RE: Short briefing/background doc't regarding RDFa, prefixes and HTML

Michael Steidl, the IPTC MD, has sent me the following summary of 
the key characteristics of QCodes.  I've slightly re-worded it.

1  A QCode is a short format for a URI/IRI which identifies a 
   Semantic Web resource (which we refer to as a Concept).

2  The IPTC design for Concepts and their URI identifiers - 
   Concept IDs - is:

   2.1  Each Concept ID is a member of one and only one Controlled 
        Vocabulary (CV).  A Concept may be included in many CVs, 
        using different Concept IDs.

   2.2  Each CV has a unique URI as its identifier, eg:
        http://cv.iptc.org/newscodes/mediatopic/

   2.3  Each Concept represented by a CV has a code in that CV.  
        Appending this code to the URI of the CV creates the Concept 
        ID URI.

   2.4  If the provider of a CV wants to make the Concepts 
        represented by the CV compatible with the Semantic Web then 
        the URIs must comply with the requirements for Web resource 
        identifiers.

3  The format of a QCode is "the short name of a CV":"the code of 
   the Concept", eg "medtop:01000000".

4  The "short name of a CV", called an "alias", is mapped to the CV 
   URI by a mapping table called a "catalog".  An example of a 
   catalog entry is:
   <scheme alias="medtop" uri="http://cv.iptc.org/newscodes/mediatopic/"
/>

5  A QCode can be resolved to a Concept ID URI by mapping the alias 
   to the CV URI and appending the "the code of the Concept", eg:
   http://cv.iptc.org/newscodes/mediatopic/01000000

6  There is no generic algorithm for splitting a Concept ID URI into 
   a CV URI and a Code.  If such an algorithm is needed, it must be 
   defined by the provider of the CV and it must comply with the 
   design rules above.

Misha


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Received on Friday, 4 February 2011 11:15:31 UTC