X-Protege: An Ontology Editor for Defining Cartesian Types to Represent n-ary Relations.

Christian Willms, Hans-Ulrich Krieger, Bernd Kiefer

In: Joint Second Workshop on Language and Ontology & Terminology and Knowledge Structures. Workshop on Language and Ontology (LangOnto-2016) befindet sich 10th edition of the Language Resources and Evaluation Conference, 2016 May 23-28 Portoroz Slovenia ELDA 5/2016.


Arbitrary n-ary relations (n >= 1) can, in principle, be realized through binary relations obtained by a reification process which introduces new individuals to which the additional arguments are linked via ``accessor'' properties. Modern ontologies which employ standards such as RDF and OWL have mostly obeyed this restriction, but have struggled with it nevertheless. In Krieger & Willms (2015), we have laid the foundations for a theory-agnostic extension of RDFS and OWL and have implemented in the last year an extension of Protege, called X-Protege, which supports the definition of Cartesian types to represent n-ary relations and relation instances. Not only do we keep the distinction between the domain and the range of an n-ary relation, but also introduce so-called extra arguments which can be seen as position-oriented unnamed annotation properties and which are accessible to entailment rules. As the direct representation of n-ary relations abolishes RDF triples, we have backed up X-Protege by the semantic repository and entailment engine HFC which supports tuples of arbitrary length. X-Protege is programmed in Java and is made available under the Mozilla Public License.


xprotege.pdf (pdf, 227 KB )

Deutsches Forschungszentrum für Künstliche Intelligenz
German Research Center for Artificial Intelligence