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

Description: 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.… more
Date: July 29, 2002
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Overview of the SuperNova/Acceleration probe (SNAP)

Description: 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 m… more
Date: July 29, 2002
Creator: galdering@lbl.gov
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SNAP Telescope

Description: 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 applic… more
Date: July 29, 2002
Creator: Lampton, Michael L.; Akerlof, C. W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Microscopic probabilistic model for the simulation of secondary electron emission

Description: 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.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Overview of the nearby supernova factory

Description: 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 … more
Date: July 29, 2002
Creator: Aldering, Greg; Adam, Gilles; Antilogus, Pierre; Astier, Pierre; Bacon, Roland; Bongard, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High resolution XPS study of oxide layers grown on Ge substrates

Description: 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 he… more
Date: July 29, 2002
Creator: Tabet, N.; Faiz, M.; Hamdan, N.M. & Hussain, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Ferroelectric Cathodes in Transverse Magnetic Fields

Description: 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 develop… more
Date: July 29, 2002
Creator: Dunaevsky, Alexander; Raitses, Yevgeny & Fisch, Nathaniel J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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 t… more
Date: July 29, 2002
Creator: Cole, J. I.; Allen, T. R.; Was, G. S.; Dropek, R. B. & Kenik, E. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Environmental Aspects, Objectives and Targets Identification Process

Description: 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… more
Date: July 29, 2002
Creator: Green, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SNAP Near Infrared Detectors

Description: 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 t… more
Date: July 29, 2002
Creator: Tarle, G.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Trapped Electron Precession Shear Induced Fluctuation Decorrelation

Description: 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 … more
Date: July 29, 2002
Creator: Hahm, T.S.; Diamond, P.H. & Kim, E.-J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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 wit… more
Date: July 29, 2002
Creator: Nieplocha, Jarek; Harrison, Robert J.; Kumar, Mukul; Palmer, Bruce J.; Tipparaju, Vinod & Trease, Harold E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Eyeglass: A Very Large Aperture Diffractive Space Telescope

Description: 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 … more
Date: July 29, 2002
Creator: Hyde, R; Dixit, S; Weisberg, A & Rushford, M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Test of the ITER TF Insert and Central Solenoid Model Coil

Description: 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 Tes… more
Date: July 29, 2002
Creator: Martovetsky, N.; Takayasu, M.; Minervini, J.; Isono, T.; Sugimoto, M.; Kato, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Test of the Nb/A1 Insert and ITER Central Solenoid Model Coil

Description: 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 I… more
Date: July 29, 2002
Creator: Martovetsky, N.; Okuno, K.; Koizumi, N.; Sugimoto, M.; Isono, T.; Hamada, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SNAP Focal Plane

Description: 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.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent developments at the cathode processor for spent fuel treatment.

Description: 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 an… more
Date: July 29, 2002
Creator: Westphal, B. R.; Vaden, D.; Hua, T. Q.; Willit, J. L. & Laug, D. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High Resolution X-Ray Fluorescence Micro-Tomography on Single Sediment Particles

Description: This work focuses on the investigation of the distribution of contaminants in individual sediment particles from the New York/New Jersey Harbor. Knowledge of the spatial distribution of the contaminants within the particles is needed to enable (1) more sophisticated approaches to the understanding of the fate and transport of the contaminants in the environment and (2) more refined methods for cleaning the sediments. The size of the investigated particles ranges from 30-80 microns. Due to the l… more
Date: July 29, 2002
Creator: Vincze, L.; Vekemans, B.; Szaloki, I.; Janssens, K.; Van Grieken, R.; Feng, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An integral field spectrograph for SNAP supernova studies

Description: A well-adapted spectrograph concept has been developed for the SNAP (SuperNova/Acceleration Probe) experiment. The goal is to ensure proper identification of Type Ia supernovae and to standardize the magnitude of each candidate by determining explosion parameters. An instrument based on an integral field method with the powerful concept of imager slicing has been designed and is presented in this paper. The spectrograph concept is optimized to have very high efficiency and low spectral resoluti… more
Date: July 29, 2002
Creator: Ealet, Anne; Prieto, E.; Bonissent, A.; Malina, R.; Basa, S.; LeFevre, O. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Regulatory Framework for the Geologic Repository at Yucca Mountain Nevada, USA

Description: After years of geologic investigations, Yucca Mountain, Nevada has been recommended by the President of the United States and approved by the U.S. Congress for development as a geologic repository for disposal of high-level radioactive waste and spent nuclear fuel. This significant step forward in implementing national policy for the safe and environmentally sound isolation of radioactive waste was made possible, in part, by the finalization of the regulatory framework for the U.S. repository p… more
Date: July 29, 2002
Creator: Gil, A.V. & McKinnon, B.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Processing and Microstructure of Cr-Ta and Cr-Ta-Mo Composites Reinforced by the Cr2Ta Laves Phase

Description: The Cr-Ta alloy with an eutectic structure has a good combination of high strength and oxidation resistance at elevated temperatures up to 1200 C. It is an ideal candidate for ultrahigh-temperature applications. However, the material shows low ductility and fracture toughness at room temperature. A possible way to improve the ductility and fracture toughness is to obtain an aligned microstructure of eutectic Cr-based alloys, using a directional-solidification (DS) process, in which the feed mat… more
Date: July 29, 2002
Creator: Wang, DF
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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