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Acquisition Workforce: Agencies Need to Better Define and Track the Training of Their Employees (open access)

Acquisition Workforce: Agencies Need to Better Define and Track the Training of Their Employees

A letter report issued by the General Accounting Office with an abstract that begins "GAO's continuing reviews of the acquisition workforce, focusing on the Department of Defense (DOD); the Departments of the Army, Navy, and Air Force; the Departments of Veterans Affairs, Energy, and Health and Human Services; the General Services Administration; and the National Aeronautics and Space Administration, indicate that some of the government's largest procurement operations are not run efficiently. GAO found that requirements are not clearly defined, prices and alternatives are not fully considered, or contracts are not adequately overseen. The ongoing technological revolution requires a workforce with new knowledge, skills, and abilities, and the nature of acquisition is changing from routine simple buys toward more complex acquisitions and new business practices. DOD has adopted multidisciplinary and multifunctional definitions of their acquisition workforce, but the civilian agencies have not. DOD and the civilian agencies reviewed have developed specific training requirements for their acquisition workforce and mechanisms to track the training of acquisition personnel. All of the agencies reviewed said they had sufficient funding to provide current required core training for their acquisition workforce, but some expressed concerns about funding training for future requirements and career development, particularly …
Date: July 29, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Overview of the SuperNova/Acceleration probe (SNAP) (open access)

Overview of the SuperNova/Acceleration probe (SNAP)

The SuperNova/Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter. The experiment is motivated by the startling discovery that the expansion of the Universe is accelerating. A 0.7 square-degree imager comprised of 36 large format fully-depleted n-type CCD's sharing a focal plane with 36 HgCdTe detectors forms the heart of SNAP, allowing discovery and lightcurve measurements simultaneously for many supernovae. The imager and a high-efficiency low-resolution integral field spectrograph are coupled to a 2-m three mirror anastigmat wide-field telescope, which will be placed in a high-earth orbit. The SNAP mission can obtain high-signal-to-noise calibrated light-curves and spectra for over 2000 Type Ia supernovae at redshifts between z = 0.1 and 1.7. The resulting data set can not only determine the amount of dark energy with high precision, but test the nature of the dark energy by examining its equation of state. In particular, dark energy due to a cosmological constant can be differentiated from alternatives such as ''quintessence'', by measuring the dark energy's equation of state to an accuracy of {+-} 0.05, and by studying its time dependence.
Date: July 29, 2002
Creator: galdering@lbl.gov
Object Type: Article
System: The UNT Digital Library
SNAP Telescope (open access)

SNAP Telescope

The SuperNova/Acceleration Probe (SNAP) mission will require a two-meter class telescope delivering diffraction limited images spanning a one degree field in the visible and near infrared wavelength regime. This requirement, equivalent to nearly one billion pixel resolution, places stringent demands on its optical system in terms of field flatness, image quality, and freedom from chromatic aberration. We discuss the advantages of annular-field three-mirror anastigmat (TMA) telescopes for applications such as SNAP, and describe the features of the specific optical configuration that we have baselined for the SNAP mission. We discuss the mechanical design and choice of materials for the telescope. Then we present detailed ray traces and diffraction calculations for our baseline optical design. We briefly discuss stray light and tolerance issues, and present a preliminary wavefront error budget for the SNAP Telescope. We conclude by describing some of tasks to be carried out during the upcoming SNAP research and development phase.
Date: July 29, 2002
Creator: Lampton, Michael L.; Akerlof, C. W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E. et al.
Object Type: Article
System: The UNT Digital Library
A study of layered lithium manganese oxide cathode materials (open access)

A study of layered lithium manganese oxide cathode materials

None
Date: July 29, 2002
Creator: Eriksson, Tom A. & Doeff, Marca M.
Object Type: Article
System: The UNT Digital Library
Microscopic probabilistic model for the simulation of secondary electron emission (open access)

Microscopic probabilistic model for the simulation of secondary electron emission

We provide a detailed description of a model and its computational algorithm for the secondary electron emission process. The model is based on a broad phenomenological fit to data for the secondary emission yield (SEY) and the emitted-energy spectrum. We provide two sets of values for the parameters by fitting our model to two particular data sets, one for copper and the other one for stainless steel.
Date: July 29, 2002
Creator: Furman, M. A. & Pivi, M. T. F.
Object Type: Article
System: The UNT Digital Library
Overview of the nearby supernova factory (open access)

Overview of the nearby supernova factory

The Nearby Supernova Factory (SNfactory) is an international experiment designed to lay the foundation for the next generation of cosmology experiments (such as CFHTLS, wP, SNAP and LSST) which will measure the expansion history of the Universe using Type Ia supernovae. The SNfactory will discover and obtain frequent lightcurve spectrophotometry covering 3200-10000 {angstrom} for roughly 300 Type Ia supernovae at the low-redshift end of the smooth Hubble flow. The quantity, quality, breadth of galactic environments, and homogeneous nature of the SNfactory dataset will make it the premier source of calibration for the Type Ia supernova width-brightness relation and the intrinsic supernova colors used for K-correction and correction for extinction by host-galaxy dust. This dataset will also allow an extensive investigation of additional parameters which possibly influence the quality of Type Ia supernovae as cosmological probes. The SNfactory search capabilities and follow-up instrumentation include wide-field CCD imagers on two 1.2-m telescopes (via collaboration with the Near Earth Asteroid Tracking team at JPL and the QUEST team at Yale), and a two-channel integral-field-unit optical spectrograph/imager being fabricated for the University of Hawaii 2.2-m telescope. In addition to ground-based follow-up, UV spectra for a subsample of these supernovae will be obtained with HST. …
Date: July 29, 2002
Creator: Aldering, Greg; Adam, Gilles; Antilogus, Pierre; Astier, Pierre; Bacon, Roland; Bongard, S. et al.
Object Type: Article
System: The UNT Digital Library
CO{sub 2}-H{sub 2}O mixtures in the geologic sequestration of CO{sub 2}. I. Assessment and calculation of mutual solubilities from 12 to 100 degrees C and up to 600 bar (open access)

CO{sub 2}-H{sub 2}O mixtures in the geologic sequestration of CO{sub 2}. I. Assessment and calculation of mutual solubilities from 12 to 100 degrees C and up to 600 bar

None
Date: July 29, 2002
Creator: Spycher, Nicolas; Pruess, Karsten & Ennis-King, Jonathan
Object Type: Article
System: The UNT Digital Library
High resolution XPS study of oxide layers grown on Ge substrates (open access)

High resolution XPS study of oxide layers grown on Ge substrates

High resolution X-ray Photoelectron Spectroscopy (XPS) was used to analyze thin layers of germanium oxide grown on germanium substrates under various conditions. The results reveal the presence of high density of electron states located at the oxide/germanium interface that lead to the energy band bending. The surface of native oxide layers and that of thin oxide layer grown under dry oxygen correspond to GeO2 composition. Under Ar etching, lower oxidation states were revealed. Short in-situ heat treatment at T=400 degrees C under ultra high vacuum leads to the removal of the oxide layer. In addition, the analysis of the layer grown at T=380 degrees C under dry oxygen suggest that carbides form at the oxide/substrate interface.
Date: July 29, 2002
Creator: Tabet, N.; Faiz, M.; Hamdan, N.M. & Hussain, Z.
Object Type: Article
System: The UNT Digital Library
Ferroelectric Cathodes in Transverse Magnetic Fields (open access)

Ferroelectric Cathodes in Transverse Magnetic Fields

Experimental investigations of a planar ferroelectric cathode in a transverse magnetic field up to 3 kGs are presented. It is shown that the transverse magnetic field affects differently the operation of ferroelectric plasma cathodes in ''bright'' and ''dark'' modes in vacuum. In the ''bright'' mode, when the surface plasma is formed, the application of the transverse magnetic field leads to an increase of the surface plasma density. In the ''dark'' mode, the magnetic field inhibits the development of electron avalanches along the surface, as it does similarly in other kinds of surface discharges in the pre-breakdown mode.
Date: July 29, 2002
Creator: Dunaevsky, Alexander; Raitses, Yevgeny & Fisch, Nathaniel J.
Object Type: Report
System: The UNT Digital Library
The influence of pre-irradiation heat treatments on thermal non-equilibrium and radiation-induced segregation behavior in model austenitic stainless steel alloys. (open access)

The influence of pre-irradiation heat treatments on thermal non-equilibrium and radiation-induced segregation behavior in model austenitic stainless steel alloys.

The effect of pre-irradiation heat treatments on thermal non-equilibrium grain boundary segregation (TNES) and subsequent radiation-induced grain boundary segregation (RIS) is studied in a series of model austenitic stainless steels. The alloys used for this study are based on AISI 316 stainless steel and have the following nominal compositions: Fe-16Cr-13Ni-1.25Mn (base 316), Fe-16Cr-13Ni-1.25Mn-2.0Mo (316 + Mo) and Fe-16Cr-13Ni-1.25Mn-2.0Mo-0.07P (316 + Mo + P). Samples were heat treated at temperatures ranging from 1100 to 1300 C and cooled at 4 different rates (salt brine quench, water quench, air cool and furnace cool) to evaluate the effect of annealing temperature and quench rate on TNES. The alloys were than processed with the treatment (temperature and cooling rate) that resulted in the maximum Cr enrichment. Alloys with and without the heat treatment to enrich the grain boundaries with Cr were characterized following irradiation to 1 dpa at 400 C with high-energy protons in order to understand the influence of alloying additions and pre-irradiation grain boundary chemistry on irradiation-induced elemental enrichment and depletion profiles. Various mechanistic models will be examined to explain the observed behavior.
Date: July 29, 2002
Creator: Cole, J. I.; Allen, T. R.; Was, G. S.; Dropek, R. B. & Kenik, E. A.
Object Type: Article
System: The UNT Digital Library
Environmental Aspects, Objectives and Targets Identification Process (open access)

Environmental Aspects, Objectives and Targets Identification Process

The purpose of this report is to document the environmental aspects and associated environmental impacts of the Bechtel SAIC Company (BSC) scope of work, evaluate the significance of those environmental aspects based on established criteria, and establish environmental objectives and targets for specific environmental aspects. This report is intended to be used by environmental staff in the evaluation of BSC work packages during the annual risk-based planning process. This report shall be fully reviewed and revised annually during the annual work planning process to reflect changes in BSC operations, facilities, and scope of work. Planned BSC work will be evaluated to determine if the work is covered by a previously defined activity, product or service (see Table 2); if work activities require redefinition or addition of a new activity; and if the significant evaluation for each environment aspect is still valid based on scope of planned work. New workscope initiated during the fiscal year through the Baseline Change Proposal process (i.e., not as part of the annual work plan) also will be reviewed for new environmental aspects and determination of whether the new workscope would change the significance rating of any environmental aspect. If a new environmental aspect is identified …
Date: July 29, 2002
Creator: Green, R.
Object Type: Report
System: The UNT Digital Library
SNAP Near Infrared Detectors (open access)

SNAP Near Infrared Detectors

The SuperNova/Acceleration Probe (SNAP) will measure precisely the cosmological expansion history over both the acceleration and deceleration epochs and thereby constrain the nature of the dark energy that dominates our universe today. The SNAP focal plane contains equal areas of optical CCDs and NIR sensors and an integral field spectrograph. Having over 150 million pixels and a field-of-view of 0.34 square degrees, the SNAP NIR system will be the largest yet constructed. With sensitivity in the range 0.9-1.7 {micro}m, it will detect Type Ia supernovae between z = 1 and 1.7 and will provide follow-up precision photometry for all supernovae. HgCdTe technology, with a cut-off tuned to 1.7 {micro}m, will permit passive cooling at 140 K while maintaining noise below zodiacal levels. By dithering to remove the effects of intrapixel variations and by careful attention to other instrumental effects, we expect to control relative photometric accuracy below a few hundredths of a magnitude. Because SNAP continuously revisits the same fields we will be able to achieve outstanding statistical precision on the photometry of reference stars in these fields, allowing precise monitoring of our detectors. The capabilities of the NIR system for broadening the science reach of SNAP are discussed.
Date: July 29, 2002
Creator: Tarle, G.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E. et al.
Object Type: Article
System: The UNT Digital Library
Trapped Electron Precession Shear Induced Fluctuation Decorrelation (open access)

Trapped Electron Precession Shear Induced Fluctuation Decorrelation

We consider the effects of trapped electron precession shear on the microturbulence. In a similar way the strong E x B shear reduces the radial correlation length of ambient fluctuations, the radial variation of the trapped electron precession frequency can reduce the radial correlation length of fluctuations associated with trapped electrons. In reversed shear plasmas, with the explicit dependence of the trapped electron precession shearing rate on B(subscript)theta, the sharp radial gradient of T(subscript)e due to local electron heating inside qmin can make the precession shearing mechanism more effective, and reduce the electron thermal transport constructing a positive feedback loop for the T(subscript)e barrier formation.
Date: July 29, 2002
Creator: Hahm, T.S.; Diamond, P.H. & Kim, E.-J.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 245, Ed. 1 Monday, July 29, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 245, Ed. 1 Monday, July 29, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 29, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Combining Distributed and Shared Memory Models: Approach and Evolution of the Global Arrays Toolkit (open access)

Combining Distributed and Shared Memory Models: Approach and Evolution of the Global Arrays Toolkit

Both shared memory and distributed memory models have advantages and shortcomings. Shared memory model is much easier to use but it ignores data locality/placement. Given the hierarchical nature of the memory subsystems in the modern computers this characteristic might have a negative impact on performance and scalability. Various techniques, such as code restructuring to increase data reuse and introducing blocking in data accesses, can address the problem and yield performance competitive with message passing[Singh], however at the cost of compromising the ease of use feature. Distributed memory models such as message passing or one-sided communication offer performance and scalability but they compromise the ease-of-use. In this context, the message-passing model is sometimes referred to as?assembly programming for the scientific computing?. The Global Arrays toolkit[GA1, GA2] attempts to offer the best features of both models. It implements a shared-memory programming model in which data locality is managed explicitly by the programmer. This management is achieved by explicit calls to functions that transfer data between a global address space (a distributed array) and local storage. In this respect, the GA model has similarities to the distributed shared-memory models that provide an explicit acquire/release protocol. However, the GA model acknowledges that remote data …
Date: July 29, 2002
Creator: Nieplocha, Jarek; Harrison, Robert J.; Kumar, Mukul; Palmer, Bruce J.; Tipparaju, Vinod & Trease, Harold E.
Object Type: Article
System: The UNT Digital Library
Eyeglass: A Very Large Aperture Diffractive Space Telescope (open access)

Eyeglass: A Very Large Aperture Diffractive Space Telescope

Eyeglass is a very large aperture (25-100 meter) space telescope consisting of two distinct spacecraft, separated in space by several kilometers. A diffractive lens provides the telescope's large aperture, and a separate, much smaller, space telescope serves as its mobile eyepiece. Use of a transmissive diffractive lens solves two basic problems associated with very large aperture space telescopes; it is inherently fieldable (lightweight and flat, hence packagable and deployable) and virtually eliminates the traditional, very tight, surface shape tolerances faced by reflecting apertures. The potential drawback to use of a diffractive primary (very narrow spectral bandwidth) is eliminated by corrective optics in the telescope's eyepiece. The Eyeglass can provide diffraction-limited imaging with either single-band, multiband, or continuous spectral coverage. Broadband diffractive telescopes have been built at LLNL and have demonstrated diffraction-limited performance over a 40% spectral bandwidth (0.48-0.72 {micro}m). As one approach to package a large aperture for launch, a foldable lens has been built and demonstrated. A 75 cm aperture diffractive lens was constructed from 6 panels of 1 m thick silica; it achieved diffraction-limited performance both before and after folding. This multiple panel, folding lens, approach is currently being scaled-up at LLNL. We are building a 5 meter …
Date: July 29, 2002
Creator: Hyde, R; Dixit, S; Weisberg, A & Rushford, M
Object Type: Article
System: The UNT Digital Library
Test of the ITER TF Insert and Central Solenoid Model Coil (open access)

Test of the ITER TF Insert and Central Solenoid Model Coil

The Central Solenoid Model Coil (CSMC) was designed and built by ITER collaboration between the European Union, Japan, Russian Federation and the United States in 1993-2001. Three heavily instrumented insert coils have been also built for testing in the background field of the CSMC to cover a wide operational space. The TF Insert was designed and built by the Russian Federation to simulate the conductor performance under the ITER TF coil conditions. The TF Insert Coil was tested in the CSMC Test Facility at the Japan Atomic Energy Research Institute, Naka, Japan in September-October 2001. Some measurements were performed also on the CSMC to study effects of electromagnetic and cooldown cycles. The TF Insert coil was charged successfully, without training, in the background field of the CSMC to the design current of 46 kA at 13 T peak field. The TF Insert met or exceeded all design objectives, however some interesting results require thorough analyses. This paper presents the overview of main results of the testing--magnet critical parameters, ac losses, joint performance, effect of cycles on performance, quench and thermo-hydraulic characteristics and some results of the post-test analysis.
Date: July 29, 2002
Creator: Martovetsky, N.; Takayasu, M.; Minervini, J.; Isono, T.; Sugimoto, M.; Kato, T. et al.
Object Type: Article
System: The UNT Digital Library
Test of the Nb/A1 Insert and ITER Central Solenoid Model Coil (open access)

Test of the Nb/A1 Insert and ITER Central Solenoid Model Coil

The Central Solenoid Model Coil (CSMC) was designed and built by an ITER collaboration in 1993-2001. Three heavily instrumented Inserts have been also built for testing in the background field of the CSMC. The Nb3AI Insert was designed and built by Japan to explore the feasibility of an alternative to Nb3Sn superconductor for fusion magnets. The Nb3AI Insert coil was tested in the CSMC Test Facility at the Japan Atomic Energy Research Institute, Naka, Japan in March-May 2002. It was the third Insert tested in this facility under this program. The Nb3AI Insert coil was charged successfully without training in the background field of the CSMC to the design current of 46 kA at 13 T peak field and later was successfully charged up to 60 kA in 12.5 T field. This paper presents the test results overview.
Date: July 29, 2002
Creator: Martovetsky, N.; Okuno, K.; Koizumi, N.; Sugimoto, M.; Isono, T.; Hamada, K. et al.
Object Type: Article
System: The UNT Digital Library
SNAP Focal Plane (open access)

SNAP Focal Plane

The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square-degree field sensitive in the visible and near-infrared wavelength regime. We describe the requirements for the instrument suite and the evolution of the focal plane design to the present concept in which all the instrumentation--visible and near-infrared imagers, spectrograph, and star guiders--share one common focal plane.
Date: July 29, 2002
Creator: Lampton, Michael L.; Kim, A.; Akerlof, C. W.; Aldering, G.; Amanullah, R.; Astier, P. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 104, No. 115, Ed. 1 Monday, July 29, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 115, Ed. 1 Monday, July 29, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 29, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 111, No. 60, Ed. 1 Monday, July 29, 2002 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 111, No. 60, Ed. 1 Monday, July 29, 2002

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: July 29, 2002
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Recent developments at the cathode processor for spent fuel treatment. (open access)

Recent developments at the cathode processor for spent fuel treatment.

As part of the spent fuel treatment program at Argonne National Laboratory, a vacuum distillation process is being employed for the recovery of uranium following an electrorefining process. Distillation of a molten salt electrolyte, primarily consisting of a eutectic mixture of lithium and potassium chlorides with minor amounts of fission product chlorides, from uranium is achieved by a batch operation called cathode processing. Described in this paper are recent developments, both equipment and process-related, at the cathode processor during the treatment of blanket-type spent fuel. For the equipment developments, the installation of a new induction heating coil has produced significant improvements in equipment performance. The process developments include the elimination of a process step and the study of plutonium in the uranium product.
Date: July 29, 2002
Creator: Westphal, B. R.; Vaden, D.; Hua, T. Q.; Willit, J. L. & Laug, D. V.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 29, 2002 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 29, 2002

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 29, 2002
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The National Institute of Standards and Technology: An Overview (open access)

The National Institute of Standards and Technology: An Overview

None
Date: July 29, 2002
Creator: Schacht, Wendy H.
Object Type: Report
System: The UNT Digital Library