OWL Shows Off

Re: Does Euler support owl:hasValue ? from Jos De_Roo on 2004-04-14 (www-rdf-logic@w3.org from April 2004)

I was very lucky to get help from Bejamin Nowack and Mr. Euler Jos De Roo. I asked the www-rdf-logic list about how to declare an object is a member of a owl:Class based on a Literal value of a Property. I was close, only backwards. The correct OWL would be something like:


[ a owl:Restriction ; owl:onProperty dc:subject ; owl:hasValue "blogging"^^xsd:string ] rdfs:subClassOf :PostAboutBlogging .
:PostAboutBlogging a owl:Class .
dc:subject a owl:DatatypeProperty ; rdfs:range xsd:string .


Then, with a fact like the following (easily taken from some RSS):


:blogitem a owl:Thing ; dc:subject "blogging"^^xsd:string .


I could tell:


:blogitem a :PostAboutBlogging .


I hope this at least illustrates my goal: to map different dc:subjects from different blogs into a locally understood set of owl:Classes. Then, provide a way to create Planet*.com sites with ad hoc aggregation based on queries given by users. And the first query: " Collect all blog entries that are of type XXX "

OWL is nice, and Euler is nice. Now, to plug them into the planetrdf.com code.

Thoughts or comments?

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