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Critical Infrastructure Protection: Update to National Infrastructure Protection Plan Includes Increased Emphasis on Risk Management and Resilience (open access)

Critical Infrastructure Protection: Update to National Infrastructure Protection Plan Includes Increased Emphasis on Risk Management and Resilience

A letter report issued by the Government Accountability Office with an abstract that begins "According to the Department of Homeland Security (DHS), there are thousands of facilities in the United States that if destroyed by a disaster could cause casualties, economic losses, or disruptions to national security. The Homeland Security Act of 2002 gave DHS responsibility for leading and coordinating the nation's effort to protect critical infrastructure and key resources (CIKR). Homeland Security Presidential Directive 7 (HSPD-7) defined responsibilities for DHS and certain federal agencies--known as sector-specific agencies (SSAs)--that represent 18 industry sectors, such as energy. In accordance with the Homeland Security Act and HSPD-7, DHS issued the National Infrastructure Protection Plan (NIPP) in June 2006 to provide the approach for integrating the nation's CIKR. GAO was asked to study DHS's January 2009 revisions to the NIPP in light of a debate over whether DHS has emphasized protection--to deter threats, mitigate vulnerabilities, or minimize the consequences of disasters---rather than resilience---to resist, absorb, or successfully adapt, respond to, or recover from disasters. This report discusses (1) how the 2009 NIPP changed compared to the 2006 NIPP and (2) how DHS and SSAs addressed resiliency as part of their planning efforts. GAO …
Date: March 5, 2010
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Recovery Act: California's Use of Funds and Efforts to Ensure Accountability (open access)

Recovery Act: California's Use of Funds and Efforts to Ensure Accountability

Testimony issued by the Government Accountability Office with an abstract that begins "The American Recovery and Reinvestment Act of 2009 (Recovery Act) specifies several roles for GAO, including conducting bimonthly reviews of selected states' and localities' use of funds made available under the act. This testimony is based on GAO's bimonthly work in California, where the Recovery Act provided more than $85 billion--or about 10 percent of the funds available nationally--for program funding and tax relief. This testimony provides a general overview of: (1) California's use of Recovery Act funds for selected programs, (2) the approaches taken by California agencies to ensure accountability for Recovery Act funds, and (3) the impacts of these funds. This testimony focuses on selected programs that GAO has covered in previous work including the use of Recovery Act funds by the state and two localities' --City of Los Angeles and County of Sacramento, Highway Infrastructure Investment, and the Weatherization Assistance Program. GAO also updated information on three education programs with significant Recovery Act funds being disbursed--the State Fiscal Stabilization Fund (SFSF), and Recovery Act funds for Title I, Part A, of the Elementary and Secondary Education Act of 1965 (ESEA), as amended, and Part B …
Date: March 5, 2010
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Cybersecurity: Progress Made but Challenges Remain in Defining and Coordinating the Comprehensive National Initiative (open access)

Cybersecurity: Progress Made but Challenges Remain in Defining and Coordinating the Comprehensive National Initiative

A letter report issued by the Government Accountability Office with an abstract that begins "In response to the ongoing threats to federal systems and operations posed by cyber attacks, President Bush established the Comprehensive National Cybersecurity Initiative (CNCI) in 2008. This initiative consists of a set of projects aimed at reducing vulnerabilities, protecting against intrusions, and anticipating future threats. GAO was asked to determine (1) what actions have been taken to develop interagency mechanisms to plan and coordinate CNCI activities and (2) what challenges CNCI faces in achieving its objectives related to securing federal information systems. To do this, GAO reviewed CNCI plans, policies, and other documentation and interviewed officials at the Office of Management and Budget (OMB), Department of Homeland Security, and the Office of the Director of National Intelligence (ODNI), among other agencies. GAO also reviewed studies examining aspects of federal cybersecurity and interviewed recognized cybersecurity experts."
Date: March 5, 2010
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Energy Star Program: Covert Testing Shows the Energy Star Program Certification Process Is Vulnerable to Fraud and Abuse (open access)

Energy Star Program: Covert Testing Shows the Energy Star Program Certification Process Is Vulnerable to Fraud and Abuse

A letter report issued by the Government Accountability Office with an abstract that begins "American consumers, businesses, and federal agencies rely on the Energy Star program to identify products that decrease greenhouse emissions and lower energy costs. In addition, the federal government and various states offer tax credits and other incentives to encourage the use of energy-efficient products including Energy Star products. Specifically, approximately $300 million from the American Recovery and Reinvestment Act will be used for state rebate programs on energy-efficient products. The Energy Star program, which began in 1992, is overseen jointly by the U.S. Department of Energy (DOE) and the U.S. Environmental Protection Agency (EPA). Given the millions of dollars allocated to encourage use of Energy Star products and concerns that the Energy Star program is vulnerable to fraud and abuse, GAO was asked to conduct proactive testing to (1) obtain Energy Star partnership status for bogus companies and (2) submit fictitious products for Energy Star certification. To perform this investigation, GAO used four bogus manufacturing firms and fictitious individuals to apply for Energy Star partnership and submitted 20 fictitious products with fake energy-savings claims for Energy Star certification. GAO also reviewed program documents and interviewed agency …
Date: March 5, 2010
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 58, Ed. 1 Friday, March 5, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 58, Ed. 1 Friday, March 5, 2010

Free weekly newspaper that includes business and classified advertising.
Date: March 5, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Houston, Tex.), Vol. 41, No. 60, Ed. 1 Friday, March 5, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 60, Ed. 1 Friday, March 5, 2010

Free weekly newspaper that includes business and classified advertising.
Date: March 5, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Optimist (Abilene, Tex.), Vol. 98, No. 42, Ed. 1 Friday, March 5, 2010 (open access)

The Optimist (Abilene, Tex.), Vol. 98, No. 42, Ed. 1 Friday, March 5, 2010

Bi-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: March 5, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Ranger (San Antonio, Tex.), Vol. 84, No. 17, Ed. 1 Friday, March 5, 2010 (open access)

The Ranger (San Antonio, Tex.), Vol. 84, No. 17, Ed. 1 Friday, March 5, 2010

Weekly student newspaper from San Antonio College in San Antonio, Texas that includes campus news along with advertising.
Date: March 5, 2010
Creator: San Antonio College
Object Type: Newspaper
System: The Portal to Texas History
Texas Register, Volume 35, Number 10, Pages 1831-2092, March 5, 2010 (open access)

Texas Register, Volume 35, Number 10, Pages 1831-2092, March 5, 2010

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: March 5, 2010
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 95, No. 28, Ed. 1 Friday, March 5, 2010 (open access)

North Texas Daily (Denton, Tex.), Vol. 95, No. 28, Ed. 1 Friday, March 5, 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 5, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Dallas Voice (Dallas, Tex.), Vol. 26, No. 42, Ed. 1 Friday, March 5, 2010 (open access)

Dallas Voice (Dallas, Tex.), Vol. 26, No. 42, Ed. 1 Friday, March 5, 2010

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: March 5, 2010
Creator: Nash, Tammye
Object Type: Newspaper
System: The UNT Digital Library
Visualization and Analysis-Oriented Reconstruction of Material Interfaces (open access)

Visualization and Analysis-Oriented Reconstruction of Material Interfaces

Reconstructing boundaries along material interfaces from volume fractions is a difficult problem, especially because the under-resolved nature of the input data allows for many correct interpretations. Worse, algorithms widely accepted as appropriate for simulation are inappropriate for visualization. In this paper, we describe a new algorithm that is specifically intended for reconstructing material interfaces for visualization and analysis requirements. The algorithm performs well with respect to memory footprint and execution time, has desirable properties in various accuracy metrics, and also produces smooth surfaces with few artifacts, even when faced with more than two materials per cell.
Date: March 5, 2010
Creator: Childs, Henry R.
Object Type: Article
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 59, Ed. 1 Friday, March 5, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 59, Ed. 1 Friday, March 5, 2010

Free weekly newspaper that includes business and classified advertising.
Date: March 5, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Mechanisms underlying cellular responses of cells from haemopoietic tissue to low dose/low LET radiation (open access)

Mechanisms underlying cellular responses of cells from haemopoietic tissue to low dose/low LET radiation

To accurately define the risks associated with human exposure to relevant environmental doses of low LET ionizing radiation, it is necessary to completely understand the biological effects at very low doses (i.e., less than 0.1 Gy), including the lowest possible dose, that of a single electron track traversal. At such low doses, a range of studies have shown responses in biological systems which are not related to the direct interaction of radiation tracks with DNA. The role of these “non-targeted” responses in critical tissues is poorly understood and little is known regarding the underlying mechanisms. Although critical for dosimetry and risk assessment, the role of individual genetic susceptibility in radiation risk is not satisfactorily defined at present. The aim of the proposed grant is to critically evaluate radiation-induced genomic instability and bystander responses in key stem cell populations from haemopoietic tissue. Using stem cells from two mouse strains (CBA/H and C57BL/6J) known to differ in their susceptibility to radiation effects, we plan to carefully dissect the role of genetic predisposition on two non-targeted radiation responses in these models; the bystander effect and genomic instability, which we believe are closely related. We will specifically focus on the effects of low doses …
Date: March 5, 2010
Creator: Kadhim, Munira A
Object Type: Report
System: The UNT Digital Library
High-Power Electrostatic Discharges in PETN: Threshold and Scaling Experiments (open access)

High-Power Electrostatic Discharges in PETN: Threshold and Scaling Experiments

There is a considerable set of data establishing the safety of PETN-based detonators that are insulted by electrostatic discharge (ESD) from a human body. However, the subject of ESD safety has garnered renewed interest because of the sparse data on high-power, low-impedance discharges that result when the source is a metallic object such as a tool. Experiments on as-built components, using pin-to-cap fault circuits through PETN-based detonators, showed significant evidence of a power dependence but with a very broad energy threshold and some uncertainty in the breakdown path. We have performed a series of experiments using a well-defined arc discharge path and a well-characterized source that is capable of independent variation of energy and power. Studies include threshold variation with power, arc length, powder surface area, and surface vs. bulk discharge paths. We find that an energy threshold variation with power does not appear to exist in the tested range of fractions to tens of MW, and that there are many subtleties to proper energy and power bookkeeping. We also present some test results for PBX 9407.
Date: March 5, 2010
Creator: Liou, W.; McCarrick, J. F.; Hodgin, R. L. & Phillips, D. F.
Object Type: Article
System: The UNT Digital Library
Propagation of Reactions in Thermally-damaged PBX-9501 (open access)

Propagation of Reactions in Thermally-damaged PBX-9501

A thermally-initiated explosion in PBX-9501 (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) is observed in situ by flash x-ray imaging, and modeled with the LLNL multi-physics arbitrary-Lagrangian-Eulerian code ALE3D. The containment vessel deformation provides a useful estimate of the reaction pressure at the time of the explosion, which we calculate to be in the range 0.8-1.4 GPa. Closely-coupled ALE3D simulations of these experiments, utilizing the multi-phase convective burn model, provide detailed predictions of the reacted mass fraction and deflagration front acceleration. During the preinitiation heating phase of these experiments, the solid HMX portion of the PBX-9501 undergoes a {beta}-phase to {delta}-phase transition which damages the explosive and induces porosity. The multi-phase convective burn model results demonstrate that damaged particle size and pressure are critical for predicting reaction speed and violence. In the model, energetic parameters are taken from LLNL's thermochemical-kinetics code Cheetah and burn rate parameters from Son et al. (2000). Model predictions of an accelerating deflagration front are in qualitative agreement with the experimental images assuming a mode particle diameter in the range 300-400 {micro}m. There is uncertainty in the initial porosity caused by thermal damage of PBX-9501 and, thus, the effective surface area for burning. To better understand these structures, we employ x-ray computed …
Date: March 5, 2010
Creator: Tringe, J W; Glascoe, E A; Kercher, J R; Willey, T M; Springer, H K; Greenwood, D W et al.
Object Type: Article
System: The UNT Digital Library
Thermal Degradation Studies of Polyurethane/POSS Nanohybrid Elastomers (open access)

Thermal Degradation Studies of Polyurethane/POSS Nanohybrid Elastomers

Reported here is the synthesis of a series of Polyurethane/POSS nanohybrid elastomers, the characterization of their thermal stability and degradation behavior at elevated temperatures using a combination of Thermal Gravimetric Analysis (TGA) and Thermal Volatilization Analysis (TVA). A series of PU elastomers systems have been formulated incorporating varying levels of 1,2-propanediol-heptaisobutyl-POSS (PHIPOSS) as a chain extender unit, replacing butane diol. The bulk thermal stability of the nanohybrid systems has been characterized using TGA. Results indicate that covalent incorporation of POSS into the PU elastomer network increase the non-oxidative thermal stability of the systems. TVA analysis of the thermal degradation of the POSS/PU hybrid elastomers have demonstrated that the hybrid systems are indeed more thermally stable when compared to the unmodified PU matrix; evolving significantly reduced levels of volatile degradation products and exhibiting a {approx}30 C increase in onset degradation temperature. Furthermore, characterization of the distribution of degradation products from both unmodified and hybrid systems indicate that the inclusion of POSS in the PU network is directly influencing the degradation pathways of both the soft and hard block components of the elastomers: The POSS/PU hybrid systems show reduced levels of CO, CO2, water and increased levels of THF as products of …
Date: March 5, 2010
Creator: Lewicki, J P; Pielichowski, K; TremblotDeLaCroix, P; Janowski, B; Todd, D & Liggat, J J
Object Type: Article
System: The UNT Digital Library
Pressure-induced isostructural transition in PdN2 (open access)

Pressure-induced isostructural transition in PdN2

We show that a synthesized Pd-N compound crystallize into the pyrite structure by comparison of experimental and calculated Raman intensities. The decreasing Raman intensities with decreasing pressure is explained by a closing of the fundamental band gap. We further discuss the experimental decomposition of this compound at 11 GPa in terms of an isostructural transition within the pyrite structure.
Date: March 5, 2010
Creator: Aberg, D; Erhart, P; Crowhurst, J; Zaug, J M; Goncharov, A F & Sadigh, B
Object Type: Article
System: The UNT Digital Library
Towards the understanding of PETN initiation by a fast, high power arc source (open access)

Towards the understanding of PETN initiation by a fast, high power arc source

We present a thorough characterization of a capacitor driven arc source that can deliver up to 200 mJ of energy to the arc and high explosive in a well-controlled, repeatable manner on the hundreds of nanoseconds time-scale. Our ultimate purpose is to create a platform to study high explosive kinetics under extreme conditions of high-temperature. In the current paper, we characterize the behavior of our arc source by electrical discharge over a thin PETN film. Temperature and density are determined by time-resolved atomic emission spectroscopy on the nano- to microsecond time scale along with fast photographic imaging to capture time-resolved images of the expanding plasma. We also discuss preliminary simulations of arc plasma using a 1-D hydrodynamic model. Comparisons of these simulations with experimental data are presented. Ultimately our goal is to create a platform that will generate conditions of high temperature in order to study high explosive kinetics. We believe that our arc source platform can be further combined with a time-resolved vibrational spectroscopy (e.g. IR or Raman) to study chemical kinetics under extreme conditions. High temperature conditions may access novel reactive pathways that are different from either shock or slower thermal processes that are substantially lower in temperature.
Date: March 5, 2010
Creator: Grant, C D; Tang, V; Glascoe, E A & McCarrick, J F
Object Type: Article
System: The UNT Digital Library
Comparison of the Growth of Pore and Shear Band Driven Detonations (open access)

Comparison of the Growth of Pore and Shear Band Driven Detonations

The authors examine the effect of ignition site topology on the rate of reaction of a detonating material. The hot plane, hot line, and hot finite patch topologies are added to previous work on hot spot ignition. The hot plane and hot patch ignition forms would arise from ignition due to shear banding, and the hot line ignition form is shown to complete the topological set. The limiting behavior of instantaneous ignition is considered and used to construct simple reaction rate vs. extent of reaction forms. they fit simple form factor reaction rates, as might be available in most hydro codes with reactive flow modes, to the simple topologies. The difference between the rate vs. extent forms are examined with the objective that one should be able to use this information to distinguish between the different topological ignition forms.
Date: March 5, 2010
Creator: Nichols, A. L.
Object Type: Article
System: The UNT Digital Library
Improved Modeling and Understanding of Diffusion-Media Wettability on Polymer-Electrolyte-Fuel-Cell Performance (open access)

Improved Modeling and Understanding of Diffusion-Media Wettability on Polymer-Electrolyte-Fuel-Cell Performance

A macroscopic-modeling methodology to account for the chemical and structural properties of fuel-cell diffusion media is developed. A previous model is updated to include for the first time the use of experimentally measured capillary pressure -- saturation relationships through the introduction of a Gaussian contact-angle distribution into the property equations. The updated model is used to simulate various limiting-case scenarios of water and gas transport in fuel-cell diffusion media. Analysis of these results demonstrate that interfacial conditions are more important than bulk transport in these layers, where the associated mass-transfer resistance is the result of higher capillary pressures at the boundaries and the steepness of the capillary pressure -- saturation relationship. The model is also used to examine the impact of a microporous layer, showing that it dominates the response of the overall diffusion medium. In addition, its primary mass-transfer-related effect is suggested to be limiting the water-injection sites into the more porous gas-diffusion layer.
Date: March 5, 2010
Creator: Weber, Adam
Object Type: Article
System: The UNT Digital Library
Fracture Induced Sub-Band Absorption as a Precursor to Optical Damage on Fused Silica Surfaces (open access)

Fracture Induced Sub-Band Absorption as a Precursor to Optical Damage on Fused Silica Surfaces

The optical damage threshold of indentation induced flaws on fused silica surfaces was explored. Mechanical flaws were characterized by laser damaged testing, SEM, optical, and photoluminescence microscopy. Localized polishing, chemical etching, and the control of indentation morphology were used to isolate the structural features which limit optical damage. A thin defect layer on fracture surfaces, including those smaller than the wavelength of visible light, was found to be the dominant source of laser damage initiation during illumination with 355nm, 3ns laser pulses. Little evidence was found that either displaced or densified material or fluence intensification plays a significant role in optical damage at fluences >35J/cm{sup 2}. Elimination of the defect layer was shown to increase the overall damage performance of fused silica optics.
Date: March 5, 2010
Creator: Miller, P E; Bude, J D; Suratwala, T I; Shen, N; Laurence, T A; Steele, W A et al.
Object Type: Article
System: The UNT Digital Library
Brazil-U.S. Relations (open access)

Brazil-U.S. Relations

This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: March 5, 2010
Creator: Meyer, Peter J.
Object Type: Report
System: The UNT Digital Library
Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power (open access)

Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power

This report discusses motivating factors underlying the resurgent interest in nuclear power, the nuclear power industry's current state of affairs, and the interdependence of the various stages of the nuclear fuel cycle. A number of proposals have been offered that are aimed at limiting direct participation in the global nuclear fuel industry by assuring access to nuclear fuel supplies.
Date: March 5, 2010
Creator: Nikitin, Mary Beth; Andrews, Anthony & Holt, Mark
Object Type: Report
System: The UNT Digital Library