TY - JOUR A1 - Krebs, Andreas A1 - Stephan, Ernst P. T1 - A p-version finite element method for nonlinear elliptic variational inequalities in 2D N2 - This article introduces and analyzes a p-version FEM for variational inequalities resulting from obstacle problems for some quasi-linear elliptic partial differential operators. We approximate the solution by controlling the obstacle condition in images of the Gauss-Lobatto points. We show existence and uniqueness for the discrete solution u p from the p-version for the obstacle problem. We prove the convergence of u p towards the solution with respect to the energy norm, and assuming some additional regularity for the solution we derive an a priori error estimate. In numerical experiments the p-version turns out to be superior to the h-version concerning the convergence rate and the number of unknowns needed to achieve a certain exactness of the approximation. KW - FEM Y1 - 2007 UR - https://opus4.kobv.de/opus4-UBICO/frontdoor/index/index/docId/3569 UR - http://www.springerlink.com/content/p1126727200545k8/fulltext.pdf ER -