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Multidimensional first and second order symmetric strang splitting for hyperbolic systems

Description: We propose an algebraic basis for symmetric Strang splitting for first and second order accurate schemes for hyperbolic systems in N dimensions. Examples are given for two and three dimensions. Optimal stability is shown for symmetric systems. Lack of strong stability is shown for a non-symmetric example. Some numerical examples are presented for some Euler-like constant coefficient problems.
Date: January 1, 2008
Creator: Kucharik, Milan & Wendroff, Burton
Partner: UNT Libraries Government Documents Department
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Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

Description: Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation m… more
Date: January 1, 1998
Partner: UNT Libraries Government Documents Department
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The interaction of laser driven shock waves with a spherical density perturbation

Description: Strong shock waves produced by illumination of a CH target by laser produced x-rays were driven through a copper sphere. The motion and deformation of the sphere were measured using radiographs generated by backlighting the sphere with a large area backlighter. The sphere became non-spherical after the passage of the shock, having a complicated down-stream structure. This was an instability-induced structure that was predicted by calculations. The experiment is a convenient laboratory model of … more
Date: January 8, 1999
Creator: Perry, T S; Klein, R I; Budil, K S & Bach, D R
Partner: UNT Libraries Government Documents Department
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A 3-Axis Force Balanced Accelerometer Using a Single Proof-Mass

Description: This paper presents a new method for wideband force balancing a proof-mass in multiple axes simultaneously. Capacitive position sense and force feedback are accomplished using the same air-gap capacitors through time multiplexing. Proof of concept is experimentally demonstrated with a single-mass monolithic surface micromachined 3-axis accelerometer.
Date: April 1997
Creator: Lemkin, M.A.; Boser, B.E.; Auslander, D. & Smith, J.
Partner: UNT Libraries Government Documents Department
open access

Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

Description: Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation m… more
Date: March 12, 1998
Partner: UNT Libraries Government Documents Department
open access

Application of Integrated Reservoir management and Reservoir Characterization to Optimize Infill Drilling

Description: Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation m… more
Date: August 31, 1997
Creator: Pregger, B.; Davies, D.; Moore, D.; Freeman, G.; Callard, J.; Nevans, J.W. et al.
Partner: UNT Libraries Government Documents Department
open access

Potentials of Mean Force Between Rigid Solvated Polymers

Description: In this letter we discusses the first application of 3-dimensional nonlocal density functional calculations to the interactions of solvated rigid polymers. The three cases considered are cylindrical polymers, bead-chain polymers, and periodic polymers. We calculate potentials of mean force, and show that polymer surface structure plays a critical role in determining the solvation energy landscape which in turn controls routes to assembly of the macromolecules.
Date: September 29, 1999
Creator: FRINK, LAURA J.D. & SALINGER, ANDREW G.
Partner: UNT Libraries Government Documents Department
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Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir

Description: Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation m… more
Date: January 31, 1998
Creator: Taylor, Archie R.; Justice, James J. & Hickman, T. Scott
Partner: UNT Libraries Government Documents Department
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New laser driver for physics modeling codes using unstructured 3d grids

Description: We present a status report on the current state of development, testing and application of a new scheme for laser beam evolution and power deposition on three-dimensional unstructured grids. The scheme is being encapsulated in a C++ library for convenient porting to existing modeling codes. We have added a new ray propagator that is second order in time, allowing rays to refract within computational zones as well as at zone interfaces. In a globally constant free-electron density gradient on a … more
Date: February 1, 1999
Creator: Kaiser, T; Milovich, J L; Prasad, M K & Shestakov, A I
Partner: UNT Libraries Government Documents Department
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AN INTEGRATED MULTI-COMPONENT PROCESSING AND INTERPRETATION FRAMEWORK FOR 3D BOREHOLE SEISMIC DATA

Description: This report covers the November 2004-March 2005 time period. A mid year project review meeting was held at DOE facilities on November 30th. Work has been performed successfully on several tasks 3 through 15. Most of these tasks have been executed independently. We progressed steadily and completed some of the sub-tasks, while others are still on going. We achieved the goals that we had set up in the task schedule. Reviewing the results of this work period indicates that our plan is solid and we… more
Date: April 15, 2005
Creator: Karrenbach, M.
Partner: UNT Libraries Government Documents Department
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3-D Target Location from Stereoscopic SAR Images

Description: SAR range-Doppler images are inherently 2-dimensional. Targets with a height offset lay over onto offset range and azimuth locations. Just which image locations are laid upon depends on the imaging geometry, including depression angle, squint angle, and target bearing. This is the well known layover phenomenon. Images formed with different aperture geometries will exhibit different layover characteristics. These differences can be exploited to ascertain target height information, in a stereosco… more
Date: October 1, 1999
Creator: Doerry, Armin W.
Partner: UNT Libraries Government Documents Department
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Three-dimensional high-resolution simulations of Rayleigh-Taylor instability and turbulent mixing

Description: Preliminary results of three-dimensional simulations of compressible Rayleigh-Taylor instability and turbulent mixing in an ideal gas using the piecewise-parabolic method (PPM) (with and without molecular dissipation terms) are presented. Simulations with spatial resolutions up to 512{sup 3} were performed. Two types of convergence studies are presented. Statistical analyses of the data are discussed, include: 1: spectra, and; 2) horizontally-averaged terms in the kinetic energy and onstrophy d… more
Date: June 1, 1997
Creator: Schilling, O.; Cohen, R. H.; Dannevik, W. P.; Dimits, A. M.; Eliason, D. E.; Mirin, D. H. et al.
Partner: UNT Libraries Government Documents Department
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Three-dimensional high-resolution simulations of compressible rayleigh-taylor instability and turbuelnt mixing

Description: Preliminary results of three-dimensional simulations of compressible Rayleigh-Taylor instabilities and turbulent mixing in an ideal gas using the piecewise-parabolic method (PPM) with and without molecular dissipation terms are presented. Simulations with spatial resolutions up to 512 were performed. Two types of convergence studies are presented. The first investigates the Reynolds numbers for which the simulations with molecular dissipation are converged with respect to spatial resolution, an… more
Date: June 12, 1997
Creator: Schilling, O.; Cohen, R. H.; Dannevik, W. P.; Dimits, A. M.; Eliason, D. E.; Mirin, A. A. et al.
Partner: UNT Libraries Government Documents Department
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A null-steering viewpoint of interferometric SAR

Description: Interferometric synthetic aperture radar (IFSAR) extends the two-dimensional imaging capability of traditional synthetic aperture radar to three-dimensions by using an aperture in the elevation plane to estimate the 3-D structure of the target. The operation of this additional aperture can be viewed from a null-steering point of view, rather than the traditional phase determination point of view. Knowing that IFSAR can be viewed from the null-steering perspective allows one to take advantage of… more
Date: May 2, 2000
Creator: Bickel, Douglas L.
Partner: UNT Libraries Government Documents Department
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Physical modeling of small shallow conductive 3-D targets with high-frequency electromagnetics

Description: The goal of this study is to show that physical modeling can provide important support for three-dimensional (3D) interpretation of electromagnetic geophysical data for environmental problems. This is specially true when high-frequency electromagnetic methods are used, which are difficult to model with existing 3D forward modeling programs. Existing electromagnetic geophysical systems usually operate in the frequency range of a few hertz to several hundred hertz. For environmental problems, suc… more
Date: September 1, 1996
Creator: Birken, R.A.; Poulton, M. & Sterngerg, B.K.
Partner: UNT Libraries Government Documents Department
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Dislocation dynamics: simulation of plastic flow of bcc metals

Description: This is the final report for the LDRD strategic initiative entitled ''Dislocation Dynamic: Simulation of Plastic Flow of bcc Metals'' (tracking code: 00-SI-011). This report is comprised of 6 individual sections. The first is an executive summary of the project and describes the overall project goal, which is to establish an experimentally validated 3D dislocation dynamics simulation. This first section also gives some information of LLNL's multi-scale modeling efforts associated with the plast… more
Date: February 20, 2001
Creator: Lassila, D H
Partner: UNT Libraries Government Documents Department
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A fully implicit method for 3D quasi-steady state magnetic advection-diffusion.

Description: We describe the implementation of a prototype fully implicit method for solving three-dimensional quasi-steady state magnetic advection-diffusion problems. This method allows us to solve the magnetic advection diffusion equations in an Eulerian frame with a fixed, user-prescribed velocity field. We have verified the correctness of method and implementation on two standard verification problems, the Solberg-White magnetic shear problem and the Perry-Jones-White rotating cylinder problem.
Date: September 1, 2009
Creator: Siefert, Christopher & Robinson, Allen Conrad
Partner: UNT Libraries Government Documents Department
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3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

Description: Under ER63662, 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface, we have completed a number of subprojects associated with the Hill Air Force Base (HAFB) high resolution 3-D reflection/tomography dataset.
Date: December 1, 2004
Creator: Levander, Alan R.
Partner: UNT Libraries Government Documents Department
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Determination of 3D Equilibria from Flux Surface Knowledge Only

Description: We show that the method of Christiansen and Taylor, from which complete tokamak equilibria can be determined given only knowledge of the shape of the flux surfaces, can be extended to 3-dimensional equilibria, such as those of stellarators. As for the tokamak case, the given geometric knowledge has a high degree of redundancy, so that the full equilibrium can be obtained using only a small portion of that information.
Date: November 12, 2001
Creator: Mynick, H.E. & Pomphrey, N.
Partner: UNT Libraries Government Documents Department
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Coupling impedance of a long slot and an array of slots in a circular vacuum chamber

Description: We find the real part of the longitudinal impedance for both a small hole and a long slot in a beam vacuum chamber with a circular cross section. The slot can be arbitrarily long; the only requirement on the dimensions of the slots is that its width be much smaller than c/w. Regular array of N slots periodically distributed along the pipe is also considered.
Date: June 1, 1995
Creator: Stupakov, G.V.
Partner: UNT Libraries Government Documents Department
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