960 Matching Results

Search Results

Results: 1 - 24 next
open access

Simulation of the Future LSST Data Pipelines

Description: In this paper we describe our approach to build a pipeline simulator for the future Large-scale Synoptic Survey Telescope (LSST). The simulated pipeline will be used to research and evaluate software architectures that are efficient and flexible. It will also be used to define the real-time software and hardware requirements needed to support the anticipated LSST data rates. The LSST data pipeline requirements are still being defined, however, previous surveys can provide a good source for data requirements. Our approach is to use the SuperMacho data pipeline as a prototyping tool to identify a framework for building Modular Data-Centric Pipeline (MDCP) architectures. The prototyping is done in a hierarchical fashion to help capture and define the general data attributes (schema) first. We then model other necessary components based on science and performance requirements. We use identified schemas or data attributes as a way to define a data model for LSST.
Date: July 26, 2004
Creator: Abdulla, Ghaleb M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of charged particle multiplicities in gluon and quark jets in proton anti-proton collisions at s**(1/2) = 1.8-TeV

Description: The authors report the first model independent measurement of charged particle multiplicities in quark and gluon jets, N{sub q} and N{sub g}, produced at the Tevatron in p{bar p} collisions with center-of-mass energy 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies 41 and 53 GeV by counting charged particle tracks in cones with opening angle of {theta}{sub c} = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = E{sub jet}{theta}{sub c} varies in the range from 12 GeV to 25 GeV. At Q = 19 GeV, the ratio of multiplicities r = N{sub g}/N{sub q} is found to be 1.64 {+-} 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with re-summed perturbative QCD calculations.
Date: July 1, 2004
Creator: Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurements of Transverse Energy Distributions in Au+Au Collisions at {radical}s{sub NN} = 200 GeV

Description: Transverse energy (E{sub T}) distributions have been measured for Au+Au collisions at {radical}s{sub NN} = 200 GeV by the STAR collaboration at RHIC. E{sub T} is constructed from its hadronic and electromagnetic components, which have been measured separately. E{sub T} production for the most central collisions is well described by several theoretical models whose common feature is large energy density achieved early in the fireball evolution. The magnitude and centrality dependence of E{sub T} per charged particle agrees well with measurements at lower collision energy, indicating that the growth in E{sub T} for larger collision energy results from the growth in particle production. The electromagnetic fraction of the total E{sub T} is consistent with a final state dominated by mesons and independent of centrality.
Date: July 2, 2004
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Level densities and gamma-ray strength functions in 170,171,172-Yb

Description: Level densities and radiative strength functions in {sup 171}Yb and {sup 170}Yb nuclei have been measured using the {sup 171}Yb({sup 3}He{sup 3}He{gamma}){sup 171}Yb and {sup 171}Yb({sup 3}He,{alpha}{gamma}){sup 170}Yb reactions. New data on {sup 171}Yb are compared to a previous measurement for {sup 171}Yb from the {sup 172}Yb({sup 3}He,{alpha}{gamma}){sup 171}Yb reaction. Systematics of level densities and radiative strength functions in {sup 170,171,172}Yb are established. The entropy excess in {sup 171}Yb relative to the even-even nuclei {sup 170,172}Yb due to the unpaired neutron quasiparticle is found to be approximately 2k{sub B}. Results for the radiative strength function from the two reactions lead to consistent parameters characterizing the ''pygmy'' resonances. Pygmy resonances in the {sup 170,172}Yb populated by the ({sup 3}He,{alpha}) reaction appear to be split into two components for both of which a complete set of resonance parameters are obtained.
Date: July 28, 2004
Creator: Agvaanluvsan, U.; Schiller, A.; Becker, J.; Bernstein, L.; Garrett, P.; Guttormsen, M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Monitoring the Energy-Use Effects of Cool Roofs on California Commercial Buildings

Description: Solar-reflective roofs stay cooler in the sun than solar-absorptive roofs. Such ''cool'' roofs achieve lower surface temperatures that reduce heat conduction into the building and the building's cooling load. The California Energy Commission has funded research in which Lawrence Berkeley National Laboratory (LBNL) has measured the electricity use and peak demand in commercial buildings to document savings from implementing the Commission's Cool Roofs program. The study seeks to determine the savings achieved by cool roofs by monitoring the energy use of a carefully selected assortment of buildings participating in the Cool Roofs program. Measurements were needed because the peak savings resulting from the application of cool roofs on different types of buildings in the diverse California climate zones have not been well characterized to date. Only a few occupancy categories (e.g., office and retail buildings) have been monitored before this, and those were done under a limited number of climatic conditions. To help rectify this situation, LBNL was tasked to select the buildings to be monitored, measure roof performance before and after replacing a hot roof by a cool roof, and document both energy and peak demand savings resulting from installation of cool roofs. We monitored the effects of cool roofs on energy use and environmental parameters in six California buildings at three different sites: a retail store in Sacramento; an elementary school in San Marcos (near San Diego); and a 4-building cold storage facility in Reedley (near Fresno). The latter included a cold storage building, a conditioning and fruit-palletizing area, a conditioned packing area, and two unconditioned packing areas (counted as one building).
Date: July 1, 2004
Creator: Akbari, Hashem; Levinson, Ronnen; Konopaki, Steve & Rainer, Leo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Oral History Interview with Harlan W. Crouse, July 2, 2004

Description: Interview with Army veteran Harlan W. Crouse. The interview includes Crouse's personal experiences about combat in the Philippines during World War II, the Japanese surrender in Yokohama Harbor, and being present during the post-war U.S. occupation of Japan.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: July 2, 2004
Creator: Alexander, William J. & Crouse, Harlan W.
Item Type: Refine your search to only Book
Partner: UNT Oral History Program
open access

Sub-Angstrom metrology of resolution in aberration-corrected transmission electron microscopes using the A-OK standard test specimens

Description: Using specimens with diamond cubic and zincblende structures, oriented to provide pairs of atoms in ''dumbbell'' configurations, we have identified specimens with well-characterized atom separations over a 3:1 range of spacings straddling the canonical 1 Angstrom value. Spacings ranging from 1.6 Angstrom to 0.5 Angstrom are available from an ''A-OK'' set of test specimens carefully selected for their stability and well-characterized lattice parameters.
Date: July 1, 2004
Creator: Allard, Lawrence F. & O'Keefe, Michael A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

House Committee on Standards of Official Conduct: A Brief History of Its Evolution and Jurisdiction

Description: This report provides a history of the creation and evolution of the House Committee on Standards of Official Conduct. Also known as the House Ethics Committee and the Committee on Standards, it was first established as a select committee in 1966. It became a standing committee in 1967. Since that time, it has undergone two major reorganizations, first in 1989, and again in 1997.
Date: July 14, 2004
Creator: Amer, Mildred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Membership of the 108th Congress: A Profile

Description: This report presents a profile of the membership of the 108th Congress. Included is information on numbers of Members, party affiliation, average age and length of service, occupations, religious affiliation, military service, female and minority Members, and foreign-born Members.
Date: July 28, 2004
Creator: Amer, Mildred L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Synergia: an accelerator modeling tool with 3-D space charge

Description: High precision modeling of space-charge effects, together with accurate treatment of single-particle dynamics, is essential for designing future accelerators as well as optimizing the performance of existing machines. We describe Synergia, a high-fidelity parallel beam dynamics simulation package with fully three dimensional space-charge capabilities and a higher order optics implementation. We describe the computational techniques, the advanced human interface, and the parallel performance obtained using large numbers of macroparticles. We also perform code benchmarks comparing to semi-analytic results and other codes. Finally, we present initial results on particle tune spread, beam halo creation, and emittance growth in the Fermilab booster accelerator.
Date: July 1, 2004
Creator: Amundson, James F.; Spentzouris, P.; Qiang, J. & Ryne, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ES-3100: A New Generation Shipping Container for Bulk Highly Enriched Uranium and Other Fissile Materials

Description: The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA) is shipping bulk quantities of surplus fissile materials, primarily highly enriched uranium (HEU), over the next 15 to 20 years for disposition purposes. The U.S. Department of Transportation (DOT) specification 6M container is the package of choice for most of these shipments. However, the 6M does not conform to the Type B packaging requirements in the ''Code of Federal Regulations'' (10CFR71) and, for that reason, is being phased out for use in the secure transportation system of DOE. BWXT Y-12 is currently developing a package to replace the DOT 6M container for HEU disposition shipping campaigns. The new package is based on state-of-the-art, proven, and patented insulation technologies that have been successfully applied in the design of other packages. The new package, designated the ES-3100, will have a 50% greater capacity for HEU than the 6M and will be easier to use. Engineering analysis on the new package includes detailed dynamic impact finite element analysis (FEA). This analysis gives the ES-3100 a high probability of complying with regulatory requirements.
Date: July 1, 2004
Creator: Arbital, J.G.; Byington, G.A. & Tousley, D.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Renewable Energy Water Pumping Systems Handbook; Period of Performance: April 1--September 1, 2001

Description: Water is one of the most basic necessities of rural development. This book provides valuable information on how renewable energy technologies can be used for irrigation, livestock watering, and domestic water supplies. This report emphasizes wind and solar energy resources, and hybrid water pumping systems.
Date: July 1, 2004
Creator: Argaw, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

NOVEL COMPOSITE HYDROGEN-PERMEABLE MEMBRANES FOR NON-THERMAL PLASMA REACTORS FOR THE DECOMPOSITION OF HYDROGEN SULFIDE

Description: The goal of this experimental project is to design and fabricate a reactor and membrane test cell to dissociate hydrogen sulfide (H{sub 2}S) in a non-thermal plasma and recover hydrogen (H{sub 2}) through a superpermeable multi-layer membrane. Superpermeability of hydrogen atoms (H) has been reported by some researchers using membranes made of Group V transition metals (niobium, tantalum, vanadium, and their alloys), although it has yet to be confirmed in this study. Experiments involving methane conversion reactions were conducted with a preliminary pulsed corona discharge reactor design in order to test and improve the reactor and membrane designs using a non-toxic reactant. This report details the direct methane conversion experiments to produce hydrogen, acetylene, and higher hydrocarbons utilizing a co-axial cylinder (CAC) corona discharge reactor, pulsed with a thyratron switch. The reactor was designed to accommodate relatively high flow rates (655 x 10{sup -6} m{sup 3}/s) representing a pilot scale easily converted to commercial scale. Parameters expected to influence methane conversion including pulse frequency, charge voltage, capacitance, residence time, and electrode material were investigated. Conversion, selectivity and energy consumption were measured or estimated. C{sub 2} and C{sub 3} hydrocarbon products were analyzed with a residual gas analyzer (RGA). In order to obtain quantitative results, the complex sample spectra were de-convoluted via a linear least squares method. Methane conversion as high as 51% was achieved. The products are typically 50%-60% acetylene, 20% propane, 10% ethane and ethylene, and 5% propylene. First Law thermodynamic energy efficiencies for the system (electrical and reactor) were estimated to range from 38% to 6%, with the highest efficiencies occurring at short residence time and low power input (low specific energy) where conversion is the lowest (less than 5%). The highest methane conversion of 51% occurred at a residence time of 18.8 s with a flow rate …
Date: July 1, 2004
Creator: Argyle, Morris D.; Ackerman, John F.; Muknahallipatna, Suresh; Hamann, Jerry C.; Legowski, Stanislaw; Zhang, Ji-Jun et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Functional One-Dimensional Lipid Bilayers on Carbon Nanotube Templates

Description: We present one-dimensional (1-D) lipid bilayer structures that integrate carbon nanotubes with a key biological environment-phospholipid membrane. Our structures consist of lipid bilayers wrapped around carbon nanotubes modified with a hydrophilic polymer cushion layer. Despite high bilayer curvature, the lipid membrane maintains its fluidity and can sustain repeated damage-recovery cycles. We also present the first evidence of spontaneous insertion of pore-forming proteins into 1-D lipid bilayers. These structures could lead to the development of new classes of biosensors and bioelectronic devices.
Date: July 23, 2004
Creator: Artyukhin, Alexander; Shestakov, Alexei; Harper, Jennifer; Bakajin, Olgica; Stroeve, Pieter & Noy, Aleksandr
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Commercial Demonstration of Wood Recovery, Recycling, and Value Adding Technologies

Description: This commercial demonstration project demonstrated the technical feasibility of converting low-value, underutilized and waste stream solid wood fiber material into higher valued products. With a growing need to increase product/production yield and reduce waste in most sawmills, few recovery operations and practically no data existed to support the viability of recovery operations. Prior to our efforts, most all in the forest products industry believed that recovery was difficult, extremely labor intensive, not cost effective, and that recovered products had low value and were difficult to sell. This project provided an opportunity for many within the industry to see through demonstration that converting waste stream material into higher valued products does in fact offer a solution. Our work, supported by the U.S. Department of Energy, throughout the project aimed to demonstrate a reasonable approach to reducing the millions of recoverable solid wood fiber tons that are annually treated as and converted into low value chips, mulch and fuel. Consequently sawmills continue to suffer from reduced availability of forest resources, higher raw material costs, growing waste disposal problems, increased global competition, and more pressure to operate in an Environmentally Friendly manner. It is our belief (based upon the experience of this project) that the successful mainstreaming of the recovery concept would assist in alleviating this burden as well as provide for a realistically achievable economic benefit to those who would seriously pursue the concept and tap into the rapidly growing ''GREEN'' building marketplace. Ultimately, with participation and aggressive pursuit of the recovery concept, the public would benefit in that: (1) Landfill/disposal waste volume could be reduced adding greater life to existing municipal landfill sites thereby minimizing the need to prematurely license and open added facilities. Also, there would be a cost avoidance benefit associated to what would have been the added municipal …
Date: July 15, 2004
Creator: Auburn Machinery, Inc.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

History of the Offshore Oil and Gas Industry in Southern Louisiana, Interim Report: Volume 1. Papers on the Evolving Offshore Industry

Description: An historical evaluation and documentation of the offshore oil and gas industry and its impact on the economy of Southern Louisiana from its inception in the early decades of the twentieth century.
Date: July 2004
Creator: Austin, Diane; Carriker, Bob; McGuire, Tom; Pratt, Joseph; Priest, Tyler & Pulsipher, Allan G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen