The corrosion damage …
Date: May 8, 2006
Creator: Shan, X. & Payer, J.H.
System: The UNT Digital Library
Comparison of Marine Microalgae Culture Systems for Fuels Production and Carbon Sequestration (open access)

Comparison of Marine Microalgae Culture Systems for Fuels Production and Carbon Sequestration

The dual problems of global fossil fuels supplies and global warming focus attention on the need to develop technologies that can provide large amounts of renewable fuels without contributing to global warming. The capture of power plant flue gas CO2 using microalgae cultures is one potential technology that could meet this objective. The central R&D issues are the design and operation of low-cost algal mass culture systems and the development of algal strains and cultivation techniques that can achieve very high biomass productivities. The major objective of this project was to develop mass culture techniques that could result in greatly increased biomass productivities, well above the about 50 metric tons per hectare per year (mt/ha/y) currently achievable. In this project, two marine microalgae species, the diatom Cyclotella sp.. and the green alga Tetraselmis sp., were cultivated on seawater in both open ponds and closed photo bioreactors, under a variety of different cultivation conditions. Simultaneous operation of the closed photo bioreactors and open ponds demonstrated similar productivities, under the same operating conditions. Thus the very expensive closed systems do not provide any major or inherent advantages in microalgae production over open ponds. Mutants of Cyclotella sp. were developed that exhibited reduced …
Date: May 30, 2006
Creator: Weissman, Joseph C & Polle, Juergen
System: The UNT Digital Library
A Comparison of the Pay of Top Executives and Other Workers (open access)

A Comparison of the Pay of Top Executives and Other Workers

This report provides an overview of the comparison of the pay of top executives and other workers.
Date: May 4, 2006
Creator: Levine, Linda
System: The UNT Digital Library
Completion Report for Well ER-12-3 Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain (open access)

Completion Report for Well ER-12-3 Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain

Well ER-12-3 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. The well was drilled in March and April 2005 as part of a hydrogeologic investigation program for the Rainier Mesa-Shoshone Mountain Corrective Action Unit. The overall purpose of the well was to gather subsurface data to better characterize the hydrogeology of central Rainier Mesa, especially in the older Tertiary volcanic rocks and Paleozoic sedimentary rocks. The main 47.0-centimeter hole was drilled to a depth of 799.2 meters and cased with 33.97-centimeter casing to 743.1 meters. The hole diameter was then decreased to 31.1 centimeters, and the well was drilled to a total depth of 1,496.0 meters. The completion string consisted of 13.97-centimeter stainless steel casing, with two slotted intervals open to the lower carbonate aquifer, suspended from 19.37-centimeter carbon steel casing. A piezometer string was installed outside the 33.97-centimeter casing to a depth of 467.1 meters to monitor a zone of perched water within the Tertiary volcanic section. Data gathered during and shortly after hole construction include composite drill cuttings samples collected every 3 meters (extra cuttings …
Date: May 1, 2006
Creator: United States. National Nuclear Security Administration. Nevada Site Office.
System: The UNT Digital Library
Completion Report for Well ER-12-4, Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain (includes Errata Sheet) (open access)

Completion Report for Well ER-12-4, Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain (includes Errata Sheet)

Well ER-12-4 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. This well was drilled in May 2005, as part of a hydrogeologic investigation program for the Rainier Mesa-Shoshone Mountain Corrective Action Unit in the north-central portion of the Nevada Test Site. The well is located on Rainier/Aqueduct Mesa, northwest of Yucca Flat, within Area 12 of the Nevada Test Site. The well provided information regarding the radiological and physical environment near underground nuclear tests conducted in U12t Tunnel, information on the pre-Tertiary rocks in the area, and depth to the regional water table.
Date: May 1, 2006
Creator: United States. National Nuclear Security Administration. Nevada Site Office.
System: The UNT Digital Library
Computer Calculations of Eddy-Current Power Loss in Rotating Titanium Wheels and Rims in Localized Axial Magnetic Fields (open access)

Computer Calculations of Eddy-Current Power Loss in Rotating Titanium Wheels and Rims in Localized Axial Magnetic Fields

We have performed preliminary computer-based, transient, magnetostatic calculations of the eddy-current power loss in rotating titanium-alloy and aluminum wheels and wheel rims in the predominantly axially-directed, steady magnetic fields of two small, solenoidal coils. These calculations have been undertaken to assess the eddy-current power loss in various possible International Linear Collider (ILC) positron target wheels. They have also been done to validate the simulation code module against known results published in the literature. The commercially available software package used in these calculations is the Maxwell 3D, Version 10, Transient Module from the Ansoft Corporation.
Date: May 15, 2006
Creator: Mayhall, D. J.; Stein, W. & Gronberg, J. B.
System: The UNT Digital Library
The Concentration of Household Wealth (open access)

The Concentration of Household Wealth

This report examines the data of the survey on the distribution of household wealth.
Date: May 23, 2006
Creator: Cashell, Brian W.
System: The UNT Digital Library
Concentrations of Radionuclides and Trace Elements in Environmantal Media arond te Dual-Axis Radiographic Hydrodynamic Test Facilit at Los Alamos National Laboratory during 2005 (open access)

Concentrations of Radionuclides and Trace Elements in Environmantal Media arond te Dual-Axis Radiographic Hydrodynamic Test Facilit at Los Alamos National Laboratory during 2005

The Mitigation Action Plan (MAP) for the Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory requires that samples of biotic and abiotic media be collected after operations began to determine if there are any human health or environmental impacts. The DARHT facility is the Laboratory's principal explosive test facility. To this end, samples of soil and sediment, vegetation, bees, and birds were collected around the facility in 2005 and analyzed for concentrations of {sup 3}H, {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 234}U, {sup 235}U, {sup 238}U, Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, and Tl. Bird populations have also been monitored. Contaminant results, which represent up to six sample years since the start of operations, were compared with (1) baseline statistical reference levels (BSRLs) established over a four-year preoperational period before DARHT facility operations, (2) screening levels (SLs), and (3) regulatory standards. Most radionuclides and trace elements were below BSRLs and those few samples that contained radionuclides and trace elements above BSRLs were below SLs. Concentrations of radionuclides and nonradionuclides in biotic and abiotic media around the DARHT facility do not pose a significant human health hazard. …
Date: May 15, 2006
Creator: Gonzales, G. J.; Fresquez, P.R.; C.D.Hathcock & Keller, D.C.
System: The UNT Digital Library
Concurrent Single-Executable CCSM with MPH Library (open access)

Concurrent Single-Executable CCSM with MPH Library

Community Climate System Model (CCSM) is currently a multi-executable system based on the Multi-Program Multi-Data (MPMD) mechanism. Each component is compiled into a separate executable. MPMD is normally cumbersome in usage and vendor support is sometimes limited or completely unavailable, such as on BlueGene/L. Also smaller groups and institutions would like to run CCSM locally, rather than relying on large computer centers. So, single-executable CCSM is under request. We are developing a multi-executable and single-executable coexisting version of CCSM. In single-executable, each component is organized as a subroutine, which is called from a master program. Different components run simultaneously. This is accomplished by redesigning the top level CCSM structures using the Multi-Program Handshaking (MPH) library.
Date: May 15, 2006
Creator: He, Yun & Ding, Chris H.Q.
System: The UNT Digital Library
Congressional Gifts and Travel: Proposals for the 109th Congress (open access)

Congressional Gifts and Travel: Proposals for the 109th Congress

This report provides a brief analysis of the proposal for change introduced or discussed in the 109th Congress and will be updated as events warrant.
Date: May 12, 2006
Creator: Amer, Mildred
System: The UNT Digital Library
Congressional Liaison Offices of Selected Federal Agencies (open access)

Congressional Liaison Offices of Selected Federal Agencies

This report provides information about the Congressional Liaison Offices of Selected Federal Agencies. This list of about 150 congressional Liaison is intended to help congressional offices in placing telephone calls and addressing correspondence to government agencies.
Date: May 23, 2006
Creator: Watkins, Zina L. & Berry, Carla
System: The UNT Digital Library
Contact Interface Verification for DYNA3D Scenario 1: Basic Contact (open access)

Contact Interface Verification for DYNA3D Scenario 1: Basic Contact

A suite of test problems has been developed to examine contact behavior within the nonlinear, three-dimensional, explicit finite element analysis (FEA) code DYNA3D (Lin, 2005). The test problems address the basic functionality of the contact algorithms, including the behavior of various kinematic, penalty, and Lagrangian enforcement formulations. The results from the DYNA3D analyses are compared to closed form solutions to verify the contact behavior. This work was performed as part of the Verification and Validation efforts of LLNL W Program within the NNSA's Advanced Simulation and Computing (ASC) Program. DYNA3D models the transient dynamic response of solids and structures including the interactions between disjoint bodies (parts). A wide variety of contact surfaces are available to represent the diverse interactions possible during an analysis, including relative motion (sliding), separation and gap closure (voids), and fixed relative position (tied). The problem geometry may be defined using a combination of element formulations, including one-dimensional beam and truss elements, two-dimensional shell elements, and three-dimensional solid elements. Consequently, it is necessary to consider various element interactions for each contact algorithm being verified. Most of the contact algorithms currently available in DYNA3D are examined; the exceptions are the Type 4--Single Surface Contact and Type 11--SAND algorithms. …
Date: May 10, 2006
Creator: McMichael, L D
System: The UNT Digital Library
Contact Interface Verification for DYNA3D Scenario 2: Multi-Surface Contact (open access)

Contact Interface Verification for DYNA3D Scenario 2: Multi-Surface Contact

A suite of test problems has been developed to examine contact behavior within the nonlinear, three-dimensional, explicit finite element analysis (FEA) code DYNA3D (Lin, 2005). The test problems use multiple interfaces and a combination of enforcement methods to assess the basic functionality of the contact algorithms. The results from the DYNA3D analyses are compared to closed form solutions to verify the contact behavior. This work was performed as part of the Verification and Validation efforts of LLNL W Program within the NNSA's Advanced Simulation and Computing (ASC) Program. DYNA3D models the transient dynamic response of solids and structures including the interactions between disjoint bodies (parts). A wide variety of contact surfaces are available to represent the diverse interactions possible during an analysis, including relative motion (sliding), separation and gap closure (voids), and fixed relative position (tied). The problem geometry may be defined using a combination of element formulations, including one-dimensional beam and truss elements, two-dimensional shell elements, and three-dimensional solid elements. Consequently, it is necessary to consider various element interactions during contact. This report and associated test problems examine the scenario where multiple bodies interact with each other via multiple interfaces. The test problems focus on whether any ordering issues …
Date: May 10, 2006
Creator: McMichael, L D
System: The UNT Digital Library
Continuity of Operations: Selected Agencies Could Improve Planning for Use of Alternate Facilities and Telework during Disruptions (open access)

Continuity of Operations: Selected Agencies Could Improve Planning for Use of Alternate Facilities and Telework during Disruptions

A letter report issued by the Government Accountability Office with an abstract that begins "To ensure that essential government services are available in emergencies, federal agencies are required to develop continuity of operations (COOP) plans. The Federal Emergency Management Agency (FEMA), within the Department of Homeland Security (DHS), is responsible for overseeing and assessing the status of COOP capabilities of federal executive branch agencies. It has developed guidance stating that agency COOP plans must designate alternate facilities and prepare personnel for unannounced relocation to these facilities. The guidance also states that agencies should consider the use of telework in their continuity plans. GAO was asked to follow up on its previous work on COOP planning and determine, among other things, to what extent (1) 6 selected agencies prepared their alternate facilities and (2) 23 major agencies made preparations necessary to effectively use telework in emergency situations."
Date: May 11, 2006
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Control Systems Cyber Security:Defense in Depth Strategies (open access)

Control Systems Cyber Security:Defense in Depth Strategies

Information infrastructures across many public and private domains share several common attributes regarding IT deployments and data communications. This is particularly true in the control systems domain. A majority of the systems use robust architectures to enhance business and reduce costs by increasing the integration of external, business, and control system networks. However, multi-network integration strategies often lead to vulnerabilities that greatly reduce the security of an organization, and can expose mission-critical control systems to cyber threats. This document provides guidance and direction for developing ‘defense-in-depth’ strategies for organizations that use control system networks while maintaining a multi-tier information architecture that requires: Maintenance of various field devices, telemetry collection, and/or industrial-level process systems Access to facilities via remote data link or modem Public facing services for customer or corporate operations A robust business environment that requires connections among the control system domain, the external Internet, and other peer organizations.
Date: May 1, 2006
Creator: Kuipers, David & Fabro, Mark
System: The UNT Digital Library
Conversion of NIMROD simulation results for graphical analysis using VisIt (open access)

Conversion of NIMROD simulation results for graphical analysis using VisIt

Software routines developed to prepare NIMROD [C. R. Sovinec et al., J. Comp. Phys. 195, 355 (2004)] results for three-dimensional visualization from simulations of the Sustained Spheromak Physics Experiment (SSPX ) [E. B. Hooper et al., Nucl. Fusion 39, 863 (1999)] are presented here. The visualization is done by first converting the NIMROD output to a format known as legacy VTK and then loading it to VisIt, a graphical analysis tool that includes three-dimensional rendering and various mathematical operations for large data sets. Sample images obtained from the processing of NIMROD data with VisIt are included.
Date: May 3, 2006
Creator: Romero-Talamas, C. A.
System: The UNT Digital Library
Cooperative R&D: Federal Efforts to Promote Industrial Competitiveness (open access)

Cooperative R&D: Federal Efforts to Promote Industrial Competitiveness

In response to the foreign challenge in the global marketplace, the United States Congress has explored ways to stimulate technological advancement in the private sector. The government has supported various efforts to promote cooperative research and development activities among industry, universities, and the federal R&D establishment. Among the issues before Congress are whether joint ventures contribute to industrial competitiveness and what role, if any, the government has in facilitating such agreements. Collaborative ventures are intended to accommodate the strengths and responsibilities of all sectors involved innovation and technology development. Given the increased popularity of cooperative programs, questions might be raised as to whether they are meeting expectations. These include questions about the emphasis on collaborative ventures in research rather than in technology development; cooperative manufacturing; defense vs. civilian support; and access by foreign companies.
Date: May 30, 2006
Creator: Schacht, Wendy H.
System: The UNT Digital Library