- From: Henry S. Thompson <ht@inf.ed.ac.uk>
- Date: Tue, 26 Apr 2005 16:36:55 +0100
- To: www-tag <www-tag@w3.org>
In trying to come to a clear and concrete statement of my own views on the matter, I've struggled to articulate the space of positions already staked out, as it were. I thought there might be some value in setting out what I've understood to be several of the features which discriminate between different positions. 1) The OFWeb (Old-Fashioned Web) primarily uses http: URIs as a means to an end, namely retrieving encoded character streams with some kind of rendering semantics, the encoding and semantics typically being signalled in the http header. The SemWeb primarily uses http: URIs as an end in themselves, as the constituents of RDF triples i.e. as names for things and relationships between them. Some people believe that at least in the case where http: URIs being used in the SemWeb could be used in the OFWeb, an ambiguity arises. Contrast the use of "http://www.w3.org/" in <rdf:Description rdf:about="http://www.w3.org/TR/webarch/"> <dc:publisher rdf:resource="*http://www.w3.org/*"/> </rdf:Description> and <rdf:Description rdf:about="*http://www.w3.org/*"> <dc:creator> <rdf:Bag> <rdf:li>Ian Jacobs</rdf:li> <rdf:li>Susan Lesch</rdf:li> </rdf:Bag> </dc:creator> </rdf:Description> Feature 1: Ambiguity -- Either it *doesn't exist*, or it exists but *isn't a problem*, or it exists and *is a problem* 2) Stipulate that Ambiguity exists, and that at least it _might_ be a problem, then the question arises as to whether one or more explicit ways/conventions/mechanisms should be adopted to differentiate between the two uses of http: URIs in any particular case. Feature 2: Differentiation -- *Yes* we should make it possible to differentiate, or *no* we shouldn't 3) Stipulate that we should differentate, then the further question arises as to how to do so. I have identified three kinds of signal one could use, there may well be others: Feature 3: Signal -- Either use *far context* (e.g. information in the relevant schema) or *near context* (e.g. the name of the enclosing element or attribute in the XML representation, c.f. Topic Maps resourceRef vs. subjectIndicatorRef) or *internally* (e.g. # convention, tdb: and wpn: proposals) I can characterize my own position as [Ambiguity: is a problem, Differention: yes, Signal: internally] I'll leave argumentation to a subsequent message -- I'd be interested to hear _first_ from others whether this characterisation is accurate and helpful. If not accurate but at least potentially helpful, suggested improvements are of course in order. ht -- Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh Half-time member of W3C Team 2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440 Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk URL: http://www.ltg.ed.ac.uk/~ht/ [mail really from me _always_ has this .sig -- mail without it is forged spam]
Received on Tuesday, 26 April 2005 15:37:02 UTC