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Intelligence, Surveillance, and Reconnaissance: DOD Can Better Assess and Integrate ISR Capabilities and Oversee Development of Future ISR Requirements (open access)

Intelligence, Surveillance, and Reconnaissance: DOD Can Better Assess and Integrate ISR Capabilities and Oversee Development of Future ISR Requirements

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense's (DOD) intelligence, surveillance, and reconnaissance (ISR) capabilities-such as satellites and unmanned aircraft systems-are crucial to military operations, and demand for ISR capabilities has increased. For example, DOD plans to invest $28 billion over the next 7 years in 20 airborne ISR systems alone. Congress directed DOD to fully integrate its ISR capabilities, also known as the ISR enterprise, as it works to meet current and future ISR needs. GAO was asked to (1) describe the challenges, if any, that DOD faces in integrating its ISR enterprise, (2) assess DOD's management approach for improving integration of its future ISR investments, and (3) evaluate the extent to which DOD has implemented key activities to ensure proposed new ISR capabilities fill gaps, are not duplicative, and use a joint approach to meeting warfighters' needs. GAO assessed DOD's integration initiatives and 19 proposals for new ISR capabilities. We supplemented this analysis with discussions with DOD officials."
Date: March 24, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Measurement of the tau- to eta pi-pi+pi-nu tau Branching Fraction and a Search for a Second-Class Current in the tau- to eta'(958)pi-nu tau Decay (open access)

Measurement of the tau- to eta pi-pi+pi-nu tau Branching Fraction and a Search for a Second-Class Current in the tau- to eta'(958)pi-nu tau Decay

The {tau}{sup -} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} decay with the {eta} {yields} {gamma}{gamma} mode is studied using 384 fb{sup -1} of data collected by the BABAR detector. The branching fraction is measured to be (1.60 {+-} 0.05 {+-} 0.11) x 10{sup -4}. It is found that {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -} {nu}{sub {tau}} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} is the dominant decay mode with a branching fraction of (1.11 {+-} 0.06 {+-} 0.05) x 10{sup -4}. The first error on the branching fractions is statistical and the second systematic. In addition, a 90% confidence level upper limit on the branching fraction of the {tau}{sup -} {yields} {eta}{prime}(958){pi}{sup -}{nu}{sub {tau}} decay is measured to be 7.2 x 10{sup -6}. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.
Date: March 24, 2008
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type: Article
System: The UNT Digital Library
Analyses of Oxyanion Materials by Prompt Gamma Activation Analysis (open access)

Analyses of Oxyanion Materials by Prompt Gamma Activation Analysis

Prompt gamma activation analysis (PGAA) has been used to analyze metal ion oxyanion materials that have multiple applications, including medicine, materials, catalysts, and electronics. The significance for the need for accurate, highly sensitive analyses for the materials is discussed in the context of quality control of end products containing the parent element in each material. Applications of the analytical data for input to models and theoretical calculations related to the electronic and other properties of the materials are discussed.
Date: March 24, 2008
Creator: Firestone, Richard B.; Perry, D. L.; English, G. A.; Firestone, R. B.; Leung, K. N.; Garabedian, G. et al.
Object Type: Article
System: The UNT Digital Library
Development of a Multi Megawatt Circulator for X Band (open access)

Development of a Multi Megawatt Circulator for X Band

Research is in progress on a TeV-scale linear collider that will operate at 5-10 times the energy of present-generation accelerators. This will require development of high power RF sources generating of 50-100 MW per source. Transmission of power at this level requires overmoded waveguide to avoid breakdown. In particular, the TE{sub 01} circular waveguide mode is currently the mode of choice for waveguide transmission at Stanford Linear Accelerator Center (SLAC) in the Multimode Delay Line Distribution System (MDLDS). A common device for protecting an RF source from reflected power is the waveguide circulator. A circulator is typically a three-port device that allows low loss power transmission from the source to the load, but diverts power coming from the load (reflected power) to a third terminated port. To achieve a low loss, matched, three port junction requires nonreciprocal behavior. This is achieved using ferrites in a static magnetic field which introduces a propagation constant dependent on RF field direction relative to the static magnetic field. Circulators are currently available at X-Band for power levels up to 1 MW in fundamental rectangular waveguide; however, the next generation of RF sources for TeV-level accelerators will require circulators in the 50-100 MW range. Clearly, …
Date: March 24, 2008
Creator: Neilson, J.; Ives, L. & Tantawi, S. G.
Object Type: Article
System: The UNT Digital Library
Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study (open access)

Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of theabsorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z< 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.
Date: March 24, 2008
Creator: Supernova Cosmology Project
Object Type: Article
System: The UNT Digital Library
An Integrated Assessment of Geochemical and Community Structure Determinants of Metal Reduction Rates in Subsurface Sediments (open access)

An Integrated Assessment of Geochemical and Community Structure Determinants of Metal Reduction Rates in Subsurface Sediments

This project represented a joint effort between Oak Ridge National Laboratory (ORNL), the University of Tennessee (UT), and Florida State University (FSU). ORNL served as the lead in-stitution with Dr. A.V. Palumbo responsible for project coordination, integration, and deliver-ables. In situ uranium bioremediation is focused on biostimulating indigenous microorganisms through a combination of pH neutralization and the addition of large amounts of electron donor. Successful biostimulation of U(VI) reduction has been demonstrated in the field and in the laboratory. However, little data is available on the dynamics of microbial populations capable of U(VI) reduction, and the differences in the microbial community dynamics between proposed electron donors have not been explored. In order to elucidate the potential mechanisms of U(VI) reduction for optimization of bioremediation strategies, structure-function relationships of microbial populations were investigated in microcosms of subsurface materials cocontaminated with radionuclides and nitrate from the Oak Ridge Field Research Center (ORFRC), Oak Ridge, Tennessee.
Date: March 24, 2008
Creator: Kostka, Joel E.
Object Type: Report
System: The UNT Digital Library
Actinic EUV mask inspection beyond 0.25 NA (open access)

Actinic EUV mask inspection beyond 0.25 NA

The SEMATECH Berkeley Actinic Inspection Tool (AIT) is an EUV-wavelength mask inspection microscope designed for direct aerial image measurements, and pre-commercial EUV mask research. Operating on a synchrotron bending magnet beamline, the AIT uses an off-axis Fresnel zoneplate lens to project a high-magnification EUV image directly onto a CCD camera. We present the results of recent system upgrades that have improved the imaging resolution, illumination uniformity, and partial coherence. Benchmarking tests show image contrast above 75% for 100-nm mask features, and significant improvements and across the full range of measured sizes. The zoneplate lens has been replaced by an array of user-selectable zoneplates with higher magnification and NA values up to 0.0875, emulating the spatial resolution of a 0.35-NA 4x EUV stepper. Illumination uniformity is above 90% for mask areas 2-{micro}m-wide and smaller. An angle-scanning mirror reduces the high coherence of the synchrotron beamline light source giving measured {sigma} values of approximately 0.125 at 0.0875 NA.
Date: March 24, 2008
Creator: Goldberg, Kenneth A.; Mochi, Iacopo; Anderson, Erik H.; Rekawa, Seno. B.; Kemp, Charles D.; Huh, S. et al.
Object Type: Article
System: The UNT Digital Library
NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON (open access)

NUCLEAR WASTE GLASSES CONTINUOUS MELTING AND BULK VITRIFICAITON

This contribution addresses various aspects of nuclear waste vitrification. Nuclear wastes have a variety of components and composition ranges. For each waste composition, the glass must be formulated to possess acceptable processing and product behavior defined in terms of physical and chemical properties that guarantee the glass can be easily made and resist environmental degradation. Glass formulation is facilitated by developing property-composition models, and the strategy of model development and application is reviewed. However, the large variability of waste compositions presents numerous additional challenges: insoluble solids and molten salts may segregate; foam may hinder heat transfer and slow down the process; molten salts may accumulate in container refractory walls; the glass on cooling may precipitate crystalline phases. These problems need targeted exploratory research. Examples of specific problems and their possible solutions are discussed.
Date: March 24, 2008
Creator: AA, KRUGER & PR, HRMA
Object Type: Article
System: The UNT Digital Library
Design and Test of a 100MW X Band TE01 Window (open access)

Design and Test of a 100MW X Band TE01 Window

Research at Stanford Linear Accelerator Center (SLAC) is in progress on a TeV-scale linear collider that will operate at 5-10 times the energy of present generation accelerators. This will require development of high power X-Band sources generating 50-100 MW per source. Conventional pillbox window designs are capable of transmitting peak rf powers up to about 30 MW, well below the desired level required for the use of a single window per tube. SLAC has developed a 75 MW TE{sub 01} window [1] that uses a 'traveling wave' design to minimize fields at the window face. Irises match to the dielectric window impedance, resulting in a pure traveling wave in the ceramic and minimum fields on the window face. The use of the TE{sub 01} mode also has zero electric field on the braze fillet. Unfortunately, in-band resonances prevented this window design from achieving the desired 75MW power level. It was believed the resonances resulted from sudden steps in the circular guide to match the 38mm input diameter to the overmoded (TE{sub 01} and TE{sub 02} mode propagating) 65 mm diameter of the window ceramic. Calabazas Creek Research Inc. is currently developing a traveling wave window using compact, numerically optimized, parabolic …
Date: March 24, 2008
Creator: Neilson, J.; Ives, L. & Tantawi, S. G.
Object Type: Article
System: The UNT Digital Library
Rapid Formation of Supermassive Black Hole Binaries in Galaxy Mergers with Gas (open access)

Rapid Formation of Supermassive Black Hole Binaries in Galaxy Mergers with Gas

Supermassive black holes (SMBHs) are a ubiquitous component of the nuclei of galaxies. It is normally assumed that, following the merger of two massive galaxies, a SMBH binary will form, shrink due to stellar or gas dynamical processes and ultimately coalesce by emitting a burst of gravitational waves. However, so far it has not been possible to show how two SMBHs bind during a galaxy merger with gas due to the difficulty of modeling a wide range of spatial scales. Here we report hydrodynamical simulations that track the formation of a SMBH binary down to scales of a few light years following the collision between two spiral galaxies. A massive, turbulent nuclear gaseous disk arises as a result of the galaxy merger. The black holes form an eccentric binary in the disk in less than a million years as a result of the gravitational drag from the gas rather than from the stars.
Date: March 24, 2008
Creator: Mayer, L.; Kazantzidis, S.; Madau, P.; Colpi, M.; Quinn, T. & Wadsley, J.
Object Type: Article
System: The UNT Digital Library
Issues Affecting Tidal, Wave, and In-Stream Generation Projects (open access)

Issues Affecting Tidal, Wave, and In-Stream Generation Projects

This report discusses policy guidance on energy sources that generates electricity from ocean waves, tides, and river currents. The report provides background information and legislation regarding these energy sources and technologies.
Date: March 24, 2008
Creator: Lane, Nic
Object Type: Report
System: The UNT Digital Library
Federal Tort Claims Act (open access)

Federal Tort Claims Act

None
Date: March 24, 2008
Creator: Cohen, Henry & Burrows, Vanessa K.
Object Type: Report
System: The UNT Digital Library
[Letter from Gary Borders to Dave Rogers, March 24, 2008] (open access)

[Letter from Gary Borders to Dave Rogers, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Dave Rogers, Sports Writer the Baytown Sun, on March 24, 2008. The letter congratulations Rogers on winning the Fred Hartman Excellence in Sportswriting Award, and that Borders had the pleasure of presenting him the award.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Paul Caluori, March 24, 2008] (open access)

[Letter from Gary Borders to Paul Caluori, March 24, 2008]

Letter from Gary Borders, President at TDNA, to Paul Caluori, Director APT at Associated Press, on March 24, 2008. The letter is in regards on the behalf of the officers and directors of TDNA thanking Caluori for his participation at the 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Charles Moser, March 24, 2008] (open access)

[Letter from Gary Borders to Charles Moser, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Charles Moser, Editor and Publisher for the Banner-Press, on March 24, 2008. The letter is in regards to Borders' appreciation for Moser presiding the Monday luncheon at the TDNA's 87th annual meeting in San Antonio.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Patrick Birmingham, March 24, 2008] (open access)

[Letter from Gary Borders to Patrick Birmingham, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Patrick Birmingham, President and Publisher of the Corpus Christi Caller-Times on March 24, 2008. The letter is in regards to Birmingham doing a great job of presiding the Tuesday morning business session at TDNA's 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to John Lumpkin, March 24, 2008] (open access)

[Letter from Gary Borders to John Lumpkin, March 24, 2008]

Letter from Gary Borders, President of the Texas Daily Newspaper Association, to John Lumpkin, Vice President of Business Operations at Associated Press, on March 24, 2008. The letter is on the behalf of the officers and directors of TDNA and Borders wanted to thank Lumpkin for his participation on this year's 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Jim Abbott, March 24, 2008] (open access)

[Letter from Gary Borders to Jim Abbott, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Jim Abbott, Vice President NAA Foundation on March 24, 2008. The letter is in regards on behalf of the officers and directors of TDNA appreciation that Abbott was apart of the TDNA's 2008 Annual Meeting, and that his presentation was interesting and informative.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Doug Toney, March 24, 2008] (open access)

[Letter from Gary Borders to Doug Toney, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Doug Toney, Publisher at the Herald-Zeitung, on March 24, 2008. The letter congratulates Toney on winning the Pat Taggart Award, and Borders states that that Toney is a worthy recipient.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Laura Prather, March 24, 2008] (open access)

[Letter from Gary Borders to Laura Prather, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Laura Prather, partner at Sedgwick, Detert, Moran & Arnold LLP, on March 24, 2008. The letter is on the behalf of the officers and directors of TDNA who want to thank Prather for participating in the annual meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Shannon Edwards, March 24, 2008] (open access)

[Letter from Gary Borders to Shannon Edwards, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Shannon Edmonds, Director of Governmental Relations at TDCCA, on March 24, 2008. The letter is on behalf of the officers and directors of TDNA wanting to thank Edmonds for her participation at the 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Fred B. Hartman, March 24, 2008] (open access)

[Letter from Gary Borders to Fred B. Hartman, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Fred B. Hartman, Vice President of Hartman Newspapers, LP, on March 24, 2008. The letter thanks Hartman for moderating the TDNA's 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Julie Weber, March 24, 2008] (open access)

[Letter from Gary Borders to Julie Weber, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Julie Weber General Manager, My San Antonio.com, Express News, on March 24, 2008. The letter is on behalf of the officers and directors of TDNA who want to express their appreciation that Weber was part of the TDNA's 2008 Annual meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library
[Letter from Gary Borders to Stephen Weis, March 24, 2008] (open access)

[Letter from Gary Borders to Stephen Weis, March 24, 2008]

Letter from Gary Borders, President of TDNA, to Stephen Weis, VP General Manager, chron.com, Houston Chronicle, on March 24, 2008. The letter is on behalf of the officers and directors of TDNA wanting to express their appreciation for Weis' participation at the 87th Annual Meeting.
Date: March 24, 2008
Creator: Borders, Gary
Object Type: Letter
System: The UNT Digital Library