Re: Picking the Tools

[Jonathan Borden <jborden@mediaone.net>]

Bullard, Claude L (Len) wrote:


> How are these to be combined?
>
> Does it come down to choose a tool and stick with it
> for the duration of a project?

fair enough question.

my apologies if I assumed the previous question was meant in a sarcastic
fashion -- the thought of using UML to model RDF _was_ genuinely humerous to
me, but that's because of a particularly lengthy and arcane thread going on
in the rdf-logic list. there is a group interested in using RDF to represent
predicate calculus/first order logic and the argument is whether RDF as it
currently stands is up to the task. the idea of using UML to model predicate
calculus was more than i could fathom on a monday morning...

on one level people seem to use UML tools to draw pretty diagrams using
rectangles and arrows (formally a directed labelled graph), at the same
level RDF is designed to represent directed labelled graphs and tools exist
to "draw" RDF as diagrams (though with ellipses and arrows instead of
rectangles :-)) RDF is really pretty good at being able to do this sort of
thing, and one could easily imaging an RDF encoding of UML.

RDF draws such directed labelled graphs assuming the nodes in the graph are
named using URIs. It has been suggested that one can use URIs to name
anything, e.g. from RFC 2396 "A resource can be anything that has
identity"...

Well, since a resource can be _anything_ that has an identity, its pretty
hard to get more abstract than _that_. This definition of a resource is
basically as abstract as it gets, indeed the problem may be that its _too_
abstract to be practically useful. The thought of creating something _more_
abstract than a resource...

Topic maps also get pretty abstract, you have topics which can be anything
and subjects which also can be anything (this is a gross oversimplification
but if you want to hear the longer version ...) and it gets pretty hard for
me to understand what the relationship between a URI, resource, topic and
subject really is... so we have lots of people declaring their interest in
somehow combining TM + RDF yet no one has been able to write down a coherent
and definitive explanation of how these _terms_ related to eachother so that
whole area is totally confusing...

And then we have XML Schema and its relationship to both RDF and TM and its
been a fairly long day so don't even get me started...

What was the question again? Oh yeah: how do we pick a tool and stick with
it for the duration of the project... since none of these things really work
together at all in their current state, you just pick the tool you like ...
if you don't want to think you can simply use "Biztalk" and not worry about
any of the three because they are going to do it their own way "microsoft
schema language" in any case.

Ok but suppose you want to do a little thinking on your own, what we need to
do is to sit down and write down these terms and relate them in a logical
fashion. that's why I started to write the "schema algebra" thingie, so that
I could try to make logical sense of all this stuff... if we can at least
agree amongst ourselves what all these terms mean, then we can start
thinking about tools that might interoperate.

-Jonathan

>
> Len
> http://www.mp3.com/LenBullard
>
> Ekam sat.h, Vipraah bahudhaa vadanti.
> Daamyata. Datta. Dayadhvam.h
>
>
> -----Original Message-----
> From: Jonathan Borden [mailto:jborden@mediaone.net]
>
> Uche,
>
> I suspect that you have successfully be flame baited! The suggestion that
> something could actually be _more_ abstract than the combination of RDF,
TM
> and XML Schema ... :-))