- From: Jeremy Carroll <jjc@hplb.hpl.hp.com>
- Date: Tue, 24 Sep 2002 17:09:01 +0200
- To: "Jeff Heflin" <heflin@cse.lehigh.edu>, "WebOnt" <www-webont-wg@w3.org>
I am amused - RDF, which many perceive as a metadata framework, is not used for carrying the metadata about descriptions of the ontologies used within it. I will abstain if this comes to a vote. (I would even abstain in a straw poll). (This is of course the thin end of the wedge of not using RDF as our syntax). Jeremy > -----Original Message----- > From: www-webont-wg-request@w3.org > [mailto:www-webont-wg-request@w3.org]On Behalf Of Jeff Heflin > Sent: 24 September 2002 16:35 > To: WebOnt > Subject: LANG: Moving issues 5.6 and 5.14 forward > > > > I think an important part of resolving issues 5.6 and 5.14 forward is to > decide whether or not things like (owl:Ontology, owl:imports, > owl:backCompatWith, etc.) should be in the domain of discourse (this is > one of the four major questions from [1]). At last week's telecon and on > this mailing list, I heard a number of people say that they shouldn't > even be in the RDF domain of discourse (which is what I originally > proposed), and I don't recall anyone disagreeing with this position. > Therefore, I am going to make a proposal that treats these features as > "magic syntax" that is outside of both the RDF and OWL domains of > discourse. > > Background: > ------------ > Peter had proposed that imports simply be an attribute on the RDF tag > [2]. > > <rdf:RDF owl:imports="foo:bar"> > ... > </rdf:RDF> > > One problem with this approach is that if there are multiple imports you > have to use space to delimit them. I think this is a bad idea. Not only > is it forcing multiple data values into a single "field" (generally > considered a bad idea in databases), but I think it will make it more > difficult to use standards like XPath and XSLT to point to portions of > and transform OWL documents. > > Mike had proposed putting the imports information outside of the scope > of RDF [3], by doing something like: > > <owl:include import="uri1" /> > > <rdf:rdf ...> > ... > </rdf:rdf> > > In a separate message, he had suggested replacing the rdf:rdf tags with > owl:Ontology tags. > > My proposal was influenced by each of these ideas. > > The Proposal: > --------------- > I propose that imports and versioning information be declared outside of > RDF. In particular I propose the we have an owl:Ontology tag that wraps > all OWL ontologies. The content of this tag is import and versioning > tags followed by the RDF content of the ontology. This has the nice side > effect, that the content of an ontology is finally nested within an > ontology element. > > Here's an example: > > <owl:Ontology xmlns="..."> > <!-- multiple imports are allowed in separate elements --> > <owl:imports resource="..." /> > <owl:imports resource="..." /> > ... > <owl:priorVersion version="..." /> > <owl:backCompatWith version="..." /> > > <rdf:RDF> > <!-- all of are class and property statements go here --> > ... > </rdf:RDF> > </owl:Ontology> > > Thus, RDF parsers can just ignore the surrounding XML content and still > get "partial understanding" of it. OWL parsers can use this extra > information in whatever ways are deemed fit for owl. > > Please let me know what you think of this proposal. If possible, I'd > like to find out how many like it, how many can live with it, and how > many can't live with it. > > If we can get agreement on this, then I think we can start tackling the > issue of how do we define the meaning of imports. > > Jeff > > [1] http://lists.w3.org/Archives/Public/www-webont-wg/2002Sep/0272.html > [2] http://lists.w3.org/Archives/Public/www-webont-wg/2002Sep/0166.html > [3] http://lists.w3.org/Archives/Public/www-webont-wg/2002Sep/0300.html > >
Received on Tuesday, 24 September 2002 11:09:02 UTC