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Assessing Terrorist Motivations for Attacking Critical "Chemical" Infrastructure (open access)

Assessing Terrorist Motivations for Attacking Critical "Chemical" Infrastructure

Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security, and way of life. One particular type of CI--that relating to chemicals--constitutes both an important element of our nation's infrastructure and a particularly attractive set of potential targets. This is primarily because of the large quantities of toxic industrial chemicals (TICs) it employs in various operations and because of the essential economic functions it serves. This study attempts to minimize some of the ambiguities that presently impede chemical infrastructure threat assessments by providing new insight into the key motivational factors that affect terrorist organizations propensity to attack chemical facilities. Prepared as a companion piece to the Center for Nonproliferation Studies August 2004 study--''Assessing Terrorist Motivations for Attacking Critical Infrastructure''--it investigates three overarching research questions: (1) why do terrorists choose to attack chemical-related infrastructure over other targets; (2) what specific factors influence their target selection decisions concerning chemical facilities; and (3) which, if any, types of groups are most inclined to attack chemical infrastructure targets? The study involved a multi-pronged research design, which made use of four discrete investigative techniques to answer the above questions as comprehensively as possible. These include: (1) a review of terrorism and threat …
Date: December 14, 2004
Creator: Ackerman, G.; Bale, J. & Moran, K.
Object Type: Report
System: The UNT Digital Library
Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event (open access)

Top physics: measurement of the tt-bar production cross section in pp-bar collisions at s**(1/2) = 1.96 tev using dilepton event

We report a measurement of the t{bar t} production cross section using dilepton events with jets and missing transverse energy in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a 197 {+-} 12 pb{sup -1} data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the standard model and find good agreement. The combined result of the two techniques yields a t{bar t} production cross section of 7.0{sub -2.1}{sup +2.4}(stat){sub -1.1}{sup _1.6}(syst) {+-} 0.4(lum) pb.
Date: October 14, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Top physics: search for anomalous kinematics in t anti-t dilepton events at cdf ii (open access)

Top physics: search for anomalous kinematics in t anti-t dilepton events at cdf ii

We report on a search for anomalous kinematics of t{bar t} dilepton events in p{bar p} collisions at {radical}s = 1.96 TeV using 193 pb{sup -1} of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0-4.5%.
Date: December 14, 2004
Creator: Acosta, D.
Object Type: Report
System: The UNT Digital Library
Criticality Model (open access)

Criticality Model

The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms …
Date: September 14, 2004
Creator: Alsaed, A.
Object Type: Report
System: The UNT Digital Library
House Committee on Standards of Official Conduct: A Brief History of Its Evolution and Jurisdiction (open access)

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

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
Object Type: Report
System: The UNT Digital Library
Selected Privileges and Courtesies Extended to Departing and Former Senators (open access)

Selected Privileges and Courtesies Extended to Departing and Former Senators

This report provides information on selected privileges and courtesies (with the exception of federal health insurance, life insurance, and retirement benefits) extended to departing and former Senators. Some are derived from law and Senate Rules, but most are courtesies that have been extended as a matter of custom.
Date: September 14, 2004
Creator: Amer, Mildred
Object Type: Report
System: The UNT Digital Library
Ion charge state fluctuations in vacuum arcs (open access)

Ion charge state fluctuations in vacuum arcs

Ion charge state distributions of cathodic vacuum arcs have been investigated using a modified time-of-flight method. Experiments have been done in double gate and burst gate mode, allowing us to study both systematic and stochastic changes of ion charge state distributions with a time resolution down to 100 ns. In the double gate method, two ion charge spectra are recorded with a well-defined time between measurements. The elements Mg, Bi, and Cu were selected for tests, representing metals of very different properties. For all elements it was found that large stochastic changes occur even at the limit of resolution. This is in agreement with fast changing arc properties observed elsewhere. Correlation of results for short times between measurements was found but it is argued that this is due to velocity mixing rather than due to cathode processes. The burst mode of time-of-flight measurements revealed the systematic time evolution of ion charge states within a single arc discharge, as opposed to previous measurements that relied on data averaged over many pulses. The technique shows the decay of the mean ion charge state as well as the level of material-dependent fluctuations.
Date: December 14, 2004
Creator: Anders, Andre; Fukuda, Kentaro & Yushkov, Georgy Yu
Object Type: Article
System: The UNT Digital Library
GAP Final Technical Report 12-14-04 (open access)

GAP Final Technical Report 12-14-04

The Genomics Annotation Platform (GAP) was designed to develop new tools for high throughput functional annotation and characterization of protein sequences and structures resulting from genomics and structural proteomics, benchmarking and application of those tools. Furthermore, this platform integrated the genomic scale sequence and structural analysis and prediction tools with the advanced structure prediction and bioinformatics environment of ICM. The development of GAP was primarily oriented towards the annotation of new biomolecular structures using both structural and sequence data. Even though the amount of protein X-ray crystal data is growing exponentially, the volume of sequence data is growing even more rapidly. This trend was exploited by leveraging the wealth of sequence data to provide functional annotation for protein structures. The additional information provided by GAP is expected to assist the majority of the commercial users of ICM, who are involved in drug discovery, in identifying promising drug targets as well in devising strategies for the rational design of therapeutics directed at the protein of interest. The GAP also provided valuable tools for biochemistry education, and structural genomics centers. In addition, GAP incorporates many novel prediction and analysis methods not available in other molecular modeling packages. This development led to signing …
Date: December 14, 2004
Creator: Andrew J. Bordner, PhD, Senior Research Scientist
Object Type: Report
System: The UNT Digital Library
Classroom HVAC: Improving ventilation and saving energy -- field study plan (open access)

Classroom HVAC: Improving ventilation and saving energy -- field study plan

The primary goals of this research effort are to develop, evaluate, and demonstrate a very practical HVAC system for classrooms that consistently provides classrooms (CRs) with the quantity of ventilation in current minimum standards, while saving energy, and reducing HVAC-related noise levels. This research is motivated by the public benefits of energy efficiency, evidence that many CRs are under-ventilated, and public concerns about indoor environmental quality in CRs. This document provides a summary of the detailed plans developed for the field study that will take place in 2005 to evaluate the energy and IAQ performance of a new classroom HVAC technology. The field study will include measurements of HVAC energy use, ventilation rates, and IEQ conditions in 10 classrooms with the new HVAC technology and in six control classrooms with a standard HVAC system. Energy use and many IEQ parameters will be monitored continuously, while other IEQ measurements will be will be performed seasonally. Continuously monitored data will be remotely accessed via a LonWorks network. Instrument calibration plans that vary with the type of instrumentation used are established. Statistical tests will be employed to compare energy use and IEQ conditions with the new and standard HVAC systems. Strengths of this …
Date: October 14, 2004
Creator: Apte, Michael G.; Faulkner, David; Hodgson, Alfred T. & Sullivan, Douglas P.
Object Type: Report
System: The UNT Digital Library
MONOSODIUM TITANATE MULTI-STRIKE TESTING (open access)

MONOSODIUM TITANATE MULTI-STRIKE TESTING

Research over the past decade has studied the adsorption of plutonium and uranium onto monosodium titanate (MST) in alkaline solutions. Tests showed that MST would remove the targeted radionuclides from simulated alkaline waste. Testing also indicated that Pu removal kinetics and Np capacity of the MST material impacts the size of equipment and waste blending plans for the Salt Waste Processing Facility (SWPF). Additionally, calculations suggested the baseline MST process may not achieve the desired decontamination in wastes containing elevated concentrations of Pu and Np. In this task, the authors investigated the performance of non-baseline process parameters and their effectiveness for treating waste feed in the Salt Waste Processing Facility. The work addresses a DOE request in support of technical needs expressed, in part, by the Engineering, Procurement, and Construction Contractors for the Salt Waste Processing Facility. The work investigated the effect of increased MST addition (up to 1.2 g/L) and the benefit of extra filtration steps with multiple additions of MST to salt waste containing actinides and strontium. Both simulant and actual waste testing occurred. Actual waste tests used a Tank 39H composite waste solution. In addition, testing to determine desorption of actinides from residual MST occurred. The release …
Date: July 14, 2004
Creator: BARNES, MARKJ
Object Type: Report
System: The UNT Digital Library
Involvement of Linear Plasmids in Aerobic Biodegradation of Vinyl Chloride (open access)

Involvement of Linear Plasmids in Aerobic Biodegradation of Vinyl Chloride

Pseudomonas putida strain AJ and Ochrobactrum strain TD were isolated from hazardous waste sites based on their ability to use vinyl chloride (VC) as a sole source of carbon and energy under aerobic conditions. Strains AJ and TD also use ethene and ethylene oxide as growth substrates. Strain AJ contained a linear megaplasmid (approximately 260 kb) when grown on VC or ethene, but no circular plasmids. While growing on ethylene oxide, the size of the linear plasmid in strain AJ decreased to approximately 100 kb, although its ability to use VC as a substrate was retained. The linear plasmids in strain AJ were cured and its ability to consume VC, ethene, and ethylene oxide was lost following growth on a rich substrate (Luria-Bertani broth) through at least three transfers. Strain TD contained three linear plasmids, ranging in size from approximately 100 kb to 320 kb, when growing on VC or ethene. As with strain AJ, the linear plasmids in strain TD were cured following growth on Luria -Bertani broth and its ability to consume VC and ethene was lost. Further analysis of these linear plasmids may help reveal the pathway for VC biodegradation in strains AJ and TD and explain …
Date: June 14, 2004
Creator: BRIGMON, ROBINL.
Object Type: Article
System: The UNT Digital Library
Energy Policy: The Continuing Debate and Omnibus Energy Legislation (open access)

Energy Policy: The Continuing Debate and Omnibus Energy Legislation

The history of omnibus energy legislation in the 108th Congress has been protracted. The House passed the conference version of H.R. 6 on November 18, 2003. On November 21, a cloture motion to limit debate in the Senate on the H.R. 6 conference report failed (57-40). Efforts to bring the bill back to the Senate floor early in the second session were unsuccessful. Some argued that any major changes to the legislation would not be viable because of the careful regional and political compromises that were reached to get a bill out of conference and through the House. The closest consensus was that the cost of the bill had to be reduced.
Date: June 14, 2004
Creator: Bamberger, Robert L.
Object Type: Report
System: The UNT Digital Library
Production Improvement From Increased Permeability Using Engineered Biochemical Secondary Recovery Methodology in Marginal Wells of the East Texas Field (open access)

Production Improvement From Increased Permeability Using Engineered Biochemical Secondary Recovery Methodology in Marginal Wells of the East Texas Field

A regenerating biochemical mixture and organic surfactant has been applied to wells in the East Texas Field with the goal of restoring permeability, reversing formation damage, mobilizing hydrocarbons, and ultimately increasing production. Initial work in task 1 was designed to open the perforations and remove blockages of scale, asphaltene, and other corrosion debris. This was accomplished on three wells that produce from the Woodbine, and was necessary to prepare the wells for more substantial future treatments. Secondly, in task 2, two wells were treated with much larger quantities of the biochemical mixture, e.g. 25 gallons, followed by approximately 140 barrels of a 2% KCl solution that carried the active biochemical solution into the near wellbore area and into the producing reservoir. After a 7 to 10 day acclamation and reaction period, the wells were put back into production. The biochemical solution successfully broke down the scale, paraffin and other binders blocking permeability and released significant debris which was immediately produced into the flowlines and separators. Oil production was clearly improved and the removed debris was a maintenance issue until the surface equipment could be modified. Next steps include larger treatments and tracer tests to better understand the fluid flow dynamics.
Date: July 14, 2004
Creator: Bassett, R. L. & Botto, William S.
Object Type: Report
System: The UNT Digital Library
Higher Order Hard Edge End Field Effects. (open access)

Higher Order Hard Edge End Field Effects.

In most cases, nonlinearities from magnets must be properly included in tracking and analysis to properly compute quantities of interest, in particular chromatic properties and dynamic aperture. One source of nonlinearities in magnets that is often important and cannot be avoided is the nonlinearity arising at the end of a magnet due to the longitudinal variation of the field at the end of the magnet. Part of this effect is independent of the longitudinal of the end. It is lowest order in the body field of the magnet, and is the result of taking a limit as the length over which the field at the end varies approaches zero. This is referred to as a ''hard edge'' end field. This effect has been computed previously to lowest order in the transverse variables. This paper describes a method to compute this effect to arbitrary order in the transverse variables, under certain constraints.
Date: September 14, 2004
Creator: Berg, J. S.
Object Type: Article
System: The UNT Digital Library
Cost Optimization of Non-Scaling Ffag Latices for Muon Acceleration. (open access)

Cost Optimization of Non-Scaling Ffag Latices for Muon Acceleration.

Fixed Field Gradient (FFAG) accelerators are a promising idea for reducing the cost of acceleration for muon accelerators as well as other machines. This paper presents an automated method for designing these machines to certain specifications, and uses that method to find a minimum cost design. The dependence of this minimum cost on various input parameters to the system is given. The impact of the result on an FFAG design for muon acceleration is discussed.
Date: September 14, 2004
Creator: Berg, J. S. & Palmer, R. B.
Object Type: Article
System: The UNT Digital Library
Finding the Circular Magnet Aperture Which Encloses an Artitrary Number of Midplane-Centered Beam Ellipses. (open access)

Finding the Circular Magnet Aperture Which Encloses an Artitrary Number of Midplane-Centered Beam Ellipses.

In specifying the magnets for an accelerator, one must be able to determine the aperture required by the beam. In some machines, in particular FFAGs, there is a significant variation in the closed orbit and beta functions over the energy range of the machine. In addition, the closed orbit and beta functions may vary with the longitudinal position in the magnet. It is necessary to determine a magnet aperture which encloses the beam ellipses at all energies and all positions in the magnet. This paper describes a method of determining the smallest circular aperture enclosing an arbitrary number of midplane-centered ellipses.
Date: September 14, 2004
Creator: Berg, S. J.
Object Type: Article
System: The UNT Digital Library
A Component Architecture for High-Performance Scientific Computing (open access)

A Component Architecture for High-Performance Scientific Computing

The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. In the scientific computing context, component models also promote collaboration using independently developed software, thereby allowing particular individuals or groups to focus on the aspects of greatest interest to them. The CCA supports parallel and distributed computing as well as local high-performance connections between components in a language-independent manner. The design places minimal requirements on components and thus facilitates the integration of existing code into the CCA environment. The CCA model imposes minimal overhead to minimize the impact on application performance. The focus on high performance distinguishes the CCA from most other component models. The CCA is being applied within an increasing range of disciplines, including combustion research, global climate simulation, and computational chemistry.
Date: December 14, 2004
Creator: Bernholdt, D. E.; Allan, B. A.; Armstrong, R.; Bertrand, F.; Chiu, K.; Dahlgren, T. L. et al.
Object Type: Article
System: The UNT Digital Library
Raising the Level of Programming Abstraction in Scalable Programming Models (open access)

Raising the Level of Programming Abstraction in Scalable Programming Models

The complexity of modern scientific simulations combined with the complexity of the high-performance computer hardware on which they run places an ever-increasing burden on scientific software developers, with clear impacts on both productivity and performance. We argue that raising the level of abstraction of the programming model/environment is a key element of addressing this situation. We present examples of two distinctly different approaches to raising the level of abstraction of the programming model while maintaining or increasing performance: the Tensor Contraction engine, a narrowly-focused domain specific language together with an optimizing compiler; and Extended Global Arrays, a programming framework that integrates programming models dealing with different layers of the memory/storage hierarchy using compiler analysis and code transformation techniques.
Date: February 14, 2004
Creator: Bernholdt, David E.; Nieplocha, Jarek & Sadayappan, Ponnuswamy
Object Type: Article
System: The UNT Digital Library
Investigation of the Rayleigh-Taylor and Richtmyer-Meshkov instabilities (open access)

Investigation of the Rayleigh-Taylor and Richtmyer-Meshkov instabilities

Some of the major difficulties encountered in the effort to achieve nuclear fusion by means of inertial confinement arise from the unstable behavior of the interface between the shell material and the nuclear fuel which develops upon implosion of the shell by direct or indirect laser drive. The fluid flows that develop (termed the Rayleigh-Taylor (RT) and the Richtmyer-Meshkov (RM) instabilities) cause the gassified shell material to mix with the nuclear fuel, causing a reduction in energy yield or no ignition altogether. The present research program addresses the Rayleigh-Taylor and the Richtmyer-Meshkov instabilities with extensive laboratory and computational experiments. In the past year, three new activities have been initiated: a new shock tube experiment, involving the impulsive acceleration of a test gas-filled soap bubble, diagnosed with planar Mie scattering or planar induced fluorescence; a Rayleigh-Taylor experiment based on the use of a magnetorheological (MR) fluid to fix the initial shape of the interface between the MR fluid and water; and a series of computer calculations using the Raptor code (made available by Lawrence Livermore National Laboratory) to design and simulate the shock tube experiments.
Date: January 14, 2004
Creator: Bonazza, Riccardo; Anderson, Mark & Smith, Leslie
Object Type: Report
System: The UNT Digital Library
Advanced diffusion studies with isotopically controlled materials (open access)

Advanced diffusion studies with isotopically controlled materials

The use of enriched stable isotopes combined with modern epitaxial deposition and depth profiling techniques enables the preparation of material heterostructures, highly appropriate for self- and foreign-atom diffusion experiments. Over the past decade we have performed diffusion studies with isotopically enriched elemental and compound semiconductors. In the present paper we highlight our recent results and demonstrate that the use of isotopically enriched materials ushered in a new era in the study of diffusion in solids which yields greater insight into the properties of native defects and their roles in diffusion. Our approach of studying atomic diffusion is not limited to semiconductors and can be applied also to other material systems. Current areas of our research concern the diffusion in the silicon-germanium alloys and glassy materials such as silicon dioxide and ion conducting silicate glasses.
Date: November 14, 2004
Creator: Bracht, Hartmut A.; Silvestri, Hughes H. & Haller, Eugene E.
Object Type: Article
System: The UNT Digital Library
Material Property Estimation for Direct Detections of DNAPL using Integrated Ground-Penetrating Radar Velocity, Imaging and Attribute Analysis (open access)

Material Property Estimation for Direct Detections of DNAPL using Integrated Ground-Penetrating Radar Velocity, Imaging and Attribute Analysis

The focus of our work is direct detection of DNAPLs, specifically chlorinated solvents, via material property estimation from surface ground-penetrating radar (GPR) data. We combine sophisticated GPR processing methodology with quantitative attribute analysis and material property estimation to determine the location and extent of residual and/or pooled DNAPL in both the vadose and saturated zones. An important byproduct of our research is state-of-the-art imaging which allows us to pinpoint attribute anomalies, characterize stratigraphy, identify fracture zones, and locate buried objects. Implementation and verification of these methodologies will be a significant advance in GPR research and in meeting DOE's need for reliable in-situ characterization of DNAPL contamination. Chlorinated solvents have much lower electric permittivity and conductivity than water. An electrical property contrast is induced when solvents displace water in the sediment column resulting in an anomalous GPR signature. To directly identify zones of DNAPL contamination, we focus on three aspects of reflected wave behavior--propagation velocity, frequency dependent attenuation, and amplitude variation with offset (AVO). Velocity analysis provides a direct estimate of electric permittivity, attenuation analysis provides a measure of conductivity, and AVO behavior is used to estimate the permittivity ratio at a reflecting boundary. Areas of anomalously low electric permittivity and …
Date: June 14, 2004
Creator: Bradford, John; Smithson, Scott B. & Holbrook, W. Stephen
Object Type: Report
System: The UNT Digital Library
Endangered Species: Difficult Choices (open access)

Endangered Species: Difficult Choices

This report discusses various measures being considered by Congress that propose to amend the Endangered Species Act of 1973 (ESA). Major issues in recent years have focused on whether to incorporate further protection for property owners and reduce regulatory impacts, whether to increase the protection afforded listed species, or whether to modify various aspects of the ESA, such as the role of science in decision-making.
Date: June 14, 2004
Creator: Buck, Eugene H.; Corn, M. L. & Baldwin, Pamela
Object Type: Report
System: The UNT Digital Library
Charitable Choice Provisions of H.R. 7 (open access)

Charitable Choice Provisions of H.R. 7

This documents explains the House's bill of president George Bush's faith-based initiatives.
Date: June 14, 2004
Creator: Burke, Vee
Object Type: Report
System: The UNT Digital Library
An nth-order, Gaussian Energy Distribution Model for Sintering (open access)

An nth-order, Gaussian Energy Distribution Model for Sintering

Although it is well known that the rate of sintering is governed by deceleratory kinetics, it is often difficult to fit power-law and nth-order reaction models over broad time-temperature ranges. This work shows that a phenomenological model combining a reaction order with an activation energy distribution can correlate surface area as a function of sintering time and temperature over a greater range of those variables. Qualitatively, the activation energy distribution accounts the dependence of free energy on particle size and material defects, while the reaction order accounts for geometric factors such as a distribution of diffusion lengths. The model is demonstrated for sintering of hydroxyapatite using data of Bailliez and Nzihou (Chem. Eng. J. 98 (2004), 141-152).
Date: December 14, 2004
Creator: Burnham, A K
Object Type: Article
System: The UNT Digital Library