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Federal Reserve Banks: Areas for Improvement in Information Security Controls (open access)

Federal Reserve Banks: Areas for Improvement in Information Security Controls

Correspondence issued by the Government Accountability Office with an abstract that begins "In connection with fulfilling our requirement to audit the financial statements of the U.S. government, we audited and reported on the Schedules of Federal Debt Managed by the Bureau of the Public Debt (BPD) for the fiscal years ended September 30, 2009 and 2008. As part of these audits, we performed a review of the general and application information security controls over key financial systems maintained and operated by the Federal Reserve Banks (FRB) on behalf of the Department of the Treasury's (Treasury) BPD relevant to the Schedule of Federal Debt. As we reported in connection with our audit of the Schedules of Federal Debt for the fiscal years ended September 30, 2009 and 2008, we concluded that BPD maintained, in all material respects, effective internal control relevant to the Schedule of Federal Debt related to financial reporting and compliance with applicable laws and regulations as of September 30, 2009, that provided reasonable assurance that misstatements, losses, or noncompliance material in relation to the Schedule of Federal Debt would be prevented or detected on a timely basis. However, we found deficiencies involving information security controls that we do …
Date: April 21, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Next Generation Air Transportation System: Challenges with Partner Agency and FAA Coordination Continue, and Efforts to Integrate Near-, Mid-, and Long-term Activities Are Ongoing (open access)

Next Generation Air Transportation System: Challenges with Partner Agency and FAA Coordination Continue, and Efforts to Integrate Near-, Mid-, and Long-term Activities Are Ongoing

Testimony issued by the Government Accountability Office with an abstract that begins "To prepare for future air traffic growth, the Federal Aviation Administration (FAA), including its Joint Planning and Development Office (JPDO) and Air Traffic Organization, is planning and implementing the Next Generation Air Transportation System (NextGen) in partnership with other federal agencies, such as the Departments of Commerce, Defense, and Homeland Security, and the aviation industry. NextGen will transform the current radar-based air traffic control system into a satellite-based system. As FAA begins implementing near-and midterm NextGen capabilities, a key challenge will be the extent to which FAA is able to integrate near and midterm improvements (those between 2012 and 2018) with long-term plans (beyond 2018). Furthermore, coordination among federal partner agencies and among various lines of business within FAA is important to ensure that NextGen implementation efforts are aligned. GAO's testimony focuses on (1) current mechanisms for and challenges to coordination among FAA and its partner agencies in implementing NextGen, (2) challenges and ongoing efforts to improve coordination across offices within FAA, and (3) issues related to integrating near- and midterm implementation plans with long-term NextGen plans. This statement is based on past and ongoing GAO work, and …
Date: April 21, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
National Flood Insurance Program: Continued Actions Needed to Address Financial and Operational Issues (open access)

National Flood Insurance Program: Continued Actions Needed to Address Financial and Operational Issues

Testimony issued by the Government Accountability Office with an abstract that begins "The National Flood Insurance Program (NFIP), established in 1968, provides policyholders with insurance coverage for flood damage. The Federal Emergency Management Agency (FEMA) within the Department of Homeland Security is responsible for managing NFIP. Unprecedented losses from the 2005 hurricane season and NFIP's periodic need to borrow from the U.S. Treasury to pay flood insurance claims have raised concerns about the program's long-term financial solvency. Because of these concerns and NFIP's operational issues, NFIP has been on GAO's high-risk list since March 2006. As of April 2010, NFIP's debt to Treasury stood at $18.8 billion. The Subcommittee asked GAO to discuss (1) NFIP's financial challenges, (2) FEMA's operational and management challenges, and (3) actions needed to address these challenges. In preparing this statement, GAO relied on its past work on NFIP and GAO's ongoing review of FEMA's management of NFIP focused on information technology and contractor oversight issues."
Date: April 21, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 138, Ed. 1 Wednesday, April 21, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 138, Ed. 1 Wednesday, April 21, 2010

Free weekly newspaper that includes business and classified advertising.
Date: April 21, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Optimist (Abilene, Tex.), Vol. 98, No. 51, Ed. 1 Wednesday, April 21, 2010 (open access)

The Optimist (Abilene, Tex.), Vol. 98, No. 51, Ed. 1 Wednesday, April 21, 2010

Bi-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: April 21, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 161, No. 9, Ed. 1 Wednesday, April 21, 2010 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 161, No. 9, Ed. 1 Wednesday, April 21, 2010

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: April 21, 2010
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 95, No. 50, Ed. 1 Wednesday, April 21, 2010 (open access)

North Texas Daily (Denton, Tex.), Vol. 95, No. 50, Ed. 1 Wednesday, April 21, 2010

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: April 21, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Rambler (Fort Worth, Tex.), Vol. 93, No. 11, Ed. 1 Wednesday, April 21, 2010 (open access)

The Rambler (Fort Worth, Tex.), Vol. 93, No. 11, Ed. 1 Wednesday, April 21, 2010

Weekly student newspaper from Texas Wesleyan University in Fort Worth, Texas that includes campus and local news along with advertising.
Date: April 21, 2010
Creator: Resendez, Jonathan
Object Type: Newspaper
System: The Portal to Texas History
The Rambler (Fort Worth, Tex.), Vol. 93, No. 11, Ed. 1 Wednesday, April 21, 2010 (open access)

The Rambler (Fort Worth, Tex.), Vol. 93, No. 11, Ed. 1 Wednesday, April 21, 2010

Weekly student newspaper from Texas Wesleyan University in Fort Worth, Texas that includes campus and local news along with advertising.
Date: April 21, 2010
Creator: Resendez, Jonathan
Object Type: Newspaper
System: The Portal to Texas History
Bridging silyl groups in sigma-bond metathesis and [1, 2] shifts. An experimental and computational study of the reaction between cerium metallocenes and MeOSiMe3 (open access)

Bridging silyl groups in sigma-bond metathesis and [1, 2] shifts. An experimental and computational study of the reaction between cerium metallocenes and MeOSiMe3

The reaction of Cp'2CeH (Cp' = 1,2,4-(Me3C)3C5H2 ) with MeOSiMe3 gives Cp'2CeOMe and HSiMe3 and the reaction of the metallacycle, Cp'[(Me3C)2C5H2C(Me) 2CH2]Ce, with MeOSiMe3 yields Cp'2CeOCH2SiMe3, formed from hypothetical Cp'2CeCH2OSiMe3 by a [1, 2] shift also known as a silyl-Wittig rearrangement. Although both cerium products are alkoxides, they are formed by different pathways. DFT calculations on the reaction of the model metallocene, Cp2CeH, and MeOSiMe3 show that the lowest energy pathway is a H for OMe exchange at Ce that occurs by way of a sigma-bond metathesis transition state as SiMe3 exchanges partners. The formation of Cp2CeOCH2SiMe3 occurs by way of a low activation barrier [1, 2]shift of the SiMe3 group in Cp2CeCH2OSiMe3. Calculations on a model metallacycle, Cp[C5H4C(Me)2CH2]Ce, show that the metallacycle favors CH bond activation over sigma-bond metathesis involving the transfer of the SiMe3 group in good agreement with experiment. The sigma-bond metathesis involving the transfer of SiMe3 and the [1, 2]shift of SiMe3 reactions have in common a pentacoordinate silicon at the transition states. A molecular orbital analysis illustrates the connection between these two Si-O bond cleavage reactions and traces the reason why they occur for a silyl but not for an alkyl group to the difference …
Date: April 21, 2010
Creator: Werkema, Evan; Yahia, Ahmed; Maron, Laurent; Eisenstein, Odile & Andersen, Richard
Object Type: Article
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 137, Ed. 1 Wednesday, April 21, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 137, Ed. 1 Wednesday, April 21, 2010

Free weekly newspaper that includes business and classified advertising.
Date: April 21, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 34, No. 15, Ed. 1 Wednesday, April 21, 2010 (open access)

The Greensheet (Dallas, Tex.), Vol. 34, No. 15, Ed. 1 Wednesday, April 21, 2010

Free weekly newspaper that includes business and classified advertising.
Date: April 21, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Extracellular oxidative metabolism of wood decay fungi (open access)

Extracellular oxidative metabolism of wood decay fungi

Substantial progress has been made toward understanding the fundamental physiology and genetics of wood decay fungi, microbes that are capable of degrading all major components of plant cell walls. Efficient utilization of lignocellulosic biomass has been hampered in part by limitations in our understanding of enzymatic mechanisms of plant cell wall degradation. This is particularly true of woody substrates where accessibility and high lignin content substantially complicate enzymatic 'deconstruction'. The interdisciplinary research has illuminated enzymatic mechanisms essential for the conversion of lignocellulosics to simple carbohydrates and other small molecular weight products. Progress was in large part dependent on substantial collaborations with the Department of Energy's Joint Genome Institute (JGI) in Walnut Creek and Los Alamos, as well as the Catholic University, Santiago, Chile, the Royal Institute of Technology, Stockholm, the University of Minnesota, St. Paul, and colleagues at the University of Wisconsin and the Forest Products Laboratory. Early accomplishments focused on the development of experimental tools (2, 7, 22, 24-26, 32) and characterization of individual genes and enzymes (1, 3-5, 8, 9, 11, 14, 15, 17, 18, 23, 27, 33). In 2004, the genome of the most intensively studied lignin-degrading fungus, Phanerochaete chrysosporium, was published (21). This milestone lead to …
Date: April 21, 2010
Creator: Cullen, Daniel
Object Type: Report
System: The UNT Digital Library
Self-guided Laser Wakefield Acceleration Beyond 1 GeV using Ionization-induced Injection (open access)

Self-guided Laser Wakefield Acceleration Beyond 1 GeV using Ionization-induced Injection

None
Date: April 21, 2010
Creator: Clayton, C. E.; Ralph, J. E.; Albert, F.; Fonseca, R. A.; Glenzer, S. H.; Joshi, C. et al.
Object Type: Article
System: The UNT Digital Library
Probing Radiation Damage in Plutonium Alloys with Multiple Measurement Techniques (open access)

Probing Radiation Damage in Plutonium Alloys with Multiple Measurement Techniques

A material subjected to radiation damage will usually experience changes in its physical properties. Measuring these changes in the physical properties provides a basis to study radiation damage in a material which is important for a variety of real world applications from reactor materials to semiconducting devices. When investigating radiation damage, the relative sensitivity of any given property can vary considerably based on the concentration and type of damage present as well as external parameters such as the temperature and starting material composition. By measuring multiple physical properties, these differing sensitivities can be leveraged to provide greater insight into the different aspects of radiation damage accumulation, thereby providing a broader understanding of the mechanisms involved. In this report, self-damage from {alpha}-particle decay in Pu is investigated by measuring two different properties: magnetic susceptibility and resistivity. The results suggest that while the first annealing stage obeys second order chemical kinetics, the primary mechanism is not the recombination of vacancy-interstitial close pairs.
Date: April 21, 2010
Creator: McCall, S K; Fluss, M J & Chung, B W
Object Type: Article
System: The UNT Digital Library
SciDAC's Earth System Grid Center for Enabling Technologies Semi-Annual Progress Report for the Period October 1, 2009 through March 31, 2010 (open access)

SciDAC's Earth System Grid Center for Enabling Technologies Semi-Annual Progress Report for the Period October 1, 2009 through March 31, 2010

This report summarizes work carried out by the ESG-CET during the period October 1, 2009 through March 31, 2009. It includes discussion of highlights, overall progress, period goals, collaborations, papers, and presentations. To learn more about our project, and to find previous reports, please visit the Earth System Grid Center for Enabling Technologies (ESG-CET) website. This report will be forwarded to the DOE SciDAC program management, the Office of Biological and Environmental Research (OBER) program management, national and international collaborators and stakeholders (e.g., the Community Climate System Model (CCSM), the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5), the Climate Science Computational End Station (CCES), the SciDAC II: A Scalable and Extensible Earth System Model for Climate Change Science, the North American Regional Climate Change Assessment Program (NARCCAP), and other wide-ranging climate model evaluation activities).
Date: April 21, 2010
Creator: Williams, D. N.; Foster, I. T.; Middleton, D. E.; Ananthakrishnan, R.; Siebenlist, F.; Shoshani, A. et al.
Object Type: Report
System: The UNT Digital Library
Influence of molecular ordering on electrical and friction properties of omega-(trans-4-stilbene)alkylthiol self-assembled monolayers on Au (111) (open access)

Influence of molecular ordering on electrical and friction properties of omega-(trans-4-stilbene)alkylthiol self-assembled monolayers on Au (111)

The electrical and friction properties of omega-(trans-4-stilbene)alkylthiol self-assembled monolayers (SAMs) on Au(111) were investigated using atomic force microscopy (AFM) and near edge x-ray absorption fine structure spectroscopy (NEXAFS). The sample surface was uniformly covered with a molecular film consisting of very small grains. Well-ordered and flat monolayer islands were formed after the sample was heated in nitrogen at 120 oC for 1 h. While lattice resolved AFM images revealed a crystalline phase in the islands, the area between islands showed no order. The islands exhibit substantial reduction (50percent) in friction, supporting the existence of good ordering. NEXAFS measurements revealed an average upright molecular orientation in the film, both before and after heating, with a narrower tilt-angle distribution for the heated fim. Conductance-AFM measurements revealed a two orders of magnitude higher conductivity on the ordered islands than on the disordered phase. We propose that the conductance enhancement is a result of a better pi-pi stacking between the trans-stilbene molecular units as a result of improved ordering in islands.
Date: April 21, 2010
Creator: Qi, Yabing; Liu, Xiaosong; Hendriksen, B.L.M.; Navarro, V.; Park, Jeong Y.; Ratera, Imma et al.
Object Type: Article
System: The UNT Digital Library
High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant (open access)

High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

High pressure deflagration rate measurements of a unique ammonium perchlorate (AP) based propellant are required to design the base burn motor for a Raytheon weapon system. The results of these deflagration rate measurements will be key in assessing safety and performance of the system. In particular, the system may experience transient pressures on the order of 100's of MPa (10's kPSI). Previous studies on similar AP based materials demonstrate that low pressure (e.g. P < 10 MPa or 1500 PSI) burn rates can be quite different than the elevated pressure deflagration rate measurements (see References and HPP results discussed herein), hence elevated pressure measurements are necessary in order understand the deflagration behavior under relevant conditions. Previous work on explosives have shown that at 100's of MPa some explosives will transition from a laminar burn mechanism to a convective burn mechanism in a process termed deconsolidative burning. The resulting burn rates that are orders-of-magnitude faster than the laminar burn rates. Materials that transition to the deconsolidative-convective burn mechanism at elevated pressures have been shown to be considerably more violent in confined heating experiments (i.e. cook-off scenarios). The mechanisms of propellant and explosive deflagration are extremely complex and include both chemical, and …
Date: April 21, 2010
Creator: Glascoe, E A & Tan, N
Object Type: Report
System: The UNT Digital Library
A new method to generate dust with astrophysical properties (open access)

A new method to generate dust with astrophysical properties

In interstellar and interplanetary space, the size distribution and composition of dust grains play an important role. For example, dust grains determine optical and ultraviolet extinction levels in astronomical observations, dominate the cooling rate of our Galaxy, and sets the thermal balance and radiative cooling rates in molecular clouds, which are the birth place of stars. Dust grains are also a source of damage and failure to space hardware and thus present a hazard to space flight. To model the size distribution and composition of dust grains, and their effect in the above scenarios, it is vital to understand the mechanism of dust-shock interaction. We demonstrate a new experiment which employs a laser to subject dust grains to pressure spikes similar to those of colliding astrophysical dust, and which accelerates the grains to astrophysical velocities. The new method generates much larger data sets than earlier methods; we show how large quantities (thousands) of grains are accelerated at once, rather than accelerating individual grains, as is the case of earlier methods using electric fields.
Date: April 21, 2010
Creator: Hansen, J. F.; van Breugel, W.; Bringa, E. M.; Graham, G. A.; Remington, B. A.; Taylor, E. A. et al.
Object Type: Article
System: The UNT Digital Library
SECONDARY ELECTRON TRAJECTORIES IN HIGH-GRADIENT VACUUM INSULATORS WITH FAST HIGH-VOLTAGE PULSES (open access)

SECONDARY ELECTRON TRAJECTORIES IN HIGH-GRADIENT VACUUM INSULATORS WITH FAST HIGH-VOLTAGE PULSES

Vacuum insulators composed of alternating layers of metal and dielectric, known as high-gradient insulators (HGIs), have been shown to withstand higher electric fields than conventional insulators. Primary or secondary electrons (emitted from the insulator surface) can be deflected by magnetic fields from external sources, the high-current electron beam, the conduction current in the transmission line, or the displacement current in the insulator. These electrons are deflected either toward or away from the insulator surface and this affects the performance of the vacuum insulator. This paper shows the effects of displacement current from short voltage pulses on the performance of high gradient insulators. Generally, vacuum insulator failure is due to surface flashover, initiated by electrons emitted from a triple junction. These electrons strike the insulator surface thus producing secondary electrons, and can lead to a subsequent electron cascade along the surface. The displacement current in the insulator can deflect electrons either toward or away from the insulator surface, and affects the performance of the vacuum insulator when the insulator is subjected to a fast high-voltage pulse. Vacuum insulators composed of alternating layers of metal and dielectric, known as high-gradient insulators (HGIs), have been shown to withstand higher electric fields than conventional …
Date: April 21, 2010
Creator: Chen, Y.; Blackfield, D.; Nelson, S. D. & Poole, B.
Object Type: Article
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 116, No. 15, Ed. 1 Wednesday, April 21, 2010 (open access)

The Clifton Record (Clifton, Tex.), Vol. 116, No. 15, Ed. 1 Wednesday, April 21, 2010

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: April 21, 2010
Creator: Henry, Mark
Object Type: Newspaper
System: The Portal to Texas History
What's the Difference?--Comparing U.S. and Chinese Trade Data (open access)

What's the Difference?--Comparing U.S. and Chinese Trade Data

This report provides a comparison of U.S. and Chinese trade data. The U.S. trade deficit with the People's Republic of China (China) remains a major source of bilateral tension. Members of Congress and other U.S. government officials often point to the bilateral trade imbalance as evidence that China is not competing fairly in the global market.
Date: April 21, 2010
Creator: Martin, Michael F.
Object Type: Report
System: The UNT Digital Library
Monitoring and Verification in Arms Control (open access)

Monitoring and Verification in Arms Control

This report reviews some of the monitoring and verification provisions in the new START (Strategic Offensive Reduction Treaty) Treaty and compares these with some of the provisions in the original START Treaty. It focuses, specifically, on differences between the treaties in the provisions governing the exchange of data -- known as telemetry -- generated during missle flight tests; provisions governing the monitoring of mobile intercontinental ballistic missiles (ICBMs); and differences in the numbers and types of on-site inspections.
Date: April 21, 2010
Creator: Woolf, Amy F.
Object Type: Report
System: The UNT Digital Library
Speed of Presidential and Senate Actions on Supreme Court Nominations, 1900-2010 (open access)

Speed of Presidential and Senate Actions on Supreme Court Nominations, 1900-2010

This report provides information on the amount of time taken to act on all Supreme Court nominations occurring between 1900 and 2010. It focuses on the actual amounts of time that Presidents and the Senate have taken to act after learning about vacancies, selections, etc. (as opposed to the elapsed time between official points in the process).
Date: April 21, 2010
Creator: Garrett, R. Sam & Rutkus, Denis Steven
Object Type: Report
System: The UNT Digital Library