[xtm-wg] Conceptual Model - complete version in its current form

[Daniel Rivers-Moore <daniel.rivers-moore@rivcom.com>]

In response to a request for a current version of the complete Conceptual
Model, I attached is a zip file containing the model in its current form.

 <<XTM-ConceptualModel-20010117.zip>> 

This file contains the following items:

- an HTML file comprising a prose Introduction, and a description of the UML
model itself
- a gif file for each diagram in the UML model

When the HTML file is viewed in the browser, the diagrams will appear in the
appropriate places in the text, as all the links are in place (provded the
gif files and the HTML file are in the same folder on the file system).

Notes on Status:

1) The Introduction section is aimed at introducing the underlying concepts
of Topic Maps, and hence at providing a context for the formal model itself
and making it easier to understand. This Introduction was not included in
the Review Specification of 5 December 2000.

2) Apart from the Association Template and Association Prototype sections,
and the renaming of the "Membership" class to "Role" in the Association
diagram, the model has been stable since the Dallas meetings.

3) At the Dallas meetings, there was an Association Template section but no
Association Prototype section. It emerged in discussion that the Association
Template as then described was trying to perform two functions:

a) to define a class of associations that conform to certain constraints
b) to allow an instance association to be derived from another association
and be constrained by the structure of that association.

Based on this realisation, the Association Template construct was clarified,
to show how it combines this double function, and an additional Association
Prototyhe construct was developed, wich performs a related, but distinct
function, namely:

c) to allow an instance association to be derived from another instance
association (its "prototype"), and to specialise or modify it, but with
certain characteristics of the derived association defaulting to those of
the prototype if not explicitly specified in the derived association.

4) Both the Association Template and the Association Prototype constructs
are included in the attached document.

5) To the best of my knowledge, it is the view of the members of the
Conceptual Modelling Subgroup that we need the Association Template
construct in XTM 1.0, but that the Association Prototype construct is best
treated as a first draft of a construct uthat needs more work and is a
candidate for inclusion in later versions of XTM.

Daniel
(chair of the former Conceptual Modelling Subgroup of the XTM Authoring
Group

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XTM-ConceptualModel-20010117.zip