A regularized multi-level technique for solving potential problems by the method of fundamental solutions

Robust Superlinear Krylov Convergence for Complex Noncoercive Compact-Equivalent Operator Preconditioners

“…Further directions where the above results might be extended arise for boundary integral equations forming Fredholm equations of the second kind. For the method of fundamental solutions, it was found that the monopole and dipole formulations lead to matrices that approximate linear operators being compact perturbations of the identity [21,22]. For electric field integral equations on screens, compactequivalent preconditioning operators have been constructed in [32] as solution operators of variational problems set in low-regularity standard trace spaces.…”