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1-10 Mbar Laser-Driven Shocks Using the Janus Laser Facility

Description: We report preliminary results using the Lawrence Livermore National Laboratory (LLNL) Janus laser facility to generate high pressure laser-driven shocks in the 1-10 Mbar regime. These experiments address various issues, including shock steadiness, planarity, uniformity and low target preheat, important for making precision EOS measurements on a small (E < 250 J) laser facility. A brief description of the experimental techniques, target design and measurements will be given.
Date: August 10, 2001
Creator: Dunn, J.; Price, D. F.; Moon, S. J.; Cauble, R. C.; Springer, P. T. & Ng, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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1-D closure models for slender 3-D viscoelastic free jets: von Karman flow geometry and elliptical cross section

Description: In this paper we derive one space dimensional, reduced systems of equations (1-D closure models) for viscoelastic free jets. We begin with the three-dimensional system of conservation laws and a Maxwell-Jeffreys constitutive law for an incompressible viscoelastic fluid. First, we exhibit exact truncations to a finite, closed system of 1-D equations based on classical velocity assumptions of von Karman. Next, we demonstrate that the 3-D free surface boundary conditions overconstrain these trunca… more
Date: January 1, 1988
Creator: Bechtel, S. E.; Forest, M. G.; Holm, D. D. & Lin, K. J.
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Partner: UNT Libraries Government Documents Department
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1-D Equilibrium Discrete Diffusion Monte Carlo

Description: We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-e… more
Date: August 2000
Creator: Evans, T. M.; Urbatsch, T. J. & Lichtenstein, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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S-1 project. Volume I. Architecture. 1979 annual report

Description: The US Navy is one of the world's largest users of digital computing equipment having a procurement cost of at least $50,000, and is the single largest such computer customer in the Department of Defense. Its projected acquisition plan for embedded computer systems during the first half of the 80s contemplates the installation of over 10,000 such systems at an estimated cost of several billions of dollars. This expenditure, though large, is dwarfed by the 85 billion dollars which DOD is project… more
Date: January 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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S-1 project. Volume II. Hardware. 1979 annual report

Description: This volume includes highlights of the design of the Mark IIA uniprocessor (SMI-2), and the SCALD II user's manual. SCALD (structured computer-aided logic design system) cuts the cost and time required to design logic by letting the logic designer express ideas as naturally as possible, and by eliminating as many errors as possible - through consistency checking, simulation, and timing verification - before the hardware is built. (GHT)
Date: January 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A 2.14 ms candidate optical pulsar in SN1987A: Ten years after

Description: We have monitored Supernova 1987A in optical/near-infrared bands from a few weeks following its birth until the present time in order to search for a pulsar remnant. We have found an apparent pattern of emission near the frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14 ms period on numerous occasions over the next four y… more
Date: September 1, 1997
Creator: Middleditch, J.; Kristian, J. A.; Kunkel, W. E.; Hill, K. M. & Watson, R. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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2-D Finite Element Cable and Box IEMP Analysis

Description: A 2-D finite element code has been developed for the solution of arbitrary geometry cable SGEMP and box IEMP problems. The quasi- static electric field equations with radiation- induced charge deposition and radiation-induced conductivity y are numerically solved on a triangular mesh. Multiple regions of different dielectric materials and multiple conductors are permitted.
Date: December 17, 1998
Creator: Scivner, G.J. & Turner, C.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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2-D image segmentation using minimum spanning trees

Description: This paper presents a new algorithm for partitioning a gray-level image into connected homogeneous regions. The novelty of this algorithm lies in the fact that by constructing a minimum spanning tree representation of a gray-level image, it reduces a region partitioning problem to a minimum spanning tree partitioning problem, and hence reduces the computational complexity of the region partitioning problem. The tree-partitioning algorithm, in essence, partitions a minimum spanning tree into sub… more
Date: September 1995
Creator: Xu, Y. & Uberbacher, E. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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N = 2 Maxwell-Einstein Supergravity Theories: Their Compact and Non-Compact Gaugings and Jordan Algebras

Description: In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is… more
Date: January 1, 1985
Creator: Guenaydin, M.; Sierra, G. & Townsend, P.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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2 x 2 Polyethylene Reflected and Moderated Highly Enriched Uranium System with Rhenium

Description: The 2 × 2 array HEU-Re experiment was performed on the Planet universal critical assembly machine on November 4th, 2003 at the Los Alamos Critical Experiments Facility (LACEF) at Los Alamos National Laboratory (LANL). For this experiment, there were 10 ½ units, each full unit containing four HEU foils and two rhenium foils. The top unit contained only two HEU foils and two rhenium foils. A total of 42 HEU foils were used for this experiment. Rhenium is a desirable cladding material for space nu… more
Date: September 1, 2010
Creator: Ellis, A. Nichole; Hutchinson, Jesson; Bess, John D.; Polyakov, Dmitry N.; Glushkov, Evgeny S. & Glushkov, Alexey E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A 3-D adaptive mesh refinement algorithm for multimaterial gas dynamics

Description: Adaptive Mesh Refinement (AMR) in conjunction with high order upwind finite difference methods has been used effectively on a variety of problems. In this paper we discuss an implementation of an AMR finite difference method that solves the equations of gas dynamics with two material species in three dimensions. An equation for the evolution of volume fractions augments the gas dynamics system. The material interface is preserved and tracked from the volume fractions using a piecewise linear re… more
Date: August 12, 1991
Creator: Puckett, E. G. & Saltzman, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D Experimental Fracture Analysis at High Temperature

Description: T*e, which is an elastic-plastic fracture parameter based on incremental theory of plasticity, was determined numerically and experimentally. The T*e integral of a tunneling crack in 2024-T3 aluminum, three point bend specimen was obtained through a hybrid analysis of moire interferometry and 3-D elastic-plastic finite element analysis. The results were verified by the good agreement between the experimentally and numerically determined T*e on the specimen surface.
Date: September 14, 2001
Creator: Jackson, John H. & Kobayashi, Albert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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3-D field computation: The near-triumph of commerical codes

Description: In recent years, more and more of those who design and analyze magnets and other devices are using commercial codes rather than developing their own. This paper considers the commercial codes and the features available with them. Other recent trends with 3-D field computation include parallel computation and visualization methods such as virtual reality systems.
Date: July 1995
Creator: Turner, L. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D Field Computations for Accelerator Magnets Using Finite Element and Integral Codes

Description: Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960's, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of … more
Date: 1992~
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D field computations for accelerator magnets using finite element and integral codes

Description: Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960`s, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of … more
Date: December 1, 1992
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D Finite Element Analysis of Induction Logging in a Dipping Formation

Description: Electromagnetic induction by a magnetic dipole located above a dipping interface is of relevance to the petroleum well-logging industry. The problem is fully three-dimensional (3-D) when formulated as above, but reduces to an analytically tractable one-dimensional (1-D) problem when cast as a small tilted coil above a horizontal interface. The two problems are related by a simple coordinate rotation. An examination of the induced eddy currents and the electric charge accumulation at the interfa… more
Date: July 20, 2000
Creator: Everett, Mark E.; Badea, Eugene A,; Shen, Liang, C.; Merchant, Gulamabbas A. & Weiss, Chester J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-d finite element model development for biomechanics: a software demonstration

Description: Finite element analysis is becoming an increasingly important part of biomechanics and orthopedic research, as computational resources become more powerful, and data handling algorithms become more sophisticated. Until recently, tools with sufficient power did not exist or were not accessible to adequately model complicated, three-dimensional, nonlinear biomechanical systems. In the past, finite element analyses in biomechanics have often been limited to two-dimensional approaches, linear analy… more
Date: March 1, 1997
Creator: Hollerbach, K.; Hollister, A.M. & Ashby, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

Description: A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predict… more
Date: January 1, 1989
Creator: Elias, E.; Kaizermann, S.; Perry, R. B. & Fiarman, S.
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Partner: UNT Libraries Government Documents Department
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3-D hybrid PIC code to model the tilt mode in FRCs

Description: The results from QN3D are presented. QN3D is a 3-dimensional hybrid particle-in-cell code designed to run efficiently on the Cray-2 Multiprocessor. The chief application has been to the tilt mode instability in FRCs. QN3D accepts as input, the magnetic field, the ion particle density and the ion temperature on a two-dimensional r-z grid. These quantities are interpolated to the rest of the cartesian grid under the assumption of azimuthal symmetry. The particles are initialized with random numbe… more
Date: June 1, 1987
Creator: Horowitz, E. J. & Shumaker, D. E.
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Partner: UNT Libraries Government Documents Department
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A 3-D measurement system using object-oriented FORTH

Description: Discussed is a system for storing 3-D measurements of points that relates the coordinate system of the measurement device to the global coordinate system. The program described here used object-oriented FORTH to store the measured points as sons of the measuring device location. Conversion of local coordinates to absolute coordinates is performed by passing messages to the point objects. Modifications to the object-oriented FORTH system are also described. 1 ref.
Date: January 1, 1989
Creator: Butterfield, K.B.
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Partner: UNT Libraries Government Documents Department
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A 3-D Model of Signaling and Transport Pathways in Epithelial Cells

Description: A 3-dimensional computer model was developed to simulate the spatial and chemical evolution of calcium ions inside an array of human epithelial kidney cells. This is a prototype model, intended to develop a methodology to incorporate much more complex interactions of metabolic and other processes within many types of cells and lead to increased ability to predict cellular responses to disease as well as to chemical and biological warfare situations. Preliminary tests of the model are described.
Date: April 1, 2005
Creator: Quong, Andrew A. & Westbrook, Charles K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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