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Military Operations: High-Level DOD Action Needed to Address Long-standing Problems with Management and Oversight of Contractors Supporting Deployed Forces (open access)

Military Operations: High-Level DOD Action Needed to Address Long-standing Problems with Management and Oversight of Contractors Supporting Deployed Forces

A letter report issued by the Government Accountability Office with an abstract that begins "Prior GAO reports have identified problems with the Department of Defense's (DOD) management and oversight of contractors supporting deployed forces. GAO issued its first comprehensive report examining these problems in June 2003. Because of the broad congressional interest in U.S. military operations in Iraq and DOD's increasing use of contractors to support U.S. forces in Iraq, GAO initiated this follow-on review under the Comptroller General's statutory authority. Specifically, GAO's objective was to determine the extent to which DOD has improved its management and oversight of contractors supporting deployed forces since our 2003 report. GAO reviewed DOD policies and interviewed military and contractor officials both at deployed locations and in the United States."
Date: December 18, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Trade Adjustment Assistance: New Program for Farmers Provides Some Assistance, but Has Had Limited Participation and Low Program Expenditures (open access)

Trade Adjustment Assistance: New Program for Farmers Provides Some Assistance, but Has Had Limited Participation and Low Program Expenditures

A letter report issued by the Government Accountability Office with an abstract that begins "While tens of thousands of manufacturing workers have received services through the Trade Adjustment Assistance (TAA) program, until 2002, farmers and fishermen impacted by imports did not have access to similar assistance. The Trade Act of 2002 (Trade Act) established a new program, TAA for Farmers, administered by the U.S. Department of Agriculture (USDA) to provide technical assistance, a cash payment of up to $10,000 a year, and access to Department of Labor (Labor) training and reemployment services for farmers and fishermen who face significant price declines due to increased imports. The Trade Act provides for up to $90 million each year through fiscal year 2007 for the costs to carry out the program. Trade Act programs are due for reauthorization in 2007. To be eligible for benefits, farmers and fishermen--called producers--must complete a two-part process each year. First, a group of producers of a commodity must submit a petition to USDA on behalf of all producers in one or more states. The petition must demonstrate that the price of the commodity for the most recent marketing year declined by at least 20 percent from the …
Date: December 18, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Reconstruction and Visualization of Fiber and Laminar Structure inthe Normal Human Heart from Ex Vivo DTMRI Data (open access)

Reconstruction and Visualization of Fiber and Laminar Structure inthe Normal Human Heart from Ex Vivo DTMRI Data

Background - The human heart is composed of a helicalnetwork of muscle fibers. These fibers are organized to form sheets thatare separated by cleavage surfaces. This complex structure of fibers andsheets is responsible for the orthotropic mechanical properties ofcardiac muscle. The understanding of the configuration of the 3D fiberand sheet structure is important for modeling the mechanical andelectrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling aftermyocardial infarction.Methods - Anisotropic least square filteringfollowed by fiber and sheet tracking techniques were applied to DiffusionTensor Magnetic Resonance Imaging (DTMRI) data of the excised humanheart. The fiber configuration was visualized by using thin tubes toincrease 3-dimensional visual perception of the complex structure. Thesheet structures were reconstructed from the DTMRI data, obtainingsurfaces that span the wall from the endo- to the epicardium. Allvisualizations were performed using the high-quality ray-tracing softwarePOV-Ray. Results - The fibers are shown to lie in sheets that haveconcave or convex transmural structure which correspond to histologicalstudies published in the literature. The fiber angles varied depending onthe position between the epi- and endocardium. The sheets had a complexstructure that depended on the location within the myocardium. In theapex region the sheets had …
Date: December 18, 2006
Creator: Rohmer, Damien; Sitek, Arkadiusz & Gullberg, Grant T.
Object Type: Article
System: The UNT Digital Library
Performance of a High Resolution Cavity Beam Position Monitor System (open access)

Performance of a High Resolution Cavity Beam Position Monitor System

It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than one nanometer. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 {micro}rad over a dynamic range of approximately {+-} 20 {micro}m.
Date: December 18, 2006
Creator: Walston, S.; Boogert, S.; Chung, C.; Fitsos, P.; Frisch, J.; Gronberg, J. et al.
Object Type: Article
System: The UNT Digital Library
CH Packaging Operations Manual (open access)

CH Packaging Operations Manual

Introduction - This procedure provides instructions forassembling the following CH packaging payload: Drum payload assembly Standard Waste Box (SWB) assembly Ten-Drum Overpack (TDOP)
Date: December 18, 2006
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
Balkan Cooperation on War Crimes Issues (open access)

Balkan Cooperation on War Crimes Issues

This report discusses Balkan Cooperation on War Crimes Issues.
Date: December 18, 2006
Creator: Kim, Julie
Object Type: Report
System: The UNT Digital Library
Upper Mississippi River-Illinois Waterway Investments: Legislation in the 109th Congress (open access)

Upper Mississippi River-Illinois Waterway Investments: Legislation in the 109th Congress

None
Date: December 18, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Endangered Species Act and Claims of Property Rights “Takings” (open access)

The Endangered Species Act and Claims of Property Rights “Takings”

None
Date: December 18, 2006
Creator: Meltz, Robert
Object Type: Report
System: The UNT Digital Library
Institutional Computing Executive Group Review of Multi-programmatic & Institutional Computing, Fiscal Year 2005 and 2006 (open access)

Institutional Computing Executive Group Review of Multi-programmatic & Institutional Computing, Fiscal Year 2005 and 2006

The Institutional Computing Executive Group (ICEG) review of FY05-06 Multiprogrammatic and Institutional Computing (M and IC) activities is presented in the attached report. In summary, we find that the M and IC staff does an outstanding job of acquiring and supporting a wide range of institutional computing resources to meet the programmatic and scientific goals of LLNL. The responsiveness and high quality of support given to users and the programs investing in M and IC reflects the dedication and skill of the M and IC staff. M and IC has successfully managed serial capacity, parallel capacity, and capability computing resources. Serial capacity computing supports a wide range of scientific projects which require access to a few high performance processors within a shared memory computer. Parallel capacity computing supports scientific projects that require a moderate number of processors (up to roughly 1000) on a parallel computer. Capability computing supports parallel jobs that push the limits of simulation science. M and IC has worked closely with Stockpile Stewardship, and together they have made LLNL a premier institution for computational and simulation science. Such a standing is vital to the continued success of laboratory science programs and to the recruitment and retention of …
Date: December 18, 2006
Creator: Langer, S.; Rotman, D.; Schwegler, E.; Folta, P.; Gee, R. & White, D.
Object Type: Report
System: The UNT Digital Library
Nb3Sn for Radio Frequency Cavities (open access)

Nb3Sn for Radio Frequency Cavities

In this article, the suitability of Nb3Sn to improve theperformance of superconducting Radio-Frequency (RF)cavities is discussed.The use of Nb3Sn in RF cavitiesis recognized as an enabling technology toretain a veryhigh cavity quality factor (Q0) at 4.2 K and tosignificantly improve the cavity accelerating efficiency per unitlength(Eacc). This potential arises through the fundamental properties ofNb3Sn. The properties that are extensively characterized in theliterature are, however, mainly related to improvements in currentcarrying capacity (Jc) in the vortex state. Much less is available forthe Meissner state, which is of key importance to cavities. Relevantdata, available for the Meissner state is summarized, and it is shown howthis already validates the use of Nb3Sn. In addition, missing knowledgeis highlighted and suggestions are given for further Meissner statespecific research.
Date: December 18, 2006
Creator: Godeke, A.
Object Type: Article
System: The UNT Digital Library
MODELING OF THE SUB-SUFACE REDUCING ENVIRONMENT OF THE Z-AREA SALTSTONE DISPOSAL FACILITY AT THE SAVANNAH RIVER SITE (open access)

MODELING OF THE SUB-SUFACE REDUCING ENVIRONMENT OF THE Z-AREA SALTSTONE DISPOSAL FACILITY AT THE SAVANNAH RIVER SITE

Low-level radioactive liquid wastes at the U.S. Department of Energy Savannah River Site are treated by mixing the wastes with Saltstone grout to generate the Saltstone waste form that is poured into the concrete vaults for long-term disposal. The formula for Saltstone includes {approx}25 wt% slag to create a reducing environment for mitigating the sub-surface transport of several radionuclides, including Tc-99. A two-dimensional reactive transport model was developed to estimate how long the Z-Area Saltstone will maintain a reducing environment, and therefore its ability to request Tc-99. The model predicted that {approx}16% of the Saltstone reduction capacity would be consumed after 213,000 years. Independent calculations published by other researchers yielded nearly identical results. The general modeling approach and the study results are presented in this paper.
Date: December 18, 2006
Creator: Hang, T & Daniel Kaplan, D
Object Type: Article
System: The UNT Digital Library
Simple Common Plane contact algorithm for explicit FE/FD methods (open access)

Simple Common Plane contact algorithm for explicit FE/FD methods

Common-plane (CP) algorithm is widely used in Discrete Element Method (DEM) to model contact forces between interacting particles or blocks. A new simple contact algorithm is proposed to model contacts in FE/FD methods which is similar to the CP algorithm. The CP is defined as a plane separating interacting faces of FE/FD mesh instead of blocks or particles used in the original CP method. The new method does not require iterations even for very stiff contacts. It is very robust and easy to implement both in 2D and 3D parallel codes.
Date: December 18, 2006
Creator: Vorobiev, O
Object Type: Report
System: The UNT Digital Library
The Inhibiting Bisection Problem (open access)

The Inhibiting Bisection Problem

Given a graph where each vertex is assigned a generation orconsumption volume, we try to bisect the graph so that each part has asignificant generation/consumption mismatch, and the cutsize of thebisection is small. Our motivation comes from the vulnerability analysisof distribution systems such as the electric power system. We show thatthe constrained version of the problem, where we place either the cutsizeor the mismatch significance as a constraint and optimize the other, isNP-complete, and provide an integer programming formulation. We alsopropose an alternative relaxed formulation, which can trade-off betweenthe two objectives and show that the alternative formulation of theproblem can be solved in polynomial time by a maximum flow solver. Ourexperiments with benchmark electric power systems validate theeffectiveness of our methods.
Date: December 18, 2006
Creator: Pinar, Ali; Fogel, Yonatan & Lesieutre, Bernard
Object Type: Article
System: The UNT Digital Library
UNIQUE DESCRIPTION FOR SINGLE TRANSVERSE SPIN ASYMMETRIES IN DIS AND HADRONIC COLLISIONS. (open access)

UNIQUE DESCRIPTION FOR SINGLE TRANSVERSE SPIN ASYMMETRIES IN DIS AND HADRONIC COLLISIONS.

We derive a unique formula for the single-transverse-spin asymmetry in semi-inclusive hadron production in deep inelastic scattering, valid for all transverse momentum region. Based on this, we further study the integrated asymmetry weighted with transverse-momentum. They can be evaluated in terms of the twist-three quark-gluon correlation functions, which are responsible for the single spin asymmetry in single inclusive hadron production in hadronic collisions. By using the fitted twist-three functions from the hadronic collision data, we find a consistent description for SSAs in deep inelastic scattering. This demonstrates that we have a unique picture for SSAs in these two processes, and shall provide important guidelines for future studies.
Date: December 18, 2006
Creator: YUAN, F.
Object Type: Article
System: The UNT Digital Library
Coupled In-Rock and In-Drift Hydrothermal Model Stuudy For Yucca Mountain (open access)

Coupled In-Rock and In-Drift Hydrothermal Model Stuudy For Yucca Mountain

A thermal-hydrologic-natural-ventilation model is configured for simulating temperature, humidity, and condensate distributions in the coupled domains of the in-drift airspace and the near-field rockmass in the proposed Yucca Mountain repository. The multi-physics problem is solved with MULTIFLUX in which a lumped-parameter computational fluid dynamics model is iterated with TOUGH2. The solution includes natural convection, conduction, and radiation for heat as well as moisture convection and diffusion for moisture transport with half waste package scale details in the drift, and mountain-scale heat and moisture transport in the porous and fractured rock-mass. The method provides fast convergence on a personal computer computational platform. Numerical examples and comparison with a TOUGH2 based, integrated model are presented.
Date: December 18, 2006
Creator: Danko, G.; Birkholzer, J. & Bahrami, D.
Object Type: Article
System: The UNT Digital Library
Turn-by-Turn Imaging of the Transverse Beam Profile in PEP-II (open access)

Turn-by-Turn Imaging of the Transverse Beam Profile in PEP-II

During injection or instability, the transverse profile of an individual bunch in a storage ring can change significantly in a few turns. However, most synchrotron-light imaging techniques are not designed for this time scale. We have developed a novel diagnostic that enhances the utility of a fast gated camera by adding, inexpensively, some features of a dual-axis streak camera, in order to watch the turn-by-turn evolution of the transverse profile, in both x and y. The beam's elliptical profile is reshaped using cylindrical lenses to form a tall and narrow ellipse--essentially the projection of the full ellipse onto one transverse axis. We do this projection twice, by splitting the beam into two paths at different heights, and rotating the ellipse by 90{sup o} on one path. A rapidly rotating mirror scans these vertical ''pencils'' of light horizontally across the photocathode of the camera, which is gated for 3 ns on every Nth ring turn. A single readout of the camera captures 100 images, looking like a stroboscopic photograph of a moving object. We have observed the capture of injected charge into a bunch and the rapid change of beam size at the onset of a fast instability.
Date: December 18, 2006
Creator: Fisher, Alan A. & Petree, Mark
Object Type: Article
System: The UNT Digital Library
A Review of X-ray Free-Electron Laser Theory (open access)

A Review of X-ray Free-Electron Laser Theory

High-gain free-electron lasers (FELs) are being developed as extremely bright sources for a next-generation x-ray facility. In this paper, we review the basic theory of the startup, the exponential growth, and the saturation of the high-gain process, emphasizing the self-amplified spontaneous emission (SASE). The radiation characteristics of an x-ray FEL, including its transverse coherence, temporal characteristics, and harmonic content, are discussed. FEL performance in the presence of machine errors and undulator wakefields is examined. Various enhancement schemes through seeding and beam manipulations are summarized.
Date: December 18, 2006
Creator: Huang, Zhirong & Kim, Kwang-Je
Object Type: Article
System: The UNT Digital Library
Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders (open access)

Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders

We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures.
Date: December 18, 2006
Creator: Jones, R. M.; Adolphsen, C. E.; Wang, J. W. & Li, Z.
Object Type: Article
System: The UNT Digital Library
Frequency content of current pulses in slapper detonator bridges (open access)

Frequency content of current pulses in slapper detonator bridges

DFT amplitudes are obtained for digital current pulse files. The frequency content of slapper detonator bridge current pulses is obtained. The frequencies are confined well within the passband of the CVR used to sample them.
Date: December 18, 2006
Creator: Carpenter, K. H.
Object Type: Report
System: The UNT Digital Library
Roles of Oxygen and Water Vapor in the Oxidation of Halogen Terminated Ge(111) Surfaces (open access)

Roles of Oxygen and Water Vapor in the Oxidation of Halogen Terminated Ge(111) Surfaces

The initial stage of the oxidation of Cl and Br terminated Ge(111) surfaces is studied using photoelectron spectroscopy. The authors perform controlled experiments to differentiate the effects of different factors in oxidation, and find that water vapor and oxygen play different roles. Water vapor effectively replaces the halogen termination layers with the hydroxyl group, but does not oxidize the surfaces further. In contrast, little oxidation is observed for Cl and Br terminated surfaces with dry oxygen alone. However, with the help of water vapor, oxygen oxidizes the surface by breaking the Ge-Ge back bonds instead of changing the termination layer.
Date: December 18, 2006
Creator: Sun, Shiyu; /Stanford U., Phys. Dept.; Sun, Yun; Liu, Zhi; Lee, Dong-Ick; Pianette, Piero et al.
Object Type: Article
System: The UNT Digital Library
[Funeral Program for Remethia Doris Winters, December 18, 2006] (open access)

[Funeral Program for Remethia Doris Winters, December 18, 2006]

Funeral program for Remethia Doris Winters, born January 14, 1925 and died December 8, 2006. The funeral was held December 18, 2006 at Greater Corinth Baptist Church, officiated by Dr. David J. Winters. Funeral arrangements were made by the Lewis Funeral Home, and she was buried in the Meadowlawn Memorial Park in San Antonio, Texas.
Date: December 18, 2006
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Trade Remedies: “New Shipper” Reviews (open access)

Trade Remedies: “New Shipper” Reviews

None
Date: December 18, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Comprehensive Immigration Reform Act of 2006 (S. 2611): Potential Labor Market Effects of the Guest Worker Program (open access)

The Comprehensive Immigration Reform Act of 2006 (S. 2611): Potential Labor Market Effects of the Guest Worker Program

None
Date: December 18, 2006
Creator: Mayer, Gerald
Object Type: Report
System: The UNT Digital Library
Civilian Patrols Along the Border: Legal and Policy Issues (open access)

Civilian Patrols Along the Border: Legal and Policy Issues

This report provides a history of civilian border patrol groups, with a focus on those groups operating along the southwest border, including most particularly, the "Minuteman Project". It also addresses some of the legal and policy issues that have surfaced from civilian activities at the border. The report concludes with an overview of legislative proposals introduced in the 109th Congress that addressed the issue of civilian border patrol groups.
Date: December 18, 2006
Creator: Vina, Stephen R. & Nnez-Neto, Blas
Object Type: Report
System: The UNT Digital Library