WebOnt Jan 2002 ftf (original) (raw)

W3C * Semantic Web Activity * WebOnt WG * Member Events

Jan 2002 Meeting of the Web Ontology Working Group

Hosted by Lucent Technologies in New Jersey, USA

• Who: participants
• Where: Venue, Hotel Accommodations, etc.
• What:
  • Before: Preparation: Goals, Drafts, history
  • During: Agenda
  • After: Minutes, Actions, and Notes

Dan Connolly, team contact
Jim Hendler, chair
Created Jan 2002 from template
Revision:1.41Revision: 1.41 Revision:1.41 of Date:2002/02/0414:41:52Date: 2002/02/04 14:41:52 Date:2002/02/0414:41:52

Participants

See roll call below.

Also:3 Jan attendee list

Venue: Bell Labs, Murray Hill, New Jersey

Peter F. Patel-Schneider, is the local host; see local info, details

thanks to OpenProjects for #webont and to ILRT for IRC/log facilities.

Preparation: Drafts for Review

Drafts for discussion at this meeting are due 7 Jan 2002.. This allows us to make the best use of our time: folks can come to the meeting prepared, and nobody has reviewed the wrong version, etc.

• The four use case documents:
  1. Use cases on collection management
     (Submitted by Guus Shreiber)
  2. Content Interoperability Use Case final draft
     (Submitted by Leo Obrst)
  3. Stefan Decker's document on web services use cases not available at the time of this writing
  4. General Requirements document
     (Submitted by Jeff Heflin)
• A set of documents relating to how OWL and RDF may be "layered":
  In an email to Webont from Peter Patel-Schneider
  pointers are provided to 4 documents -
  1. RDF Model Theory
     Pat Hayes for the RDF Core WG, 14 December 2001
  2. A Model-Theoretic Semantics for DAML+OIL (March 2001)
     18 December 2001, Frank van Harmelen, Ian Horrocks, Peter F. Patel-Schneider (DAML+OIL Web Ontology Language Submission)
  3. The Web Ontology Language (OWL): RDF Compatible
     4 Jan 2002. Peter F. Patel-Schneider
     • XQuery 1.0 and XPath 2.0 Data Model
       W3C Working Draft 7 June 2001 (latest version)
  4. The Web Ontology Language (OWL'): XML compatible; RDF compatible for base facts
     3 January 2002. Peter F. Patel-Schneider
• Read ahead for DAML+OIL Technical discussion
  (submitted by Ian Horrocks)
• DAML+OIL Issues and Experiences
  by Mike Dean. experiences.n3,v 1.8 2002/01/08 22:17:04 mdean. cf msg of 8Jan

In addition, it is recommended to review the Working Group Charter and the various background references from the working group web page.

Agenda

per 31 Dec msg from the chair. Note the local logistics details, which call for meeting at "Stair 9" entrance at 8:30am.

Monday Jan 14

Tuesday, Jan 15

@@note to self: during charter review, note that the format of publications is part of W3C process. @@also be sure to talk about related groups: TAG, RDF Core, XML Query, ... @@also: introduce the group to Web Architecture: URIs etc.

Minutes

in progress; to follow within 2 weeks of the meeting.

based on IRC log: Mon, 14 Jan, Tue, 15Jan

Welcome - Logistics overview, etc. (14:17Z)

The host welcomed the participants. The 27 participants representing @@ W3C member organizations introduced themselves:

see also:wg membership

1. James Barnette, Defense Information Systems Agency (DISA)
2. Brickley @@
3. Jeremy Carroll, Hewlett Packard Company jjc@hplb.hpl.hp.com, jeremy_carroll@hp.com (intro)
4. Dan Connolly, W3C Team contact connolly@w3.org
5. Jonathan Dale, Fujitsu Limited jdale@fla.fujitsu.com (intro)
6. Jos De Roo, Agfa-Gevaert N. V. jos.deroo.jd@belgium.agfa.com (intro)
7. Mike Dean mdean@bbn.com (invited expert; intro)
8. Stefan Decker, Stanford stefan@db.stanford.edu (intro)
9. Dieter Fensel, Ibrow,dieter@cs.vu.nl (intro)
10. Tim Finin, University of Maryland MIND Laboratory finin@cs.umbc.edu (intro)
11. Nicholas Gibbins, University of Southampton nmg@ecs.soton.ac.uk (intro)
12. Jeff Heflin heflin@cse.lehigh.edu (invited expert; intro)
13. James Hendler, Maryland Information and Network Dynamics Lab at the University of Maryland hendler@cs.umd.edu (chair; intro)
14. Ziv Hellman, <ziv@unicorn.com>,Unicorn Solutions Inc. (intro)
15. Ian Horrocks, Network Inference horrocks@cs.man.ac.uk (intro)
16. Deborah McGuinness, Stanford dlm@ksl.stanford.edu (intro)
17. Libby Miller, University of Bristol libby.miller@bristol.ac.uk (intro)
18. Leo Obrst, MITRE lobrst@mitre.org (intro)
19. Laurent Olivry EDF (Electricite De France) Laurent.Olivry@edf.fr
20. Peter Patel-Schneider, Lucent Technologies pfps@research.bell-labs.com (intro)
21. Marwan Sabbouh, MITRE ms@mitre.org (intro)
22. Guus Schreiber, Ibrow schreiber@swi.psy.uva.nl (intro)
23. Shimizu Noboru, Interoperability Technology Association for Information Processing, Japan (INTAP)
24. Michael Smith, Electronic Data System (EDS) michael.smith@eds.com (intro)
25. Lynn Andrea Stein, lynn.stein@olin.edu (invited expert; intro) (1st day only)
26. Frank van Harmelen, Ibrow Frank.van.Harmelen@cs.vu.nl (intro)
27. Raphael Volz, <volz@fzi.de>,Forschungszentrum Informatik (FZI) (intro)

regrets: Trastour (08 Jan 2002 10:30:41 +0000)

Charter Review (14:25Z)

Hendler reviewed the charter as well as the history of the formation of the group, including the director's decision, and the context: other related groups, etc.

Connolly breifly reviewed W3C process, noting that in the end, it's a tool toward the goal of getting new technologies deployed.

The group confirmed its earlier (3 Jan 2002) decision to name its language OWL. Hendler noted some history of the name, which we agreed to acknowledge.

DAML+OIL Technical Detail (15:38Z)

Ian Horrocks presented DAML+OIL Techinical Detail (cf msg of 14 Jan) @@PDF -- sufficiently accessible? and briefly demonstrated oiled, which does reasoning from DAML+OIL knowledge bases.

@@notes from Frank vH???

Use Case Discussion I (18:02Z)

Hendler suggested that our goal is a W3C working draft with roughly the following outline:

1. compelling use cases (5ish)
2. requirements arising from use cases
3. appendix containing additional use cases not contributing to 2

later it was suggested, and generally agreed, that high-level design goals should be included as well. @@when was that?

Connolly suggested that we use "requirement" in the sense of "if we don't have this, we're not done"; things that we generally agree are desireable but not essential should be called "goals".

Guus Schreiber presented Use cases: collection management.

ACTION Stein: explain "many systems, including frame and oo systems in which metaclasses are used in this way" (18:20Z)

ACTION guus: to provide slides

We took a straw poll around several of the requirements:

POLL: classes as instances of other classes

strong agree

POLL: definitional constraints

mostly unclear; none in favor.

POLL: default knowledge

mostly against, some in favour

POLL: part/whole relations

mostly opposed, few in favour

POLL: property typing

mostly in favour, couple against, few don't care

Leo Obrst presented requirements related to Content Interoperability (18:56Z). We took straw polls around selected requirements:

POLL: inter-ontology references 3.1.1

mostly in favour

POLL: ontology mapping rules, features 3.1.3

jimh rules poll out of charter. see later discussion of why

POLL: ontology composition language 3.1.4

mostly in favour

POLL: inter-ontology sysnonyms/aliases 3.1.8

mostly in favour, no against, few don't care/know

POLL: ontology approximation 3.1.11

mostly against, few don't care, couple in favour

POLL: inter-ontology validation 3.1.12 (annotation/tagging wrt consistency)

most in favour, some disagree, significant number of don't know/care

Stefan Decker presented requirements arising from Web Services use cases (19:26Z).

POLL: language must have a small footprint

mostly against

POLL: language defn is organised in layers

mostly in favour, some against, few neutral

POLL: precisely described semantics

jimh overrules: required by charter

POLL: datatypes in language

mostly in favour

POLL: ability to express relations between types (eg. inequalities on numbers)

jimh postpones

ACTION on Stefan's group to discuss further tomorrow

POLL: ability to give ontologies names and the ability to denote membership of a class in an ontology

mostly in favour, few opposed, few don't know

ACTION pfps: determine status of IP on this issue

Jeff Heflin presented OWL General Requirements. (20:15Z)

ACTION jeffh: to bring implications of this use of subClassOf to attn of RDF Core WG (in context)

POLL: versioning should be requirement for language

mostly in favour, few opposed, few don't care

POLL: subclass/superclass, inverse, equivalence

all in favour

POLL: complex extensions

mostly against, one in favour, few don't know

SWOL Discussion (21:17Z)

Peter Patel-Schneider presented:

• A Proposal for the Web Ontology Language
• Representation and a Proposal for WebOnt

This led to techincal discussion of desirable properties of formal systems etc. No actions/decisions.

Adjourn 'till tuesday...

DAML+OIL Use Review (14:20Z)

Mike Dean presented DAML+OIL Issues and Experiences.

Mention of frame-based system sparked a discussion of user communities. Hendler observed that there are at least two different user communities, and we should be aware of the needs (including documentation, ...) of the various communities.

Hendler clarified our charter w.r.t. rules: it's recognized that rules are needed in the Semantic Web, but ontologies are speparable, and there's more consensus on the technical design at the ontology level

Breakout

A break-out session followed, with groups forming around each of the use-case areas.

Compiling Requirements (18:17Z)

Hendler compiled requirements from the 4 groups.

ACTION JimH: send table of requirements. Done: requirements poll results.

See also:

• Use Cases: Collection management (PDF)
• OWL General Goals and Requirements (ppt)

ACTION Hefflin, Jonathan D., Rafael V.: to draft a requirements document by end of jan.

ACTION danc Ian and mike Dean: will work on a document which evaluates how well daml+oil meets the owl requirements as identified at this f2f meeting

Hot Topics: Decidability, Computability, Efficiency (19:47Z)

@@I think Hendler summarized the discussion, but I don't see it in the logs. Help, Jim?

ACTION ian and frank are delegated the task to come up with the descriptive adj for the reasoner.

Hot Topics: Layering, RDF compatibility (20:19Z)

We reviewed some terms:

Three or four possibilities emerged:

1. a syntactic embedding of owl into rdf:
   OWL : RDF :: RDF : XML
   Syntax: Every OWL document is syntactically an RDF document.
   Semantics: some RDF-entailment conclusions contradict OWL-entailment conclusions. OWL is not sound nor complete w.r.t. RDF(S).
2. owl has syntactic features that go beyond rdf
   OWL : RDF :: FOPL : propositional calculus
   Syntax: some OWL documents aren't RDF documents.
   Semantics: OWL is complete w.r.t. RDF but (of course) not sound.
3. OWL shares syntax and semantics with RDF
   This leads to paradoxes, as noted earlier.

a fourth possibility is peter's owl', in which owl' is a semantic restriction of a syntactic restriction of rdfs

DanC does a staw poll on the three suggestions: which is your favorite? which can you not live with?

1. ~8 prefer; 1 opposed
2. ~2 prefer; ~2 opposed
3. 1 prefer; ~7 opposed

Frank vH observed that perhaps the most significant conclusion to be drawn from these data is that many participants have not arrived at any position on these issues.

ACTION PeterPS, Dieter, Mike Smith: write up layering issues (21:08Z)

14:30 - 15:00 break

Discussion/Planning (21:29Z)

Hendler

Discussion of next steps for group Determination of calendar for next f2fs

(also: next meeting discussion of 14:09Z, 18:15Z)

ACTION JimH: send ftf schedule proposal