Modified block-approximate factorization strategies.
Multigrid method with preconditioning on coarse level
An algorithm for using the preconditioned conjugate gradient method to solve a coarse level problem is presented.
Multigrid preconditioning and Toeplitz matrices.
Multilevel preconditioners for Lagrange multipliers in domain imbedding.
Multilevel preconditioning.
Multilevel Schwarz methods.
Multiplicative Schwarz Methods for Discontinuous Galerkin Approximations of Elliptic Problems
In this paper we introduce and analyze some non-overlapping multiplicative Schwarz methods for discontinuous Galerkin (DG) approximations of elliptic problems. The construction of the Schwarz preconditioners is presented in a unified framework for a wide class of DG methods. For symmetric DG approximations we provide optimal convergence bounds for the corresponding error propagation operator, and we show that the resulting methods can be accelerated by using suitable Krylov space solvers. A discussion...