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Neutron scattering analysis with microscopic optical model potentials

Description: A review of microscopic optical model potentials used in the analysis of neutron scattering and analyzing power data below 100 MeV (5 {le}E{sub n}{le}100 MeV) is presented. The quality of the fits to the data over a wide massd ({sup 6}Li-{sup 239}Pu) and energy range is discussed. It is shown that reasonably good agreement with the data is obtained with only three parameters, {lambda}{sub V}, {lambda}{sub W}, and {lambda}{sub SO}, which show a smooth mass and energy dependence. These parameters… more
Date: September 3, 1991
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
open access

Shielding requirements for the transport of nuclear warhead components under decommissioning

Description: The requirements to carry out accurate shielding calculations involved with the safe off-site transportation of packages containing nuclear warhead components, special assemblies and radioactive materials are discussed. The need for (a) detailed information on the geometry and material composition of the packaging and radioactive load, (b) accurate representation of the differential energy spectra (dN/dE) for the neutron and gamma spectra emitted by the radioactive materials enclosed in the pac… more
Date: September 1, 1994
Creator: Hansen, L. F.
Partner: UNT Libraries Government Documents Department
open access

Key Geomechanics Issues at the Waste Isolation Pilot Plant Geomechanics

Description: Mechanical and hydrological properties of rock salt provide excellent bases for geological isolation of hazardous materials. Regulatory compliance determinations for the Waste Isolation Pilot Plant (WIPP) stand as testament to the widely held conclusion that salt provides excellent isolation properties. The WIPP saga began in the 1950s when the U.S. National Academy of Sciences (NAS) recommended a salt vault as a promising solution to the national problem of nuclear waste disposal. For over 20 … more
Date: September 1, 1999
Creator: Hansen, Francis D.
Partner: UNT Libraries Government Documents Department
open access

Geometric optimization

Description: An algorithm is presented which describes an application independent method for reducing the number of polygonal primitives required to faithfully represent an object. Reducing polygon count without a corresponding reduction in object detail is important for: achieving interactive frame rates in scientific visualization, reducing mass storage requirements, and facilitating the transmission of large, multi-timestep geometric data sets. This paper shows how coplanar and nearly coplanar polygons c… more
Date: September 1, 1993
Creator: Hinker, P. & Hansen, C.
Partner: UNT Libraries Government Documents Department
open access

An evaluation of the B&W Owners Group BAW-10182 topical report: Justification for increasing the engineered safety features actuation system on-line test intervals. Technical evaluation report

Description: This Technical Evaluation Report provides an evaluation of the Babcock and Wilcox Owners Group (B&WOG) Technical Specifications Committee Topical Report BAW-10182, entitled, ``Justification for Increasing Engineered Safety Features Actuation System (ESFAS) On-Line Test Intervals.`` This evaluation was performed by the Idaho National Engineering Laboratory in support of the Nuclear Regulatory Commission. The BAW-10182 report presents justification for the extension of on-line test intervals from… more
Date: September 1, 1993
Creator: Smith, C. L. & Hansen, J. L.
Partner: UNT Libraries Government Documents Department
open access

Visualization on massively parallel computers using CM/AVS

Description: CM/AVS is a visualization environment for the massively parallel CM-5 from Thinking Machines. It provides a backend to the standard commercially available AVS visualization product. At the Advanced Computing Laboratory at Los Alamos National Laboratory, we have been experimenting and utilizing this software within our visualization environment. This paper describes our experiences with CM/AVS. The conclusions reached are applicable to any implimentation of visualization software within a massiv… more
Date: September 1, 1993
Creator: Krogh, M. F. & Hansen, C. D.
Partner: UNT Libraries Government Documents Department
open access

Fast data parallel polygon rendering

Description: This paper describes a parallel method for polygonal rendering on a massively parallel SIMD machine. This method, based on a simple shading model, is targeted for applications which require very fast polygon rendering for extremely large sets of polygons such as is found in many scientific visualization applications. The algorithms described in this paper are incorporated into a library of 3D graphics routines written for the Connection Machine. The routines are implemented on both the CM-200 a… more
Date: September 1, 1993
Creator: Ortega, F. A. & Hansen, C. D.
Partner: UNT Libraries Government Documents Department
open access

Technology status report: In situ vitrification applied to buried wastes

Description: This document is a technical status report on In Situ Vitrification (ISV) as applied to buried waste; the report takes both technical and institutional concerns into perspective. The ISV process involves electrically melting such contaminated solid media as soil, sediment, sludge, and mill tailings. The resultant product is a high-quality glass-and-crystalline waste form that possesses high resistance to corrosion and leaching and is capable of long-term environmental exposure without significa… more
Date: September 1, 1992
Creator: Thompson, L. E.; Bates, S. O. & Hansen, J. E.
Partner: UNT Libraries Government Documents Department
open access

Extrinsic germanium photoconductors for far-IR astronomy: Research results and works in progress

Description: The authors report on Ge:Ga and Ge:Sb photoconductor materials and detectors that are under development. The best unstressed Ge:Ga devices exhibit dark currents lower than 200 electrons per second with a concurrent responsivity of 2 A/W and detective quantum efficiency (DQE) of 5%. For higher backgrounds an operating temperature of 3 K can be used. This increases the DQE to 7% and the responsivity to 4.5 A/W. The figures of merit are roughly the same for stressed Ge:Ga operated at 1.5 K and 2 K… more
Date: September 1, 1996
Creator: Beeman, J. W.; Hansen, W. L. & Haller, E. E.
Partner: UNT Libraries Government Documents Department
open access

ACLMPL: Portable and efficient message passing for MPPs

Description: This paper presents the Advanced Computing Lab Message Passing Library (ACLMPL). Modeled after Thinking Machines Corporation`s CMMD, ACLMPL is a high throughout, low latency communications library for building message passing applications. The library has been implemented on the Cray T3D, Thinking Machines CM-5, SGI workstations, and on top of PVM. On the Cray T3D, benchmarks show ACLMPL to be 4 to 7 times faster than MPI or PVM.
Date: September 19, 1995
Creator: Painter, J.; Krogh, M.; Hansen, C.; McCormick, P. & de Verdiere, G.C.
Partner: UNT Libraries Government Documents Department
open access

The ACL Message Passing Library

Description: This paper presents the ACL (Advanced Computing Lab) Message Passing Library. It is a high throughput, low latency communications library, based on Thinking Machines Corp.`s CMMD, upon which message passing applications can be built. The library has been implemented on the Cray T3D, Thinking Machines CM-5, SGI workstations, and on top of PVM.
Date: September 1, 1995
Creator: Painter, J.; McCormick, P.; Krogh, M.; Hansen, C. & Colin de Verdiere, G.
Partner: UNT Libraries Government Documents Department
open access

Photovoltaic module performance and durability following long-term field exposure

Description: Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial mod… more
Date: September 8, 1998
Creator: Ellibee, D. E.; Hansen, B. R.; King, D. L.; Kratochvil, J. A. & Quintana, M. A.
Partner: UNT Libraries Government Documents Department
open access

Three-color resonance ionization spectroscopy of Zr in Si

Description: It has been proposed that the composition of the solar wind could be measured directly by transporting ultrapure collectors into space, exposing them to the solar wind, and returning them to earth for analysis. In a study to help assess the applicability of present and future postionization secondary neutral mass spectrometers for measuring solar wind implanted samples, measurements of Zr in Si were performed. A three-color resonant ionization scheme proved to be efficient while producing a bac… more
Date: September 1, 1996
Creator: Hansen, C. S.; Calaway, W. F.; Pellin, M. J.; Wiens, R. C. & Burnett, D. S.
Partner: UNT Libraries Government Documents Department
open access

A two-fold reduction in measurement time for neutron assay: Initial tests of a prototype dual-gated shift register

Description: Neutron coincidence counting (NCC) is used routinely around the world for nondestructive mass assay of uranium and plutonium in many forms, including waste. Compared with other methods, NCC is generally the most flexible, economic, and rapid. Many applications of NCC would benefit from a reduction in counting time required for a fixed random error. We have developed and tested the first prototype of a dual- gated, shift-register-based electronics unit that offers the potential of decreased meas… more
Date: September 1, 1996
Creator: Stewart, J.E.; Bourret, S.C.; Krick, M.S.; Hansen, W.J. & Harker, W.C.
Partner: UNT Libraries Government Documents Department
open access

Hot blast stove process model and model-based controller

Description: This paper describes the process model and model-based control techniques implemented on the hot blast stoves for the No. 7 Blast Furnace at the Inland Steel facility in East Chicago, Indiana. A detailed heat transfer model of the stoves is developed and verified using plant data. This model is used as part of a predictive control scheme to determine the minimum amount of fuel necessary to achieve the blast air requirements. The model is also used to predict maximum and minimum temperature cons… more
Date: September 1998
Creator: Muske, K. R.; Howse, J. W.; Hansen, G. A.; Cagliostro, D. J. & Chaubal, P. C.
Partner: UNT Libraries Government Documents Department
open access

Long Range Neutron Detection: A Progress Report

Description: The detection of neutron sources horn a considerable distance constitutes a problem that must be treated separately from the bulk of other neutron-detection applications. This report analyzes this problem, describes a number of possible approaches, and describes the design and construction of a square-meter detection system using the approach of moderator-free directional neutron detection. Although experimental results are not the focus of this report a few preliminary results are offered in t… more
Date: September 18, 1998
Creator: Peurrung, A. J.; Kunz, C. L.; Stromswold, D. C.; Reeder, P. L. & Hansen, R. R.
Partner: UNT Libraries Government Documents Department
open access

Intrinsic signatures of polymer based fiber reinforced composite structures: An ultrasonic approach

Description: Combination of ultrasound, image comparison, and statistical analysis provide a method for acquiring a subsurface, intrinsic signature from polymer based, fiber-reinforced composites. Although materials properties are carefully controlled, localized fluctuations in the macrostructure and microstructure permit a basis for ultrasound and other NDE methods to read intrinsic signatures from a material. Under ideal conditions where a material signature is stable and has sufficient spatial features a… more
Date: September 1, 1993
Creator: Good, M. S.; Hansen, N. H.; Heasler, P. G.; Undem, H. A.; Fuller, J. L. & Skorpik, J. R.
Partner: UNT Libraries Government Documents Department
open access

Decision Analysis for Mobilizing and Retrieving Sludge From Double-Shell Tanks

Description: This decision analysis evaluates alternative technologies for the initial mobilization and retrieval of sludges in double-shell tanks (DSTs). The analysis is from the perspective of the need to move sludges from one DST to another for interim retrieval. It supports the more general decision of which technologies to use to retreive various types of DST waste. The initial analysis is from the perspective of a typical DST with 2 ft of sludge to mobilize. During the course of the analysis, it becam… more
Date: September 1, 1997
Creator: Brothers, A. J.; Williams, N. C.; Dukelow, J. S.; Hansen, R. I.; Claghorn, R. D.; Grenard, C. E. et al.
Partner: UNT Libraries Government Documents Department
open access

Technology status report: In situ vitrification applied to buried wastes

Description: This document is a technical status report on In Situ Vitrification (ISV) as applied to buried waste; the report takes both technical and institutional concerns into perspective. The ISV process involves electrically melting such contaminated solid media as soil, sediment, sludge, and mill tailings. The resultant product is a high-quality glass-and-crystalline waste form that possesses high resistance to corrosion and leaching and is capable of long-term environmental exposure without significa… more
Date: September 1, 1992
Creator: Thompson, L.E. (Pacific Northwest Lab., Richland, WA (United States)); Bates, S.O. (EG and G Idaho, Inc., Idaho Falls, ID (United States)) & Hansen, J.E. (Geosafe Corp., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department
open access

Procedures for Determining the Performance of Stand-Alone Photovoltaic Systems

Description: This document provides the procedures for determining the performance of stand-alone PV systems. The procedures in this document provide a common approach for evaluating whether a given PV system is suitable to perform the function for which it was designed and manufactured to accomplish, and whether it will provide adequate power to run the load. These procedures cover small stand-alone PV systems. They cover complete outdoor system testing. Test results are valid only for the system that is t… more
Date: September 21, 1999
Creator: McNutt, P.; Kroposki, B.; Hansen, R.; DeBlasio, R. (National Renewable Energy Laboratory); Thomas, M. (Sandia National Laboratories); Durand, S. (Florida Solar Energy Center) et al.
Partner: UNT Libraries Government Documents Department
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