Results 291 to 300 of about 52,672 (321)

An approximate BDDC preconditioner

Numerical Linear Algebra with Applications, 2007
AbstractThe balancing domain decomposition by constraints (BDDC) preconditioner requires direct solutions of two linear systems for each substructure and one linear system for a global coarse problem. The computations and memory needed for these solutions can be prohibitive if any one system is too large.
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Circulant Preconditioners Constructed from Kernels

SIAM Journal on Numerical Analysis, 1992
The concept of a model operator as a preconditioner is one of the widely used for the solution of large elliptic grid systems. During the last decade it gained a recognition in some ``nonelliptic'' applications like the solution of systems with Toeplitz matrix \(A\) which arise, for example, in signal processing and control theory.
Chan, Raymond H., Yeung, Man-Chung
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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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BDDC PRECONDITIONERS FOR ISOGEOMETRIC ANALYSIS

Mathematical Models and Methods in Applied Sciences, 2013
A Balancing Domain Decomposition by Constraints (BDDC) preconditioner for Isogeometric Analysis of scalar elliptic problems is constructed and analyzed by introducing appropriate discrete norms. A main result of this work is the proof that the proposed isogeometric BDDC preconditioner is scalable in the number of subdomains and quasi-optimal in the ...
L. Beirao da Veiga, D. Cho, L. Pavarino, S. Scacchi   +3 more
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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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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.
DeLong, M. A., Ortega, J. M.
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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, Pierre Alart, Philippe Doudet   +2 more
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Additive Schwarz Preconditioners

2002
The symmetric positive definite system arising from a finite element discretization of an elliptic boundary value problem can be solved efficiently using the preconditioned conjugate gradient method (cf. (Saad 1996)). In this chapter we discuss the class of additive Schwarz preconditioners, which has built-in parallelism and is particularly suitable ...
Susanne C. Brenner, L. Ridgway Scott
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Preconditioners Based on Fundamental Solutions

BIT Numerical Mathematics, 2005
A new type of preconditioner is used in solving systems of linear algebraic equations obtained from the finite difference discretization of partial differential equations. This preconditioner is a discretization of an approximate inverse given by a convolution-like operator with the fundamental solution as a kernel.
Brandén, H., Sundqvist, P.
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Circulant Preconditioners

2004
Abstract A circulant matrix is a special form of Toeplitz matrix where each row of the matrix is a circular shift of its preceding row; see (1.6). Because of the periodicity, circulant systems can be solved efficiently via a deconvolution by discrete Fast Fourier Transforms (FFTs); see Section 3.2.1.
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