495 Matching Results

Search Results

Results: 1 - 24 next
open access

A Measurement of the Top Quark Mass with the D0 Detector at s**(1/2) = 1.96-TeV using the Matrix Element Method

Description: Using a data set of 158 and 169 pb{sup -1} of D0 Run-II data in the electron and muon plus jets channel, respectively, the top quark mass has been measured using the Matrix Element Method. The method and its implementation are described. Its performance is studied in Monte Carlo using ensemble tests and the method is applied to the Moriond 2004 data set.
Date: April 1, 2004
Creator: Kroeninger, Kevin Alexander
Partner: UNT Libraries Government Documents Department
open access

3D Computations and Experiments

Description: This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE3D Development, involves general development activities in the ALE3D code with the focus o… more
Date: April 5, 2004
Creator: Couch, R; Faux, D; Goto, D & Nikkel, D
Partner: UNT Libraries Government Documents Department
open access

Precision Micron Hole Drilling using a Frequency Doubled, Diode Pumped Solid State Laser

Description: This work represents the second phase of a program to demonstrate precision laser drilling with minimal Heat Affected Zone. The technique uses a Diode Pumped Solid State Laser with two wavelengths and two modes of operation. The fundamental mode of the DPSSL at 1.06 microns is used to drill a hole with a diameter of a fraction of a millimeter diameter in a millimeter thick substrate quickly, but with low precision. This hole is then machined to precision dimensions using the second harmonic of … more
Date: April 21, 2004
Creator: Friedman, H W & Pierce, E L
Partner: UNT Libraries Government Documents Department
open access

Adaptive 4-8 Texture Hierarchies

Description: No Description Available.
Date: April 14, 2004
Creator: Hwa, L M; Duchaineau, M A & Joy, K I
Partner: UNT Libraries Government Documents Department
open access

Aerodynamic Design of Heavy Vehicles Reporting Period January 15, 2004 through April 15, 2004

Description: Listed are summaries of the activities and accomplishments during this second-quarter reporting period for each of the consortium participants. The following are some highlights for this reporting period: (1) Experiments and computations guide conceptual designs for reduction of drag due to tractor-trailer gap flow (splitter plate), trailer underbody (wedges), and base drag (base-flap add-ons). (2) Steady and unsteady RANS simulations for the GTS geometry are being finalized for development of … more
Date: April 13, 2004
Creator: Leonard, A.; Chatelain, P.; Heineck, J.; Browand, F.; Mehta, R.; Ortega, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Direct Carbon Fuel Cells: Assessment of their Potential as Solid Carbon Fuel Based Power Generation Systems

Description: Small-scale experimental work at Lawrence Livermore National Laboratory (LLNL) has confirmed that a direct carbon fuel cell (DCFC) containing a molten carbonate electrolyte completely reacts solid elemental carbon with atmospheric oxygen contained in ambient air at a temperature of 650-800 C. The efficiency of conversion of the chemical energy in the fuel to DC electricity is 75-80% and is a result of zero entropy change for this reaction and the fixed chemical potentials of C and CO{sub 2}. Th… more
Date: April 23, 2004
Creator: Wolk, R
Partner: UNT Libraries Government Documents Department
open access

Detection of nuclear threats in large cargo containers

Description: In 2003 scientists at the Lawrence Livermore National Laboratory, the Lawrence Berkeley National Laboratory, and the University of California at Berkeley undertook a collaborative effort. The goal of this collaboration is to develop a concept for an active neutron interrogation system that can detect small masses of contraband fissile material in intermodal cargo containers--roughly five kg of highly-enriched-uranium or one kg of plutonium--even when well shielded by thick cargo. It is essentia… more
Date: April 19, 2004
Creator: Gosnell, T B
Partner: UNT Libraries Government Documents Department
open access

Summary of Hanford Site Groundwater Monitoring for Fiscal Year 2003

Description: This document is a summary of the larger report, PNNL-14548. It describes the groundwater monitoring results for FY 2003 at the Hanford Site in southeast Washington State. The Hanford Site, a facility in the U.S. Department of Energy (DOE) nuclear weapons complex, encompasses {approx}1,517 square kilometers northwest of the city of Richland along the Columbia River in southeast Washington State. The federal government acquired the site in 1943, and until the 1980s it was dedicated primarily to … more
Date: April 12, 2004
Creator: Hartman, Mary J.; Morasch, Launa F. & Webber, William D.
Partner: UNT Libraries Government Documents Department
open access

A Geostatistical Analysis of Historical Field Data on Tritium, Technetium-99, Iodine-129, and Uranium

Description: The purpose of the study described in this report was to generate maps and statistics that quantify contamination in groundwater, based on historical groundwater concentration data for multiple points in time. The results generated from this study include several quantitative summaries of contaminant distributions (e.g., the location of the center of mass of contaminant plumes and the total mass of contaminants in the plume) and are collectively referred to as history matching data. A primary g… more
Date: April 26, 2004
Creator: Murray, Christopher J.; Chien, Yi-Ju & Thorne, Paul D.
Partner: UNT Libraries Government Documents Department
open access

Post-Closure Groundwater Monitoring Plan for the 1324-N Surface Impoundment and 1324-NA Percolation Pond

Description: The 1324-N Surface Impoundment and the 1324-NA Percolation Pond, located in the 100-N Area of the Hanford Site, are regulated under the Resource Consevation and Recovery Act (RCRA). Surface and underground features of the facilities have been removed and laboratory analyses showed that soil met the closure performance standards. These sites have been backfilled and revegetated.
Date: April 2, 2004
Creator: Hartman, Mary J.
Partner: UNT Libraries Government Documents Department
open access

How Accurately can we Calculate Thermal Systems?

Description: I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it would be more precise to say that I would like to determine the spread in answers that we obtain… more
Date: April 20, 2004
Creator: Cullen, D.; Blomquist, R. N.; Dean, C.; Heinrichs, D.; Kalugin, M. A.; Lee, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Calculation of Phonon Density of States for Alpha-U

Description: Phonon density of states for {alpha}-U was calculated with the linear response theory and the RSPFLAPW (fully relativistic full potential spin-polarized linearized-augmented-plane-wave) method. It has been used for studying the temperature dependence of the specific heat of uranium. It was shown that the details of the phonon DOS are not very important for the specific heat, and practically the same results can be obtained with Debye model.
Date: April 1, 2004
Creator: Kutepov, A
Partner: UNT Libraries Government Documents Department
open access

THE CLEANING OF 303 STAINLESS STEEL

Description: The sulfur found on the surfaces of stainless steel 303 (SS303) after nitric acid passivation originated from the MnS inclusions in the steel. The nitric acid attacked and dissolved these MnS inclusions, and redeposited micron-sized elemental sulfur particles back to the surface. To develop an alternative passivation procedure for SS303, citric and phosphoric acids have been evaluated. The experimental results show neither acid causes a significant amount of sulfur deposit. Thus, these two acid… more
Date: April 20, 2004
Creator: Shen, T H
Partner: UNT Libraries Government Documents Department
open access

Distribution of incoherent space - Charge tune shift of a bi-Gaussian beam

Description: The incoherent space-charge self-force tune shift of a bi-Gaussian coasting beam is revisited. The distribution density of the incoherent horizontal or vertical space-charge tune shift is computed numerically using a statistical method. Analytic approach has also been made with approximation. The results show a broad peak centered about 0.633 with a rms spread 0.168 of the linear space-charge tune shift.
Date: April 1, 2004
Creator: Ng, K. Y.
Partner: UNT Libraries Government Documents Department
open access

Quantifying the effects of limited CO2 fertilization on future climate

Description: The response of the land biosphere to the ongoing increase in atmospheric CO{sub 2} is not fully understood. To evaluate the approximate upper and lower limits of land sequestration of carbon, we performed simulations using a comprehensive carbon-climate model. In one case the land biosphere is vigorously fertilized by added CO{sub 2} and sequesters carbon throughout the 21st century. In a second case, CO{sub 2} fertilization saturates in year 2000; in this case the land becomes an additional s… more
Date: April 6, 2004
Creator: Erickson, D.; Govindasamy, B.; Caldeira, K.; Mirin, A.; Thompson, S. L.; Delire, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Nuclear Energy Research Initiative Annual Report-Innovative Approaches to Automating QA/QC of Fuel Particle Production Using On-Line Nondestructive Methods for Higher Reliability.

Description: This document summarizes the activities performed and progress made in FY-03. Various approaches for automating the particle fuel production QC process using on-line nondestructive methods for higher reliability were evaluated. In this first-year of a three-year project, surrogate fuel particles made available for testing included leftovers from initial coater development runs. These particles had a high defect fraction and the particle properties spanned a wide range, providing the opportunity… more
Date: April 20, 2004
Creator: Hockey, Ronald L.; Bond, Leonard J.; Ahmed, Salahuddin; Sandness, Gerald A.; Gray, Joseph N.; Batishko, Charles R. et al.
Partner: UNT Libraries Government Documents Department
open access

Probabilistic Seismic Hazard Analysis for Southern California Coastal Facilities

Description: The overall objective of this study was to develop probabilistic seismic hazard estimates for the coastal and offshore area of Ventura, Los Angeles and Orange counties for use as a basis for the University of Southern California (USC) to develop physical models of tsunami for the coastal regions and by the California State Lands Commission (SLC) to develop regulatory standards for seismic loading and liquefaction evaluation of marine oil terminals. The probabilistic seismic hazard analysis (PSH… more
Date: April 16, 2004
Creator: Savy, J & Foxall, B
Partner: UNT Libraries Government Documents Department
open access

Neutrons and Granite: Transport and Activation

Description: In typical ground materials, both energy deposition and radionuclide production by energetic neutrons vary with the incident particle energy in a non-monotonic way. We describe the overall balance of nuclear reactions involving neutrons impinging on granite to demonstrate these energy-dependencies. While granite is a useful surrogate for a broad range of soil and rock types, the incorporation of small amounts of water (hydrogen) does alter the balance of nuclear reactions.
Date: April 13, 2004
Creator: Bedrossian, P J
Partner: UNT Libraries Government Documents Department
open access

Resolving Nuclear Reactor Lifetime Extension Questions: A Combined Multiscale Modeling and Positron Characterization approach

Description: The objective of this work is to determine the chemical composition of nanometer precipitates responsible for irradiation hardening and embrittlement of reactor pressure vessel steels, which threaten to limit the operating lifetime of nuclear power plants worldwide. The scientific approach incorporates computational multiscale modeling of radiation damage and microstructural evolution in Fe-Cu-Ni-Mn alloys, and experimental characterization by positron annihilation spectroscopy and small angle … more
Date: April 6, 2004
Creator: Wirth, B.; Asoka-Kumar, P.; Denison, A.; Glade, S.; Howell, R.; Marian, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Pacific Northwest National Laboratory Institutional Plan FY 2004-2008

Description: This Institutional Plan for FY 2004-2008 is the principal annual planning document submitted to the Department of Energy's Office of Science by Pacific Northwest National Laboratory in Richland, Washington. This plan describes the Laboratory's mission, roles, and technical capabilities in support of Department of Energy priorities, missions, and plans. It also describes the Laboratory strategic plan, key planning assumptions, major research initiatives, and program strategy for fundamental scie… more
Date: April 15, 2004
Creator: Quadrel, Marilyn J.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen