Error estimation with guaranteed accuracy of finite element method in nonconvex polygonal domains.
The aim of the paper is to estimate errors of the finite element method for a nonconvex polygonal domain. This work extends the results of \textit{N. Yamamoto} and \textit{M. T. Nakao} [ Numer. Math. 65, 503--521 (1993; Zbl 0797.65081)]. The authors derive an upper bounds for the errors using calculations with guaranteed accuracy. Several numerical examples are presented and their convergence orders are compared with the theoretical ones.
scientific article; zbMATH DE number 1993211