First Responders: Much Work Remains to Improve Communications Interoperability (open access)

First Responders: Much Work Remains to Improve Communications Interoperability

A letter report issued by the Government Accountability Office with an abstract that begins "As the first to respond to natural disasters, domestic terrorism, and other emergencies, public safety agencies rely on timely communications across multiple disciplines and jurisdictions. It is vital to the safety and effectiveness of first responders that their electronic communications systems enable them to communicate with whomever they need to, when they need to, and when they are authorized to do so. GAO was asked to determine, among other things, (1) the extent to which Department of Homeland Security (DHS) funding and technical assistance has helped to improve interoperable communications in selected states and (2) the progress that has been made in the development and implementation of interoperable communications standards. To address these objectives, GAO reviewed grant information, documentation of selected states' and localities' interoperability projects, and standards documents."
Date: April 2, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Tactical Aircraft: DOD Needs a Joint and Integrated Investment Strategy (open access)

Tactical Aircraft: DOD Needs a Joint and Integrated Investment Strategy

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Defense (DOD) plans to invest $109 billion in its tactical air forces between 2007 and 2013. Long term, DOD plans to replace aging legacy aircraft with fewer, more expensive but more capable and stealthy aircraft. Recapitalizing and modernizing tactical air forces within today's constrained budget environment is a formidable challenge. DOD has already incurred substantial cost and schedule overruns in its acquisition of new systems, and further delays could require billions of dollars in additional investments to keep legacy aircraft capable and sustainable. Because of the large investments and risk, GAO was asked to review investment planning for tactical aircraft. This report describes the current status of DOD's new tactical aircraft acquisition programs; identifies current impacts on legacy aircraft modernization programs and retirement schedules; and assesses DOD's overall investment plan for tactical aircraft."
Date: April 2, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Relativistic Flows Using Spatial And Temporal Adaptive Structured Mesh Refinement. I. Hydrodynamics (open access)

Relativistic Flows Using Spatial And Temporal Adaptive Structured Mesh Refinement. I. Hydrodynamics

Astrophysical relativistic flow problems require high resolution three-dimensional numerical simulations. In this paper, we describe a new parallel three-dimensional code for simulations of special relativistic hydrodynamics (SRHD) using both spatially and temporally structured adaptive mesh refinement (AMR). We used method of lines to discrete SRHD equations spatially and used a total variation diminishing (TVD) Runge-Kutta scheme for time integration. For spatial reconstruction, we have implemented piecewise linear method (PLM), piecewise parabolic method (PPM), third order convex essentially non-oscillatory (CENO) and third and fifth order weighted essentially non-oscillatory (WENO) schemes. Flux is computed using either direct flux reconstruction or approximate Riemann solvers including HLL, modified Marquina flux, local Lax-Friedrichs flux formulas and HLLC. The AMR part of the code is built on top of the cosmological Eulerian AMR code enzo, which uses the Berger-Colella AMR algorithm and is parallel with dynamical load balancing using the widely available Message Passing Interface library. We discuss the coupling of the AMR framework with the relativistic solvers and show its performance on eleven test problems.
Date: April 2, 2007
Creator: Wang, Peng; Abel, Tom; Zhang, Weiqun & /KIPAC, Menlo Park
Object Type: Report
System: The UNT Digital Library
Self-Consistent 3D Modeling of Electron Cloud Dynamics and Beam Response (open access)

Self-Consistent 3D Modeling of Electron Cloud Dynamics and Beam Response

We present recent advances in the modeling of beam electron-cloud dynamics, including surface effects such as secondary electron emission, gas desorption, etc, and volumetric effects such as ionization of residual gas and charge-exchange reactions. Simulations for the HCX facility with the code WARP/POSINST will be described and their validity demonstrated by benchmarks against measurements. The code models a wide range of physical processes and uses a number of novel techniques, including a large-timestep electron mover that smoothly interpolates between direct orbit calculation and guiding-center drift equations, and a new computational technique, based on a Lorentz transformation to a moving frame, that allows the cost of a fully 3D simulation to be reduced to that of a quasi-static approximation.
Date: April 2, 2007
Creator: Furman, Miguel; Furman, M. A.; Celata, C. M.; Kireeff-Covo, M.; Sonnad, K. G.; Vay, J. L. et al.
Object Type: Article
System: The UNT Digital Library
Effect of Electrode Composition and Microstructure on Impedancemetric Nitric Oxide Sensors based on YSZ Electrolyte (open access)

Effect of Electrode Composition and Microstructure on Impedancemetric Nitric Oxide Sensors based on YSZ Electrolyte

The role of metal (Au, Pt, and Ag) electrodes in YSZ electrolyte-based impedancemetric nitric oxide (NO) sensors is investigated using impedance spectroscopy and equivalent circuit analysis. The test cell consists of a rectangular block of porous YSZ with two metal wire loop electrodes, both exposed to the same atmosphere. Of the electrode materials, only Au was sensitive to changes in NO concentration. The impedance behavior of porous Au electrodes in a slightly different configuration was compared with dense Au electrodes and was also insensitive to NO. Ag showed no sensitivity to either O{sub 2} or NO, and the measured impedances occurred at frequencies > 10 kHz, which are typically associated with ionic conduction in YSZ. Pt and porous Au showed sensitivity to O{sub 2}, which was quantified using power-law exponents that suggest electrochemical rate-determining mechanisms occurring at the triple phase boundary. The behavior of the dense Au suggests different rate-determining processes (e.g., diffusion or adsorption) for the O{sub 2} reaction. Although the exact mechanism is not determined, the composition and microstructure of the metal electrode seem to alter the rate-limiting step of the interfering O{sub 2} reaction. Impedance behavior of the O{sub 2} reaction that is limited by processes occurring …
Date: April 2, 2007
Creator: Woo, L. Y.; Martin, L. P.; Glass, R. S.; Wang, W.; Jung, S.; Gorte, R. J. et al.
Object Type: Article
System: The UNT Digital Library
Sampling and Analysis Instruction for Borehole Sampling at 118-B-1 Burial Ground (open access)

Sampling and Analysis Instruction for Borehole Sampling at 118-B-1 Burial Ground

The Washington Closure Hanford (WCH) Field Remediation Project has removed all of the disposed materials and contaminated soil from the 118-B-1 Burial Ground with the exception of tritium-contaminated soil that is believed to extend from the bottom of the present excavation to groundwater and is believed to contribute to tritium contamination observed at down-gradient monitoring Well 199-B8-6. This sampling and analysis instruction (SAI) provides the requirements for sample collection and laboratory analysis for characterization of the vertical distribution of tritium contamination in the vadose zone soil below the 118-B-1 Burial Ground remedial action excavation.
Date: April 2, 2007
Creator: Thompson, W. S.
Object Type: Report
System: The UNT Digital Library
Stem Cell Research: Federal Research Funding and Oversight (open access)

Stem Cell Research: Federal Research Funding and Oversight

None
Date: April 2, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Alcohol Use Among Youth (open access)

Alcohol Use Among Youth

Alcohol use by persons under age 21 has been identified as a major public health problem. Studies note that it increases the risks for disability, and may be detrimental to the developing brain. Minors who drink are more likely to commit suicide, break the law, or be victims of violence. Alcohol is implicated in nearly one-third of youth traffic fatalities. The total annual cost of underage drinking is estimated at $62 billion. While most laws intended to prevent underage drinking are passed at the state level, there has been legislative activity and interest at the federal level to support states’ efforts to curb the problem. This report describes the extent of underage alcohol use, recent legislative activity on this issue, and various policy implications.
Date: April 2, 2007
Creator: Sommers, Andrew R. & Sundararaman, Ramya
Object Type: Report
System: The UNT Digital Library
Satellite Television: Provisions in SHVERA Affecting Eligibility for Distant and Local Analog Network Signals (open access)

Satellite Television: Provisions in SHVERA Affecting Eligibility for Distant and Local Analog Network Signals

None
Date: April 2, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Navy Nuclear-Powered Surface Ships: Background, Issues, and Options for Congress (open access)

Navy Nuclear-Powered Surface Ships: Background, Issues, and Options for Congress

None
Date: April 2, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Review of Exculsive B to D(*,**)Lnu Decays: Branching Fractions, Form-Factors And |V(Cb| (open access)

Review of Exculsive B to D(*,**)Lnu Decays: Branching Fractions, Form-Factors And |V(Cb|

This paper reviews semileptonic decays of B-mesons to states containing charm mesons, i.e., D, D*, D** and possible non-resonant D{sup (*)}{eta}{pi} states as well. The paper covers measurement of branching fractions, form-factors and, most importantly, the magnitude of the CKM matrix element V{sub cb}. I will not attempt a comprehensive review, but will concentrate on reasonably fresh results and consider mostly exclusive measurements. I will also comment on the consistency of the results and what needs to be done to resolve the apparent conflicts.
Date: April 2, 2007
Creator: Snyder, A. E.
Object Type: Article
System: The UNT Digital Library
Nuclear Analysis for Near Term Fusion Devices (open access)

Nuclear Analysis for Near Term Fusion Devices

A Next Step Options (NSO) study was initiated to consider the logical steps that might be undertaken to restructure the U.S. Fusion Sciences Program. Most of the effort was concentrated on designing the Fusion Ignition Research Experiment (FIRE), which is in the preconceptual design phase. It utilizes 16 cryogenically cooled wedged copper TF coils with beryllium copper in the inner legs and OFHC copper in the outer legs. We provided significant contributions in the areas of neutronics, shielding and activation analyses. The design went through different changes. Early in the year 2002 the baseline design changed from a major radius of 2 m to a major radius of 2.14 m and an aspect ratio of 3.6. In addition the fusion power during the DT pulses changed from 200 MW to 150 MW. We spent significant part of the effort calculating the nuclear performance parameters for the final baseline design. While pulses producing a total of 5 TJ of DT fusion energy and 0.5 TJ of DD fusion energy were considered in the previous designs, a detailed experimental plan was developed that results in higher total fusion energy. We assessed the impact on the peak magnet insulator dose. Multi-dimensional calculations were …
Date: April 2, 2007
Creator: Sawan, M.E.; Kulcinski, G.L. & Henderson, D.L.
Object Type: Report
System: The UNT Digital Library
Optical Klystron Enhancement to SASE X-Ray FELs (open access)

Optical Klystron Enhancement to SASE X-Ray FELs

None
Date: April 2, 2007
Creator: Ding, Y. T.; Emma, P.; Huang, Z. & Kumar, V.
Object Type: Article
System: The UNT Digital Library
Annual Technical Progress Report of Radioisotope Power System Materials Production and Technical Program Tasks for October 1, 2005 through September 30, 2006 (open access)

Annual Technical Progress Report of Radioisotope Power System Materials Production and Technical Program Tasks for October 1, 2005 through September 30, 2006

The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2006. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.
Date: April 2, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
THREE-DIMENSIONAL FIELD MODELS FOR REVERSE BIASED P-N JUNCTIONS. (open access)

THREE-DIMENSIONAL FIELD MODELS FOR REVERSE BIASED P-N JUNCTIONS.

In order to obtain reliable quantitative information on the electrostatic field associated with reverse-biased p-n junctions and on the distribution of dopants, the physics of the so-called ''dead layer'' and the influence of charged oxide layers are of paramount importance. To this purpose, experimental observations near the edge of a TEM sample can be useful. In these conditions, however, phase computations required to interpret the experimental results are very challenging as the problem is intrinsically three-dimensional. In order to cope with this problem, a mixed analytical-numerical approach is presented and discussed.
Date: April 2, 2007
Creator: UBALDI,F.; POZZI, G.; FAZZINI, P.F. & BELEGGIA, M.
Object Type: Article
System: The UNT Digital Library
Intermittent Jet Activity in the Radio Galaxy 4C29.30? (open access)

Intermittent Jet Activity in the Radio Galaxy 4C29.30?

We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large Array (VLA) and the Effelsberg telescope. We report the existence of weak extended emission with an angular size of {approx} 520 arcsec (639 kpc) within which a compact edge-brightened double-lobed source with a size of 29 arcsec (36 kpc) is embedded. We determine the spectrum of the inner double from 240 to 8460 MHz and show that it has a single power-law spectrum with a spectral index is {approx} 0.8. Its spectral age is estimated to be 33 Myr. The extended diffuse emission has a steep spectrum with a spectral index of {approx} 1.3 and a break frequency 240 MHz. The spectral age is {approx}>200 Myr, suggesting that the extended diffuse emission is due to an earlier cycle of activity. We reanalyze archival x-ray data from Chandra and suggest that the x-ray emission from the hotspots consists of a mixture of nonthermal and thermal components, the latter being possibly due to gas which is shock heated by the jets from the host galaxy.
Date: April 2, 2007
Creator: Jamrozy, M.; Konar, C.; Saikia, D. J.; Stawarz, L.; Mack, K. -H. & Siemiginowska, A.
Object Type: Article
System: The UNT Digital Library
Final Report of MBX experiment (open access)

Final Report of MBX experiment

The MBX experiment was built during the grant period. Details can be found in publications about MBX experiment. We created a low density plasma in a mirror configuration and rotated it at supersonic speeds in the theta direction. Under these conditions the plasma presents a high asymmetry in the current, plasma potential and consequently rotation with the voltage applied. We developed a two fluid model to describe the measurements based on a magnetofluid states ansatz. We also observed bistable and multiple states predicted by the two fluid model.
Date: April 2, 2007
Creator: Bengtson, Roger D & Valanju, Prashant
Object Type: Report
System: The UNT Digital Library
Summary Report of Working Group 7: Electromagnetic-Structure Based Accelerators (open access)

Summary Report of Working Group 7: Electromagnetic-Structure Based Accelerators

We detail the most pressing physics and technical issues confronting short-wavelength acceleration. We review new acceleration concepts that are proposed and under development, and recent progress on technical issues such as structure fabrication and material damage. We outline key areas where work is still needed before a reliable assessment of the value of working at wavelengths below 1 cm can be made. Possible ways to enhance collaboration and progress in this important area are also discussed.
Date: April 2, 2007
Creator: Colby, E. & Musumeci, P.
Object Type: Article
System: The UNT Digital Library
Light Nuclei in the Framework of the Symplectic No-Core Shell Model (open access)

Light Nuclei in the Framework of the Symplectic No-Core Shell Model

A symplectic no-core shell model (Sp-NCSM) is constructed with the goal of extending the ab-initio NCSM to include strongly deformed higher-oscillator-shell configurations and to reach heavier nuclei that cannot be studied currently because the spaces encountered are too large to handle, even with the best of modern-day computers. This goal is achieved by integrating two powerful concepts: the ab-initio NCSM with that of the Sp(3,R) {contains} SU(3) group-theoretical approach. The NCSM uses modern realistic nuclear interactions in model spaces that consists of many-body configurations up to a given number of {h_bar}{Upsilon} excitations together with modern high-performance parallel computing techniques. The symplectic theory extends this picture by recognizing that when deformed configurations dominate, which they often do, the model space can be better selected so less relevant low-lying {h_bar}{Upsilon} configurations yield to more relevant high-lying {h_bar}{Upsilon} configurations, ones that respect a near symplectic symmetry found in the Hamiltonian. Results from an application of the Sp-NCSM to light nuclei are compared with those for the NCSM and with experiment.
Date: April 2, 2007
Creator: Draayer, Jerry P.; Dytrych, Tomas; Sviratcheva, Kristina D.; Bahri, Chairul & Vary, James P.
Object Type: Article
System: The UNT Digital Library
Observation of Dust in DIII-D Divertor and SOL by Visible Imaging (open access)

Observation of Dust in DIII-D Divertor and SOL by Visible Imaging

Dust is commonly found in fusion devices. Though generally of no concern in the present day machines, dust may pose serious safety and operational concerns for ITER. Micron-size dust usually dominates the samples collected from tokamaks. During a plasma discharge micron-size dust particles can become highly mobile and travel over distances of a few meters. Once inside the plasma, dust particles heat up to over 3000 K and emit thermal radiation that can be detected by visible imaging techniques. Observations of naturally occurring and artificially introduced dusts have been performed in DIII-D divertor and scrape-off layer (SOL) using standard frame rate CMOS cameras, a gated-intensified CID camera, and a fast-framing CMOS camera. In the first 2-3 plasma discharges after a vent with personnel entry inside the vacuum vessel ('dirty vent') dust levels were quite high with thousands of particles observed in each discharge. Individual particles moving at velocities of up to a few hundred m/s and breakup of larger particles into pieces were observed. After about 15 discharges dust was virtually gone during the stationary portion of a discharge, and appeared at much reduced levels during the plasma initiation and termination phases. After a few days of plasma operations (about …
Date: April 2, 2007
Creator: Rudakov, D. L.; West, W. P.; Groth, M.; Yu, J. H.; Wong, C. C.; Boedo, J. A. et al.
Object Type: Article
System: The UNT Digital Library
Transient Heat Transfer Model for Srs Waste Tank Operations (open access)

Transient Heat Transfer Model for Srs Waste Tank Operations

None
Date: April 2, 2007
Creator: Lee, S. & Richard Dimenna, R.
Object Type: Article
System: The UNT Digital Library
Biodiesel -- Learning from the Lessons of E85 (open access)

Biodiesel -- Learning from the Lessons of E85

None
Date: April 2, 2007
Creator: Brodt-Giles, D.
Object Type: Article
System: The UNT Digital Library
FERMI @ Elettra: a Seeded FEL Facility for EUV And Soft X-Rays (open access)

FERMI @ Elettra: a Seeded FEL Facility for EUV And Soft X-Rays

None
Date: April 2, 2007
Creator: Corlett, J. N.; Doolittle, L. R.; Fawley, W. M.; Lidia, S. M.; Penn, G.; Pogorelov, I. V. et al.
Object Type: Article
System: The UNT Digital Library
Labor Union Recognition Procedures: Use of Secret Ballots and Card Checks (open access)

Labor Union Recognition Procedures: Use of Secret Ballots and Card Checks

This report begins with a summary of legislation that would, if enacted, change existing union recognition procedures. The report then reviews the rights and responsibilities of workers and employers under the National Labor Relations Act (NLRA) and the different ways that workers may form or join a union. The report then examines the potential impact of changes in union recognition procedures. Finally, the report considers whether there is an economic rationale for protecting the rights of workers to organize and bargain collectively.
Date: April 2, 2007
Creator: Mayer, Gerald
Object Type: Report
System: The UNT Digital Library