Re: Advancing translational research with the Semantic Web

On May 18, 2007, at 3:40 AM, Phillip Lord wrote:

>
>>>>>> "MK" == Marijke Keet <keet@inf.unibz.it> writes:
>
>   MK> Regarding “reification design patterns” and the reification &
>   MK> OWL (not the thorny logic-based representation of beliefs et
>   MK> al), permit me to mention that support for n-ary relations
>   MK> ---where n may also be >2--- in description logics is already
>   MK> possible with DLR [1] and implemented with reasoner-support in
>   MK> the iCOM tool (the tool may not live up to end-user-level
>   MK> expectations on userfriendliness, but it works) [2].
>
>
> Out of curiosity, can you describe how different or similar this is to
> the result that you can achieve in the N-ary relation design pattern
> for OWL?
>
> Obviously, building things into the DL is nice, but it's not currently
> representable in OWL, so would require tooling support, while the OWL
> N-ary relation pattern doesn't.

I'm afraid I'm unclear how to state the OWL n-ary relation pattern 
(http://www.w3.org/TR/swbp-n-aryRelations) where I really need it. In  
all the examples given, the "lifted"[*] n-ary relation was never  
truly a relation in the first place and always better modeled as a  
class. It's kind of cheating. What if my n-ary relation is transitive  
or if the 3rd argument is a temporal interval over which the relation  
holds?

I think the former is doable with property role chains. Updating the  
n-ary relations note with this - and all the other omitted details,  
such as how to re-represent domain/range, functional properties, n- 
ary relations in restrictions etc - would take a lot of work and  
would make it utterly terrifying to the naive user.

Nevertheless the results are clunky and will need special tool support 
[**] to avoid going insane. In general I am wary of design pattern  
type things - they are usually a sign that the language lacks the  
constructs required to express things unambiguously and concisely. It  
sounds like DLR could provide this, which would be great.

Cheers
Chris

[*] Can someone tell me the correct terminology here? I know there  
are people who hold steadfastly to "reification" insisting it's use  
precedes the RDF usage.

[**] http://composing-the-semantic-web.blogspot.com/ 
2006_07_01_archive.html -- but not much use yet for those of us who  
only use open source tools. Note the use of the R term in the non-RDF  
sense...


> Phil
>
>

Received on Friday, 18 May 2007 17:10:51 UTC