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3-D Numerical Modeling of a Complex Salt Structure (open access)

3-D Numerical Modeling of a Complex Salt Structure

Reliably processing, imaging, and interpreting seismic data from areas with complicated structures, such as sub-salt, requires a thorough understanding of elastic as well as acoustic wave propagation. Elastic numerical modeling is an essential tool to develop that understanding. While 2-D elastic modeling is in common use, 3-D elastic modeling has been too computationally intensive to be used routinely. Recent advances in computing hardware, including commodity-based hardware, have substantially reduced computing costs. These advances are making 3-D elastic numerical modeling more feasible. A series of example 3-D elastic calculations were performed using a complicated structure, the SEG/EAGE salt structure. The synthetic traces show that the effects of shear wave propagation can be important for imaging and interpretation of images, and also for AVO and other applications that rely on trace amplitudes. Additional calculations are needed to better identify and understand the complex wave propagation effects produced in complicated structures, such as the SEG/EAGE salt structure.
Date: February 17, 2000
Creator: House, L.; Larsen, S. & Bednar, J. B.
Object Type: Article
System: The UNT Digital Library
Aequorin as a bioluminescent indicator for use in the determination of biomolecules in single cells. Final technical report (open access)

Aequorin as a bioluminescent indicator for use in the determination of biomolecules in single cells. Final technical report

During this funding period, the laboratories of Drs. Anderson and Daunert have performed a considerable amount of work toward addressing the issues associated with small volume analysis necessary for single cell studies. In that respect, their research has been focused on (1) developing new assays that can be miniaturized and are suitable for small volume and single cell analysis; (2) fabricating pL-vials that simulate the volume of single cells and setting up instrumentation capable of low-volume detection; (3) developing reproducible and reliable microinjection techniques; (4) developing methods of analysis for biomolecules in the pL-vials and employing these assays in the detection of biomolecules in single cells. The accomplishments attained in all these areas are described below. A total of 24 publications and 35 presentations have resulted from this work.
Date: February 17, 2000
Creator: Daunert, Sylvia
Object Type: Report
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 124, No. 38, Ed. 1 Thursday, February 17, 2000 (open access)

The Albany News (Albany, Tex.), Vol. 124, No. 38, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: February 17, 2000
Creator: Lucas, Donnie A.
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 100, No. 285, Ed. 1 Thursday, February 17, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 285, Ed. 1 Thursday, February 17, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Am/Cm Canister Temperature Evaluation in Cim5 (open access)

Am/Cm Canister Temperature Evaluation in Cim5

To facilitate the evaluation of alternate canister designs, 2 canisters were outfitted with thermocouples at elevations of 1/2, 3 1/2, and 6 1/2 inches from the canister bottom. The canisters were fabricated from two inch diameter schedule 10 and two inch diameter schedule 40 stainless steel pipe. Each canister was filled with approximately 2 kilograms of 49 wt percent lanthanide (Ln) loaded 25SrABS glass during 5 inch Cylindrical Induction Melter (CIM5) runs for TTR Tasks 3.03 and 4.03. Melter temperature, total mass of glass poured, and the glass pour rates were almost identical in both runs. The schedule 40 canister has a slightly smaller ID compared to the schedule 10 canister and therefore filled to a level of 9.5 inches compared to 8.0 inches for the schedule 40 canister. The schedule 40 canister had an empty mass of 1906 grams compared to 919 grams for the schedule 10 canister. The schedule 10 canister was found to have a higher maximum surface temperature by about 50--100 C (depending on height) during the glass pour compared to the schedule 40 canister. The additional thermal mass of the schedule 40 canister accounts for this difference. Once filled with glass, each of the canisters …
Date: February 17, 2000
Creator: Baich, M. A.
Object Type: Report
System: The UNT Digital Library
Archer County News (Archer City, Tex.), No. 7, Ed. 1 Thursday, February 17, 2000 (open access)

Archer County News (Archer City, Tex.), No. 7, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
Automatic scheme selection for toolkit hex meshing (open access)

Automatic scheme selection for toolkit hex meshing

Current hexahedral mesh generation techniques rely on a set of meshing tools, which when combined with geometry decomposition leads to an adequate mesh generation process. Of these tools, sweeping tends to be the workhorse algorithm, accounting for at least 50% of most meshing applications. Constraints which must be met for a volume to be sweepable are derived, and it is proven that these constraints are necessary but not sufficient conditions for sweepability. This paper also describes a new algorithm for detecting extruded or sweepable geometries. This algorithm, based on these constraints, uses topological and local geometric information, and is more robust than feature recognition-based algorithms. A method for computing sweep dependencies in volume assemblies is also given. The auto sweep detect and sweep grouping algorithms have been used to reduce interactive user time required to generate all-hexahedral meshes by filtering out non-sweepable volumes needing further decomposition and by allowing concurrent meshing of independent sweep groups. Parts of the auto sweep detect algorithm have also been used to identify independent sweep paths, for use in volume-based interval assignment.
Date: February 17, 2000
Creator: White, David R. & Tautges, Timothy J.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 94, Ed. 1 Thursday, February 17, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 94, Ed. 1 Thursday, February 17, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam Control for Ion Induction Accelerators (open access)

Beam Control for Ion Induction Accelerators

Coordinated bending and acceleration of an intense space-charge-dominated ion beam has been achieved for the first time. This required the development of a variable waveform, precision, bi-polar high voltage pulser and a precision, high repetition rate induction core modulator. Waveforms applied to the induction cores accelerate the beam as the bi-polar high voltage pulser delivers a voltage ramp to electrostatic dipoles which bend the beam through a 90 degree permanent magnet quadrupole lattice. Further work on emittance minimization is also reported.
Date: February 17, 2000
Creator: Sangster, T.C. & Ahle, L.
Object Type: Report
System: The UNT Digital Library
Bogata News (Bogata, Tex.), Vol. 89, No. 40, Ed. 1 Thursday, February 17, 2000 (open access)

Bogata News (Bogata, Tex.), Vol. 89, No. 40, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Bogata, Texas that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Nichols, Nanalee & Nichols, Thomas
Object Type: Newspaper
System: The Portal to Texas History
The Canadian Record (Canadian, Tex.), Vol. 110, No. 7, Ed. 1 Thursday, February 17, 2000 (open access)

The Canadian Record (Canadian, Tex.), Vol. 110, No. 7, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Canadian, Texas that includes local, state and national news along with extensive advertising.
Date: February 17, 2000
Creator: Ezzell, Nancy & Brown, Laurie Ezzell
Object Type: Newspaper
System: The Portal to Texas History
Cap plasticity models and compactive and dilatant pre-failure deformation (open access)

Cap plasticity models and compactive and dilatant pre-failure deformation

At low mean stresses, porous geomaterials fail by shear localization, and at higher mean stresses, they undergo strain-hardening behavior. Cap plasticity models attempt to model this behavior using a pressure-dependent shear yield and/or shear limit-state envelope with a hardening or hardening/softening elliptical end cap to define pore collapse. While these traditional models describe compactive yield and ultimate shear failure, difficulties arise when the behavior involves a transition from compactive to dilatant deformation that occurs before the shear failure or limit-state shear stress is reached. In this work, a continuous surface cap plasticity model is used to predict compactive and dilatant pre-failure deformation. During loading the stress point can pass freely through the critical state point separating compactive from dilatant deformation. The predicted volumetric strain goes from compactive to dilatant without the use of a non-associated flow rule. The new model is stable in that Drucker's stability postulates are satisfied. The study has applications to several geosystems of current engineering interest (oil and gas reservoirs, nuclear waste repositories, buried targets, and depleted reservoirs for possible use for subsurface sequestration of greenhouse gases).
Date: February 17, 2000
Creator: FOSSUM,ARLO F. & FREDRICH,JOANNE T.
Object Type: Article
System: The UNT Digital Library
Characteristics of GaAsSb single quantum well lasers emitting near 1.3 {micro}m (open access)

Characteristics of GaAsSb single quantum well lasers emitting near 1.3 {micro}m

The authors report data on GaAsSb single quantum well lasers grown on GaAs substrates. Room temperature pulsed emission at 1.275 {micro}m in a 1,250 {micro}m-long device has been observed. Minimum threshold current densities of 535 A/cm{sup 2} were measured in 2000 {micro}m long lasers. The authors also measured internal losses of 2--5 cm{sup {minus}1}, internal quantum efficiencies of 30-38% and characteristic temperature T{sub 0} of 67--77 C. From these parameters a gain constant G{sub 0} of 1,660 cm{sup {minus}1} and a transparency current density J{sub tr} of 134 A/cm{sup 2} were calculated. The results indicate the potential for fabricating 1.3 {micro}m VCSELs from these materials.
Date: February 17, 2000
Creator: SPAHN,OLGA B. & KLEM,JOHN F.
Object Type: Article
System: The UNT Digital Library
Cherokeean/Herald (Rusk, Tex.), Vol. 150, No. 52, Ed. 1 Thursday, February 17, 2000 (open access)

Cherokeean/Herald (Rusk, Tex.), Vol. 150, No. 52, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: February 17, 2000
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
Civil Rights Division: Policies and Procedures for Establishing Litigation Priorities, Tracking and Managing Casework, and Disseminating Litigation Results (open access)

Civil Rights Division: Policies and Procedures for Establishing Litigation Priorities, Tracking and Managing Casework, and Disseminating Litigation Results

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Justice's Civil Rights Division's, which uses the abbreviation CRT, management of its responsibilities, focusing on: (1) CRT's role in establishing and coordinating governmentwide civil rights policies and litigation priorities; (2) the division's guidelines, policies, and procedures for tracking and managing its caseload; and (3) the division's guidelines, policies, and procedures for disseminating the results of litigation."
Date: February 17, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
The Colony Courier-Leader (The Colony, Tex.), Vol. 18, No. 43, Ed. 1 Thursday, February 17, 2000 (open access)

The Colony Courier-Leader (The Colony, Tex.), Vol. 18, No. 43, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from The Colony, Texas that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Fleming, Jackie
Object Type: Newspaper
System: The Portal to Texas History
Comanche Chief (Comanche, Tex.), No. 41, Ed. 1 Thursday, February 17, 2000 (open access)

Comanche Chief (Comanche, Tex.), No. 41, Ed. 1 Thursday, February 17, 2000

Weekly newspaper from Comanche, Texas that includes local, state, and national news along with advertising.
Date: February 17, 2000
Creator: Wilkerson, James C., III
Object Type: Newspaper
System: The Portal to Texas History
Congressional Oversight: Opportunities to Address Risks, Reduce Costs, and Improve Performance (open access)

Congressional Oversight: Opportunities to Address Risks, Reduce Costs, and Improve Performance

Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the budget and oversight challenges facing the federal government, focusing on ways to: (1) address activities at risk of fraud, waste, abuse, and mismanagement; (2) improve the economy and efficiency of federal operations; (3) reassess what the federal government does; and (4) redefine the beneficiaries of federal government programs."
Date: February 17, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 266: Area 25 Building 3124 Leachfield, Nevada Test Site, Nevada (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 266: Area 25 Building 3124 Leachfield, Nevada Test Site, Nevada

This Corrective Action Decision Document/Closure Report (CADD/CR) was prepared for Corrective Action Unit (CAU) 266, Area 25 Building 3124 Leachfield, in accordance with the Federal Facility Agreement and Consent Order. Located in Area 25 at the Nevada Test Site in Nevada, CAU 266 includes Corrective Action Site (CAS) 25-05-09. The Corrective Action Decision Document and Closure Report were combined into one report because sample data collected during the corrective action investigation (CAI) indicated that contaminants of concern (COCs) were either not present in the soil, or present at concentrations not requiring corrective action. This CADD/CR identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's recommendation that no corrective action was necessary for CAU 266. From February through May 1999, CAI activities were performed as set forth in the related Corrective Action Investigation Plan. Analytes detected during the three-stage CAI of CAU 266 were evaluated against preliminary action levels (PALs) to determine COCs, and the analysis of the data generated from soil collection activities indicated the PALs were not exceeded for total volatile/semivolatile organic compounds, total petroleum hydrocarbons, polychlorinated biphenyls, total Resource Conservation and Recovery Act metals, gamma-emitting radionuclides, isotopic uranium/plutonium, and strontium-90 for any of the samples. However, …
Date: February 17, 2000
Creator: United States. National Nuclear Security Administration. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Correlation Between Co-60 and X-Ray Exposures on Radiation-Induced Charge Buildup in Silicon-on-Insulator Buried Oxides (open access)

Correlation Between Co-60 and X-Ray Exposures on Radiation-Induced Charge Buildup in Silicon-on-Insulator Buried Oxides

Large differences in charge buildup in SOI buried oxides can result between x-ray and Co-60 irradiations. The effects of bias configuration and substrate type on charge buildup and hardness assurance issues are explored.
Date: February 17, 2000
Creator: Schwank, James R.; Shaneyfelt, Marty R.; Loemker, Rhonda Ann; Draper, Bruce L.; Dodd, Paul E.; Witczak, Steven C. et al.
Object Type: Article
System: The UNT Digital Library
Court Rulings During 1998 on Constitutional Takings Claims Against the United States (open access)

Court Rulings During 1998 on Constitutional Takings Claims Against the United States

This report addresses court rulings during 1998 on Constitutional takings claims against the United States.
Date: February 17, 2000
Creator: Meltz, Robert
Object Type: Report
System: The UNT Digital Library
Criticality Safety Evaluation of Hanford Site High Level Waste Storage Tanks (open access)

Criticality Safety Evaluation of Hanford Site High Level Waste Storage Tanks

This criticality safety evaluation covers operations for waste in underground storage tanks at the high-level waste tank farms on the Hanford site. This evaluation provides the bases for criticality safety limits and controls to govern receipt, transfer, and long-term storage of tank waste. Justification is provided that a nuclear criticality accident cannot occur for tank farms operations, based on current fissile material and operating conditions.
Date: February 17, 2000
Creator: ROGERS, C.A.
Object Type: Report
System: The UNT Digital Library
A direct stiffness-modification approach to attaining linear consistency between incompatible finite element meshes (open access)

A direct stiffness-modification approach to attaining linear consistency between incompatible finite element meshes

In this work, a method is proposed for modifying the standard master-slave stiffness matrix so that linear consistency across the interface of the master and slave meshes is achieved. The existence of such a local stiffness modification is implied by the work of [Dohrmann, et al, to appear]. The present work aims at achieving the same linear consistency through a different method of stiffness modification that is based on simply ensuring zero residual force at the interior interface nodes for all non-zero-stress linear displacement fields and zero residual force at all interface nodes for all rigid-body linear displacement fields. These zero residuals ensure that the local stiffness modification results in an interface that passes the patch test. Numerical examples herein demonstrate that the maximum stress error at the interface goes to zero with the proposed method while it does not for the standard master-slave method.
Date: February 17, 2000
Creator: DRIESSEN,BRIAN
Object Type: Article
System: The UNT Digital Library
Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events (open access)

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.
Date: February 17, 2000
Creator: Aponte, C.I.
Object Type: Report
System: The UNT Digital Library