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1999 Small Agency Management Control Audit
Report of the Texas State Auditor's Office related to the identification and evaluation of management controls at seven small agencies, specifically controls that are most critical in supporting the accomplishment of legislative mandates.
Date:
March 1999
Creator:
Texas. Office of the State Auditor.
Object Type:
Report
System:
The Portal to Texas History
2D Numerical Simulation of the Resistive Reconnection Layer
In this paper we present a two-dimensional numerical simulation of a reconnection current layer in incompressible resistive magnetohydrodynamics with uniform resistivity in the limit of very large Lundquist numbers. We use realistic boundary conditions derived consistently from the outside magnetic field, and we also take into account the effect of the back pressure from flow into the separatrix region. We find that within a few Alfvén times the system reaches a steady state consistent with the Sweet-Parker model, even if the initial state is Petschek-like.
Date:
March 1, 1999
Creator:
Kulsrud, R. M. & Uzdensky, D. A.
Object Type:
Report
System:
The UNT Digital Library
Ab-initio based calculations of vacancy formation and clustering energies including lattice relaxation in Fe{sub 3}Al
Vacancy formation and clustering significantly affect structural properties of transition-metal aluminides. Ab-initio quantum mechanical total-energy calculations using a full-potential linear combination of muffin-tin orbitals (LMTO) technique provide a convenient method of studying relevant characteristics such as changes in density of states, and charge redistribution around defects. Augmented with Hellmann-Feymann forces, LMTO allows calculations of relaxation geometries and relaxation energies. The authors have performed such calculations for vacancies and antisite substitutional point defects in Fe{sub 3}Al with DO{sub 3} crystallographic structure. There are two limiting factors complicating calculations of defect formation energies directly from ab-initio calculations. The first is that a single defect, due to the lattice periodicity necessitated by the use of ab-initio total energy techniques, cannot be considered as an isolated defect, even in the maximum computable simulation cell. Unlike previous calculations, which did not find a dependency on the size of the simulation cell, the calculations have shown a significant difference in results for 32- and 16- atom cells. This difference provides information about vacancy clustering since it can be explained by a relatively small attractive interaction energy {approximately} 0.2 eV between two vacancies located in adjacent simulation cells and separated by the lattice constant distance (5.52 {angstrom}). …
Date:
March 1, 1999
Creator:
Muratov, L. S.; Cooper, B. R. & Wills, J. M.
Object Type:
Article
System:
The UNT Digital Library
An AC magnetohydrodynamic micropump: towards a true integrated microfluidic system
An AC Magnetohydrodynamic (MHD) micropump has been demonstrated in which the Lorentz force is used to propel an electrolytic solution along a microchannel etched in silicon. This micropump has no moving parts, produces a continuous (not pulsatile) flow, and is compatible with solutions containing biological specimens. micropump, using the Lorentz force as the pumping mechanism for biological analysis. The AC Magnetohydrodynamic (MHD) micropump investigated produces a continuous flow and allows for complex microchannel design.
Date:
March 1, 1999
Creator:
Lee, A. P.; Lemoff, A. V.; McConaghy, C. F. & Miles, R. R.
Object Type:
Article
System:
The UNT Digital Library
Accelerated Aging of Polymer Composite Bridge Materials
Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure.
Date:
March 1, 1999
Creator:
Rodriguez, J. G.; Blackwood, L. G.; Torres, L. L.; Carlson, N. M. & Yoder, T. S.
Object Type:
Article
System:
The UNT Digital Library
Accelerated Aging of Polymer Composite Bridge Materials
Accelerated aging research on samples of composite material and candidate ultraviolet (UV) protective coatings is determining the effects of six environmental factors on material durability. Candidate fastener materials are being evaluated to determine corrosion rates and crevice corrosion effects at load-bearing joints. This work supports field testing of a 30-ft long, 18-ft wide polymer matrix composite (PMC) bridge at the Idaho National Engineering and Environmental Laboratory (INEEL). Durability results and sensor data from tests with live loads provide information required for determining the cost/benefit measures to use in life-cycle planning, determining a maintenance strategy, establishing applicable inspection techniques, and establishing guidelines, standards, and acceptance criteria for PMC bridges for use in the transportation infrastructure.
Date:
March 1, 1999
Creator:
Carlson, Nancy Margaret; Blackwood, Larry Gene; Torres, Lucinda Laine; Rodriguez, Julio Gallardo & Yoder, Timothy Scott
Object Type:
Article
System:
The UNT Digital Library
Accident response -- X-ray to virtual environment
The Engineering Sciences and Applications (ESA) Division of Los Alamos National Laboratory (LANL) has been working to develop a process to extract topographical information from digital x-ray data for modeling in a Computer Aided Design (CAD) environment and translation into a virtual environment. The application for this process is the evolution of a field deployable tool for use by the Accident Response Group (ARG) at the Laboratory. The authors have used both CT Scan and radiography data in their process development. The data is translated into a format recognizable by Pro/ENGINEER{trademark} and then into a virtual environment that can be operated on by dVISE{trademark}. They have successfully taken both CT Scan and radiograph data of single components and created solid and virtual environment models for interrogation.
Date:
March 1, 1999
Creator:
Hefele, J.; Stupin, D.; Kelley, T.; Sheats, M. & Tsai, C.
Object Type:
Article
System:
The UNT Digital Library
An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model
Development of methods to spray form materials by precisely controlled deposition of droplets can result in new manufacturing processes which offer improved metallurgical performance and reduced production costs. These processes require a more detailed knowledge of the fluid mechanics, heat transfer and solidification that occur during droplet spreading. Previous work using computer simulations of this process have been difficult to implement and have required long running times. This paper examines the use of an alternative, simplified, method developed by Madjeski for solving for the problem of droplet spreading and solidification. These simplifications reduce the overall splat spreading and solidification problem to a closed-form differential equation. This differential equation is then solved under various conditions as reported from recent publications of experimental and numerical results of drop analysis. The results from the model are compared in terms of maximum spl at diameter, minimum splat thickness, and time for the droplet spreading to reach 95% of the maximum diameter. The results indicate that the accuracy of the model can be improved by accounting for energy losses in the initial rate of droplet spreading. The model results show that the predictions of experimental results are improved to within 30% over a wide range …
Date:
March 1, 1999
Creator:
Aceves, S. M.; Sahai, V. & Shapiro, A. B.
Object Type:
Article
System:
The UNT Digital Library
Acoustic detection of Immiscible Liquids in Sand
Laboratory cross-well P-wave transmission at 90 kHz was measured in a 61 cm diameter by 76 cm tall water-saturated sand pack, before and after introducing a non-aqueous phase organic liquid (NAPL) (n-dodecane). In one experiment NAPL was introduced to form a lens trapped by a low permeability layer; a second experiment considered NAPL residual trapped behind the front of flowing NAPL. The NAPL caused significant changes in the travel time and amplitude of first arrivals, as well as the generation of diffracted waves arriving after the direct wave. The spatial variations in NAPL saturation obtained from excavation at the end of the experiment correlated well with the observed variations in the P-wave amplitudes and travel times. NAPL residual saturation changes from NAPL flow channels of 3 to 4% were detectable and the 40 to 80% NAPL saturation in the NAPL lens was clearly visible at acoustic frequencies. The results of these experiments demonstrate that small NAPL saturations may be more easily detected with amplitude rather than travel time data, but that the relationships between the amplitude changes and NAPL saturation maybe more complex than those for velocity.
Date:
March 1, 1999
Creator:
Geller, Jil T.; Kowalsky, Michael B.; Seifert, Patricia K. & Nihei, Kurt T.
Object Type:
Article
System:
The UNT Digital Library
Advanced Light Source Activity Report 1997/1998
This Lawrence Berkeley National Laboratory, Advanced Light Source (ALS) activity report for 1997/98 discusses the following topics: Introduction and Overview; Science Highlights; Facility Report; Special Events; ALS Advisory Panels 1997/98; ALS Staff 1997/98 and Facts and Figures for the year.
Date:
March 1, 1999
Creator:
Greiner, Annette
Object Type:
Report
System:
The UNT Digital Library
Advances in crosswell electromagnetics steel cased boreholes
The Crosswell electromagnetic (EM) induction technique ideally measures the resistivity distribution between boreholes which may often be cased with carbon steel. Quantification of the effect of such steel casing on the induced field is the most significant limitation of the technique. Recent data acquired at a site in Richmond, California quantify the effect of steel casing on induction measurements and demonstrate this effect to be separable. This unique site contains adjacent steel and plastic wells in which frequency soundings demonstrate low spectrum (1.0 - 50 Hz) measurements an effective means of isolating the casing response from, the formation response. It is also shown that the steel casing effect on the induction coil is highly localized, and limited to less than 0.30 meters above and below the coil.
Date:
March 1, 1999
Creator:
Harben, P E; Kirkendall, B A & Lewis, J P
Object Type:
Article
System:
The UNT Digital Library
The Age, Volume 22, Number 3, March 1999
Monthly publication containing information related to Chambers County, Texas, including current events of the Chambers County Historical Commission, the Wallisville Heritage Park, and the Chambers County historical and genealogical societies; reprinted newspaper articles about county events and citizens; and historical news and records.
Date:
March 1999
Creator:
Wallisville Heritage Park (Organization)
Object Type:
Journal/Magazine/Newsletter
System:
The Portal to Texas History
AGS EXPERIMENTS- 1996, 1997, 1998, 1999 (FIFTEENTH EDITION)
None
Date:
March 1, 1999
Creator:
LO PRESTI,P.
Object Type:
Report
System:
The UNT Digital Library
AGS experiments -- 1996, 1997, 1998, 1999. Fifteenth edition
This report is a compilation of two-page summaries for AGS experiments for FY 1996, FY 1997, FY 1998, FY 1999. The bulk of the experiments are for high energy physics and nuclear physics programs. Also included are the run schedules for the AGS for each of those years and a listing of publications of AGS experiments for 1982--1999.
Date:
March 1, 1999
Creator:
Lo Presti, P.
Object Type:
Report
System:
The UNT Digital Library
Los Alamos National Laboratory Superconductivity Technology Center Annual Progress Report: 1997
Development of high-temperature superconductors (HTS) has undergone tremendous progress during the past year. Kilometer tape lengths and associated magnets based on BSCCO materials are now commercially available from several industrial partners. Superconducting properties in the exciting YBCO coated conductors continue to be improved over longer lengths. The Superconducting Partnership Initiative (SPI) projects to develop HTS fault current limiters and transmission cables have demonstrated that HTS prototype applications can be produced successfully with properties appropriate for commercial applications. Research and development activities at LANL related to the HTS program for Fiscal Year 1997 are collected in this report. LANL continues to support further development of Bi2223 and Bi2212 tapes in collaboration with American Superconductor Corporation (ASC) and Oxford Superconductivity Technology, Inc. (OSTI), respectively. The tape processing studies involving novel thermal treatments and microstructural characterization have assisted these companies in commercializing these materials. The research on second-generation YBCO-coated conductors produced by pulsed-laser deposition (PLD) over buffer template layers produced by ion beam-assisted deposition (IBAD) continues to lead the world. The applied physics studies of magnetic flux pinning by proton and heavy ion bombardment of BSCCO and YBCO tapes have provided many insights into improving the behavior of these materials in magnetic fields. …
Date:
March 1, 1999
Creator:
Willis, Jeffrey O.; Newnam, Brian E. & Peterson, Dean E.
Object Type:
Report
System:
The UNT Digital Library
ALCAR - A Model for Horizontal R&D Consortia
The ALCAR<sup>TM</sup> Consortium was created to develop a low cost, non-heat treatable automotive body sheet alloy. This paper will discuss the management aspects of organizing and running a horizontal consortium for competing companies to cooperate in conducting pre-competitive research and development involving the US Department of Energy, National Laboratories, Universities and industrial consultants.
Date:
March 1999
Creator:
Barthold, G. B.; Das, S. K. & Hayden, H. W.
Object Type:
Article
System:
The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 99, No. 300, Ed. 1 Monday, March 1, 1999
Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date:
March 1, 1999
Creator:
Cole, Carol
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 108, No. 60, Ed. 1 Monday, March 1, 1999
Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date:
March 1, 1999
Creator:
Schwind, Jim & Holton, Kathleen
Object Type:
Newspaper
System:
The Portal to Texas History
Analysis of accelerator based neutron spectra for BNCT using proton recoil spectroscopy
Boron Neutron Capture Therapy (BNCT) is a promising binary treatment modality for high-grade primary brain tumors (glioblastoma multiforme, GM) and other cancers. BNCT employs a boron-10 containing compound that preferentially accumulates in the cancer cells in the brain. Upon neutron capture by {sup 10}B energetic alpha particles and triton released at the absorption site kill the cancer cell. In order to gain penetration depth in the brain Fairchild proposed, for this purpose, the use of energetic epithermal neutrons at about 10 keV. Phase 1/2 clinical trials of BNCT for GM are underway at the Brookhaven Medical Research Reactor (BMRR) and at the MIT Reactor, using these nuclear reactors as the source for epithermal neutrons. In light of the limitations of new reactor installations, e.g. cost, safety and licensing, and limited capability for modulating the reactor based neutron beam energy spectra, alternative neutron sources are being contemplated for wider implementation of this modality in a hospital environment. For example, accelerator based neutron sources offer the possibility of tailoring the neutron beams, in terms of improved depth-dose distributions, to the individual and offer, with relative ease, the capability of modifying the neutron beam energy and port size. In previous work new concepts …
Date:
March 1, 1999
Creator:
Wielopolski, L.; Ludewig, H.; Powell, J.R.; Raparia, D.; Alessi, J.G. & Lowenstein, D.I.
Object Type:
Report
System:
The UNT Digital Library
Analysis of heat transfer during quenching of a gear blank
This paper presents experimental and numerical results for the quench of a gear blank in agitated and stagnant oil. Heat transfer within the gear blank is analyzed with a whole domain-optimizer technique inverse solution method, to calculate the time history at every point in the gear blank. The development of this procedure represents the first stage in an overall analysis of the quench process that will later include material phase transformations and deformation. The paper presents ten variations in setting up the inverse problem, to analyze which combination of independent variables and decision variables results in the best match between experimental and numerical results. The results indicate that dividing the boundary of the gear blank into four zones and assigning a fixed heat transfer coefficient or heat flux to each zone yields an average RMS error (average difference between experimental and numerical results) of the order of 40 K. This error can be reduced by either increasing the number of zones, by reducing the number of thermocouples being matched, or by allowing the heat transfer or heat flux to vary within the zones. Of these possibilities, variation of heat transfer within the zones gives the best improvement in the quality …
Date:
March 1, 1999
Creator:
Aceves, S M & Sahai, V
Object Type:
Article
System:
The UNT Digital Library
An analysis of the uncertainty in temperature and density estimates from fitting model spectra to data. 1998 summer research program for high school juniors at the University of Rochester`s Laboratory for Laser Energetics: Student research reports
Temperature and density histories of direct-drive laser fusion implosions are important to an understanding of the reaction`s progress. Such measurements also document phenomena such as preheating of the core and improper compression that can interfere with the thermonuclear reaction. Model x-ray spectra from the non-LTE (local thermodynamic equilibrium) radiation transport post-processor for LILAC have recently been fitted to OMEGA data. The spectrum fitting code reads in a grid of model spectra and uses an iterative weighted least-squares algorithm to perform a fit to experimental data, based on user-input parameter estimates. The purpose of this research was to upgrade the fitting code to compute formal uncertainties on fitted quantities, and to provide temperature and density estimates with error bars. A standard error-analysis process was modified to compute these formal uncertainties from information about the random measurement error in the data. Preliminary tests of the code indicate that the variances it returns are both reasonable and useful.
Date:
March 1, 1999
Creator:
Schubmehl, M.
Object Type:
Report
System:
The UNT Digital Library
Analyzing algorithms for nonlinear and spatially nonuniform phase shifts in the liquid crystal point diffraction interferometer. 1998 summer research program for high school juniors at the University of Rochester`s Laboratory for Laser Energetics: Student research reports
Phase-shifting interferometry has many advantages, and the phase shifting nature of the Liquid Crystal Point Diffraction Interferometer (LCPDI) promises to provide significant improvement over other current OMEGA wavefront sensors. However, while phase-shifting capabilities improve its accuracy as an interferometer, phase-shifting itself introduces errors. Phase-shifting algorithms are designed to eliminate certain types of phase-shift errors, and it is important to chose an algorithm that is best suited for use with the LCPDI. Using polarization microscopy, the authors have observed a correlation between LC alignment around the microsphere and fringe behavior. After designing a procedure to compare phase-shifting algorithms, they were able to predict the accuracy of two particular algorithms through computer modeling of device-specific phase shift-errors.
Date:
March 1, 1999
Creator:
Jain, N.
Object Type:
Report
System:
The UNT Digital Library
Anisotropic multi-resolution analysis in 2D, application to long-range correlations in cloud mm-radar fields
Because of Earth`s gravitational field, its atmosphere is strongly anisotropic with respect to the vertical; the effect of the Earth`s rotation on synoptic wind patterns also causes a more subtle form of anisotropy in the horizontal plane. The authors survey various approaches to statistically robust anisotropy from a wavelet perspective and present a new one adapted to strongly non-isotropic fields that are sampled on a rectangular grid with a large aspect ratio. This novel technique uses an anisotropic version of Multi-Resolution Analysis (MRA) in image analysis; the authors form a tensor product of the standard dyadic Haar basis, where the dividing ratio is {lambda}{sub z} = 2, and a nonstandard triadic counterpart, where the dividing ratio is {lambda}{sub x} = 3. The natural support of the field is therefore 2{sup n} pixels (vertically) by 3{sup n} pixels (horizontally) where n is the number of levels in the MRA. The natural triadic basis includes the French top-hat wavelet which resonates with bumps in the field whereas the Haar wavelet responds to ramps or steps. The complete 2D basis has one scaling function and five wavelets. The resulting anisotropic MRA is designed for application to the liquid water content (LWC) field in …
Date:
March 1, 1999
Creator:
Davis, Anthony B. & Clothiaux, Eugene
Object Type:
Article
System:
The UNT Digital Library
Annual Meeting of the Texas Society, Sons of the American Revolution, 1999
Program for the 104th annual meeting of the Texas Society Sons of the American Revolution, held from March 12 through the 14, 1999 at the Sheraton North Houston Hotel, in Houston, Texas, including a list of sessions for the meeting and related information about the organization and conference. The meeting was called to order by President Robert W. Coker, in the Ampitheater of the Sheraton North Houston Hotel.
Date:
March 1999
Creator:
Sons of the American Revolution. Texas Society.
Object Type:
Pamphlet
System:
The UNT Digital Library