Results 21 to 30 of about 625 (264)
Rational Approximations in Robust Preconditioning of Multiphysics Problems
Mathematics, 2022 Multiphysics or multiscale problems naturally involve coupling at interfaces which are manifolds of lower dimensions. The block-diagonal preconditioning of the related saddle-point systems is among the most efficient approaches for numerically solving ...
Stanislav Harizanov +2 more
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A Preconditioner for the Ohta--Kawasaki Equation [PDF]
SIAM Journal on Matrix Analysis and Applications, 2017 We propose a new preconditioner for the Ohta--Kawasaki equation, a nonlocal Cahn--Hilliard equation that describes the evolution of diblock copolymer melts. We devise a computable approximation to the inverse of the Schur complement of the coupled second-order formulation via a matching strategy.
Farrell, Patrick E., Pearson, John
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On the Construction of Deflation-Based Preconditioners [PDF]
SIAM Journal on Scientific Computing, 2001 New effective condition number bounds for deflated systems, both with and without preconditioning are given. Subdomain deflation is very easy to implement, and the method can be very efficiently implemented on distributed memory parallel computers. Numerical experiments for a steady-state are included.
J.E. Frank (Jason), C. Vuik
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Preconditioning GMRES for discontinuous Galerkin approximations
Computer Assisted Methods in Engineering and Science, 2023 The paper presents an implementation and the performance of several preconditioners for the discontinuous Galerkin approximation of diffusion dominated and pure diffusion problems.
Krzysztof Banaś, Mary F. Wheeler
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A new approximate inverse preconditioner based on the Vaidya’s maximum spanning tree for matrix equation AXB = C [PDF]
Iranian Journal of Numerical Analysis and Optimization, 2019 We propose a new preconditioned global conjugate gradient (PGL-CG) method for the solution of matrix equation AXB = C, where A and B are sparse Stieltjes matrices. The preconditioner is based on the support graph preconditioners.
K. Rezaei, F. Rahbarnia, F. Toutounian
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A Preconditioner for Improved Fermion Actions [PDF]
Nuclear Physics B - Proceedings Supplements, 1999 SSOR preconditioning of fermion matrix inversions which is parallelized using a locally-lexicographic lattice sub-division, has been shown to be very efficient for standard Wilson fermions. We demonstrate here the power of this method for the Sheikholeslami-Wohlert improved fermion action and for a renormalization group improved action incorporating ...
Wolfgang Bietenholz +5 more
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Axioms, 2018 This work studies limited memory preconditioners for linear symmetric positive definite systems of equations. Connections are established between a partial Cholesky factorization from the literature and a variant of Quasi-Newton type preconditioners ...
Benedetta Morini
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Circulant preconditioners for mean curvature-based image deblurring problem
Journal of Algorithms & Computational Technology, 2021 The mean curvature-based image deblurring model is widely used to enhance the quality of the deblurred images. However, the discretization of the associated Euler–Lagrange equations produces a nonlinear ill-conditioned system which affects the ...
Shahbaz Ahmad, Faisal Fairag
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Nuclear Engineering and Technology, 2022 In this paper, a new multi-group neutron-gamma transport calculation code system STRAUM-MATXST for complicated geometrical problems is introduced and its development status including numerical tests is presented.
MyeongHyeon Woo, Ser Gi Hong
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Communication Avoiding ILU0 Preconditioner [PDF]
SIAM Journal on Scientific Computing, 2015 Summary: In this paper we present a communication avoiding ILU0 preconditioner for solving large linear systems of equations by using iterative Krylov subspace methods. Recent research has focused on communication avoiding Krylov subspace methods based on so-called \(s\)-step methods.
Grigori, Laura, Moufawad, Sophie
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