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Generalized b-spline subdivision-surface wavelets and lossless compression

Description: We present a new construction of wavelets on arbitrary two-manifold topology for geometry compression. The constructed wavelets generalize symmetric tensor product wavelets with associated B-spline scaling functions to irregular polygonal base mesh domains. The wavelets and scaling functions are tensor products almost everywhere, except in the neighborhoods of some extraordinary points (points of valence unequal four) in the base mesh that defines the topology. The compression of arbitrary poly… more
Date: November 24, 1999
Creator: Bertram, M; Duchaineau, M A; Hamann, B & Joy, K I
Partner: UNT Libraries Government Documents Department
open access

Thermal Fusing Model of Conducting Particle Composites

Description: Composites of carbon black particles in polyethylene are known to exhibit an unusually rapid increase in resistivity as the applied field is increased, making this material useful in automatically resettable fuses. In this application the composite is in series with the circuit it is protecting: at low applied voltages this circuit is the load, but at high applied voltages the composite becomes the load, limiting the current to the circuit. We present a simple model of this behavior in terms of… more
Date: June 24, 1999
Creator: Martin, James E.
Partner: UNT Libraries Government Documents Department
open access

FANTM: The First Article NIF Test Module for the Laser Power Conditioning System

Description: Designing and developing the 1.7 to 2. 1-MJ Power Conditioning System (PCS) that powers the flashlamps for the National Ignition Facility (NIF), currently being constructed at Lawrence Livermore National Labs (LLNL), is one of several responsibilities assumed by Sandia National Labs (SNL) in support of the NIF Project. The test facility that has evolved over the last three years to satisfy the project requirements is called FANTM. It was built at SNL and has operated for about 17,000 shots to d… more
Date: June 24, 1999
Creator: Hammon, Jud; Harjes, Henry C.; Moore, William B.S.; Smith, David L. & Wilson, J. Michael
Partner: UNT Libraries Government Documents Department
open access

Final state interaction phase in B decays

Description: From an estimate of the meson-meson inelastic scattering at 5 GeV it is concluded that a typical strong phase in B decays to two mesons is of order of 20{sup o}. For a particular final state an estimate of the phase depends on whether that state is more or less probable as a final state compared to those states to which it is connected by the strong interaction S matrix.
Date: March 24, 1999
Creator: Suzuki, Mahiko & Wolfenstein, Lincoln
Partner: UNT Libraries Government Documents Department
open access

Anisotropic Magnetism in Field-Structured Composites

Description: Magnetic field-structured-composites (FSCs) are made by structuring magnetic particle suspensions in uniaxial or biaxial (e.g. rotating) magnetic fields, while polymerizing the suspending resin. A uniaxial field produces chain-like particle structures, and a biaxial field produces sheet-like particle structures. In either case, these anisotropic structures affect the measured magnetic hysteresis loops, with the magnetic remanence and susceptibility increased significantly along the axis of the … more
Date: June 24, 1999
Creator: Anderson, Robert A.; Martin, James E.; Odinek, Judy & Venturini, Eugene
Partner: UNT Libraries Government Documents Department
open access

Performance Characteristics of an Extended Throat Flow Nozzle for the Measurement of High Void Fraction Multi-Phase Flows

Description: An extended throat flow nozzle has been examined as a device for the measurement of very high void fraction multi-phase flows. Due to its greater density and partial contact with the wall, the equilibrium velocity of the liquid phase appreciably lags that of the lighter gas phase. The two phases are strongly coupled resulting in pressure drops across the contraction and in the extended throat that are significantly different than those experienced in single-phase flow. Information about the mas… more
Date: March 24, 1999
Creator: Fincke, James R. (INEEL), Ronnenkamp, C.; Kruse, D.; Krogue, J. & Householder, D. (Perry Equipment Corporation)
Partner: UNT Libraries Government Documents Department
open access

Transformation Mechanism and Kinetics for the Pressure-Induced Phase Transition in Shocked CdS

Description: The pressure-induced phase transition in CdS was investigated using picosecond time-resolved electronic spectroscopy in plate impact shock wave experiments. Real-time changes in the electronic spectra were observed, with 100 ps time resolution, in single crystals of CdS shocked along the c and a axes to peak stresses between 35 and 90 kbar (above the phase transition stress of approximately 30 kbar measured in continuum studies). When shocked to stresses above approximately 50 kbar along the cr… more
Date: June 24, 1999
Creator: Gupta, Y.M.; Knudson, M.D. & Kunz, A.B.
Partner: UNT Libraries Government Documents Department
open access

NRC-BNL Benchmark Program on Evaluation of Methods for Seismic Analysis of Coupled Systems

Description: A NRC-BNL benchmark program for evaluation of state-of-the-art analysis methods and computer programs for seismic analysis of coupled structures with non-classical damping is described. The program includes a series of benchmarking problems designed to investigate various aspects of complexities, applications and limitations associated with methods for analysis of non-classically damped structures. Discussions are provided on the benchmarking process, benchmark structural models, and the evalua… more
Date: March 24, 1999
Creator: Chokshi, N.; DeGrassi, G. & Xu, J.
Partner: UNT Libraries Government Documents Department
open access

Nonlinear harmonic generation and proposed experimental verification in SASE FELs.

Description: Recently, a 3D, polychromatic, nonlinear simulation code was developed to study the growth of nonlinear harmonics in self-amplified spontaneous emission (SASE) free-electron lasers (FELs). The simulation was applied to the parameters for each stage of the Advanced Photon Source (APS) SASE FEL, intended for operation in the visible, UV, and short UV wavelength regimes, respectively, to study the presence of nonlinear harmonic generation. Significant nonlinear harmonic growth is seen. Here, a dis… more
Date: August 24, 1999
Creator: Biedron, S. G.; Freund, H. P. & Milton, S. V.
Partner: UNT Libraries Government Documents Department
open access

Decay out of the yrast superdeformed band in {sup 191}Hg.

Description: The excitation energies and spins of the yrast superdeformed band in {sup 191}Hg have been determined by analyzing the quasicontinuum spectrum connecting the superdeformed and normal-deformed states. The results from this analysis, combined with that given by one-step decay lines, give confident assignments of the spins and energies of the yrast superdeformed band in {sup 191}Hg.
Date: March 24, 1999
Creator: Sien, S.; Reiter, P.; Khoo, T.; Lauritsen, T.; Carpenter, M. P.; Ahmad, I. et al.
Partner: UNT Libraries Government Documents Department
open access

Material accountancy measurement techniques in dry-powdered processing of nuclear spent fuels.

Description: The paper addresses the development of inductively coupled plasma-mass spectrometry (ICPMS), thermal ionization-mass spectrometry (TIMS), alpha-spectrometry, and gamma spectrometry techniques for in-line analysis of highly irradiated (18 to 64 GWD/T) PWR spent fuels in a dry-powdered processing cycle. The dry-powdered technique for direct elemental and isotopic accountancy assay measurements was implemented without the need for separation of the plutonium, uranium and fission product elements i… more
Date: March 24, 1999
Creator: Wolf, S. F.
Partner: UNT Libraries Government Documents Department
open access

Advanced millimeter wave chemical sensor.

Description: This paper discusses the development of an advanced millimeter-wave (mm-wave) chemical sensor and its applications for environmental monitoring and arms control treaty verification. The purpose of this work is to investigate the use of fingerprint-type molecular rotational signatures in the mm-wave spectrum to sense airborne chemicals. The mm-wave spectrum to sense airborne chemicals. The mm-wave sensor, operating in the frequency range of 220-300 GHz, can work under all weather conditions and … more
Date: March 24, 1999
Creator: Gopalsami, N.
Partner: UNT Libraries Government Documents Department
open access

Fuzzy Logic Connectivity in Semiconductor Defect Clustering

Description: In joining defects on semiconductor wafer maps into clusters, it is common for defects caused by different sources to overlap. Simple morphological image processing tends to either join too many unrelated defects together or not enough together. Expert semiconductor fabrication engineers have demonstrated that they can easily group clusters of defects from a common manufacturing problem source into a single signature. Capturing this thought process is ideally suited for fuzzy logic. A system of… more
Date: January 24, 1999
Creator: Gleason, S.S.; Kamowski, T.P. & Tobin, K.W.
Partner: UNT Libraries Government Documents Department
open access

Ceramic Processing

Description: Ceramics represent a unique class of materials that are distinguished from common metals and plastics by their: (1) high hardness, stiffness, and good wear properties (i.e., abrasion resistance); (2) ability to withstand high temperatures (i.e., refractoriness); (3) chemical durability; and (4) electrical properties that allow them to be electrical insulators, semiconductors, or ionic conductors. Ceramics can be broken down into two general categories, traditional and advanced ceramics. Traditi… more
Date: November 24, 1999
Creator: EWSUK,KEVIN G.
Partner: UNT Libraries Government Documents Department
open access

Lifetime measurements and dipole transition rates for superdeformed states in {sup 190}Hg.

Description: The Doppler-shift attenuation method was used to measure life-times of superdeformed (SD) states for both the yrast and the first excited superdeformed band of {sup 190}Hg. Intrinsic quadruple moments Q{sub 0} were extracted. For the first time, the dipole transition rates have been extracted for the inter-band transitions which connect the excited SD band to the yrast states in the second minimum. The results support the interpretation of the excited SD band as a rotational band built on an oc… more
Date: March 24, 1999
Creator: Amro, H.
Partner: UNT Libraries Government Documents Department
open access

Newton-Krylov-Schwarz methods for aerodynamics problems : compressible and incompressible flows on unstructured grids.

Description: We review and extend to the compressible regime an earlier parallelization of an implicit incompressible unstructured Euler code [9], and solve for flow over an M6 wing in subsonic, transonic, and supersonic regimes. While the parallelization philosophy of the compressible case is identical to the incompressible, we focus here on the nonlinear and linear convergence rates, which vary in different physical regimes, and on comparing the performance of currently important computational platforms. … more
Date: February 24, 1999
Creator: Kaushik, D. K.; Keyes, D. E. & Smith, B. F.
Partner: UNT Libraries Government Documents Department
open access

Modeling Manufacturing Processes to Mitigate Technological Risk

Description: An economic model is a tool for determining the justifiable cost of new sensors and subsystems with respect to value and operation. This process balances the R and D costs against the expense of maintaining current operations and allows for a method to calculate economic indices of performance that can be used as control points in deciding whether to continue development or suspend actions. The model can also be used as an integral part of an overall control loop utilizing real-time process dat… more
Date: October 24, 1999
Creator: Allgood, G. O. & Manges, W. W.
Partner: UNT Libraries Government Documents Department
open access

A model for simulating airflow and pollutant dispersion around buildings

Description: A three-dimensional, numerical mode1 for simulating airflow and pollutant dispersion around buildings is described. The model is based on an innovative finite element approach and fully implicit time integration techniques. Linear and nonlinear eddy viscosity/diffusivity submodels are provided for turbulence parameterization. Mode1 predictions for the flow-field and dispersion patterns around a surface-mounted cube are compared with measured data from laboratory experiments.
Date: February 24, 1999
Creator: Chan, S T & Lee, R L
Partner: UNT Libraries Government Documents Department
open access

Corrosion Issues in Solder Joint Design and Service

Description: Corrosion is an important consideration in the design of a solder joint. It must be addressed with respect to the service environment or, as in the case of soldered conduit, as the nature of the medium being transported within piping or tubing. Galvanic-assisted corrosion is of particular concern, given the fact that solder joints are comprised of different metals or alloy compositions that are in contact with one-another. The (thermodynamic) potential for corrosion to take place in a particula… more
Date: November 24, 1999
Creator: VIANCO,PAUL T.
Partner: UNT Libraries Government Documents Department
open access

An advanced ISOL facility based on ATLAS.

Description: The Argonne concept for an accelerator complex for efficiently producing high-quality radioactive beams from ion source energy up to 6-15 MeV/u is described. The Isotope-Separator-On-Line (ISOL) method is used. A high-power driver accelerator produces radionuclides in a target that is closely coupled to an ion source and mass separator. By using a driver accelerator which can deliver a variety of beams and energies the radionuclide production mechanisms can be chosen to optimize yields for the … more
Date: February 24, 1999
Creator: Nolen, J. A.
Partner: UNT Libraries Government Documents Department
open access

CRT compatibility evaluation of LX-16 and Halthane 73-18

Description: A preliminary compatibility study was carried out between the plastic-bonded PETN-based high explosive LX-16 and the adhesive Halthane 73-18. The work, based on the Chemical Reactivity Test (CRT), used non-standard times and temperatures to find conditions corresponding to accelerated decomposition. This study is a prequel to a more comprehensive isothermal and thermal cycling study that will include both material evaluation and test fire.
Date: August 24, 1999
Creator: Foltz, M F; Reyes, P & Foster, P A
Partner: UNT Libraries Government Documents Department
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