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RE: Qualified Cardinality Restrictions

From: Jeremy Carroll <jjc@hplb.hpl.hp.com>
Date: Mon, 28 Apr 2003 11:40:15 +0200
To: "Ian Horrocks" <horrocks@cs.man.ac.uk>, <www-webont-wg@w3.org>
Message-ID: <BHEGLCKMOHGLGNOKPGHDKEICCBAA.jjc@hpl.hp.com>


I am not sure this proposal is monotonic, maybe I have misunderstood ...

>
> RDF Graphs
> ==========
>
> Again, the obvious solution seems to be to combine some values from
> and cardinality into a single mapping. Simple cardinality constraints
> can then use the same mapping with the qualifying class set to
> owl:Thing, while someValuesFrom can use the minValuesFrom mapping with
> the cardinality set to 1. There are two obvious possibilities for the
> mapping, i.e., attaching the min/max/blank to the valuesFrom property
> name or to the cardinality property name. The first of these seems
> more consistent with the above abstract syntax.
>
> E.g., minVaulesFrom using the valuesFrom property to indicate the "min":
>
> restriction(ID minValuesFrom(required min))   _:x rdf:type
> owl:Restriction .
> _:x rdf:type owl:Class . [opt]
> _:x rdf:type rdfs:Class . [opt]
> _:x owl:onProperty T(ID) .
> _:x owl:minValuesFrom T(required) .
> _:x owl:cardinality "min"^^xsd:nonNegativeInteger .
>
> or using the cardinality property to indicate the "min":
>
> restriction(ID valuesFrom(required min))   _:x rdf:type owl:Restriction .
> _:x rdf:type owl:Class . [opt]
> _:x rdf:type rdfs:Class . [opt]
> _:x owl:onProperty T(ID) .
> _:x owl:valuesFrom T(required) .
> _:x owl:minCardinality "min"^^xsd:nonNegativeInteger .
>
>

If we retain the current RDF graph syntax
_:x rdf:type owl:Restriction .
_:x owl:onProperty T(ID) .
_:x owl:cardinality "min"^^xsd:nonNegativeInteger .

>
> or using the cardinality property to indicate the "min":
>
_:x rdf:type owl:Restriction .
_:x owl:onProperty T(ID) .
_:x owl:minCardinality "min"^^xsd:nonNegativeInteger .


Then I believe that adding the extra triple as suggested is non-mon.


Maybe the proposal is that the current (RDF graph) syntax for cardinality
constraints is dropped and all such restrictions have to be qualified (e.g.
to owl:Thing) - this would be monotonic, but a bit of a drag.

Jeremy
Received on Monday, 28 April 2003 05:40:43 GMT

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