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An Incompressible Navier-Stokes with Particles Algorithm andParallel Implementation (open access)

An Incompressible Navier-Stokes with Particles Algorithm andParallel Implementation

We present a variation of an adaptive projection method forcomputing solutions to the incompressible Navier-Stokes equations withsuspended particles. To compute the divergence-free component of themomentum forcing due to the particle drag, we employ an approach whichexploits the locality and smoothness of the Laplacian of the projectionoperator applied to the discretized particle drag force. We presentconvergence and performance results to demonstrate the effectiveness ofthis approach.
Date: November 28, 2006
Creator: Martin, Daniel F.; Colella, Phillip & Keen, Noel D.
Object Type: Article
System: The UNT Digital Library
Downhole Fluid Analyzer Development (open access)

Downhole Fluid Analyzer Development

A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.
Date: November 28, 2006
Creator: Turner, Bill
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 506, Ed. 1 Tuesday, November 28, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 506, Ed. 1 Tuesday, November 28, 2006

Free weekly newspaper that includes business and classified advertising.
Date: November 28, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 50, Ed. 1 Tuesday, November 28, 2006 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 50, Ed. 1 Tuesday, November 28, 2006

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: November 28, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Executive Office of the President: An Historical Overview (open access)

The Executive Office of the President: An Historical Overview

This report provides an An Historical Overview about The Executive Office of the President. It consists of a group of federal agencies immediately serving the President.
Date: November 28, 2006
Creator: Relyea, Harold C.
Object Type: Report
System: The UNT Digital Library
Developing New Tools for the in vivo Generation/Screening of Cyclic Peptide Libraries. A New Combinatorial Approach for the Detection of Bacterial Toxin Inhibitors (open access)

Developing New Tools for the in vivo Generation/Screening of Cyclic Peptide Libraries. A New Combinatorial Approach for the Detection of Bacterial Toxin Inhibitors

A new combinatorial approach for the biosynthesis and screening of small drug-like toxin inhibitors inside living cells is presented. This approach has been initially used as proof of principle for finding inhibitors against the LF factor from Bacillus anthracis. Key to our ''living combinatorial'' approach is the use of a living cell as a micro-chemical factory for both synthesis and screening of potential inhibitors for a given molecular recognition event (see Scheme 1). This powerful technique posses the advantage that both processes synthesis and screening happen inside the cell thus accelerating the whole screening/selection process.
Date: November 28, 2006
Creator: Camarero, J A
Object Type: Report
System: The UNT Digital Library
Magnetocentrifugal Winds in 3D: Nonaxisymmetric Steady State (open access)

Magnetocentrifugal Winds in 3D: Nonaxisymmetric Steady State

Outflows can be loaded and accelerated to high speeds along rapidly rotating, open magnetic field lines by centrifugal forces. Whether such magnetocentrifugally driven winds are stable is a longstanding theoretical problem. As a step towards addressing this problem, we perform the first large-scale 3D MHD simulations that extend to a distance {approx} 10{sup 2} times beyond the launching region, starting from steady 2D (axisymmetric) solutions. In an attempt to drive the wind unstable, we increase the mass loading on one half of the launching surface by a factor of {radical}10, and reduce it by the same factor on the other half. The evolution of the perturbed wind is followed numerically. We find no evidence for any rapidly growing instability that could disrupt the wind during the launching and initial phase of propagation, even when the magnetic field of the magnetocentrifugal wind is toroidally dominated all the way to the launching surface. The strongly perturbed wind settles into a new steady state, with a highly asymmetric mass distribution. The distribution of magnetic field strength is, in contrast, much more symmetric. We discuss possible reasons for the apparent stability, including stabilization by an axial poloidal magnetic field, which is required to bend …
Date: November 28, 2006
Creator: Anderson, Jeffrey M.; Li, Zhi-Yun; /Virginia U., Astron. Dept.; Krasnopolsky, Ruben; /Toronto U., Astron. Dept.; Blandford, Roger D. et al.
Object Type: Article
System: The UNT Digital Library
Swift Detects a Remarkable Gamma-Ray Burst, GRB 060614, That Introduces a New Classification Scheme (open access)

Swift Detects a Remarkable Gamma-Ray Burst, GRB 060614, That Introduces a New Classification Scheme

Gamma ray bursts (GRBs) are known to come in two duration classes, separated at {approx}2 s. Long bursts originate from star forming regions in galaxies, have accompanying supernovae (SNe) when near enough to observe and are likely caused by massive-star collapsars. Recent observations show that short bursts originate in regions within their host galaxies with lower star formation rates, consistent with binary neutron star (NS) or NS - black hole (BH) mergers. Moreover, although their hosts are predominantly nearby galaxies, no SNe have been so far associated with short GRBs. We report here on the bright, nearby GRB 060614 that does not fit in either class. Its {approx}102 s duration groups it with long GRBs, while its temporal lag and peak luminosity fall entirely within the short GRB subclass. Moreover, very deep optical observations exclude an accompanying supernova, similar to short GRBs. This combination of a long duration event without accompanying SN poses a challenge to both a collapsar and merging NS interpretation and opens the door on a new GRB classification scheme that straddles both long and short bursts.
Date: November 28, 2006
Creator: Gehrels, Neil; Norris, J.P.; Mangano, V.; Barthelmy, S.D.; Burrows, D.N.; Granot, J. et al.
Object Type: Article
System: The UNT Digital Library
Description of ALARMA: the alarm algorithm developed for the Nuclear Car Wash (open access)

Description of ALARMA: the alarm algorithm developed for the Nuclear Car Wash

The goal of any alarm algorithm should be that it provide the necessary tools to derive confidence limits on whether the existence of fissile materials is present in cargo containers. It should be able to extract these limits from (usually) noisy and/or weak data while maintaining a false alarm rate (FAR) that is economically suitable for port operations. It should also be able to perform its analysis within a reasonably short amount of time (i.e. {approx} seconds). To achieve this, it is essential that the algorithm be able to identify and subtract any interference signature that might otherwise be confused with a fissile signature. Lastly, the algorithm itself should be user-intuitive and user-friendly so that port operators with little or no experience with detection algorithms may use it with relative ease. In support of the Nuclear Car Wash project at Lawrence Livermore Laboratory, we have developed an alarm algorithm that satisfies the above requirements. The description of the this alarm algorithm, dubbed ALARMA, is the purpose of this technical report. The experimental setup of the nuclear car wash has been well documented [1, 2, 3]. The presence of fissile materials is inferred by examining the {beta}-delayed gamma spectrum induced after …
Date: November 28, 2006
Creator: Luu, T; Biltoft, P; Church, J; Descalle, M; Hall, J; Manatt, D et al.
Object Type: Report
System: The UNT Digital Library
SciDAC Visualization and Analytics Center for EnablingTechnology (open access)

SciDAC Visualization and Analytics Center for EnablingTechnology

The SciDAC2 Visualization and Analytics Center for EnablingTechnologies (VACET) began operation on 10/1/2006. This document, dated11/27/2006, is the first version of the VACET project management plan. Itwas requested by and delivered to ASCR/DOE. It outlines the Center'saccomplishments in the first six weeks of operation along with broadobjectives for the upcoming future (12-24 months).
Date: November 28, 2006
Creator: Bethel, E. Wes; Johnson, Chris; Joy, Ken; Ahern, Sean; Pascucci,Valerio; Childs, Hank et al.
Object Type: Article
System: The UNT Digital Library
Time-varying Reeb Graphs: A Topological Framework Supporting the Analysis of Continuous Time-varying Data (open access)

Time-varying Reeb Graphs: A Topological Framework Supporting the Analysis of Continuous Time-varying Data

I present time-varying Reeb graphs as a topological framework to support the analysis of continuous time-varying data. Such data is captured in many studies, including computational fluid dynamics, oceanography, medical imaging, and climate modeling, by measuring physical processes over time, or by modeling and simulating them on a computer. Analysis tools are applied to these data sets by scientists and engineers who seek to understand the underlying physical processes. A popular tool for analyzing scientific datasets is level sets, which are the points in space with a fixed data value s. Displaying level sets allows the user to study their geometry, their topological features such as connected components, handles, and voids, and to study the evolution of these features for varying s. For static data, the Reeb graph encodes the evolution of topological features and compactly represents topological information of all level sets. The Reeb graph essentially contracts each level set component to a point. It can be computed efficiently, and it has several uses: as a succinct summary of the data, as an interface to select meaningful level sets, as a data structure to accelerate level set extraction, and as a guide to remove noise. I extend these uses …
Date: November 28, 2006
Creator: Mascarenhas, A
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Comparative Costs of Flexible Package Cells and Rigid Cells for Lithium-Ionhybrid Electric Vehicle Batteries. (open access)

Comparative Costs of Flexible Package Cells and Rigid Cells for Lithium-Ionhybrid Electric Vehicle Batteries.

We conducted a design study to compare the manufacturing costs at a level of 100,000 hybrid vehicle batteries per year for flexible package (Flex) cells and for rigid aluminum container (Rigid) cells. Initially, the Rigid cells were considered to have welded closures and to be deep-drawn containers of about the same shape as the Flex cells. As the study progressed, the method of fabricating and sealing the Rigid cells was expanded to include lower cost options including double seaming and other mechanically fastened closures with polymer sealants. Both types of batteries were designed with positive electrodes containing Li(Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3})O{sub 2} and graphite negative electrodes. The use of a different combination of lithium-ion electrodes would have little effect on the difference in costs for the two types of cells. We found that 20-Ah cells could be designed with excellent performance and heat rejection capabilities for either type of cell. Many parts in the design of the Flex cells are identical or nearly identical to those of the Rigid Cell, so for these features there would be no difference in the cost of manufacturing the two types of batteries. We judged the performance, size and weight of the batteries to …
Date: November 28, 2006
Creator: Nelson, P. A. & Jansen, A. N.
Object Type: Report
System: The UNT Digital Library
Discovery of TeV Gamma-Ray Emission from the Cygnus Region (open access)

Discovery of TeV Gamma-Ray Emission from the Cygnus Region

The diffuse gamma radiation arising from the interaction of cosmic ray particles with matter and radiation in the Galaxy is one of the few probes available to study the origin of the cosmic rays. Milagro is a water Cherenkov detector that continuously views the entire overhead sky. The large field-of-view combined with the long observation time makes Milagro the most sensitive instrument available for the study of large, low surface brightness sources such as the diffuse gamma radiation arising from interactions of cosmic radiation with interstellar matter. In this paper we present spatial and flux measurements of TeV gamma-ray emission from the Cygnus Region. The TeV image shows at least one new source MGRO J2019+37 as well as correlations with the matter density in the region as would be expected from cosmic-ray proton interactions. However, the TeV gamma-ray flux as measured at {approx}12 TeV from the Cygnus region (after excluding MGRO J2019+37) exceeds that predicted from a conventional model of cosmic ray production and propagation. This observation indicates the existence of either hard-spectrum cosmic-ray sources and/or other sources of TeV gamma rays in the region.
Date: November 28, 2006
Creator: Abdo, A. A.; Allen, B.; Berley, D.; Blaufuss, E.; Casanova, S.; Chen, C. et al.
Object Type: Article
System: The UNT Digital Library
Very High Pressure Single Pulse Shock Tube Studies of Aromatic Species (open access)

Very High Pressure Single Pulse Shock Tube Studies of Aromatic Species

The principal focus of this research program is aimed at understanding the oxidation and pyrolysis chemistry of primary aromatic molecules and radicals with the goal of developing a comprehensive kinetic model at conditions that are relevant to practical combustion devices. A very high pressure single pulse shock tube is used to obtain experimental data over a wide pressure range in the high pressure regime, 5-1000 bars, at pre-flame temperatures for fuel pyrolysis and oxidation over a broad spectrum of equivalence ratios. Stable species sampled from the shock tube are analyzed using standard chromatographic techniques using GC/MS-PDD and GC/TCD-FID. Experimental data from the HPST (stable species profiles) and data from other laboratories (if available) are simulated using kinetic models (if available) to develop a comprehensive model that can describe aromatics oxidation and pyrolysis over a wide range of experimental conditions. The shock tube has been heated (1000C) recently to minimize effects due to condensation of aromatic, polycyclic and other heavy species. Work during this grant period has focused on 7 main areas summarized in the final technical report.
Date: November 28, 2006
Creator: Brezinsky, K.
Object Type: Report
System: The UNT Digital Library
PU IMMOBILIZATION - INDUCTION MELTING ND OFFGAS TESTING (open access)

PU IMMOBILIZATION - INDUCTION MELTING ND OFFGAS TESTING

The Cylindrical Induction Melter (CIM) at the Aiken County Technology Laboratory (ACTL) has been operated by the Savannah River National Laboratory (SRNL) to support the Pu Disposition Conceptual Design (CD-0) development effort. The primary purpose of this report is to summarize the offgas sampling tests conducted in the CIM to capture and analyze the particulate and vapors emitted from lanthanide borosilicate (LaBS) Frit X with HfO{sub 2} as a surrogate for PuO{sub 2} and added impurities. In addition, this report describes several initial tests of the CIM for the vitrification of LaBS Frit X with HfO{sub 2}. The activities required to produce Frit X from batch chemical oxides for subsequent milling to yield glass frit of nominally 20 micron particle size are also discussed. The tests with impurities added showed that alkali salts such as NaCl and KCl were substantially emitted into the offgas system as the salt particulate, HCl, or Cl{sub 2}. Retention of Na and K in the glass were about 80 and 55%, respectively. Chloride retention was about 35%; chloride remaining in the glass was 0.29-0.37 wt%. Based on a material balance, approximately 83% of F fed was retained in the glass at about 0.09 wt % …
Date: November 28, 2006
Creator: Marra, J
Object Type: Report
System: The UNT Digital Library
The Aqueous Thermodynamics and Complexation Reactions of Anionic Silica and Uranium Species to High Concentration (open access)

The Aqueous Thermodynamics and Complexation Reactions of Anionic Silica and Uranium Species to High Concentration

During this contract period, a number of papers were published. The papers prior to this report have been reported in earlier annual reports. This final report covers the 2005 & 2006 publications which have been published as well as the last few which have been submitted, but are still under review for acceptance for publication. The titles and Abstract of the papers are presented in Section A, and the full published papers in Section B.
Date: November 28, 2006
Creator: Choppin, Gregory R.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 3, Ed. 1 Tuesday, November 28, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 3, Ed. 1 Tuesday, November 28, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 28, 2006
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Referee's report on Blast-wave diagnosis of self-focusing of an intense laser pulse in a cluster medium, by Symes et al. (open access)

Referee's report on Blast-wave diagnosis of self-focusing of an intense laser pulse in a cluster medium, by Symes et al.

None
Date: November 28, 2006
Creator: Edwards, M J
Object Type: Report
System: The UNT Digital Library
Prison Litigation Reform Act in the Supreme Court’s 2006 Term (open access)

Prison Litigation Reform Act in the Supreme Court’s 2006 Term

None
Date: November 28, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Lebanon (open access)

Lebanon

None
Date: November 28, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Weapons of Mass Destruction: Trade Between North Korea and Pakistan (open access)

Weapons of Mass Destruction: Trade Between North Korea and Pakistan

In October 2002, the United States confronted North Korea about its alleged clandestine uranium enrichment program. Soon after, the Agreed Framework collapsed, North Korea expelled international inspectors, and withdrew from the Nuclear Nonproliferation Treaty (NPT). U.S. intelligence officials claimed Pakistan was a key supplier of uranium enrichment technology to North Korea, and some media reports suggested that Pakistan had exchanged centrifuge enrichment technology for North Korean help in developing longer range missiles.
Date: November 28, 2006
Creator: Squassoni, Sharon A.
Object Type: Report
System: The UNT Digital Library

Ensemble: 2006-11-28 – Men's Chorus and Women's Chorus

Access: Use of this item is restricted to the UNT Community
Women's and Men's Chorus concert performed in UNT College of Music Winspear Performance Hall.
Date: November 28, 2006
Creator: University of North Texas. Women's Chorus.
Object Type: Sound
System: The UNT Digital Library
Galactic Variable Sky with EGRET and GLAST (open access)

Galactic Variable Sky with EGRET and GLAST

The characteristics of the largely-unidentified Galactic sources of gamma rays that were detected by EGRET are reviewed. Proposed source populations that may have the correct spatial, spectral, luminosity, and variability properties to be the origins of the EGRET sources are also presented. Finally, the prospects for studying Galactic gamma-ray sources with the GLAST LAT are reviewed.
Date: November 28, 2006
Creator: Digel, S.W.
Object Type: Article
System: The UNT Digital Library
Search for the Baryon and Lepton Number Violating Decays tau to Lambda h (open access)

Search for the Baryon and Lepton Number Violating Decays tau to Lambda h

The authors have searched for the violation of baryon number B and lepton number L in the (B-L)-conserving modes {tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -} as well as the (B-L)-violating modes {tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {Lambda}{sup 0}K{sup -} using 237 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They do not observe any signal and determine preliminary upper limits on the branching fractions {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -}) < 5.9 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -}) < 5.8 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -}) < 7.2 x 10{sup -8}, and {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}K{sup -}) < 15 x 10{sup -8} at 90% confidence level.
Date: November 28, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library