Results 181 to 190 of about 37,446 (199)

Preconditioners for Multi-Screen Scattering

2022 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2022
In this contribution, a well-conditioned method for the modelling of scattering by so-called multi-screens or PEC sheets including junctions is introduced. The method starts from the inflated screen approach by Claeys and Hiptmair. We introduce a Calderón preconditioner and a suitable discretisation scheme.
Cools, Kristof, Urzua-Torres, Carolina
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Multi-p Preconditioners

SIAM Journal on Scientific Computing, 1997
In analogy with the multigrid method, the authors present a solution method for problems based on the \(p\)-version of the finite element method whereby degrees of freedom associated with approximation order \(p\) are visited at once and separately from those of approximation order \(p-1\) and \(p+1\).
I. Norman Katz, Ning Hu, Xian-zhong Guo
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Optimal Equivalent Preconditioners

SIAM Journal on Numerical Analysis, 1993
Preconditioning strategies for elliptic partial differential operators and their discrete counterparts are compared by a model problem. The technique uses a selfadjoint positive definite operator \(B\) as the preconditioner for the nonselfadjoint convection-diffusion operator \(A\). Preconditioning is done by \(A\)'s leading term plus a positive zeroth
James S. Otto, Thomas A. Manteuffel
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SOR as a preconditioner II

Applied Numerical Mathematics, 1998
This is the second part of a paper concerned with the use of successive overrelaxation (SOR) as a preconditioner for the nonsymmetric iterative solver GMRES [for the first part see ibid. 18, 431-440 (1995; Zbl 0840.65018)]. The focus of the second part is on parallel implementation issues.
J. M. Ortega, M. A. DeLong
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Preconditioners for block Toeplitz systems based on circulant preconditioners

Numerical Algorithms, 2001
The numerical solution of block Toeplitz systems by preconditioned conjugate gradient methods is considered. Two types of preconditioners based on circulant preconditioners are proposed by combining the ideas which are used in the construction of circulant preconditioners with Toeplitz-like preconditioners.
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A Multilevel AINV Preconditioner

Numerical Algorithms, 2002
An algebraic multilevel approximate inverse preconditioner, which uses the same design as the algebraic multigrid algorithm, is proposed for solving efficiently symmetric positive definite sparse linear systems in conjunction with preconditioned conjugate gradient method.
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On the Schur component preconditioners

Computers & Structures, 1999
Summary: Some representations of the \(H^{1/2}\) norm are used as Schur complement preconditioners in preconditioned conjugate gradient based domain decomposition algorithms for elliptic problems. These norm representations are efficient preconditioners.
A. Krebsz, B. Kiss
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Some Properties of the Optimal Preconditioner and the Generalized Superoptimal Preconditioner

Numerical Mathematics: Theory, Methods and Applications, 2010
The optimal preconditioner and the superoptimal preconditioner were proposed in 1988 and 1992 respectively. They have been studied widely since then. Recently, Chen and Jin [6] extend the superoptimal preconditioner to a more general case by using the Moore-Penrose inverse.
Xiao-Qing Jin, Hong-Kui Pang
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Friction and Preconditioners

1995
Many structural analysis problems are concerned with friction contact phenomena. These problems are difficult to formulate and even more to solve because they are governed by multivalued tribological laws and some numerical resolutions can lead to unsymmetric operators.
Frédéric Lebon, Philippe Doudet, Pierre Alart   +2 more
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Structuring preconditioners for unstructured meshes

Russian Journal of Numerical Analysis and Mathematical Modelling, 1996
The authors develop a fictitious space technique for the construction of preconditioners for stiffness matrices generated by the finite element method using unstructured meshes. A comparison of the results of numerical experiments for the above preconditioners is also made.
Dyadechko, V. G., Iliash, Yuri, Vassilevski, Yu. V.   +2 more
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