DTV12 — distinguishing business from "internal" concepts

I am concerned that the sheer size of the Date-Time Vocabulary – the number of concepts – may be a barrier to its use. So I propose that we introduce a distinction between concepts that are intended for business use, and concepts that are defined solely to support other concepts. Examples of these “internal” concepts are the various time scales (e.g. weeks scale), concepts that support calendar computations (e.g. months remainder of month value), supporting concepts (e.g. time set, time point sequence), and the Annex D fundamental concepts of sequences, quantities, and mereology. For someone coming new to the Vocabulary, I think the significant number of these internal concepts detracts from goals such as picking the right concept to use for a particular purpose, or understanding the overall design.

Specifically, I propose a new caption called “Intended Use:”, with two possible values “business” and “internal”. By default, concepts would be “business use”, so we need only add this new caption to concepts that we decide are “internal use”. This choice of default fits with the SBVR philosophy that business vocabularies should define business concepts.

When I brought up this idea during last Thursday’s phone call, Donald suggested using Notes. This is certainly possible, but I think there’s value in making this a little more formal. I think tools could use this to simplify things for business users by optionally limiting what is shown to them. Introducing an explicit caption and restricting the possible values used with the caption will work better for that purpose than free-form text in the existing Note caption. The downside of introducing a new caption is an implied need to extend the SBVR XMI format.

This resolution incorporates the resolution for issue 18990 (business users need better guidance for applying DTV concepts). The resolution adopts these measures to address these issues:
1. Adds new convenience concepts with the intent of better supporting "calendar expressions". These convenience concepts build on existing DTV infrastructure.
2. Replaces informative Annex C ("EU-Rent Date-Time Example") with a new version that:
a. Adds a discussion of how to formulate complex calendar expressions, such as "the third Tuesday of each month".
b. Provides a table of DTV concepts recommended for business use.
3. Separates Annex C into a stand-alone document intended to enable business users to apply DTV without referencing the main normative document.
Rather than identifying the intended use of business concepts within the normative text, the new table in Annex C provides a comprehensive list of business-oriented DTV concepts.