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Defense Acquisitions: Role of Lead Systems Integrator on Future Combat Systems Program Poses Oversight Challenges

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Army's Future Combat Systems (FCS) program features multiple new systems linked by a first-of-a-kind information network. The Army contracted with a lead systems integrator (LSI) for FCS that could serve in a more expansive role than a typical prime contractor would. In response to a congressional mandate, this report addresses (1) why the Army decided to employ an LSI for the FCS program; (2) the n… more
Date: June 6, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Monte Carlo Methods in the Physical Sciences

Description: I will review the role that Monte Carlo methods play in the physical sciences. They are very widely used for a number of reasons: they permit the rapid and faithful transformation of a natural or model stochastic process into a computer code. They are powerful numerical methods for treating the many-dimensional problems that derive from important physical systems. Finally, many of the methods naturally permit the use of modern parallel computers in efficient ways. In the presentation, I will em… more
Date: June 6, 2007
Creator: Kalos, M. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

D-dualized D-brane

Description: We further investigate the dimensional duality (D-duality) proposed in arXiv: 0705.0550 by mainly focusing on the properties of D-branes in this background. We derive the world-sheet correspondence of static D-branes, and discuss the fate of non-static D-branes from the world-sheet viewpoint. The quantum string production with or without D-branes is also studied fromthe time-like Liouville theory. We find that the closed string production from the background is much larger than that from D-bran… more
Date: June 6, 2007
Creator: Nakayama, Yu & Nakayama, Yu
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Isopiestic Investigation of the Osmotic and Activity Coefficients of {yMgCl2 + (1 - y)MgSO4}(aq) and the Osmotic Coefficients of Na2SO4.MgSO4(aq) at 298.15 K

Description: Isopiestic vapor pressure measurements were made for {l_brace}yMgCl{sub 2} + (1-y)MgSO{sub 4}{r_brace}(aq) solutions with MgCl{sub 2} ionic strength fractions of y = 0, 0.1997, 0.3989, 0.5992, 0.8008, and (1) at the temperature 298.15 K, using KCl(aq) as the reference standard. These measurements for the mixtures cover the ionic strength range I = 0.9794 to 9.4318 mol {center_dot} kg{sup -1}. In addition, isopiestic measurements were made with NaCl(aq) as reference standard for mixtures of {l_b… more
Date: June 6, 2007
Creator: Miladinovic, J; Ninkovic, R; Todorovic, M & Rard, J A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Remote Monitoring and Tracking of UF6 Cylinders Using Long-Range Passive Ultra-wideband (UWB) RFID Tags

Description: An IAEA Technical Meeting on Techniques for IAEA Verification of Enrichment Activities identified 'smart tags' as a technology that should be assessed for tracking and locating UF6 cylinders. Although there is vast commercial industry working on RFID systems, the vulnerabilities of commercial products are only beginning to emerge. Most of the commercially off-the-shelf (COTS) RFID systems operate in very narrow frequency bands, making them vulnerable to detection, jamming and tampering and also… more
Date: June 6, 2007
Creator: Nekoogar, F. & Dowla, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermal degradation in a trimodal PDMS network by 1H Multiple Quantum NMR

Description: Thermal degradation of a filled, crosslinked siloxane material synthesized from PDMS chains of three different average molecular weights and with two different crosslinking species has been studied by {sup 1}H Multiple Quantum (MQ) NMR methods. Multiple domains of polymer chains were detected by MQ NMR exhibiting Residual Dipolar Coupling (<{Omega}{sub d}>) values of 200 Hz and 600 Hz, corresponding to chains with high average molecular weight between crosslinks and chains with low averag… more
Date: June 6, 2007
Creator: Giuliani, J R; Gjersing, E L; Chinn, S C; Jones, T V; Wilson, T S; Alviso, C T et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Bobbin-Tool Friction-Stir Welding of Thick-Walled Aluminum Alloy Pressure Vessels

Description: It was desired to assemble thick-walled Al alloy 2219 pressure vessels by bobbin-tool friction-stir welding. To develop the welding-process, mechanical-property, and fitness-for-service information to support this effort, extensive friction-stir welding-parameter studies were conducted on 2.5 cm. and 3.8 cm. thick 2219 Al alloy plate. Starting conditions of the plate were the fully-heat-treated (-T62) and in the annealed (-O) conditions. The former condition was chosen with the intent of using … more
Date: June 6, 2007
Creator: Dalder, E C; Pastrnak, J W; Engel, J; Forrest, R S; Kokko, E; Ternan, K M et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Peaceful Uses Bona Fides: Criteria for Evaluation and Case Studies

Description: This study applies a set of indicators to assess the peaceful nature of a state’s nuclear program. Evaluation of a country’s nuclear program relative to these indicators can help the international community to take appropriate actions to ensure that the growth of the global nuclear energy industry proceeds peacefully and to minimize nuclear proliferation risks.
Date: June 6, 2007
Creator: Ajemian, Chris K.; Hazel, Mike; Kessler, Carol E.; Mathews, Carrie E.; Morris, Fred A.; Seward, Amy M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simulation of Gamma Rays from Proton Interaction in Local Galaxies

Description: The GLAST Large Area Telescope will provide unprecedented opportunities to detect cosmic GeV gamma rays, thanks to its large effective area, field of view and angular resolution compared with earlier telescopes. We present here the possibility of detecting GeV gamma rays produced by interactions of accelerated protons (or hadrons) with surrounding ambient material. Sources where such detection could be made include local galaxies, such as the Large Magellanic Cloud (LMC), molecular clouds and o… more
Date: June 6, 2007
Creator: Karlsson, Niklas; U., /SLAC /Stockholm; Cohen-Tanugi, Johann; Kamae, Tuneyoshi; Tajima, Hiroyasu & /SLAC /KIPAC, Menlo Park
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

CHARACTERIZATION OF DWPF MELTER OFF-GAS QUENCHER AND STEAM ATOMIZED SCRUBBER DEPOSIT SAMPLES

Description: This report summarizes the results from the characterization of deposits from the inlets of the primary off-gas Quencher and Steam Atomized Scrubber (SAS) in the Defense Waste Processing Facility (DWPF), as requested by a technical assistance request. DWPF requested elemental analysis and compound identification to help determine the potential causes for the substance formation. This information will be fed into Savannah River National Laboratory modeling programs to determine if there is a way… more
Date: June 6, 2007
Creator: Zeigler, K & Ned Bibler, N
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Open Access Publishing in Particle Physics: A Brief Introduction for the Non-Expert

Description: Open Access to particle physics literature does not sound particularly new or exciting, since particle physicists have been reading preprints for decades, and arXiv.org for 15 years. However new movements in Europe are attempting to make the peer-reviewed literature of the field fully Open Access. This is not a new movement, nor is it restricted to this field. However, given the field's history of preprints and eprints, it is well suited to a change to a fully Open Access publishing model. Data… more
Date: June 6, 2007
Creator: Brooks, Travis C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Is There Evidence for a Hubble Bubble? The Nature of SN Ia Colors And Dust in External Galaxies

Description: We examine recent evidence from the luminosity-redshift relation of Type Ia Supernovae for the {approx} 3 {sigma} detection of a ''Hubble bubble'' -- a departure of the local value of the Hubble constant from its globally averaged value. By comparing the MLCS2k2 fits used in that study to the results from other light-curve fitters applied to the same data, we demonstrate that this is related to the interpretation of SN color excesses (after correction for a light-curve shape-color relation) and… more
Date: June 6, 2007
Creator: Conley, A.; Carlberg, R. G.; Guy, J.; Howell, D. A.; Jha, S.; Riess, A. G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Final Technical Report

Description: The following report contributes to our knowledge of how to economically produce wildlife-friendly grass mixtures for future fuel feedstocks in the northern plains. It investigates northern-adapted cultivars; management and harvest regimes that are good for yields, soils and wildlife; comparative analysis of monocultures and simple mixtures of native grasses; economic implications of growing grasses for fuel feedstocks in specific locations in the northern plains; and conversion options for tur… more
Date: June 6, 2007
Creator: Sara Bergan, Executive Director; Brendan Jordan, Program Manager & report., Subcontractors as listed on the
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Structural insights into microtubule doublet interactions inaxonemes

Description: Coordinated sliding of microtubule doublets, driven by dynein motors, produces periodic beating of the axoneme. Recent structural studies of the axoneme have used cryo-electron tomography to reveal new details of the interactions among some of the multitude of proteins that form the axoneme and regulate its movement. Connections among the several sets of dyneins, in particular, suggest ways in which their actions may be coordinated. Study of the molecular architecture of isolated doublets has p… more
Date: June 6, 2007
Creator: Downing, Kenneth H. & Sui, Haixin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Asymptotic Behavior of the Electron Cloud Instability

Description: The fast beam-ion instability and the single bunch electron-cloud instability are substantially nonlinear phenomena and can be analyzed in a similar way. The initial exponential growth of the amplitudes known for both instabilities takes place only in the linear approximation. Later, in the nonlinear regime, amplitudes grow according to a power law or even decrease. We analyze the nonlinear regime describing the growth of amplitudes in time and along the train of bunches. Analytic analysis is c… more
Date: June 6, 2007
Creator: Heifets, Samuel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

New Constraints on Dark Energy from Chandra X-rayObservations of the Largest Relaxed Galaxy Clusters

Description: We present constraints on the mean matter density, {Omega}{sub m}, dark energy density, {Omega}{sub DE}, and the dark energy equation of state parameter, w, using Chandra measurements of the X-ray gas mass fraction (fgas) in 42 hot (kT > 5keV), X-ray luminous, dynamically relaxed galaxy clusters spanning the redshift range 0.05 < z < 1.1. Using only the fgas data for the 6 lowest redshift clusters at z < 0.15, for which dark energy has a negligible effect on the measurements, we mea… more
Date: June 6, 2007
Creator: Allen, S. W.; Rapetti, D. A.; Schmidt, R. W.; Ebeling, H.; Morris, G. & Fabian, A. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Is There a Quad Problem Among Pptical Gravitational Lenses?

Description: Most of optical gravitational lenses recently discovered in the Sloan Digital Sky Survey Quasar Lens Search (SQLS) have two-images rather than four images, in marked contrast to radio lenses for which the fraction of four-image lenses (quad fraction) is quite high. We revisit the quad fraction among optical lenses by taking the selection function of the SQLS into account. We find that the current observed quad fraction in the SQLS is indeed lower than, but consistent with, the prediction of our… more
Date: June 6, 2007
Creator: Oguri, Masamune
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA.,Volume III. P-Wave Measurements in Borehole C4997 Seismic Records, Wave-Arrival Identifications and Interpreted P-Wave Velocity Profile.

Description: In this volume (III), all P-wave measurements are presented that were performed in Borehole C4997 at the Waste Treatment Plant (WTP) with T-Rex as the seismic source and the Lawrence Berkeley National Laboratory (LBNL) 3-D wireline geophone as the at-depth borehole receiver. P-wave measurements were performed over the depth range of 390 to 1220 ft, typically in 10-ft intervals. However, in some interbeds, 5-ft depth intervals were used. Compression (P) waves were generated by moving the base pl… more
Date: June 6, 2007
Creator: Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R. & Menq, Farn-Yuh
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

RADIOACTIVE MATERIAL SHIPPING PACKAGINGS AND METAL TO METAL SEALS FOUND IN THE CLOSURES OF CONTAINMENT VESSELS INCORPORATING CONE SEAL CLOSURES

Description: The containment vessels for the Model 9975 radioactive material shipping packaging employ a cone-seal closure. The possibility of a metal-to-metal seal forming between the mating conical surfaces, independent of the elastomer seals, has been raised. It was postulated that such an occurrence would compromise the containment vessel hydrostatic and leakage tests. The possibility of formation of such a seal has been investigated by testing and by structural and statistical analyses. The results of … more
Date: June 6, 2007
Creator: Loftin, B; Glenn Abramczyk, G & Allen Smith, A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Determination of the Form Factors for the Decay B0 to D*- l+ nu_l and of the CKM Matrix Element |Vcb|

Description: We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub cb}| and of the parameters {rho}{sup 2}, R{sub 1}(1), and R{sub 2}(1), which fully characterize the form factors for the B{sup 0} {yields} D*-{ell}+?{sub {ell}} decay in the framework of HQET. The results, based on a selected sample of about 52,800 B{sup 0} {yields} D*-{ell}+?{sub {ell}} decays, recorded by the BABAR detector, are {rho}{sup 2} = 1.156 {+-} 0.094 {+-} 0.028, R{sub 1}(1) = 1.329{+-}0.131{+-}0… more
Date: June 6, 2007
Creator: Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA,Volume VI. S-Wave Measurements in Borehole C4997 Seismic Records, Wave-Arrival Identifications and Interpreted S-Wave Velocity Profile.

Description: Velocity measurements in shallow sediments from ground surface to approximately 370 to 400 feet bgs were collected by Redpath Geophysics using impulsive S- and P-wave seismic sources (Redpath 2007). Measurements below this depth within basalt and sedimentary interbeds were made by UTA between October and December 2006 using the T-Rex vibratory seismic source in each of the three boreholes. Results of these measurements including seismic records, wave-arrival identifications and interpreted velo… more
Date: June 6, 2007
Creator: Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R. & Menq, Farn-Yuh
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sweet Spot Supersymmetry

Description: We find that there is no supersymmetric flavor/CP problem, {mu}-problem, cosmological moduli/gravitino problem or dimension four/five proton decay problem in a class of supersymmetric theories with O(1) GeV gravitino mass. The cosmic abundance of the nonthermally produced gravitinos naturally explains the dark matter component of the universe. A mild hierarchy between the mass scale of supersymmetric particles and electroweak scale is predicted, consistent with the null result of a search for t… more
Date: June 6, 2007
Creator: Ibe, Masahiro; Kitano, Ryuichiro & /SLAC /Stanford U., Phys. Dept.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Deep Downhole Seismic Testing at the Waste Treatment Plant Site, Hanford, WA,Volume V. S-Wave Measurements in Borehole C4996 Seismic Records, Wave-Arrival Identifications and Interpreted S-Wave Velocity Profile.

Description: Velocity measurements in shallow sediments from ground surface to approximately 370 to 400 feet bgs were collected by Redpath Geophysics using impulsive S- and P-wave seismic sources (Redpath 2007). Measurements below this depth within basalt and sedimentary interbeds were made by UTA between October and December 2006 using the T-Rex vibratory seismic source in each of the three boreholes. Results of these measurements including seismic records, wave-arrival identifications and interpreted velo… more
Date: June 6, 2007
Creator: Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R. & Menq, Farn-Yuh
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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