W3C home > Mailing lists > Public > www-rdf-logic@w3.org > August 2001

Metamodeling and Reification

From: Wolfgang Nejdl <nejdl@kbs.uni-hannover.de>
Date: Tue, 21 Aug 2001 00:22:52 +0200
Message-ID: <3B818DBC.19B09FE9@kbs.uni-hannover.de>
To: www-rdf-logic@w3.org
Somehow I did not manage to post this article successfully to rdf-logic
from my Stanford account last week. Maybe it works directly from my
Hannover account ... 
I would love to get feedback from the rdf-logic discussion group.


To: www-rdf-logic@w3.org
cc: Wolfgang Nejdl <nejdl@stanford.edu>,
    "Manfred A. Jeusfeld" <Manfred.Jeusfeld@kub.nl>,
    Martin Wolpers <wolpers@kbs.uni-hannover.de>,
    Hadhami Dhraief <dhraief@kbs.uni-hannover.de>
Reply-To: nejdl@stanford.edu
Subject: Metamodeling and Reification 
Mime-Version: 1.0 (generated by tm-edit 1.5)
Date: Tue, 14 Aug 2001 23:53:17 -0700
From: Wolfgang Nejdl <nejdl@liszt-n.kbs.uni-hannover.de>

As this list has recently discussed several formalizations of
RDF(S)-like languages, as well as the use of RDF(S) as base language
for defining other languages, I am posting a reference to a recent
report (finished one month ago)


which might be useful in this context. In this report we describe the
formalization of an RDF(S) variant called O-Telos-RDF, which provides
enhanced functionalities for meta-modeling and reified statements,
both aspects relevant in using RDF(S) as the base semantic language of
the Web.

The formalization is based very closely on the formalization of the
modeling language O-Telos, which is based on a semantic network model
similar to RDF(S), and which has been used as a (meta) modeling
language in various application areas during the last 10 years. Axioms
and constraints of O-Telos-RDF are clearly defined and contrasted with
both the RDF(S) and the original O-Telos language. This exact
formalization will hopefully contribute to an understanding of both
O-Telos-RDF and (in this context) the current RDF(S) formalization and
its constraints.

Our main goal in describing O-Telos-RDF was to show how expressive a
resource description framework based on simple semantic networks (like
RDF graphs) and a basic formalization of type and subclass relations
can be, therefore exploiting and advancing features already present in
the current RDF(S) formalization, without introducing additional
features not present in the current RDF(S) framework.

Compared with RDF(S), O-Telos-RDF shows its advantages in allowing
easier reification of statements, and in metamodelling applications,
where more than the three abstraction hierarchies provided in RDF(S)
are needed. Furthermore, the class centric approach to property
definition allows the definition of properties with the same name for
different domains, which have different ranges (not possible in

These properties seem to make O-Telos-RDF more similar to DAML+OIL
than RDF(S) is (in the sense that DAML+OIL is more easily/naturally
represented in O-Telos-RDF than in RDF(S)), but our report does not
yet include a comparison of O-Telos-RDF with DAML+OIL concepts.

Further online references:

Short description of O-Telos:
Selected O-Telos-Papers:

Wolfgang Nejdl

Prof. Dr. Wolfgang Nejdl              tel. +49 511 762-19710
Institut für Technische Informatik    fax. +49 511 762-19712
Rechnergestützte Wissensverarbeitung  http://www.kbs.uni-hannover.de/
Educational Technology Lab            http://www.etl.uni-hannover.de/
Learning Lab Lower Saxony             http://www.learninglab.de/
Universität Hannover, Appelstraße 4, 30167 Hannover, Deutschland
Received on Monday, 20 August 2001 18:23:17 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:52:40 GMT