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Information Security: Continued Efforts Needed to Sustain Progress in Implementing Statutory Requirements (open access)

Information Security: Continued Efforts Needed to Sustain Progress in Implementing Statutory Requirements

Testimony issued by the General Accounting Office with an abstract that begins "For many years, GAO has reported on the widespread negative impact of poor information security within federal agencies and has identified it as a governmentwide high-risk issue since 1997. Legislation designed to improve information security was enacted in October 2000. It was strengthened in December 2002 by new legislation, the Federal Information Security Management Act of 2002 (FISMA), which incorporated important new requirements. This testimony discusses (1) the Office of Management and Budget's (OMB) recent report to the Congress required by FISMA on the government's overall information security posture, (2) the reported status of efforts by 24 of the largest agencies to implement federal information security requirements, (3) opportunities for improving the usefulness of performance measurement data, and (4) progress by the National Institute of Standards and Technology (NIST) to develop related standards and guidance."
Date: March 16, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Homeland Security: Risk Communication Principles May Assist in Refinement of the Homeland Security Advisory System (open access)

Homeland Security: Risk Communication Principles May Assist in Refinement of the Homeland Security Advisory System

Testimony issued by the General Accounting Office with an abstract that begins "Established in March 2002, the Homeland Security Advisory System was designed to disseminate information regarding the risk of terrorist acts to federal, state, and local government agencies, private industry, and the public. However, this system generated questions among these entities regarding whether they were receiving the necessary information to respond appropriately to heightened alerts. GAO obtained information on how the Homeland Security Advisory System operates, including the process used to notify federal, state, and local government agencies, private industry, and the public of changes in the threat level. GAO also reviewed literature on risk communication to identify principles and factors to be considered when determining when, what, and how information should be disseminated about threat level changes. Additionally, GAO researched what type of information had been provided to federal, state, and local agencies, private industry, and the public regarding terrorist threats. GAO also identified protective measures that were suggested for these entities to implement during code-orange alerts. Last, GAO identified additional information requested by recipients of threat information."
Date: March 16, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
[Minutes: Intelligence Joint Cross-Service Group, March 16, 2004] (open access)

[Minutes: Intelligence Joint Cross-Service Group, March 16, 2004]

BRAC 2005 Intelligence Joint Cross-Service Group Meeting Minutes of March 16, 2004. The document is redacted and includes the Military Value Report brief (PowerPoint slides).
Date: March 16, 2004
Creator: United States. Department of Defense.
Object Type: Text
System: The UNT Digital Library
Design and testing of a control strategy for a large naturallyventilated office building (open access)

Design and testing of a control strategy for a large naturallyventilated office building

The design for the new Federal Building for San Franciscoincludes an office tower that is to be naturally ventilated. Each flooris designed to be cross-ventilated, through upper windows that arecontrolled by the building management system (BMS). Users have controlover lower windows, which can be as much as 50 percent of the totalopenable area. There are significant differences in the performance andthe control of the windward and leeward sides of the building, andseparate monitoring and control strategies are determined for each side.The performance and control of the building has been designed and testedusing a modified version of EnergyPlus. Results from studies withEnergyPlus and CFD are used in designing the control strategy. EnergyPluswas extended to model a simplified version of the airflow patterndetermined using CFD. Wind-driven cross-ventilation produces a main jetthrough the upper openings of the building, across the ceiling from thewindward to the leeward side. Below this jet, the occupied regions aresubject to a recirculating air flow. Results show that temperatureswithin the building are predicted to be satisfactory, provided a suitablecontrol strategy is implemented uses night cooling in periods of hotweather. The control strategy has 10 window opening modes. EnergyPlus wasextended to simulate the effects of these modes, and to assess …
Date: March 16, 2004
Creator: Carrilho da Graca, Guilherme; Linden, Paul F. & Haves, Philip
Object Type: Article
System: The UNT Digital Library
Foreign Assistance Authorization Act, FY2005 (open access)

Foreign Assistance Authorization Act, FY2005

None
Date: March 16, 2004
Creator: Nowels, Larry
Object Type: Report
System: The UNT Digital Library
Warped Supersymmetric Unification with Non-Unified Superparticle Spectrum (open access)

Warped Supersymmetric Unification with Non-Unified Superparticle Spectrum

We present a new supersymmetric extension of the standard model. The model is constructed in warped space, with a unified bulk symmetry broken by boundary conditions on both the Planck and TeV branes. In the supersymmetric limit, the massless spectrum contains exotic colored particles along with the particle content of the minimal supersymmetric standard model (MSSM). Nevertheless, the model still reproduces the MSSM prediction for gauge coupling unification and does not suffer from a proton decay problem. The exotic states acquire masses from supersymmetry breaking, making the model completely viable, but thereis still the possibility that these states will be detected at the LHC. The lightest of these states is most likely A_5^XY, the fifth component of the gauge field associated with the broken unified symmetry. Because supersymmetry is broken on the SU(5)-violating TeV brane, the gaugino masses generated at the TeV scale are completely independent of one another. We explore some of the unusual features that the superparticle spectrum might have as a consequence.
Date: March 16, 2004
Creator: Nomura, Yasunori; Tucker-Smith, David & Tweedie, Brock
Object Type: Article
System: The UNT Digital Library
Matter Unification in Warped Supersymmetric SO(10) (open access)

Matter Unification in Warped Supersymmetric SO(10)

We construct models of warped unification with a bulk SO(10) gauge symmetry and boundary conditions that preserve the SU(4)_C x SU(2)_L x SU(2)_R Pati-Salam gauge group (422). In the dual 4D description, these models are 422 gauge theories in which the apparent unification of gauge couplings in the minimal supersymmetric standard model is explained as a consequence of strong coupling in the ultraviolet. The weakness of the gauge couplings at low energies is ensured in this 4D picture by asymptotically non-free contributions from the conformal sector, which are universal due to an approximate SO(10) global symmetry. The 422 gauge symmetry is broken to the standard model group by a simple set of Higgs fields. An advantage of this setup relative to SU(5) models of warped unification is that matter is automatically required to fill out representations of 422, providing an elegant understanding of the quantum numbers of the standard-model quarks and leptons. The models also naturally incorporate the see-saw mechanism for neutrino masses and bottom-tau unification. Finally, they predict a rich spectrum of exotic particles near the TeV scale, including states with different quantum numbers than those that appear in SU(5) models.
Date: March 16, 2004
Creator: Nomura, Yasunori & Tucker-Smith, David
Object Type: Article
System: The UNT Digital Library
21st Century Community Learning Centers in P.L. 107-110: Background and Funding (open access)

21st Century Community Learning Centers in P.L. 107-110: Background and Funding

This report summarizes the major provisions of the reauthorized 21st Century Community Learning Centers (21st CCLC) program. It includes sections on fundings, national reservations, formula grants to states, competitive local grants, history, program effectiveness, and relevant legislation in the 107th Congress.
Date: March 16, 2004
Creator: McCallion, Gail
Object Type: Report
System: The UNT Digital Library
Enhanced vibrations at surfaces with back-bonds nearly parallel to the surface (open access)

Enhanced vibrations at surfaces with back-bonds nearly parallel to the surface

It has been discovered that several very different surfaces exhibit a common property: unusually large vibration amplitudes of the outermost atoms, well beyond the enhancement normally expected at typical clean surfaces. These special surfaces are: ice H2O(0001), alpha-Al2O3(0001), alpha-Ga(010) and Si(111)-(2x1). The root-mean-square vibration amplitudes in these surfaces are at least double the bulk values. The common cause that may explain these vibration amplitudes is that the surface atoms (or molecules in the case of ice) only have back-bonds that are nearly parallel to the surface. In this geometry, vibrations, especially perpendicular to the surface, involve primarily bond bending rather than bond stretching/compression: since bond bending is relatively soft, the corresponding vibration modes can have larger amplitudes. It is suggested that theory examine and confirm this cause of enhanced surface vibration amplitudes, and explore its implication for other phenomena such as adsorption and catalysis.
Date: March 16, 2004
Creator: Van Hove, M.A.
Object Type: Article
System: The UNT Digital Library
Applying synchrotron phase measurement to the estimation of maximum beam intensity in the Fermilab Booster (open access)

Applying synchrotron phase measurement to the estimation of maximum beam intensity in the Fermilab Booster

It is important to have experimental methods to estimate the maximum beam intensity for the Fermilab Booster as objective input into long term program commitments. An important existing limit is set by the available rf power. This limit is difficult to set a priori, because the real longitudinal impedance is not well known. The synchrotron phase at transition crossing was measured using both the mountain range plot and the direct phase measurement of the RF accelerating voltage relative to the beam, and results were consistent. They were applied to predict 6 x 10{sup 12} maximum Booster beam intensity with present running conditions.
Date: March 16, 2004
Creator: Yang, Xi & MacLachlan, James
Object Type: Report
System: The UNT Digital Library
SOFC INTERCONNECT DEVELOPMENT (open access)

SOFC INTERCONNECT DEVELOPMENT

An interconnect for an SOFC stack is used to connect fuel cells into a stack. SOFC stacks are expected to run for 40,000 hours and 10 thermal cycles for the stationary application and 10,000 hours and 7000 thermal cycles for the transportation application. The interconnect of a stack must be economical and robust enough to survive the SOFC stack operation temperature of 750 C and must maintain the electrical connection to the fuel cells throughout the lifetime and under thermal cycling conditions. Ferritic and austenitic stainless steels, and nickel-based superalloys were investigated as possible interconnect materials for solid oxide fuel cell (SOFC) stacks. The alloys were thermally cycled in air and in a wet nitrogen-argon-hydrogen (N2-Ar-H2-H2O) atmosphere. Thermogravimetry was used to determine the parabolic oxidation rate constants of the alloys in both atmospheres. The area-specific resistance of the oxide scale and metal substrates were measured using a two-probe technique with platinum contacts. The study identifies two new interconnect designs which can be used with both bonded and compressive stack sealing mechanisms. The new interconnect designs offer a solution to chromium vaporization, which can lead to degradation of some (chromium-sensitive) SOFC cathodes.
Date: March 16, 2004
Creator: England, Diane M.
Object Type: Report
System: The UNT Digital Library
Deep Vs Profiling Along the Top of Yucca Mountain Using a Vibroseis Source and Surface Waves (open access)

Deep Vs Profiling Along the Top of Yucca Mountain Using a Vibroseis Source and Surface Waves

Yucca Mountain, Nevada, was approved as the site for development of the geologic repository for high-level radioactive waste and spent nuclear fuel in the United States. The U.S. Department of Energy has been conducting studies to characterize the site and assess its future performance as a geologic repository. As part of these studies, a program of deep seismic profiling, to depths of 200 m, was conducted along the top of Yucca Mountain to evaluate the shear-wave velocity (V{sub s}) structure of the repository block. The resulting V{sub s} data were used as input into the development of ground motions for the preclosure seismic design of the repository and for postclosure performance assessment. The noninvasive spectral-analysis-of-surface-waves (SASW) method was employed in the deep profiling. Field measurements involved the use of a modified Vibroseis as the seismic source. The modifications allowed the Vibroseis to be controlled by a signal analyzer so that slow frequency sweeps could be performed while simultaneous narrow-band filtering was performed on the receiver outputs. This process optimized input energy from the source and signal analysis of the receiver outputs. Six deep V{sub s} profiles and five intermediate-depth (about 100 m) profiles were performed along the top of Yucca …
Date: March 16, 2004
Creator: Stokoe, K.; Rosenblad, B.; Wong, I.; Bay, J.; Thomas, P. & Silva, W.
Object Type: Article
System: The UNT Digital Library
YbiV from E. coli K12 is a HAD phosphatase (open access)

YbiV from E. coli K12 is a HAD phosphatase

The protein YbiV from Escherichia coli K12 MG1655 is a hypothetical protein with sequence homology to the haloacid dehalogenase (HAD) superfamily of proteins. Although numerous members of this family have been identified, the functions of few are known. Using the crystal structure, sequence analysis, and biochemical assays, we have characterized ybiV as a HAD phosphatase. The crystal structure of YbiV reveals a two domain protein, one with the characteristic HAD hydrolase fold, the other an inserted a/b fold. In an effort to understand the mechanism we also solved and report the structures of YbiV in complex with beryllofluoride (BeF3-) and aluminum trifluoride (AlF3) which have been shown to mimic the phosphorylated intermediate and transition state for hydrolysis, respectively, in analogy to other HAD phosphatases. Analysis of the structures reveals the substrate binding cavity, which is hydrophilic in nature. Both structure and sequence homology indicate ybiV may be a sugar phosphatase, which is supported by biochemical assays which measured the release of free phosphate on a number of sugar-like substrates. We also investigated available genomic and functional data in an effort to determine the physiological substrate.
Date: March 16, 2004
Creator: Roberts, Anne; Lee, Seok-Yong; McCullagh, Emma; Silversmith, Ruth E. & Wemmer, David E.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 82, No. 105, Ed. 1 Tuesday, March 16, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 82, No. 105, Ed. 1 Tuesday, March 16, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 16, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Parliamentary Reference Sources: House of Representatives (open access)

Parliamentary Reference Sources: House of Representatives

This report discusses the availability and format of three types of parliamentary reference materials: official sources such as the House Rules and Manual and the published precedents; publications of committees and offices of the House; and documents prepared by House party and leadership organizations. It also reviews some principles of House parliamentary procedure that are important to consider when using information from parliamentary reference sources.
Date: March 16, 2004
Creator: Carr, Thomas P.
Object Type: Report
System: The UNT Digital Library
The effect of a short wavelength mode on the evolution of a long wavelength perturbation driven by a strong blast wave (open access)

The effect of a short wavelength mode on the evolution of a long wavelength perturbation driven by a strong blast wave

Shock-accelerated material interfaces are potentially unstable to both the Richtmyer-Meshkov and Rayleigh-Taylor instabilities. Shear that develops along with these instabilities in turn drives the Kelvin-Helmholtz instability. When driven by strong shocks, the evolution and interaction of these instabilities is further complicated by compressibility effects. In this paper, we present a computational study of the formation of jets at strongly driven hydrodynamically unstable interfaces, and the interaction of these jets with one another and with developing spikes and bubbles. This provides a nonlinear spike-spike and spike-bubble interaction mechanism that can have a significant impact on the large-scale characteristics of the mixing layer. These interactions result in sensitivity to the initial perturbation spectrum, including the relative phases of the various modes, that persists long into the nonlinear phase of instability evolution. We describe implications for instability growth rates, the bubble merger process, and the degree of mix in the layer. Finally, we consider results from relevant deceleration RT experiments, performed on OMEGA, to demonstrate some of these effects.
Date: March 16, 2004
Creator: Miles, A. R.; Edwards, M.; Blue, B.; Hansen, J. F.; Robey, H. F.; Drake, R. P. et al.
Object Type: Article
System: The UNT Digital Library
Leaking Underground Storage Tanks: Program Status and Issues (open access)

Leaking Underground Storage Tanks: Program Status and Issues

None
Date: March 16, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fermion Monte Carlo Calculations on Liquid-3He (open access)

Fermion Monte Carlo Calculations on Liquid-3He

Methods and results for calculations of the ground state energy of the bulk system of {sup 3}He atoms are discussed. Results are encouraging: they believe that they demonstrate that their methods offer a solution of the ''fermion sign problem'' and the possibility of direct computation of many-fermion systems with no uncontrolled approximations. Nevertheless, the method is still rather inefficient compared with variational or fixed-node approximate methods. There appears to be a significant populations size effect. The situation is improved by the inclusion of ''Second Stage Importance Sampling'' and of ''Acceptance/Rejection'' adapted to their needs.
Date: March 16, 2004
Creator: Kalos, M H; Colletti, L & Pederiva, F
Object Type: Report
System: The UNT Digital Library
Comparison of two up-scaling methods in poroelasticity and its generalizations (open access)

Comparison of two up-scaling methods in poroelasticity and its generalizations

Two methods of up-scaling coupled equations at the microscale to equations valid at the mesoscale and/or macroscale for fluid-saturated and partially saturated porous media are discussed, compared, and contrasted. The two methods are: (1) two-scale and multiscale homogenization, and (2) volume averaging. Both these methods have advantages for some applications and disadvantages for others. For example, homogenization methods can give formulas for coefficients in the up-scaled equations, whereas volume averaging methods give the form of the up-scaled equations but generally must be supplemented with physical arguments and/or data in order to determine the coefficients. Homogenization theory requires a great deal of mathematical insight from the user in order to choose appropriate scalings for use in the resulting power-law expansions, while volume averaging requires more physical insight to motivate the steps needed to find coefficients. Homogenization often is performed on periodic models, while volume averaging does not require any assumption of periodicity and can therefore be related very directly to laboratory and/or field measurements. Validity of the homogenization process is often limited to specific ranges of frequency - in order to justify the scaling hypotheses that must be made - and therefore cannot be used easily over wide ranges of frequency. …
Date: March 16, 2004
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
Focusing Hard X-rays at Current and Future Light Sources for Microscopy and High-Power Applications (open access)

Focusing Hard X-rays at Current and Future Light Sources for Microscopy and High-Power Applications

The field of x-ray optics struggles to develop optical systems with the versatility and sophistication of their visible light counterparts. The advent of fourth-generation light sources will make the struggle even more difficult. Fourth-generation light sources include laser/plasma sources, x-ray Free Electron Lasers (FEL), inverse Compton scattering sources, and the National Ignition Facility. LCLS, (Linac Coherent Light Source), and its European cousin, will be the first of the x-ray FELs. The LCLS, to be built at the Stanford Linear Accelerator Center (SLAC), takes advantage of the existing SLAC linear accelerator to send intense, low emittance electron bunches through a 100 m long undulator structure. Through a process called SASE (Self Amplification of Spontaneous Emission) the electrons interact with the radiation fields they produce while in the undulator causing them to collect into micro bunches that emit coherent light. In the case of the LCLS the coherent radiation will have a wavelength in the x-ray regime, and will be tunable from 1.5 to 15 {angstrom}. The LCLS will deliver x-rays in individual coherent packages lasting < 300 fs, making the LCLS a very important source for studying short time phenomenon and for performing high-resolution x-ray structural analysis of molecular sized systems. …
Date: March 16, 2004
Creator: Bionta, R M
Object Type: Report
System: The UNT Digital Library
Agricultural Biotechnology: The U.S.-EU Dispute (open access)

Agricultural Biotechnology: The U.S.-EU Dispute

This report focuses on a conflict between the European Union (EU) and the United States, Canada, and Argentina. The United States suggests that the European Union's moratorium costs the U.S. 300 million dollars in exports to the EU annually. Moreover, the report highlights other concerns the U.S. has with the EU's biotechnology policies.
Date: March 16, 2004
Creator: Becker, Geoffrey S. & Hanrahan, Charles E.
Object Type: Report
System: The UNT Digital Library
Parliamentary Reference Sources: Senate (open access)

Parliamentary Reference Sources: Senate

None
Date: March 16, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Trends in U.S. Agricultural Export Credit Guarantee Programs and P.L. 480, Title I, FY1992-FY2002 (open access)

Trends in U.S. Agricultural Export Credit Guarantee Programs and P.L. 480, Title I, FY1992-FY2002

None
Date: March 16, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Thermodynamic Properties of Quinoxaline-1,4-Dioxide Derivatives: A Combined Experimental and Computational Study (open access)

Thermodynamic Properties of Quinoxaline-1,4-Dioxide Derivatives: A Combined Experimental and Computational Study

Article on thermodynamic properties of quinoxaline-1,4-dioxide derivatives and a combined experimental and computational study.
Date: March 16, 2004
Creator: Silva, Maria D. M. C. Ribeiro da; Gomes, José R. B.; Gonçalves, Jorge M.; Sousa, Emanuel A.; Pandey, Siddharth & Acree, William E. (William Eugene)
Object Type: Article
System: The UNT Digital Library