- From: Deborah McGuinness <dlm@KSL.Stanford.EDU>
- Date: Sat, 27 Apr 2002 16:37:02 -0700
- To: www-webont-wg@w3.org
Frank van Harmelen wrote: > -------- Original Message -------- > Subject: RE: LANG: compliance levels > Date: Thu, 25 Apr 2002 12:38:05 +0300 > From: "Ziv Hellman" <ziv@unicorn.com> > To: "Frank van Harmelen" <Frank.van.Harmelen@cs.vu.nl>,"Mike Dean" <mdean@daml.org>,"Enrico Motta" <E.Motta@open.ac.uk>,"Ian Horrocks" <horrocks@cs.man.ac.uk>,<herman.ter.horst@philips.com>,"Peter Patel-Schneider" <pfps@research.bell-labs.com>,"Christopher Welty" <welty@us.ibm.com>,"Jim Hendler" <hendler@cs.umd.edu>,"Raphel Volz" <rvo@aifb.uni-karlsruhe.de>,"Deborah McGuinness" <dlm@ksl.stanford.edu> > CC: <www-webont-wg@w3.org> > > Two comments: > > 1) Please provide more detail as to exactly what you intend by stating > 'functionality of properties' > functionality of roles in our proposal is equivalent to stating an at most 1 restriction. (thus the role has either 0 or 1 filler but no more). It also abides by the same side condition as exists in DAML+OIL - ie., it is not allowed to state that a role is simultaneously functional AND transitive. > > 2) As recent email exchanges on the WebOnt forum indicate, the > distinction between primitive and defined classes can be tenuous, at > least with full DAML+OIL expressiveness. Will the same be true of > compliance level 1 of OWL? I guess I need more detail on the tenuous nature of defined/primitive distinction in order to address this question. I think we do not have a choice in daml+oil/owl/fowl but to solve the issue of grouping statements somehow and thus will have a mechanism for grouping an entire term definition together thus solving the problem of potentially having sufficiency conditions for membership in multiple places in a knowledge base. If this problem is solved, do you still have other problems with the primitive/defined class distinction? Deborah > > >-----Original Message----- > >From: Frank van Harmelen [mailto:Frank.van.Harmelen@cs.vu.nl] > >Sent: Monday, 22 April, 2002 18:28 > >To: Mike Dean; Enrico Motta; Ziv Hellman; Ian Horrocks; > >herman.ter.horst@philips.com; Peter Patel-Schneider; > >Christopher Welty; Jim Hendler; Raphel Volz; Deborah McGuinness > >Subject: Re: LANG: compliance levels > > > > > >(Sorry to some of you for resending this, but some people fell > >of the original addresslist of this msg). Please reply to this > >copy to make sure your reply reaches all. > > > >---- > > > >A small group met at KR'02 (ter Horst, Patel-Schneider, > >Horrocks, Welty, McGuinness, van Harmelen), discussing the > >contents of compliance level 1 for OWL. We solicit reactions > >from those volunteered for this task. Please do this by > >immediate response, so that we can report back to the WG next > >Thursday. > > > >We propose to use for level 1 RDF Schema on Steroids, > >(using the terminology from Frank's Thursday 18 April message) > >with additionally: > >- properties can be declared functional > >- datatypes (details depending on resolution by RDF Core). > > > >The main motivation for this choice is aimed at tool developers: > >this level gives tool developers a useful language to aim at > >that is significantly smaller than DAML+OIL, while imposing as > >few restrictions as possible on toolbuilders that want to > >extend beyond this compliance level. Putting in any additional > >features (such as universal local range restrictions) into > >level 1 will make it much harder to go beyond this basic level > >(for example the interaction with existential restrictions). > > > >Written out in full, this amounts to: > > > >RDF Schema stuff > > primitiveclass > > subClassOf > > subpropertyof > > domain > > range > > Property > > named & unnamed Individual > > > >(In)equality > > sameClassAs > > samePropertyAs > > sameIndividualAs > > differentIndividualAs > > > >Property characteristics > > inversOf > > transitive > > symmetric > > > >Plus: functionality of properties (= at most one value for a property) > > (with the usual side condition that this cannot be applied to > > transitive properties, same side condition as in DAML+OIL) > >plus: datatypes (unclear at this moment what this means precisely, > > pending on RDF Core decisions. > > > > > >Frank, > >Deborah. > > ---- > > > > -- Deborah L. McGuinness Knowledge Systems Laboratory Gates Computer Science Building, 2A Room 241 Stanford University, Stanford, CA 94305-9020 email: dlm@ksl.stanford.edu URL: http://ksl.stanford.edu/people/dlm (voice) 650 723 9770 (stanford fax) 650 725 5850 (computer fax) 801 705 0941
Received on Saturday, 27 April 2002 19:37:46 UTC