[wg11-owl] Re: Paper: Criticism of the STEP Application Module approach

[Ed Barkmeyer]

David Leal wrote:

> Lothar's paper is very welcome, however it is more than a 'criticism of the
> STEP application module approach'. Lothar's paper shows the problems that
> are caused by the vague definitions of the concepts at the heart of STEP -
> product, product category, product_definition_formation, and product_definition.

I do not know the paper to which David's email refers.
Can someone point me to this paper?

> If we are to do anything with OWL, then we need concepts with precise
> definitions. Lothar lists some concepts/terms that we should be able to
> define, and suggests subclass-superclass relationships between them. What
> about starting by defining these concepts, and creating a useful engineering
> ontology.

I think the idea of creating an engineering ontology is an excellent 
academic research activity, and I might hope that one or two 
universities are already engaged in it.

But as to the SC4 definitions, they are what they are, and the EXPRESS 
models we have reflect the depth of our mutual understanding.  If we 
need to discard most of the existing definitions in order to get the 
EXPRESS models to make any sense, there isn't much value to the STEP 
models, and whether we convert them to "ontologies" is irrelevant to 
their uselessness.

I don't believe that.  My purpose is to get these models turned into 
"ontologies" of the OWL kind, *so that* we can evaluate both the utility 
of the EXPRESS models as an "engineering ontology" and the utility of 
DLs of the OWL kind to engineering applications.

-Ed

P.S. High-level ontological classes, like Product, are deliberately 
large and have very few critical properties.  The question is whether 
the EXPRESS models reflect the critical properties.  And I agree that in 
some cases, they don't!  But the value to SC4 is to identify those 
cases, not to start over.

-- 
Edward J. Barkmeyer                        Email: edbark at nist.gov
National Institute of Standards & Technology
Manufacturing Systems Integration Division
100 Bureau Drive, Stop 8264                Tel: +1 301-975-3528
Gaithersburg, MD 20899-8264                FAX: +1 301-975-4694

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