School Meal Programs: Few Outbreaks of Foodborne Illness Reported (open access)

School Meal Programs: Few Outbreaks of Foodborne Illness Reported

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the safety of foods served in the National School Lunch and School Breakfast programs, focusing on the extent: (1) of foodborne illness outbreaks related to meals served in schools; (2) to which Department of Agriculture (USDA)-donated foods in schools were removed, replaced, or disposed of because of the potential to cause foodborne illness; and (3) to which USDA has established procurement policies and procedures for ensuring the safety of foods it donates to the programs."
Date: February 22, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Police Corps: Some Problems Resolved, But Most Positions Remain Unfilled (open access)

Police Corps: Some Problems Resolved, But Most Positions Remain Unfilled

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Justice's (DOJ) implementation of the Police Corps program under the Community Oriented Policing Services (COPS) office and, more recently, the Office of Justice Programs."
Date: February 22, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Defense Inventory: Plan to Improve Management of Shipped Inventory Should Be Strengthened (open access)

Defense Inventory: Plan to Improve Management of Shipped Inventory Should Be Strengthened

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Department of Defense's (DOD) plan for tracking inventory shipments, focusing on whether the plan: (1) responds to the provisions of the Strom Thurmond National Defense Authorization Act for Fiscal Year 1999; (2) contains the management elements needed for guiding effective implementation; and (3) adequately addresses other underlying weaknesses that led to ineffective control of inventory shipments."
Date: February 22, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: JC-184 (open access)

Texas Attorney General Opinion: JC-184

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John Cornyn, regarding a legal question submitted for clarification: Whether a municipal utility district may employ the spouse of a board member in a paid position (RQ-0111-JC)
Date: February 22, 2000
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Veterans' Issues in the 106th Congress (open access)

Veterans' Issues in the 106th Congress

None
Date: February 22, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of short pulse laser pumped x-ray lasers (open access)

Development of short pulse laser pumped x-ray lasers

X-ray lasers have been extensively studied around the world since the first laboratory demonstration on the Novette laser at LLNL in 1984. The characteristic properties of short wavelength, high monochromaticity, collimation and coherence make x-ray lasers useful for various applications. These include demonstrations of biological imaging within the water window, interferometry of laser plasmas and radiography of laser-heated surfaces. One of the critical issues has been the high power pump required to produce the inversion. The power scaling as a function of x-ray laser wavelength follows a {approx} {lambda}{sup -4} to {approx} {lambda}{sup -6} law. The shortest x-ray laser wavelength of {approx}35 {angstrom} demonstrated for Ni-like Au was at the limit of Nova laser capabilities. By requiring large, high power lasers such as Nova, the shot rate and total number of shots available have limited the rapid development of x-ray lasers and applications. In fact over the last fifteen years the main thrust has been to develop more efficient, higher repetition rate x-ray lasers that can be readily scaled to shorter wavelengths. The recent state of progress in the field can be found in references. The objective of the project was to develop a soft x-ray laser (XRL) pumped by …
Date: February 22, 2000
Creator: Dunn, J; Osterheld, A L; Hunter, J R & Shlyaptsev, V N
Object Type: Report
System: The UNT Digital Library
Quantum mechanical cluster calculations of critical scintillationprocesses (open access)

Quantum mechanical cluster calculations of critical scintillationprocesses

This paper describes the use of commercial quantum chemistrycodes to simu-late several critical scintillation processes. The crystalis modeled as a cluster of typically 50 atoms embedded in an array oftypically 5,000 point charges designed to reproduce the electrostaticfield of the infinite crystal. The Schrodinger equation is solved for theground, ionized, and excited states of the system to determine the energyand electron wavefunction. Computational methods for the followingcritical processes are described: (1) the formation and diffusion ofrelaxed holes, (2) the formation of excitons, (3) the trapping ofelectrons and holes by activator atoms, (4) the excitation of activatoratoms, and (5) thermal quenching. Examples include hole diffusion in CsI,the exciton in CsI, the excited state of CsI:Tl, the energy barrier forthe diffusion of relaxed holes in CaF2 and PbF2, and prompt hole trappingby activator atoms in CaF2:Eu and CdS:Te leading to an ultra-fast (<50ps) scintillation risetime.
Date: February 22, 2000
Creator: Derenzo, Stephen E.; Klintenberg, Mattias K. & Weber, Marvin J.
Object Type: Article
System: The UNT Digital Library
AZ-101 Mixer Pump Demonstration and Tests Data Management Analysis Plan (open access)

AZ-101 Mixer Pump Demonstration and Tests Data Management Analysis Plan

This document provides a plan for the analysis of the data collected during the AZ-101 Mixer Pump Demonstration and Tests. This document was prepared after a review of the AZ-101 Mixer Pump Test Plan (Revision 4) [1] and other materials. The plan emphasizes a structured and well-ordered approach towards handling and examining the data. This plan presumes that the data will be collected and organized into a unified body of data, well annotated and bearing the date and time of each record. The analysis of this data will follow a methodical series of steps that are focused on well-defined objectives. Section 2 of this plan describes how the data analysis will proceed from the real-time monitoring of some of the key sensor data to the final analysis of the three-dimensional distribution of suspended solids. This section also identifies the various sensors or sensor systems and associates them with the various functions they serve during the test program. Section 3 provides an overview of the objectives of the AZ-101 test program and describes the data that will be analyzed to support that test. The objectives are: (1) to demonstrate that the mixer pumps can be operated within the operating requirements; (2) …
Date: February 22, 2000
Creator: Douglas, D. G.
Object Type: Report
System: The UNT Digital Library
''Self-Smoothing of Laser Light in Plasmas''. (open access)

''Self-Smoothing of Laser Light in Plasmas''.

The modification of the optical characteristics of a laser beam by a plasma is a key issue in laser-plasma coupling. it is critical to understand how this takes place, if we are ever to understand the interaction processes in the plasma corona as well as the coupling at super-high intensities--as when laser pulses approach Petawatt intensities. Interpreting and understanding parametric instabilities in laser-produced plasmas has been a problem of increasing complexity. Improvements in diagnostic capabilities in experimental studies, as well as refinements in the modeling (using different numerical techniques), are showing a complex scenario: strong interplay among instabilities, modification of the plasma conditions caused by the instabilities, and modification to the initial distribution of laser intensity inside the plasma. Of particular interest are stimulated Brillouin scattering (SBS) and stimulated Raman scattering (SRS), instabilities which have been studied extensively during the past 20 years, both theoretically and experimentally. Until now, most studies--mainly driven by requirements associated with inertial confinement fusion (ICF)--have concentrated on backscattering instabilities. The role of forward instabilities has not received much attention, despite having the potentials for strongly modifying the overall laser-plasma interaction region. The objective of this project is to study numerically the nonlinear enhancement of large-angle, …
Date: February 22, 2000
Creator: Baldis, H. A.; Rozmus, W.; Labaune, C.; Cohen, B. & Bergen, R.
Object Type: Report
System: The UNT Digital Library
Enhanced Ultrasonic Characterization of Assemblies,TLL{_}9 (open access)

Enhanced Ultrasonic Characterization of Assemblies,TLL{_}9

The solid state bonded joint between two components; called an autoclave bond, is critical to the performance of a weapon system. A nondestructive method to assess the integrity of these joints is needed to certify the weapon for extended life. This project is developing ultrasonic technologies for bond quality assessment. Existing ultrasonic technology easily maps totally unbonded areas in a bond line. As an example, Figure 1 is an ultrasonic image of the bondline in a tensile specimen that was taken from a surrogate autoclave bond. We enhanced this technology to quantify the mechanical properties of a bond. There are situations when a bond interface appears intact by existing inspection methods, but fails under minimal loading. We developed an ultrasonic technique to eliminate this problem and assess the durability of the bond. Our approach is based on advanced signal processing and artificial intelligence techniques that extract information from the ultrasonic signal after it interacts with the bondline. We successfully demonstrated this technique on surrogate samples. We also designed and began assembly of an ultrasonic system to evaluate weapon components. Our next step is to acquire ultrasonic data on real parts and tailor the bond classification algorithm to detect and image …
Date: February 22, 2000
Creator: Thomas, G. & Chinn, D.
Object Type: Report
System: The UNT Digital Library
Thermodynamic analysis of Thermophotovoltaic Efficiency and Power Density Tradeoffs (open access)

Thermodynamic analysis of Thermophotovoltaic Efficiency and Power Density Tradeoffs

This report presents an assessment of the efficiency and power density limitations of thermophotovoltaic (TPV) energy conversion systems for both ideal (radiative-limited) and practical (defect-limited) systems. Thermodynamics is integrated into the unique process physics of TPV conversion, and used to define the intrinsic tradeoff between power density and efficiency. The results of the analysis reveal that the selection of diode bandgap sets a limit on achievable efficiency well below the traditional Carnot level. In addition it is shown that filter performance dominates diode performance in any practical TPV system and determines the optimum bandgap for a given radiator temperature. It is demonstrated that for a given radiator temperature, lower bandgap diodes enable both higher efficiency and power density when spectral control limitations are included. The goal of this work is to provide a better understanding of the basic system limitations that will enable successful long-term development of TPV energy conversion technology.
Date: February 22, 2000
Creator: Baldasara, P. F.; Reynolds, J. E.; Charache, G. W.; DePoy, D. M.; Ballinger, C. T.; Donovan, T. et al.
Object Type: Report
System: The UNT Digital Library
Experiences with BoomerAMG:: A Parallel Algebraic Multigrid Solver and Preconditioner for Large Linear Systems (open access)

Experiences with BoomerAMG:: A Parallel Algebraic Multigrid Solver and Preconditioner for Large Linear Systems

Algebraic multigrid (AMG) is an attractive choice for solving large linear systems {Lambda}x = b on unstructured grids. While AMG is applicable as a solver for a variety of problems, its robustness may be enhanced by using it as a preconditioner for Krylov solvers, such as GMRES. The sheer size of modern problems, hundreds of millions or billions of unknowns, dictates the use of massively parallel computers. AMG consists of two phases: the setup phase, in which smaller and smaller linear systems are generated by means of linear transfer operators (interpolation and restriction); and the solve phase, which employs a smoothing operator, such as Gauss-Seidel or Jacobi relaxation. Most of these components can be parallelized in a straightforward fashion; however, the coarse-grid selection, in which the grid for a smaller linear system is created on which the error can be approximated, is highly sequential. It is important to develop parallel coarsening techniques. They briefly present here the coarsening algorithms used in the parallel AMG code ''Boomer AMG'' and summarize some performance results for those algorithms. A detailed discussion of the algorithms and numerical results will be found.
Date: February 22, 2000
Creator: Hensor, V E & Yang, U M
Object Type: Article
System: The UNT Digital Library
Innovative Confinement Concepts Workshop 2000 (Book ofAbstracts) (open access)

Innovative Confinement Concepts Workshop 2000 (Book ofAbstracts)

None
Date: February 22, 2000
Creator: Celata, Christine & Staff, Accelerator and Fusion Research
Object Type: Article
System: The UNT Digital Library
Sample push out fixture (open access)

Sample push out fixture

This invention generally relates to the remote removal of pelletized samples from cylindrical containment capsules. V-blocks are used to receive the samples and provide guidance to push out rods. Stainless steel liners fit into the v-channels on the v-blocks which permits them to be remotely removed and replaced or cleaned to prevent cross contamination between capsules and samples. A capsule holder securely holds the capsule while allowing manual up/down and in/out movement to align each sample hole with the v-blocks. Both end sections contain identical v-blocks; one that guides the drive out screw and rods or manual push out rods and the other to receive the samples as they are driven out of the capsule.
Date: February 22, 2000
Creator: Biernat, John L.
Object Type: Patent
System: The UNT Digital Library
Real-Time Local Range On-Demand and Dynamic Regional Range Images (open access)

Real-Time Local Range On-Demand and Dynamic Regional Range Images

This paper presents a new approach to a gesture tracking system using real-time range on-demand. The system represents a gesture-controlled interface for interactive visual exploration of large data sets. The paper describes a method performing range processing only when necessary and where necessary. Range data is processed only for non-static regions of interest. This is accomplished by a set of filters on the color, motion, and range data. The speedup achieved is between 41% and 54%. The algorithm also includes a robust skin color segmentation insensitive to illumination changes. Selective range processing results in dynamic regional range images (DRRIs). This development is also placed in a broader context of a biological visual system emulation, specifically redundancies and attention mechanisms.
Date: February 22, 2000
Creator: Tsap, L.V.
Object Type: Article
System: The UNT Digital Library
Oblique Stimulated Raman Scattering of a Short Laser Pulse in a Plasma Channel (open access)

Oblique Stimulated Raman Scattering of a Short Laser Pulse in a Plasma Channel

The spatiotemporal evolution of parametric instabilities such as stimulated Raman scattering is studied analytically in time and two spatial dimensions. Initial and boundary conditions are chosen to represent the entrance, propagation, and exit of a laser pulse of finite extent as it progresses through a homogeneous collisional plasma channel. For most scattering angles daughter wave growth is enhanced by lateral reflections within the channel. At late times the two-dimensional interaction approaches a one-dimensional damped mode in which the dissipative loss from lateral transmission of the Stokes wave through the channel boundaries is equivalent to an overall damping of the Stokes amplitudes within the channel.
Date: February 22, 2000
Creator: Turano, E. J. & McKinstrie, C. J.
Object Type: Report
System: The UNT Digital Library
Dissipated power measurements in the A0 SRF cavity system (open access)

Dissipated power measurements in the A0 SRF cavity system

Fermilab operates a single TESLA 9-cell superconducting RF cavity in support of a photoelectron R and D beam line. Power going into the 1.8K cryogenic system via static heat leak and RF dissipation is measured from the rate of rise of the pressure in the helium bath. This paper describes the techniques used to determine the cryostat heat load and the RF performance of the cavity. A photo-injector has been constructed at Fermilab to produce a low-energy (14--18 MeV) electron beam with high charge per bunch (8 nC), short bunch length (1 mm RMS), and small transverse emittance (&lt;20 mm mrad). The facility was used to commission a photo-cathode RF gun for the TESLA Test Facility (TTF) Linac at DESY. At present, the Fermilab machine is being used for R and D in bunch length compression and fast beam diagnostics; experiments in plasma wake field acceleration and channeling acceleration are in preparation.
Date: February 22, 2000
Creator: Fuerst, J. D. & Hartung, W. H.
Object Type: Article
System: The UNT Digital Library
Method for Sampling Alpha-Helical Protein Backbones (open access)

Method for Sampling Alpha-Helical Protein Backbones

We present a novel technique of sampling the configurations of helical proteins. Assuming knowledge of native secondary structure, we employ assembly rules gathered from a database of existing structures to enumerate the geometrically possible 3-D arrangements of the constituent helices. We produce a library of possible folds for 25 helical protein cores. In each case the method finds significant numbers of conformations close to the native structure. In addition we assign coordinates to all atoms for 4 of the 25 proteins. In the context of database driven exhaustive enumeration our method performs extremely well, yielding significant percentages of structures (0.02%--82%) within 6A of the native structure. The method's speed and efficiency make it a valuable contribution towards the goal of predicting protein structure.
Date: February 22, 2000
Creator: Fain, Boris & Levitt, Michael
Object Type: Article
System: The UNT Digital Library
Collective motion sampling in proteins and DNA (open access)

Collective motion sampling in proteins and DNA

None
Date: February 22, 2000
Creator: Fain, Dr. Boris
Object Type: Report
System: The UNT Digital Library
Proceedings of the US-LHC collaboration meeting on accelerator physics experiments for future hadron colliders (open access)

Proceedings of the US-LHC collaboration meeting on accelerator physics experiments for future hadron colliders

None
Date: February 22, 2000
Creator: Fischer, W. & Pilat, F.
Object Type: Report
System: The UNT Digital Library
Nuclear Energy Research Initiative (NERI) Program. 2nd Quarterly Technical Progress Report (open access)

Nuclear Energy Research Initiative (NERI) Program. 2nd Quarterly Technical Progress Report

The research activities have been underway. We have located a large body of source material from aerospace, shipbuilding and manufacturing businesses that is serving the basis for identifying improvement methodologies. Our work on developing the three models proposed to capture the extent of the improvement possibilities has been ongoing.
Date: February 22, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
New CDF end-plug calorimeter (open access)

New CDF end-plug calorimeter

The performance of the CDF end-plug calorimeter is described. The authors determined the energy resolutions to be {sigma}/{Epsilon} = 14.5%/{radical}{Epsilon} {circle{underscore}plus} 0.7% for electron and {sigma}/{Epsilon} = 68.0%/{radical}{Epsilon} {circle{underscore}plus} 4.1% for charged pion, where {Epsilon} is the energy measured in GeV. The response linearities satisfied their requirements. The response variations on the surface of a typical tower were measured to be 2.3% for e{sup +} and 1.6% for {pi}{sup +}. For the photon conversion detection by the preshower detector, they obtained the detection efficiency for two minimum ionizing particles to be 90--100% for the phototube gains of (1--4) x 10{sup 5}. The rate of {pi}{sup +'s} depositing large fractions of energy in the electromagnetic section could be reduced by factors of 1.4--2.0 with keeping 95% efficiency for e{sup +}.
Date: February 22, 2000
Creator: Oishi, R.
Object Type: Article
System: The UNT Digital Library