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Re: Defining a property to have an EMPTY range?

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Thu, 15 May 2003 10:54:12 +0100
Message-Id: <5.1.0.14.0.20030515104756.04d41e80@localhost>
To: "Roger L. Costello" <costello@mitre.org>, www-rdf-interest@w3.org
Cc: "Costello,Roger L." <costello@mitre.org>

RDFCore had a similar issue

   http://www.w3.org/2000/03/rdf-tracking/#rdfms-boolean-valued-properties

which it resolved suggesting the approach using rdf:type.

As suggested before you can think of secret as a class of documents.  Maybe 
one way to think of it, is that class roger:Secret is the class of 
documents that can be read by people with security clearance 
roger:ClearanceToSecret.  Then one could consider using the class hierarchy 
so that roger:NotQuiteSecret is a superclass of roger:Secret.

But security tends to be an area for specialists, so this could be a really 
bad idea.

Brian

At 08:31 14/05/2003 -0400, Roger L. Costello wrote:

>Hi Folks,
>
>It dawned on me today that there are times when it may be useful to
>state in an RDF Schema document (or an OWL document) that
>
>    "the range of this property is EMPTY"
>
>Example: I would like to be able to "tag" a Document with a security
>classification, e.g.,
>
>    <Document>
>        <secret/>
>        <content>
>            ...
>        </content>
>    </Document>
>
>Note the <secret/> property.  Its purpose it simply to "tag" this
>Document as having a secret classification.
>
>Thus, in an RDF Schema (or OWL document) I would like to state:
>
>     <rdf:Property rdf:ID="secret">
>         <rdfs:domain rdf:resource="#Document"/>
>         <rdfs:range rdf:resource="EMPTY"/>
>     </rdf:Property>
>
>Obviously, this is not correct, as there is no EMPTY in RDF (or OWL).
>
>Am I looking at this incorrectly?  How would you do this?  What are your
>thoughts?  /Roger
Received on Thursday, 15 May 2003 06:32:58 GMT

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