- From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Date: Sun, 09 Dec 2007 08:19:32 -0500 (EST)
- To: alanruttenberg@gmail.com
- Cc: ian.horrocks@comlab.ox.ac.uk, public-owl-wg@w3.org
Yes indeed. peter From: Alan Ruttenberg <alanruttenberg@gmail.com> Subject: Re: QCR problem in OWL 1.1 Full - action ?? from F2F Date: Sat, 8 Dec 2007 05:13:33 +0000 > Can this be fixed by using a different property than > owl:maxCardinality? e.g. > > _:y rdf:type owl:Restriction > _:y owl:maxQualifiedCardinality "2"^^xsd:nonNegativeInteger > _:y owl:onProperty child > _:y owl11:onClass Person > > i.e. s/owl:maxCardinality/owl:maxQualifiedCardinality/ > > -Alan > > On Dec 7, 2007, at 2:23 PM, Peter F. Patel-Schneider wrote: > > > Qualified Cardinalities in OWL 1.1 Full > > > > > > Suppose that we want to keep the general flavour of the OWL Full > > semantics *and* use the current OWL 1.1 mapping to RDF. What would > > happen? > > > > > > Here is an example of how the RDF mapping works (roughly). > > > > ObjectMaxCardinality(2 child) expands to: > > > > _:x rdf:type owl:Restriction > > _:x owl:maxCardinality "2"^^xsd:nonNegativeInteger > > _:x owl:onProperty child > > > > ObjectMaxCardinality(2 child Person) expands to: > > > > _:y rdf:type owl:Restriction > > _:y owl:maxCardinality "2"^^xsd:nonNegativeInteger > > _:y owl:onProperty child > > _:y owl11:onClass Person > > > > Note especially that the first set of triples is a "subset" of the > > second set. > > > > > > The OWL 1.0 Full semantics says that the class extension of _:x is the > > set of objects that are related to at most two objects via the > > property > > extension of child. A similar-style OWL 1.1 Full semantics would say > > that the class extension of _:y is the set of objects that are related > > to at most two objects that belong to the class extension of Person > > via > > the property extension of child. > > > > However, the OWL 1.1 Full semantics would then also include the OWL > > 1.0 > > Full semantics. So, part of the meaning of the last four triples > > (actually the first three of these four, but that doesn't matter) > > in OWL > > 1.1 Full would be that the class extension of _:y would *as well* > > be the > > set of objects that are related to at most 2 objects via the property > > extension of child. > > > > So, if o is in the class extension of _:y then it is related to at > > most > > two objects that belong to the class extension of Person via the > > property extension of child *and* it is related to at most two objects > > via the property extension of child. It is impossible to have a > > max-QCR > > without this double meaning. > > > > > > > > peter > > >
Received on Sunday, 9 December 2007 13:38:42 UTC