Document-centric XML collections contain text-rich documents, marked up with XML tags. The tags add lightweight semantics to the text. Querying such collections calls for a hybrid...
Preference queries are relational algebra or SQL queries that contain occurrences of the winnow operator (find the most preferred tuples in a given relation). Such queries are pa...
Van Emden's incremental queries address the inadequacy of current Prolog-style querying mechanism in most logic programming systems for interactive problem-solving. In the co...
In this paper, we present an extension of the scheme HH(C) (Hereditary Harrop formulas with Constraints) with a suitable formulation of negation in order to obtain a constraint ded...
A distributed calculus is proposed for describing networks of services. We model service interaction through a call-by-property invocation mechanism, by specifying the security co...
Massimo Bartoletti, Pierpaolo Degano, Gian Luigi F...