Results 1 to 10 of about 54,023 (335)
A Bramble-Pasciak conjugate gradient method for discrete Stokes equations with random viscosity
, 2018 We study the iterative solution of linear systems of equations arising from stochastic Galerkin finite element discretizations of saddle point problems. We focus on the Stokes model with random data parametrized by uniformly distributed random variables ...
Lang, Jens +2 more
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A theory of secant preconditioners [PDF]
Mathematics of Computation, 1993 In this paper we analyze the use of structured quasi-Newton formulae as preconditioners of iterative linear methods when the inexact-Newton approach is employed for solving nonlinear systems of equations. We prove that superlinear convergence and bounded work per iteration is obtained if the preconditioners satisfy a Dennis-Moré condition. We develop a
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On Comparison Theorems for Splittings of Different Semimonotone Matrices
Journal of Applied Mathematics, 2014 Comparison theorems between the spectral radii of different matrices are useful tools for judging the efficiency of preconditioners. In this paper, some comparison theorems for the spectral radii of matrices arising from proper splittings of different ...
Shu-Xin Miao, Yang Cao
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Combined Preconditioning with Applications in Reservoir Simulation
, 2013 We develop a simple algorithmic framework to solve large-scale symmetric positive definite linear systems. At its core, the framework relies on two components: (1) a norm-convergent iterative method (i.e. smoother) and (2) a preconditioner. The resulting
Hu, Xiaozhe +6 more
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Preconditioned iterative methods for Navier-Stokes control problems [PDF]
, 2013 PDE-constrained optimization problems are a class of problems which have attracted much recent attention in scientific computing and applied science. In this paper, we discuss preconditioned iterative methods for a class of Navier-Stokes control problems,
Pearson, John W.
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, 2018 We present optimal preconditioners for a recently introduced hybridized discontinuous Galerkin finite element discretization of the Stokes equations.
Rhebergen, Sander, Wells, Garth N.
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Robust Block Preconditioners for Biot’s Model [PDF]
, 2018 submitted
Adler, J.H. +4 more
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Improved New Block Preconditioner for Solving 3 × 3 Block Saddle Point Problems
AxiomsIn order to overcome the computational challenges associated with block preconditioners for Krylov subspace methods, particularly those arising from Schur complement systems, this paper proposes an improved new block (INB) preconditioner for solving 3 ...
Xin-Hui Shao, Xin-Yang Liu
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Mathematical and Computational Applications, 2019 In nuclear engineering, the λ -modes associated with the neutron diffusion equation are applied to study the criticality of reactors and to develop modal methods for the transient analysis. The differential eigenvalue problem that needs to be
Amanda Carreño +5 more
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Preconditioners for state constrained optimal control problems\ud with Moreau-Yosida penalty function tube [PDF]
, 2010 Optimal control problems with partial differential equations play an important role in many applications. The inclusion of bound constraints for the state poses a significant challenge for optimization methods.
Stoll, M., Wathen, A. J.
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