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VA and Defense Health Care: Progress and Challenges DOD Faces in Executing a Military Medical Surveillance System (open access)

VA and Defense Health Care: Progress and Challenges DOD Faces in Executing a Military Medical Surveillance System

A statement of record issued by the General Accounting Office with an abstract that begins "The Departments of Defense (DOD) and Veterans Affairs (VA) are establishing a medical surveillance system for the health care needs of military personnel and veterans. The system will collect and analyze information on deployments, environmental health threats, disease monitoring, medical assessments, and medical encounters. GAO has identified weaknesses in DOD's medical surveillance capability and performance during the Gulf War and Operation Joint Endeavor. Investigations into the unexplained illnesses of Gulf War veterans uncovered many deficiencies in DOD's ability to collect, maintain, and transfer accurate data on the movement of troops, potential exposures to health risks, and medical incidents during deployment. DOD has several initiatives under way to improve the reliability of deployment information and to enhance its information technology capabilities, though some initiatives are several years away from full implementation. The VA's ability to serve veterans and provide backup to DOD in times of war will be enhanced as DOD increases its medical surveillance capability."
Date: October 16, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Telecommunications: Characteristics and Competitiveness of the Internet Backbone Market (open access)

Telecommunications: Characteristics and Competitiveness of the Internet Backbone Market

A letter report issued by the General Accounting Office with an abstract that begins "Although most Americans are familiar with Internet service providers that give consumers a pathway, or "on-ramp," to the Internet, few are familiar with Internet backbone providers and backbone networks. At the Internet's core are many high-capacity, long-haul "backbone" networks that route data traffic over long distances using high-speed fiber lines. Internet backbone providers compete in the marketplace and cooperate in the exchange of data traffic. The cooperative exchange of traffic among backbone providers is essential if the Internet is to remain a seamless and widely accessible public medium. Interconnection among Internet backbone providers varies both in terms of the physical structure and financial agreements of data traffic exchange. The physical structure of interconnection takes two forms: (1) the exchange of traffic among many backbone providers at a "network access point"--a common facility--and (2) the exchange of traffic between two or more backbone providers at "private" interconnection points. No publicly available data exist with which to evaluate competitiveness in the Internet backbone market. Evolution of this market is likely to be largely affected by two types of emerging services. First, demand is likely to rise for time-sensitive …
Date: October 16, 2001
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Micromechanics of Transformation Superplasticity in Ti-6Al-4V/TiBw Composites (open access)

Micromechanics of Transformation Superplasticity in Ti-6Al-4V/TiBw Composites

Transformation superplasticity is a deformation mechanism induced by thermally-cycling a polymorphic material through the phase transformation range while simultaneously applying an external biasing stress. Unlike microstructural superplasticity, which requires a fine, equiaxed grain structure, this mechanism can be applied to coarse-grained alloys and composites. In this article, we review our research on transformation superplasticity of Ti-6Al-4V/TiB-whisker reinforced composites, during thermal cycling through the titanium {alpha}/{beta} transformation range. The composites exhibit Newtonian flow and superplastic extension under these conditions. We describe the constitutive behavior of composites containing 0, 5 and 10 vol% reinforcing whiskers, and consider the effects of load transfer from matrix to whisker on superplastic deformation using existing rheological models. Additionally, strain hardening due to gradual whisker alignment is observed, and rationalized in terms of increased load transfer for aligned whiskers.
Date: October 16, 2001
Creator: Schuh, C & Dunand, D C
Object Type: Article
System: The UNT Digital Library
Data Qualification Report For: Thermodynamic Data File, DATA0.YMP.R0 For Geochemical Code, EQ3/6 (open access)

Data Qualification Report For: Thermodynamic Data File, DATA0.YMP.R0 For Geochemical Code, EQ3/6

The objective of this work is to evaluate the adequacy of chemical thermodynamic data provided by Lawrence Livermore National Laboratory (LLNL) as DataO.ymp.ROA in response to an input request submitted under AP-3.14Q. This request specified that chemical thermodynamic data available in the file, Data0.com.R2, be updated, improved, and augmented for use in geochemical modeling used in Process Model Reports (PMRs) for Engineered Barrier Systems, Waste Form, Waste Package, Unsaturated Zone, and Near Field Environment, as well as for Performance Assessment. The data are qualified in the temperature range 0 to 100 C. Several Data Tracking Numbers (DTNs) associated with Analysis/Model Reports (AMR) addressing various aspects of the post-closure chemical behavior of the waste package and the Engineered Barrier System that rely on EQ316 outputs to which these data are used as input, are Principal Factor affecting. This qualification activity was accomplished in accordance with the AP-SIII.2Q using the Technical Assessment method. A development plan, TDP-EBS-MD-000044, was prepared in accordance with AP-2.13Q and approved by the Responsible Manager. In addition, a Process Control Evaluation was performed in accordance with AP-SV.1Q. The qualification method, selected in accordance with AP-SIII.2Q, was Technical Assessment. The rationale for this approach is that the data in …
Date: October 16, 2001
Creator: Cloke, P.L.
Object Type: Report
System: The UNT Digital Library
Mixed metal films with switchable optical properties (open access)

Mixed metal films with switchable optical properties

Thin, Pd-capped metallic films containing magnesium and first row transition metals (Mn, Fe, Co) switch reversibly from their initial reflecting state to visually transparent states when exposed to gaseous hydrogen or following cathodic polarization in an alkaline electrolyte. Reversion to the reflecting state is achieved by exposure to air or by anodic polarization. The films were prepared by co-sputtering from one magnesium target and one manganese, iron, or cobalt target. Both the dynamic optical switching range and the speed of the transition depend on the magnesium-transition metal ratio. Infrared spectra of films in the transparent, hydrided (deuterided) states support the presence of the intermetallic hydride phases Mg3MnH7, Mg2FeH6, and Mg2CoH5.
Date: October 16, 2001
Creator: Richardson, Thomas J.; Slack, Jonathan L.; Farangis, Baker & Rubin, Michael D.
Object Type: Article
System: The UNT Digital Library
ON THE THEORY OF COLLISIONS BETWEEN ATOMS AND ELECTRICALLY CHARGED PARTICLES. (open access)

ON THE THEORY OF COLLISIONS BETWEEN ATOMS AND ELECTRICALLY CHARGED PARTICLES.

None
Date: October 16, 2001
Creator: White, S. N.
Object Type: Article
System: The UNT Digital Library
A decision support system for adaptive real-time management ofseasonal wetlands in California (open access)

A decision support system for adaptive real-time management ofseasonal wetlands in California

This paper describes the development of a comprehensive flow and salinity monitoring system and application of a decision support system (DSS) to improve management of seasonal wetlands in the San Joaquin Valley of California. The Environmental Protection Agency regulates salinity discharges from non-point sources to the San Joaquin River using a procedure known as the Total Maximum Daily Load (TMDL) to allocate the assimilative capacity of the River for salt among watershed sources. Management of wetland sources of salt load will require the development of monitoring systems, more integrative management strategies and coordination with other entities. To obtain local cooperation the Grassland Water District, whose primary function is to supply surface water to private duck clubs and managed wetlands, needs to communicate to local landowners the likely impacts of salinity regulation on the long term health and function of wildfowl habitat. The project described in this paper will also provide this information. The models that form the backbone of the DSS develop salinity balances at both a regional and local scale. The regional scale concentrates on deliveries to and exports from the Grasland Water District while the local scale focuses on an individual wetland unit where more intensive monitoring is …
Date: October 16, 2001
Creator: Quinn, Nigel W.T. & Hanna, W. Mark
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 324, Ed. 1 Tuesday, October 16, 2001 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 324, Ed. 1 Tuesday, October 16, 2001

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: October 16, 2001
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam Diagnostics Systems for the National Ignition Facility (open access)

Beam Diagnostics Systems for the National Ignition Facility

The National Ignition Facility (NIF) laser focuses 1.8 megajoules of ultraviolet light (wavelength 351 nanometers) from 192 beams into a 600-micrometer-diameter volume. Effective use of this output in target experiments requires that the power output from all of the beams match within 8% over their entire 20-nanosecond waveform. The scope of NIF beam diagnostics systems necessary to accomplish this task is unprecedented for laser facilities. Each beamline contains 110 major optical components distributed over a 510-meter path, and diagnostic tolerances for beam measurement are demanding. Total laser pulse energy is measured with 2.8% precision, and the interbeam temporal variation of pulse power is measured with 4% precision. These measurement goals are achieved through use of approximately 160 sensor packages that measure the energy at five locations and power at three locations along each beamline using 335 photodiodes, 215 calorimeters, and 36 digitizers. Successful operation of such a system requires a high level of automation of the widely distributed sensors. Computer control systems provide the basis for operating the shot diagnostics with repeatable accuracy, assisted by operators who oversee system activities and setup, respond to performance exceptions, and complete calibration and maintenance tasks.
Date: October 16, 2001
Creator: Demaret, R D; Boyd, R D; Bliss, E S; Gates, A J & Severyn, J R
Object Type: Article
System: The UNT Digital Library
U.S.-Jordan Free Trade Agreement: Analysis of Environmental Provisions (open access)

U.S.-Jordan Free Trade Agreement: Analysis of Environmental Provisions

None
Date: October 16, 2001
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Efficient Error Calculation for Multiresolution Texture-Based Volume Visualization (open access)

Efficient Error Calculation for Multiresolution Texture-Based Volume Visualization

Multiresolution texture-based volume visualization is an excellent technique to enable interactive rendering of massive data sets. Interactive manipulation of a transfer function is necessary for proper exploration of a data set. However, multiresolution techniques require assessing the accuracy of the resulting images, and re-computing the error after each change in a transfer function is very expensive. They extend their existing multiresolution volume visualization method by introducing a method for accelerating error calculations for multiresolution volume approximations. Computing the error for an approximation requires adding individual error terms. One error value must be computed once for each original voxel and its corresponding approximating voxel. For byte data, i.e., data sets where integer function values between 0 and 255 are given, they observe that the set of error pairs can be quite large, yet the set of unique error pairs is small. instead of evaluating the error function for each original voxel, they construct a table of the unique combinations and the number of their occurrences. To evaluate the error, they add the products of the error function for each unique error pair and the frequency of each error pair. This approach dramatically reduces the amount of computation time involved and allows …
Date: October 16, 2001
Creator: LaMar, E.; Hamann, B. & Joy, K. I.
Object Type: Article
System: The UNT Digital Library
Large-Scale CORBA-Distributed Software Framework for NIF Controls (open access)

Large-Scale CORBA-Distributed Software Framework for NIF Controls

The Integrated Computer Control System (ICCS) is based on a scalable software framework that is distributed over some 325 computers throughout the NIF facility. The framework provides templates and services at multiple levels of abstraction for the construction of software applications that communicate via CORBA (Common Object Request Broker Architecture). Various forms of object-oriented software design patterns are implemented as templates to be extended by application software. Developers extend the framework base classes to model the numerous physical control points, thereby sharing the functionality defined by the base classes. About 56,000 software objects each individually addressed through CORBA are to be created in the complete ICCS. Most objects have a persistent state that is initialized at system start-up and stored in a database. Additional framework services are provided by centralized server programs that implement events, alerts, reservations, message logging, database/file persistence, name services, and process management. The ICCS software framework approach allows for efficient construction of a software system that supports a large number of distributed control points representing a complex control application.
Date: October 16, 2001
Creator: Carey, R W; Fong, K W; Sanchez, R J; Tappero, J D & Woodruff, J P
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 102, No. 195, Ed. 1 Tuesday, October 16, 2001 (open access)

Altus Times (Altus, Okla.), Vol. 102, No. 195, Ed. 1 Tuesday, October 16, 2001

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 16, 2001
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Rains County Leader (Emory, Tex.), Vol. 114, No. 19, Ed. 1 Tuesday, October 16, 2001 (open access)

Rains County Leader (Emory, Tex.), Vol. 114, No. 19, Ed. 1 Tuesday, October 16, 2001

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: October 16, 2001
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Hot Topics in Ultra-Peripheral Ion Collisions (open access)

Hot Topics in Ultra-Peripheral Ion Collisions

Ultra-peripheral collisions of relativistic heavy ions involve long-ranged electromagnetic interactions at impact parameters too large for hadronic interactions to occur. The nuclear charges are large; with the coherent enhancement, the cross sections are also large. Many types of photonuclear and purely electromagnetic interactions are possible. We present here an introduction to ultra-peripheral collisions, and present four of the most compelling physics topics.
Date: October 16, 2001
Creator: Baur, G.; Bertulani, C. A.; Chiu, M.; Ginzburg, I. F.; Hencken, K.; Klein, S. R. et al.
Object Type: Article
System: The UNT Digital Library
Femtosecond x-rays from relativistic electrons: New tools for probing structural dynamics (open access)

Femtosecond x-rays from relativistic electrons: New tools for probing structural dynamics

None
Date: October 16, 2001
Creator: Schoenlein, R. W.; Chong, H. H. W.; Glover, T. E.; Heimann, P. A.; Leemans, W. P.; Padmore, H. A. et al.
Object Type: Article
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 28, Ed. 1 Tuesday, October 16, 2001 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 28, Ed. 1 Tuesday, October 16, 2001

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: October 16, 2001
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Stiff Temperature Profiles in JT-60U ELMy H-mode Plasmas (open access)

Stiff Temperature Profiles in JT-60U ELMy H-mode Plasmas

The 'stiffness' of thermal transport in ELMy H-modes [edge localized high-confinement modes] is examined in a series of carefully chosen JT-60U plasmas, and measured temperatures are compared with the predictions of several transport models. A heating power scan with constant T(subscript ''ped''), a scan of pedestal temperature, T(subscript ''ped''), with constant heating power, and an on-axis/off-axis heating comparison are presented. In the power scan a 45% increase in heating (and a 12% density rise) produces an approximately fixed core temperature profile in a group of five plasmas with the same pedestal temperature. With fixed heating power, we find that a 30-40% increase in T(subscript ''ped'') is associated with similar increases in core temperature. Heating in the deep core is varied by employing different groups of neutral beams that deposit their power near the magnetic axis and farther from the axis. In these plasmas, on-axis heating produces slightly more peaked temperature profiles, although they have 60% more heating power inside r = a/2. Transport models are tested by solving the power balance equations to predict temperatures, which are then compared to the measurements. Predictions of the RLWB and IFS/PPPL models generally agree with the measured temperatures outside r approximately 0.3a, but …
Date: October 16, 2001
Creator: Mikkelsen, D.R.; Urano, H.; Shirai, H.; Takizuka, T.; Kamada, Y.; Hatae, T. et al.
Object Type: Report
System: The UNT Digital Library
The Alpha Dynamo Effects in Laboratory Plasmas (open access)

The Alpha Dynamo Effects in Laboratory Plasmas

A concise review of observations of the alpha dynamo effect in laboratory plasmas is given. Unlike many astrophysical systems, the laboratory pinch plasmas are driven magnetically. When the system is overdriven, the resultant instabilities cause magnetic and flow fields to fluctuate, and their correlation induces electromotive forces along the mean magnetic field. This alpha-effect drives mean parallel electric current, which, in turn, modifies the initial background mean magnetic structure towards the stable regime. This drive-and-relax cycle, or the so-called self-organization process, happens in magnetized plasmas in a timescale much shorter than resistive diffusion time, thus it is a fast and unquenched dynamo process. The observed alpha-effect redistributes magnetic helicity (a measure of twistedness and knottedness of magnetic field lines) but conserves its total value. It can be shown that fast and unquenched dynamos are natural consequences of a driven system where fluctuations are statistically either not stationary in time or not homogeneous in space, or both. Implications to astrophysical phenomena will be discussed.
Date: October 16, 2001
Creator: Ji, Hantao & Prager, Stewart C.
Object Type: Report
System: The UNT Digital Library
CDF results on diffraction from Run I and plans for Run II (open access)

CDF results on diffraction from Run I and plans for Run II

Results on soft and hard diffraction obtained by the CDF Collaboration in Run I of the Fermilab Tevatron {bar p}p collider are reviewed and compared with results from the DESY ep collider HERA and with theoretical expectations. In addition, the CDF program for diffractive studies in Run II is briefly reviewed with emphasis on the relevant detector upgrades and physics goals.
Date: October 16, 2001
Creator: Goulianos, K.
Object Type: Article
System: The UNT Digital Library
SiC-BASED HYDROGEN SELECTIVE MEMBRANES FOR WATER-GAS-SHIFT REACTION (open access)

SiC-BASED HYDROGEN SELECTIVE MEMBRANES FOR WATER-GAS-SHIFT REACTION

This technical report summarizes our activities conducted in Yr II. In Yr I we successfully demonstrated the feasibility of preparing the hydrogen selective SiC membrane with a chemical vapor deposition (CVD) technique. In addition, a SiC macroporous membrane was fabricated as a substrate candidate for the proposed SiC membrane. In Yr II we have focused on the development of a microporous SiC membrane as an intermediate layer between the substrate and the final membrane layer prepared from CVD. Powders and supported thin silicon carbide films (membranes) were prepared by a sol-gel technique using silica sol precursors as the source of silicon, and phenolic resin as the source of carbon. The powders and films were prepared by the carbothermal reduction reaction between the silica and the carbon source. The XRD analysis indicates that the powders and films consist of SiC, while the surface area measurement indicates that they contain micropores. SEM and AFM studies of the same films also validate this observation. The powders and membranes were also stable under different corrosive and harsh environments. The effects of these different treatments on the internal surface area, pore size distribution, and transport properties, were studied for both the powders and the membranes …
Date: October 16, 2001
Creator: Liu, Paul K.T.
Object Type: Report
System: The UNT Digital Library
Parametric Investigations of Miniaturized Cylindrical and Annular Hall Thrusters (open access)

Parametric Investigations of Miniaturized Cylindrical and Annular Hall Thrusters

A cylindrical geometry Hall thruster may overcome certain physical and technological limitations in scaling down of Hall thrusters to miniature sizes. The absence of the inner wall and use of the cusp magnetic field can potentially reduce heating of the thruster parts and erosion of the channel. A 2.6 cm miniaturized Hall thruster of a flexible design was built and successfully operated in the power range of 50-300 W. Comparison of preliminary results obtained for cylindrical and annular thruster configurations is presented.
Date: October 16, 2001
Creator: Smirnov, A.; Raitses, Y. & Fisch, N. J.
Object Type: Article
System: The UNT Digital Library
Measurements of Plasma Potential Distribution in Segmented Electrode Hall Thruster (open access)

Measurements of Plasma Potential Distribution in Segmented Electrode Hall Thruster

Use of a segmented electrode placed at the Hall thruster exit can substantially reduce the voltage potential drop in the fringing magnetic field outside the thruster channel. In this paper, we investigate the dependence of this effect on thruster operating conditions and segmented electrode configuration. A fast movable emissive probe is used to measure plasma potential in a 1 kW laboratory Hall thruster with semented electrodes made of a graphite material. Relatively small probe-induced perturbations of the thruster discharge in the vicinity of the thruster exit allow a reasonable comparison of the measured results for different thruster configurations. It is shown that the plasma potential distribution is almost not sensitive to changes of the electrode potential, but depends on the magnetic field distribution and the electrode placement.
Date: October 16, 2001
Creator: Raitses, Y.; Staack, D. & Fisch, N. J.
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 85, No. 41, Ed. 1 Tuesday, October 16, 2001 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 85, No. 41, Ed. 1 Tuesday, October 16, 2001

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: October 16, 2001
Creator: Johnson, Jennifer
Object Type: Newspaper
System: The Gateway to Oklahoma History