[Ontology] UCDs vs ontologies?

[Tony Linde]

No-one will even attempt to stop the DM group from discussing whatever they
wish. But the Semantics IG has been resurrected since *general* discussions
about this topic have surfaced on the UCD and DM list recently and
frequently come up in the Registry group.

Semantics IG will permit these discussions to be carried on without the very
annoying habit of cross-posting. The IGs are about discussions on how topics
are addressed in the IVOA, external work that might be made use of in the
IVOA, and what ideas are ready to be handed over to the workgroups for
action. The workgroups are more about getting standards defined.

Within the Semantics IG list (semantics at ivoa.net), we are even now
discussing the charter for the group. Please feel free to contribute so that
it is clearly spelled out how concepts and ideas raised there can be fed
into the DM workgroup.

T.

> -----Original Message-----
> From: owner-dm at eso.org [mailto:owner-dm at eso.org] On Behalf Of 
> Brian Thomas
> Sent: 02 June 2005 16:09
> To: dm at ivoa.net
> Subject: Re: [Ontology] UCDs vs ontologies?
> 
> On Thursday 02 June 2005 10:34 am, Ed Shaya wrote:
> > Are these discussions going to be on dm or semantics?  We 
> had better 
> > decide fast.  I had spoken with Jonathan just a few days ago and he 
> > felt this logically belonged inside of dm.  I agreed with 
> him because 
> > Ontology should be a basic component (an early stage) of 
> data modeling.
> > But then Tony Linde reminded me that there already is a 
> semantics site 
> > and that is where it belongs.  That makes sense too.  What 
> do others think?
> 
> 	As 'painfull' as it might be to suggest it, I vote for 
> the DM list (with proper
> 	subject line, of course, so it may be ignored). 
> Semantics are critical for 
> 	proper design of data models. 
> 
> 	=b.t.
> 
> > 
> > Ed
> > 
> > 
> > 
> > Sebastien Derriere wrote:
> > 
> > >[posted to dm only to avoid cross-posting]
> > >
> > >Elizabeth Auden wrote:
> > >  
> > >
> > >>Incidentally, I've posted a first go at a VOEvent 
> ontology (OWL-DL 
> > >>format) on the VOTech wiki at 
> > >>http://wiki.eurovotech.org/bin/view/VOTech/VoEventOntology. Any 
> > >>comments on the structure, concepts, and coverage of this 
> > >>v0.000000001 ontology would be appreciated.
> > >>    
> > >>
> > >
> > >  Hi,
> > >
> > >  Reading the questions you list in the above page, I have 
> a comment 
> > >on points 2 and 3.
> > >  When trying to build small ontologies, I found (and 
> still do find) 
> > >extremely stupid to be "forced" to define one slot 
> dedicated to each 
> > >class to indicate "hasSomething".
> > >  In your example, Contact / hasContact , How / hasHow, What / 
> > >hasWhat, ....
> > >I found this (and this is the case in every example I 
> could find) awful.
> > >
> > >  I wish we could define something where we don't have to be 
> > >omniscients when building the ontology, but where the 
> ability to make 
> > >reasonning would not be lost. Something like:
> > >  - Having a class named Property
> > >  - Having classes Contact, How, What, ... being subclasses of 
> > >Property (these classes might have many superclasses)
> > >  - Having a unique slot "hasProperty" with a value being a Class, 
> > >with the allowed class "Property" (thus also allowing Property's 
> > >subclasses)
> > >
> > >  That way, instead of having to define zillions of slots (i.e. at 
> > >least one per new subclass of Property) and writing:
> > >
> > >MyConcept hasContact Contact
> > >MyConcept hasHow How
> > >MyConcept hasWhat What
> > >.... and as many as there are different possible properties
> > >
> > >we could simply write things like:
> > >
> > >MyConcept hasProperty Property  (with multiple cardinality, this 
> > >would cover all the above: no need to predefine all possible cases)
> > >
> > >  and if we need to be more precise (restrict allowed properties):
> > >
> > >MyConcept hasProperty (Class with superclass Contact or 
> How or What)
> > >
> > >  Anyone experienced could tell if my own view is really really 
> > >wrong? Or incompatible with the way description logics and 
> reasonners 
> > >work? I hope this could make our lives easier when we stop playing 
> > >with toy-ontologies and go into the big ones.
> > >
> > >Sebastien.
> > >  
> > >
> > 
> 
> --
> --------------------------------------
> |                                     
> | Dr. Brian Thomas                    
> |                                     
> | Dept of Astronomy                   
> | University of Maryland-College Park
> |
> | Phone: (301) 405-2312               
> | Fax: (301) 314-9067                 
> |                                     
> --------------------------------------
>