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RE: Transport XML meta data as well as RDF?

From: Smith, Kevin, \(R&D\) VF-Group <Kevin.Smith@vodafone.com>
Date: Wed, 18 Jun 2008 15:48:01 +0200
Message-ID: <37AC1116121D3F43B9A67CB16E2E79FF4B837F@VF-MBX11.internal.vodafone.com>
To: "Phil Archer" <parcher@icra.org>, "Public POWDER" <public-powderwg@w3.org>

Hmmm...so does that mean that any descriptors more complex than a
triple(s) are treated as 'xmldata'?

E.g. 
<descriptorset>
   <ex:palette type="1">
	<ex:colour>red</ex:colour>	
	<ex:luminance>50</ex:luminance>	
   </ex:palette>
</descriptorset> 

? If so, can we simply say that where the descriptor contains a triple
such as <> ex:color red, then map this to 

       <owl:onProperty rdf:resource="http://example.org/vocab#colour" />
       <owl:hasValue>red</owl:hasValue>

but, if the descriptor is more complex, then map this to 

       <owl:onProperty
rdf:resource="http://www.w3.org/2007/05/powder-s#xmldata" />
       <owl:hasValue>
	  <!-- add XML verbatim-->
	 </owl:hasValue>

The complex descriptors can be easily spotted with the following XPATH:

count(descendant::*) >1 

Just a bit wary of having a wrapper element called <xmldata> if we can
determine that implicitly.

Cheers
Kevin



-----Original Message-----
From: public-powderwg-request@w3.org
[mailto:public-powderwg-request@w3.org] On Behalf Of Phil Archer
Sent: 18 June 2008 14:13
To: Public POWDER
Subject: Re: Transport XML meta data as well as RDF?


Yes, that's fine for POWDER and in terms of the XML schema but what will
the transform make of it? This...

<descriptorset>
   <ex:colour>red</ex:colour>
</descriptorset>

ends up as

<owl:Class rdf:nodeID="descriptorset_1">
   <owl:intersectionOf rdf:parseType="Collection">
     <owl:Restriction>
       <owl:onProperty rdf:resource="http://example.org/vocab#colour" />
       <owl:hasValue>red</owl:hasValue>
     </owl:Restriction>
   </owl:intersectionOf>
</owl:Class>

and there are rules for things like rdf:resource and all that so I think
we'd need an explicit element type so that the GRDDL can turn your
POWDER example into

<owl:Class rdf:nodeID="descriptorset_1">
   <owl:intersectionOf rdf:parseType="Collection">
     <owl:Restriction>
       <owl:onProperty
rdf:resource="http://www.w3.org/2007/05/powder-s#xmldata" />
       <owl:hasValue>
<!--
UKOLN xml quoted here verbaitm
-->

</owl:hasValue>
     </owl:Restriction>
   </owl:intersectionOf>
</owl:Class>

(we'd need to create that 'xmldata' element in POWDER and its term in 
POWDER-S).

Phil.

Smith, Kevin, (R&D) VF-Group wrote:
> HI Phil,
> 
> You can already include that metadata block in a DescriptorSet as
> regards the XML schema, so would that suffice?
> 
> Cheers
> Kev
> 
> E.g.:
> 
> <?xml version="1.0" encoding="UTF-8"?>
> <powder xmlns="http://www.w3.org/2007/05/powder"
> xmlns:dc="http://dublincore.org/schemas/xmls/qdc/dc.xsd"
> xmlns:dcterms="http://dublincore.org/schemas/xmls/qdc/dcterms.xsd"
> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
> xsi:schemaLocation="http://www.w3.org/2007/05/powder wdr.xsd">
> 	<attribution>
> 	
>
<maker><dc:creator>http://people.example.com/kevin</dc:creator></maker>
> 	</attribution>
> 	<dr>
> 		<iriset>
> 	
> <includeregex>http://ukoln.ac.uk/*</includeregex>
> 		</iriset>
> 		<descriptorset>
> 			<metadata xmlns="http://example.org/myapp/">
> 			   <dc:title>UKOLN</dc:title>
> 			   <dc:description>
> 				 UKOLN is a national focus of expertise
> in digital information
> 				 management. It provides policy,
> research and awareness services
> 				 to the UK library, information and
> cultural heritage communities.
> 				 UKOLN is based at the University of
> Bath.
> 			   </dc:description>
> 			   <dc:publisher>UKOLN, University of
> Bath</dc:publisher>
> 	
> <dc:identifier>http://www.ukoln.ac.uk/</dc:identifier>
> 		</metadata>
> 		</descriptorset>
> 	</dr>
> </powder>
> 
> -----Original Message-----
> From: public-powderwg-request@w3.org
> [mailto:public-powderwg-request@w3.org] On Behalf Of Phil Archer
> Sent: 18 June 2008 12:14
> To: Public POWDER
> Subject: Transport XML meta data as well as RDF?
> 
> 
> I've just had an interesting conversation with Karen Van Godtsenhoven
> and Patrick Hochstenbach at the University of Gent who are running a
> project called DRIVER [1] - which is concerned with Open Access
> scientific publications. One question raised was whether POWDER could
> transport XML meta elements as well as RDF. Er... well, it's designed
to
> transport RDF but I wonder how difficult it would be to add support
for
> transporting XML that doesn't get treated as RDF? (there are some very
> well established XML-based metadata systems).
> 
> To try and work through an example I looked at the Dublin Core XML
> implementation guide [2], example 4.3 of which is
> 
> <metadata
>    xmlns="http://example.org/myapp/"
>    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>    xsi:schemaLocation="http://example.org/myapp/
> http://example.org/myapp/schema.xsd"
>    xmlns:dc="http://purl.org/dc/elements/1.1/">
> 
>    <dc:title>UKOLN</dc:title>
>    <dc:description>
>      UKOLN is a national focus of expertise in digital information
>      management. It provides policy, research and awareness services
>      to the UK library, information and cultural heritage communities.
>      UKOLN is based at the University of Bath.
>    </dc:description>
>    <dc:publisher>UKOLN, University of Bath</dc:publisher>
>    <dc:identifier>http://www.ukoln.ac.uk/</dc:identifier>
> </metadata>
> 
> Hmmm... so we have an arbitrary bit of XML that provides data about,
in
> this case, UKOLN. POWDER could be useful in associating this data with
> "everything on ukoln.ac.uk" ?
> 
> I think all we'd need to do would be to define a new element for our
DRs
> of, say, xmldata, and treat it more or less the same as we do tagset
and
> descriptorset in that you can have multiple instances of them but you
> must have at least one of tagset, descriptorset or xmldata for the DR
to
> be valid. In POWDER-S there would be a class with a property that had
> the XML chunk as its value (RDF has specific support for transporting
> XML as the value of a property).
> 
> Something to talk about on our next telecon?
> 
> Phil.
> 
> 
> [1] http://www.driver-repository.be/
> [2] http://dublincore.org/documents/dc-xml-guidelines/
> 
> 
Received on Wednesday, 18 June 2008 13:49:16 GMT

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