Re: text descriptions in OWL-S service profiles

Manolis Koubarakis wrote:

> Dear readers,
> I have just noticed that OWL-S v1.1 does *not* give
> a range for property textDescription of class Profile
> while earlier versions (e.g., v1.1Beta) gave 
> **
> as the range.
> Is there a reason for this change?

Yes, the reason is that RDF does not let to have xml:lang attribute on 
typed literals. When we defined the range of textDescription as 
xsd:string then any OWL-S profile that used xml:lang attribute on 
textDescription attribute, e.g. <profile:textDescription 
xml:lang="en">Some description</profile:textDescription>, causes an 
inconsistency. Unfortunately, RDF does not have a URI for plain 
literals. We have the URI rdfs:Literal which is the most general 
datatype, we have the URI for XMLLiterals but there is no URI to 
describe the set of literal values that are not typed, i.e. the ones 
that do not use rdf:datatype attribute. This is considered to be a bug 
in RDF and the OWL-S coalition is going to bring this issue up in SemWeb 
Best Practices working group hoping that at least a temporary solution 
can be found. The solution is just saying that URI rdf:PlainLiteral 
stands for this datatype. But of course the problem is parsers, 
reasoners and RDF processors need to recognize this new datatype URI.

> This change does not seem to be documented in

This was fairly a last minute change and I guess we forgot to add the 
explanation. Thanks for pointing this out.


> Thanks,
> Manolis Koubarakis

Received on Wednesday, 15 December 2004 18:25:33 UTC