RE: A description of the changes necessary to implement named data ranges

Hi!

Looks good to me, and it also looks to me that everything is well for the DL/Full correspondence.

Michael

>-----Original Message-----
>From: public-owl-wg-request@w3.org [mailto:public-owl-wg-request@w3.org]
>On Behalf Of Boris Motik
>Sent: Thursday, March 05, 2009 1:28 PM
>To: 'W3C OWL Working Group'
>Subject: A description of the changes necessary to implement named data
>ranges
>
>Hello,
>
>Here is a description of how the named data range extension would work.
>In
>short, we'd introduce a new type of axioms called DatatypeDefinition.
>These
>would allow you to define a datatype as having some built-in value.
>Then, you
>would be able to write something like this:
>
>(1) Declaration( Datatype( a:myDT ) )
>(2) DatatypeDefinition( a:myDT DatatypeRestriction( xsd:integer ... ) )
>
>Note that (1) is necessary because without it, axiom (2) alone would
>invalidate
>the typing constraints (it would use a URI that is not properly typed).
>These
>axioms would be mapped into RDF into (3) and (4), respectively:
>
>(3) a:myDT rdf:type rdfs:Datatype
>(4) a:myDT a:equivalentClass ...
>
>
>We would call datatypes occurring in such axioms '''defined'''. To
>obtain a
>logic with favorable computational properties, in OWL 2 DL we'd have the
>following conditions:
>
>- If the axiom closure contains a datatype declaration, then the
>datatype MUST
>be in the datatype map or the axiom closure MUST contain a datatype
>definition
>for the datatype.
>
>- A datatype definition axiom MUST NOT define a datatype that is in the
>datatype
>map.
>
>- Datatype definitions MUST be acyclic.
>
>- Datatype restrictions MUST involve only datatypes from the datatype
>map - that
>is, the datatypes defined through datatype definition axioms have no
>facets.
>
>
>
>All these changes would be reflected in the Syntax document. The impact
>to all
>other documents would be quite small:
>
>- Changes to RDF Mapping are minimal and involve mapping the new axiom
>(into RDF
>and back); both changes are minimal.
>
>- Changes to Direct Semantics are minimal and involve defining the
>semantics of
>the new axiom.
>
>- Changes to the XML Syntax are minimal and involve adding a new axiom.
>
>- There are no changes to the RDF-Based Semantics.
>
>Regards,
>
>	Boris
>

--
Dipl.-Inform. Michael Schneider
Research Scientist, Dept. Information Process Engineering (IPE)
Tel  : +49-721-9654-726
Fax  : +49-721-9654-727
Email: michael.schneider@fzi.de
WWW  : http://www.fzi.de/michael.schneider
=======================================================================
FZI Forschungszentrum Informatik an der Universität Karlsruhe
Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe
Tel.: +49-721-9654-0, Fax: +49-721-9654-959
Stiftung des bürgerlichen Rechts, Az 14-0563.1, RP Karlsruhe
Vorstand: Prof. Dr.-Ing. Rüdiger Dillmann, Dipl. Wi.-Ing. Michael Flor,
Prof. Dr. Dr. h.c. Wolffried Stucky, Prof. Dr. Rudi Studer
Vorsitzender des Kuratoriums: Ministerialdirigent Günther Leßnerkraus
=======================================================================