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BRUTE

Description: BRUTE is an algorithm to derive the implied boundary of a piecepart from the part's wireframe representation. BRUTE's input is an IGES file. The geometry is extracted and used to derive the edge-vertex (EV) topology. BRUTE then uses a divide-and-conquer method to derive all reasonable face-edge-vertex (FEV) topologies from the EV topology. The final step is to determine the geometry of each face by using the geometry of its edges. Any FEV topology that contains a face that is not a valid surfac… more
Date: May 1, 1982
Creator: Christensen, N.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FUEL ELEMENT DEVELOPMENT PROGRAM FOR THE PEBBLE BED REACTOR. Final Report

Description: >The basic fuel element consisted of a uniform dispersion of fuel in a 1 1/2 inch diameter graphite sphere. Ceramic coatings for the retention of fission products were studied. It was found-that molecularly deposited'' ceramics such as alumina, siliconized silicon carbide, and pyrolytic carbon were excellent barriers to fission product leakage. The most advantageous location for ceramic coatings was found to be on the individual fuel particles, where the coating was subject to smaller forces an… more
Date: April 30, 1961
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Consolidated fuel-reprocessing program. Progress report, April 1-June 30, 1982

Description: Highlights of progress accomplished during the quarter ending June 30, 1982 are summarized. Discussion is presented under the headings: Process development; Laboratory R and D; Engineering research; Engineering systems; Integrated equipment test facility operation; Instrument development; and HTGR fuel reprocessing.
Date: September 1, 1982
Creator: Burch, W D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of near-surface phenomena and erosion mechanisms in metallic alloys using single- and multi-particle impacts

Description: An experimental study of the effects of material properties on erosion mechanisms was conducted by subjecting targets to single as well as multiple impacts of spherical particles at various velocities. A mechanical properties microprobe was used to monitor the hardening due to the impacts. Initial studies on several engineering alloys showed that work hardening was associated with single impacts, and the results suggested that the capacity to distribute the impact energy over large volumes impr… more
Date: March 1, 1992
Creator: Rao, M. & Keiser, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal plasticity at high heating rates and temperatures

Description: The potential influence of gas bubbles on the viscosity of molten coal at elevated temperatures was estimated by calculations, using literature models for the viscosity of two and three phase suspensions. In one approach, gas bubbles in molten coal were approximated as the dispersed phase of deformable liquid globules in G.I. Taylor's model of emulsion viscosity. This model was incorporated into different models for the viscosity of solid-in-liquid suspensions, in which the dispersed solids are… more
Date: May 1, 1992
Creator: Gerjarusak, S.; Peters, W.A. & Howard, J.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Data testing results for the ENDF/B-V Evaluated Neutron Data File. [20 spheres pulsed with 14-Mev neutrons]

Description: The ENDF/B-V Evaluated Neutron Data File has been tested for validity by comparing calculated and experimental values of k/sub eff/ for 66 critical assemblies and emission neutron spectra for 20 spheres that were pulsed with 14-MeV neutrons. 20 figures, 7 tables.
Date: July 4, 1980
Creator: Howerton, Robert J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface topography measurements over the 1 meter to 10 micrometer spatial period bandwidth

Description: A recently-developed long-trace surface profiling instrument (LTP) is now in operation in our laboratory measuring surface profiles on grazing incidence aspheres and also conventional optical surface. The LTP characterizes surface height profiles in a non-contact manner over spatial periods ranging from 1 meter (the maximum scan length) to 2 mm (the Nyquist period for 1 mm sampling period) and complements the range of our WYKO NCP-1000 2.5X surface roughness profiler (5 mm to 9.8 {mu}m). Using … more
Date: September 1, 1989
Creator: Takacs, P. Z.; Furenlid, K.; DeBiasse, R. A.; Church, E. L. (Brookhaven National Lab., Upton, NY (USA) & Army Research and Development Command, Dover, NJ (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of MOOT to scattering of elastic waves from compound inclusions

Description: It is shown how MOOT (method of optimal truncation, a convergent T-matrix scheme) can be used to calculate elastic wave scattering from compound inclusions, i.e., inclusions which themselves contain flaws - inclusions, voids, or cracks. The general equations are derived, and they are solved for a particular axially-symmetric case - a cracked spherical inclusion immersed in fluid. The crack edge is a circle on the equatorial plane; the crack can extend either inward to the center or outward to t… more
Date: January 1, 1980
Creator: Visscher, W.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Non-intrusive measurement of particle charge: Electrostatic dry coal cleaning

Description: Research continues on a method using electric fields to separate coal and unwanted mineral matter. Simulations using spherical particles made of silica were performed to evaluate the charge measurement capabilities of the apparatus. Particle velocity and relative density data were collected for two different electric field strengths. The resulting velocity and density maps are displayed. A mathematical description of forces experienced by the particle within the apparatus is outlined. (VC)
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Image processing applications in NDE

Description: Nondestructive examination (NDE) can be defined as a technique or collection of techniques that permits one to determine some property of a material or object without damaging the object. There are a large number of such techniques and most of them use visual imaging in one form or another. They vary from holographic interferometry where displacements under stress are measured to the visual inspection of an objects surface to detect cracks after penetrant has been applied. The use of image proc… more
Date: January 1, 1980
Creator: Morris, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Weld evaluation on spherical pressure vessels using holographic interferometry

Description: Waist welds on spherical experimental pressure vessels have been evaluated under pressure using holographic interferometry. A coincident viewing and illumination optical configuration coupled with a parabolic mirror was used so that the entire weld region could be examined with a single hologram. Positioning the pressure vessel at the focal point of the parabolic mirror provides a relatively undistorted 360 degree view of the waist weld. Double exposure and real time holography were used to obt… more
Date: May 14, 1980
Creator: Boyd, D.M. & Wilcox, W.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of finite-element stress analysis with experimental copper sphere impacts. [NONSAP computer code]

Description: Three copper spheres were impacted on targets of varying surface finishes at 100 m/s. Impact face friction was varied for each test and the impact was photographed with a high-speed camera. Postimpact strains and deformation were measured. A finite-element computer code, NONSAP, was used to model the impact. The best agreement between computer prediction and experiment was obtained using isoparametric elements, a graded mesh, and actual high-strain-rate copper stress-strain data. Frictional con… more
Date: July 1, 1980
Creator: Frantz, C. E.; Hecker, S. S.; Stout, M. G. & Browning, R. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quarterly Progress Report: October 1, 1991-December 31, 1991

Description: In this quarter we accomplished two milestones. First, we qualitatively compared the approximate solutions for gravity-driven granular flows down bumpy inclines obtained by Richman and Marciniec (1990) to the experimental results for the same flows obtained by Johnson and Jackson (1990). The comparison was made by employing the reparameterized solutions of Richman and Marciniec (1990) and by analyzing several angles of inclination, coefficients of restitution, and boundary geometries. Next, we … more
Date: January 1, 1991
Creator: Richman, M.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computer modeling of gas flow and gas loading of rock in a bench blasting environment

Description: Numerical modeling can contribute greatly to an understanding of the physics involved in the blasting process. This paper will describe the latest enhancements to the blast modeling code DMC (Distinct Motion Code) (Taylor and Preece, 1989) and will demonstrate the ability of DMC to model gas flow and rock motion in a bench blasting environment. DMC has been used previously to model rock motion associated with blasting in a cratering environment (Preece and Taylor, 1990) and in confined volume b… more
Date: January 1, 1991
Creator: Preece, D.S.; Baer, M.R. (Sandia National Labs., Albuquerque, NM (United States)) & Knudsen, S.D. (RE/SPEC, Inc., Albuquerque, NM (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of spherical surfaces

Description: The surface geometry of a spherical object is often incompletely evaluated because of limitations inherent in the techniques used to measure it. If several techniques measuring different aspects of the surface are combined, a more complete description can be optained.
Date: January 1, 1982
Creator: Gauler, A. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Kinetic Theory and Boundary Conditions for Flows of Highly Inelastic Spheres

Description: Our second quarter milestone was to reparameterize the solutions obtained by Richman and Marciniec (J. Appl. Mech., Vol. 57, No. 4, pp. 1036--1043, 1990) for steady, fully developed, gravity-driven, granular flows down bumpy inclines. The purpose of the reparameterization was to follow the results presented by Johnson, et. al. (J. Fluid. Mech., Vol. 210, pp. 501--535, 1990) by predicting the dependence of mass flow rate on mass hold-up. With this dependence established, it would be possible to … more
Date: January 1, 1991
Creator: Richman, M. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Integrated system for production of neutronics and photonics calculational constants. Volume 15, Part E. Data testing results for the LLL Evaluated Nuclear Data Library (ENDL-78)

Description: The LLL Evaluated Nuclear Data Library (ENDL-78) was tested for validity by comparing calculated and experimental values of k/sub eff/ for 67 critical assemblies and emission neutron spectra for 22 spheres that were pulsed with 14-MeV neutrons. 22 figures, 5 tables.
Date: August 13, 1979
Creator: Howerton, Robert J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A study of coal particle shape and three-body wear: Part 1, Design and development of a new three-body wear testing machine: Part 2, Particle shape and three-body wear

Description: Three-body wear involves two surfaces and an intermediate particle trapped between the two surfaces. A machine has been constructed to measure normal and frictional forces due to three-body wear. This machine accurately positions specimens a predetermined distance apart from each other and introduces particles to the interface between the specimens. Different types of specimen combinations have been tested to give a variety of data. Loads that result from the wear test are sampled and stored. W… more
Date: January 1, 1991
Creator: Clark, N.N.; Means, K.H.; James, R. & Thompson, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of laser ultrasonic measurements of surface waves on elastic spheres

Description: In conventional ultrasonic nondestructive evaluation studies, piezoelectric transducers are used to generate sound waves in solids via a couplant that transmits the mechanical motions. In recent years, a different method of generating sound in solids, pulsed laser heating, was introduced by White. This method is noncontacting, requires no coupling medium, and operates directly on the surface of the specimen. Noncontacting ultrasonic detection using laser interferometers of several types has als… more
Date: January 1, 1991
Creator: Koo, L.S. & Telschow, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Morphology of rubber modified epoxy encapsulants

Description: Examination of rubber modified epoxy, cured with diethanol amine, via the transmission electron microscope has shown that a broad distribution of rubber particle sizes exists. The average particle size for particles greater than .1 ..mu..m was found to be .8 ..mu..m. A significant population of particles was found whose diameters are less than .1 ..mu..m. Examination of the particle interface showed that the interface between the dispersed phase and the epoxy matrix was sharp within the accurac… more
Date: January 1, 1979
Creator: Sayre, J.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(Particulate Flow Research Lab) quarterly progress report, July 1, 1991--September 30, 1991

Description: Research at the Particulate Flow Research Lab continued. In the previous report it was mentioned that an anticipated change in the sphere diameter necessitated a resizing of the chute components. A check has indicated that the increased size has added enough weight to require a re-evaluation of the stresses requiring stronger fasteners. Mathematical formalism is given for the chip radiation model, and signal processing of the radiation received from the transmitting chips has been improved. A p… more
Date: October 15, 1991
Creator: Rosato, A. D.; Dave, R. N.; Fischer, I. S. & Carr, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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