DTV_ — Adopt ‘occurrence’ and ‘what-happens state of affairs’ from SBVR

In support of the addition of a very generic concept for all kinds of occurrences to SBVR at the DTV RTF’s request, so that all specifications that define a particular kind of occurrence based on this generic SBVR concept, the Date-Time Vocabulary needs entries to do this.
Resolution:
1. Adopt ‘occurrence‘ from SBVR as specialize it as ‘temporal occurrence’.
2. Adopt ‘what-happens state of affairs has occurrence’ from SBVR as specialize it as ‘what-happens state of affairs has temporal occurrence’.

Revised Text:
In clause 16 immediately before the entry for ‘situation model', INSERT two new entries:
temporal occurrence
Definition: occurrence that occurs for a given time interval

… add whatever contraints are required by DTV on ‘temporal occurrence’, which is adopted from SBVR …

Necessity: A state of affairs will have occurred for a time interval if and only if the state of affairs has an occurrence and the occurrence interval of the occurrence is the time interval.

Necessity: A state of affairs has been actual if and only if an occurrence of the state of affairs is in the past.
Necessity: A state of affairs is actual if and only if an occurrence of the state of affairs is current.
Necessity: A state of affairs will be actual if and only if an occurrence of the state of affairs is in the future.

Necessity: An occurrence has been actual if and only if the occurrence is in the past.
Necessity: An occurrence is actual if and only if the occurrence is current.
Necessity: An occurrence will be actual if and only if the occurrence is in the future.
what-happens state of affairs

… add whatever contraints are required by DTV on ‘what-happens state of affairs’, which is adopted from SBVR …

what-happens state of affairs has temporal occurrence
Definition: ’ what-happens state of affairs has occurrence’ that includes only temporal occurrences

… add whatever contraints are required by DTV between ‘temporal occurrence’ and ‘what-happens state of affairs’, which are adopted from SBVR …

In clause 16.7, in the entry for ' situation model occurs now', ADD a Nole:
Note: The statement “the state of affairs has an occurrence that is current” is semantically equivalent to the SBVR characterisitc “state of affairs is actual”.

The SBVR-RTF has decided not to add support for 'occurrence' or 'what-happens state of affairs' to SBVR, leaving them entirely to the Date-Time Vocabulary. Therefore, the DTV FTF-2 has chosen to retain the original Date-Time approach to these concepts but adapt them to more closely align them with SBVR. The following changes are made by this issue resolution:
1. 'Situation model' is renamed 'situation kind' on the belief that this term is more acceptable to business users, and that it is a better match to the intended meaning. 'Individual situation model' and 'general situation model' are renamed to 'individual situation kind' and 'general situation kind' to match.
2. 'Situation kind' and 'occurrence' are redefined as specializations of SBVR 'state of affairs', thus defining the relationship between SBVR 'state of affairs' and these DTV concepts.
3. The SBVR Necessity ' Each proposition corresponds to at most one state of affairs.' is replaced with ' Each proposition corresponds to exactly one situation kind.' because the original SBVR Necessity prevents a proposition from having multiple occurrences.
4. A Necessity is added to make clear that 'occurrences' are 'actual' iff they are current.
5. A Necessity is added to make clear that a 'situation kind' is actual iff there exist occurrences of the situation kind at the current time.
6. The relationship of verb concepts and verb concept objectification with 'state of affairs', 'situation kind', and 'occurrence' is described.
7. An unused Date-Time concept is removed to improve the alignment with SBVR:
situation model is realized
8. The 'proposition describes situation model' is dropped in favor of SBVR's 'proposition corresponds to state of affairs'.
Examples are used to explain how and why the Date-Time Vocabulary differs from SBVR with respect to 'states of affairs'.

This resolution also addressed most of the concerns raised by issues 16664, 16678, 16768, and 17597:

• 16664 raises a number of issues about the relationship of 'situation kind' and 'occurrence' to 'state of affairs', about when a proposition is true, and related concerns. These issues are all resolved here.
• 16678 asked for a better integration with SBVR 'state of affairs' and 'state of affairs is actual'. This resolution addresses that concern in detail.
• 16768 also asked for a better integration with SBVR 'state of affairs'.
• 17597 asked for a reorganization of the 16.1 and 16.1.1 headings. That reorganization is made in this resolution.