- From: Ian Horrocks <horrocks@cs.man.ac.uk>
- Date: Tue, 10 Jul 2001 20:12:48 +0100 (BST)
- To: tim finin <finin@cs.umbc.edu>
- Cc: www-rdf-logic@w3.org
On July 10, tim finin writes:
> I'm not exactly sure what David Martin needs to model
> in his work with DAML-S, but here's a simple example
> that I think brings out the problem or at least a related
> one. I'm basing this on an old example from KL-ONE days:
>
> a person is a thing with
> one home address of type address
> a worker is a person with
> one office address of type address
> a homeworker is defined as a worker
> who's home address and office address are the same.
>
> in logic we would (partially) model this as
>
> homeworker(X) <-> person(X), homeaddr(X,A), officeaddr(X,A)
>
> What's missing in DAML+OIL (as far as I understand) is the ability
> to express the equality constraint between the values of the two
> properties which is no nicely done with variables and unification
> in many languages.
Actually, this is a nice example of a case that you CAN capture using
the super-role trick I mentioned earlier in this thread. All you need
to do is add the property "address" and state that both officeaddr
and homeaddr are subPropertyOf address. You can then state that a
person is a homeworker iff they have an officeaddr and at most one
address. I.e.:
officeaddr subPropertyOf address
homeaddr subPropertyOf address
homeworker
sameClassAs
intersectionOf
restriction
onProperty officeaddr
minCardinality 1
restriction
onProperty address
maxCardinality 1
Regards, Ian
>
> --
> Tim Finin, Prof Computer Science & Electrical Eng, Director Inst. for Global
> Electronic Commerce, U Maryland Baltimore County, 1000 Hilltop, Baltimore MD
> 21250. mailto:finin@umbc.edu 410-455-3522 fax:-3969 http://umbc.edu/~finin/
>
Received on Tuesday, 10 July 2001 15:18:49 UTC