Web Ontology Issue Status

This version:

19 Jul 2002

Previous version:

10 Jul 2002

Editor:

Michael K. Smith (Electronic Data Systems)
michael.smith@eds.com

Copyright © 2002 W3C^® ( MIT, INRIA, Keio), All Rights Reserved. W3C liability, trademark, document use and software licensing rules apply.

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The Date column above is the date of the last change in status.

Abstract

This document enumerates issues before the W3C Web Ontology working group. As such, it is an internal aide to the working group to ensure that all issues are dealt with. It is also intended that the resolution of these questions be recorded here.

Most of these issues are based on discussions concerning the requirements document, Web Ontology Requirements. In general, these issues are proposed requirements or objectives for which the working group has not yet been able to reach consensus, in some cases due to wording problems and in others to conceptual disagreements. The current version is an initial draft based on email from members of the WG, but has not yet been reviewed by the WG as a whole.

Also included are items that have been deemed implicit requirements, as well as features of DAML+OIL that are not mentioned in the requirements document. Most of these need to be explained more fully before discussion of their potential status as a requirement can proceed. Please send any expansions on these to the editor.

Status of this document

This section describes the status of this document at the time of its publication. Other documents may supersede this document.

This document is a working document for the use by W3C Members and other interested parties. It may be updated, replaced or made obsolete by other documents at any time. It is inappropriate to use this document as reference material.

This document has been produced as part of the W3C Semantic Web Activity, following the procedures set out for the W3C Process. The document has been compiled by the Web Ontology Working Group. The goals of the Web Ontology working group are discussed in the Web Ontology Working Group charter.

The working group has not reached consensus on all topics. Those items are documented here.

A list of current W3C Recommendations and other technical documents can be found at http://www.w3.org/TR/.

1. Issues from Requirements Document

1.1 Variables

"Variables: The language should support the use of variables in ontology definitions. Variables allow more complex definitions to be specified, such as the chained properties example above."

Issue raised by Ian Horrocks: wording on variables is too vague.

See proposal to close.

1.2 Definitional Constraints on Conjunctive Types

"Definitional constraints on conjunctive types: The language should support definitions that relate the values of different properties. For example, it should be able to represent the example: style="LateGeorgian" => culture="British" AND date.created="between-1760-and-1811," where style, culture, and dateCreated are all properties"

2 Possible Implicit Requirements

2.1 URI naming of instances

URI naming of instances (ability to refer to instances defined by someone else). This could be merged with "Unambiguous term referencing with URIs", which seems to focus on classes and properties.

See proposal to close.

2.2 Adding Properties to "Someone Else's" Instances

Adding properties to "someone else's" instances.

2.3 Adding Properties to "Someone Else's" Classes

Adding properties to "someone else's" classes (ability to extend a class without subclassing it, ability to split Restrictions across multiple pages/ontologies). This goes with 2, but may conflict with the desire for a greater frame orientation.

See proposal to close.

Our Working group has decided to use RDF/XML as our exchange framework and that the semantics of our documents will be carried by the triple store corresponding to this document (see resolutions of second face to face meeting). The basic RDF model [1] allows documents to refer to and extend the resources defined in other documents.