Results 21 to 30 of about 1,731 (272)
Mathematics, 2021 The paper deals with the Stokes flow subject to the threshold leak boundary conditions in two and three space dimensions. The velocity–pressure formulation leads to the inequality type problem that is approximated by the P1-bubble/P1 mixed finite ...
Jaroslav Haslinger +3 more
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Condition number estimation of preconditioned matrices. [PDF]
PLoS ONE, 2015 The present paper introduces a condition number estimation method for preconditioned matrices. The newly developed method provides reasonable results, while the conventional method which is based on the Lanczos connection gives meaningless results.
Noriyuki Kushida
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Mathematical Modelling and Analysis, 2013 A preconditioned iterative solution method is presented for nonlinear parabolic transport systems. The ingredients are implicit Euler discretization in time and finite element discretization in space, then an outer-inner (outer damped inexact Newton ...
Janos Karatson, Tamas Kurics
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m-Step Preconditioned Conjugate Gradient Methods [PDF]
SIAM Journal on Scientific and Statistical Computing, 1985 The paper deals with the solution of a sparse system of symmetric positive definite linear equations by preconditioned conjugate gradient methods. Necessary and sufficient conditions are found for the applicability of preconditioners that are based on taking m steps of an iterative method. The computer implementation of these methods is discussed.
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Shock and Vibration, 2021 The full-waveform inversion (FWI) of a Love wave has become a powerful tool for shallow-surface site characterization. In classic conjugate gradient algorithm- (CG) based FWI, the energy distribution of the gradient calculated with the adjoint state ...
Jianbo Guan, Yu Li, Guohua Liu
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Fast Methods for Solving High Accuracy Surface Modeling
Journal of Algorithms & Computational Technology, 2013 High accuracy surface modeling (HASM) is a novel surface modeling method. The well known preconditioned conjugate gradient (PCG) method is used to solve the equations produced by HASM.
Na Zhao, Tian Xiang Yue
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Research of the Algebraic Multigrid Method for Electron Optical Simulator
Entropy, 2022 At present, electron optical simulator (EOS) takes a long time to solve linear FEM systems. The algebraic multigrid preconditioned conjugate gradient (AMGPCG) method can improve the efficiency of solving systems.
Zhi Wang +7 more
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Super-resolution using preconditioned conjugate gradient method [PDF]
SPIE Proceedings, 2002 In this paper we present a fast iterative image superresolution algorithm using preconditioned conjugate gradient method. To avoid explicitly computing the tolerance in the inverse filter based preconditioner scheme,1 a new Wiener filter based preconditioner for the conjugate gradient method is proposed to speed up the convergence.
Changjiang Yang +2 more
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Results in Applied Mathematics, 2019 An improved preconditioned conjugate gradient squared (PCGS) algorithm has recently been proposed, and it performs much better than the conventional PCGS algorithm.
Shoji Itoh, Masaaki Sugihara
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Conjugate gradient type methods and preconditioning
Journal of Computational and Applied Mathematics, 1988 The properties of various iterative methods for the numerical solution of very large, sparse linear systems of equations are reviewed in order to assist the user in making a deliberate selection. Tables that help to make a choice in iterative methods and preconditionings for certain types of problems are presented.
Van der Vorst, Henk A., Dekker, Kees
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