Re: LANG?/SEM?: using resources

At 11:18 AM -0400 9/18/02, Peter F. Patel-Schneider wrote:
>From: Jim Hendler <hendler@cs.umd.edu>
>Subject: Re: LANG?/SEM?: using resources (was Re: LANG: owl:ontology)
>Date: Wed, 18 Sep 2002 11:06:40 -0400
>
>>  >
>>  >
>>  >
>>  >As far as I can see the only viable route is to be able to use resources
>>  >without committing to anything related to that resource.  To commit to
>>  >something in some other ontology/document, use imports.
>>  >
>>
>>  If I understand what he said correctly, Peter and I are in complete
>>  agreement.  [...]
>>    -JH

I take it back, I guess I may not have understood what Peter said...

>
>Well, perhaps, but what then was the point of your example?  Wouldn't it
>have been simpler, and much less confusing, to have said
>
>[snip]



>  > This is the case I really care about.  For imports anything that can
>>  identify and merge graphs makes me happy - for this case, I care that
>>  we somehow scope what is included.  I would like [URI2 to not include any
>>  information from URI1].
>
>
>I took the whole point of your example to be that *something* was
>transferred from URI1 to URI2.

I don't want nothing transferred, I want only the ones I explicitely 
mention to be included in the new graph.  I'm still not clear whether 
this is or is not what you mean (and why I'm confused).


Let me be as specific as possible and please tell me what is included 
in the graph:

URI1 contains the following class definition

<rdfs:Class rdf:ID="Break">
   <rdfs:subClassOf   URI2:agendaitem>
   <rdfs:subClassOf>
     <daml:Restriction>
       <daml:onProperty rdf:resource="#start"/>
       <daml:toClass 
rdf:resource="http://www.w3.org/2000/10/XMLSchema#timeInstant"/>
     </daml:Restriction>
   </rdfs:subClassOf>
</rdfs:Class>

URI2 contains the following class definitions:

<rdfs:Class rdf:ID="AgendaItem">
</rdfs:Class>


<rdfs:Class rdf:ID="Topic">
   <rdfs:subClassOf rdf:resource="#AgendaItem"/>
   </rdfs:subClassOf>
</rdfs:Class>


What I expect is that URI1 will entail that Break is in a subclass 
relation to AgendaItem, but not that Topic is in a subclass relation 
with AgendaItem.

What I am less clear on (and could go either way) is if instead URI2 said:

<rdfs:Class rdf:ID="AgendaItem">
   <rdfs:subClassOf>
     <daml:Restriction>
       <daml:onProperty rdf:resource="#uri"/>
       <daml:toClass 
rdf:resource="http://www.w3.org/2000/10/XMLSchema#uriReference"/>
     </daml:Restriction>
</rdfs:Class>

whether this means that if Break has a uri resource it must be a 
uriReference (or however you want to ensure that the #uri 
field-related triples are included), but I would still expect Break 
to be a subclassOf agendaItem.


Perhaps this simple (and real) example will help.
  -JH

-- 
Professor James Hendler				  hendler@cs.umd.edu
Director, Semantic Web and Agent Technologies	  301-405-2696
Maryland Information and Network Dynamics Lab.	  301-405-6707 (Fax)
Univ of Maryland, College Park, MD 20742	  240-731-3822 (Cell)
http://www.cs.umd.edu/users/hendler