We propose an a posteriori error estimator for high-order p- or hp-finite element discretizations of selfadjoint linear elliptic eigenvalue problems that is appropriate estimating the in approximation cluster and corresponding invariant subspace. The based on computation approximate functions space complements one which eigenvectors were computed. These are used to construct estimates collectiv...

Abstract. We derive pointwise a posteriori residual-based error estimates for finite element solutions to the Stokes equations in polyhedral domains. The estimates relies on the regularity of the of Stokes equations and provide an upper bound for the pointwise error in the velocity field on polyhedral domains. Whereas the estimates provide upper bounds for the pointwise error in the gradient of...

In this paper, we investigate a residual-based posteriori error estimates for the hp finite element approximation of general optimal control problems governed by bilinear elliptic equations. By using the hp discontinuous Galerkin finite element approximation for the control and the hp finite element approximation for both the state and the co-state, we derive a posteriori upper error bounds for...

We investigate an a posteriori error analysis of adaptive finite element approximations of linear-quadratic boundary optimal control problems under bilateral bound constraints, which act on a Neumann boundary condition. We use a symmetric interior penalty Galerkin (SIPG) method as discretization method. An efficient and reliable residual-type error estimator is introduced by invoking data oscil...