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Transmission Lines: Issues Associated with High-Voltage Direct-Current Transmission Lines along Transportation Rights of Way (open access)

Transmission Lines: Issues Associated with High-Voltage Direct-Current Transmission Lines along Transportation Rights of Way

Correspondence issued by the Government Accountability Office with an abstract that begins "Electricity is central to the national economy and the daily lives of many Americans, powering homes, businesses, and industries. Today, an extensive system consisting of more than 150,000 miles of high-voltage transmission lines works to provide reliable electricity service and transport electricity from power plants to consumers. Federal and state entities share responsibility for regulating the electricity system. On the federal level, the Federal Energy Regulatory Commission (FERC) regulates interstate transmission of electricity and wholesale rates, among other regulatory activities. State public utility commissions are generally responsible for regulating retail electricity sales and, in some cases, planning for new power plants and transmission lines. However, as studies have shown, growth in electricity demand has strained the nation's transmission system, resulting in less flexibility to respond to system problems and an increased risk of potential blackouts. These issues have led some to suggest that new lines or other investments in the transmission system may be required to increase capacity and accommodate growing electricity demand. Several companies have recently introduced proposals to build new high-voltage direct-current (HVDC) transmission lines. Some of these proposed lines would follow active transportation rights of …
Date: February 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Best Practices: Increased Focus on Requirements and Oversight Needed to Improve DOD's Acquisition Environment and Weapon System Quality (open access)

Best Practices: Increased Focus on Requirements and Oversight Needed to Improve DOD's Acquisition Environment and Weapon System Quality

A letter report issued by the Government Accountability Office with an abstract that begins "A Senate report related to the National Defense Authorization Act for Fiscal Year 2007 asked GAO to compare quality management practices used by the Department of Defense (DOD) and its contractors to those used by leading commercial companies and make suggestions for improvement. To do this, GAO (1) determined the impact of quality problems on selected weapon systems and prime contractor practices that contributed to the problems; (2) identified commercial practices that can be used to improve DOD weapon systems; (3) identified problems that DOD must overcome; and (4) identified recent DOD initiatives that could improve quality. GAO examined 11 DOD weapon systems with known quality problems and met with quality officials from DOD, defense prime contractors, and five leading commercial companies that produce complex products and/or are recognized for quality products."
Date: February 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Military Readiness: Navy Is Making Progress Implementing Its Fleet Response Plan, but Has Not Fully Developed Goals, Measures, and Resource Needs (open access)

Military Readiness: Navy Is Making Progress Implementing Its Fleet Response Plan, but Has Not Fully Developed Goals, Measures, and Resource Needs

A letter report issued by the Government Accountability Office with an abstract that begins "The Navy initiated its Fleet Response Plan (FRP) in March 2003 as a critical enabler to help meet the new demands of the twenty-first century security environment. FRP represents a major change in the way the Navy manages its forces, and is intended to more rapidly prepare and then sustain readiness in ships and squadrons. To achieve the desired capabilities under FRP, the Navy has altered its training, maintenance, and manning practices. The Navy expects this new readiness approach will enable its forces to provide presence and engagement in forward areas, as well as surge a greater number of ships on short notice. The Navy intends to achieve this goal without increasing its operations and maintenance budget of about $40 billion for each of the next 5 years. However, GAO previously reported that the Navy had not fully incorporated a sound management approach to guide and assess implementation of FRP. As a result, GAO was asked to examine the extent to which the Navy has (1) made progress in implementing a sound management approach for FRP and (2) evaluated the long-term risks and tradeoffs of FRP-related …
Date: February 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Studying neutrino oscillations using quasi-elastic events in MINOS (open access)

Studying neutrino oscillations using quasi-elastic events in MINOS

MINOS (Main Injector Neutrino Oscillation Search), is a long baseline neutrino experiment designed to search for neutrino oscillations using two detectors at Fermi National Accelerator Laboratory, IL (Near Detector) and Soudan, MN (Far Detector). It will study {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations and make a measurement on the oscillation parameters, {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23}, via a {nu}{sub {mu}} beam made at Fermilab. Charge current neutrino interactions in the MINOS detectors are of three types: quasi-elastic scattering (QEL), resonance scattering (RES) and deep inelastic scattering (DIS). Of these, quasi-elastic scattering leaves the cleanest signal with just one {mu} and one proton in the final state, thus rendering the reconstruction of the neutrino energy more accurate. This thesis will outline a method to separate QEL events from the others in the two detectors and perform a calculation of {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} using those events. The period under consideration was May 2005 to February 2006. The number of observed quasi-elastic events with energies below 10 GeV was 29, where the expected number was 60 {+-} 3. A fit to the energy distribution of these events gives {Delta}m{sub 23}{sup 2} = 2.91{sub -0.53}{sup +0.49}(stat){sub …
Date: February 1, 2008
Creator: Kumaratunga, Sujeewa Terasita
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Innovations in Wind and Solar PV Financing (open access)

Innovations in Wind and Solar PV Financing

There is growing national interest in renewable energy development based on the economic, environmental, and security benefits that these resources provide. Historically, greater development of our domestic renewable energy resources has faced a number of hurdles, primarily related to cost, regulation, and financing. With the recent sustained increase in the costs and associated volatility of fossil fuels, the economics of renewable energy technologies have become increasingly attractive to investors, both large and small. As a result, new entrants are investing in renewable energy and new business models are emerging. This study surveys some of the current issues related to wind and solar photovoltaic (PV) energy project financing in the electric power industry, and identifies both barriers to and opportunities for increased investment.
Date: February 1, 2008
Creator: Cory, K.; Coughlin, J.; Jenkin, T.; Pater, J. & Swezey, B.
Object Type: Report
System: The UNT Digital Library
Aquatic Species Program (ASP): Lessons Learned (open access)

Aquatic Species Program (ASP): Lessons Learned

Presentation on lessons learned from the U.S. Department of Energy?s Aquatic Species Program 1978-1996 microalgae R&D activities, presented at the 2008 AFOSR Workshop in Washington, D.C.
Date: February 1, 2008
Creator: Jarvis, E. E.
Object Type: Article
System: The UNT Digital Library
Generalization of the ERIT Principle and Method (open access)

Generalization of the ERIT Principle and Method

The paper describes the generalization of the method to produce secondary particles with a low-energy and low-intensity primary beam circulating in a Storage Ring with the Emittance-Recovery by Internal-Target (ERIT).
Date: February 1, 2008
Creator: Ruggiero, A.
Object Type: Report
System: The UNT Digital Library
Stay Rates of Foreign Doctorate Recipients from U.S. Universities, 2005 (open access)

Stay Rates of Foreign Doctorate Recipients from U.S. Universities, 2005

This is the latest in a series of studies conducted for the National Science Foundation to estimate the proportion of foreign science / engineering doctorate recipients from U.S. universities who stayed in the United States after graduation. Sixty-six percent of those who graduated in 2003 were still in the United States in 2005, a 5 percent decline since the last report. But the five-year stay rate continues to climb, now at 68 percent.
Date: February 1, 2008
Creator: Finn, Mike
Object Type: Report
System: The UNT Digital Library
Heating, Ventilating, and Air-Conditioning: Recent Advances in Diagnostics and Controls to Improve Air-Handling System Performance (open access)

Heating, Ventilating, and Air-Conditioning: Recent Advances in Diagnostics and Controls to Improve Air-Handling System Performance

The performance of air-handling systems in buildings needs to be improved. Many of the deficiencies result from myths and lore and a lack of understanding about the non-linear physical principles embedded in the associated technologies. By incorporating these principles, a few important efforts related to diagnostics and controls have already begun to solve some of the problems. This paper illustrates three novel solutions: one rapidly assesses duct leakage, the second configures ad hoc duct-static-pressure reset strategies, and the third identifies useful intermittent ventilation strategies. By highlighting these efforts, this paper seeks to stimulate new research and technology developments that could further improve air-handling systems.
Date: February 1, 2008
Creator: Wray, Craig; Wray, Craig P.; Sherman, Max H.; Walker, I. S.; Dickerhoff, D. J. & Federspiel, C. C.
Object Type: Article
System: The UNT Digital Library
One-Axis Trackers -- Improved Reliability, Durability, Performance, and Cost Reduction; Final Subcontract Technical Status Report, 2 May 2006 - 31 August 2007 (open access)

One-Axis Trackers -- Improved Reliability, Durability, Performance, and Cost Reduction; Final Subcontract Technical Status Report, 2 May 2006 - 31 August 2007

The overall objective of this subcontract is to reduce the total cost of electricity generated by single-axis tracking solar energy systems for utility and other large-scale commercial applications by improving performance and reliability and by reducing installation time, cost, and environmental impact.
Date: February 1, 2008
Creator: Shingleton, J.
Object Type: Report
System: The UNT Digital Library
Sandia National Laboratories Advanced Simulation and Computing (ASC) : appraisal method for the implementation of the ASC software quality engineering practices: Version 1.0. (open access)

Sandia National Laboratories Advanced Simulation and Computing (ASC) : appraisal method for the implementation of the ASC software quality engineering practices: Version 1.0.

This document provides a guide to the process of conducting software appraisals under the Sandia National Laboratories (SNL) ASC Program. The goal of this document is to describe a common methodology for planning, conducting, and reporting results of software appraisals thereby enabling: development of an objective baseline on implementation of the software quality engineering (SQE) practices identified in the ASC Software Quality Plan across the ASC Program; feedback from project teams on SQE opportunities for improvement; identification of strengths and opportunities for improvement for individual project teams; guidance to the ASC Program on the focus of future SQE activities Document contents include process descriptions, templates to promote consistent conduct of appraisals, and an explanation of the relationship of this procedure to the SNL ASC software program.
Date: February 1, 2008
Creator: Turgeon, Jennifer & Minana, Molly A.
Object Type: Report
System: The UNT Digital Library
Drug Test Information for HRP-Certified Individuals and HRP Candidates (open access)

Drug Test Information for HRP-Certified Individuals and HRP Candidates

Overview of the Department of Energy's Human Reliability Program drug testing requirements.
Date: February 1, 2008
Creator: Center for Human Reliability Studies
Object Type: Report
System: The UNT Digital Library
Cygnus Diverter Switch Analysis (open access)

Cygnus Diverter Switch Analysis

The Cygnus Dual Beam Radiographic Facility consists of two 2.25-MV, 60-kA, 50-ns x-ray sources fielded in an underground laboratory at the Nevada Test Site. The tests performed in this laboratory involve study of the dynamic properties of plutonium and are called subcritical experiments. From end-to-end, the Cygnus machines utilize the following components: Marx generator, water-filled pulse-forming line (PFL), waterfilled coaxial transmission line (WTL), 3-cell inductive voltage adder (IVA), and rod-pinch diode. The upstream WTL interface to the PFL is via a radial insulator with coaxial geometry. The downstream WTL terminates in a manifold where the center conductor splits into three lines which individually connect to each of the IVA cell inputs. There is an impedance mismatch at this juncture. It is a concern that a reflected pulse due to anomalous behavior in the IVA or diode might initiate breakdown upon arrival at the upstream PFL/WTL insulator. Therefore near the beginning of the WTL a radial diverter switch is installed to protect the insulator from over voltage and breakdown. The diverter has adjustable gap spacing, and an in-line aqueous-solution (sodium thiosulfate) resistor array for energy dissipation. There are capacitive voltage probes at both ends of the WTL and on the diverter …
Date: February 1, 2008
Creator: G. Corrow, M. Hansen, D. Henderson, C. Mitton et al.
Object Type: Article
System: The UNT Digital Library
Automated Manufacturing of High Efficiency Modules: Final Subcontract Technical Status Report, 21 March 2005 - 31 August 2007 (open access)

Automated Manufacturing of High Efficiency Modules: Final Subcontract Technical Status Report, 21 March 2005 - 31 August 2007

SunPower Corp. describes its research to develop low-cost, next-generation SunPower modules with 30-year warranties and at least 50% higher energy production per area relative to today's typical multicrystalline Si modules.
Date: February 1, 2008
Creator: Rose, D.; Jester, T. & Bunea, G.
Object Type: Report
System: The UNT Digital Library
TMIST-2 Transport Test (open access)

TMIST-2 Transport Test

In anticipation of the TMIST-2 experiment in the Advanced Test Reactor, there was a need to determine if the tritium that is expected to be observed at the outlet of the experiment would be seen or if it may be lost on its way from the experiment in the core to the measurement station. To assist in resolving that issue, a bench-scale experiment was conducted in the Idaho National Laboratory’s Safety and Tritium Applied Research (STAR) facility using deuterium and a mass spectrometer in lieu of tritium with ion chambers, bubblers, and scintillation counting. The experiment replicated the concentration of the hydrogen isotope, the flow rates anticipated, and the residence times. It was found that there was initial uptake on tubing walls, presumably due to oxidation of the hydrogen isotopes to water and adsorption or isotopic exchange, but that saturates relatively quickly, and once saturated, the concentration of deuterium at the outlet of the tubing system was essentially the same as it was at the experiment inlet under the conditions modeled in the experiment.
Date: February 1, 2008
Creator: Longhurst, Glen R.
Object Type: Report
System: The UNT Digital Library
Basic Research Needs for Materials Under Extreme Environments. Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007 (open access)

Basic Research Needs for Materials Under Extreme Environments. Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007

To evaluate the potential for developing revolutionary new materials that will meet demanding future energy requirements that expose materials to environmental extremes.
Date: February 1, 2008
Creator: Wadsworth, J.; Crabtree, G. W.; Hemley, R. J.; Falcone, R.; Robertson, I.; Stringer, J. et al.
Object Type: Report
System: The UNT Digital Library
Shell Element Verification & Regression Problems for DYNA3D (open access)

Shell Element Verification & Regression Problems for DYNA3D

A series of quasi-static regression/verification problems were developed for the triangular and quadrilateral shell element formulations contained in Lawrence Livermore National Laboratory's explicit finite element program DYNA3D. Each regression problem imposes both displacement- and force-type boundary conditions to probe the five independent nodal degrees of freedom employed in the targeted formulation. When applicable, the finite element results are compared with small-strain linear-elastic closed-form reference solutions to verify select aspects of the formulations implementation. Although all problems in the suite depict the same geometry, material behavior, and loading conditions, each problem represents a unique combination of shell formulation, stabilization method, and integration rule. Collectively, the thirty-six new regression problems in the test suite cover nine different shell formulations, three hourglass stabilization methods, and three families of through-thickness integration rules.
Date: February 1, 2008
Creator: Zywicz, E
Object Type: Report
System: The UNT Digital Library
Local Impacts of Mercury Emissions from the Three Pennsylvania Coal Fired Power Plants. (open access)

Local Impacts of Mercury Emissions from the Three Pennsylvania Coal Fired Power Plants.

The Clean Air Interstate Rule (CAIR) and the Clean Air Mercury Rule (CAMR) as proposed by the U.S. Environmental Protection Agency (EPA) when fully implemented will lead to reduction in mercury emissions from coal-fired power plants by 70 percent to fifteen tons per year by 2018. The EPA estimates that mercury deposition would be reduced 8 percent on average in the Eastern United States. The CAMR permits cap-and-trade approach that requires the nationwide emissions to meet the prescribed level, but do not require controls on each individual power plant. This has led to concerns that there may be hot-spots of mercury contamination near power plants. Partially because of this concern, many states including Pennsylvania have implemented, or are considering, state regulations that are stricter on mercury emissions than those in the CAMR. This study examined the possibility that coal-fired power plants act as local sources leading to mercury 'hot spots'. Soil and oak leaf samples from around three large U.S. coal-fired power plants in Western Pennsylvania were collected and analyzed for evidence of 'hot spots'. These three plants (Conemaugh, Homer City, and Keystone) are separated by a total distance of approximately 30 miles. Each emits over 500 pounds of mercury …
Date: February 1, 2008
Creator: Sullivan, T.; Adams, J.; Bender, M.; Bu, C.; Piccolo, N. & Campbell, C.
Object Type: Report
System: The UNT Digital Library
A measurement of the neutral current neutrino-nucleon elastic cross section at MiniBooNE (open access)

A measurement of the neutral current neutrino-nucleon elastic cross section at MiniBooNE

The neutral current neutrino-nucleon elastic interaction {nu} N {yields} {nu} N is a fundamental process of the weak interaction ideally suited for characterizing the structure of the nucleon neutral weak current. This process comprises {approx}18% of neutrino events in the neutrino oscillation experiment, MiniBooNE, ranking it as the experiment's third largest process. Using {approx}10% of MiniBooNE's available neutrino data, a sample of these events were identified and analyzed to determine the differential cross section as a function of the momentum transfer of the interaction, Q{sup 2}. This is the first measurement of a differential cross section with MiniBooNE data. From this analysis, a value for the nucleon axial mass M{sub A} was extracted to be 1.34 {+-} 0.25 GeV consistent with previous measurements. The integrated cross section for the Q{sup 2} range 0.189 {yields} 1.13 GeV{sup 2} was calculated to be (8.8 {+-} 0.6(stat) {+-} 0.2(syst)) x 10{sup -40} cm{sup 2}.
Date: February 1, 2008
Creator: Cox, David Christopher
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Innovative solar thermochemical water splitting. (open access)

Innovative solar thermochemical water splitting.

Sandia National Laboratories (SNL) is evaluating the potential of an innovative approach for splitting water into hydrogen and oxygen using two-step thermochemical cycles. Thermochemical cycles are heat engines that utilize high-temperature heat to produce chemical work. Like their mechanical work-producing counterparts, their efficiency depends on operating temperature and on the irreversibility of their internal processes. With this in mind, we have invented innovative design concepts for two-step solar-driven thermochemical heat engines based on iron oxide and iron oxide mixed with other metal oxides (ferrites). The design concepts utilize two sets of moving beds of ferrite reactant material in close proximity and moving in opposite directions to overcome a major impediment to achieving high efficiency--thermal recuperation between solids in efficient counter-current arrangements. They also provide inherent separation of the product hydrogen and oxygen and are an excellent match with high-concentration solar flux. However, they also impose unique requirements on the ferrite reactants and materials of construction as well as an understanding of the chemical and cycle thermodynamics. In this report the Counter-Rotating-Ring Receiver/Reactor/Recuperator (CR5) solar thermochemical heat engine and its basic operating principals are described. Preliminary thermal efficiency estimates are presented and discussed. Our ferrite reactant material development activities, thermodynamic studies, …
Date: February 1, 2008
Creator: Hogan, Roy E. Jr.; Siegel, Nathan P.; Evans, Lindsey R.; Moss, Timothy A.; Stuecker, John Nicholas (Robocasting Enterprises, Albuquerque, NM); Diver, Richard B., Jr. et al.
Object Type: Report
System: The UNT Digital Library
Neutronic Assessment of Transmutation Target Compositions in Heterogeneous Sodium Fast Reactor Geometries (open access)

Neutronic Assessment of Transmutation Target Compositions in Heterogeneous Sodium Fast Reactor Geometries

The sodium fast reactor is under consideration for consuming the transuranic waste in the spent nuclear fuel generated by light water reactors. This work is concerned with specialized target assemblies for an oxide-fueled sodium fast reactor that are designed exclusively for burning the americium and higher mass actinide component of light water reactor spent nuclear fuel (SNF). The associated gamma and neutron radioactivity, as well as thermal heat, associated with decay of these actinides may significantly complicate fuel handling and fabrication of recycled fast reactor fuel. The objective of using targets is to isolate in a smaller number of assemblies these concentrations of higher actinides, thus reducing the volume of fuel having more rigorous handling requirements or a more complicated fabrication process. This is in contrast to homogeneous recycle where all recycled actinides are distributed among all fuel assemblies. Several heterogeneous core geometries were evaluated to determine the fewest target assemblies required to burn these actinides without violating a set of established fuel performance criteria. The DIF3D/REBUS code from Argonne National Laboratory was used to perform the core physics and accompanying fuel cycle calculations in support of this work. Using the REBUS code, each core design was evaluated at the …
Date: February 1, 2008
Creator: Bays, Samuel E.; Ferrer, Rodolfo M.; Pope, Michael A.; Forget, Benoit & Asgari, Mehdi
Object Type: Report
System: The UNT Digital Library
Status of Overseas Microgrid Programs: Microgrid Research Activities in the U.S. (open access)

Status of Overseas Microgrid Programs: Microgrid Research Activities in the U.S.

None
Date: February 1, 2008
Creator: Marnay, Chris; Marnay, Chris & Zhou, Nan
Object Type: Article
System: The UNT Digital Library
Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton + Jets Events with the Collider Detector at Fermilab (open access)

Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton + Jets Events with the Collider Detector at Fermilab

We have measured the top quark mass with the dynamical likelihood method. The data corresponding to an integrated luminosity of 1.7fb{sup -1} was collected in proton antiproton collisions at a center of mass energy of 1.96 TeV with the CDF detector at Fermilab Tevatron during the period March 2002-March 2007. We select t{bar t} pair production candidates by requiring one high energy lepton and four jets, in which at least one of jets must be tagged as a b-jet. In order to reconstruct the top quark mass, we use the dynamical likelihood method based on maximum likelihood method where a likelihood is defined as the differential cross section multiplied by the transfer function from observed quantities to parton quantities, as a function of the top quark mass and the jet energy scale(JES). With this method, we measure the top quark mass to be 171.6 {+-} 2.0 (stat.+ JES) {+-} 1.3(syst.) = 171.6 {+-} 2.4 GeV/c{sup 2}.
Date: February 1, 2008
Creator: Kubo, Taichi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Tape casting of magnesium oxide. (open access)

Tape casting of magnesium oxide.

A tape casting procedure for fabricating ceramic magnesium oxide tapes has been developed as a method to produce flat sheets of sintered MgO that are thin and porous. Thickness of single layer tapes is in the range of 200-400 {micro}m with corresponding surface roughness values in the range of 10-20 {micro}m as measured by laser profilometry. Development of the tape casting technique required optimization of pretreatment for the starting magnesium oxide (MgO) powder as well as a detailed study of the casting slurry preparation and subsequent heat treatments for sintering and final tape flattening. Milling time of the ceramic powder, plasticizer, and binder mixture was identified as a primary factor affecting surface morphology of the tapes. In general, longer milling times resulted in green tapes with a noticeably smoother surface. This work demonstrates that meticulous control of the entire tape casting operation is necessary to obtain high-quality MgO tapes.
Date: February 1, 2008
Creator: Ayala, Alicia; Corral, Erica L.; Loehman, Ronald E.; Bencoe, Denise Nora; Reiterer, Markus & Shah, Raja A.
Object Type: Report
System: The UNT Digital Library