An observation made during today's discussion is that the multiple modeling levels that we run into when we talk about "quantities" really confuses the discussion. In the Date-Time effort, we have taken the approach of defining separate terms for each of these level, viz: "quantity", "particular quantity", "quantity value", "quantity kind". QUDV apparently makes some of these implicit, for example, a "quantity value" could be understood as an instance of a QUDV "quantity".
I suggested that one way to make progress on this discussion is to review the UoM draft UML model at http://ontolog.cim3.net/cgi-bin/wiki.pl?UoM_Ontology_Standard_UML_Model_Draft and to try to relate each of our concepts to this model. Not that I entirely agree with the UoM model, but it does provide a "neutral" starting point for our discussion, one that does try to call out the different modeling levels.
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Mark H. Linehan
STSM, Model Driven Business Transformation
IBM Research
phone: (914) 784-7002 or IBM tieline 863-7002
internet: [email protected]