A-POSTERIORI LOCAL ERROR-ESTIMATES OF BOUNDARY ELEMENT METHODS WITH SOME PSEUDODIFFERENTIAL-EQUATIONS ON CLOSED CURVES

In this paper we show local error estimates for the Galerkin finite element method applied to strongly elliptic pseudo-differential equations on closed curves. In these local estimates the right hand sides are obtained as the sum of a local norm of the residual, which is computable, and additional terms of higher order with respect to the meshwidth. Hence, asymptotically, here the residual is an error indicator which provides a corresponding self-adaptive boundary element method.