Annotating photos with events/subevents

Hi everyone.

I'm making a photo database using Jena, and I've decided to describe
what event a photo belongs to by using foaf:topic--actually, an
rdfs:subPropertyOf foaf:topic that I've called photo:event.  I want to
expose the RDF in my database for aggregation purposes.

My events will be arranged into a hierarchy where an event can be a
subevent of another event.  For example:

  <> a photo:Event ;
  	rdfs:label "Tokyo 2004" .

  <> a photo:Event ;
  	rdfs:label "SVG Open 2004" ;
	photo:subEventOf <> .

  <> a foaf:Image ;
  	dc:title "Conference registration" ;
	photo:event <> .

I want it to be the case that

    if A photo:event B
   and B photo:subEventOf C
  then A photo:event C.

I don't want to have to explicitly say that p1.jpg has a photo:event of
both SVGOpen and Tokyo.  Is there some way I can encode the above rule
in RDFS or OWL somehow?  I have a feeling that I can't, but thought I
would try anyway, in case I missed something.

If not, am I going about this problem the wrong way?  Would there be a
better way to model my photos in events?

Would the type of rules usable in cwm be the right way to encode it?
If other RDF processors don't understand these rules, though, this is
just the same problem as leaving the entailing semantics in photo:event,
isn't it?

Should I perhaps process the entailment of A photo:event C within my
Jena program, and always output the entailed photo:event statements?



Cameron McCormack
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Received on Tuesday, 2 November 2004 12:53:26 UTC