- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Fri, 28 Dec 2007 14:21:45 +0100
- To: Leo Sauermann <leo.sauermann@dfki.de>
- Cc: "Hausenblas, Michael" <michael.hausenblas@joanneum.at>, Leo Sauermann <sauermann@dfki.uni-kl.de>, semantic-web@w3.org
On 25 Dec 2007, at 21:41, Leo Sauermann wrote: [snip] >>> Q.II: What does http://sw-app.org/mic.xhtml#i identfiy? [snip] >> This is impossible to answer, because the URI's configuration is >> broken. Even the author of the document seems to be confused about >> what he wants the URI to identify. >> >> There is an XHTML representation, and it has a id="i", which >> indicates that the URI identifies an XHTML fragment. >> >> But the XHTML document also encodes an RDF graph using RDFa. In it, >> the author tries to use the same URI to denote a person. He claims >> that a document fragment is a person. That's a nonsensical statement. >> >> Fortunately, this is easy to fix: Remove the id="i" from the >> document, or change it to a different ID, and everything is fine. >> After that fix, the answer would be 1, 2 and 6. >> > I don't know about removing the ID, maybe this would be good. But I > would not make a "must" out of it, why not keep both The application/xhtml+xml MIME type registration says: If there is @id="i" in the XHTML document, then <mic.xhtml#i> designates a part of that document. Thus, web architecture clearly states that <mic.xhtml#i> identifies a document part. Michael's RDFa, however, says that <mic.xhtml#i> denotes a person. That's a contradiction. A person is not a section of a document. Therefore, the @id="i" *MUST* be changed or removed, otherwise we have a URI collision. Richard > > > best > Leo > >> >> >>> >>> >>> >>> Cheers, >>> Michael >>> >>> ---------------------------------------------------------- >>> Michael Hausenblas, MSc. >>> Institute of Information Systems & Information Management >>> JOANNEUM RESEARCH Forschungsgesellschaft mbH >>> Steyrergasse 17, A-8010 Graz, AUSTRIA >>> ---------------------------------------------------------- >>> >>>> -----Original Message----- >>>> From: Richard Cyganiak [mailto:richard@cyganiak.de] >>>> Sent: Friday, December 21, 2007 5:26 PM >>>> To: Hausenblas, Michael >>>> Cc: Leo Sauermann; semantic-web@w3.org; Leo Sauermann >>>> Subject: Re: Cool URIs, the Semantic Web and Everything >>>> >>>> Michael, >>>> >>>> On 21 Dec 2007, at 08:23, Hausenblas, Michael wrote: >>>>> In Cool URIs you are >>>>> referring to a certain >>>>> setup ('deployment scenarios in which the RDF data and the >>>> HTML data >>>>> is served separately'). >>>>> Also the figure right before section 3.1 suggests that there is an >>>>> explicit RDF document and an HTML document, each with a >>>> distinct URL. >>>>> As you know, this is not the case with RDFa. >>>> >>>> Would changing the sentence >>>> >>>> "In those cases [RDFa, microformats and GRDDL] the RDF data >>>> is extracted from the returned HTML document." >>>> >>>> to >>>> >>>> "In those cases, the RDF data is extracted from the HTML >>>> document and no separate RDF document is needed." >>>> >>>> address your complaint? >>>> >>>> The rest of the document's narrative is consistent with use >>>> of RDFa, as far as I can tell. >>>> >>>> Best, >>>> Richard >>>> >>>> >>>>> >>>>> >>>>> So, that is were my confusion stems from. I know that due to time >>>>> constraints you decided that this is the way it is. It >>>> would still be >>>>> nice to learn why the figure right before section 3.1 >>>> (sorry, no label >>>>> available) 'shows the desired relationships between a >>>> resource and its >>>>> describing documents'. >>>>> >>>>> Cheers, >>>>> Michael >>>>> >>>>> [1] >>>> http://lists.w3.org/Archives/Public/semantic-web/2007Dec/0121.html >>>>> >>>>> ---------------------------------------------------------- >>>>> Michael Hausenblas, MSc. >>>>> Institute of Information Systems & Information Management JOANNEUM >>>>> RESEARCH Forschungsgesellschaft mbH >>>>> >>>>> http://www.joanneum.at/iis/ >>>>> ---------------------------------------------------------- >>>>> >>>>> >>>>>> -----Original Message----- >>>>>> From: Leo Sauermann [mailto:sauermann@dfki.uni-kl.de] >>>>>> Sent: Thursday, December 20, 2007 12:36 PM >>>>>> To: Hausenblas, Michael >>>>>> Cc: semantic-web@w3.org; Leo Sauermann >>>>>> Subject: Re: Cool URIs, the Semantic Web and Everything >>>>>> >>>>>> Hausenblas, Michael schrieb: >>>>>> >>>>>> Leo, >>>>>> Thanks for your explanation. I remain not totally >>>>>> convinced :) >>>>>> >>>>>> good, then give a practical example (using concrete RDFa >>>> code) where >>>>>> you think some work needs to be done and provide a >>>> suggestion how to >>>>>> solve it. That you are not convinced may be caused by >>>> various reasons >>>>>> we don't know about, shine light on them. >>>>>> >>>>>> >>>>>> >>>>>> 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 >>>>>> document.' >>>>>> >>>>>> I see no reason for changes until you exactly specify where this >>>>>> paragraph contradicts http-range-14 or other TAG >>>> resolutions or W3C >>>>>> recommendations. >>>>>> >>>>>> the point is that RDF/XML, N3, RDFa and GRDDL are >>>> mimetypes encoding >>>>>> RDF triples while URIs are something used inside these RDF >>>> triples, >>>>>> so at the beginning both are completly different and do not >>>>>> affect >>>>>> each other. >>>>>> >>>>>> "Cool uris" is about URIs and not about RDF serialization. >>>>>> >>>>>> best >>>>>> Leo >>>>>> >>>>>> >>>>>> >>>>>> Still unsure if this is just the tip of the iceberg ... >>>>>> >>>>>> Cheers, >>>>>> Michael >>>>>> [1] http://www.w3.org/TR/2007/WD-cooluris-20071217/#solutions >>>>>> ---------------------------------------------------------- >>>>>> Michael Hausenblas, MSc. >>>>>> Institute of Information Systems & Information Management >>>>>> JOANNEUM RESEARCH Forschungsgesellschaft mbH >>>>>> http://www.joanneum.at/iis/ >>>>>> ---------------------------------------------------------- >>>>>> >>>>>> -----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 >>>>>> statements >>>>>> written inside RDFa documents >>>>>> a) is usually a http-200 uri, and a) is an >>>> information resource (= >>>>>> a >>>>>> document). >>>>>> 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 >>>>>> <html> >>>>>> <p >>>>>> rdf:about="http://www.example.com/identifiers/alice#this" >>>>>> <http://www.example.com/identifiers/alice#this> > >>>>>> rdf:type foaf:Person. >>>>>> </p> >>>>>> <p >>>>>> rdf:about="http://www.example.com/moreidentifiersusing303/bob" >>>>>> <http://www.example.com/moreidentifiersusing303/bob> > >>>>>> rdf:type foaf:Person >>>>>> </p> >>>>>> </html> >>>>>> 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 >>>>>> different >>>>>> 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. >>>>>> best >>>>>> Leo >>>>>> 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] >>>>>> >>>>>> http://lists.w3.org/Archives/Public/public-swd-wg/2007Dec/0103.html >>>>>> >>>>>> [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/ >>>>>> >>>>>> ---------------------------------------------------------- >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>> >>>> >>> >> > > > -- > ____________________________________________________ > DI Leo Sauermann http://www.dfki.de/~sauermann > Deutsches Forschungszentrum fuer Kuenstliche Intelligenz DFKI GmbH > Trippstadter Strasse 122 > P.O. Box 2080 Fon: +49 631 20575-116 > D-67663 Kaiserslautern Fax: +49 631 20575-102 > Germany Mail: leo.sauermann@dfki.de > > Geschaeftsfuehrung: > Prof.Dr.Dr.h.c.mult. Wolfgang Wahlster (Vorsitzender) > Dr. Walter Olthoff > Vorsitzender des Aufsichtsrats: > Prof. Dr. h.c. Hans A. Aukes > Amtsgericht Kaiserslautern, HRB 2313 > ____________________________________________________ > >
Received on Friday, 28 December 2007 13:22:06 UTC