- From: Yuzhong Qu <yzqu@seu.edu.cn>
- Date: Fri, 25 Apr 2003 20:28:59 +0800
- To: "Guus Schreiber" <schreiber@cs.vu.nl>
- Cc: "webont-comments" <public-webont-comments@w3.org>
It's acceptable. Thanks for your clarification on rdf:resource and rdfs:Resource. Yuzhong Qu > Yuzhong Qu commented: > http://lists.w3.org/Archives/Public/public-webont-comments/2003Apr/0024.html > > > 1. The PRECISE SYNTAX of OWL > > > > [..] > > This comment was answered by Jeremy Carrol: > http://lists.w3.org/Archives/Public/public-webont-comments/2003Apr/0052.html > > > > 2. The domain and range of owl:equivalentClass in OWL Lite. > > > > [ 3.2.2 owl:equivalentClass > > ... > > NOTE: OWL DL does not put any constraints on the types of class > > descriptions that can be used as domain and range values of an > > owl:equivalentClass statement. In OWL Lite **only class > identifiers and > > property restrictions** are allowed as domain and range values. (?) > > > > 8.3 OWL Lite > > ... > > the subject of owl:equivalentClass triples be named classes and > > the object of owl:equivalentClass triples be named classes, > > restrictions, or subjects of owl:intersectionOf triples (?); > > ... > > ] > > > > 1) According to S&AS, the domain of owl:equivalentClass must be just > > classID. > > > > 2) As to the range of owl:equivalentClass, class identifiers and > > property restrictions are certainly allowed as range values. But how > > about others allowed as range values? What's "the subjects of > > owl:intersectionOf triples" mentioned in section 8.3? > > > > It seems most likely to be anonymous classes defined as the > > conjunctions of class identifiers and property restrictions. > > > > It (The domain and range of owl:equivalentClass in OWL Lite) should > > be explicitly and consistently specified. > > > > In OWL Lite the domain of owl:equivalentClass must be a named class > and the range must be be either a named class or a restriction.. > > We will delete the phrase "or subjects of owl:intersectionOf > triples" from the first bullet of the list in Sec. 8.3 of Reference. > > > > > 3. RDF schema for OWL (Appendix B) > > > > 1) "rdf:resource" is a typo error as I mentioned before. It should be > > "rdfs:Resource". > > "rdf:resource is written with a lowercase in constructions like: > > <rdf:Property rdf:ID="backwardCompatibleWith"> > <rdfs:label>backwardCompatibleWith</rdfs:label> > <rdfs:domain rdf:resource="#Ontology"/> > <rdfs:range rdf:resource="#Ontology"/> > </rdf:Property> > > It is in the RDF namespace, so it should really be "rdf:" > > > > 2) The definition of owl:Thing and owl:Nothing > > > > <Class rdf:ID="Thing"> > > <rdfs:label>Thing</rdfs:label> > > <unionOf rdf:parseType="Collection"> > > <Class rdf:about="#Nothing"/> > > <Class> > > <complementOf rdf:resource="#Nothing"/> > > </Class> > > </unionOf> > > </Class> > > > > <Class rdf:ID="Nothing"> > > <rdfs:label>Nothing</rdfs:label> > > <complementOf rdf:resource="#Thing"/> > > </Class> > > > > I suggest the axiom for owl:Thing be simplified as follows: > > <Class rdf:ID="Thing"> > > <rdfs:label>Thing</rdfs:label> > > </Class> > > > > Is there any lose of meaning? > > We think so. The class axiom for owl:Thing defines its class extension > to be the extension of owl:Nothing plus its complement, which means all > individuals in the universe of discourse. owl:Nothing is its complement, > so its class extension is the empty set. > > > > > I note owl:Nothing is not included in OWL Lite. [A note in section > > 3.1 Class descriptions]. > > > > Including owl:Nothing in OWL Lite will bring any harmness to OWL Lite ? > > This comment will be answered in the context of your comments on OWL > S&AS, see Peter Patel-Schneider's message: > http://lists.w3.org/Archives/Public/public-webont-comments/2003Apr/0043.html > > > > > 4. The rdfs:range of owl:imports > > > > In Appendix C (OWL Quick Reference), the rdfs:range of owl:imports is > > missing. It should be owl:Ontology (according to Appendix B). > > > > Thanks for spotting this. We will make the appropriate editorial change > to Appendix C. > > > > > > Yuzhong Qu > > > Please can you reply to this message on the public-webont-comments@w3.org > list, indicating whether we should be giving further consideration to your > comment or whether these pointers have adequately clarified the situation. > > Thanks again very much for your comments. > > Regards, Guus Schreiber > > -- > NOTE: new affiliation per April 1, 2003 > > Free University Amsterdam, Computer Science > De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands > Tel: +31 20 444 7739/7718 > E-mail: schreiber@cs.vu.nl > Home page: http://www.cs.vu.nl/~guus/ [under construction] > > >
Received on Friday, 25 April 2003 08:28:22 UTC