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Proposition de préconditionneurs pseudo-différentiels pour l’équation CFIE de l’électromagnétisme

David P. Levadoux (2005)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We present a weak parametrix of the operator of the CFIE equation. An interesting feature of this parametrix is that it is compatible with different discretization strategies and hence allows for the construction of efficient preconditioners dedicated to the CFIE. Furthermore, one shows that the underlying operator of the CFIE verifies an uniform discrete Inf-Sup condition which allows to predict an original convergence result of the numerical solution of the CFIE to the exact one.

Proposition de préconditionneurs pseudo-différentiels pour l'équation CFIE de l'électromagnétisme

David P. Levadoux (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

On exhibe dans cette note une paramétrix (au sens faible) de l'opérateur sous-jacent à l'équation CFIE de l'électromagnétisme. L'intérêt de cette paramétrix est de se prêter à différentes stratégies de discrétisation et ainsi de pouvoir être utilisée comme préconditionneur de la CFIE. On montre aussi que l'opérateur sous-jacent à la CFIE satisfait une condition Inf-Sup discrète uniforme, applicable aux espaces de discrétisation usuellement rencontrés en électromagnétisme, et qui permet d'établir...

Remarks on polynomial methods for solving systems of linear algebraic equations

Krzysztof Moszyński (1992)

Applications of Mathematics

For a large system of linear algebraic equations A x = b , the approximate solution x k is computed as the k -th order Fourier development of the function 1 / z , related to orthogonal polynomials in L 2 ( Ω ) space. The domain Ω in the complex plane is assumed to be known. This domain contains the spectrum σ ( A ) of the matrix A . Two algorithms for x k are discussed. Two possibilities of preconditioning by an application of the so called Richardson iteration process with a constant relaxation coefficient are proposed. The case...

Resilient asynchronous primal Schur method

Guillaume Gbikpi-Benissan, Frédéric Magoulès (2022)

Applications of Mathematics

This paper introduces the application of asynchronous iterations theory within the framework of the primal Schur domain decomposition method. A suitable relaxation scheme is designed, whose asynchronous convergence is established under classical spectral radius conditions. For the usual case where local Schur complement matrices are not constructed, suitable splittings based only on explicitly generated matrices are provided. Numerical experiments are conducted on a supercomputer for both Poisson's...

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