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Re: Why RDF was a good choice

From: Sam Lerouge <sam.lerouge@rug.ac.be>
Date: Mon, 10 Jun 2002 16:42:35 +0200
Message-ID: <003101c2108d$0fab6880$8853c19d@IVES>
To: <www-mobile@w3.org>

Hello Carl,

The RDF model in itself perhaps does not provide any semantics advantages
compared to XML Schema, as far as I know (I am not an RDF expert). The
advantages come when you start using RDF Schema. Or better, when different
vocabularies are used, that refer to other vocabularies. These
"inter-vocabulary relationships" are not known in XML Schema, I believe. The
previous version of the RDF Schema specification (see
http://www.w3.org/TR/2000/CR-rdf-schema-20000327/) gives some basic hints on
how one could use this.
I think RDF is all about machine-readability, rather than human-readability.
The interesting part of RDF is that a software agent that has a basic
knowledge on some constructs (e.g. the CC/PP model and core vocabulary) can
learn to use other vocabularies when you feed him a new RDF Schema that
refers to the vocabularies he already knows.
One strong point of RDF Schema is the ability to express of relationships
between different vocabularies. I am thinking of a useful application: when
a content provider knows that
a) "requested_file --mime-type--> image/jpeg", and
b) "user_agent --accepts--> [text/html, text/plain, image/jpeg, image/gif]",
then he should be able to deduce the client will be able to process the
data. In order to do so, he must know the relationship between the
"mime-type" property, that belongs to a multimedia metadata vocabulary, and
the "accepts" property, that belongs to some CC/PP vocabulary. Using RDF
Schema (or one of the related technologies, such as DAML+OIL) to express
both vocabularies, and their relationships, would enable the content
provider to learn new vocabularies and their use.

Secondly, when I am thinking about "correct use" (I'd better say "proper
use") of RDF, I am thinking of using RDF Schemas to define vocabularies, and
making use of the rdf:type property in RDF models. I think I wasn't very
clear about that in my previous mail.

Hope this wasn't too much information in one time.

Sam Lerouge
Received on Monday, 10 June 2002 10:42:43 GMT

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