- From: Jim Hendler <hendler@cs.umd.edu>
- Date: Tue, 17 Jun 2003 07:53:57 -0400
- To: Alan Rector <rector@cs.man.ac.uk>
- Cc: public-webont-comments@w3.org
At 9:07 AM +0100 6/17/03, Alan Rector wrote: >Jim > >As I said in the informal discussions. I accept the practical >difficulties; this is probably the least bad short term solution. > >I would be very concerned if the postponement were prolonged. We are >unable to migrate key applications from DAML+OIL to OWL without >QCRs. I am also reluctant to encourage my colleagues who want to >start working on Anatomy to use something which is obviously flawed >for their requirements and requires awkward work-arounds. > > >In short, I accept the proposal, reluctantly, but urge the Committee >to make the postponement as brief as possible. The longer the >delay, the greater the pain when the change is made. > >I will read the proposals carefully and comment in due course. > >As for QCRs not having been needed in Protege, I suspect this is due >to a combination of three factors a) It being being less of a >problem in a less expressive language with less inferential power so >that the defects in the work arounds are less apparent b) the use >of alternatives such as PAL constraints which are not available in >OWL; c) just accepting that the only way to do it is to to create >multiple slots to carry the load. We know from experience that this >solution scales badly and is difficult to understand once you add a >classifier. > >(BTW I understand that Holger Knublauch at Stanford's >implementation of an OWL plugin for Protege has made provisions in >the design for extension to QCRs when available.) > >Regards > >Alan Alan- thanks again for raising this issue. I, personally, will encourage people (and invite you as well) to work on the publication of a Note that explains QCRs and how they could be added to OWL once we get the current version out the door. I appreciate your being so understanding of the complexity of the undertaking to develop this recommendation. -Jim H. -- Professor James Hendler hendler@cs.umd.edu Director, Semantic Web and Agent Technologies 301-405-2696 Maryland Information and Network Dynamics Lab. 301-405-6707 (Fax) Univ of Maryland, College Park, MD 20742 *** 240-277-3388 (Cell) http://www.cs.umd.edu/users/hendler *** NOTE CHANGED CELL NUMBER ***
Received on Tuesday, 17 June 2003 07:54:04 UTC