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comments on ASS

From: Guus Schreiber <schreiber@swi.psy.uva.nl>
Date: Sun, 12 Jan 2003 17:22:37 +0000
Message-ID: <3E21A45D.60607@swi.psy.uva.nl>
To: www-webont-wg@w3.org

During the delays on the way home from the ftf I had some time for 
additional reviewing of the ASS document, also in relation to GUIDE and 
REF.

I have top main comments. The first point relates to the OWL Lite 
production for class axioms, which reads (BTW thanks for the great 
cross-ref table!) :

axiom ::= 'Class(' classID modality { annotation } { super } ')'
modality ::= 'complete' | 'partial'
super ::= classID | restriction

axiom ::= 'EquivalentClasses(' classID { classID } ')'

I thought we had no defined classes in OWL Lite, so shouldn't the 
modality always be "partial"? As it is, the production allows a 
sameClassAs statement between a class and a restriction, which Guide 
expliclty labels as being an OWL DL construction (see the TexasThings 
example).

The second comment came up when I was revising the Reference document 
section on classes. In the Guide we see RDF/XML class axioms such as:

<owl:Class rdf:ID="WhiteWine">
   <owl:intersectionOf rdf:parseType="Collection">
     <owl:Class rdf:about="#Wine" />
     <owl:Restriction>
       <owl:onProperty rdf:resource="#hasColor" />
       <owl:hasValue rdf:resource="#White" />
     </owl:Restriction>
   </owl:intersectionOf>
</owl:Class>

As I understand it the abstract syntax only allows axioms
of the form:
   <description> <relation> <description>
where <description> should be a class name, a restriction or any of the 
set-operation constructs, and <relation> should be subClassOf, 
sameClassAs, or dinjointWith.

I had alsways thought the Guide examples where a shorthand with an 
implicit sameClassAs statement, but this does not seem to be covered by 
the ASS document. Did I miss something (not at all unlikely)?

A final comment about the presentation: the ASS document often uses the 
term OWL/DL, where it actually means OWL/DL and OWL/Full.
Please make this clear. The difference is only valid for the semantics 
sections. BTW: the asbtract should also mention OWL/Full.

Guus

- mention OWL Full in the abstract.
- use  "OWL" or OWL DL/Full in cases where yo
Received on Sunday, 12 January 2003 12:22:39 GMT

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