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RE: Cool URIs, the Semantic Web and Everything

From: Hausenblas, Michael <michael.hausenblas@joanneum.at>
Date: Thu, 20 Dec 2007 08:45:54 +0100
Message-ID: <768DACDC356ED04EA1F1130F97D2985201449D3F@RZJC2EX.jr1.local>
To: "Leo Sauermann" <sauermann@dfki.uni-kl.de>
Cc: <semantic-web@w3.org>, "Leo Sauermann" <leo.sauermann@dfki.de>


Thanks for your explanation. I remain not totally convinced :)

So, *if* we agree on what you said, IMHO we should 
reconsider the following paragraph in 'Cool URIs' [1]:

'The solutions described in the following apply to deployment scenarios 
in which the RDF data and the HTML data is served separately, such as a
standalone RDF/XML document
along with an HTML document. The metadata can also be embedded in HTML,
using technologies such as
RDFa [RDFa Primer], microformats and other documents to which the GRDDL
[GRDDL] mechanisms can be applied. 
In those cases the RDF data is extracted from the returned HTML

Still unsure if this is just the tip of the iceberg ...


[1] http://www.w3.org/TR/2007/WD-cooluris-20071217/#solutions

 Michael Hausenblas, MSc.
 Institute of Information Systems & Information Management
 JOANNEUM RESEARCH Forschungsgesellschaft mbH

>-----Original Message-----
>From: Leo Sauermann [mailto:sauermann@dfki.uni-kl.de] 
>Sent: Thursday, December 20, 2007 3:43 AM
>To: Hausenblas, Michael
>Cc: semantic-web@w3.org; Leo Sauermann
>Subject: Re: Cool URIs, the Semantic Web and Everything
>Hi Michael, RDFa people,
>The question is if httpRange-14 [2] is valid in the case of XHTML+RDFa.
>The answer is that httpRange-14 is to distinguish URIs for information 
>resources ("web documents") from real-world objects (the person 
>"Alice"). As such, it is a recommendation on URIs.
>RDFa is an encoding of RDF, and typically an RDFa document has two 
>relations to URIs:
>a) the URI of the RDFa document (=the information resource where I can 
>download the RDFa document)
>b) the URIs used as subjects, predicates, objects inside RDF 
>written inside RDFa documents
>a) is usually a http-200 uri, and a) is an information resource (= a 
>In the rdf statemetns written inside  A, you would use both URIs for 
>real-world objects and information resources.
>example (I don't know  rdfa syntax by heart now, assume this is rdfa):
>document at www.example.com/homepage/aboutAlice
><p rdf:about="http://www.example.com/identifiers/alice#this">
>  rdf:type foaf:Person.
><p rdf:about="http://www.example.com/moreidentifiersusing303/bob">
> rdf:type foaf:Person
>assuming this would be valid RDFa, the URI .../aboutAlice is a 
>http-return-200 informaiton resource
>.../alice#this is a real-world object as it is not a document (as I 
>understand timbl on that)
>...303/bob is not intuitively distinguishable - if you ignore the 
>rdf:type relation you don't know what it is. So for this uri you do a 
>HTTP get and the server would return a 303 redirect as described in 
>"cool uris".
>once oyu did the 303, you knowthat ....303/bob is a real world object.
>so RDFa and 303'/httprange14 are recommendations caring about 
>angles, 303 is only concerned about URIs, RDFa about an RDF 
>serialization. Technically they don't interfere.
>If I would use RDFa much and would like cool uris, I would go for 
>#-uris, they are simple to use and easy to embed in RDFa.
>but as shown above, you can use any URI you want inside rdfa.
>Hausenblas, Michael schrieb:
>> ===
>> Disclaimer: Michael, with his RDFa-Task-Force-member hat off ;)
>> ===
>> As I gathered "Cool URIs for the Semantic Web" is a Working 
>Draft, now.
>> Congrats to Leo and his team, great job! 
>> The following might sound like a naive question - and I might 
>> have missed something :) - but: Is TAG finding httpRange-14 [2] 
>> equally valid in the case of XHTML+RDFa?
>> I've put together some initial thoughts at the ESWiki [3]
>> - any comments welcome!
>> Cheers,
>> 	Michael
>> [1] 
>> [2] http://www.w3.org/2001/tag/issues.html#httpRange-14
>> [3] http://esw.w3.org/topic/RDFa_vs_RDFXML
>> ----------------------------------------------------------
>>  Michael Hausenblas, MSc.
>>  Institute of Information Systems & Information Management
>>  JOANNEUM RESEARCH Forschungsgesellschaft mbH
>>  Steyrergasse 17, A-8010 Graz, AUSTRIA
>>  <office>
>>     phone: +43-316-876-1193 (fax:-1191)   
>>    e-mail: michael.hausenblas@joanneum.at
>>       web: http://www.joanneum.at/iis/ 
>>  <private>
>>    mobile: +43-660-7621761
>>       web: http://www.sw-app.org/ 
>> ----------------------------------------------------------
Received on Thursday, 20 December 2007 07:47:44 UTC

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