Re: RDF semantics: applications, formalism and education

Graham Klyne wrote:

> I can imagine something like this:
>
> Logic:           DAML+OIL, etc  (Full-strength inference, typing)
> Schema:          RDFS           (Limited inference, typing)
> Abstract syntax: RDF            (Directed labeled graph)
>                   XML Infoset    (Annotated tree)
>                   XML Namespace  <<--------------------- URIs
> Syntax:          XML            ("Pointy brackets")
>                   Characters     (Unicode, UCS, others)
>                   Octets         (Pretty universal now, not always so)
>                   Bits
>
> Different kinds of application can sit on different levels of this
> "Stack".  All computer applications ultimately sit on 'bits', and most sit
> on 'Octets'.  Unicode/UCS is becoming the norm for applications using
> character-coded data (text, XML, and more).  E.g.  it's standard in Java.
>
I think that in order for layers to make sense and complement each other,
the purpose of existence of each layer should be independent.
If the goals intermingle (Lower has  Limited inference and higher has
Full-strength inference), you will restrict higher level functionality with
the lower layer functionality.
It's pretty much the same as someone would try to turn minivan into the
Formula One  -> it's possible, but does it make sense in the mass
production?
If these two layers have the same goals (like inference), they have to be at
the same level of the hierarchy, I mean, that your stack should branch at
XML Infoset layer: one branch is RDF, another one - DAML+OIL.

Mike Smott
mike.smott@crm4j.com

Received on Wednesday, 4 April 2001 11:16:40 UTC