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Re: Moving forward

From: Jos De_Roo <jos.deroo.jd@belgium.agfa.com>
Date: Tue, 19 Mar 2002 15:35:58 +0100
To: jonathan@openhealth.org
Cc: www-webont-wg@w3.org
Message-ID: <OF332B48CA.D7D10286-ONC1256B81.004831E0@agfa.be>

Jonathan,
>
>> as an aside, I have some trouble that
>>   :John a :Person .
>>   :John a :Student .
>>
>> would entail
>>   :John a [ owl:intersectionOf ( :Person :Student ) ] .
>>
>> but no trouble that it would entail
>>   :John a ( owl:intersectionOf ( :Person :Student ) ) .
>>
>
>What does this mean? (For those of us who are both N3  and semantically
>challenged)

not having the required experience for that, I'll try to give
an indication based on what I learned from Pat&Peter so I think it
is better to first have a look at http://www.w3.org/TR/rdf-mt/

first of all assume following facts (written as RDF triples)

------------------------------------------------------------------------
owl:intersectionOf ardf:type rdf:Property .
owl:intersectionOf rdfs:domain owl:Class .
owl:intersectionOf rdfs:range owl:List .
------------------------------------------------------------------------
owl:List rdfs:subClassOf rdfs:Class .    # @@@@@ need much more thought
------------------------------------------------------------------------

and then assume following derivations (part of OWL-entailment)

------------------------------------------------------------------------
IF you have that               | THEN you can conclude
------------------------------------------------------------------------
?x a ?a                        | ?x a ( owl:intersectionOf ( ?a ) )
------------------------------------------------------------------------
?x a ?a                        | ?x a ( owl:intersectionOf ( ?a / ?b ) )
?x a ( owl:intersectionOf ?b ) |
------------------------------------------------------------------------
?x a ( owl:intersectionOf ?L ) | ?x a ?C
?L owl:item ?C                 |
------------------------------------------------------------------------

the last for for instance says that: if ?x is belonging to the
intersection of the classes given in list ?L and if class ?C is
a member of ?L then we can conclude that ?x is of rdf:type ?C

--
Jos
Received on Tuesday, 19 March 2002 09:36:36 GMT

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