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Federal-Aid Highways: Increased Reliance on Contractors Can Pose Oversight Challenges for Federal and State Officials

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Pressure on state and local governments to deliver highway projects and services, and limits on the ability of state departments of transportation (state DOT) to increase staff levels have led those departments to contract out a variety of highway activities to the private sector. As requested, this report addresses (1) recent trends in the contracting of state highway activities, (2) factors that influ… more
Date: January 8, 2008
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Information Security: IRS Needs to Address Pervasive Weaknesses

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Internal Revenue Service (IRS) relies extensively on computerized systems to carry out its demanding responsibilities to collect taxes (about $2.7 trillion in fiscal year 2007), process tax returns, and enforce the nation's tax laws. Effective information security controls are essential to ensuring that financial and taxpayer information is adequately protected from inadvertent or deliberate misuse,… more
Date: January 8, 2008
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Supplemental Security Income (SSI): A Fact Sheet

Description: The Supplemental Security Income (SSI) program, Title XVI of the Social Security Act, was enacted in 1972 and implemented in 1974 to assure a minimum cash income to all aged, blind, or disabled persons. SSI is provided to eligible aged or disabled individuals or couples who have limited income and resources.
Date: January 8, 2008
Creator: Szymendera, Scott
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

Description: The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%… more
Date: January 8, 2008
Creator: Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

CP Violation at BaBar

Description: Several new and updated BABAR measurements of sin 2{beta} are presented, together with the latest constraints on the Unitarity Triangle angles {alpha} and {gamma}. The higher statistics now available allow more sophisticated analysis techniques, such as time-dependent Dalitz plot fitting. Combined world-average results place tight constraints on the Unitarity Triangle. There is good agreement among the measurements and with the unitarity of the CKM matrix. This represents an impressive verifica… more
Date: January 8, 2008
Creator: Hawkes, Chris & U., /Birmingham
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Low-Temperature Synthesis Routes to Intermetallic Superconductors

Description: Over the past few years, our group has gained expertise at developing low-temperature solution-based synthetic pathways to complex nanoscale solids, with particular emphasis on nanocrystalline intermetallic compounds. Our synthetic capabilities are providing tools to reproducibly generate intermetallic nanostructures with simultaneous control over crystal structure, composition, and morphology. This DOE-funded project aims to expand these capabilities to intermetallic superconductors. This coul… more
Date: January 8, 2008
Creator: Schaak, Raymond E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Slow Waves in Fractures Filled with Viscous Fluid

Description: Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type so… more
Date: January 8, 2008
Creator: Korneev, Valeri
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of D^0-\overline{D^0} Mixing using the Ratio of Lifetimes for the Decays D^0 \to K^-\pi^+, K^-K^+, and \pi^-\pi^+

Description: The authors present a measurement of D{sup 0}-{bar D}{sup 0} mixing parameters using the ratios of lifetimes extracted from a sample of D{sup 0} mesons produced through the process D*{sup +} {yields} D{sup 0}{pi}{sup +}, that decay to K{sup -}{pi}{sup +}, I{sup -}K{sup +}, or {pi}{sup -}{pi}{sup +}. the Cabibbo-suppressed modes K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} are compared to the Cabibbo-favored mode K{sup -}{pi}{sup +} to obtain a measurement of ycp, which in the limit of CP conserv… more
Date: January 8, 2008
Creator: Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

Description: We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of th… more
Date: January 8, 2008
Creator: Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transverse Effects Due to Random Displacement of Resistive Wall Segments and Focusing Elements

Description: In this paper, we study the single bunch transverse beam dynamics in the presence of random displacements of resistive wall segments and focusing elements. Analytical formulas are obtained for long-range resistive wall wake, together with numerical results for short-range resistive wall wake. The results are applied to the LCLS project and some other proposed accelerators.
Date: January 8, 2008
Creator: Delayen, J.R.; U., /Jefferson Lab /Old Dominion & Wu, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Network Communication as a Service-Oriented Capability

Description: In widely distributed systems generally, and in science-oriented Grids in particular, software, CPU time, storage, etc., are treated as"services" -- they can be allocated and used with service guarantees that allows them to be integrated into systems that perform complex tasks. Network communication is currently not a service -- it is provided, in general, as a"best effort" capability with no guarantees and only statistical predictability. In order for Grids (and most types … more
Date: January 8, 2008
Creator: Johnston, William; Johnston, William; Metzger, Joe; Collins, Michael; Burrescia, Joseph; Dart, Eli et al.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
open access

Supersymmetric Model Builing (and Sweet Spot Supersymmetry)

Description: It has been more than twenty years since theorists started discussing supersymmetric model building/phenomenology. We review mechanisms of supersymmetry breaking/mediation and problems in each scenario. We propose a simple model to address those problems and discuss its phenomenology.
Date: January 8, 2008
Creator: Ibe, Masahiro; /SLAC /Stanford U., Phys. Dept.; Kitano, Ryuichiro & Alamos, /Los
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transverse Effect Due to Short Range Resistive Wall Wakefield

Description: For accelerator designs with ultra short electron beams, beam dynamics study has to invoke the short-range wakefields. In this paper, we first obtain the short-range dipole mode resistive wall wakefield. Analytical approach is then developed to study the single bunch transverse beam dynamics due to this short-range resistive wall wake. The results are applied to the LCLS undulator.
Date: January 8, 2008
Creator: Delayen, J. R.; Chao, Alexander Wu & Wu, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Self Consistent Monte Carlo Method to Study CSR Effects in Bunch Compressors

Description: In this paper we report on the results of a self-consistent calculation of CSR effects on a particle bunch moving through the benchmark Zeuthen bunch compressors. The theoretical framework is based on a 4D Vlasov-Maxwell approach including shielding from the vacuum chamber. We calculate the fields in the lab frame, where time is the independent variable, and evolve the phase space density/points in the beam frame, where arc length, s, along a reference orbit, is the independent variable. Some d… more
Date: January 8, 2008
Creator: Warnock, R. L.; Bassi, G.; Ellison, J. A. & Heinemann, K. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Wetting of metals and glasses on Mo

Description: The wetting of low melting point metals and Si-Ca-Al-Ti-O glasses on molybdenum has been investigated. The selected metals (Au, Cu, Ag) form a simple eutectic with Mo. Metal spreading occurs under nonreactive conditions without interdiffusion or ridge formation. The metals exhibit low (non-zero) contact angles on Mo but this requires temperatures higher than 1100 C in reducing atmospheres in order to eliminate a layer of adsorbed impurities on the molybdenum surface. By controlling the oxygen a… more
Date: January 8, 2008
Creator: Saiz, Eduardo; Tomsia, Antoni P.; Saiz, Eduardo; Lopez-Esteban, Sonia; Benhassine, Mehdi; de Coninck, Joel et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Coherent Synchrotron Radiation and Space Charge for a 1-D Bunch on an Arbitrary Planar Orbit

Description: Realistic modeling of coherent synchrotron radiation (CSR) and the space charge force in single-pass systems and rings usually requires at least a two-dimensional (2-D) description of the charge/current density of the bunch. Since that leads to costly computations, one often resorts to a 1-D model of the bunch for first explorations. This paper provides several improvements to previous 1-D theories, eliminating unnecessary approximations and physical restrictions.
Date: January 8, 2008
Creator: Warnock, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Fourth-Order Method for Numerical Integration of Age- and Size-Structured Population Models

Description: In many applications of age- and size-structured population models, there is an interest in obtaining good approximations of total population numbers rather than of their densities. Therefore, it is reasonable in such cases to solve numerically not the PDE model equations themselves, but rather their integral equivalents. For this purpose quadrature formulae are used in place of the integrals. Because quadratures can be designed with any order of accuracy, one can obtain numerical approximation… more
Date: January 8, 2008
Creator: Iannelli, M; Kostova, T & Milner, F A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Trade Negotiations During the 110th Congress

Description: This report discusses the trade negotiations during Bush Administration, which has made bilateral and regional free-trade agreements (FTAs) an important element of U.S. trade policy, a strategy known as “competitive liberalization.”
Date: January 8, 2008
Creator: Fergusson, Ian F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Social Security Survivors Benefits

Description: This report describes how a person becomes covered by Survivors Insurance. It outlines the types and amounts of benefits available to survivors, eligibility for those benefits, and the benefit application process. It provides statistics on survivor beneficiaries and a legislative history of Survivors Insurance, including legislative activity in the 110th Congress.
Date: January 8, 2008
Creator: Romig, Kathleen & Szymendera, Scott
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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