[topicmaps-comment] occurences and modeling resources

[Howard Goldberg <HGoldberg@cstlink.com>]

I have been experimenting with Kal Ahmed's TMTab, and have some questions
about occurences and their reification.

1.  In the conceptual model, an occurence is uniquely identified by an
instanceOf, a scope, and a resourceRef.  Therefore,  it appears that any
occurrence that shares the same tuple should have the same occurence
identifier.  For example, if I have multiple topics that each appear in the
english version of my home page, each occurence in every topic shares the
same identifier, and are reified by one topic whose subjectIndicatorRef is
that single occurence identifier.

2.  If my home page appears in several languages, the reification of my home
page as a resource must be a tree.  The reification of each language version
of my home page becomes a single topic whose subjectIndicatorRef identifies
the occurrence. However, each of these language-specific occurrences is an
instance of a topic reifying my home page,  the subjectIndicatorRef of which
could be some unique URI.  Then, this root node is an instance of a home
page, etc.

Is this correct?  Intuitively, I'd like to model a resource and its multiple
scopes as a single topic, but that's not what the conceptual model
indicates.  This seems to put the burden on the topic map processor, in
order to support interesting queries about resources, and the tool writer,
to hide this complexity from users who want to create resources on which to
map occurrences of other topics.

Regards,
Howard 

Howard S. Goldberg, MD
Director, Clinical Research & Development
Clinician Support Technology
3 Speen Street, Suite 340
Framingham, MA 01701
www.cstlink.com