From: Jeremy Carroll <jjc@hpl.hp.com>

Date: Fri, 06 Sep 2002 15:08:04 +0200

To: Ian Horrocks <horrocks@cs.man.ac.uk>

Cc: www-webont-wg@w3.org

Message-id: <BHEGLCKMOHGLGNOKPGHDKEALCAAA.jjc@hpl.hp.com>

Date: Fri, 06 Sep 2002 15:08:04 +0200

To: Ian Horrocks <horrocks@cs.man.ac.uk>

Cc: www-webont-wg@w3.org

Message-id: <BHEGLCKMOHGLGNOKPGHDKEALCAAA.jjc@hpl.hp.com>

> Given a sufficiently expressive language (i.e., one like OWL), this > doesn't represent any restriction w.r.t. what you ask for below, i.e., > being able to determine if ontology O1 models ontology O2. This is > trivially reducible to ontology consistency. IIUC only if you can negate an Ontology. not(prop rdf:type owl:TransitiveProperty ) is not in OWL. > Similarly > for a DL, the frame axioms might state that there is a subset of the > set of all property names (the transitive properties) whose > interpretations must be transitively closed. In terms of Pat's document then If E is: owl:TransitiveProperty then x is in ICEXT(I(E)) iff: <y, z> and <z, u> in IEXT(x) implies <y, u> in IEXT(x) should be weakened to If E is: owl:TransitiveProperty then [[ x is in ICEXT(I(E)) implies { <y, z> and <z, u> in IEXT(x) implies <y, u> in IEXT(x) } ]] I still haven't understood which way you prefer to go on this. Sorry. (I found your message quite difficult :( ). e.g. >Having said that, the expressive power of OWL means that entailment >w.r.t. ontologies containing property inclusion and transitivity >axioms is still trivially reducible to ontology consistency. Could you please give an example: e.g. { empty } does not entail { foo rdf:type owl:TransitiveProperty } how do I convert that into a consistency question? JeremyReceived on Friday, 6 September 2002 09:08:22 UTC

*
This archive was generated by hypermail 2.3.1
: Tuesday, 6 January 2015 21:56:47 UTC
*