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Showing 1 to 20 of 22 for “"Adaptive Refinement"”.
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Adaptive refinement methods for singularly perturbed convection-diffusion problems
Contains fulltext : 145683.pdf (Publisher’s version ) (Open Access)
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Fully anisotropic split-tree adaptive refinement mesh generation using tetrahedral mesh stitching
… and gradation. Fully Anisotropic Split-Tree Adaptive Refinement (FASTAR) is a code that allows the user to exert a great deal of control and ultimately generate a valid, geometry conforming mesh. Due to the split-tree nature and the use of volumetric pixels (voxels), non-unit aspect ratio …
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Generation and optimization of spacing fields
… (CFD) simulations. Mesh adaptation through refinement and smoothing can improve the accuracy of the CFD solution. In order to perform adaptive refinement or smoothing a spacing field is needed to define the desired edge sized in mesh. The objectives of this research are to generate spacing …
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Unified Multilevel Adaptive Finite Element Methods for Elliptic Problems
… with near optimal efficiency through the uses of adaptive refinement and multigrid solution techniques. It is our goal to develop a more unified approach to the combined process of adaptive refinement and multigrid solution which can be used with high order finite elements. The basic step of the …
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Uma estratégia de refinamento auto-adaptativo versão h do método dos elementos finitos aplicada a problemas bi-dimensionais regidos pela equação de campo
In this work a self-adaptive refinement procedure (h-version) for the Finite Element Method (FEM) solution of two dimensional potential problems is studied. The mesh refinement strategy and the a-posteriori error analysis are also discussed. The Galerkin formulation for FEM is utilized and the …
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A Spacetime Discontinuous Galerkin Method for Hyperbolic Conservation Laws
… the performance of the SDG method, the h-adaptive refinement scheme, and the diffusion operator for applications of the inviscid Euler equations in one and two spatial dimensions are presented.
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Tools for electromagnetic field simulation in the KATRIN experiment
… harmonic expansion and interpolation from an adaptive-refinement field mesh is described within the object-oriented KatrinField framework, as well as an analysis of their comparative strengths and weaknesses in reproducing the electromagnetic fields found in KATRIN.
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Numerical Simulation of Multiphase Flow in Fractured Porous Media
… The method features unstructured grids, adaptive refinement and multigrid methods. It is implemented for twodimensional and threedimensional complex problems with several million unknowns. Additionally, a discontinuous Galerkin method for the groundwater flow equation and its multigrid …
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Finite element methods for implicit solvent models
… and the choice of elements on conditioning and adaptive refinement. In a series of numerical experiments, we compare the finite element methods when applied to the problem of computing the solvation free energy for realistic molecules of varying size. The inclusion of steric effects is important …
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A comparative study of shared memory parallelism on regular and irregular data structures using OpenMP and Galois
… which operates on a triangulated mesh with adaptive refinement; is evaluated. It is found that OpenMP is a simple yet powerful tool for parallelization of most regular applications and workloads. Galois, which is specially designed for irregular data patterns, performs well for graph like …
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A new software framework for unstructured mesh representation and manipulation
… partitioning, phantom node data updates, adaptive refinement, derefinement and load balancing. What makes the framework unique is a focus on generality: like a database, the user provides a programmatic schema defining the structure of the mesh, including topological descriptions of the …
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On the Potential Impact of Curved Meshing for Higher-order Adaptive Mesh Simulations
Higher order, adaptive finite element methods have demonstrated the ability to significantly reduce the human and computational cost of accurately approximating the solution to partial differential equations (PDEs). In this thesis, we consider the potential advantages of incorporating higher-order …
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A nonlinear interface formulation for frictional contact
… are typically associated with large sliding or adaptive refinement on one side of the interface to capture localized nonlinear behavior due to large deformations, damage and inelasticity. The use of NCMs, however, presents a number of numerical issues; the main challenge with such …
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Operator-adapted finite element wavelets : theory and applications to a posteriori error estimation and adaptive computational modeling
… approach for a posteriori error estimation and adaptive mesh refinement in finite element analysis using multiresolution signal processing principles. Given a sequence of nested discretizations of a domain we begin by constructing approximation spaces at each level of discretization spanned by …
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Adjoint-based space-time adaptive solution algorithms for sensitivity analysis and inverse problems
… refined grids computationally prohibitive. Adaptive refinement of meshes and time steps allows to capture the phenomena of interest while keeping the cost of a simulation tractable on the current hardware. Many fields in science and engineering require the solution of inverse problems where …
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Adjoint Error Estimation for Elastohydrodynamic Lubrication
… predictions of the error as uniform meshes. Adaptive refinement is undertaken, with the mesh being refined using the adjoint error estimate. Results for this are presented for both the model free-boundary problem and the full EHL problem. This is shown to enable the accurate calculation of …
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Adaptive load balancing for HPC applications
… and are using irregular structures and adaptive refinement techniques, resulting in load imbalance. Moreover, systems are becoming more complex. The number of cores per node is increasing substantially and nodes are becoming heterogeneous. High variability in the performance of the …
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Least squares spectral element method for laminar and turbulent flows, –continuous and discontinuous approaches–
… as it does not need blocking communication. H-refinement is implemented for both steady and unsteady test cases using the discontinuous formulation. Feature based adaptation is utilized in the adaptive refinement process. Least squares method is known to be conditionally stable. In this study, …
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Validated global multiobjective optimization of trajectories in nonlinear dynamical systems
… bounds converge to exact bounds with increasing refinement of the state space partition, an adaptive refinement can produce asymptotically convergent bounds on optimal trajectories. We compute a lower bound on each stepwise transition between state subregions by a novel "interval linearization" …
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Failure processes in soft and quasi-brittle materials with nonhomogeneous microstructures
… operators. The first operator we propose is adaptive element-splitting, and the second is adaptive mesh refinement. Both operators are designed to improve the ability of unstructured polygonal meshes to capture crack patterns in dynamic cohesive fracture simulations. However, we demonstrate …
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