- From: Michael Hopwood <michael@editeur.org>
- Date: Mon, 10 Sep 2012 11:31:20 +0100
- To: Cord Wiljes <cwiljes@cit-ec.uni-bielefeld.de>, "public-vocabs@w3.org" <public-vocabs@w3.org>
Cord, This is the URI / URL / URN discussion again. >>> Or in other words: "url" means something rather general: "There is a web document related to the resource that can be retrieved at this url." The opposite, it means something very specific: "this is the Web location of" _____ (where ______ is some network addressable digital file). A URI is just a Web syntax used to identify stuff because the HTTP syntax conveniently allows you a) control over the lookup so you can put some description there (as you said); b) uniqueness also because of a) and the way the HTTP is set up. HTTP URI is paradoxically a very general protocol with very limited application ;) What is lacking is the infrastructure to ensure persistence, quality of lookup and a lot of other things. Most URNs in practical application have those but without the nice HTTP aspect, but in principle they can get it as an added service (e.g. ISBN-A). DOI is an attempt to add all those features together an generalise to the entire Web. Cheers, M -----Original Message----- From: Cord Wiljes [mailto:cwiljes@cit-ec.uni-bielefeld.de] Sent: 10 September 2012 11:17 To: public-vocabs@w3.org Subject: Re: new itemscope or not? The schema.org specification seems to support Jeff's interpretation of the property "url" as "the WWW-address where an electronic copy of the thing that s described can be downloaded". From http://www.schema.org/Thing: Property: url Expected Type: URL Description: URL of the item. Only something that can be downloaded (an information resource) can have a URL. So schema.org's property "url" should only be available for "CreativeWork", not for "Thing" as it is right now. A person for example can't have a url. A person can have a website (which is an information resource) and this website has an url. But then I cannot find any property like "website" or "homepage" for any of schema.org's classes. Combined with the fact that "url" is avalable for class "Thing" (i.e. for everything) I suppose that "url" is in fact used ambiguosly: A book can have a url where you can download the book's text. A person can have a url where you find information about this person. Or in other words: "url" means something rather general: "There is a web document related to the resource that can be retrieved at this url." Essentially its just a "see also" to a document on the web. Cord Am 08.09.2012 04:14, schrieb Young,Jeff (OR): > If I was Godz, I would NOT assume they are the same thing. I would use > schema:url thusly for those decreasingly rare situations where > somebody (especially a remote observer) wants to describe something > that is honest-to-godz located on the Web. For example: > > @prefix observer: <http://example.org/observer/> . > > observer:12345 a <http://purl.org/library/Thesis>; > schema:name "Architectural Styles and the Design of Network-based > Software Architectures"; > schema:author <http://viaf.org/viaf/26681119>; > schema:url > <http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm>. > > As a matter of principle, Roy's (HTML) thesis COULD be upgraded to be > self-describing with some hidden markup (either RDFa 1.1 or Microdata) > and a trivial Apache rewrite (303 redirect) upgrade to www.ics.ici.edu > to replace the observer URI. > > OTOH, if somebody decides that schema:url should be treated the same > as "itemid" (Microdata), "resource" (RDFa Lite 1.1), "rdf:about" > (RDF/XML), etc. then schema:url is a wasted opportunity and we (i.e. > the pedantic observers of reality) would need to find a new vocabulary > term fill this void. > > Jeff > >> -----Original Message----- >> From: Jeni Tennison [mailto:jeni@jenitennison.com] >> Sent: Friday, September 07, 2012 3:15 PM >> To: Ed Summers >> Cc: Dawson, Laura; Thad Guidry; public-vocabs@w3.org >> Subject: Re: new itemscope or not? >> >> >> On 7 Sep 2012, at 20:03, Ed Summers wrote: >>> It would be interesting to know if the HTML spec allowed multiple >>> identifiers, similar to how other HTML attributes work: >> >> "The itemid attribute, if specified, must have a value that is a >> valid URL potentially surrounded by spaces." >> >> http://www.w3.org/TR/microdata/#attr-itemid >> >> So that would be 'no', not according to spec. >> >> I've often wondered whether the schema.org 'url' property is meant to >> be synonymous with itemid. I'm not sure what happens in schema.org >> interpreters when you specify one/other/both/multiple urls... >> >> Jeni >> -- >> Jeni Tennison >> http://www.jenitennison.com >> >> > > -- Cord Wiljes Semantic Computing Group Excellence Cluster - Cognitive Interaction Technology (CITEC) Bielefeld University Phone: +49 521 106 12036 Mail: cwiljes@cit-ec.uni-bielefeld.de WWW: http://www.sc.cit-ec.uni-bielefeld.de/people/wiljes Room H-123 Morgenbreede 39 33615 Bielefeld
Received on Monday, 10 September 2012 10:32:14 UTC