- From: Enrico Motta <e.motta@open.ac.uk>
- Date: Sun, 24 Mar 2002 16:41:30 +0000
- To: Frank van Harmelen <Frank.van.Harmelen@cs.vu.nl>, Enrico Motta <e.motta@open.ac.uk>
- Cc: www-webont-wg@w3.org
At 9:41 pm +0100 22/3/02, Frank van Harmelen wrote: > >>2) 'full cardinality' should be in owl-frame > > >I agree it's a judgement call. >You could well be right. well, to quote recent statement from jonathan "_yet_ cardinalities really aren't that hard ... everyone who uses XML Schema deals with cardinalities etc...". Seems strange that such a basic frame construct should not end up in the owl-frame. > > >>3) full set of property specification properties shoud be in >>owl-frame (symmetric, transitive, inverseOf, uniquelyDefining, >>unambigous, etc..) > > >- Again I agree it's a judgement call, and you could be right. >- Notice that "inverseOf" was not in our proposal, > so that's not just a move but also an addition. sorry! I meant a move from daml+oil - i.e, daml+oil property specification elements should be included. >- One inverseOf is added, symmetric comes for free. sure, except that redundancy is a good thing! >- I would be interested what falls under your "etc.." Reflexivity is an obvious one. > > >>4) drop 'primitive class & defined class terminology. I have not >>been able to come up with better alternatives. , so maybe we could >>use a different approach and qualify the attribute specs, rather >>than classes. For instance >> >>PrimitiveClass (male, supers(animal)) >> >> becomes >> >>Class Male (attributeSpec supers(animal)) >> >> >>DefinedClass (Man, supers(Person, Male)) >> >> becomes >> >>Class Man (completelydefiningAttributeSpec supers(Person, Male)) >> >>A possible extension of this approach could be to allow users to >>mix definitional properties with other properties in the same >>definition - i.e., attributeSpec and >>completelydefiningAttributeSpec could also be used in the same >>definition. For instance: >> >>Class Man (completelydefiningAttributeSpec supers(Person, Male), >> (attributeSpec slot (hasAge, range=PositiveInteger))) >> >>The above class spec to be interpreted as stating >> >>Man (x) <-> (Person (x) and Male (x)) >>(Man (x) and hasAge (x, y)) -> PositiveInteger(y) > > >Interesting suggestion. Need to chew on it. OK, while you chew let me emphasise that my suggestion has no semantic implications. It is simply an attempt to allow DL-style specs, without using either the confusing notion of primitive class or daml+oil-style statements, where about a class is defined as the same as a property restriction. Enrico
Received on Sunday, 24 March 2002 11:43:08 UTC