- From: Reto Bachmann-Gmür <reto@gmuer.ch>
- Date: Fri, 13 Jul 2007 22:33:10 +0200
- To: Yoshio Fukushige <fukushige.yoshio@jp.panasonic.com>
- Cc: semantic-web@w3.org
Hi Yoshio I think that an ontology can be seen as an information resource an thus have a derefernceable http-uri as its name (some ontolgies have a trailing pound sign, which may indicate that they authors consider an ontology as something more abstract than an information resource). An rdf/xml document is just one representation of an ontology, I would assume a URI ending with .rdf to name such a representation rather than the ontology itself. The ontology can savely have different representations targetted for humans (xhtml, pdf, etc.) or machines (different rdf serialization). If <http://ont.example.org/myOnt/example> is a owl:Class then a webserver would have to return a 303 response since a class is not an information resource. An approach for your single-term ontologies would be: <http://ont.example.org/myOnt/example> rdf:type owl:Ontology. <http://ont.example.org/myOnt/example#> rdf:type owl:Class. It is however a bit unconventional to have a trailing pound-sign at the end of the name of a class, as this usually separates the name of the ontology from the local name of the term. Also this approach doesn't allow graphs using these ontologies to make a very effective use of namespaces when serialized as rdf/xml or n3. If your concern is that one should be able to get a description of a term without having to download a huge ontology I would rather use URIs like http://example.org/myOnt/myClass for an individual class, and configure the webserver to send a 303 pointing to http://example.org/myOnt/myClass-description which dereferences to some rdf containing the description of the class inclusing the triple <http://example.org/myOnt/myClass> rdfs:isDefinedBy <http://example.org/myOnt>. http://example.org/myOnt would dereference to the whole ontology but a typical way to retrieve the definition of a single term wouldn't require to download this huge thing. reto - original message - Subject: Calling the rdf file an ontology? From: Yoshio Fukushige <fukushige.yoshio@jp.panasonic.com> Date: 11/07/2007 10:40 Hi all, I have two questions on what should be called as owl:Ontology. (1) Let's assume we have the following assertion: <http://ont.example.org/myOnt/example> rdf:type owl:Ontology. ...(A) Now if the vocabulary is defined in http://ont.example.org/myOnt/example.rdf, and what is retrieved by GET /myOnt/example HTTP/1.1 Host: ont.example.org Accept: application/rdf+xml is http://ont.example.org/myOnt/example.rdf, then does the following make sense and mean the same thing as (A)? <http://ont.example.org/myOnt/example.rdf> rdf:type owl:Ontology. ...(B) If (A) and (B) mean different things, then which should we use in this situation? Will the decision change if one receives its accompanying html document (example.html) by GET /myOnt/example HTTP/1.1 Host: ont.example.org Accept: text/html or GET /myOnt/example HTTP/1.1 Host: ont.example.org Accept: application/xhtml+xml ? (2) If (A) and (B) above mean different things, does the following make any sense? ----- <rdf:RDF xmlns="http://www.w3.org/2002/07/owl#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"> <Ontology rdf:about="http://ont.example.org/myOnt/example.rdf"/> <Class rdf:about="http://ont.example.org/myOnt/example"/> </rdf:RDF> ----- (this should be in /myOnt/example.rdf ) What I want to do is to put each terms in the vocabulary in mind into separate files defining only that term and name the file after the term name. But I want to remain in DL. That's why I don't write <Ontology rdf:about="http://ont.example.org/myOnt/example"/> in the example above (to separate the Class name from Ontology name). Is that so weird a practice? -- Yoshio Fukushige <fukushige.yoshio@jp.panasonic.com> Network Development Center, Matsushita Electric Industrial Co., Ltd.
Received on Friday, 13 July 2007 20:33:15 UTC