- From: Jim Hendler <hendler@cs.rpi.edu>
- Date: Mon, 17 Dec 2007 07:59:27 -0500
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: schneid@fzi.de, public-owl-dev@w3.org, ian.horrocks@comlab.ox.ac.uk, alanruttenberg@gmail.com
- Message-Id: <6EAA415B-5FF1-42B5-8D08-8C556F3DD8B6@cs.rpi.edu>
I remind you all that the WG reopened the case of QCRs due to Alan Rector's comments. At that point we found no concrete syntaxfor which there was a consensus and we chose to POSTPONE the issue - I don't see that the situation has changed - if the OWL 1.0 WG felt that the DAML solution was appropriate we certainly would have chosen to add it when we reopened the issue. We didn't - and I don't see what has changed -- there's still very few users demanding it, and it still requires creating an arbitrarily ugly and confusing syntax. WHen I thought the OWL 1.1 syntax worked, I was happy with this, but now that it has been exposed to have troubles, I don't see going back to earlier solutions that were already rejected as a way out - seems to me work should go into fixing what is there, and if that is undoable, postpone again. -JH On Dec 17, 2007, at 3:24 AM, Peter F. Patel-Schneider wrote: > The resolution to not include QCRs in OWL had the following rationale > http://lists.w3.org/Archives/Public/www-webont-wg/2002Apr/0264.html > (numbering added): > > The qualified restrictions of DAML+OIL: > 1/ - have added to the difficulty of learning the language > 2/ - have not been used in practice > 3/ - are barely understood by the community > 4/ - potentially add to the difficulty of implementing the language > 5/ - have no compelling use cases > > > Since then there have been multiple calls for the expressive power of > QCRs, including the one by Alan Rector back in 2003, overturning at > least points 2 and 5. The use of QCRs at least partly overturns point > 3. Several implementations of QCRs exist in both UI tools (e.g., > Protege 4) > and reasoners (e.g., Pellet), overturning point 4. > > I think that this is quite a significant change from the situation in > 2002. > > Peter F. Patel-Schneider > Bell Labs Research > > PS: For more information on QCRs in the WebOnt WG, see > http://www.w3.org/2001/sw/WebOnt/webont-issues.html#I3.2-Qualified- > Restrictions > > > > From: Jim Hendler <hendler@cs.rpi.edu> > Subject: Re: [OWLWG-COMMENT] Example why current RDF mapping for > QCRs might hurt OWL-1.1-Full [Re: PROPOSAL to close ISSUE-68] > Date: Sun, 16 Dec 2007 17:18:32 -0500 > >> I have no objection to the solution that was used in OWL 1.0 for >> this. So far, if a feature adds problems to DL, we apparently throw >> it out immediately, but if it causes problems to full, we try to find >> a work around without worrying too much if it cases problems or >> confusion - I just fine this asymmetry to be troubling. So I propose >> we don't include QCRs, since the solution proposed is one that was >> already considered and rejected in OWL 1.0 - what has changed? >> -JH "If we knew what we were doing, it wouldn't be called research, would it?." - Albert Einstein Prof James Hendler http://www.cs.rpi.edu/~hendler Tetherless World Constellation Chair Computer Science Dept Rensselaer Polytechnic Institute, Troy NY 12180
Received on Monday, 17 December 2007 13:00:07 UTC