Final Results from the KTeV Experiment on the Decay K(L) ---> pi0 gamma gamma (open access)

Final Results from the KTeV Experiment on the Decay K(L) ---> pi0 gamma gamma

The authors report on a new measurement of the branching ratio B(K{sub L} {yields} {pi}{sup 0}{gamma}{gamma}) using the KTeV detector. They reconstruct 1982 events with an estimated background of 608, that results in B(K{sub L} {yields} {pi}{sup 0}{Gamma}{gamma}) = (1.29 {+-} 0.03{sub stat} {+-} 0.05{sub syst}) x 10{sup -6}. They also measure the parameter, a{sub V}, which characterizes the strength of vector meson exchange terms in this decay. They find a{sub V} = -0.31 {+-} 0.05{sub stat} {+-} 0.07{sub syst}. These results utilize the full KTeV data set collected from 1997 to 2000 and supersede earlier KTeV measurements of the branching ratio and a{sub V}.
Date: May 1, 2008
Creator: Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J. et al.
Object Type: Article
System: The UNT Digital Library
Foreign Investor Visas: Policies and Issues (open access)

Foreign Investor Visas: Policies and Issues

This report provides a brief legislative background, discussions of immigrant and nonimmigrant investors visas, a comparison of U.S. and Canadian immigrant investor programs, an analysis of the relationship between investment and migration, and finally a review of current issues.
Date: May 1, 2008
Creator: Haddal, Chad C.
Object Type: Report
System: The UNT Digital Library
Furthering Energy Security (open access)

Furthering Energy Security

This fact sheet provides a general summary of the goal, programs with the U.S. Department of Energy's Solar Energy Technologies Program, and a brief overview of the solar industry.
Date: May 1, 2008
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Future of Grid-Tied PV Business Models: What Will Happen When PV Penetration on the Distribution Grid is Significant? Preprint (open access)

Future of Grid-Tied PV Business Models: What Will Happen When PV Penetration on the Distribution Grid is Significant? Preprint

Eventually, distributed PV will become a more significant part of the generation mix. When this happens, it is expected that utilities will have to take on a more active role in the placement, operation and control of these systems. There are operational complexities and concerns of revenue erosion that will drive utilities into greater involvement of distributed PV and will create new business models. This report summarizes work done by Navigant Consulting Inc. for the National Renewable Energy Laboratory as part of the Department of Energy's work on Renewable System Integration. The objective of the work was to better understand the structure of these future business models and the research, development and demonstration (RD&D) required to support their deployment. This report describes potential future PV business models in terms of combinations of utility ownership and control of the PV assets, and the various relationships between end-users and third-party owners.
Date: May 1, 2008
Creator: Graham, S.; Katofsky, R.; Frantzis, L.; Sawyer, H. & Margolis, R.
Object Type: Article
System: The UNT Digital Library
Future of Liquid Biofuels for APEC Economies (open access)

Future of Liquid Biofuels for APEC Economies

This project was initiated by APEC Energy Working Group (EWG) to maximize the energy sector's contribution to the region's economic and social well-being through activities in five areas of strategic importance including liquid biofuels production and development.
Date: May 1, 2008
Creator: Milbrandt, A. & Overend, R. P.
Object Type: Report
System: The UNT Digital Library
Global Carbon Emissions in the Coming Decades: The Case of China (open access)

Global Carbon Emissions in the Coming Decades: The Case of China

China's annual energy-related carbon emissions surpassed those of the United States in In order to build a more robust understanding of China's energy-related carbon emissions, emissions after 2001? The divergence between actual and forecasted carbon emissions international trade, and central government policies in driving emissions growth. so greatly in error and what drove the rapid growth of China's energy-related carbon this article reviews the role of economic restructuring, urbanization, coal dependence, underscores the rapid changes that have taken place in China's energy system since 2001.
Date: May 1, 2008
Creator: Levine, Mark; Levine, Mark D. & Aden, Nathaniel T.
Object Type: Article
System: The UNT Digital Library
Global Climate Change: National Security Implications (open access)

Global Climate Change: National Security Implications

A report about climate change becoming a national security threat.
Date: May 2008
Creator: Pumphrey, Carolyn
Object Type: Report
System: The UNT Digital Library
Global Nuclear Energy Partnership Waste Treatment Baseline (open access)

Global Nuclear Energy Partnership Waste Treatment Baseline

The Global Nuclear Energy Partnership program (GNEP) is designed to demonstrate a proliferation-resistant and sustainable integrated nuclear fuel cycle that can be commercialized and used internationally. Alternative stabilization concepts for byproducts and waste streams generated by fuel recycling processes were evaluated and a baseline of waste forms was recommended for the safe disposition of waste streams. Waste forms are recommended based on the demonstrated or expected commercial practicability and technical maturity of the processes needed to make the waste forms, and performance of the waste form materials when disposed. Significant issues remain in developing technologies to process some of the wastes into the recommended waste forms, and a detailed analysis of technology readiness and availability may lead to the choice of a different waste form than what is recommended herein. Evolving regulations could also affect the selection of waste forms.
Date: May 1, 2008
Creator: Gombert, Dirk; Ebert, William; Marra, James; Jubin, Robert & Vienna, John
Object Type: Article
System: The UNT Digital Library
Grain-Boundary Physics in Polycrystalline Photovoltaic Materials: Preprint (open access)

Grain-Boundary Physics in Polycrystalline Photovoltaic Materials: Preprint

This paper describes a study of the atomic structure and electronic effects of grain boundaries in polycrystalline photovoltaic materials such as Si, CdTe, CuInSe2, and CuGaSe2.
Date: May 1, 2008
Creator: Yan, Y.; Jiang, C. S.; Wu, X. Z.; Noufi, R.; Wei, S. H. & Al-Jassim, M. M.
Object Type: Article
System: The UNT Digital Library
Hadronic Production of psi(2S) Cross section and Polarization (open access)

Hadronic Production of psi(2S) Cross section and Polarization

The hadronic production cross section and the polarization of {psi}(2S) meson are measured by using the data from p{bar p} collisions at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The datasets used correspond to integrated luminosity of 1.1 fb{sup -1} and 800 pb{sup -1}, respectively. The decay {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} is used to reconstruct {psi}(2S) mesons in the rapidity range |y({psi}(2S))| < 0.6. The coverage of the p{sub T} range is 2.0 GeV/c {le} p{sub T} ({psi}(2S)) < 30 GeV/c for the cross section analysis and pT {ge} 5 GeV/c for the polarization analysis. For events with p{sub T} ({psi}(2S)) > 2 GeV/c the integrated inclusive cross section multiplied by the branching ratio for dimuon decay is 3.17 {+-} 0.04 {+-} 0.28 nb . This result agrees with the CDF Run I measurement considering the increased center-of-mass energy from 1.8 TeV to 1.96 TeV. The polarization of the promptly produced {psi}(2S) mesons is found to be increasingly longitudinal as p{sub T} increases from 5 GeV/c to 30 GeV/c. The result is compared to contemporary theory models.
Date: May 1, 2008
Creator: Chung, Kwangzoo
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Heat Transfer Boundary Conditions in the RELAP5-3D Code (open access)

Heat Transfer Boundary Conditions in the RELAP5-3D Code

The heat transfer boundary conditions used in the RELAP5-3D computer program have evolved over the years. Currently, RELAP5-3D has the following options for the heat transfer boundary conditions: (a) heat transfer correlation package option, (b) non-convective option (from radiation/conduction enclosure model or symmetry/insulated conditions), and (c) other options (setting the surface temperature to a volume fraction averaged fluid temperature of the boundary volume, obtaining the surface temperature from a control variable, obtaining the surface temperature from a time-dependent general table, obtaining the heat flux from a time-dependent general table, or obtaining heat transfer coefficients from either a time- or temperature-dependent general table). These options will be discussed, including the more recent ones.
Date: May 1, 2008
Creator: Riemke, Richard A.; Davis, Cliff B. & Schultz, Richard R.
Object Type: Article
System: The UNT Digital Library
Help for the Developers of Control System Cyber Security Standards (open access)

Help for the Developers of Control System Cyber Security Standards

A Catalog of Control Systems Security: Recommendations for Standards Developers (Catalog), aimed at assisting organizations to facilitate the development and implementation of control system cyber security standards, has been developed. This catalog contains requirements that can help protect control systems from cyber attacks and can be applied to the Critical Infrastructures and Key Resources of the United States and other nations. The requirements contained in the catalog are a compilation of practices or various industry bodies used to increase the security of control systems from both physical and cyber attacks. They should be viewed as a collection of recommendations to be considered and judiciously employed, as appropriate, when reviewing and developing cyber security standards for control systems. The recommendations in the Catalog are intended to be broad enough to provide any industry using control systems the flexibility needed to develop sound cyber security standards specific to their individual security requirements.
Date: May 1, 2008
Creator: Evans, Robert P.
Object Type: Article
System: The UNT Digital Library
High-Efficiency Amorphous Silicon and Nanocrystalline Silicon-Based Solar Cells and Modules: Final Technical Progress Report, 30 January 2006 - 29 January 2008 (open access)

High-Efficiency Amorphous Silicon and Nanocrystalline Silicon-Based Solar Cells and Modules: Final Technical Progress Report, 30 January 2006 - 29 January 2008

United Solar Ovonic successfully used its spectrum-splitting a-Si:H/a-SiGe:H/a-SiGe:H triple-junction structure in their manufacturing plants, achieving a manufacturing capacity of 118 MW in 2007, and set up a very aggressive expansion plan to achieve grid parity.
Date: May 1, 2008
Creator: Guha, S. & Yang, J.
Object Type: Report
System: The UNT Digital Library
High Penetration, Grid Connected Photovoltaic Technology Codes and Standards: Preprint (open access)

High Penetration, Grid Connected Photovoltaic Technology Codes and Standards: Preprint

This paper reports the interim status in identifying and reviewing photovoltaic (PV) codes and standards (C&S) and related electrical activities for grid-connected, high-penetration PV systems with a focus on U.S. electric utility distribution grid interconnection.
Date: May 1, 2008
Creator: Basso, T. S.
Object Type: Article
System: The UNT Digital Library
High resolution upgrade of the ATF damping ring BPM system (open access)

High resolution upgrade of the ATF damping ring BPM system

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished in its first stage, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital downconversion techniques, digital signal processing, and also tests a new automatic gain error correction schema. The technical concept and realization, as well as preliminary results of beam studies are presented.
Date: May 1, 2008
Creator: Terunuma, N.; Urakawa, J.; Frisch, J.; May, J.; McCormick, D.; Nelson, J. et al.
Object Type: Article
System: The UNT Digital Library
High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films (open access)

High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.
Date: May 1, 2008
Creator: Farrell, R.; Pagan, V. R.; Kabulski, A.; Kuchibhatl, Sridhar; Harman, J.; Kasarla, K. R. et al.
Object Type: Report
System: The UNT Digital Library
Higher Education: Multiple Higher Education Tax Incentives Create Opportunities for Taxpayers to Make Costly Mistakes (open access)

Higher Education: Multiple Higher Education Tax Incentives Create Opportunities for Taxpayers to Make Costly Mistakes

Testimony issued by the Government Accountability Office with an abstract that begins "Federal assistance helps students and families pay for postsecondary education through several policy tools--grant and loan programs authorized by Title IV of the Higher Education Act of 1965 and more recently enacted tax preferences. This testimony summarizes our 2005 report and provides updates on (1) how Title IV assistance compares to that provided through the tax code (2) the extent to which tax filers effectively use education tax preferences, (3) potential benefits and costs of simplifying federal student aid, and (4) what is known about the effectiveness of federal assistance. This hearing is an opportunity to consider whether changes should be made in the government's overall strategy for providing such assistance or to the individual programs and tax provisions that provide the assistance. This statement is based on updates to previously published GAO work and reviews of relevant literature."
Date: May 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Holistic Evaluation of Lightweight Operating Systems using the PERCU Method (open access)

Holistic Evaluation of Lightweight Operating Systems using the PERCU Method

The scale of Leadership Class Systems presents unique challenges to the features and performance of operating system services. This paper reports results of comprehensive evaluations of two Light Weight Operating Systems (LWOS), Cray's Catamount Virtual Node (CVN) and Linux Environment (CLE) operating systems, on the exact same large-scale hardware. The evaluation was carried out over a 5-month period on NERSC's 19,480 core Cray XT-4, Franklin, using a comprehensive evaluation method that spans Performance, Effectiveness, Reliability, Consistency and Usability criteria for all major subsystems and features. The paper presents the results of the comparison between CVN and CLE, evaluates their relative strengths, and reports observations regarding the world's largest Cray XT-4 as well.
Date: May 1, 2008
Creator: Kramer, William T.C.; He, Yun (Helen); Carter, Jonathan; Glenski, Joseph; Rippe, Lynn & Cardo, Nicholas
Object Type: Report
System: The UNT Digital Library
Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates. (open access)

Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates.

Recently, the generalized method for calculation of the 16-element Green's function for analysis of surface acoustic waves has proven crucial to develop more sophisticated transducers. The generalized Green's function provides a precise relationship between the acoustic stresses and electric displacement on the three mechanical displacements and electric potential. This generalized method is able to account for mass loading effects which is absent in the effective permittivity approach. However, the calculation is numerically intensive and may lead to numerical instabilities when solving for both the eigenvalues and eigenvectors simultaneously. In this work, the general eigenvalue problem was modified to eliminate the numerical instabilities in the solving procedure. An algorithm is also presented to select the proper eigenvalues rapidly to facilitate analysis for all types of acoustic propagation. The 4 x 4 Green's functions and effective permittivities were calculated for materials supporting Rayleigh, leaky, and leaky longitudinal waves as demonstration of the method.
Date: May 1, 2008
Creator: Branch, Darren W.
Object Type: Report
System: The UNT Digital Library
Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix) (open access)

Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix)

This document describes the hydrogen transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA).
Date: May 1, 2008
Creator: Eudy, L. & Chandler, K.
Object Type: Report
System: The UNT Digital Library
Idaho National Laboratory Supervisory Control and Data Acquisition Intrusion Detection System (SCADA IDS) (open access)

Idaho National Laboratory Supervisory Control and Data Acquisition Intrusion Detection System (SCADA IDS)

Current Intrusion Detection System (IDS) technology is not suited to be widely deployed inside a Supervisory, Control and Data Acquisition (SCADA) environment. Anomaly- and signature-based IDS technologies have developed methods to cover information technology-based networks activity and protocols effectively. However, these IDS technologies do not include the fine protocol granularity required to ensure network security inside an environment with weak protocols lacking authentication and encryption. By implementing a more specific and more intelligent packet inspection mechanism, tailored traffic flow analysis, and unique packet tampering detection, IDS technology developed specifically for SCADA environments can be deployed with confidence in detecting malicious activity.
Date: May 1, 2008
Creator: Verba, Jared & Milvich, Michael
Object Type: Article
System: The UNT Digital Library
Impacts of Array Configuration on Land-Use Requirements for Large-Scale Photovoltaic Deployment in the United States: Preprint (open access)

Impacts of Array Configuration on Land-Use Requirements for Large-Scale Photovoltaic Deployment in the United States: Preprint

Land use is often cited as an important issue for renewable energy technologies. In this paper we examine the relationship between land-use requirements for large-scale photovoltaic (PV) deployment in the U.S. and PV-array configuration. We estimate the per capita land requirements for solar PV and find that array configuration is a stronger driver of energy density than regional variations in solar insolation. When deployed horizontally, the PV land area needed to meet 100% of an average U.S. citizen's electricity demand is about 100 m2. This requirement roughly doubles to about 200 m2 when using 1-axis tracking arrays. By comparing these total land-use requirements with other current per capita land uses, we find that land-use requirements of solar photovoltaics are modest, especially when considering the availability of zero impact 'land' on rooftops. Additional work is need to examine the tradeoffs between array spacing, self-shading losses, and land use, along with possible techniques to mitigate land-use impacts of large-scale PV deployment.
Date: May 1, 2008
Creator: Denholm, P. & Margolis, R. M.
Object Type: Article
System: The UNT Digital Library
An Improved model for the strain dependence of the superconducting properties of Nb3Sn (open access)

An Improved model for the strain dependence of the superconducting properties of Nb3Sn

We propose an improved model for the strain dependence of the superconducting properties of Nb{sub 3}Sn. The model is based on the three dimensional strain tensor and derived in terms of the first, second and third invariants, and improves an existing model that only includes the second invariant. The axial form of the new model accurately accounts for the experimentally observed dependence of the effective upper critical magnetic field (H*{sub c2}) on axial strain, i.e. a quasi-parabolic strain dependence, asymmetry, and an upturn at large compressive axial strain. An accurate model that accounts for the three dimensional nature of strain is important for scaling relations for the critical current that are used to model magnet performance based on wire measurements.
Date: May 1, 2008
Creator: Arbelaez, D.; Godeke, A. & Prestemon, S. O.
Object Type: Article
System: The UNT Digital Library
Inflation: Core vs. Headline (open access)

Inflation: Core vs. Headline

Inflation measures the rate of change in all prices. Maintaining low and stable inflation is one of the primary goals of macroeconomic policy. But how should inflation be measured? Policymakers, particularly at the Federal Reserve, often refer to core inflation in their policy decisions. Core inflation is commonly defined as a measure of inflation that omits changes in food and energy prices. However, several studies have failed to find core inflation to be a good forecaster of future inflation, casting doubt on the very rationale for relying on it. This report outlines the differences between core inflation and headline inflation.
Date: May 1, 2008
Creator: Labonte, Marc
Object Type: Report
System: The UNT Digital Library