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Robust Nuclear Earth Penetrator Budget Request and Plan, FY2005-FY2009 (open access)

Robust Nuclear Earth Penetrator Budget Request and Plan, FY2005-FY2009

None
Date: April 9, 2004
Creator: Medalia, Jonathan
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 29, Number 15, Pages 3541-3718, April 9, 2004 (open access)

Texas Register, Volume 29, Number 15, Pages 3541-3718, April 9, 2004

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: April 9, 2004
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 88, No. 103, Ed. 1 Friday, April 9, 2004 (open access)

North Texas Daily (Denton, Tex.), Vol. 88, No. 103, Ed. 1 Friday, April 9, 2004

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: April 9, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
[Funeral Program for Minerva Louise Jones Watson, April 9, 2004] (open access)

[Funeral Program for Minerva Louise Jones Watson, April 9, 2004]

Funeral program for Mrs. Minerva Louise James Watson, born January 1, 1921 and died April 3, 2004. The funeral was held April 9, 2004 at Mt. Zion First Baptist Church, officiated by Rev. Kenneth A. Allen, Sr. Funeral arrangements were made through Carter-Taylor-Williams Mortuary, and she was buried in Southern Memorial Park in San Antonio, Texas.
Date: April 9, 2004
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
The Rice Thresher, Vol. 91, No. 26, Ed. 1 Friday, April 9, 2004 (open access)

The Rice Thresher, Vol. 91, No. 26, Ed. 1 Friday, April 9, 2004

A weekly student newspaper from the Rice University in Houston, Texas that includes campus news and commentaries along with advertising.
Date: April 9, 2004
Creator: Yardley, Jonathan
Object Type: Newspaper
System: The Portal to Texas History
Military Operations: DOD Needs to Provide Central Direction for Supporting Coalition Liaison Officers (open access)

Military Operations: DOD Needs to Provide Central Direction for Supporting Coalition Liaison Officers

A letter report issued by the General Accounting Office with an abstract that begins "In the National Defense Authorization Act for Fiscal Year 2003, Congress authorized the Secretary of Defense to provide administrative services and support to foreign coalition liaison officers temporarily assigned to the headquarters of a combatant command or any of its subordinate commands. Congress required GAO to assess the implementation of this legislation. Specifically, GAO's objectives were to determine (1) what guidance the Department of Defense (DOD) has provided on the implementation of this legislation, (2) the extent to which the commands are aware of and are using this legislation, and (3) the level of support being provided by commands using this legislation and the benefits derived from it."
Date: April 9, 2004
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 20, No. 48, Ed. 1 Friday, April 9, 2004 (open access)

Dallas Voice (Dallas, Tex.), Vol. 20, No. 48, Ed. 1 Friday, April 9, 2004

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: April 9, 2004
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
A tool for the quantitative spatial analysis of mammary gland epithelium (open access)

A tool for the quantitative spatial analysis of mammary gland epithelium

In this paper we present a method for the spatial analysis of complex cellular systems based on a multiscale study of neighborhood relationships. A function to measure those relationships, M, is introduced. The refined Relative Neighborhood Graph is then presented as a method to establish vicinity relationships within layered cellular structures, and particularized to epithelial cell nuclei in the mammary gland. Finally, the method is illustrated with two examples that show interactions within one population of epithelial cells and between two different populations.
Date: April 9, 2004
Creator: Ortiz de Solorzano, Carlos & Fernandez-Gonzalez, Rodrigo
Object Type: Article
System: The UNT Digital Library
The QCD/SM working group: Summary report (open access)

The QCD/SM working group: Summary report

Among the many physics processes at TeV hadron colliders, we look most eagerly for those that display signs of the Higgs boson or of new physics. We do so however amid an abundance of processes that proceed via Standard Model (SM) and in particular Quantum Chromodynamics (QCD) interactions, and that are interesting in their own right. Good knowledge of these processes is required to help us distinguish the new from the known. Their theoretical and experimental study teaches us at the same time more about QCD/SM dynamics, and thereby enables us to further improve such distinctions. This is important because it is becoming increasingly clear that the success of finding and exploring Higgs boson physics or other New Physics at the Tevatron and LHC will depend significantly on precise understanding of QCD/SM effects for many observables. To improve predictions and deepen the study of QCD/SM signals and backgrounds was therefore the ambition for our QCD/SM working group at this Les Houches workshop. Members of the working group made significant progress towards this on a number of fronts. A variety of tools were further developed, from methods to perform higher order perturbative calculations or various types of resummation, to improvements in …
Date: April 9, 2004
Creator: Dobbs, Matt; Frixione, S.; Laenen, E.; De Roeck, A.; Tollefson, K.; Andersen, J. et al.
Object Type: Article
System: The UNT Digital Library
Optimization of Outer Poloidal Field (PF) Coil Configurations for Inductive PF Coil-only Plasma Start-up on Spherical Tori (open access)

Optimization of Outer Poloidal Field (PF) Coil Configurations for Inductive PF Coil-only Plasma Start-up on Spherical Tori

The elimination of in-board ohmic heating solenoid is required for the spherical torus (ST) to function as an attractive fusion power plant. An in-board ohmic solenoid, along with the shielding needed for its insulation, increases the size and, hence, the cost of the plant. Here, we investigate using static as well as dynamic codes in ST geometries a solenoid-free start-up concept utilizing a set of out-board poloidal field coils. By using the static code, an optimization of coil positions as well as coil currents was performed to demonstrate that it is indeed possible to create a high quality multi-pole field null region while retaining significant flux (volt-seconds) needed for the subsequent current ramp-up. With the dynamic code that includes the effect of vacuum vessel eddy currents, we then showed that it is possible to maintain a large size field null region for several milliseconds in which sufficient ionization avalanche can develop in the applied toroidal electric field. Under the magnetic geometry typical of a next generation spherical torus experiment, it is shown that the well-known plasma breakdown conditions for conventional ohmic solenoid start-up of E(sub)TB(sub)T/B(sub)P {approx} (0.1-1) kV/m with V(sub)loop {approx} 6 V can be readily met while retaining significant …
Date: April 9, 2004
Creator: Choe, Wonho; Kim, Jayhyun & Ono, Masayuki
Object Type: Report
System: The UNT Digital Library
Weibel and Two-Stream Instabilities for Intense Charged Particle Beam Propagation through Neutralizing Background Plasma (open access)

Weibel and Two-Stream Instabilities for Intense Charged Particle Beam Propagation through Neutralizing Background Plasma

Properties of the multi-species electromagnetic Weibel and electrostatic two-stream instabilities are investigated for an intense ion beam propagating through background plasma. Assuming that the background plasma electrons provide complete charge and current neutralization, detailed linear stability properties are calculated within the framework of a macroscopic cold-fluid model for a wide range of system parameters.
Date: April 9, 2004
Creator: Davidson, Ronald C.; Kaganovich, Igor & Startsev, Edward A.
Object Type: Report
System: The UNT Digital Library
Implications of beam phase and RFSUM measured near transition (open access)

Implications of beam phase and RFSUM measured near transition

Understanding the transition-crossing process is crucial for improving Booster performance at high intensity. The synchronous phase appears to drop toward 90{sup o} right after transition regardless of beam intensity, more so at higher beam intensity. The implication is that the effective rf voltage (RFSUM) will run into a limit right after transition when the synchronous phase reaches 90{sup o} for high intensity beam. A reduction in RFSUM is also observed at the same time. Solutions, such as raising the rf voltage during the transition period or controlling the RFSUM reduction by increasing longitudinal emittance before transition, are potentially important for high intensity operation.
Date: April 9, 2004
Creator: Yang, Xi & MacLachlan, James
Object Type: Report
System: The UNT Digital Library
Analytical Solutions for the Nonlinear Longitudinal Drift Compression (Expansion) of Intense Charged Particle Beams (open access)

Analytical Solutions for the Nonlinear Longitudinal Drift Compression (Expansion) of Intense Charged Particle Beams

To achieve high focal spot intensities in heavy ion fusion, the ion beam must be compressed longitudinally by factors of ten to one hundred before it is focused onto the target. The longitudinal compression is achieved by imposing an initial velocity profile tilt on the drifting beam. In this paper, the problem of longitudinal drift compression of intense charged particle beams is solved analytically for the two important cases corresponding to a cold beam, and a pressure-dominated beam, using a one-dimensional warm-fluid model describing the longitudinal beam dynamics.
Date: April 9, 2004
Creator: Startsev, Edward A. & Davidson, Ronald C.
Object Type: Report
System: The UNT Digital Library
Coherent synchrotron radiation and bunch stability in a compactstorage ring (open access)

Coherent synchrotron radiation and bunch stability in a compactstorage ring

We examine the effect of the collective force due to coherent synchrotron radiation (CSR) in an electron storage ring with small bending radius. In a computation based on time-domain integration of the nonlinear Vlasov equation, we find the threshold current for a longitudinal microwave instability induced by CSR alone. The model accounts for suppression of radiation at long wave lengths due to shielding by the vacuum chamber. In a calculation just above threshold, small ripples in the charge distribution build up over a fraction of a synchrotron period, but then die out to yield a relatively smooth but altered distribution with eventual oscillations in bunch length. The instability evolves from small noise on an initial smooth bunch of r.m.s.length much greater than the shielding cutoff. The paper includes a derivation and extensive analysis of the complete impedance function Z for synchrotron radiation with parallel plate shielding. We find corrections to the lowest approximation to the coherent force which involve ''off-diagonal'' values of Z, that is, fields with phase velocity not equal to the particle velocity.
Date: April 9, 2004
Creator: Venturini, Marco; Warnock, Robert; Ruth, Ronald & Ellison, James A.
Object Type: Article
System: The UNT Digital Library
Determination of Unknown Neutron Cross Sections for the Production of Medical Isotopes (open access)

Determination of Unknown Neutron Cross Sections for the Production of Medical Isotopes

Calculational assessment and experimental verification of certain neutron cross sections that are related to widely needed new medical isotopes. Experiments were performed at the Oregon State University TRIGA Reactor and the High Flux Irradiation Reactor at Oak Ridge National Laboratory.
Date: April 9, 2004
Creator: Binney, Stephen E.
Object Type: Report
System: The UNT Digital Library
Electric Utility Infrastructure Vulnerabilities: Transformers, Towers, and Terrorism (open access)

Electric Utility Infrastructure Vulnerabilities: Transformers, Towers, and Terrorism

None
Date: April 9, 2004
Creator: Abel, Amy; Parfomak, Paul W. & Shea, Dana A.
Object Type: Report
System: The UNT Digital Library
H.R. 3108: The Pension Funding Equity Act (open access)

H.R. 3108: The Pension Funding Equity Act

None
Date: April 9, 2004
Creator: Purcell, Patrick & Graney, Paul
Object Type: Report
System: The UNT Digital Library
Progress on the Development of a Single Line of Sight X-ray Framing Camera (open access)

Progress on the Development of a Single Line of Sight X-ray Framing Camera

High-speed micro-strip micro-channel plate (MCP) x-ray framing cameras are a well established diagnostic for laser plasma experiments. Each frame acquired with these devices requires a separate image, and with most reasonable x-ray optics, a separate line of sight, causing potential parallax problems. Gated image tubes have a single line of sight capability, but the conventional designs have not been effectively extended to the short gating times of the micro-strip-line MCP camera. A hybrid camera combining image tube and micro-strip-line MCP technology has been under development at LLNL in collaboration with UR/LLE, and KENTECH Instruments. The key feature of this single line of sight (SLOS) hybrid image tube is a deflection assembly that continuously divides the electrons from a single photocathode x-ray image into a set of four electron images. Temporal gating of these images is carried out using a microstripline microchannel plate framing camera module positioned at the image plane of the electron tube. Characterization measurements performed using both X-rays from a Manson source and from laser generated plasmas, will be presented. Some implementation improvements will be discussed. The results will be compared to simulations carried out using the charged particle optics code SIMION. Various dissector designs were simulated in …
Date: April 9, 2004
Creator: Bradley, D. K.; Holder, J. P.; Damian, C. M.; Piston, K. W.; Bell, P. M.; Dymoke-Bradshaw, A. K. L. et al.
Object Type: Article
System: The UNT Digital Library
Nanosecond Gating of Microstripline Microchannel Plate Framing Cameras: Characterization and Simulation (open access)

Nanosecond Gating of Microstripline Microchannel Plate Framing Cameras: Characterization and Simulation

The soft x-ray microstripline microchannel plate (MCP) framing camera has become one of the workhorses of ICF diagnostics. Much progress has been made in making these diagnostics work well with gate times of 100 ps and below. Often weak input signal or source timing uncertainties dictate a requirement for longer gate times, preferably in the same instrument that also has fast gating capability. The large power-law dependence of MCP gain on applied voltage is useful in shortening the gating time of the microstripline camera. However, this sensitivity leads to tight constraints on the shape of the long duration electrical pulses that are needed to drive the MCP to produce experimentally desirable optical gating profiles. Simple modeling and measurements are used to better understand the character of the voltage pulses needed to achieve optical gate widths between 500 ps and {approx}2 ns.
Date: April 9, 2004
Creator: Holder, J. P.; Hargrove, D. R.; Sibernagel, C. T.; Perry, T. S.; Bradley, D. K. & Bell, P. M.
Object Type: Article
System: The UNT Digital Library
Adaptive Algebraic Multigrid Methods (open access)

Adaptive Algebraic Multigrid Methods

Our ability to simulate physical processes numerically is constrained by our ability to solve the resulting linear systems, prompting substantial research into the development of multiscale iterative methods capable of solving these linear systems with an optimal amount of effort. Overcoming the limitations of geometric multigrid methods to simple geometries and differential equations, algebraic multigrid methods construct the multigrid hierarchy based only on the given matrix. While this allows for efficient black-box solution of the linear systems associated with discretizations of many elliptic differential equations, it also results in a lack of robustness due to assumptions made on the near-null spaces of these matrices. This paper introduces an extension to algebraic multigrid methods that removes the need to make such assumptions by utilizing an adaptive process. The principles which guide the adaptivity are highlighted, as well as their application to algebraic multigrid solution of certain symmetric positive-definite linear systems.
Date: April 9, 2004
Creator: Brezina, M; Falgout, R; MacLachlan, S; Manteuffel, T; McCormick, S & Ruge, J
Object Type: Article
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 109, No. 24, Ed. 1 Friday, April 9, 2004 (open access)

The Clifton Record (Clifton, Tex.), Vol. 109, No. 24, Ed. 1 Friday, April 9, 2004

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: April 9, 2004
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
The Harper News (Harper, Tex.), Vol. 1, No. 12, Ed. 1 Friday, April 9, 2004 (open access)

The Harper News (Harper, Tex.), Vol. 1, No. 12, Ed. 1 Friday, April 9, 2004

Biweekly newspaper from Harper, Texas that includes community news along with advertising.
Date: April 9, 2004
Creator: Stevens, Martha
Object Type: Newspaper
System: The Portal to Texas History
Oral History Interview with R. C. Nieto, April 9, 2004 transcript

Oral History Interview with R. C. Nieto, April 9, 2004

Interview with R. C. Nieto, a combat engineer in the US Army during WWII and the Korean War. He answers questions about his life before the military and his experiences overseas.
Date: April 9, 2004
Creator: Coy, Marisa E. & Nieto, R. C.
Object Type: Sound
System: The Portal to Texas History
Large Eddy Simulation of Turbulent Flow and Dispersion in Urban Areas and Forest Canopies (open access)

Large Eddy Simulation of Turbulent Flow and Dispersion in Urban Areas and Forest Canopies

Under the sponsorship of the U.S. DOE and DHS, we have developed a CFD model for simulating flow and dispersion of chemical and biological agents released in the urban environment. Our model, FEM3MP (Chan and Stevens, 2000), is based on solving the three-dimensional, time-dependent, incompressible Navier-Stokes equations on massively parallel computer platforms. The model uses the finite element method for accurate representation of complex building shapes and variable terrain, together with a semi-implicit projection method and modern iterative solvers for efficient time integration (Gresho and Chan, 1998). Physical processes treated include turbulence modeling via the RANS (Reynolds Averaged Navier-Stokes) and LES (Large Eddy Simulation) approaches, atmospheric stability, aerosols, UV radiation decay, surface energy budget, and vegetative canopies, etc. Predictions from our model are continuously being verified and validated against data from wind tunnel (Chan and Stevens, 2000; Chan, et al., 2001) and field experiments (Chan, et al., 2002, 2003; Lee, et al., 2002; Humphreys, et al., 2003; and Calhoun, et al., 2004). Discussed below are several examples to illustrate the use of FEM3MP in simulating flow and dispersion in urban areas and forest canopies, with model results compared against available field measurements.
Date: April 9, 2004
Creator: Chan, Stevens T.
Object Type: Article
System: The UNT Digital Library