Re: DAML-S expressiveness challenge #1

Tim Finin wrote:
> 
> > From: www-rdf-logic-request@w3.org
> > [mailto:www-rdf-logic-request@w3.org] On Behalf Of Ian Horrocks
> > ...
> > Another possible interpretation is some sort of "role value
> > map", as it is called in description logics. i.e., we may
> > want to say that for all pairs of individuals (x,y) related
> > by some property P (or some chain of properties), the P1
> > property of x and the P2 property of y must have the same
> > individual as their objects. I believe that we can't capture
> > this in DAML+OIL - if we can then we made some mistake
> > somewhere as the language would certainly be undecidable.
> 
> I understood that this was what David needs, or something close to it.

Yes, as I replied earlier, that is what I need.  And I appreciate, of
course, the concern about decideability, with respect to the general way
this has been framed above.

But what about 2 simpler alternatives:

(1) What about if we could say <P1 sameValuesAs P2> - meaning simply
that the set of values of all the instances of property P1 is precisely
the same as the set of values all the instances of property P2 (and
again, there's no assumption that P1 and P2 have the same domain)?  (I'm
asking, not so much how this might be useful, but whether it would be a
reasonable addition to DAML+OIL.)

(2) And if (1) seems reasonable, what about if we could then say <P1
sameValuesWithinNamespaceAs P2> - meaning that the set of values of all
the instances of property P1, for which the domain object is in any
particular namespace N, is precisely the same as the set of values all
the instances of property P2, for which the domain object is in that
same namespace N?  Would something like that be reasonable (because I
can imagine it being very useful)?

- David

> We want to be able to say, for example, that a Process has two
> steps and that the output of step one must be the same individual
> as the input of step two.  If we don't have this in our language then it
> may be very hard to model complex processes which have sub-processes
> that have constraints between them. For that matter, it will be hard to
> model complex things composed of parts which have constraints among
> them.
> 
> Tim

Received on Monday, 9 July 2001 03:45:49 UTC