@misc{Yserentant, author = {Yserentant, Harry}, title = {Two Preconditioners Based on the Multi-Level Splitting of Finite Element Spaces.}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-274}, number = {SC-89-09}, abstract = {The hierarchical basis preconditioner and the recent preconditioner of BRAMBLE, PASCIAK and XU are derived and analyzed within a joint framework. This discussion elucidates the close relationship between both methods. Special care is devoted to highly nonuniform meshes; our theory is based exclusively on local properties like the shape regularity of the finite elements.}, language = {en} }