On Jun 1, 2011, at 11:00 AM, Rey Segundo Guerrero-Proenza wrote:
> Hi all:
> I need to express Property chains as a disjoint expression:
> r1 o r2 o r3 --> r
> r3 o r4 --> r
I think that the way you would get disjunction is to have two separate
subproperty relations. Each subproperty axiom would be separate and
would not form a conjunction.
It certainly works that way for non-chained properties. If you have
p subpropertyOf r
q subpropertyOf r
then you if either p or q is true, r holds.
> How do you express that in Protègè 4.1? I supposed to use two separate
> expressions was equivalent to conjunction.
That only applies to things like domain and range restrictions, where
each restriction has to be separately satisfied. Subclass and
subproperty axioms are treated as disjuncts. In fact, you can't have
a conjunctive subproperty restriction because OWL doesn't support
property intersection, only class intersection.