- From: Martin Hepp <martin.hepp@ebusiness-unibw.org>
- Date: Thu, 30 Sep 2010 14:49:52 +0200
- To: Kingsley Idehen <kidehen@openlinksw.com>
- Cc: public-lod@w3.org, pedantic-web@googlegroups.com
Hi Kingsley, Thanks - that is what I had assumed. Note, however, the majority of the Web vocabularies use the same URI for the entity name reference and the descriptor reference, see the link provided by Michael Hausenblas: http://code.google.com/p/void-impl/issues/detail?id=45 and in particular the little survey by Richard Cyganiak posted on that page. I personally would argue that in the case of ontologies / vocabularies, the conceptual difference between the entity and the descriptor is a lot less significant than when it comes to data, since an ontology is, by definition, a specification, i.e. a document. So both patterns should work in practice, as long as the URI for the owl:Ontology instance is the same as the URI used in conjunction with rdfs:isDefinedBy. Martin On 30.09.2010, at 12:59, Kingsley Idehen wrote: > On 9/30/10 3:06 AM, Martin Hepp wrote: >> Dear all: >> >> We use rdfs:isDefinedBy in all of our vocabularies (*) for linking >> between the conceptual elements and their specification. >> >> Now, there is a subtle question: >> >> Let's assume we have an ontology with the main URI >> >> http://purl.org/vso/ns >> >> All conceptual elements are defined as hash fragment URIs (URI >> references), e.g. >> >> http://purl.org/vso/ns#Bike >> >> The ontology itself (the instance of owl:Ontology) has the URI >> >> http://purl.org/vso/ns# >> >> <http://purl.org/vso/ns#> a owl:Ontology ; >> owl:imports <http://purl.org/goodrelations/v1> ; >> dc:title "VSO: The Vehicle Sales Ontology for Semantic Web-based >> E-Commerce"@en . >> >> So we have two URIs for the ontology: >> >> 1. http://purl.org/vso/ns# for the ontology as an abstract artefact >> 2. http://purl.org/vso/ns for the syntactical representation of the >> ontology (its serialization) > > Yes, you have two HTTP URIs associated with the Ontology. One is the > "Name" of the Ontology Entity (Thing) and the other is the > "Address" (URL) of the Ontology Descriptor Resource. Thus: > > 1. http://purl.org/vso/ns# -- Entity Name Reference > 2. http://purl.org/vso/ns -- Descriptor Resource Address Reference . > >> >> Shall the rdfs:isDefinedBy statements refer to #1 or #2 ? >> >> #1 >> vso:Vehicle a owl:Class ; >> rdfs:subClassOf gr:ProductOrService ; >> rdfs:label "Vehicle (gr:ProductOrService)"@en ; >> rdfs:isDefinedBy <http://purl.org/vso/ns#> . <=========== >> >> #2 >> vso:Vehicle a owl:Class ; >> rdfs:subClassOf gr:ProductOrService ; >> rdfs:label "Vehicle (gr:ProductOrService)"@en ; >> rdfs:isDefinedBy <http://purl.org/vso/ns> . <=========== >> >> >> I had assumed they shall refer to #1, but that caused some debate >> within our group ;-) > > You refer to Entities (Things) by Name Reference for Linked Data to > work i.e. Names resolve to Descriptor Resources which may be > serialized from Linked Data Server to User Agent using a variety of > data formats such as: HTML+RDFa, RDF/XML, N3/Turtle, N-Triples, TriX > etc.. >> >> Opinions? > > Also cc'd in the pedantic web folks for comments :-) > >> >> Best >> >> Martin >> >> >> > > > -- > > Regards, > > Kingsley Idehen > President& CEO > OpenLink Software > Web: http://www.openlinksw.com > Weblog: http://www.openlinksw.com/blog/~kidehen > Twitter/Identi.ca: kidehen > > > > > >
Received on Thursday, 30 September 2010 12:50:53 UTC