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Atmospheric Radiation Measurement Program Facilities Newsletter, July 2001. (open access)

Atmospheric Radiation Measurement Program Facilities Newsletter, July 2001.

Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.
Date: July 23, 2001
Creator: Atmospheric Radiation Measurement Program (U.S.)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
National Atmospheric Release Advisory Center Internet Client (NARAC I Client) On-Line Help System Documentation (open access)

National Atmospheric Release Advisory Center Internet Client (NARAC I Client) On-Line Help System Documentation

None
Date: July 23, 2001
Creator: Belles, R.; Fischer, K.; Foster, K.; Foster, C.; Gash, J. & Stewart, J.
Object Type: Text
System: The UNT Digital Library
Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra (open access)

Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra

This paper discusses our efforts to improve the performance of the high-accuracy (HIAC) volume rendering system, based on cell projection, which is used to display unstructured, scientific data sets for analysis. The parallelization of HIAC, using the pthreads and MPI API's, resulted in significant speedup, but interactive frame rates are not yet attainable for very large data sets.
Date: July 23, 2001
Creator: Bennett,J; Cook,R; Max,N; May,D & Williams,P
Object Type: Article
System: The UNT Digital Library
Daily Journal (Perry, Okla.), Vol. 108, No. 143, Ed. 1 Monday, July 23, 2001 (open access)

Daily Journal (Perry, Okla.), Vol. 108, No. 143, Ed. 1 Monday, July 23, 2001

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 23, 2001 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 23, 2001

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 102, No. 122, Ed. 1 Monday, July 23, 2001 (open access)

Altus Times (Altus, Okla.), Vol. 102, No. 122, Ed. 1 Monday, July 23, 2001

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
PHASE II CALDERON PROCESS TO PRODUCE DIRECT REDUCED IRON RESEARCH AND DEVELOPMENT PROJECT (open access)

PHASE II CALDERON PROCESS TO PRODUCE DIRECT REDUCED IRON RESEARCH AND DEVELOPMENT PROJECT

This project was initially targeted to the making of coke for blast furnaces by using proprietary technology of Calderon in a phased approach, and Phase I was completed. The project was then re-directed to the making of iron units. U.S. Steel teamed up with Calderon for a joint effort which will last 30 months to produce directly reduced iron with the potential of converting it into molten iron (hot metal) consistent with the Roadmap recommendations of 1998 prepared by the Steel Industry in cooperation with the Department of Energy. The work which is labeled as Phase II will take place at two levels; namely, the bench scale level and the process development unit level. During the past quarter approval for the re-direction took place and work was initiated at both levels.
Date: July 23, 2001
Creator: Calderon, Albert
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 239, Ed. 1 Monday, July 23, 2001 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 239, Ed. 1 Monday, July 23, 2001

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Implications of the Drift Scale Heater Test at Yucca Mountain for Epithermal Mineralization (open access)

Implications of the Drift Scale Heater Test at Yucca Mountain for Epithermal Mineralization

An 8-year long, drift scale heater test (DST) is currently underway at the underground Exploratory Studies Facility at Yucca Mountain in Nevada. The host rock for the DST is a highly fractured, welded tuff. The rock has {approx}10% matrix porosity 90% filled with water. After a little more than two years of heating, the temperature at the drift wall reached {approx}200 C and has been maintained at that temperature for the past {approx}1.5 years. Gas and water (both vapor and liquid) have been collected from monitoring boreholes since the test began. The CO{sub 2} concentration of the gas and the isotopic compositions of the water and CO{sub 2} are measured. These data are used to constrain numerical models of coupled thermal, hydrological, and chemical processes occurring in the system. Despite obvious differences from epithermal systems (e.g., the DST is being conducted in an unsaturated system), the trends observed in the isotopic compositions of the water and CO{sub 2} have interesting implications for natural systems. In areas below boiling, the isotope ratios of the water are near that of the ambient pore water ({delta}{sup 18}O about -12{per_thousand}). Where significant amounts of vapor condensate occur (above the boiling front above the drift …
Date: July 23, 2001
Creator: Conrad, Mark E. & Sonnenthal, Eric L.
Object Type: Report
System: The UNT Digital Library
The radiation environment in and near high gradient rf cavities. (open access)

The radiation environment in and near high gradient rf cavities.

The radiation environment in and near high gradient rf cavities is very important for the instrumentation of the MUCOOL experiment, since large fluxes of x rays and dark current electrons can interfere with the operation of the muon detectors. We have measured the x ray and dark current spectra from a single cell, 1.3 GHz, and are beginning to make more extensive measurements of a multicelled 805 MHz cavity. The results are consistent with electron field emission, bremsstrahlung and photon absorption/scattering. We discuss ways of minimizing this background and the scaling of these results to other cavities.
Date: July 23, 2001
Creator: Ducas, L.; Norem, J.; Geer, S.; Moretti, A.; Popovic, M. & Solomey, N.
Object Type: Article
System: The UNT Digital Library
A Numerical Analysis of the Single-Well Steam Assisted Gravity Drainage (SW-SAGD) Process, SUPRI TR-124 (open access)

A Numerical Analysis of the Single-Well Steam Assisted Gravity Drainage (SW-SAGD) Process, SUPRI TR-124

Results from this study include cumulative recoveries, temperature distributions, and production rates. It was found that cyclic steaming of the reservoir offers the most favorable option for heating the near-wellbore area to create conditions that improve initial SAGD response. More favorable reservoir conditions such as low viscosity, thick oil zones, and solution gas, improved reservoir response. Under unfavorable conditions, response was limited.
Date: July 23, 2001
Creator: Elliot, K. T. & Kovscek, A. R.
Object Type: Report
System: The UNT Digital Library
Superlow-friction carbon films for fuel system components operating in low-sulfur diesel fuels. (open access)

Superlow-friction carbon films for fuel system components operating in low-sulfur diesel fuels.

None
Date: July 23, 2001
Creator: Erdemir, A.; Kavich, J.; Woodford, J.; Ajayi, L. & Fenske, G.
Object Type: Article
System: The UNT Digital Library
Visualization of Solution Gas Drive in Viscous Oil, SUPRI TR-126 (open access)

Visualization of Solution Gas Drive in Viscous Oil, SUPRI TR-126

Several experimental studies of solution gas drive are available in this report. Almost all of the studies have used light oil. Solution gas drive behavior, especially in heavy oil reservoirs, is poorly understood. Experiments were performed in which pore-scale solution gas drive phenomena were viewed in water/carbon dioxide and viscous oil/carbon dioxide systems. A new pressure vessel was designed and constructed to house silicon-wafer micromodels that previously operated at low (<3 atm) pressure. The new apparatus is used for the visual studies. Several interesting phenomena were viewed. The repeated nucleation of gas bubbles was observed at a gas-wet site occupied by dirt. Interestingly, the dissolution of a gas bubble into the liquid phase was previously recorded at the same nucleation site. Gas bubbles in both systems grew to span one ore more pore bodies before mobilization. Liquid viscosity affected the ease with which gas bubbles coalesced. More viscous solutions result in slower rates of coalescence. The transport of solid particles on gas-liquid interfaces was also observed.
Date: July 23, 2001
Creator: George, D. S. & Kovscek, A. R.
Object Type: Report
System: The UNT Digital Library
High power test of the first s-band rf gun at SRRC. (open access)

High power test of the first s-band rf gun at SRRC.

We had constructed an S-band high power rf system at SRRC (Synchrotron Radiation Research Center). It will be used as a test bench of various designs of S-band rf guns. A 2856 MHz PFN (Pulse Forming Network) system was built to deliver 2 {micro}s, 40KV voltage pulse at 10Hz repetition rate for the XK-5 Klystron. As a quick start, we had fabricated a 2856MHz single cell rf gun for the high power test. The recent results are reported.
Date: July 23, 2001
Creator: Ho, C. H.; Chang, S. S.; Chiou, J. P.; Fann, C. S.; Hsu, K. T.; Hsu, S. Y. et al.
Object Type: Article
System: The UNT Digital Library
[News Clip: Hewlett Packard Layoffs] captions transcript

[News Clip: Hewlett Packard Layoffs]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: July 23, 2001, 4:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
Determination of an Initial Mesh Density for Finite Element Computations via Data Mining (open access)

Determination of an Initial Mesh Density for Finite Element Computations via Data Mining

Numerical analysis software packages which employ a coarse first mesh or an inadequate initial mesh need to undergo a cumbersome and time consuming mesh refinement studies to obtain solutions with acceptable accuracy. Hence, it is critical for numerical methods such as finite element analysis to be able to determine a good initial mesh density for the subsequent finite element computations or as an input to a subsequent adaptive mesh generator. This paper explores the use of data mining techniques for obtaining an initial approximate finite element density that avoids significant trial and error to start finite element computations. As an illustration of proof of concept, a square plate which is simply supported at its edges and is subjected to a concentrated load is employed for the test case. Although simplistic, the present study provides insight into addressing the above considerations.
Date: July 23, 2001
Creator: Kanapady, R; Bathina, S K; Tamma, K K; Kamath, C & Kumar, V
Object Type: Article
System: The UNT Digital Library
Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues (open access)

Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues

Natural attenuation processes are commonly used for remediation of contaminated sites. A variety of natural processes occur without human intervention at all sites to varying rates and degrees of effectiveness to attenuate (decrease) the mass, toxicity, mobility, volume, or concentration of organic and inorganic contaminants in soil, groundwater, and surface water systems. The objective of this review is to identify potential technical investments to be incorporated in the Subsurface Contaminant Focus Area Strategic Plan for monitored natural attenuation. When implemented, the technical investments will help evaluate and implement monitored natural attenuation as a remediation option at DOE sites. The outcome of this review is a set of conclusions and general recommendations regarding research needs, programmatic guidance, and stakeholder issues pertaining to monitored natural attenuation for the DOE complex.
Date: July 23, 2001
Creator: Krupka, Kenneth M & Martin, Wayne J
Object Type: Report
System: The UNT Digital Library
Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues (open access)

Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues

Natural attenuation processes are commonly used for remediation of contaminated sites. A variety of natural processes occur without human intervention at all sites to varying rates and degrees of effectiveness to attenuate (decrease) the mass, toxicity, mobility, volume, or concentration of organic and inorganic contaminants in soil, groundwater, and surface water systems. The objective of this review is to identify potential technical investments to be incorporated in the Subsurface Contaminant Focus Area Strategic Plan for monitored natural attenuation. When implemented, the technical investments will help evaluate and implement monitored natural attenuation as a remediation option at DOE sites. The outcome of this review is a set of conclusions and general recommendations regarding research needs, programmatic guidance, and stakeholder issues pertaining to monitored natural attenuation for the DOE complex.
Date: July 23, 2001
Creator: Krupka, Kenneth M. & Martin, Wayne J.
Object Type: Report
System: The UNT Digital Library
Simulating the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada (open access)

Simulating the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada

Heat transfer within Earth's upper crust is primarily by conduction, and conductive thermal models adequately explain the cooling history of deep, batholith-scale intrusions and surrounding wall rocks, as confirmed by numerous thermochronometric studies. However, caldera magmatic systems require consideration of the small and localized component of hydrothermal convection and numerical models to simulate additional boundary conditions, irregular magma chamber shapes, and complex intrusive histories. At Yucca Mountain, Nevada, the site of a potential high-level nuclear waste repository, simulating the detailed thermal history at any location in the unsaturated zone requires knowledge of the shape of the magma chamber and its proximity to Yucca Mountain (the southern margin of the Timber Mountain caldera complex is approximately 8 km north of the potential repository site), the temporal and spatial extent of hydrothermal convection, the erosional history of the area, and past levels of the water table.
Date: July 23, 2001
Creator: Marshal, B. D. & Whelan, J. F.
Object Type: Report
System: The UNT Digital Library
Antenna-coupled arrays of voltage-biased superconducting bolometers (open access)

Antenna-coupled arrays of voltage-biased superconducting bolometers

We report on the development of antenna-coupled Voltage-biased Superconducting Bolometers (VSBs) which use Transition-edge Sensors (TES). Antenna coupling can greatly simplify the fabrication of large multi-frequency bolometer arrays compared to horn-coupled techniques. This simplification can make it practical to implement 1000+ element arrays that fill the focal plane of mm/sub-mm wave telescopes. We have designed a prototype device with a double-slot dipole antenna, integrated band-defining filters, and a membrane-suspended bolometer. A test chip has been constructed and will be tested shortly.
Date: July 23, 2001
Creator: Myers, Michael J.; Lee, Adrian T.; Richards, P. L.; Schwan, D.; Skidmore, J. T.; Smith, A. D. et al.
Object Type: Article
System: The UNT Digital Library
Global Static Indexing for Real-Time Exploration of Very Large Regular Grids (open access)

Global Static Indexing for Real-Time Exploration of Very Large Regular Grids

In this paper we introduce a new indexing scheme for progressive traversal and visualization of large regular grids. We demonstrate the potential of our approach by providing a tool that displays at interactive rates planar slices of scalar field data with very modest computing resources. We obtain unprecedented results both in terms of absolute performance and, more importantly, in terms of scalability. On a laptop computer we provide real time interaction with a 2048{sup 3} grid (8 Giga-nodes) using only 20MB of memory. On an SGI Onyx we slice interactively an 8192{sup 3} grid (1/2 tera-nodes) using only 60MB of memory. The scheme relies simply on the determination of an appropriate reordering of the rectilinear grid data and a progressive construction of the output slice. The reordering minimizes the amount of I/O performed during the out-of-core computation. The progressive and asynchronous computation of the output provides flexible quality/speed tradeoffs and a time-critical and interruptible user interface.
Date: July 23, 2001
Creator: Pascucci, V & Frank, R
Object Type: Article
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 267, Ed. 1 Monday, July 23, 2001 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 267, Ed. 1 Monday, July 23, 2001

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Damage Prediction and Estimation in Structural Mechanics Based on Data Mining (open access)

Damage Prediction and Estimation in Structural Mechanics Based on Data Mining

Damage in a material includes localized softening or cracks in a structural component due to high operational loads, or the presence of flaws in a structure due to various manufacturing processes. Methods that identify the presence, the location and the severity of damage in the structure are useful for non-destructive evaluation procedures that are typically employed in agile manufacturing and rapid prototyping systems. The current state-of-the art techniques for these inverse problems are computationally intensive or ill conditioned when insufficient data exists. Early work by a number of researchers has shown that data mining techniques can provide a potential solution to this problem. In this paper, they investigate the use of data mining techniques for predicting failure in a variety of 2D and 3D structures using artificial neural networks (ANNs) and decision trees. This work shows that if the correct features are chosen to build the model, and the model is trained on an adequate amount of data, the model can then correctly classify the failure event as well as predict location and severity of the damage in these structures.
Date: July 23, 2001
Creator: Sandhu, S S; Kanapady, R; Tamma, K K; Kamath, C & Kumar, V
Object Type: Article
System: The UNT Digital Library
Spent Fuel Criticality Benchmark Experiments (open access)

Spent Fuel Criticality Benchmark Experiments

Characteristics between commercial spent fuel waste packages (WP), Laboratory Critical Experiments (LCEs), and commercial reactor critical (CRC) evaluations are compared in this work. Emphasis is placed upon comparisons of CRC benchmark results and the relative neutron flux spectra in each system. Benchmark evaluations were performed for four different pressurized water reactors using four different sets of isotopes. As expected, as the number of fission products used to represent the burned fuel inventory approached reality, the closer to unity k{sub eff} became. Examination of material and geometry characteristics indicate several fundamental similarities between the WP and CRC systems. In addition, spectral evaluations were performed on a representative pressurized water reactor CRC, a 21-assembly area of the core modeled in a potential WP configuration, and three LCEs considered applicable benchmarks for storage packages. Fission and absorption reaction spectra as well as relative neutron flux spectra are generated and compared for each system. The energy dependent reaction rates are the product of the neutron flux spectrum and the energy dependent total macroscopic cross section. With constant source distribution functions, and the total macroscopic cross sections for the fuel region in the CRCs and WP being composed of nearly the same isotopics, the resulting …
Date: July 23, 2001
Creator: Scaglione, J.M.
Object Type: Report
System: The UNT Digital Library