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Showing 1 to 11 of 11 for “"Multiscale Problems"”.
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Non-Intrusive Extension of a Generalized Finite Element Method for Multiscale Problems to the Abaqus Analysis Platform
Several classes of important engineering problems – in this case, problems exhibiting sharp thermal gradients – have solution features spanning multiple spatial scales of interest and, therefore, necessitate advanced hp finite element discretizations. Although hp-FEM is unavailable off-the-shelf in …
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Robust computational methods to simulate slow-fast dynamical systems governed by predator-prey models
Numerical approximations of multiscale problems of important applications in ecology are investigated. One of the class of models considered in this work are singularly perturbed (slow-fast) predator-prey systems which are characterized by the presence of a very small positive parameter …
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Data Assimilation and Applications in Forecasting
… commonly used in the EnKF, can be extended to multiscale problems. Rather than using a single length scale when localizing, we construct a localized covariance matrix through the estimation of eigenvectors. Specifically, we estimate the leading large-scale eigenvectors from a sample covari- …
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Experimental and Novel Analytic Results for Couplings in Ordered Submicroscopic Systems: from Optomechanics to Thermomechanics
Theoretical modelling of challenging multiscale problems arising in complex (and sometimes bioinspired) solids are presented. Such activities are supported by analytical, numerical and experimental studies. For instance, this is the case for studying the response of hierarchical and …
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Discontinuous Galerkin Based Multi-Domain Multi-Solver Technique for Efficient Multiscale Electromagnetic Modeling
… methods provide an efficient option for modeling multiscale problems. With the help of the Riemann solver (upwind flux), a discontinuous Galerkin based multi-domain multi-solver technique is introduced in this work for multiscale electromagnetic modeling. Specifically, the proposed technique …
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A Hybrid Spectral-Element / Finite-Element Time-Domain Method for Multiscale Electromagnetic Simulations
… (FETD) method for transient analysis of multiscale electromagnetic problems, where electrically fine structures with details much smaller than a typical wavelength and electrically coarse structures comparable to or larger than a typical wavelength coexist.</p><p>Simulations of multiscale …
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Improved conditioning and accuracy of a two-scale generalized finite element method for fracture mechanics
Many problems of engineering relevance in computational mechanics involve analysis of structural behavior spanning different spatial scales. Examples of such industrial problems include fracture in engine components, structural members of aircrafts, and pipeline joints. The presence of small cracks …
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Numerical analysis of radio-frequency sheath-plasma interactions in the ion cyclotron range of frequencies
… element technique and is applied to various problems in the one-dimensional (1D) and two-dimensional (2D) domains corresponding to simplified models for the poloidal plane of a tokamak. The present code solves for plasma waves based on the cold plasma model subject to the sheath boundary …
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Discontinuous Galerkin methods for compressible and incompressible flows on space-time adaptive meshes
… sub-cell averages. Moreover, handling typical multiscale problems, dynamic adaptive mesh refinement (AMR) and adaptive polynomial order methods are probably the two main ways of preserving accuracy and efficiency, and saving computational effort. The here adopted AMRapproach is the so called …
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Computational modeling and simulation of nonlinear electromagnetic and multiphysics problems
… nonlinear electromagnetic and multiphysics problems are modeled and simulated using various three-dimensional full-wave methods in the time domain. The problems under consideration fall into two categories. One is nonlinear electromagnetic problems with the nonlinearity embedded in either …