Re: SKOS and FOAF

Many thanks for this follow-up, Dan.

Sorry for the confusion in my previous email - we were not using  
"http://xmlns.com/foaf/0.1/20050603.rdf" at all in the past.  I was  
just using it to see whether I could directly open SOME FOAF  
ontology.  We'd been using "http://xmlns.com/foaf/0.1/" which  
previously worked just fine.

As you say - there doesn't appear to be any issue with FOAF per se.   
I can certainly use http://xmlns.com/foaf/0.1/index.rdf as a URI to  
open it directly in SWOOP.  Protege will only directly open Protege  
project files or OWL files, but I assume namespace specs referencing  
this URL inside other OWL file SHOULD be OK.

It now appears the problem must be with some change that has taken  
place with SKOS access.  We were previously using the URL:
	http://www.w3.org/2004/02/skos/core#

However, due to other issues we'd been having with URL-based access,  
we'd all downloaded the other OWL & RDF files we were using via  
owl:import so as to have local fall back files to access.  It appears  
we were accessing the local SKOS file more than we'd known.  What's  
been  happening is we are re-arranging our URL referencing so as to  
regularize it across all our files for an upcoming release.  In so  
doing, we are eliminating any of these local dependencies, so that  
others will not be forced to locally download any additional files in  
order to use our OWL ontologies.

So - for some reason - we don't appear to be able to access the SKOS  
"vocabulary" files we are importing - and THIS also somehow is  
leading to our getting this FOAF error in Protege.

I'll try to work on this some more this evening.

Thanks again for the assistance, Dan.

Cheers,
Bill



On Feb 26, 2007, at 11:13 PM, Daniel Rubin wrote:

> Dan,
> Thanks for the follow up. I'm copying Bill Bug, who is the person  
> who reported the SKOS/FOAF problem, so he can reply to your  
> questions below.
> The tool being used is Protege.
> Thanks
> Daniel
>
> At 10:46 AM 2/26/2007, Dan Brickley wrote:
>> Thanks. It certainly ought to be the case that FOAF and SKOS work  
>> well together. If someone is having trouble, I would like to find  
>> out why.
>>
>> That said, I am having trouble understanding the detail of the  
>> message.
>>
>> http://xmlns.com/foaf/0.1/20050603.rdf is an archive-only snapshot  
>> of FOAF's RDF description, never intended for use as a namespace.  
>> Well, people are free to do so, but it would be excessively  
>> cautious usage, I think.
>>
>> It soulds like they are using some particular toolset. Do you have  
>> any more details?
>>
>> For example, http://www.dasbistro.com/~sam/raptor.lisp seems to be  
>> fixing on that specific URI.
>>
>> http://comments.gmane.org/gmane.comp.misc.ontology.protege.owl/ 
>> 19596 suggests that URI is being used in Protege circles.
>>
>> Could you ask if http://xmlns.com/foaf/0.1/index.rdf works OK for  
>> them?
>>
>> Perhaps the problem is with our content negotiation setup. That  
>> could well be the case. If you can find out what tool is being  
>> used, I could run some tests...
>
>

Bill Bug
Senior Research Analyst/Ontological Engineer

Laboratory for Bioimaging  & Anatomical Informatics
www.neuroterrain.org
Department of Neurobiology & Anatomy
Drexel University College of Medicine
2900 Queen Lane
Philadelphia, PA    19129
215 991 8430 (ph)
610 457 0443 (mobile)
215 843 9367 (fax)


Please Note: I now have a new email - William.Bug@DrexelMed.edu