This the 28th issue of Transactions on Large-Scale Data- and Knowledge-Centered Systems
contains extended and revised versions of six papers presented at the 26th International
Conference on Database- and Expert-Systems Applications DEXA 2015 held in Valencia Spain in
September 2015. Topics covered include efficient graph processing machine learning on big data
multistore big data integration ontology matching and the optimization of histograms for the
Semantic Web.
