caa a22 4500 378860232 CHVBK 20180305123344.0 cr unu---uuuuu 161128s2003 xx s 000 0 eng 10.2478/cmam-2003-0014 doi (NATIONALLICENCE)gruyter-10.2478/cmam-2003-0014 Singular Function Mortar Finite Element Methods [Elektronische Daten] We consider the Poisson equation with Dirichlet boundary conditions on a polygonal domain with one reentrant corner. We introduce new nonconforming finite element discretizations based on mortar techniques and singular functions. The main idea introduced in this paper is the replacement of cut-off functions by mortar element techniques on the boundary of the domain. As advantages, the new discretizations do not require costly numerical integrations and have smaller a priori error estimates and condition numbers. Based on such an approach, we prove optimal accuracy error bounds for the discrete solution. Based on such techniques, we also derive new extraction formulas for the stress intensive factor. We establish optimal accuracy for the computed stress intensive factor. Numerical examples are presented to support our theory. This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. mortar elements nationallicence corner singularity nationallicence nonconforming finite element nationallicence Sarkis Marcus Instituto de Matem´atica Pura e Aplicada, Est. Dona Castorina, 110, Rio de Janeiro, RJ, CEP 22420-320, Brazil. Mathematical Sciences Department, Worcester Polytechnic Institute, 100 Institute Rd, Worcester, MA 01619. Tu Xuemin Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012. Computational Methods in Applied Mathematics De Gruyter 3/1(2003), 202-218 1609-4840 3:1<202 2003 3 cmam https://doi.org/10.2478/cmam-2003-0014 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.2478/cmam-2003-0014 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sarkis Marcus Instituto de Matem´atica Pura e Aplicada, Est. Dona Castorina, 110, Rio de Janeiro, RJ, CEP 22420-320, Brazil. Mathematical Sciences Department, Worcester Polytechnic Institute, 100 Institute Rd, Worcester, MA 01619 NATIONALLICENCE 700 1- Tu Xuemin Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012 NATIONALLICENCE 773 0- Computational Methods in Applied Mathematics De Gruyter 3/1(2003), 202-218 1609-4840 3:1<202 2003 3 cmam CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter