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Re: lcsh.info RDFa SKOS and content negotiation - use of RDF-style # IDs in RDFa?

From: Steven Pemberton <steven.pemberton@cwi.nl>
Date: Tue, 30 Sep 2008 13:30:57 +0200
To: "Dan Brickley" <danbri@danbri.org>, RDFa <public-rdf-in-xhtml-tf@w3.org>, "www-tag@w3.org WG" <www-tag@w3.org>
Cc: "Ed Summers" <ehs@pobox.com>
Message-ID: <op.uiakxvi6smjzpq@acer3010.lan>

My preferred practice for naming concepts is to use blank nodes and then  
foaf:primaryTopicOf to ground them:

	<link about="_:StevenPemberton" rel="foaf:primaryTopicOf"  
href="http://www.cwi.nl/~steven/" />
	<link about="_:Amsterdam" rel="foaf:primaryTopicOf"  
href="http://www.amsterdam.nl/" />
	<link about="_:W3C" rel="foaf:primaryTopicOf" href="http://www.w3.org/" />
	<link about="_:TheWasteLand" rel="foaf:primaryTopicOf"  
href="http://en.wikipedia.org/wiki/The_Waste_Land" />
	<link about="_:Love" rel="foaf:primaryTopicOf"  
href="http://en.wikipedia.org/wiki/Love" />

<span about="_:TheWasteLand" property="dc:creator">T.S. Eliot</span>
<a about"_:W3C" rel="foaf:homepage" href="http://www.w3.org/">W3C</a>

I have a nascent proposal to reserve a http scheme to make this easier to  
write:

	<span about="pto:http://en.wikipedia.org/wiki/The_Waste_Land"  
property="dc:creator">T.S. Eliot</span>

but let's not argue about that now.

Best wishes,

Steven

On Tue, 30 Sep 2008 12:50:02 +0200, Dan Brickley <danbri@danbri.org> wrote:

> Looks like http-range-14 still haunts us. I'm looking for some best  
> practice advice for using "#blahblah" URI IDs in RDFa content...
>
> Backstory -
>
> Edd Summers has put up a great site at http://lcsh.info/
>
> It has one page for each concept listed in the Library of Congress  
> Subject Headings, eg. http://lcsh.info/sh85112589 is a URI for a  
> document about the LCSH heading "Religion and the Humanities".
>
> There is RDFa in the HTML page, as well as a complete NTriples zip-file  
> download of the dataset. The RDFa uses a #concept URI to identify the  
> abstract concept that the document is describing with SKOS.
>
> <div class="concept" about="http://lcsh.info/sh85112589#concept"  
> typeof="skos:Concept">
>
> The document also has an RDF/XML representation available by content  
> negotiation. While the triples differ a little (Ed - is this a bug?),  
> they all talk about the SKOS concepts via identifiers that take the main  
> page's URI and append '#concept'.
>
> Is it TAG-acceptable to use a URI in this manner, when  
> http://lcsh.info/sh85112589 is the URI for a document available in RDFa  
> XHTML rather than RDF/XML? What does  
> "http://lcsh.info/sh85112589#concept" name? How do we 'follow our nose'  
> here? Should the media type definition for RDFa allow the assignation of  
> URIs to things other than chunks of markup?
>
> Does anyone have a suggestion for how if at all this should be done  
> differently? My sense is that the HTML spec as-is doesn't license us to  
> assign URIs in this way. And since #foo is to be interpreted w.r.t. to  
> the (set of?) media types we get back as HTTP representations, there  
> seems to be a tension here between using conneg and using rdfa and  
> avoiding having to do http 303 redirects...
>
> cheers,
>
> Dan
>
>
>
> curl -s http://lcsh.info/sh85112589 | rapper -i rdfa - file:
>
> rapper: Parsing file <stdin> with parser rdfa and base URI file:
> rapper: Serializing with serializer ntriples and base URI file:
>
> <file:> <http://www.w3.org/1999/xhtml/vocab#alternate>  
> <http://lcsh.info/sh85112589.rdf> .
> <file:> <http://www.w3.org/1999/xhtml/vocab#alternate>  
> <http://lcsh.info/sh85112589.n3> .
> <file:> <http://www.w3.org/1999/xhtml/vocab#alternate>  
> <http://lcsh.info/sh85112589.json> .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>  
> <http://www.w3.org/2004/02/skos/core#Concept> .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#prefLabel> "Religion and the  
> humanities" .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#altLabel> "Humanities and religion"  
> .
> <http://lcsh.info/sh85112589#concept> <http://purl.org/dc/terms/created>  
> "1986-02-11" .
> <http://lcsh.info/sh85112589#concept>  
> <http://purl.org/dc/terms/modified> "1986-02-11T00:00:00" .
> rapper: Parsing returned 8 triples
>
>
> curl -H "Accept: application/rdf+xml" -s http://lcsh.info/sh85112589 |  
> rapper -i rdfxml - file:
>
> rapper: Parsing file <stdin> with parser rdfxml and base URI file:
> rapper: Serializing with serializer ntriples and base URI file:
>
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#altLabel> "Humanities and  
> religion"@en .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>  
> <http://www.w3.org/2004/02/skos/core#Concept> .
> <http://lcsh.info/sh85112589#concept> <http://purl.org/dc/terms/created>  
> "1986-02-11"^^<http://www.w3.org/2001/XMLSchema#date> .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#prefLabel> "Religion and the  
> humanities"@en .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#broader>  
> <http://lcsh.info/sh85062913#concept> .
> <http://lcsh.info/sh85112589#concept>  
> <http://purl.org/dc/terms/modified>  
> "1986-02-11T00:00:00"^^<http://www.w3.org/2001/XMLSchema#dateTime> .
> <http://lcsh.info/sh85112589#concept>  
> <http://www.w3.org/2004/02/skos/core#inScheme> <http://lcsh.info/> .
> rapper: Parsing returned 7 triples
>
>
>
Received on Tuesday, 30 September 2008 11:32:19 GMT

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