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The CDF silicon vertex trigger (open access)

The CDF silicon vertex trigger

The CDF experiment's Silicon Vertex Trigger is a system of 150 custom 9U VME boards that reconstructs axial tracks in the CDF silicon strip detector in a 15 {mu}sec pipeline. SVT's 35 {mu}m impact parameter resolution enables CDF's Level 2 trigger to distinguish primary and secondary particles, and hence to collect large samples of hadronic bottom and charm decays. We review some of SVT's key design features. Speed is achieved with custom VLSI pattern recognition, linearized track fitting, pipelining, and parallel processing. Testing and reliability are aided by built-in logic state analysis and test-data sourcing at each board's input and output, a common inter-board data link, and a universal ''Merger'' board for data fan-in/fan-out. Speed and adaptability are enhanced by use of modern FPGAs.
Date: June 23, 2003
Creator: Ashmanskas, B.; Barchiesi, A. & Bardi, A.
Object Type: Article
System: The UNT Digital Library
TECHNICAL BASIS FOR VENTILATION REQUIREMENTS IN TANK FARMS OPERATING SPECIFICATIONS DOCUMENTS (open access)

TECHNICAL BASIS FOR VENTILATION REQUIREMENTS IN TANK FARMS OPERATING SPECIFICATIONS DOCUMENTS

This report provides the technical basis for high efficiency particulate air filter (HEPA) for Hanford tank farm ventilation systems (sometimes known as heating, ventilation and air conditioning [HVAC]) to support limits defined in Process Engineering Operating Specification Documents (OSDs). This technical basis included a review of older technical basis and provides clarifications, as necessary, to technical basis limit revisions or justification. This document provides an updated technical basis for tank farm ventilation systems related to Operation Specification Documents (OSDs) for double-shell tanks (DSTs), single-shell tanks (SSTs), double-contained receiver tanks (DCRTs), catch tanks, and various other miscellaneous facilities.
Date: June 23, 2003
Creator: BERGLIN, E J
Object Type: Report
System: The UNT Digital Library
Assessing the Proliferation Resistance of Innovative Nuclear Fuel Cycles (open access)

Assessing the Proliferation Resistance of Innovative Nuclear Fuel Cycles

The National Nuclear Security Administration is developing methods for nonproliferation assessments to support the development and implementation of U.S. nonproliferation policy. This paper summarizes the key results of that effort. Proliferation resistance is the degree of difficulty that a nuclear material, facility, process, or activity poses to the acquisition of one or more nuclear weapons. A top-level measure of proliferation resistance for a fuel cycle system is developed here from a hierarchy of metrics. At the lowest level, intrinsic and extrinsic barriers to proliferation are defined. These barriers are recommended as a means to characterize the proliferation characteristics of a fuel cycle. Because of the complexity of nonproliferation assessments, the problem is decomposed into: metrics to be computed, barriers to proliferation, and a finite set of threats. The spectrum of potential threats of nuclear proliferation is complex and ranges from small terrorist cells to industrialized countries with advanced nuclear fuel cycles. Two general categories of methods have historically been used for nonproliferation assessments: attribute analysis and scenario analysis. In the former, attributes of the systems being evaluated (often fuel cycle systems) are identified that affect their proliferation potential. For a particular system under consideration, the attributes are weighted subjectively. In …
Date: June 23, 2003
Creator: Bari, R.; Roglans, J.; Denning, R. & Mladineo, S.
Object Type: Article
System: The UNT Digital Library
Neutron Detection with a Cryogenic Spectrometer (open access)

Neutron Detection with a Cryogenic Spectrometer

Cryogenic calorimeters are used for x-ray detection because of their exquisite energy resolution and have found application in x-ray astronomy, and the search for dark matter. These devices operate by detecting the heat pulse produced by ionization in an absorber cooled to temperatures below 1 K. Such temperatures are needed to lower the absorber's heat capacity to the point that the deposition of even a few eV results in a measurable temperature excursion. Typical absorbers for dark matter measurements are massive Si or Ge crystals, and, with Ge, have achieved a resolution of 650 eV at 10 keV. Chow, et al., report the measurement of the 60 keV emission from {sup 241}Am with 230 eV resolution using a superconducting tin absorber. Cunningham, et al., also using a superconducting tin absorber, have recently reported a four-fold improvement over Chow. With such results being reported from the x- and gamma-ray world it is natural to examine the possibilities for cryogenic neutron spectroscopy. Such a detector would operate by detecting the heat pulses caused by neutron capture and scattering. To date, {sup 6}LiF has been the absorber of choice because relatively large crystals can be grown, and it is an insulating material with …
Date: June 23, 2003
Creator: Bell, Z. W.; Lamberti, V. E.; Carpenter, D. A. & Cristy, S. S.
Object Type: Report
System: The UNT Digital Library
Homeland Security: Intelligence Support (open access)

Homeland Security: Intelligence Support

Legislation establishing a Department of Homeland Security includes provisions for an information analysis element within the new department. This report examines the information analysis function and the sharing of information among federal agencies but does not address provisions in the proposed legislation governing the sharing of intelligence with state and local officials.
Date: June 23, 2003
Creator: Best, Richard A., Jr.
Object Type: Report
System: The UNT Digital Library
Run II physics at the Fermilab Tevatron and advanced analysis methods (open access)

Run II physics at the Fermilab Tevatron and advanced analysis methods

The Fermilab Tevatron has the unique opportunity to explore physics at the electroweak scale with the highest ever proton-antiproton collision energy of {radical}s = 1.96 TeV and unprecedented luminosity. About 20 times more data is expected to be collected during the first phase of the collider Run II which is in its second year of data-taking. The second phase of Run II, expected to begin in 2005, will increase the integrated luminosity to about 10-15 fb{sup -1}. Discovering a low mass Higgs boson and evidence for Supersymmetry or for other new physics beyond the Standard Model are the main physics goals for Run II. It is widely recognized that the use of advanced analysis methods will be crucial to achieve these goals. I discuss the current status of Run II at the Tevatron, prospects and foreseen applications of advanced analysis methods.
Date: June 23, 2003
Creator: Bhat, Pushpalatha C
Object Type: Article
System: The UNT Digital Library
Federal Credit Reform: Implementation of the Changed Budgetary Treatment of Direct Loans and Loan Guarantees (open access)

Federal Credit Reform: Implementation of the Changed Budgetary Treatment of Direct Loans and Loan Guarantees

On November 5, 1990, the Omnibus Budget Reconciliation Act of 1990 (P.L. 101-508) was signed into law. P.L. 101-508 added Title V to the Congressional Budget Act. Title V, also called the Federal Credit Reform Act of 1990 (the FCRA), changed how the unified budget reports the cost of federal credit activities (i.e., federal direct loans and loan guarantees). Before the fiscal year 1992 (FY1992), for a given fiscal year, the budgetary cost of a new direct loan or loan guarantee was the net cash flow for that fiscal year.
Date: June 23, 2003
Creator: Bickley, James M.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 235, Ed. 1 Monday, June 23, 2003 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 235, Ed. 1 Monday, June 23, 2003

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: June 23, 2003
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Perry Daily Journal (Perry, Okla.), Vol. 110, No. 114, Ed. 1 Monday, June 23, 2003 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 110, No. 114, Ed. 1 Monday, June 23, 2003

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: June 23, 2003
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
Fishery, Aquaculture, and Marine Mammal Legislation in the 108th Congress (open access)

Fishery, Aquaculture, and Marine Mammal Legislation in the 108th Congress

This report provides the information related to the fishery, aquaculture, and marine mammal issues in the 108th Congress
Date: June 23, 2003
Creator: Buck, Eugene H.
Object Type: Report
System: The UNT Digital Library
Emission methods of experimental investigations of ion velocities in vacuum Arc plasmas (open access)

Emission methods of experimental investigations of ion velocities in vacuum Arc plasmas

None
Date: June 23, 2003
Creator: Bugaev, A. S.; Gushenets, V. I.; Nikolaev, A. G.; Oks, E. M.; Yushkov, G. Yu.; Anders, A. et al.
Object Type: Article
System: The UNT Digital Library
Antiproton stacking in the Recycler (open access)

Antiproton stacking in the Recycler

Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, June 23, 2003 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, June 23, 2003

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: June 23, 2003
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Presiding Officer: Senate (open access)

Presiding Officer: Senate

None
Date: June 23, 2003
Creator: Campbell, Colton C.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 210, Ed. 1 Monday, June 23, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 210, Ed. 1 Monday, June 23, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 23, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Electrical Resistivity as an Indicator of Saturation in Fractured Geothermal Reservoir Rocks: Experimental Data and Modeling (open access)

Electrical Resistivity as an Indicator of Saturation in Fractured Geothermal Reservoir Rocks: Experimental Data and Modeling

The electrical resistivity of rock cores under conditions representative of geothermal reservoirs is strongly influenced by the state and phase (liquid/vapor) of the pore fluid. In fractured samples, phase change (vaporization/condensation) can result in resistivity changes that are more than an order of magnitude greater than those measured in intact samples. These results suggest that electrical resistivity monitoring of geothermal reservoirs may provide a useful tool for remotely detecting the movement of water and steam within fractures, the development and evolution of fracture systems and the formation of steam caps. We measured the electrical resistivity of cores of welded tuff containing fractures of various geometries to investigate the resistivity contrast caused by active boiling and to determine the effects of variable fracture dimensions and surface area on water extraction from the matrix. We then used the Nonisothermal Unsaturated Flow and Transport model (NUFT) (Nitao, 1998) to simulate the propagation of boiling fronts through the samples. The simulated saturation profiles combined with previously reported measurements of resistivity-saturation curves allow us to estimate the evolution of the sample resistivity as the boiling front propagates into the rock matrix. These simulations provide qualitative agreement with experimental measurements suggesting that our modeling approach may …
Date: June 23, 2003
Creator: Detwiler, R. L. & Roberts, J. J.
Object Type: Article
System: The UNT Digital Library
Oral History Interview with Sam Hughes, November 15, 2001 (open access)

Oral History Interview with Sam Hughes, November 15, 2001

Interview with Lieutenant Sam Hughes, an engineer in the United States Army during the Vietnam War. Hughes goes into great detail about his experiences early on in Vietnam, including hitchhiking to Saigon after their paperwork was lost; he also answers questions and explains how his life was when he returned home from the war. Hughes ends by commenting on the current war going on in Afghanistan.
Date: June 23, 2003
Creator: Evans, Celeste & Hughes, Sam
Object Type: Text
System: The Portal to Texas History
Comparison of ELM Pulse Propagation in the DIII-D SOL and Divertors with an Ion Convection Model (open access)

Comparison of ELM Pulse Propagation in the DIII-D SOL and Divertors with an Ion Convection Model

None
Date: June 23, 2003
Creator: Fenstermacher, M. E.; Porter, G. D.; Leonard, A. W.; Brooks, N. H.; Boedo, J. A.; Colchin, R. J. et al.
Object Type: Article
System: The UNT Digital Library
Presidential Vetoes, 1789-Present: A Summary Overview (open access)

Presidential Vetoes, 1789-Present: A Summary Overview

None
Date: June 23, 2003
Creator: Galemore, Gary L.
Object Type: Report
System: The UNT Digital Library
Energy: Useful Facts and Numbers (open access)

Energy: Useful Facts and Numbers

Energy supplies and prices are a major economic factor in the United States, and energy markets are volatile and unpredictable. For both these reasons, energy policy is of frequent interest to the Congress. This report presents a statistical view of the supply and consumption of various forms of energy. After an introductory overview of aggregate energy consumption, the report presents detailed analysis of trends and statistics regarding specific energy sources: oil, electricity, natural gas, and coal. A section on trends in energy efficiency is also presented.
Date: June 23, 2003
Creator: Glover, Carol & Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
Public (BLM) Lands and National Forests (open access)

Public (BLM) Lands and National Forests

None
Date: June 23, 2003
Creator: Gorte, Ross W. & Hardy-Vincent, Carol
Object Type: Report
System: The UNT Digital Library
The Dissolution of Desicooler Residues in H-Canyon Dissolvers (open access)

The Dissolution of Desicooler Residues in H-Canyon Dissolvers

A series of dissolution and characterization studies has been performed to determine if FB-Line residues stored in desicooler containers will dissolve using a modified H-Canyon processing flowsheet. Samples of desicooler materials were used to evaluate dissolving characteristics in the low-molar nitric acid solutions used in H-Canyon dissolvers. The selection for the H-Canyon dissolution of desicooler residues was based on their high-enriched uranium content and trace levels of plutonium. Test results showed that almost all of the enriched uranium will dissolve from the desicooler materials after extended boiling in one molar nitric acid solutions. The residue that contained uranium after completion of the extended boiling cycle consisted of brown solids that had agglomerated into large pieces and were floating on top of the dissolver solution. Addition of tenth molar fluoride to a three molar nitric acid solution containing boron did not dissolve remaining uranium from the brown solids. Only after boiling in an eight molar nitric acid-tenth molar fluoride solution without boron did remaining uranium and aluminum dissolve from the brown solids. The amount of uranium associated with brown solids would be approximately 1.4 percent of the total uranium content of the desicooler materials. The brown solids that remain in the …
Date: June 23, 2003
Creator: Gray, John H.
Object Type: Report
System: The UNT Digital Library
Spectroelectrochemical Sensor for Technetium Applicable to the Vadose Zone (open access)

Spectroelectrochemical Sensor for Technetium Applicable to the Vadose Zone

The general aim of this project is to continue the design and implementation of a new sensor technology that offers the unprecedented levels of specificity needed for analysis of the complex chemical mixtures found at DOE sites nationwide. The new sensor concept combines the elements of electrochemistry, spectroscopy and selective partitioning into a single device that provides three levels of selectivity. The specific goal of this project is the development of a sensor for technetium (Tc) that is applicable to characterizing and monitoring the Vadose Zone and associated subsurface water at the Hanford site. The first goal is a sensor that determines technetium in the chemical form pertechnetate (TcO{sub 4}{sup -}). This report summarizes work during 6/16/01-6/15/02 of a three-year project that began on 9/15/99. During this period our efforts have focused on four areas that are discussed in the following sections. Electrochemistry of pertechnetate (TcO{sub 4}{sup -}) at bare ITO and film-coated ITO electrodes; Enhancing sensitivity by increasing analyte absorptivity; Development and characterization of selective films; and Improved field portable spectroelectrochemical sensor.
Date: June 23, 2003
Creator: Heineman, William R.; Seliskar, Carl J.; Bryan, Samuel A. & Hubler, Timothy L.
Object Type: Report
System: The UNT Digital Library
Electroactive Materials for Anion Separation -- Technetium from Nitrate (open access)

Electroactive Materials for Anion Separation -- Technetium from Nitrate

The aim of the proposed research is to use electroactive ion exchange materials to remove anionic contaminants from HLW wastes and process streams. An ion exchange process using electroactive materials sorbs contaminants selectively and then expels (elutes) them electrochemically by changing the charge balance through redox reactions in the sorbent as opposed to requiring the addition of a chemical eluant. Such processes can theoretically remove anions (e.g., pertechnetate, chromate, and perchorate) and concentrate them in a separate product stream while adding no process chemicals. A practical implementation in HLW process facilities would be a breakthrough in the ability of DOE to economically minimize waste and prevent pollution throughout the complex. To enable this, our work focuses on manipulating specific properties of redox polymers to control the hydrophobicity and ion-pair properties pertinent to the reversibility, selectivity, stability, intercalation/de-intercalation rates, and capacity of the polymers. Of primary focus in the immediate future is to prepare materials with greater pH stability and selectivity as our previous studies with polyvinylferrocene (PVF) polymers don't meet the material requirements for the intended application.
Date: June 23, 2003
Creator: Hubler, Timothy L.
Object Type: Report
System: The UNT Digital Library