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SIAM Workshop on Combinatorial Scientific Computing February 27-28, 2004 San Francisco, CA
None
Date:
October 4, 2004
Creator:
/a, n
Object Type:
Report
System:
The UNT Digital Library
MODELING FLOW AND TRANSPORT PATHWAYS TO THE POTENTIAL REPOSITORY HORIZON AT YUCCA MOUNTAIN
The isotopic ratios of {sup 36}Cl/Cl are used in conjunction with geologic interpretation and numerical modeling to evaluate flow and transport pathways, processes, and model parameters in the unsaturated zone at Yucca Mountain. By synthesizing geochemical and geologic data, the numerical model results provide insight into the validity of alternative hydrologic parameter sets, flow and transport processes in and away from fault zones, and the applicability of {sup 36}Cl/Cl. ratios for evaluating alternative conceptual models.
Date:
March 4, 1998
Creator:
A.V. WOLFSBERG, G.J.C. ROEMER, J.T. FABRYKA-MARTIN, B.A. ROBINSON
Object Type:
Report
System:
The UNT Digital Library
HIGH ALUMINUM HLW (HIGH LEVEL WASTE ) GLASSES FOR HANFORDS WTP (WASTE TREATMENT PROJECT)
This paper presents the results of glass formulation development and melter testing to identify high waste loading glasses to treat high-Al high level waste (HLW) at Hanford. Previous glass formulations developed for this HLW had high waste loadings but their processing rates were lower that desired. The present work was aimed at improving the glass processing rate while maintaining high waste loadings. Glass formulations were designed, prepared at crucible-scale and characterized to determine their properties relevant to processing and product quality. Glass formulations that met these requirements were screened for melt rates using small-scale tests. The small-scale melt rate screening included vertical gradient furnace (VGF) and direct feed consumption (DFC) melter tests. Based on the results of these tests, modified glass formulations were developed and selected for larger scale melter tests to determine their processing rate. Melter tests were conducted on the DuraMelter 100 (DMIOO) with a melt surface area of 0.11 m{sup 2} and the DuraMelter 1200 (DMI200) HLW Pilot Melter with a melt surface area of 1.2 m{sup 2}. The newly developed glass formulations had waste loadings as high as 50 wt%, with corresponding Al{sub 2}O{sub 3} concentration in the glass of 26.63 wt%. The new glass formulations …
Date:
January 4, 2010
Creator:
AA, KRUGER; BW, BOWAN; I, JOSEPH; H, GAN; WK, KOT; KS, MATLACK et al.
Object Type:
Article
System:
The UNT Digital Library
MELT RATE ENHANCEMENT FOR HIGH ALUMINUM HLW (HIGH LEVEL WASTE) GLASS FORMULATION FINAL REPORT 08R1360-1
This report describes the development and testing of new glass formulations for high aluminum waste streams that achieve high waste loadings while maintaining high processing rates. The testing was based on the compositions of Hanford High Level Waste (HLW) with limiting concentrations of aluminum specified by the Office of River Protection (ORP). The testing identified glass formulations that optimize waste loading and waste processing rate while meeting all processing and product quality requirements. The work included preparation and characterization of crucible melts and small scale melt rate screening tests. The results were used to select compositions for subsequent testing in a DuraMelter 100 (DM100) system. These tests were used to determine processing rates for the selected formulations as well as to examine the effects of increased glass processing temperature, and the form of aluminum in the waste simulant. Finally, one of the formulations was selected for large-scale confirmatory testing on the HLW Pilot Melter (DM1200), which is a one third scale prototype of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) HLW melter and off-gas treatment system. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for Department of Energy (DOE) to increase waste loading …
Date:
January 4, 2010
Creator:
AA, KRUGER; KS, MATLACK; W, KOT; IL, PEGG; I, JOSEPH; T, BARDAKCI et al.
Object Type:
Report
System:
The UNT Digital Library
Measurement of the Differential Cross-Sections of Inclusive, Prompt And Non-Prompt $J/\psi$ Production in Proton-Proton Collisions at $\sqrt{s}=7$ TeV
None
Date:
June 4, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Ground motion modeling of Hayward fault scenario earthquakes II:Simulation of long-period and broadband ground motions
We simulate long-period (T > 1.0-2.0 s) and broadband (T > 0.1 s) ground motions for 39 scenarios earthquakes (Mw 6.7-7.2) involving the Hayward, Calaveras, and Rodgers Creek faults. For rupture on the Hayward fault we consider the effects of creep on coseismic slip using two different approaches, both of which reduce the ground motions compared with neglecting the influence of creep. Nevertheless, the scenario earthquakes generate strong shaking throughout the San Francisco Bay area with about 50% of the urban area experiencing MMI VII or greater for the magnitude 7.0 scenario events. Long-period simulations of the 2007 Mw 4.18 Oakland and 2007 Mw 4.5 Alum Rock earthquakes show that the USGS Bay Area Velocity Model version 08.3.0 permits simulation of the amplitude and duration of shaking throughout the San Francisco Bay area, with the greatest accuracy in the Santa Clara Valley (San Jose area). The ground motions exhibit a strong sensitivity to the rupture length (or magnitude), hypocenter (or rupture directivity), and slip distribution. The ground motions display a much weaker sensitivity to the rise time and rupture speed. Peak velocities, peak accelerations, and spectral accelerations from the synthetic broadband ground motions are, on average, slightly higher than the …
Date:
November 4, 2009
Creator:
Aagaard, B T; Graves, R W; Rodgers, A; Brocher, T M; Simpson, R W; Dreger, D et al.
Object Type:
Article
System:
The UNT Digital Library
Federal energy organization
This report presents information about Federal energy organization for handling the energy issues with in nation's interest.
Date:
March 4, 1975
Creator:
Abbasi, Susan R.
Object Type:
Report
System:
The UNT Digital Library
Measurement of the 8B Solar Neutrino Flux with KamLAND
We report a measurement of the neutrino-electron elastic scattering rate from {sup 8}B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5-MeV analysis threshold is 1.49 {+-} 0.14(stat) {+-} 0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a {sup 8}B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77 {+-} 0.26(stat) {+-} 0.32(syst) x 10{sup 6} cm{sup -2}s{sup -1}. The analysis threshold is driven by {sup 208}Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic {sup 11}Be. The measured rate is consistent with existing measurements and with standard solar model predictions which include matter-enhanced neutrino oscillation.
Date:
June 4, 2011
Creator:
Abe, S.; Furuno, K.; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H. et al.
Object Type:
Article
System:
The UNT Digital Library
Electricity Restructuring Background: The Public Utility Regulatory Policies Act of 1978 and the Energy Policy Act of 1992
None
Date:
May 4, 1998
Creator:
Abel, Amy
Object Type:
Report
System:
The UNT Digital Library
Electricity Restructuring Background: The Public Utility Regulatory Policies Act of 1978 and the Energy Policy Act of 1992
The Energy Policy Act of 1992 (EPACT) increased competition in the electric generating sector by creating new entities that can generate and sell electricity at wholesale without being regulated as utilities under PUHCA. PURPA began to shift more regulatory responsibilities to the federal government, and EPACT continued that shift away from the states by creating new options for utilities and regulators to meet electricity demand.
Date:
May 4, 1998
Creator:
Abel, Amy
Object Type:
Report
System:
The UNT Digital Library
Government Activities to Protect the Electric Grid
None
Date:
February 4, 2005
Creator:
Abel, Amy
Object Type:
Report
System:
The UNT Digital Library
Government Activities to Protect the Electric Grid
This report provides a description of initiatives within the Federal Energy Regulatory Commission and the Departments of Energy, Homeland Security, and Defense to protect the physical electrical utility infrastructure from outages caused by a range of activities including system operator errors, weather-related damage, and terrorist attacks. While the electric utility industry has primary responsibility, federal and state government agencies also have been addressing physical security concerns.
Date:
February 4, 2005
Creator:
Abel, Amy
Object Type:
Report
System:
The UNT Digital Library
The Neutron Sensitive PCP Ionization Chamber
Manual of operation for a neutron sensitive ionization chamber for reactor instrumentation.
Date:
September 4, 1951
Creator:
Abele, R. K. & Gundlach, J.
Object Type:
Report
System:
The UNT Digital Library
Wet Chemical Etching Survey of III-Nitrides
Wet chemical etching of GaN, InN, AlN, InAlN and InGaN was investigated in various acid and base solutions at temperatures up to 75 C. Only KOH-based solutions were found to etch AlN and InAlN. No etchants were found for the other nitrides, emphasizing their extreme lack of chemical reactivity. The native oxide on most of the nitrides could be removed in potassium tetraborate at 75 C, or HCl/H{sub 2}O at 25 C.
Date:
February 4, 1999
Creator:
Abernathy, C. R.; Cho, H.; Hays, D. C.; MacKenzie, J. D.; Pearton, S.J.; Ren, F. et al.
Object Type:
Article
System:
The UNT Digital Library
Inductively Coupled Plasma Etching of III-V Semiconductors in BCl(3)-Based Chemistries: Part 1: GaAs, GaN, GaP, GaSb and AlGaAs
BC13, with addition of Nz, Ar or Hz, is found to provide smooth anisotropic pattern transfer in GaAs, GaN, GaP, GaSb and AIGriAs under Inductively Coupled Plasma conditions, Maxima in the etch rates for these materials are observed at 33% N2 or 87$'40 Hz (by flow) addition to BC13, whereas Ar addition does not show this behavior. Maximum etch rates are typically much higher for GaAs, Gap, GaSb and AIGaAs (-1,2 @rein) than for GaN (-0.3 ymu'min) due to the higher bond energies of the iatter. The rates decrease at higher pressure, saturate with source power (ion flux) and tend to show maxima with chuck power (ion energy). The etched surfaces remain stoichiometric over abroad range of plasma conditions.
Date:
December 4, 1998
Creator:
Abernathy, C.R,; Han, J.; Hobson, W.S.; Hong, J.; Lambers, E.S.; Lee, J.W. et al.
Object Type:
Article
System:
The UNT Digital Library
Inductively Coupled Plasma and Electron Cyclotron Resonance Plasma Etching of InGaAlP Compound Semiconductor System
Current and future generations of sophisticated compound semiconductor devices require the ability for submicron scale patterning. The situation is being complicated since some of the new devices are based on a wider diversity of materials to be etched. Conventional IUE (Reactive Ion Etching) has been prevalent across the industry so far, but has limitations for materials with high bond strengths or multiple elements. IrI this paper, we suggest high density plasmas such as ECR (Electron Cyclotron Resonance) and ICP (Inductively Coupled Plasma), for the etching of ternary compound semiconductors (InGaP, AIInP, AlGaP) which are employed for electronic devices like heterojunction bipolar transistors (HBTs) or high electron mobility transistors (HEMTs), and photonic devices such as light-emitting diodes (LEDs) and lasers. High density plasma sources, opeiating at lower pressure, are expected to meet target goals determined in terms of etch rate, surface morphology, surface stoichiometry, selectivity, etc. The etching mechanisms, which are described in this paper, can also be applied to other III-V (GaAs-based, InP-based) as well as III-Nitride since the InGaAIP system shares many of the same properties.
Date:
November 4, 1998
Creator:
Abernathy, C.R.; Hobson, W.S.; Hong, J.; Lambers, E.S.; Pearton, S.J. & Shul, R.J.
Object Type:
Article
System:
The UNT Digital Library
Optical simulation for imaging reconnaissance and intelligence sensors OSIRIS: High fidelity sensor simulation test bed; Modified user`s manual
The OSIRIS program is an imaging optical simulation program which has been developed to predict the output of space-borne sensor systems. The simulation is radiometrically precise and includes highly realistic laser, atmosphere, and earth background models, as well as detailed models of optical components. This system was developed by Rockwell Power Services for the Los Alamos National Laboratory. It is based upon the LARC (Los Alamos Radiometry Code, also by Rockwell), and uses a similar command structure and 3d coordinate system as LARC. At present OSIRIS runs on the Cray I computer under the CTSS operating s stem, and is stored in the OSIRIS root directory on LANL CTSS mass storage.
Date:
January 4, 1988
Creator:
Abernathy, M. F. & Puccetti, M. G.
Object Type:
Report
System:
The UNT Digital Library
Measurement of Neutron Total Cross Sections in Support of the APT Program
The authors have completed a new set of total cross section measurements of 37 samples spanning the periodic table. The authors employed the same technique as in a previous measurement, with refinements intended to allow measurements on separated isotopes, and with improved systematic error control. The goal of the new measurement was 1% statistical accuracy in 1% energy bins with systematic errors less than 1%. This was achieved for all but the smallest samples, for which the statistical accuracy was as large as 2% in 1% bins.
Date:
November 4, 1998
Creator:
Abfalterer, W. P.; Haight, R. C.; Morgan, G. L.; Bateman, F. B.; Dietrich, F. S. & Finlay, R. W.
Object Type:
Article
System:
The UNT Digital Library
Polycube oxidation and factors affecting the concentrations of gaseous products
The polycubes stored at the Hanford Plutonium Finishing Plant (PFP) have been identified in a Vulnerability Assessment as material that requires a stabilization process in support of the Defense Nuclear Facility Safety Board Recommendation 94-1. The baseline plan involves a pyrolysis process to separate out the plutonium and uranium oxides before the remaining material is packaged for interim storage, in accordance with the Record of Decision (ROD), issued June 25, 1996, for the Plutonium Finishing Plant Stabilization Final Environmental Impact Statement, DOE/EIS-0244-F. The polycubes were manufactured at Hanford in the 1960s for use in criticality studies to determine the hydrogen-to-fissile atom ratios for neutron moderation. A mixture of plutonium and/or uranium oxides and a polystyrene (vinyl benzene) matrix, cast into the shape of cubes, the polycubes simulated solutions containing high concentrations of fissile materials. The polycubes varied in size, typically 1/2 x 2 x 2 in. up to 2 x 2 x 2 in., and were sealed with a coating of aluminum paint and/or tape (PVC or Shurtape). The estimated 1,600 polycubes (calculated 179,165 grams net weight) stored at PFP were packed in vented food cans with five to eight cubes per can to accommodate gas generation by radiolysis. Some …
Date:
May 4, 2000
Creator:
Abrefah, J.; MacFarlan, P. J. & Sell, R. L.
Object Type:
Report
System:
The UNT Digital Library
Polycube Oxidation and Factors Affecting the Concentrations of Gaseous Products
The degraded polycube samples were tested in air and argon/oxygen atmospheres to determine the effect of size increase on the flammable gases concentrations. Within the size range tested, the flammable gas generation rate increases with increasing size but the extrapolation of the data to actual processing polycube size yielded flammable gas species concentration in the off-gas stream below the lower flammable limit of all the major gas species identified. Extreme surface area increase with a powder sample showed no significant effect on the flammable gas generation rate. The polycube went through the thermal stabilization process by undergoing both pyrolysis and oxidation generating at the end a plutonium oxide powder that showed unmeasurable weight change at 1273 K.
Date:
April 4, 2000
Creator:
Abrefah, John; MacFarlan, Paul J. & Sell, Rachel L.
Object Type:
Text
System:
The UNT Digital Library
Piston-Liner Crevice Geometry Effect on HCCI Combustion by Multi-Zone Analysis
A multi-zone model has been developed that accurately predicts HCCI combustion and emissions. The multizone methodology is based on the observation that turbulence does not play a direct role on HCCI combustion. Instead, chemical kinetics dominates the process, with hotter zones reacting first, and then colder zones reacting in rapid succession. Here, the multi-zone model has been applied to analyze the effect of piston crevice geometry on HCCI combustion and emissions. Three different pistons of varying crevice size were analyzed. Crevice sizes were 0.26, 1.3 and 2.1 mm, while a constant compression ratio was maintained (17:1). The results show that the multi-zone model can predict pressure traces and heat release rates with good accuracy. Combustion efficiency is also predicted with good accuracy for all cases, with a maximum difference of 5% between experimental and numerical results. Carbon monoxide emissions are underpredicted, but the results are better than those obtained in previous publications. The improvement is attributed to the use of a 40-zone model, while previous publications used a 10-zone model. Hydrocarbon emissions are well predicted. For cylinders with wide crevices (1.3 and 2.1 mm), HC emissions do not decrease monotonically as the relative air/fuel ratio ({lambda}) increases. Instead, maximum HC …
Date:
September 4, 2002
Creator:
Aceves, S. M.; Flowers, D. L.; Espinosa-Loza, F.; Martinez-Frias, J.; Dibble, R. W.; Christensen, M. et al.
Object Type:
Article
System:
The UNT Digital Library
HCCl Combustion: Analysis and Experiments
Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work. On analysis, we have developed two powerful tools: a single zone model and a multi-zone model. The single zone model has proven very successful in predicting start of combustion and providing reasonable estimates for peak cylinder pressure, indicated efficiency and NOX emissions. This model is being applied to develop detailed engine performance maps and control strategies, and to analyze the problem of engine startability. The multi-zone model is capable of very accurate predictions of the combustion process, including HC and CO emissions. The multi-zone model has applicability to the optimization of combustion chamber geometry and operating conditions to achieve controlled combustion at high efficiency and low emissions. On experimental work, we have done a thorough evaluation of operating conditions in a 4-cylinder Volkswagen TDI engine. The engine has been operated over a wide range of conditions by adjusting the intake …
Date:
May 4, 2001
Creator:
Aceves, S. M.; Flowers, D. L.; Martinez-Frias, J.; Smith, J. R.; Dibble, R.; Au, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Accelerations in fighter-airplane crashes
From Introduction: "This report describes some measurements of these quantities obtained by crashing fighter aircraft under circumstances approximating those observed in service."
Date:
November 4, 1957
Creator:
Acker, Loren W.; Black, Dugald O. & Moser, Jacob C.
Object Type:
Report
System:
The UNT Digital Library
The Constitutional Boundaries of Public Aid to Sectarian Elementary and Secondary Schools: An Analysis of Wolman v. Walter
This report contains information regarding the Supreme Court case of Wolman v. Waltman, where it addresses the boundaries of constitutional aid for public schools.
Date:
August 4, 1977
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library