We study containment and equivalence of (unions of) conjunctive queries on relations annotated with elements of a commutative semiring. Such relations and the semantics of positiv...
We present cq-programs, which enhance nonmonotonic description logics (dl-) programs by conjunctive queries (CQ) and union of conjunctive queries (UCQ) over Description Logics kno...
Thomas Eiter, Giovambattista Ianni, Thomas Krennwa...
We study the expressiveness of a positive fragment of path queries, denoted Path+ , on node-labeled trees documents. The expressiveness of Path+ is studied from two angles. First, ...
Yuqing Wu, Dirk Van Gucht, Marc Gyssens, Jan Pared...
The problem of answering SPARQL queries over virtual SPARQL views is commonly encountered in a number of settings, including while enforcing security policies to access RDF data, ...
Wangchao Le, Songyun Duan, Anastasios Kementsietsi...
Abstract. It is well-knwon that crisp RDF is not suitable to represent vague information. Fuzzy RDF variants are emerging to overcome to this limitations. In this work we provide, ...