97 citations · 381 across the 25 of their papers we have counts for
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A finite element method for elliptic Dirichlet boundary control problems
Michael Karkulik
We consider the finite element discretization of an optimal Dirichlet boundary control problem for the Laplacian, where the control is considered in . To avoid computin…
Stable decompositions of -BEM spaces and an optimal Schwarz preconditioner for the hypersingular integral operator in 3D
Michael Karkulik, Jens Markus Melenk, Alexander Rieder
We consider fractional Sobolev spaces , , on a 2D surface . We show that functions in can be decomposed into contributions with local support in a s…
-matrix approximability of inverses of discretizations of the fractional Laplacian
Michael Karkulik, Jens Markus Melenk
The integral version of the fractional Laplacian on a bounded domain is discretized by a Galerkin approximation based on piecewise linear functions on a quasi-uniform mesh. We show…
New a priori analysis of first-order system least-squares finite element methods for parabolic problems
Thomas Führer, Michael Karkulik
We provide new insights into the a priori theory for a time-stepping scheme based on least-squares finite element methods for parabolic first-order systems. The elliptic part of th…