Re: Vocabulary re-use

> Aaron Rubinstein wrote:
[ . . . ]
> > The other part of my question is: does it matter?  Can the Semantic 
> > Web support a plethora of similar but distinct vocabularies as long as 
> > applications are 'smart' enough to interpret the ontology and make 
> > inferences accordingly?

The semantic web has no choice, because there *will* be a plethora of
similar but distinct vocabularies.  As Martin Hepp pointed out, this
will happen because it is easier for the publishers of those
vocabularies, even though it makes more work for the consumers.
Furthermore, different applications have different needs: some will need
finer distinctions than others.  These finer distinctions may be
essential to some applications, but they just add complexity to
applications that don't need them.  This means that, in general,
semantic web developers must learn to deal with ontological mismatches.

> >
> > These questions arise, to a certain extent, out of what seems like a 
> > prevalent practice to convert existing encoding standards from certain 
> > domains that are described using XML Schemas into RDF using RDFS and 
> > OWL, without much awareness of existing ontologies that might suit the 
> > needs of the domain just as well.  In a nutshell, is this OK or is it 
> > bad for the Semantic Web?

If those XML schemas already exist then this sounds like a good first
step to me.  HOWEVER, the initial ontology you get from converting the
XML schema is not likely to be the one you want to use, as it is likely
to reflect too many artifacts of your XML schema.  In my opinion, that
ontology -- which I would call the "native ontology" -- should only be
used to bridge between the XML and the domain ontology that you really
want to use, which should be designed according to the needs of your
domain.  Rules can then transform from the native ontology to the domain
ontology, so that XML instance data can be automatically transformed
into the desired RDF (expressed in the domain ontology).  The benefit of
this approach over using XSLT to transform directly from XML to RDF is
that the transformations can be defined at a more semantic level, so one
is a bit more insulated from the idiosyncrasies of XML.

Incidentally, this is one way that Gloze
http://jena.hpl.hp.com/juc2006/proceedings/battle/paper.pdf 
is used.  Gloze, given an XML Schema, will automatically transform XML
instance data to RDF.  It can also transform from RDF to XML instance
data -- potentially using a *different* XML schema.  Gloze is part of
the jena suite of RDF tools.

On the other hand, if you are already an XSLT wizard anyway, there's
nothing wrong with transforming directly from XML to RDF expressed in
your desired domain model.

> 
-- 
David Booth, Ph.D.
Cleveland Clinic (contractor)

Opinions expressed herein are those of the author and do not necessarily
reflect those of Cleveland Clinic.

Received on Tuesday, 29 September 2009 18:09:18 UTC