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194
Stabilized shock hydrodynamics: II. Design and physical interpretation of the SUPG operator for Lagrangian computations
, 2005
"... A new SUPGstabilized formulation for Lagrangian Hydrodynamics of materials satisfying the MieGruneisen equation of state was presented in the first paper of the series [7]. This article investigates in more detail the design of SUPG stabilization, focusing on its multiscale and physical interpreta ..."
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Cited by 7 (1 self)
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of the SUPG operator as a subgrid interaction model. Acknowledgments This research was partially funded by the DOE NNSA Advanced Scientific Computing Program and the Computer Science Research Institute at Sandia National Laboratories. The author would like to thank Tom Hughes, Mark Christon, and John Shadid
Meshfree and particle methods and their applications
 Applied Mechanics Review
, 2002
"... Recent developments of meshfree and particle methods and their applications in applied mechanics are surveyed. Three major methodologies have been reviewed. First, smoothed particle hydrodynamics �SPH � is discussed as a representative of a nonlocal kernel, strong form collocation approach. Second, ..."
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Cited by 78 (7 self)
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Recent developments of meshfree and particle methods and their applications in applied mechanics are surveyed. Three major methodologies have been reviewed. First, smoothed particle hydrodynamics �SPH � is discussed as a representative of a nonlocal kernel, strong form collocation approach. Second, meshfree Galerkin methods, which have been an active research area in recent years, are reviewed. Third, some applications of molecular dynamics �MD � in applied mechanics are discussed. The emphases of this survey are placed on simulations of finite deformations, fracture, strain localization of solids; incompressible as well as compressible flows; and applications of multiscale methods and nanoscale mechanics. This review article includes 397 references. �DOI: 10.1115/1.1431547� 1
High Performance Fortran Language Specification
, 1994
"... processors as a userdeclared Cartesian mesh Physical processors ALIGN (static) or REALIGN (dynamic) DISTRIBUTE (static) or REDISTRIBUTE (dynamic) Optional implementationdependent directive The underlying assumptions are that an operation on two or more data objects is likely to be carried o ..."
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Cited by 65 (0 self)
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processors as a userdeclared Cartesian mesh Physical processors ALIGN (static) or REALIGN (dynamic) DISTRIBUTE (static) or REDISTRIBUTE (dynamic) Optional implementationdependent directive The underlying assumptions are that an operation on two or more data objects is likely to be carried out much faster if they all reside in the same processor, and that it may be possible to carry out many such operations concurrently if they can be performed on different processors. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 22 SECTION 3. DATA ALIGNMENT AND DISTRIBUTION DIRECTIVES Fortran 90 provides a number of features, notably array syntax, that make it easy for a compiler to determine that many operations may be carried out concurrently. The HPF directives provide a way to inform the compiler of the recommendation that certain data objects should reside in the same processor: if two data objects a...
The Terrestrial Ring Current: Origin, Formation, And Decay
, 1998
"... . The terrestrial ring current is an electric current flowing toroidally around the Earth, centered at the equatorial plane and at altitudes of #10,000  60,000 km. Changes in this current are responsible for global decreases in the Earth's surface magnetic field, which are known as geomagneti ..."
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Cited by 47 (2 self)
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. The terrestrial ring current is an electric current flowing toroidally around the Earth, centered at the equatorial plane and at altitudes of #10,000  60,000 km. Changes in this current are responsible for global decreases in the Earth's surface magnetic field, which are known as geomagnetic storms. Intense geomagnetic storms have severe effects on technological systems, such as disturbances or even permanent damage to telecommunication and navigation satellites, telecommunication cables, and power grids. The main carriers of the storm ring current are positive ions, with energies from #1 keV to a few hundred keV, which are trapped by the geomagnetic field and undergo an azimuthal drift. The ring current is formed by the injection of ions originating in the solar wind and the terrestrial ionosphere. The injection process involves electric fields, associated with enhanced magnetospheric convection and/or magnetospheric substorms. The quiescent ring current is carried mainly by proto...
RAPID: The imaging energetic particle spectrometer on
 Cluster, Space Sci. Rev
, 1997
"... Abstract. The RAPID spectrometer (Research with Adaptive Particle Imaging Detectors) for the Cluster mission is an advanced particle detector for the analysis of suprathermal plasma distributions in the energy range from 20–400 keV for electrons, 40 keV–1500 keV (4000 keV) for hydrogen, and 10 keV n ..."
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Cited by 24 (7 self)
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Abstract. The RAPID spectrometer (Research with Adaptive Particle Imaging Detectors) for the Cluster mission is an advanced particle detector for the analysis of suprathermal plasma distributions in the energy range from 20–400 keV for electrons, 40 keV–1500 keV (4000 keV) for hydrogen, and 10 keV nucl,1 –1500 keV (4000 keV) for heavier ions. Novel detector concepts in combination with pinhole acceptance allow the measurement of angular distributions over a range of 180 in polar angle for either species. Identification of the ionic component (particle mass A) is based on a twodimensional
Efficient Subdivision of FiniteElement Datasets into Consistent Tetrahedra
 in Proceedings of IEEE Visualization '97
, 1997
"... This paper discusses the problem of subdividing unstructured mesh topologies containing hexahedra, prisms, pyramids and tetrahedra into a consistent set of only tetrahedra, while preserving the overall mesh topology. Efficient algorithms for volume rendering, isocontouring and particle advection ex ..."
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Cited by 12 (3 self)
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This paper discusses the problem of subdividing unstructured mesh topologies containing hexahedra, prisms, pyramids and tetrahedra into a consistent set of only tetrahedra, while preserving the overall mesh topology. Efficient algorithms for volume rendering, isocontouring and particle advection exist for mesh topologies comprised solely of tetrahedra. General finiteelement simulations however, consist mainly of hexahedra, and possibly prisms, pyramids and tetrahedra. Arbitrary subdivision of these mesh topologies into tetrahedra can lead to discontinuous behavior across element faces. This will show up as visible artifacts in the isocontouring and volume rendering algorithms, and lead to impossible face adjacency graphs for many algorithms. We present here, various properties of tetrahedral subdivisions, and an algorithm for determining a consistent subdivision containing a minimal set of tetrahedra.
Dispersive Properties of the Natural Element Method
, 2000
"... The Natural Element Method (NEM) is a meshfree numerical method for the solution of partial differential equations. In the natural element method, natural neighbor coordinates, which are based on the Voronoi tesselation of a set of nodes, are used to construct the interpolant. The performance of NEM ..."
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Cited by 7 (4 self)
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The Natural Element Method (NEM) is a meshfree numerical method for the solution of partial differential equations. In the natural element method, natural neighbor coordinates, which are based on the Voronoi tesselation of a set of nodes, are used to construct the interpolant. The performance of NEM in twodimensional linear elastodynamics is investigated. A standard Galerkin formulation is used to obtain the weak form and a centraldifference time integration scheme is chosen for time history analyses. Two different applications are considered: vibration of a cantilever beam and dispersion analysis of the wave equations. The NEM results are compared to nite element and analytical solutions. Excellent dispersive properties of NEM are observed and good agreement with analytical solutions is obtained.
Computational bifurcation and stability studies of the 8:1 thermal cavity problem
 Int. J. Numer Methods Fluids
"... Stability analysis algorithms coupled with a robust NewtonKrylov steady state iterative solver are used to understand the behavior of the 2D model problem of thermal convection in a 8:1 differentially heated cavity. Parameter continuation methods along with bifurcation and linear stability analysis ..."
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Cited by 7 (4 self)
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Stability analysis algorithms coupled with a robust NewtonKrylov steady state iterative solver are used to understand the behavior of the 2D model problem of thermal convection in a 8:1 differentially heated cavity. Parameter continuation methods along with bifurcation and linear stability analysis are used to study transition from steady to transient flow as a function of Rayleigh number. To carry out this study the steady state form of the governing PDEs is discretized using a Galerkin/Least Squares Finite Element formulation, and solved on parallel computers using a fully coupled Newton method and preconditioned Krylov iterative linear solvers. Linear stability analysis employing a large scale eigenvalue capability is used to determine the stability of the steady solutions. The boundary between steady and time dependent flows is determined by a Hopf bifurcation tracking capability that is used to directly track the instability with respect to the aspect ratio of the system and with respect to mesh resolution. The effect of upwinding stabilization terms in the finite element formulation on the computed value of critical Rayleigh number is investigated. The Hopf bifurcation signaling the onset of flow is determined to occur at a critical Rayleigh number of. 1.
Results 1  10
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194