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3-D Ray-tracing and 2-D Fokker-Planck Simulations of Radiofrequency Application to Tokamak Plasmas (open access)

3-D Ray-tracing and 2-D Fokker-Planck Simulations of Radiofrequency Application to Tokamak Plasmas

A state of the art numerical tool has been developed to simulate the propagation and the absorption of coexisting different types of waves in a tokamak geometry. The code includes a numerical solution of the three-dimensional (R, Z, {Phi}) toroidal wave equation for the electric field of the different waves in the WKBJ approximation. At each step of integration, the two-dimensional (v{sub {parallel}}, v{sub {perpendicular}}) Fokker-Planck equation is solved in the presence of quasilinear diffusion coefficients. The electron Landau damping of the waves is modeled taking into account the interaction of the wave electric fields with the quasilinearly modified distribution function. Consistently, the code calculates the radial profiles of non-inductively generated current densities, the transmitted power traces and the total power damping curves. Synergistic effects among the different type of waves (e.g., lower hybrid and ion Bernstein waves) are studied through the separation of the contributions of the single wave from the effects due to their coexistence.
Date: May 1, 1999
Creator: Cardinali, A.; Paoletti, F. & Bernabei, S.
Object Type: Report
System: The UNT Digital Library
15.4% CuIn1-XGaXSe2-Based Photovoltaic Cells from Solution-Based Precursor Films (open access)

15.4% CuIn1-XGaXSe2-Based Photovoltaic Cells from Solution-Based Precursor Films

We have fabricated 15.4%- and 12.4%-efficient CuIn1-XGaXSe2 (CIGS)-based photovoltaic devices from solution-based electrodeposition (ED) and electroless-deposition (EL) precursors. As-deposited precursors are Cu-rich CIGS. Additional In, Ga, and Se are added to the ED and EL precursor films by physical vapor deposition (PVD) to adjust the final film composition to CuIn1-XGaXSe2. The ED and EL device parameters are compared with those of a recent world record, an 18.8%-efficient PVD device. The tools used for comparison are current voltage, capacitance voltage, and spectral response characteristics.
Date: May 25, 1999
Creator: Bhattacharya, R. N.; Batchelor, W.; Contreras, M. A.; Noufi, R. N. (National Renewable Energy Laboratory); Hiltner, J. F. & Sites, J. R. (Department of Physics, Colorado State University)
Object Type: Article
System: The UNT Digital Library
241-SY-101 data acquisition and control system (DACS) operator interface upgrade operational test report (open access)

241-SY-101 data acquisition and control system (DACS) operator interface upgrade operational test report

This procedure provides instructions for readiness of the first portion of the upgraded 241-SY-101 Data Acquisition and Control System (DACS) computer system to provide proper control and monitoring of the mitigation mixer pump and instrumentation installed in the 241-SY-101 underground storage tank will be systematically evaluated by the performance of this procedure.
Date: May 11, 1999
Creator: Ermi, A. M.
Object Type: Report
System: The UNT Digital Library
242-A evaporator safety analysis report (open access)

242-A evaporator safety analysis report

This report provides a revised safety analysis for the upgraded 242-A Evaporator (the Evaporator). This safety analysis report (SAR) supports the operation of the Evaporator following life extension upgrades and other facility and operations upgrades (e.g., Project B-534) that were undertaken to enhance the capabilities of the Evaporator. The Evaporator has been classified as a moderate-hazard facility (Johnson 1990). The information contained in this SAR is based on information provided by 242-A Evaporator Operations, Westinghouse Hanford Company, site maintenance and operations contractor from June 1987 to October 1996, and the existing operating contractor, Waste Management Hanford (WMH) policies. Where appropriate, a discussion address the US Department of Energy (DOE) Orders applicable to a topic is provided. Operation of the facility will be compared to the operating contractor procedures using appropriate audits and appraisals. The following subsections provide introductory and background information, including a general description of the Evaporator facility and process, a description of the scope of this SAR revision,a nd a description of the basic changes made to the original SAR.
Date: May 17, 1999
Creator: CAMPBELL, T.A.
Object Type: Report
System: The UNT Digital Library
300 Area waste acid treatment system closure plan (open access)

300 Area waste acid treatment system closure plan

The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999.
Date: May 17, 1999
Creator: LUKE, S.N.
Object Type: Report
System: The UNT Digital Library
324 Building fire hazards analysis implementation plan (open access)

324 Building fire hazards analysis implementation plan

In March 1998, the 324 Building Fire Hazards Analysis (FHA) (Reference 1) was approved by the U S. Department of Energy, Richland Operations Office (DOE-RL) for implementation by B and W Hanford Company (BWHC). The purpose of the FHA was to identify gaps in compliance with DOE Order 5480.7A (Reference 2) and Richland Operations Office Implementation Directive (RLID) 5480.7 (Reference 3), especially in regard to loss limitation. The FHA identified compliance gaps in six areas and provided 20 recommendations to bring the 324 Building into compliance with DOE Order 5480 7A. Additionally, one observation was provided. A status is provided for each recommendation in this document. The actions for recommendations associated with the safety related part of the 324 Building and operation of the cells and support areas were evaluated using the Unreviewed Safety Question (USQ) process BWHC will use this Implementation Plan to bring the 324 Building and its operation into compliance with DOE Order 5480 7A and RLID 5480.7.
Date: May 10, 1999
Creator: Barilo, N. F.
Object Type: Report
System: The UNT Digital Library
327 Building fire hazards analysis implementation plan (open access)

327 Building fire hazards analysis implementation plan

In March 1998, the 327 Building Fire Hazards Analysis (FHA) (Reference 1) was approved by the U.S. Department of Energy, Richland Operations Office (DOE-E) for implementation by B and W Hanford Company (BWC). The purpose of the FHA was to identify gaps in compliance with DOE Order 5480.7A (Reference 2) and Richland Operations Office Implementation Directive (RLID) 5480.7 (Reference 3), especially in regard to loss limitation. The FHA identified compliance gaps in five areas and provided nine recommendations (11 items) to bring the 327 Building into compliance. A status is provided for each recommendation in this document. BWHC will use this Implementation Plan to bring the 327 Building and its operation into compliance with DOE Order 5480.7A and IUD 5480.7.
Date: May 10, 1999
Creator: Barilo, N. F.
Object Type: Report
System: The UNT Digital Library
500 CFM portable exhauster temperature and humidity analysis (open access)

500 CFM portable exhauster temperature and humidity analysis

500 cfm portable exhausters will be utilized on single shell tanks involved in saltwell pumping. This will be done, in part, to remove flammable gases from the tank vapor space. The exhaust filter train, fan, stack, and associated instrumentation and equipment are mounted on a portable skid. The design analysis and basis for the skid system design are documented in reference 1. A pumped drainage collection system is being added to the existing portable exhausters. Additional equipment and instrumentation are also being added to the exhausters, including a vacuum pump cabinet and a generic effluent monitoring system (GEMS). The GEMS will provide sampling and monitoring capabilities. The purpose of this analysis is three fold. First, to determine the maximum saltwell tank vapor space temperature. Second, to determine an allowable exhauster inlet air temperature increase to ensure the humidity is less than 70%. Third, to assess potential adverse temperature effects to the continuous air monitor (CAM) sample head. The results of this analysis will be used to ensure that air stream temperatures in the portable exhausters are increased sufficiently to prevent condensation from forming on either the pre or HEPA filters without adversely effecting the CAM.
Date: May 20, 1999
Creator: BIELICKI, B.E.
Object Type: Report
System: The UNT Digital Library
1997 Annual cathodic protection survey report for PFP (open access)

1997 Annual cathodic protection survey report for PFP

This report is the first annual cathodic protection report for PFP. The report documents annual polarization , voltage, amperage, and continuity survey data from 1994 to 1997.
Date: May 18, 1999
Creator: BOWMAN, T.J.
Object Type: Report
System: The UNT Digital Library
1997 Annual cathodic protection survey report for the 242-A evaporator (open access)

1997 Annual cathodic protection survey report for the 242-A evaporator

This report is the first annual cathodic protection report for the 242-A evaporator. The report documents annual polarization survey data and bimonthly rectifier inspection data from 1994 to 1997.
Date: May 18, 1999
Creator: BOWMAN, T.J.
Object Type: Report
System: The UNT Digital Library
1st-Principles Step- and Kink-Formation Energies on Cu(111) (open access)

1st-Principles Step- and Kink-Formation Energies on Cu(111)

In rough agreement with experimental values derived from Cu island shapes vs. temperature, ab-initio calculations yield formation energies of 0.27 and 0.26 eV/ step-edge-atom for (100)- and (111)-micro facet steps on Cu(lll), and 0.09 and 0.12 eV per kink in those steps. Comparison to ab-initio results for Al and Pt shows that as a rule, the average formation energy of straight steps on a close-packed metal surface equals -7% of the metal's cohesive energy.
Date: May 26, 1999
Creator: Feibelman, Peter J.
Object Type: Article
System: The UNT Digital Library
3D unstructured mesh ALE hydrodynamics with the upwind discontinuous galerkin method (open access)

3D unstructured mesh ALE hydrodynamics with the upwind discontinuous galerkin method

The authors describe a numerical scheme to solve 3D Arbitrary Lagrangian-Eulerian (ALE) hydrodynamics on an unstructured mesh using a discontinuous Galerkin method (DGM) and an explicit Runge-Kutta time discretization. Upwinding is achieved through Roe's linearized Riemann solver with the Harten-Hyman entropy fix. For stabilization, a 3D quadratic programming generalization of van Leer's 1D minmod slope limiter is used along with a Lapidus type artificial viscosity. This DGM scheme has been tested on a variety of hydrodynamic test problems and appears to be robust making it the basis for the integrated 3D inertial confinement fusion modeling code (ICF3D). For efficient code development, they use C++ object oriented programming to easily separate the complexities of an unstructured mesh from the basic physics modules. ICF3D is fully parallelized using domain decomposition and the MPI message passing library. It is fully portable. It runs on uniprocessor workstations and massively parallel platforms with distributed and shared memory.
Date: May 7, 1999
Creator: Kershaw, D S; Milovich, J L; Prasad, M K; Shaw, M J & Shestakov, A I
Object Type: Article
System: The UNT Digital Library
[Acceptance of Marcus Fellowship: Academic Year 1999-2000] (open access)

[Acceptance of Marcus Fellowship: Academic Year 1999-2000]

A letter from an enthusiastic applicant officially accepting the Marcus Fellowship offer for the academic year 1999-2000.
Date: May 14, 1999
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
Acceptance test procedure MICON software exhaust fan control modifications (open access)

Acceptance test procedure MICON software exhaust fan control modifications

This acceptance test verifies the MICON program changes for the new automatic transfer switch ATS-2 alarms, the Closed Loop Cooling isolator status, the CB-3 position alarm, and the alarms for the new emergency fan damper backup air compressor.
Date: May 21, 1999
Creator: SILVAN, G.R.
Object Type: Report
System: The UNT Digital Library
Acceptance test report MICON software exhaust fan control modifications (open access)

Acceptance test report MICON software exhaust fan control modifications

This report documents the results the acceptance test HNF-4108 which verifies the MICON program changes for the new automatic transfer switch ATS-2 alarms, the Closed Loop Cooling isolator status, the CB-3 position alarm, the alarms for the new emergency fan damper backup air compressor, and the generator sequencer logic.
Date: May 20, 1999
Creator: SILVAN, G.R.
Object Type: Report
System: The UNT Digital Library
Accurately measuring MPI broadcasts in a computational grid (open access)

Accurately measuring MPI broadcasts in a computational grid

An MPI library's implementation of broadcast communication can significantly affect the performance of applications built with that library. In order to choose between similar implementations or to evaluate available libraries, accurate measurements of broadcast performance are required. As we demonstrate, existing methods for measuring broadcast performance are either inaccurate or inadequate. Fortunately, we have designed an accurate method for measuring broadcast performance, even in a challenging grid environment. Measuring broadcast performance is not easy. Simply sending one broadcast after another allows them to proceed through the network concurrently, thus resulting in inaccurate per broadcast timings. Existing methods either fail to eliminate this pipelining effect or eliminate it by introducing overheads that are as difficult to measure as the performance of the broadcast itself. This problem becomes even more challenging in grid environments. Latencies a long different links can vary significantly. Thus, an algorithm's performance is difficult to predict from it's communication pattern. Even when accurate pre-diction is possible, the pattern is often unknown. Our method introduces a measurable overhead to eliminate the pipelining effect, regardless of variations in link latencies. choose between different available implementations. Also, accurate and complete measurements could guide use of a given implementation to improve application …
Date: May 6, 1999
Creator: T, Karonis N & de Supinski, B R
Object Type: Article
System: The UNT Digital Library
An Adaptive Linearization Method for a Constraint Satisfaction Problem in Semiconductor Device Design Optimization (open access)

An Adaptive Linearization Method for a Constraint Satisfaction Problem in Semiconductor Device Design Optimization

The device optimization is a very important element in semiconductor technology advancement. Its objective is to find a design point for a semiconductor device so that the optimized design goal meets all specified constraints. As in other engineering fields, a nonlinear optimizer is often used for design optimization. One major drawback of using a nonlinear optimizer is that it can only partially explore the design space and return a local optimal solution. This dissertation provides an adaptive optimization design methodology to allow the designer to explore the design space and obtain a globally optimal solution. One key element of our method is to quickly compute the set of all feasible solutions, also called the acceptability region. We described a polytope-based representation for the acceptability region and an adaptive linearization technique for device performance model approximation. These efficiency enhancements have enabled significant speed-up in estimating acceptability regions and allow acceptability regions to be estimated for a larger class of device design tasks. Our linearization technique also provides an efficient mechanism to guarantee the global accuracy of the computed acceptability region. To visualize the acceptability region, we study the orthogonal projection of high-dimensional convex polytopes and propose an output sensitive algorithm for …
Date: May 1999
Creator: Chang, Chih-Hui, 1967-
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Adaptive Mesh Refinement in CTH (open access)

Adaptive Mesh Refinement in CTH

This paper reports progress on implementing a new capability of adaptive mesh refinement into the Eulerian multimaterial shock- physics code CTH. The adaptivity is block-based with refinement and unrefinement occurring in an isotropic 2:1 manner. The code is designed to run on serial, multiprocessor and massive parallel platforms. An approximate factor of three in memory and performance improvements over comparable resolution non-adaptive calculations has-been demonstrated for a number of problems.
Date: May 4, 1999
Creator: Crawford, David
Object Type: Article
System: The UNT Digital Library
Addendum to Closure Report for Housekeeping Category Corrective Action Unit 347 Nevada Test Site, Nevada (open access)

Addendum to Closure Report for Housekeeping Category Corrective Action Unit 347 Nevada Test Site, Nevada

None
Date: May 1, 1999
Creator: Parsons, Shannon
Object Type: Report
System: The UNT Digital Library
Addendum to Closure Report for Housekeeping Category Corrective Action Unit 354 Nevada Test Site, Nevada (open access)

Addendum to Closure Report for Housekeeping Category Corrective Action Unit 354 Nevada Test Site, Nevada

None
Date: May 1, 1999
Creator: Parsons, Shannon
Object Type: Report
System: The UNT Digital Library
Addison Transit Center Murals Reflect Historic and Modern Aspects of Township (open access)

Addison Transit Center Murals Reflect Historic and Modern Aspects of Township

News release about the design of DART's Addison Transit Center intended to reflect Addison's history.
Date: May 12, 1999
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Adjustment of Kindergarten Children through Play Sessions Facilitated by Fifth Grade Students Trained in Child-Centered Play Therapy Procedures and Skills (open access)

Adjustment of Kindergarten Children through Play Sessions Facilitated by Fifth Grade Students Trained in Child-Centered Play Therapy Procedures and Skills

This research study investigated the effectiveness of the application of child-centered play therapy procedures and skills by trained fifth grade students in play sessions with kindergarten children who had adjustment difficulties. Specifically, this research determined if play sessions with trained fifth grade students facilitated change in kindergarten children's self concept, internalizing behavior, and externalizing behavior and their parents' stress level.
Date: May 1999
Creator: Baggerly, Jennifer N. (Jennifer Nalini)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Adults With Severe Disabilities: Federal and State Approaches for Personal Care and Other Services (open access)

Adults With Severe Disabilities: Federal and State Approaches for Personal Care and Other Services

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on community-based, long-term care for severely disabled adults, focusing on: (1) the number and characteristics of adults with severe disabilities; (2) the federal assistance available to such individuals; (3) Medicaid coverage of personal care and related services; and (4) how a sample of selected states have implemented Medicaid policies that allow consumers to select their own caregivers, an approach called consumer direction."
Date: May 14, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR (open access)

ADVANCED BYPRODUCT RECOVERY: DIRECT CATALYTIC REDUCTION OF SO2 TO ELEMENTAL SULFUR

Arthur D. Little, Inc., together with its commercialization partner, Engelhard Corporation, and its university partner Tufts, investigated a single-step process for direct, catalytic reduction of sulfur dioxide from regenerable flue gas desulfurization processes to the more valuable elemental sulfur by-product. This development built on recently demonstrated SO{sub 2}-reduction catalyst performance at Tufts University on a DOE-sponsored program and is, in principle, applicable to processing of regenerator off-gases from all regenerable SO{sub 2}-control processes. In this program, laboratory-scale catalyst optimization work at Tufts was combined with supported catalyst formulation work at Engelhard, bench-scale supported catalyst testing at Arthur D. Little and market assessments, also by Arthur D. Little. Objectives included identification and performance evaluation of a catalyst which is robust and flexible with regard to choice of reducing gas. The catalyst formulation was improved significantly over the course of this work owing to the identification of a number of underlying phenomena that tended to reduce catalyst selectivity. The most promising catalysts discovered in the bench-scale tests at Tufts were transformed into monolith-supported catalysts at Engelhard. These catalyst samples were tested at larger scale at Arthur D. Little, where the laboratory-scale results were confirmed, namely that the catalysts do effectively reduce sulfur …
Date: May 1999
Creator: Weber, Robert S.
Object Type: Report
System: The UNT Digital Library