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12th International Mouse Genome Conference (open access)

12th International Mouse Genome Conference

None
Date: October 1, 1998
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1997 Annual Site Environmental Report (ASER) (open access)

1997 Annual Site Environmental Report (ASER)

The SLAC program centers around experimental and theoretical research in elementary particle physics using accelerated electron beams and a broad program of research in atoms and solid-state physics, chemistry, and biology using synchrotron radiation from accelerated electron beams. There is also an active program in the development of accelerators, detectors, and new sources and instrumentation for synchrotron radiation research. The main instrument of research is the 3.2-km linear accelerator (linac) that generates high intensity beams of electrons and positrons up to 50 GeV, which are among the highest energy electron and positron beams available in the world. The linac is also used for injecting electrons and positrons into colliding-beam storage rings for particle physics research. The Positron-Electron Project (PEP) storage ring is about 800 meters in diameter. The PEP program was completed several years ago. PEP is now being upgraded to serve as an Asymmetric B Factory (or PEP-II) that will study the B meson. PEP-II will make use of much of PEP's existing equipment and infrastructure, and is scheduled for completion in 1998. A smaller storage ring, the Stanford Positron-Electron Asymmetric Ring (SPEAR) has its own smaller linac and a booster ring for injecting accelerated beams of electrons. SPEAR …
Date: October 1, 1998
Creator: Holden, Gene
Object Type: Report
System: The UNT Digital Library
1998 federal technical standards workshop: Proceedings (open access)

1998 federal technical standards workshop: Proceedings

The theme for the 1998 workshop was Standards Management -- A World of Change and Opportunities. The workshop`s goal was to further the implementation of the National Technology Transfer and Advancement Act of 1995 (Public Law 104-113) through the sharing of standards management success stories, lessons learned, and emerging initiatives within the Executive Branch of the Federal Government. The target audience for this workshop included agency/department and contractor personnel and representatives of standards developing organizations that either used technical standards in their work for the Federal Government of participated in standards writing/management activities in support of the missions and programs of Federal agencies/departments. As with previous standards workshops sponsored by the DOE, views on the technical subject areas under the workshop theme were solicited from and provided by agency Standards Executives and standards program managers, voluntary standards organizations, and the private sector. This report includes vugraphs of the presentations.
Date: October 1998
Creator: unknown
Object Type: Article
System: The UNT Digital Library
3D Simulations of line emission from ICF capsules (open access)

3D Simulations of line emission from ICF capsules

Line emission from ICF implosions can be used to diagnose the temperature of the DT fuel and provides an indication of the distortion in the fuel-pusher interface. 2D simulations have provided valuable insights into the usefulness of argon and titanium dopants as diagnostics of instabilities. Characterizing the effects of drive asymmetries requires 3D modeling with large demands for computer time and memory, necessitating the use of parallel computers. We present the results of some 3D simulations achieved with a code utilizing both shared memory and distributed parallelism. We discuss the code structure and related performance issues.
Date: October 1, 1998
Creator: Langer, S.; Marinak, M. M. & Scott, H.
Object Type: Article
System: The UNT Digital Library
7th International Meshing Roundtable '98 (open access)

7th International Meshing Roundtable '98

The goal of the 7th International Meshing Roundtable is to bring together researchers and developers from industry, academia, and government labs in a stimulating, open environment for the exchange of technical information related to the meshing process. In the past, the Roundtable has enjoyed significant participation from each of these groups from a wide variety of countries.
Date: October 1, 1998
Creator: Eldred, T.J.
Object Type: Article
System: The UNT Digital Library
Accurate, finite-volume methods for 3D MHD on unstructured Lagrangian meshes (open access)

Accurate, finite-volume methods for 3D MHD on unstructured Lagrangian meshes

Previous 2D methods for magnetohydrodynamics (MHD) have contributed both to development of core code capability and to physics applications relevant to AGEX pulsed-power experiments. This strategy is being extended to 3D by development of a modular extension of an ASCI code. Extension to 3D not only increases complexity by problem size, but also introduces new physics, such as magnetic helicity transport. The authors have developed a method which incorporates all known conservation properties into the difference scheme on a Lagrangian unstructured mesh. Because the method does not depend on the mesh structure, mesh refinement is possible during a calculation to prevent the well known problem of mesh tangling. Arbitrary polyhedral cells are decomposed into tetrahedrons. The action of the magnetic vector potential, A {center_dot} {delta}l, is centered on the edges of this extended mesh. For ideal flow, this maintains {del} {center_dot} B = 0 to round-off error. Vertex forces are derived by the variation of magnetic energy with respect to vertex positions, F = {minus}{partial_derivative}W{sub B}/{partial_derivative}r. This assures symmetry as well as magnetic flux, momentum, and energy conservation. The method is local so that parallelization by domain decomposition is natural for large meshes. In addition, a simple, ideal-gas, finite pressure …
Date: October 1, 1998
Creator: Barnes, D. C. & Rousculp, C. L.
Object Type: Article
System: The UNT Digital Library
Active and passive computed tomography algorithm with a constrained conjugate gradient solution (open access)

Active and passive computed tomography algorithm with a constrained conjugate gradient solution

An active and passive computed tomographic technique (A&PCT) has been developed at the Lawrence Livermore National Laboratory (LLNL). The technique uses an external radioactive source and active tomography to map the attenuation within a waste drum as a function of mono-energetic gamma-ray energy. Passive tomography is used to localize and identify specific radioactive waste within the same container. The passive data is corrected for attenuation using the active data and this yields a quantitative assay of drum activity. A&PCT involves the development of a detailed system model that combines the data from the active scans with the geometry of the imaging system. Using the system model, iterative optimization techniques are used to reconstruct the image from the passive data. Requirements for high throughput yield measured emission levels in waste barrels that are too low to apply optimization techniques involving the usual Gaussian statistics. In this situation a Poisson distribution, typically used for cases with low counting statistics, is used to create an effective maximum likelihood estimation function. An optimization algorithm, Constrained Conjugate Gradient (CCG), is used to determine a solution for A&PCT quantitative assay. CCG, which was developed at LLNL, has proven to be an efficient and effective optimization method …
Date: October 1, 1998
Creator: Goodman, D.; Jackson, J. A.; Martz, H. E. & Roberson, G. P.
Object Type: Article
System: The UNT Digital Library
Advanced composites technology (open access)

Advanced composites technology

The development of fiber composite components in next-generation munitions, such as sabots for kinetic energy penetrators and lightweight cases for advanced artillery projectiles, relies on design trade-off studies using validated computer code simulations. We are developing capabilities to determine the failure of advanced fiber composites under multiaxial stresses to critically evaluate three-dimensional failure models and develop new ones if necessary. The effects of superimposed hydrostatic pressure on failure of composites are being investigated using a high-pressure testing system that incorporates several unique features. Several improvements were made to the system this year, and we report on the first tests of both isotropic and fiber composite materials. The preliminary results indicate that pressure has little effect on longitudinal compression strength of unidirectional composites, but issues with obtaining reliable failures in these materials still remain to be resolved. The transverse compression strength was found to be significantly enhanced by pressure, and the trends observed for this property and the longitudinal strength are in agreement with recent models for failure of fiber composites.
Date: October 1, 1998
Creator: DeTeresa, S J; Groves, S E & Sanchez, R J
Object Type: Report
System: The UNT Digital Library
ADVANCED EMISSIONS CONTROL DEVELOPMENT PROGRAM (open access)

ADVANCED EMISSIONS CONTROL DEVELOPMENT PROGRAM

The objective of this project is to develop practical strategies and systems for the simultaneous control of SO{sub 2}, NO{sub x}, particulate matter, and air toxics emissions from coal-fired boilers in such a way as to keep coal economically and environmentally competitive as a utility boiler fuel. Of particular interest is the control of air toxics emissions through the cost-effective use of conventional flue gas clean-up equipment such as electrostatic precipitators (ESP's), fabric filters (baghouses), and SO{sub 2} removal systems such as wet scrubbers and various clean coal technologies. This objective will be achieved through extensive development testing in the state-of-the art, 10 MW{sub e} equivalent, Clean Environment Development Facility (CEDF). The project has extended the capabilities of the CEDF to facilitate air toxics emissions control development work on backend flue gas cleanup equipment. Specifically, an ESP, a baghouse, and a wet scrubber for SO{sub 2} (and air toxics) control were added--all designed to yield air toxics emissions data under controlled conditions, and with proven predictability to commercial systems. A schematic of the CEDF and the project test equipment is shown in Figure 1. The specific objectives of the project are to: (1) Measure and understand production and partitioning of …
Date: October 1, 1998
Creator: Holmes, M.J.
Object Type: Report
System: The UNT Digital Library
Advanced Recovery and Integrated Extraction System (ARIES) Fiscal Year 1996 Annual Report (open access)

Advanced Recovery and Integrated Extraction System (ARIES) Fiscal Year 1996 Annual Report

President Clinton issued Nonprolferation and Export Control Policy in September 1993 in response to the growing threat of nuclear proliferation. Four months later, in January 1994, President Clinton and Russia's President Yeltsin issued a Joint Statement Between the United States and Russia on Nonprollfieration of Weapons of Mass Destruction and the Means of Their Delivery. President Clinton announced on 1 March 1995, that approximately 200 metric tons of US- origin weapons-usable fissile materials had been declared surplus to US defense needs. The Advanced Recovery and Integrated Extraction System (ARIES) Demonstration Project is one part of the scientific response to President Clinton's promise to reduce the nuclear weapons stockpile. The work accomplished on the ARIES Demonstration Project during fiscal year 1996, 10ctober 1995 through 30 September 1996, is described in this report. The Department of Energy (DOE), by forming the Office of Fissile Materials Disposition (OFMD), has initiated a Fissile Materials Disposition Program. The first step is the disassembly and conversion of weapons pits. Of the 200 metric tons of US surplus fissile material, approximately 50 tons are weapons plutonium, and of these 50 tons, 2/3 is contained in pits. Weapons plutonium wili be extracted from pits, rendered to an unclassified …
Date: October 1, 1998
Creator: Dennison, David; Massey, Pamela W. & Nelson, Timothy O.
Object Type: Report
System: The UNT Digital Library
ADVANCED SAMPLING AND ANALYSIS OF FINE PARTICULATES. Final Topical Report which includes semiannual for the period of January 1, 1998 - June 30, 1998 (open access)

ADVANCED SAMPLING AND ANALYSIS OF FINE PARTICULATES. Final Topical Report which includes semiannual for the period of January 1, 1998 - June 30, 1998

Sampling tests indicated that the polycarbonate filters were marginally acceptable for in-stack fine-particle collection because of their 230 F melting point as well as requiring carbon coating to reduce charging effects. Vitreous carbon substrates, although not porous, have acceptable thermal stability as well as acceptable levels of charging. A porous silver membrane filter is also being considered for future testing. Pure reference samples of secondary aerosols have been successfully been collected on vitreous carbon substrates with good dispersion and found suitable for direct examination by scanning electron microscope (SEM) without prior coating or preparation. These samples will be used to develop optimum SEM measurement and quantification techniques related to the analysis of fine secondary aerosols.
Date: October 1, 1998
Creator: McCollor, Donald P.; Eylands, Kurt E. & Kleven, Patricia L.
Object Type: Report
System: The UNT Digital Library
Advances in PSII Deposited Diamond-Like Carbon Coatings for Use as a Barrier to Corrosion (open access)

Advances in PSII Deposited Diamond-Like Carbon Coatings for Use as a Barrier to Corrosion

Plasma source ion implantation (PSII) is a non line of sight process for implanting complex shaped targets without the need for complex fixturing. The breakdown initiation of materials coated with diamond-like carbon (DLC) produced by PSII occurs at defects in the DLC which expose the underlying material. To summarize these findings, a galvanic couple is established between the coating and exposed material at the base of the defect. Pitting and oxidation of the base and metal leads to the development of mechanical stress in the coating and eventually spallation of the coating. This paper presents our current progress in attempting to mitigate the breakdown of these coatings by implanting the parent material prior to coating with DLC. Ideally one would like to implant the parent material with chromium or molybdenum which are known to improve corrosion resistance, however, the necessary organometallics needed to implant these materials with PSII are not yet available. Here we report on the effects of carbon, nitrogen, and boron implantation on the susceptibility of PSII-DLC coated mild steel to breakdown.
Date: October 1, 1998
Creator: Lillard, R. S.; Butt, D. P.; Baker, N. P.; Walter, K. C. & Nastasi, M.
Object Type: Article
System: The UNT Digital Library
The Age, Volume 21, Number 10, October 1998 (open access)

The Age, Volume 21, Number 10, October 1998

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: October 1998
Creator: Wallisville Heritage Park (Organization)
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
The Albany News (Albany, Tex.), Vol. 123, No. 18, Ed. 1 Thursday, October 1, 1998 (open access)

The Albany News (Albany, Tex.), Vol. 123, No. 18, Ed. 1 Thursday, October 1, 1998

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: October 1, 1998
Creator: Lucas, Donnie A.
Object Type: Newspaper
System: The Portal to Texas History
ALE advantage in hypervelocity impact calculations (open access)

ALE advantage in hypervelocity impact calculations

The ALE3D code is used to model experiments relevant to hypervelocity impact lethality, carried out in the 4-5 km/s velocity range. The code is run in the Eulerian and ALE modes. Zoning in the calculations is refined beyond the level found in most lethality calculations, but still short of convergence. The level of zoning refinement that produces equivalent results in uniformly zoned Eulerian calculations and ALE ones utilizing specialized zoning, weighting and relaxation techniques is established. It takes 11 times fewer zones and about 60% as many cycles when ALE capabilities are used. Calculations are compared to experimental results.
Date: October 1, 1998
Creator: Gerassimenko, M. & Rathkopf, J.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 99, No. 171, Ed. 1 Thursday, October 1, 1998 (open access)

Altus Times (Altus, Okla.), Vol. 99, No. 171, Ed. 1 Thursday, October 1, 1998

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 1, 1998
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analysis of Multistage and Other Creep Data for Domal Salts (open access)

Analysis of Multistage and Other Creep Data for Domal Salts

There have existed for some time relatively sparse creep databases for a number of domal salts. Although all of these data were analyzed at the time they were reported, to date there has not been a comprehensive, overall evaluation within the same analysis framework. Such an evaluation may prove of value. The analysis methodology is based on the Multimechanism Deformation (M-D) description of salt creep and the corresponding model parameters determined from conventional creep tests. The constitutive model of creep wss formulated through application of principles involved in micromechanical modeling. It was possible, at minimum, to obtain the steady state parameters of the creep model from the data on the domal salts. When this was done, the creep of the domal salts, as compared to the well-defined Waste Isolation Pilot Plant (WIPP) bedded clean salt, was either essentially identical to, or significantly harder (more creep resistant) than WIPP salt. Interestingly, the domal salts form two distinct groups, either sofl or hard, where the difference is roughly a factor often in creep rate between the twcl groups. As might be expected, this classification corresponds quite well to the differences in magnitude of effective creep volume losses of the Strategic Petroleum Reserve …
Date: October 1, 1998
Creator: Munson, Darrell E.
Object Type: Report
System: The UNT Digital Library
ARAC simulations of the ash plume from the December 1997 eruption of Soufriere Hills Volcano, Montserrat (open access)

ARAC simulations of the ash plume from the December 1997 eruption of Soufriere Hills Volcano, Montserrat

Ash clouds generated by erupting volcanoes represent a serious hazard to military and civil aviation. The dispersion modeling system of the Atmospheric Release Advisory Capability (ARAC) has been used to model the cloud resulting from the eruption of the Soufriere Hills volcano, Montserrat in December 1997. A clone of parts of the ARAC system, now being installed at the Air Force Weather Agency (AFWA), will enable AFWA to provide hazard guidance to military operations in the vicinity of erupting volcanoes. This paper presents ARAC� s modeling results and discusses potential application of similar calculations for AFWA support during future events.
Date: October 1, 1998
Creator: Ellis, J. S.; Lefevre, R. J.; Pace, J. C.; Vogt, P. J. & Voight, B.
Object Type: Article
System: The UNT Digital Library
ARAC's operational support of the Cassini Launch (open access)

ARAC's operational support of the Cassini Launch

The Atmospheric Release Advisory Capability (ARAC) program at the Lawrence Livermore National Laboratory (LLNL) was the U.S. Department of Energy atmospheric modeling resource used for the contingency of potential radiological releases during the launch of the Cassini mission. The ARAC Center at LLNL forecasted detailed weather conditions and delivered consequence assessments for potential accident scenarios to NASA before and during launch operations. A key aspect of ARAC� s support was to acquire a variety of meteorological data for use in both forecast and real-time model calculations. ARAC acquired electronically two types of real-time observed meteorological data: 1) the full set of on-site towers and profilers via the Cape Canaveral Air Station (CCAS) Meteorological Interactive Data Display System (MIDDS), and 2) routine regional airport observations (delivered to the ARAC Center from the Air Force Weather Agency). We also used two forecasted data sources: 1) the U.S. Air Force 45th Weather Squadron at CCAS forecasted soundings for launch time, and 2) the Navy Operational Regional Atmospheric Prediction System (NORAPS) prognostic model which ARAC ran over the Cape. The NORAPS runs produced detailed 24-hr forecasts of 3-D wind fields. ARAC used default radiological accident source terms involving the potential destruction of Cassini� s …
Date: October 1, 1998
Creator: Baskett, R. L. & Pace, J. C.
Object Type: Article
System: The UNT Digital Library
ARAC's radiological support of the Cassini Launch (open access)

ARAC's radiological support of the Cassini Launch

The Atmospheric Release Advisory Capability (ARAC) program at the Lawrence Livermore National Laboratory (LLNL) was the U.S. Department of Energy atmospheric modeling resource used for the contingency of potential radiological releases during the launch of the Cassini mission. Having the ARAC system up and running was one of the launch criteria during the countdown. The ARAC Center at LLNL forecasted detailed weather conditions and delivered consequence assessments for potential accident scenarios to NASA before and during launch operations. A key aspect of ARAC's support was to acquire a variety of meteorological data for use in both forecast and real-time model calculations. ARAC acquired electronically two types of real-time observed meteorological data: 1) the set of on-site tower and profiler data via the Cape Canaveral Air Station (CCAS) Meteorological Interactive Data Display System (MIDDS), and 2) routine regional airport observations delivered to the ARAC Center from the Air Force Weather Agency. We also used two forecasted data sources: 1) the U.S. Air Force 45th Weather Squadron at CCAS forecasted soundings for launch time, and 2) the Navy Operational Regional Atmospheric Prediction System (NORAPS) prognostic model which ARAC ran over the Cape. The NORAPS runs produced detailed 24-hr forecasts of 3-D wind …
Date: October 1, 1998
Creator: Baskett, R. L. & Pace, J. C.
Object Type: Article
System: The UNT Digital Library
Archer County News (Archer City, Tex.), No. 40, Ed. 1 Thursday, October 1, 1998 (open access)

Archer County News (Archer City, Tex.), No. 40, Ed. 1 Thursday, October 1, 1998

Weekly newspaper from Archer City, Texas that includes local, state and national news along with advertising.
Date: October 1, 1998
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Area G Perimeter Surface-Soil and Single-Stage Water Sampling: Environmental Surveillance for Fiscal Years 1996 and 1997, Group ESH-19 (open access)

Area G Perimeter Surface-Soil and Single-Stage Water Sampling: Environmental Surveillance for Fiscal Years 1996 and 1997, Group ESH-19

Area Gin Technical Area 54, has been the principal facility at Los Alamos National Laboratory for the storage and disposal of low-level, solid mixed, and transuranic radioactive waste since 1957. Soil samples were analyzed for tritium, isotopic plutonium, americium-241, and cesium-137. Thirteen metals-silver, arsenic, barium, beryllium, cadmium, chromium, mercury, nickel, lead, antimony, selenium, thallium and zinc-were analyzed on filtered-sediment fractions of the single-stage samples using standard analytical chemistry techniques. During the two years of sampling discussed in this report elevated levels of tritium (as high as 716,000 pCi/L) in soil were found for sampling sites adjacent to the tritium burial shafts located on the south- central perimeter of Area G. Additionally, tritium concentrations in soil as high as 38,300 pCi/L were detected adjacent to the TRU pads in the northeast comer of Area G. Plutonium-238 activities in FY96 soils ranged from 0.001-2.866 pCi/g, with an average concentration of 0.336& 0.734 pCdg. Pu-238 activities in FY97 soils ranged from 0.002-4.890 pCi/g, with an average concentration of 0.437 & 0.928 pCdg. Pu-239 activities in FY96 soils ranged from 0.009 to 1.62 pCdg, with an average of 0.177- 0.297 pCdg. Pu-239 activities in FY97 soils ranged from 0.005 to 1.71 pCi/g, with an …
Date: October 1, 1998
Creator: Childs, Marquis & Conrad, Ron
Object Type: Report
System: The UNT Digital Library
Area-normalized thematic views (open access)

Area-normalized thematic views

This paper presents a novel technique for dealing with a classic problem that frequently arises in visualization. Very expressive nonlinear transformations can be automatically generated to correct thematic maps so that the areas of map regions are proportional to the thematic variables assigned to them. This helps to eliminate one of the most commonly occurring visual lies that occurs in information visualization. Thematic variables are commonly used in cartography to encode additional information within the spatial layout of a map. Common examples of thematic variables are population density, pollution level and birth rate. The method is illustrated with two examples, mapping interstate speed limits and presidential election results.
Date: October 1, 1998
Creator: Keahey, T.A.
Object Type: Article
System: The UNT Digital Library
Assessment of the Meteorological Characterization Used in the ADROIT Code (open access)

Assessment of the Meteorological Characterization Used in the ADROIT Code

The ADROIT Analysis of Dispersal Risk Qccurring in transportation code is the primary tool used to perform probabilistic risk assessments for the Transportation Safeguards Division of the Department of Energy. The current version of ADROIT uses a Pasquill-Gifford stability-class approach to meteorological characterization. In order to assess the affect that this simplified approach to weather characterization has on ADROIT'S predictions of consequence and risk, the Pasquill-Gifford stability-class approach was replaced with a direct use of radiosonde data from the National Climatic Data Center (NCDC). A comparison of results obtained for the two weather characterizations shows that, under certain circumstances, the use of the stability-class approach can result in a significant underprediction of consequence and risk values. Since such an underprediction is non-consewative, it is recommended that the stability-class approach currently used by ADROIT be replaced with a more detailed characterization of meteorological conditions. Specifically, the NCDC database was found to have sufllcient temporal and spatial resolution for ADROIT applications. Understanding that an attempt to use of all of the NCDC data in ADROIT would be prohibitive, a sampling scheme is presented as a viable alternative for instituting the recommendation of this study.
Date: October 1, 1998
Creator: Ryder, E.E.
Object Type: Report
System: The UNT Digital Library