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Nuclear Security: DOE Must Address Significant Issues to Meet the Requirements of the New Design Basis Threat (open access)

Nuclear Security: DOE Must Address Significant Issues to Meet the Requirements of the New Design Basis Threat

Testimony issued by the General Accounting Office with an abstract that begins "A successful terrorist attack on Department of Energy (DOE) sites containing nuclear weapons or the material used in nuclear weapons could have devastating consequences for the site and its surrounding communities. Because of these risks, DOE needs an effective safeguards and security program. A key component of an effective program is the design basis threat (DBT), a classified document that identifies, among other things, the potential size and capabilities of terrorist forces. The terrorist attacks of September 11, 2001, rendered the then-current DBT obsolete, resulting in DOE issuing a new version in May 2003. GAO (1) identified why DOE took almost 2 years to develop a new DBT, (2) analyzed the higher threat in the new DBT, and (3) identified remaining issues that need to be resolved in order for DOE to meet the threat contained in the new DBT."
Date: May 11, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Investigating Money Laundering And Terrorist Financing: Federal Law Enforcement Agencies Face Continuing Coordination Challenges (open access)

Investigating Money Laundering And Terrorist Financing: Federal Law Enforcement Agencies Face Continuing Coordination Challenges

Testimony issued by the General Accounting Office with an abstract that begins "Money laundering provides the fuel for terrorists, drug dealers, arms traffickers, and other criminals to operate and expand their activities. GAO focused on two issues. The first is whether the nation's annual National Money Laundering Strategy has served as a useful mechanism for guiding federal law enforcement efforts to combat money laundering and terrorist financing. Unless reauthorized by the Congress, the annual requirement ended with the 2003 strategy. The second issue is the implementation status of a May 2003 Memorandum of Agreement, signed by the Attorney General and the Secretary of Homeland Security, that was designed to enhance the coordination of terrorist financing investigations conducted by the Federal Bureau of Investigation (FBI) and the U.S. Immigration and Customs Enforcement (ICE)."
Date: May 11, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Diploma Mills: Federal Employees Have Obtained Degrees from Diploma Mills and Other Unaccredited Schools, Some at Government Expense (open access)

Diploma Mills: Federal Employees Have Obtained Degrees from Diploma Mills and Other Unaccredited Schools, Some at Government Expense

Testimony issued by the General Accounting Office with an abstract that begins "As requested, GAO conducted an investigation to determine whether the federal government has paid for degrees from diploma mills and other unaccredited postsecondary schools. Section 4107 of title 5, U. S. Code, only permits the federal government to pay for the cost of academic degree training provided by a college or university that is accredited by a nationally recognized accrediting body. GAO was also asked to determine whether federal employees who hold senior-level positions have degrees from diploma mills and other unaccredited schools. This report summarizes our investigative findings."
Date: May 11, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Homeland Security: First Phase of Visitor and Immigration Status Program Operating, but Improvements Needed (open access)

Homeland Security: First Phase of Visitor and Immigration Status Program Operating, but Improvements Needed

A letter report issued by the General Accounting Office with an abstract that begins "The Department of Homeland Security (DHS) has established a program--the United States Visitor and Immigrant Status Indicator Technology (US-VISIT)--to collect, maintain, and share information, including biometric identifiers, on selected foreign nationals who travel to the United States. By congressional mandate, DHS is to develop and submit for approval an expenditure plan for US-VISIT that satisfies certain conditions, including being reviewed by GAO. Among other things, GAO was asked to determine whether the plan satisfied these conditions, and to provide observations on the plan and DHS's program management."
Date: May 11, 2004
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Multi-Tube Power Leads Tower for Bepcii Ir Magnets. (open access)

Multi-Tube Power Leads Tower for Bepcii Ir Magnets.

A power lead tower containing the multi-tube power leads is designed and under fabrication for the superconducting IR quadrupole magnets in the Beijing Electron Position Collider Upgrade (BEPCII). The lead tower consists of six pairs of gas-cooled leads for seven superconducting coils at various operating currents. The power lead is designed in a modular fashion, which can be easily applied to suit different operating current. The end copper block of the tube lead has a large cold mass that provide a large time constant in case of cooling flow interruption. A novel cryogenic electrical isolator is used for the leads.
Date: May 11, 2004
Creator: Jia, L. X.; Zhang, X. B.; Wang, L.; Wang, T. H. & Yao, Z. L.
Object Type: Article
System: The UNT Digital Library
Thermal Fluid Modeling of Bepcii Ir Quadrupole Magnet Cryostat. (open access)

Thermal Fluid Modeling of Bepcii Ir Quadrupole Magnet Cryostat.

A pair of superconducting interaction region quadrupole magnets for BEPCII was designed and fabricated at Brookhaven National Laboratory, USA. The cryogenic system for the IR magnets was designed at Harbin Institute of Technology, China. This paper provides the results of thermal fluid modeling for the magnet cryostat. The numerical analyses were carried out for two types of cooling methods, the subcooled liquid helium and the supercritical helium flow. The pressure and temperature changes in the cooling circuits are given.
Date: May 11, 2004
Creator: Wang, L.; Tang, H. M.; Zhang, X. B.; Yang, G. D. & Jia, L. X.
Object Type: Article
System: The UNT Digital Library
Parallel Algebraic Multigrids for Structural mechanics (open access)

Parallel Algebraic Multigrids for Structural mechanics

This paper presents the results of a comparison of three parallel algebraic multigrid (AMG) preconditioners for structural mechanics applications. In particular, they are interested in investigating both the scalability and robustness of the preconditioners. Numerical results are given for a range of structural mechanics problems with various degrees of difficulty.
Date: May 11, 2004
Creator: Brezina, M; Tong, C & Becker, R
Object Type: Article
System: The UNT Digital Library
Rains County Leader (Emory, Tex.), Vol. 116, No. 47, Ed. 1 Tuesday, May 11, 2004 (open access)

Rains County Leader (Emory, Tex.), Vol. 116, No. 47, Ed. 1 Tuesday, May 11, 2004

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: May 11, 2004
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Top quark mass measurement at CDF Run-II (open access)

Top quark mass measurement at CDF Run-II

CDF has resumed the top quark mass measurement with upgraded detectors and Tevatron complex. High statistics should allow us to determine the top mass with an uncertainty of a few GeV/c{sup 2} by the end of Run II. The current measured value, using an integrated luminosity of {approx} 108 pb{sup -1}, is 177.5{sub -9.4}{sup +12.7} (stat.) {+-} 7.1(syst.) GeV/c{sup 2} (lepton + jets with one b-jet tagged mode: the current best mode), which is consistent with RunI measurements.
Date: May 11, 2004
Creator: Maruyama, T.
Object Type: Article
System: The UNT Digital Library
Geochemistry of Hydrofluoric Acid in Kaolinitic Soils (open access)

Geochemistry of Hydrofluoric Acid in Kaolinitic Soils

This document explores the geochemical reactions likely to occur when hydrofluoric acid is spilled on Savannah River Site (SRS) soil. In particular, we evaluate the potential of environmental damage from a one-time release of concentrated hydrofluoric acid into a trench. According to interviews with personnel involved, sometime between 1955 and 1960 drums of 50-60 per cent hydrofluoric acid were disposed in a trench in the Central Shops area. The method of disposal suggests that most of the acid would have been released at the time of burial. No evidence of drum disposal or acidic pH values was found. Therefore, the Soil and Groundwater Closure Projects group requested that we evaluate potential risk by examining the major geochemical interactions expected between hydrofluoric acid and soil. The geochemical calculations in this report were done with The Geochemist's Workbench (Registered). This program uses an extended Debye-Huckel method for calculating activity coefficients. The conclusions of this report are accurate, but some of the intermediate steps may have higher uncertainty. Hydrofluoric acid disposed in a trench in the area would have reacted with soil kaolinite to neutralize the pH to a value of about 4.2. Based on conservative assumptions, this would have occurred within the …
Date: May 11, 2004
Creator: DENHAM, MILES
Object Type: Report
System: The UNT Digital Library
Scientific Report (2002-2004) (open access)

Scientific Report (2002-2004)

OAK-B135 An overview of our work as well as two recent publications are contained in this scientific report. The work reported here revolves around the discovery of new coherent nonlinear kinetic waves in laser produced plasmas, we call KEEN waves (kinetic, electrostatic electron nonlinear waves), and optical mixing experiments on the Imega laser system at LLE with blue-green light for the exploration of ways to suppress parametric instabilities in long scale length, long pulsewidth laser-plasmas such as those which will be found on NIF or LMJ.
Date: May 11, 2004
Creator: Afeyan, Bedros
Object Type: Report
System: The UNT Digital Library
A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments (open access)

A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments

Titanium alloy degradation modes are reviewed in relation to their performance in repository environments. General corrosion, localized corrosion, stress corrosion cracking, hydrogen induced cracking, microbially influenced corrosion, and radiation-assisted corrosion of Ti alloys are considered. With respect to the Ti Grade 7 drip shields selected for emplacement in the repository at Yucca Mountain, general corrosion, hydrogen induced cracking, and radiation-assisted corrosion will not lead to failure within the 10,000 year regulatory period; stress corrosion cracking (in the absence of disruptive events) is of no consequence to barrier performance; and localized corrosion and microbially influenced corrosion are not expected to occur. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review.
Date: May 11, 2004
Creator: Hua, F.; Mon, K.; Pasupathi, P. & Gordon, G.
Object Type: Report
System: The UNT Digital Library
NEW CATHODE MATERIALS FOR INTERMEDIATE TEMPERATURE SOLID OXIDE FUEL CELLS (open access)

NEW CATHODE MATERIALS FOR INTERMEDIATE TEMPERATURE SOLID OXIDE FUEL CELLS

Operation of SOFCs at intermediate temperatures (500-800 C) requires new combinations of electrolyte and electrode materials that will provide both rapid ion transport across the electrolyte and electrode-electrolyte interfaces and efficient electrocatalysis of the oxygen reduction and fuel oxidation reactions. This project concentrates on materials and issues associated with cathode performance that are known to become limiting factors as the operating temperature is reduced. The specific objectives of the proposed research are to develop cathode materials that meet the electrode performance targets of 1.0 W/cm{sup 2} at 0.7 V in combination with YSZ at 700 C and with GDC, LSGM or bismuth oxide based electrolytes at 600 C. The performance targets imply an area specific resistance of {approx}0.5 {Omega}cm{sup 2} for the total cell. The research strategy is to investigate both established classes of materials and new candidates as cathodes, to determine fundamental performance parameters such as bulk diffusion, surface reactivity and interfacial transfer, and to couple these parameters to performance in single cell tests. The initial choices for study are perovskite oxides based on Sr substituted LaFeO{sub 3}, where significant data in single cell tests exists at PNNL for cathodes on both YSZ and CSO/YSZ, and of Ln{sub 2}NiO{sub …
Date: May 11, 2004
Creator: Jacobson, Allan J.
Object Type: Report
System: The UNT Digital Library
The Magnesium Branch of the Tetrapyrrole Biosynthetic Pathway (open access)

The Magnesium Branch of the Tetrapyrrole Biosynthetic Pathway

It should be noted that the focus of the research changed somewhat during the course of the current award. The initial focus is indicated by the title of the current grant, ''The Magnesium Branch of the Chlorophyll Biosynthetic Pathway''. During the current grant period, Dr. Robert Willows, a postdoctoral associate, joined the faculty of McQuarie University in Australia. When he left my lab, we decided that he should independently pursue research on structure/function relationships in Mg chelatase and that our laboratories would collaborate on regulatory studies of this enzyme. Also, during the current award period, I began collaborating with Dr. Ariane Atteia and Mr. Robert van Lis, who were at the time located at the Autonomous University of Mexico. Dr. Atteia has since joined my laboratory and Mr. van Lis will also do so when he obtains his Ph.D. in the near future. These individuals bring to the laboratory their interests and expertise in the respiratory components of Chlamydomonas and their desire to become experts in tetrapyrrole metabolism. Recently, in a collaboration with Dr. David Bollivar, a former postdoctoral associate who is now at Illinois Wesleyan University, and Dr. Caroline Walker, who was at Clemson University but has since left …
Date: May 11, 2004
Creator: Beale, S. I.
Object Type: Report
System: The UNT Digital Library
Performance characteristics of the Cray X1 and their implicationsfor application performance tuning (open access)

Performance characteristics of the Cray X1 and their implicationsfor application performance tuning

During the last decade the scientific computing community has optimized many applications for execution on superscalar computing platforms. The recent arrival of the Japanese Earth Simulator has revived interest in vector architectures especially in the US. It is important to examine how to port our current scientific applications to the new vector platforms and how to achieve high performance. The success of porting these applications will also influence the acceptance of new vector architectures. In this paper, we first investigate the memory performance characteristics of the Cray X1, a recently released vector platform, and determine the most influential performance factors. Then, we examine how to optimize applications tuned on superscalar platforms for the Cray X1 using its performance characteristics as guidelines. Finally, we evaluate the different types of optimizations used, the effort for their implementations, and whether they provide any performance benefits when ported back to superscalar platforms.
Date: May 11, 2004
Creator: Shan, Hogzhang & Strohmaier, Erich
Object Type: Article
System: The UNT Digital Library
Type Ia supernova rate at a redshift of ~;0.1 (open access)

Type Ia supernova rate at a redshift of ~;0.1

We present the type Ia rate measurement based on two EROS supernova search campaigns (in 1999 and 2000). Sixteen supernovae identified as type Ia were discovered. The measurement of the detection efficiency, using a Monte Carlo simulation, provides the type Ia supernova explosion rate at a redshift {approx} 0.13. The result is 0.125{sub -0.034-0.028}{sup +0.044+0.028} h{sub 70}{sup 2} SNu where 1 SNu = 1 SN/10{sup 10} L{sub {circle_dot}}{sup B}/century. This value is compatible with the previous EROS measurement (Hardin et al. 2000), done with a much smaller sample, at a similar redshift. Comparison with other values at different redshifts suggests an evolution of the type Ia supernova rate.
Date: May 11, 2004
Creator: Blanc, G.; Afonso, C.; Alard, C.; Albert, J. N.; Aldering, G.; Amadon, A. et al.
Object Type: Article
System: The UNT Digital Library
Initial Operation of the NSTX Fast Tangential Soft X-Ray Camera (open access)

Initial Operation of the NSTX Fast Tangential Soft X-Ray Camera

Fast, two-dimensional, soft x-ray imaging is a powerful technique for the study of MHD instabilities in tokamak plasmas. We have constructed an ultra-fast frame rate soft x-ray camera for the National Spherical Torus Experiment. It is based on a recently developed 64 x 64 pixel CCD camera capable of capturing 300 frames at up to 500,000 frames per second. A pinhole aperture images the plasma soft x-ray emission (0.2-10 keV) onto a P47 scintillator deposited on a fiber-optic faceplate; the scintillator visible light output is detected and amplified by a demagnifying image intensifier and lens-coupled to the CCD chip. A selection of beryllium foils provides discrimination of low-energy emission. The system is installed on NSTX with a wide-angle tangential view of the plasma. Initial plasma data and an assessment of the system performance are presented.
Date: May 11, 2004
Creator: Stratton, B. C.; Feder, R.; Von Goeler, S.; Renda, G. F.; Lowrance, J. L. & Mastrocola, V. J.
Object Type: Report
System: The UNT Digital Library
Effects of Radiative Recombination and Photon Recycling on Minority Carrier Lifetime in Epitaxial GaINAsSb Lattice-matched to GaSb (open access)

Effects of Radiative Recombination and Photon Recycling on Minority Carrier Lifetime in Epitaxial GaINAsSb Lattice-matched to GaSb

None
Date: May 11, 2004
Creator: Anikeev, S.; Donetsky, D.; Belenky, G.; Luryl, S.; Wang, C. A.; Shiau, D. A. et al.
Object Type: Report
System: The UNT Digital Library
pH and resistivity of the BCP mix diluted in UPW (open access)

pH and resistivity of the BCP mix diluted in UPW

Etching plays an important role in the production of superconducting cavities (SRF). As other laboratories engaged in RF superconductivity R and D did, FNAL is also developing a facility for the chemical etching of niobium (Nb) cavities. Two techniques are common accepted for cavity etching: (1) chemical etching--buffered chemical polishing (BCP); and (2) Electropolishing (EP). Among them, at FNAL it was decided to pursue chemical etching, which is considered a reliable technique tested by several labs for many years. In the past, numerous mixtures of acids have been tested leading to the actual buffered chemical polishing mix (BCP) characterized by the following composition by volume: 1 of HF 49 %wt; 1 of HNO{sub 3} 69.5 %wt; 2 of H{sub 3}PO{sub 4} 85 %wt. Because of the dangerous nature of the chemicals involved, safety considerations require the development of a proper process and a reliable control algorithm. For the post-processing rinsing of the cavities, one needs to know the expected pH of the water used to rinse the cavity. On the other hand, for early detection of leaks in the hydraulic system, which is done by measuring the conductivity of the rinsing water used in the process, one needs to understand …
Date: May 11, 2004
Creator: al., Cristian Boffo et
Object Type: Report
System: The UNT Digital Library
Hybrid Back Surface Reflector GaInAsSb Thermophotovoltaic Devices (open access)

Hybrid Back Surface Reflector GaInAsSb Thermophotovoltaic Devices

Back surface reflectors have the potential to improve thermophotovoltaic (TPV) device performance though the recirculation of infrared photons. The ''hybrid'' back-surface reflector (BSR) TPV cell approach allows one to construct BSRs for TPV devices using conventional, high efficiency, GaInAsSb-based TPV material. The design, fabrication, and measurements of hybrid BSR-TPV cells are described. The BSR was shown to provide a 4 mV improvement in open-circuit voltage under a constant shortcircuit current, which is comparable to the 5 mV improvement theoretically predicted. Larger improvements in open-circuit voltage are expected in the future with materials improvements.
Date: May 11, 2004
Creator: Huang, R. K.; Wang, C. A.; Connors, M. K.; Turner, G. W. & Dashiell, M.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 162, Ed. 1 Tuesday, May 11, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 162, Ed. 1 Tuesday, May 11, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: May 11, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
[Funeral Program for William Thomas Dorsey, Jr., May 11, 2004] (open access)

[Funeral Program for William Thomas Dorsey, Jr., May 11, 2004]

Funeral program for Mr. William Thomas Dorsey, Jr., born March 26, 1936 and died June 6, 2004. The funeral was held May 11, 2004 at True Vision Baptist Church, officiated by Rev. Hubert Griffin. Funeral arrangements were made through Carter-Taylor-Williams Mortuary and he was buried in Ft. Sam Houston National Cemetery in San Antonio, Texas.
Date: May 11, 2004
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
CRYOGENIC SYSTEM FOR BEPCII SRF CAVITY, IR QUADRUPOLE AND DETECTOR SOLENOID MAGNETS. (open access)

CRYOGENIC SYSTEM FOR BEPCII SRF CAVITY, IR QUADRUPOLE AND DETECTOR SOLENOID MAGNETS.

Beijing Electron-Positron Collider Upgrade (BEPCII) requires three types of superconducting facilities, including one pair of SRF cavities, one pair of interaction region quadrupole magnets, and one detector solenoid magnet. The cryo-plant for BEPCII has a total cooling capacity of 1kW at 4.5K, which is composed of two separate helium refrigerators of 500W each. Two refrigerators share the same gas storage and recovery system. The engineering design for the cryogenic systems, including power leads, control dewars, subcooler, cryogenic valve boxes, cryogenic transfer-lines and cryogenic controls, is completed. The production of its subsystem is under way. This paper summarizes the progress in cryogenics of the BEPCII project.
Date: May 11, 2004
Creator: JIA,J. X. & L., WANG.
Object Type: Article
System: The UNT Digital Library
Proteomic Characterization of Host Response to Yersinia pestis (open access)

Proteomic Characterization of Host Response to Yersinia pestis

Host-pathogen interactions result in protein expression changes within both the host and the pathogen. Here, results from proteomic characterization of host response following exposure to Yersinia pestis, the causative agent of plague, and to two near neighbors, Y. pseudotuberculosis and Y. enterocolitica, are reported. Human monocyte-like cells were chosen as a model for macrophage immune response to pathogen exposure. Two-dimensional electrophoresis followed by mass spectrometry was used to identify host proteins with differential expression following exposure to these three closely related Yersinia species. This comparative proteomic characterization of host response clearly shows that host protein expression patterns are distinct for the different pathogen exposures, and contributes to further understanding of Y. pestis virulence and host defense mechanisms. This work also lays the foundation for future studies aimed at defining biomarkers for presymptomatic detection of plague.
Date: May 11, 2004
Creator: Chromy, B.; Perkins, J.; Heidbrink, J.; Gonzales, A.; Murhpy, G.; Fitch, J. P. et al.
Object Type: Article
System: The UNT Digital Library