Re: On the integration of Topic Maps and RDF

Yes, but "object layer" transformation is a good example that transformation
is possible without information losses
I think that "object layer"  transformation  could be    a first step
for semantic transformation,
because it seems not hard (?)
to extract explicit semantics from  new object-layer RDF graph and put it
into explicit semantic declaration (RDFS, DAML)
and
transform  object-layer RDF graph  into "semantic" RDF file according new
schema definition

Best regards
MSc Andrei S. Lopatenko
Researcher
Vienna University of Technology
Extension Centre
http://derpi.tuwien.ac.at/~andrei/
----- Original Message -----
From: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
To: <andrei@derpi.tuwien.ac.at>
Cc: <lobrst@mitre.org>; <lacher@db.stanford.edu>; <gdm@empolis.co.uk>;
<www-rdf-interest@w3.org>
Sent: Wednesday, August 22, 2001 4:35 PM
Subject: Re: On the integration of Topic Maps and RDF


> Agreed, the information can be regenerated from the transformed RDF.
> However, the regeneration cannot be performed in RDF, as some external
> information is needed, whether in the form of some unspecified rules
> language or in the form of informal side-agreements.
>
> My view is that semantic transformations should not require any of this
> extra information.
>
>
> From: "Andrei S. Lopatenko" <andrei@derpi.tuwien.ac.at>
> Subject: Re: On the integration of Topic Maps and RDF
> Date: Wed, 22 Aug 2001 15:50:32 +0200
>
> > I completely agree that semantic information must not be lost in
> > transformation.
> > But really it was not lost in "object layer" mapping suggested in the
> > article.
> > Semantic information about meaning of RDF resources transformed from XTM
is
> > implicitly declared in RDF  graph of resourses
> > and could be extracted by inference engine. In F-Logic query example
> > semantic of element is extracted in a such way (roleLabel condition).
>
> I would not state that the extra information is implicit in the RDF.  It
> requires extra information, such as inference rules, to be recovered.
>
> > So there are several possible ways to map TM into RDF
> >
> > 1 The one is preserving explicit semantic
> >     XTM ->  RDF Resource graph +  RDF Schema (or DAML+ OIL, OIL)
> > For example, such classes as country, natural-resource should be defined
in
> > the schema
> > And then query should be asked using that new terms
> > ...
> > natural-resource -> pertoleum;
> > ...
> > 2 Another is "object layer"  mapping which just encode XTM graph as a
RDF
> > graph   and semantic is stored implicitly in that graph.
> > The query should contain statements for extracting semantic information
> > such in F-Logic  in the article
> > ...
> > tms:roleLabel->natural-resource;
> > ...
> > or semantic should be provided by inference engine
> >
> > But from the point of view of the article  - to develop query engine
which
> > can also include XTM resources into  RDF
> > both ways are suitable. The difference is only in queries. Information
is
> > not lost.
>
> Not lost to a fully capable reasoner, such as a human.  However, it is
lost
> to an RDF (only)-capable agent.
>
> > Maybe, for other applications it is neccesity to have explicitly
declared
> > semantic, bot not for this?
> >
> > Best regards
> > MSc Andrei S. Lopatenko
> > Researcher
> > Vienna University of Technology
> > Extension Centre
> > http://derpi.tuwien.ac.at/~andrei/
>
> Peter F. Patel-Schneider
> Bell Labs Research
>
>

Received on Wednesday, 22 August 2001 11:16:52 UTC