- From: Uli Sattler <sattler@cs.man.ac.uk>
- Date: Thu, 25 Jun 2009 11:00:30 +0100
- To: Bernhard Schandl <bernhard.schandl@univie.ac.at>
- Cc: Owl Dev <public-owl-dev@w3.org>
On 25 Jun 2009, at 10:38, Bernhard Schandl wrote:
> Hi,
>
Hi,
> I have a question regarding OWL DL inference. Given the following
> axiom,
>
> ex:ThingMadeByMan
> a owl:Restriction ;
> owl:onProperty ex:madeBy ;
> owl:allValuesFrom ex:Man ;
> .
so, you say that, if a ThingMadeByMan is madeBy something, then this
something is a Man.
>
>
> and the following assertions,
>
> ex:Bart a ex:Man .
> ex:Something ex:madeby ex:Bart .
now you have a Man, Bart, and Something which is madeBy Bart.
>
>
> is there a way to enfore a reasoner to infer the following?
>
> ex:Something a ex:ThingMadeByMan .
>
yes there is -- but Pellet is right in not inferring this triple from
what you have said above because it doesn't follow from it. What you
want to say is that *if something is madeby a Man (and possibly by
some other things), then this something is a ThingMadeByMan. So there
direction of the implication needs to go the other way round an you
need existential (someValues) restriction... in Manchester Syntax:
Class: ThingMadeByMan
EquivalentTo:
madeBy some Man
This axiom together with your 2 assertions above about Bart and
Something should then imply that Something is ThingMadeByMan
Cheers, Uli
>
> I was not able to produce this triple using the Pellet reasoner, and
> I would be thankful for any hints. Probably I am missing some
> constraints that I should add to the tbox?
>
> Best,
> Bernhard
>
>
>
>
Received on Thursday, 25 June 2009 10:01:27 UTC