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Joint Strike Fighter: Significant Challenges and Decisions Ahead (open access)

Joint Strike Fighter: Significant Challenges and Decisions Ahead

Testimony issued by the Government Accountability Office with an abstract that begins "The F-35 Lightning II, also known as the Joint Strike Fighter (JSF), is the Department of Defense's (DOD) most costly and ambitious aircraft acquisition, seeking to simultaneously develop and field three aircraft variants for the Air Force, Navy, Marine Corps, and eight international partners. The JSF is critical for recapitalizing tactical air forces and will require a long-term commitment to very large annual funding outlays. The current estimated investment is $323 billion to develop and procure 2,457 aircraft. This statement draws substantively from GAO's March 19, 2010 report (GAO-10-382). That report discusses JSF costs and schedules, warfighter requirements, manufacturing performance, procurement rates, and development testing plans. This statement also provides an updated analysis of relative costs and benefits from a second (or alternate) engine program. In previous years, we recommended, among other things, that DOD rethink plans to cut test resources, improve reliability of cost estimates, and reduce the number of aircraft procured before testing demonstrates their performance capabilities. In our March 2010 report, we recommended that DOD (1) make a new, comprehensive assessment of the program's costs and schedule and (2) reassess warfighter requirements. DOD concurred with …
Date: March 24, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Veterans' Disability Benefits: VA Has Improved Its Programs for Measuring Accuracy and Consistency, but Challenges Remain (open access)

Veterans' Disability Benefits: VA Has Improved Its Programs for Measuring Accuracy and Consistency, but Challenges Remain

Testimony issued by the Government Accountability Office with an abstract that begins "For years, in addition to experiencing challenges in making disability claims decisions more quickly and reducing its claims backlog, the Department of Veterans Affairs (VA) has faced challenges in improving the accuracy and consistency of its decisions. GAO was asked to discuss issues surrounding VA's Systematic Technical Accuracy Review (STAR) program, a disability compensation and pension quality assurance program, and possible ways, if any, this program could be improved. This statement focuses on actions VA has taken; including those in response to past GAO recommendations, to (1) address identified weaknesses with STAR and (2) improve efforts to monitor the consistency of claims decisions. This statement is based on GAO's prior work, which examined several aspects of STAR, as well as VA's consistency review activities, and on updated information GAO obtained from VA on quality assurance issues that GAO and VA's Office of Inspector General (OIG) have identified. GAO also reviewed VA's OIG March 2009 report on STAR. GAO is not making any new recommendations."
Date: March 24, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Information Security: Concerted Response Needed to Resolve Persistent Weaknesses (open access)

Information Security: Concerted Response Needed to Resolve Persistent Weaknesses

Testimony issued by the Government Accountability Office with an abstract that begins "Without proper safeguards, federal computer systems are vulnerable to intrusions by individuals who have malicious intentions and can obtain sensitive information. The need for a vigilant approach to information security has been demonstrated by the pervasive and sustained cyber attacks against the United States; these attacks continue to pose a potentially devastating impact to systems as well as the operations and critical infrastructures that they support. Concerned by reports of weaknesses in federal systems, Congress passed the Federal Information Security Management Act (FISMA), which authorized and strengthened information security program, evaluation, and annual reporting requirements for federal agencies. GAO was asked to testify on federal information security and agency efforts to comply with FISMA. This testimony summarizes (1) federal agencies' efforts to secure information systems and (2) opportunities to enhance federal cybersecurity. To prepare for this testimony, GAO analyzed its prior reports and those from 24 major federal agencies, their inspectors general, and the Office of Management and Budget (OMB)."
Date: March 24, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
The Optimist (Abilene, Tex.), Vol. 98, No. 45, Ed. 1 Wednesday, March 24, 2010 (open access)

The Optimist (Abilene, Tex.), Vol. 98, No. 45, Ed. 1 Wednesday, March 24, 2010

Bi-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: March 24, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 161, No. 5, Ed. 1 Wednesday, March 24, 2010 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 161, No. 5, Ed. 1 Wednesday, March 24, 2010

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: March 24, 2010
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 95, No. 34, Ed. 1 Wednesday, March 24, 2010 (open access)

North Texas Daily (Denton, Tex.), Vol. 95, No. 34, Ed. 1 Wednesday, March 24, 2010

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: March 24, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Appropriations Bills: What Are “General Provisions”? (open access)

Appropriations Bills: What Are “General Provisions”?

None
Date: March 24, 2010
Creator: Streeter, Sandy
Object Type: Report
System: The UNT Digital Library
Superresolution with Seismic Arrays using Empirical Matched Field Processing (open access)

Superresolution with Seismic Arrays using Empirical Matched Field Processing

Scattering and refraction of seismic waves can be exploited with empirical matched field processing of array observations to distinguish sources separated by much less than the classical resolution limit. To describe this effect, we use the term 'superresolution', a term widely used in the optics and signal processing literature to denote systems that break the diffraction limit. We illustrate superresolution with Pn signals recorded by the ARCES array in northern Norway, using them to identify the origins with 98.2% accuracy of 549 explosions conducted by closely-spaced mines in northwest Russia. The mines are observed at 340-410 kilometers range and are separated by as little as 3 kilometers. When viewed from ARCES many are separated by just tenths of a degree in azimuth. This classification performance results from an adaptation to transient seismic signals of techniques developed in underwater acoustics for localization of continuous sound sources. Matched field processing is a potential competitor to frequency-wavenumber and waveform correlation methods currently used for event detection, classification and location. It operates by capturing the spatial structure of wavefields incident from a particular source in a series of narrow frequency bands. In the rich seismic scattering environment, closely-spaced sources far from the observing array …
Date: March 24, 2010
Creator: Harris, D B & Kvaerna, T
Object Type: Article
System: The UNT Digital Library
Photoacoustically Measured Speeds of Sound of Liquid HBO2: On Unlocking the Fuel Potential of Boron (open access)

Photoacoustically Measured Speeds of Sound of Liquid HBO2: On Unlocking the Fuel Potential of Boron

Elucidation of geodynamic, geochemical, and shock induced processes is often limited by challenges to accurately determine molecular fluid equations of state (EOS). High pressure liquid state reactions of carbon species underlie physiochemical mechanisms such as differentiation of planetary interiors, deep carbon sequestration, propellant deflagration, and shock chemistry. Here we introduce a versatile photoacoustic technique developed to measure accurate and precise speeds of sound (SoS) of high pressure molecular fluids and fluid mixtures. SoS of an intermediate boron oxide, HBO{sub 2} are measured up to 0.5 GPa along the 277 C isotherm. A polarized Exponential-6 interatomic potential form, parameterized using our SoS data, enables EOS determinations and corresponding semi-empirical evaluations of > 2000 C thermodynamic states including energy release from bororganic formulations. Our thermochemical model propitiously predicts boronated hydrocarbon shock Hugoniot results.
Date: March 24, 2010
Creator: Bastea, S.; Crowhurst, J.; Armstrong, M. & Teslich, Nick, Jr.
Object Type: Article
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 89, Ed. 1 Wednesday, March 24, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 89, Ed. 1 Wednesday, March 24, 2010

Free weekly newspaper that includes business and classified advertising.
Date: March 24, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 33, No. 351, Ed. 1 Wednesday, March 24, 2010 (open access)

The Greensheet (Dallas, Tex.), Vol. 33, No. 351, Ed. 1 Wednesday, March 24, 2010

Free weekly newspaper that includes business and classified advertising.
Date: March 24, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
THE EFFECT OF ANOLYTE PRODUCT ACID CONCENTRATION ON HYBRID SULFUR CYCLE PERFORMANCE (open access)

THE EFFECT OF ANOLYTE PRODUCT ACID CONCENTRATION ON HYBRID SULFUR CYCLE PERFORMANCE

The Hybrid Sulfur (HyS) cycle (Fig. 1) is one of the simplest, all-fluids thermochemical cycles that has been devised for splitting water with a high-temperature nuclear or solar heat source. It was originally patented by Brecher and Wu in 1975 and extensively developed by Westinghouse in the late 1970s and early 1980s. As its name suggests, the only element used besides hydrogen and oxygen is sulfur, which is cycled between the +4 and +6 oxidation states. HyS comprises two steps. One is the thermochemical (>800 C) decomposition of sulfuric acid (H{sub 2}SO{sub 4}) to sulfur dioxide (SO{sub 2}), oxygen (O{sub 2}), and water. H{sub 2}SO{sub 4} = SO{sub 2} + 1/2 O{sub 2} + H{sub 2}O. The other is the SO{sub 2}-depolarized electrolysis of water to H{sub 2}SO{sub 4} and hydrogen (H{sub 2}), SO{sub 2} + 2 H{sub 2}O = H{sub 2}SO{sub 4} + H{sub 2}, E{sup o} = -0.156 V, explaining the 'hybrid' designation. These two steps taken together split water into H{sub 2} and O{sub 2} using heat and electricity. Researchers at the Savannah River National Laboratory (SRNL) and at the University of South Carolina (USC) have successfully demonstrated the use of proton exchange membrane (PEM) electrolyzers (Fig. …
Date: March 24, 2010
Creator: Gorensek, M. & Summers, W.
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF A GEOCHEMICAL MODEL FOR URANIUM TRANSPORT IN THE UNSATURATED AND SATURATED SEDIMENTS AT THE 200 WEST AREA OF THE US DEPARTMENT OF ENERGY HANFORD SITE WASHINGTON (SEPTEMBER 2004) (open access)

DEVELOPMENT OF A GEOCHEMICAL MODEL FOR URANIUM TRANSPORT IN THE UNSATURATED AND SATURATED SEDIMENTS AT THE 200 WEST AREA OF THE US DEPARTMENT OF ENERGY HANFORD SITE WASHINGTON (SEPTEMBER 2004)

Final Deliverable under GWP-HQ-LMT-02 contract for Hanford Sci. & Tech. Gp. to BHI. The scope of work covered laboratory analyses and gephysical logging for 299-W19-43 near the 200 West U Plant. Other isotopic analyses were conducted for holes around 216-U-1&2, including U-236.
Date: March 24, 2010
Creator: SC, ADAMS & SW, PETERSEN
Object Type: Report
System: The UNT Digital Library
MUST: A Scalable Approach to Runtime Error Detection in MPI Programs (open access)

MUST: A Scalable Approach to Runtime Error Detection in MPI Programs

The Message-Passing Interface (MPI) is large and complex. Therefore, programming MPI is error prone. Several MPI runtime correctness tools address classes of usage errors, such as deadlocks or nonportable constructs. To our knowledge none of these tools scales to more than about 100 processes. However, some of the current HPC systems use more than 100,000 cores and future systems are expected to use far more. Since errors often depend on the task count used, we need correctness tools that scale to the full system size. We present a novel framework for scalable MPI correctness tools to address this need. Our fine-grained, module-based approach supports rapid prototyping and allows correctness tools built upon it to adapt to different architectures and use cases. The design uses PnMPI to instantiate a tool from a set of individual modules. We present an overview of our design, along with first performance results for a proof of concept implementation.
Date: March 24, 2010
Creator: Hilbrich, T.; Schulz, M.; de Supinski, B. R. & Muller, M.
Object Type: Article
System: The UNT Digital Library
Review of High-Speed Fiber Optic Grating Sensors Systems (open access)

Review of High-Speed Fiber Optic Grating Sensors Systems

Fiber grating sensors can be used to support a wide variety of high speed measurement applications. This includes measurements of vibrations on bridges, traffic monitoring on freeways, ultrasonic detection to support non-destructive tests on metal plates and providing details of detonation events. This paper provides a brief overview of some of the techniques that have been used to support high speed measurements using fiber grating sensors over frequency ranges from 10s of kHz, to MHZ and finally toward frequencies approaching the GHz regime. Very early in the development of fiber grating sensor systems it was realized that a high speed fiber grating sensor system could be realized by placing an optical filter that might be a fiber grating in front of a detector so that spectral changes in the reflection from a fiber grating were amplitude modulated. In principal the only limitation on this type of system involved the speed of the output detector which with the development of high speed communication links moved from the regime of 10s of MHz toward 10s of GHz. The earliest deployed systems involved civil structures including measurements of the strain fields on composite utility poles and missile bodies during break tests, bridges and …
Date: March 24, 2010
Creator: Udd, E; Benterou, J; May, C; Mihailov, S J & Lu, P
Object Type: Article
System: The UNT Digital Library
Advanced Distillation Final Report (open access)

Advanced Distillation Final Report

The Advanced Distillation project was concluded on December 31, 2009. This U.S. Department of Energy (DOE) funded project was completed successfully and within budget during a timeline approved by DOE project managers, which included a one year extension to the initial ending date. The subject technology, Microchannel Process Technology (MPT) distillation, was expected to provide both capital and operating cost savings compared to conventional distillation technology. With efforts from Velocys and its project partners, MPT distillation was successfully demonstrated at a laboratory scale and its energy savings potential was calculated. While many objectives established at the beginning of the project were met, the project was only partially successful. At the conclusion, it appears that MPT distillation is not a good fit for the targeted separation of ethane and ethylene in large-scale ethylene production facilities, as greater advantages were seen for smaller scale distillations. Early in the project, work involved flowsheet analyses to discern the economic viability of ethane-ethylene MPT distillation and develop strategies for maximizing its impact on the economics of the process. This study confirmed that through modification to standard operating processes, MPT can enable net energy savings in excess of 20%. This advantage was used by ABB Lumus …
Date: March 24, 2010
Creator: Fanelli, Maddalena; Arora, Ravi; Tonkovich, Annalee; Marco, Jennifer & Rode, Ed
Object Type: Report
System: The UNT Digital Library
[Minutes of the TXSSAR Board of Managers Meeting: March 24-27, 2010] (open access)

[Minutes of the TXSSAR Board of Managers Meeting: March 24-27, 2010]

Minutes of the Texas Society of the Sons of the American Revolution (TXSSAR) Board of Managers meeting covering the general sessions, held March 24-27, 2010 at the Sheraton Grand DFW Airport Hotel, in Irving, Texas. It includes information about the committees and business covered by the attending members.
Date: 2010-03-24/2010-03-27
Creator: Rohrbough, Stephen
Object Type: Text
System: The UNT Digital Library
SMALL-SCALE SAFETY TEST SUMMARY REPORT-RDX (for triplicates) (open access)

SMALL-SCALE SAFETY TEST SUMMARY REPORT-RDX (for triplicates)

None
Date: March 24, 2010
Creator: Hsu, P C & Reynolds, J G
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 116, No. 12, Ed. 1 Wednesday, March 24, 2010 (open access)

The Clifton Record (Clifton, Tex.), Vol. 116, No. 12, Ed. 1 Wednesday, March 24, 2010

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: March 24, 2010
Creator: Henry, Mark
Object Type: Newspaper
System: The Portal to Texas History
Mesoscale Simulations of Particulate Flows with Parallel Distributed Lagrange Multiplier Technique (open access)

Mesoscale Simulations of Particulate Flows with Parallel Distributed Lagrange Multiplier Technique

Fluid particulate flows are common phenomena in nature and industry. Modeling of such flows at micro and macro levels as well establishing relationships between these approaches are needed to understand properties of the particulate matter. We propose a computational technique based on the direct numerical simulation of the particulate flows. The numerical method is based on the distributed Lagrange multiplier technique following the ideas of Glowinski et al. (1999). Each particle is explicitly resolved on an Eulerian grid as a separate domain, using solid volume fractions. The fluid equations are solved through the entire computational domain, however, Lagrange multiplier constrains are applied inside the particle domain such that the fluid within any volume associated with a solid particle moves as an incompressible rigid body. Mutual forces for the fluid-particle interactions are internal to the system. Particles interact with the fluid via fluid dynamic equations, resulting in implicit fluid-rigid-body coupling relations that produce realistic fluid flow around the particles (i.e., no-slip boundary conditions). The particle-particle interactions are implemented using explicit force-displacement interactions for frictional inelastic particles similar to the DEM method of Cundall et al. (1979) with some modifications using a volume of an overlapping region as an input to the …
Date: March 24, 2010
Creator: Kanarska, Y
Object Type: Article
System: The UNT Digital Library
X-ray photon-in/photon-out methods for chemical imaging (open access)

X-ray photon-in/photon-out methods for chemical imaging

Most interesting materials in nature are heterogeneous, so it is useful to have analytical techniques with spatial resolution sufficient to resolve these heterogeneities.This article presents the basics of X-ray photon-in/photon-out chemical imaging. This family of methods allows one to derive images reflectingthe chemical state of a given element in a complex sample, at micron or deep sub-micron scale. X-ray chemical imaging is relatively non-destructiveand element-selective, and requires minimal sample preparation. The article presents the basic concepts and some considerations of data takingand data analysis, along with some examples.
Date: March 24, 2010
Creator: Marcus, Matthew A.
Object Type: Article
System: The UNT Digital Library
Foreign Holdings of Federal Debt (open access)

Foreign Holdings of Federal Debt

This report presents current data on estimated ownership of U.S. Treasury securities and major holders of federal debt by country. Federal debt represents the accumulated balance of borrowing by the federal government. To finance federal borrowing, U.S. Treasury securities are sold to investors, directly from the Treasury or on the secondary market to individual private investors, financial institutions in the United States or overseas, and foreign, state, or local governments.
Date: March 24, 2010
Creator: Murray, Justin & Labonte, Marc
Object Type: Report
System: The UNT Digital Library
The Future of U.S. Trade Policy: An Analysis of Issues and Options for the 111th Congress (open access)

The Future of U.S. Trade Policy: An Analysis of Issues and Options for the 111th Congress

This report provides analysis of U.S. trade policy including factors that make up the current economic and political climate, grade issues, the depate over U.S. trade policy. It concludes with an examination of some of the options available to Congress and the pros and cons of each.
Date: March 24, 2010
Creator: Cooper, William H.
Object Type: Report
System: The UNT Digital Library
Federal Building and Facility Security (open access)

Federal Building and Facility Security

This report discusses the security of federal government buildings and facilities that affect not only the daily operations of the federal government but also the health, well-being, and safety of federal employees and the public.
Date: March 24, 2010
Creator: Reese, Shawn & Tong, Lorraine H.
Object Type: Report
System: The UNT Digital Library