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Re: Correct Usage of rdfs:idDefinedBy in Vocabulary Specifications with a Hash-based URI Pattern

From: Dan Brickley <danbri@danbri.org>
Date: Wed, 20 Oct 2010 19:30:04 +0200
Message-ID: <AANLkTincoueTUcC=HcJY_3+e3cyD3DdiCw30ka-fsmMx@mail.gmail.com>
To: Martin Hepp <martin.hepp@ebusiness-unibw.org>
Cc: public-lod@w3.org
On Thu, Sep 30, 2010 at 9:06 AM, Martin Hepp
<martin.hepp@ebusiness-unibw.org> 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)
>
> 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#> .  <===========

#1 gets my vote...

(The isDefinedBy property originally had use cases in mind for
situations where the URI of the vocab couldn't be discovered in Webby
fashion through dererencing, eg. uuid: or urn: -based identifiers for
the terms or vocab). As it turned out, the world learned to live with
using http: everywhere, so that particular need faded somewhat :)

Dan

cheers,

Dan

> #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 ;-)
>
> Opinions?
>
> Best
>
> Martin
>
>
>
Received on Wednesday, 20 October 2010 17:30:38 UTC

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