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Mapping cultural metadata schemas to CIDOC conceptual reference model
(2010)
Managing heterogeneous data is a challenge for cultural heritage institutions as they host and develop various collections with heterogeneous types of material, described by different metadata schemas. In this paper, we ...
A value-propagating transformation technique for Datalog programs based on non-deterministic constructs
(2006)
The branching-time transformation is a recent technique for optimizing Chain Datalog programs. In this paper we propose a significant extension of the branching-time transformation which we believe opens up a promising new ...
Representing and querying histories of semistructured databases using multidimensional OEM
(2004)
Multidimensional semistructured data (MSSD) are semistructured data that present different facets under different contexts. Context represents alternative worlds, and is expressed by assigning values to a set of user-defined ...
On rewriting Xpath Queries Using Views
(2009)
The problem of rewriting a query using a materialized view is studied for a well known fragment of XPath that includes the following three constructs: wildcards, descendant edges and branches. In earlier work, determining ...
Unfold/fold transformations for disjunctive logic programs
(1997)
Unfold/fold transformation rules for disjunctive logic programs are proposed in this paper. Our transformation rules preserve the meaning of the programs.
Union rewritings for XPath fragments
(2011)
In this paper, we study the problem of finding an equivalent rewriting of an XPath query using multiple views, and we show that the union operator may be required in order to find such a rewriting. In particular, focusing ...
Temporal stratification tests for linear and branching-time deductive databases
(2005)
We consider the problem of extending temporal deductive databases with stratified negation. We argue that the classical stratification test for deductive databases is too restrictive when one shifts attention to the temporal ...
Query containment under bag and bag-set semantics
(2010)
Conjunctive queries (CQs) are at the core of query languages encountered in many logic-based research fields such as AI, or database systems. The majority of existing work assumes set semantics but often in real applications ...
Incorporating dimensions in XML and DTD
(2001)
In this,paper we investigate various aspects of representing multidimensional information in the frame of the WWW. Multidimensional XML (MXML) is an extension of XML suitable for representing data that assume different ...
Interoperability Between Archival and Bibliographic Metadata: an EAD to MODS Crosswalk
(2009)
In this article we investigate the problem of semantic interoperability between archival and bibliographic metadata used in digital libraries and repositories. We investigate the semantic relationships between two metadata ...