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Re: Another RDDL/RDF proposal

From: Jonathan Borden <jonathan@openhealth.org>
Date: Wed, 13 Nov 2002 08:57:27 -0500
Message-ID: <007501c28b1c$9a489b70$7c674544@ne.mediaone.net>
To: "Dave Beckett" <dave.beckett@bristol.ac.uk>, "Paul Prescod" <paul@prescod.net>, "Brian McBride" <bwm@hplb.hpl.hp.com>
Cc: "Tim Bray" <tbray@textuality.com>, "WWW-Tag" <www-tag@w3.org>

Brian McBride wrote:
>
> o the rdf schema link in the Tim's rddl spec 404'd on me when I tried it
today.

There isn't an rdf schema for this version of RDDL.

>
> o there seems to be some duplication of terms.  What is the difference
> between rddl:nature and rdf:type, which I saw used I think in some of
> Jonathan's examples.  Is rddl:nature a subProperty of rdf:type with a
range
> constraint?  Also there is rddl:description - could you use the dublin
core
> property for that?  Similarly rddl:title.

The relationship between rddl:nature and rdf:type is a good question. My
preference in http://www.rddl.org/RDDL2 is to use rddl:nature as an
rdfs:subPropertyOf rdl:type but doing so may complicate the resultant
syntax.

Perhaps it is not nessary that rddl:nature be the rdf:type of the referenced
resource. I chose that option because that is how Ron Daniel mapped XLink to
RDF in his W3C Note, and in the XLink version of RDDL, I wrote an XSLT
transform that extracted RDF in that way. http://www.rddl.org/RDDL2 uses
that model. We don't have to use that model if people prefer another -- I
picked it in the spirit of reusing Ron's work.

There may be duplication of terms, e.g. rddl:description vs. dc:description
but I don't see a real benefit to reusing the dublic core concept of
"description" or "title". We aren't talking about the title of the document,
rather the title of a rddl:resource. Wouldn't that be overloading terms?

In any case we can always decide to rdfs:subClassOf and rdfs:subPropertyOf
such terms, and write an RDFS that says so. That would both provide a good
syntax for RDDL and allow reasoners to do proper inferences/searches etc.

In any case I am hoping that we can come up with a reasonable syntax*** for
RDDL2 and as long as we can "fix up" the semantics using RDFS/OWL then I'm
happy to compromise on which names we give to things.

Jonathan
*** I am really hoping that if we can come up with a good compromise on
integrating XHTML+RDF then RDDL can provide a guide to using RDF in RDDL and
provide a hopefully useful language with a predefined set of terms but
people would be free to describe their namespaces using their own terms if
so desired. This is the current spirit of http://www.rddl.org/natures and
http://www.rddl.org/properties
Received on Wednesday, 13 November 2002 09:18:35 GMT

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