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1999 Gordon Research Conference on Microbial Population Biology. Final Progress Report (open access)

1999 Gordon Research Conference on Microbial Population Biology. Final Progress Report

None
Date: July 23, 1999
Creator: unknown
Object Type: Article
System: The UNT Digital Library
29th Annual PolyMAC Meeting: Book of Abstracts (open access)

29th Annual PolyMAC Meeting: Book of Abstracts

A sixteen-run, Resolution IV, fractional factorial screening design has been used to evaluate the relative significance of seven independent material and process variables for an electrically deposited commercial acrylic paint. A Resolution IV design was chosen so that variable interactions could be detected without any interference from the effects of the variables themselves. Because resource limitations did not permit use of a Resolution V design, the two-way interactions were confounded with one another in groups of three, which unfortunately made interpretation of the results more complicated. Each design point was replicated once and a pair of centerpoints were run at the beginning, in the middle and at the end of the design points. A total of 38 test panels were prepared. Independent variables used in this experiment were total charge, current density, mixer speed, silica content, crossover point, temperature and solids fraction. The magnitude of each independent variable's effect on the dependent response variables was estimated by fitting a first-order model with two-way interaction terms. Three-way interactions were assumed to be insignificant. Interaction confounding was eliminated by using the significance of the independent variables to determine which of the three possible interactions was significant. Data analysis was performed using the …
Date: July 23, 1999
Creator: Balazs, B.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 107, Ed. 1 Friday, July 23, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 107, Ed. 1 Friday, July 23, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 1999
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site (open access)

Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site

We have previously presented simple elastic deformation modeling results for three classes of seismic events of concern in monitoring the CTBT--underground explosions, mine collapses and earthquakes. Those results explored the theoretical detectability of each event type using synthetic aperture radar interferometry (InSAR) based on commercially available satellite data. In those studies we identified and compared the characteristics of synthetic interferograms that distinguish each event type, as well the ability of the interferograms to constrain source parameters. These idealized modeling results, together with preliminary analysis of InSAR data for the 1995 mb 5.2 Solvay mine collapse in southwestern Wyoming, suggested that InSAR data used in conjunction with regional seismic monitoring holds great potential for CTBT discrimination and seismic source analysis, as well as providing accurate ground truth parameters for regional calibration events. In this paper we further examine the detectability and ''discriminating'' power of InSAR by presenting results from InSAR data processing, analysis and modeling of the surface deformation signals associated with underground explosions. Specifically, we present results of a detailed study of coseismic and postseismic surface deformation signals associated with underground nuclear and chemical explosion tests at the Nevada Test Site (NTS). Several interferograms were formed from raw ERS-1/2 radar …
Date: July 23, 1999
Creator: Foxall, W; Vincent, P & Walter, W
Object Type: Article
System: The UNT Digital Library
Analysis of the Interaction of Short-Pulse High-Fluence Radiation with Targets (open access)

Analysis of the Interaction of Short-Pulse High-Fluence Radiation with Targets

We generally use large-scale hydrocodes to study the dynamic response of targets to influence pulsed radiation loads. However, for many applications where the desired solution does not require a detailed specification of pressure- or velocity-time histories, there are simple analytic approaches that can yield surprisingly accurate results. Examples include determining either the final velocity of a radiation-driven flying plate or the impulse delivered to a structural element. These methods are all based on relatively straightforward use of conservation of mass and momentum, but they typically need one scaling-law parameter. In this context, short pulse means short compared to the characteristic time of the desired response, which allows for the phenomena to be essentially uncoupled. High fluence means that the input energy is great enough to yield vaporization or blowoff of one or more portions of the configuration. We discuss some of these methods, give examples, and suggest limitations and criteria for their use.
Date: July 23, 1999
Creator: Lawrence, R.Jeffery
Object Type: Article
System: The UNT Digital Library
[Application Title: N T Educators on the Visual Arts] (open access)

[Application Title: N T Educators on the Visual Arts]

An application filled out by North Texas Institute for Educators on the Visual Arts to apply for a Texas Commission on the Arts grant. The following pages are filled out with sensitive information on the North Texas Institute for Educators on the Visual Arts organization as they request support for the period of September 1, 1999 to August 1, 2000.
Date: July 23, 1999
Creator: North Texas Institute for Educators on the Visual Arts
Object Type: Text
System: The UNT Digital Library
Appropriations for FY2000: Treasury, Postal Service, Executive Office of the President, and General Government (open access)

Appropriations for FY2000: Treasury, Postal Service, Executive Office of the President, and General Government

This report discusses Treasury, Postal Service, Executive Office of the President, and General Government Appropriations for FY2000.
Date: July 23, 1999
Creator: Gressle, Sharon
Object Type: Report
System: The UNT Digital Library
The Ascension Island hydroacoustic experiment: purpose, data set features and plans for future analysis (open access)

The Ascension Island hydroacoustic experiment: purpose, data set features and plans for future analysis

Calibration of hydroacoustic and T-phase stations for Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring will be an important element in establishing new operational stations and upgrading existing stations. Calibration of hydroacoustic stations is herein defined as precision location of the hydrophones and determination of the amplitude response from a known source energy. T-phase station calibration is herein defined as a determination of station site attenuation as a function of frequency, bearing, and distance for known impulsive energy sources in the ocean. To understand how to best conduct calibration experiments for both hydroacoustic and T-phase stations, an experiment was conducted in May, 1999 at Ascension Island in the South Atlantic Ocean. The experiment made use of a British oceanographic research vessel and collected data that will be used for CTBT issues and for fundamental understanding of the Ascension Island volcanic edifice.
Date: July 23, 1999
Creator: Harben, P E; Rock, D & Rodgers, A J
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 228, Ed. 1 Friday, July 23, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 228, Ed. 1 Friday, July 23, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 23, 1999
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
Behavior model for performance assessment. (open access)

Behavior model for performance assessment.

Every individual channels information differently based on their preference of the sensory modality or representational system (visual auditory or kinesthetic) we tend to favor most (our primary representational system (PRS)). Therefore, some of us access and store our information primarily visually first, some auditorily, and others kinesthetically (through feel and touch); which in turn establishes our information processing patterns and strategies and external to internal (and subsequently vice versa) experiential language representation. Because of the different ways we channel our information, each of us will respond differently to a task--the way we gather and process the external information (input), our response time (process), and the outcome (behavior). Traditional human models of decision making and response time focus on perception, cognitive and motor systems stimulated and influenced by the three sensory modalities, visual, auditory and kinesthetic. For us, these are the building blocks to knowing how someone is thinking. Being aware of what is taking place and how to ask questions is essential in assessing performance toward reducing human errors. Existing models give predications based on time values or response times for a particular event, and may be summed and averaged for a generalization of behavior(s). However, by our not establishing …
Date: July 23, 1999
Creator: Borwn-VanHoozer, S. A.
Object Type: Article
System: The UNT Digital Library
The Boerne Star (Boerne, Tex.), Vol. 94, No. 59, Ed. 1 Friday, July 23, 1999 (open access)

The Boerne Star (Boerne, Tex.), Vol. 94, No. 59, Ed. 1 Friday, July 23, 1999

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: July 23, 1999
Creator: Keasling, Edna & Fierro, Jennifer
Object Type: Newspaper
System: The Portal to Texas History
Calibration of seismic wave propagation in Jordan (open access)

Calibration of seismic wave propagation in Jordan

The Natural Resources Authority of Jordan (NRA), the USGS and LLNL have a collaborative project to improve the calibration of seismic propagation in Jordan and surrounding regions. This project serves common goals of CTBT calibration and earthquake hazard assessment in the region. These objectives include accurate location of local and regional earthquakes, calibration of magnitude scales, and the development of local and regional propagation models. In the CTBT context, better propagation models and more accurately located events in the Dead Sea rift region can serve as (potentially GT5) calibration events for generating IMS location corrections. The detection and collection of mining explosions underpins discrimination research. The principal activity of this project is the deployment of two broadband stations at Hittiyah (south Jordan) and Ruweishid (east Jordan). These stations provide additional paths in the region to constrain structure with surface wave and body wave tomography. The Ruweishid station is favorably placed to provide constraints on Arabian platform structure. Waveform modeling with long-period observations of larger earthquakes will provide constraints on 1-D velocity models of the crust and upper mantle. Data from these stations combined with phase observations from the 26 short-period stations of the Jordan National Seismic Network (JNSN) may allow …
Date: July 23, 1999
Creator: Al-Husien, A.; Amrat, A.; Harris, D.; Mayeda, K.; Nakanishi, K.; Rodgers, A. et al.
Object Type: Article
System: The UNT Digital Library
Calibration of seismic wave propagation in Kuwait (open access)

Calibration of seismic wave propagation in Kuwait

The Kuwait Institute of Scientific Research (KISR), the USGS and LLNL are collaborating to calibrate seismic wave propagation in Kuwait and surrounding regions of the northwest Arabian Gulf using data from the Kuwait National Seismic Network (KNSN). Our goals are to develop local and regional propagation models for locating and characterizing seismic events in Kuwait and portions of the Zagros mountains close to Kuwait. The KNSN consists of 7 short-period stations and one broadband (STS-2) station. Constraints on the local velocity structure may be derived from joint inversions for hypocenters of local events and the local velocity model, receiver functions from three-component observations of teleseisms, and surface wave phase velocity estimated from differential dispersion measurements made across the network aperture. Data are being collected to calibrate travel-time curves for the principal regional phases for events in the Zagros mountains. The available event observations span the distance range from approximately 2.5 degrees to almost 9 degrees. Additional constraints on structure across the deep sediments of the Arabian Gulf will be obtained from long-period waveform modeling.
Date: July 23, 1999
Creator: Al-Awadhi, J.; Endo, E.; Fryall, F.; Harris, D.; Mayeda, K.; Rodgers, A. et al.
Object Type: Article
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 104, No. 59, Ed. 1 Friday, July 23, 1999 (open access)

The Clifton Record (Clifton, Tex.), Vol. 104, No. 59, Ed. 1 Friday, July 23, 1999

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: July 23, 1999
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
Complete regional waveform modeling to estimate seismic velocity structure and source parameters for CTBT monitoring (open access)

Complete regional waveform modeling to estimate seismic velocity structure and source parameters for CTBT monitoring

The velocity structures and source parameters estimated by waveform modeling provide valuable information for CTBT monitoring. The inferred crustal and uppermost mantle structures advance understanding of tectonics and guides regionalization for event location and identification efforts. Estimation of source parameters such as seismic moment, depth and mechanism (whether earthquake, explosion or collapse) is crucial to event identification. In this paper we briefly outline some of the waveform modeling research for CTBT monitoring performed in the last year. In the future we will estimate structure for new regions by modeling waveforms of large well-observed events along additional paths. Of particular interest will be the estimation of velocity structure in aseismic regions such as most of Africa and the Former Soviet Union. Our previous work on aseismic regions in the Middle East, north Africa and south Asia give us confidence to proceed with our current methods. Using the inferred velocity models we plan to estimate source parameters for smaller events. It is especially important to obtain seismic moments of earthquakes for use in applying the Magnitude-Distance Amplitude Correction (MDAC; Taylor et al., 1999) to regional body-wave amplitudes for discrimination and calibrating the coda-based magnitude scales.
Date: July 23, 1999
Creator: Bredbeck, T.; Rodgers, A. & Walter, W.
Object Type: Article
System: The UNT Digital Library
Critical current densities in Bi-2223 sinter forgings. (open access)

Critical current densities in Bi-2223 sinter forgings.

(Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (Bi-2223) bars, prepared by sinter forging, exhibited good phase purity and strong textures with the c axes of the Bi-2223 grains parallel to the forging direction. The initial zero-field critical current density (J{sub c}) of the bars was 10{sup 3} A/cm{sup 2}, but because the forged bars were uncoated, this value decreased with repeated thermal cycling. J{sub c} as a function of applied magnetic field magnitude and direction roughly followed the dependencies exhibited by Ag-sheathed Bi-2223 tapes, but the forged bars were more strongly dependent on field strength and less strongly dependent on field angle.
Date: July 23, 1999
Creator: Balachandran, U.; Fisher, B. L.; Goretta, K. C.; Harris, N. C. & Murayama, N.
Object Type: Article
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 16, No. 12, Ed. 1 Friday, July 23, 1999 (open access)

Dallas Voice (Dallas, Tex.), Vol. 16, No. 12, Ed. 1 Friday, July 23, 1999

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: July 23, 1999
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
Decontamination and decommissioning activities photobriefing book FY 1998. (open access)

Decontamination and decommissioning activities photobriefing book FY 1998.

Fiscal Year (FY) 1998 was very successful in terms of Decontamination and Decommissioning (D&D) project completions. This photobriefing book highlights these projects and activities in one ongoing project. Brief descriptions of projects planned for the future are also provided. Two D&D projects funded by the US DOE Office of Environmental Management (EM-40) were completed safely and on schedule in FY 1998: (1) Argonne Thermal Source Reactor (ATSR) was a low-power research reactor that operated from 1950 to 1989; and (2) The Building 594 (a.k.a. 579) Waste Ion-Exchange Facility was an obsolete facility constructed in the 1950s to process waste fluids from a collecting lagoon. Field work at one project was ongoing during FY 1998: (1) Chicago Pile 5 (CP-5) was a 5-megawatt, heavy water-moderated, enriched uranium-fueled reactor used to produce neutrons for scientific research from 1954-79. The reactor was shut down and defueled in 1979. D&D is scheduled to be completed in FY 2000. Project experience has lent itself to developing unique staff capabilities. The D&D group was chosen as lead organization for a project supported with operating funds provided by Argonne's Plant Facilities and Services (PFS) Division. This project was also completed safely and on schedule in FY 1998: …
Date: July 23, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Depth and source mechanism estimation for special event analysis, event screening, and regional calibration (open access)

Depth and source mechanism estimation for special event analysis, event screening, and regional calibration

We have summarized the advantages and disadvantages of a variety of techniques for depth and mechanism estimation and suggest that significant work remains to be done for events with magnitudes of interest for test ban monitoring. We also describe a new, waveform modeling-based tool for fast and accurate, high-resolution depth and mechanism estimation. Significant features of this tool include its speed and accuracy and its applicability at relatively high frequencies. These features allow a user to rapidly determine accurate, high-resolution depth estimates and constraints on source mechanism for relatively small magnitude (mb-4.5) events. Based on the accuracy of depth estimates obtained with this tool, we conclude it is useful for both the analysis of unusual or suspect events and for event screening. We also find that this tool provides significant constraints on source mechanism and have used it to develop ''ground-truth'' estimates of depth and mechanism for a set of events in the Middle East and North Africa. These ''ground-truth'' depths and mechanisms should be useful for regional calibration.
Date: July 23, 1999
Creator: Goldstein, P.; Dodge, D.; Ichinose, Rodgers, A.; Bhattacharyya, B. & Leach, R.
Object Type: Article
System: The UNT Digital Library
Developments in Synchrotron X-Ray Computed Microtomography at the National Synchrotron Light Source. (open access)

Developments in Synchrotron X-Ray Computed Microtomography at the National Synchrotron Light Source.

Last year, the X27A beamline at the National Synchrotron Light Source (NSLS) became dedicated solely to X-Ray Computed Microtomography (XCMT). This is a third-generation instrument capable of producing tomographic volumes of 1-2 micron resolution over a 2-3mm field of view. Recent enhancements will be discussed. These have focused on two issues: the desire for real-time data acquisition and processing and the need for highly monochromatic beam (.1 % energy bandpass). The latter will permit k-edge subtraction studies and will provide improved image contrast from below the Cr (6 keV) up to the Cs (36 keV) k-edge. A range of applications that benefit from these improvements will be discussed as well. These two goals are somewhat counterproductive, however; higher monochromaticity yields a lower flux forcing longer data acquisition times. To balance the two, a more efficient scintillator for X-ray conversion is being developed. Some testing of a prototype scintillator has been performed; preliminary results will be presented here. In the meantime, data reconstruction times have been reduced, and the entire tomographic acquisition, reconstruction and volume rendering process streamlined to make efficient use of synchrotron beam time. A Fast Filtered Back Transform (FFBT) reconstruction program recently developed helped to reduce the time …
Date: July 23, 1999
Creator: Dowd, B. A.
Object Type: Article
System: The UNT Digital Library
DOE Security: Protecting Nuclear Material and Information (open access)

DOE Security: Protecting Nuclear Material and Information

Congress is focusing on problems with security at the Department of Energy’s (DOE) national security facilities, especially the nuclear weapon laboratories. Problems include espionage from within the labs and protection of nuclear material and facilities from outside attack. This report describes the main components of DOE’s security system and reviews current efforts to address shortcomings.
Date: July 23, 1999
Creator: Davis, Zachary S.
Object Type: Report
System: The UNT Digital Library
Electronic Sputtering of Solids by Slow, Highly Charged Ions: Fundamentals and Applications (open access)

Electronic Sputtering of Solids by Slow, Highly Charged Ions: Fundamentals and Applications

Characterization tools have been developed to study the performance characteristics and reliability of surface micromachined actuators. These tools include (1) the ability to electrically stimulate or stress the actuator, (2) the capability to visually inspect the devices in operation, (3) a method for capturing operational information, and (4) a method to extract performance characteristics from the operational information. Additionally, a novel test structure has been developed to measure electrostatic forces developed by a comb drive actuator.
Date: July 23, 1999
Creator: Banks, J. C.; Barnes, A. V.; Doyle, B. L.; Hamza, A. V.; Machicoane, G. A.; McDonald, J. W. et al.
Object Type: Article
System: The UNT Digital Library
End-to-End Radiographic Systems Simulation (open access)

End-to-End Radiographic Systems Simulation

This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to develop a validated end-to-end radiographic model that could be applied to both x-rays and protons. The specific objectives were to link hydrodynamic, transport, and magneto-hydrodynamic simulation software for purposes of modeling radiographic systems. In addition, optimization and analysis algorithms were to be developed to validate physical models and optimize the design of radiographic facilities.
Date: July 23, 1999
Creator: Mathews, A.; Kwan, T.; Buescher, K.; Snell, C. & Adams, K.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, July 23, 1999 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, July 23, 1999

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 1999
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History