The need to produce a continuous representation of a curve (or part of a curve) from a set of discretely defined data arises in many metrological applications. In this paper we are interested in the reconstruction of ...
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The need to produce a continuous representation of a curve (or part of a curve) from a set of discretely defined data arises in many metrological applications. In this paper we are interested in the reconstruction of continuous surface texture profiles defined only at discretely obtained points. By reconstructing surface profiles accurately, with elements of numerical safety being taken into account, we can provide a mathematically sound basis on which to compute surface texture profile parameters [1], especially those that do not allow exact evaluation with discrete data points. Examples are given to illustrate the advantages of using this reconstruction method.
In this paper we are interested in the approximation of continuous surface texture profiles defined only at discretely obtained points. A continuous representation is required in order to be able to apply filtration m...
In this paper we are interested in the approximation of continuous surface texture profiles defined only at discretely obtained points. A continuous representation is required in order to be able to apply filtration methods that assume uniform data spacing to practical data that in general is not uniformly spaced. By reconstructing surface profiles as natural cubic spline interpolants accurately using numerically stable fitting algorithms, we can provide a mathematically sound basis on which to compute surface texture profile parameters. As an important direct benefit, parameters involving the integrals of surface profiles can be calculated directly from the spline interpolant. Examples are given to illustrate the advantages of using this reconstruction method.
The teracluster LSSC-II installed at the State Key laboratory of scientific and engineeringcomputing, Chinese Academy of Sciences is one of the most powerful PC clusters in China. It has a peek performance of 2Tflops...
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The teracluster LSSC-II installed at the State Key laboratory of scientific and engineeringcomputing, Chinese Academy of Sciences is one of the most powerful PC clusters in China. It has a peek performance of 2Tflops. With a Linpack performance of 1.04Tflops, it is ranked at the 43rd place in the 20th TOP500 List (November 2002), 51st place in the 21st TOP500 List (June 2003), and the 82nd place in the 22nd TOP500 List (November 2003) with a new Linpack performance of 1.3Tflops. In this paper, we present some design principles of this cluster, as well as its applications in some large-scale numerical simulations.
Previously developed constitutive models and solution algorithms for continuum‐level anisotropic elastoplastic material strength and an isotropic damage model TEPLA have been implemented in the three‐dimensional Eul...
Previously developed constitutive models and solution algorithms for continuum‐level anisotropic elastoplastic material strength and an isotropic damage model TEPLA have been implemented in the three‐dimensional Eulerian hydrodynamics code known as CONEJO. The anisotropic constitutive modeling is posed in an unrotated material frame of reference using the theorem of polar decomposition to compute rigid‐body rotation. TEPLA is based upon the Gurson flow surface (a potential function used in conjunction with the associated flow law). The original TEPLA equation set has been extended to include anisotropic elastoplasticity and has been recast into a new implicit solution algorithm based upon an eigenvalue scheme to accommodate the anisotropy. This algorithm solves a two‐by‐two system of nonlinear equations using a Newton‐Raphson iteration scheme. Simulations of a shaped‐charge jet formation, a Taylor cylinder impact, and an explosively loaded hemishell were selected to demonstrate the utility of this modeling capability. The predicted deformation topology, plastic strain, and porosity distributions are shown for the three simulations.
Previously developed constitutive models and solution algorithms for anisotropic elastoplastic material strength have been implemented in the three‐dimensional Conejo hydrodynamics code. The anisotropic constitutive ...
Previously developed constitutive models and solution algorithms for anisotropic elastoplastic material strength have been implemented in the three‐dimensional Conejo hydrodynamics code. The anisotropic constitutive modeling is posed in an unrotated material frame of reference using the theorem of polar decomposition to obtain rigid body rotation. Continuous quadratic yield functions fitted from polycrystal simulations for a metallic hexagonal‐close‐packed structure were utilized. Simple rectangular shear problems, R‐Value problems, and Taylor cylinder impact data were used to verify and validate the implementation of the anisotropic model. A stretching rod problem (involving large strain and high strain‐rate deformation) was selected to investigate the effects of material anisotropy. Conejo simulations of rod topology were compared for two anisotropic cases.
Focuses on a study which determined the geometry meaning of the maxima of the CDT mathematical subproblem's dual function. Properties of trust region subproblem; Approximation of the CDT feasible region; Relations...
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Focuses on a study which determined the geometry meaning of the maxima of the CDT mathematical subproblem's dual function. Properties of trust region subproblem; Approximation of the CDT feasible region; Relations between the CDT problem and the trust region problem; Illustration of the geometry meaning of the jump parameter.
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