Date-Time Vocabulary Avatar
  1. OMG Specification

Date-Time Vocabulary — All Issues

  • Acronym: DTV
  • Issues Count: 33
  • Description: All Issues
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All Issues

Issues Summary

Key Issue Reported Fixed Disposition Status
DTV13-75 DTV 1.2 issue: Ordinals DTV 1.1 DTV 1.3 Resolved closed
DTV13-66 Use of 'week' vs. 'ISO week' in clause 10 DTV 1.1 DTV 1.3 Resolved closed
DTV13-65 missing OCL DTV 1.1 DTV 1.3 Resolved closed
DTV13-2 DTV 1.2 issue: incorrect character styling DTV 1.1 DTV 1.3 Resolved closed
DTV12-71 Necessities should be independent of placement DTV 1.1 DTV 1.2 Resolved closed
DTV12-70 Confusion of Axioms and Verb Concepts for Time Interval operations DTV 1.1 DTV 1.2 Resolved closed
DTV12-72 Occurrence does not specialize Situation Kind DTV 1.1 DTV 1.2 Resolved closed
DTV12-77 DTV Issue: Annex G: "OWL/UML Diagrams" DTV 1.1 DTV 1.2 Resolved closed
DTV12-76 There is no 'index origin element' DTV 1.1 DTV 1.2 Resolved closed
DTV12-75 ad-hoc time tables reference the same situation kind for all the time table entries DTV 1.1 DTV 1.2 Resolved closed
DTV12-74 DTV Issue: situation kind1 ends before situation kind2 DTV 1.1 DTV 1.2 Resolved closed
DTV12-73 week-of-year to day-of-year conversions ignore overlap DTV 1.1 DTV 1.2 Resolved closed
DTV12-81 Different 'time period' concept in Annex C DTV 1.1 DTV 1.2 Resolved closed
DTV12-80 member has index in sequence has no result DTV 1.1 DTV 1.2 Resolved closed
DTV12-79 Clause 7.17 is misplaced DTV 1.1 DTV 1.2 Resolved closed
DTV12-78 No indefinite time point sequences DTV 1.1 DTV 1.2 Resolved closed
DTV12-117 Why not fractional months? DTV 1.1 DTV 1.2 Resolved closed
DTV12-122 “stubs” at the beginning and end of a regular time table needed DTV 1.1 DTV 1.2 Duplicate or Merged closed
DTV12-121 what is the year of weekdays? DTV 1.1 DTV 1.2 Resolved closed
DTV12-120 The mythical 'weeks scale' DTV 1.1 DTV 1.2 Resolved closed
DTV12-119 time scale differs from time scale by time offset DTV 1.1 DTV 1.2 Resolved closed
DTV12-118 the Convention du Metre is not a time interval DTV 1.1 DTV 1.2 Resolved closed
DTV12-130 DTV Issue: OCL in clause 8.2.1 DTV 1.1 DTV 1.2 Resolved closed
DTV12-129 Status of Annex F: Simplified Syntax for Logical Formulations DTV 1.1 DTV 1.2 Resolved closed
DTV12-133 Issue: misplaced Synonymous Forms on 'time set' DTV 1.1 DTV 1.2 Resolved closed
DTV12-136 definition of compound time coordinate is circular DTV 1.1 DTV 1.2 Duplicate or Merged closed
DTV12-135 Starting week day is a number DTV 1.1 DTV 1.2 Duplicate or Merged closed
DTV12-137 time point sequences specify time periods DTV 1.1 DTV 1.2 Resolved closed
DTV12-134 Gregorian years before 1600 have no starting day DTV 1.1 DTV 1.2 Resolved closed
DTV12-132 add 'time interval starts during time interval' DTV 1.1 DTV 1.2 Resolved closed
DTV12-140 misplaced paragraph in 10.6.3 DTV 1.1 DTV 1.2 Duplicate or Merged closed
DTV12-139 Figures in 10.7 do not match the text DTV 1.1 DTV 1.2 Resolved closed
DTV12-138 Missing and incorrect text in clause 10.6 DTV 1.1 DTV 1.2 Resolved closed

Issues Descriptions

DTV 1.2 issue: Ordinals

  • Key: DTV13-75
  • Legacy Issue Number: 19734
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    These errors/typos occur in Annex D.2.6 “Ordinals”, of the dtc/2015-03-02 version of DTV 1.2:

    · The synonym for “eleventh member” is given as “third”; it should be “eleventh”.

    · All the ordinals are given as “General Concept: thing”; they should be “General Concept: member” for consistency with the names of these ordinals. “First member” in Annex D.2. should also be “General Concept: member”. (Comment: “member” is “General Concept: thing” in D.2.2. Making the ordinals “General Concept: member”, clarifies that the ordinals only apply to things that are members of unique sequences, not to things in general.)

  • Reported: DTV 1.1 — Sun, 15 Mar 2015 04:00 GMT
  • Disposition: Resolved — DTV 1.3
  • Disposition Summary:

    Clarify the "Nth member" concepts in D.2.6

    'member' is a 'role', it is not a 'general concept', so it cannot be the text of a General Concept paragraph. But the concept 'second member' does specialize the (role) concept 'member', which is the point of the issue. The text is changed to state this.

    The clarification concern is valid. The problem is that 'second member' itself has no Definition; and is separated in the text from the verb concept that implicitly defines it. The text is reorganized to place the role declaration immediately before the verb concept to supply a Definition.

  • Updated: Tue, 12 Jul 2016 14:45 GMT

Use of 'week' vs. 'ISO week' in clause 10

  • Key: DTV13-66
  • Legacy Issue Number: 19744
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    DTV v1.2 changed the model of the 'week' concept to distinguish the 'ISO week' concept. Several vestigial uses of 'week' in clause 10 should be corrected:

    • In clause 10.4, in the entry for finite time scale subdivides time point kind', the Note refers to 'day of week', which should be 'ISO day of week'.
    • In the introduction to clause 10.6, the example 'week 41 day 6' should be 'ISO week of year 41 ISO day of week 6' (really?, this wording has no business use).
    • In 10.6.3, under atomic time coordinate, the example "calendar week 53" should probably be "ISO week of year 53".
    • In 10.6.3, under 'atomic time coordinate uses index', the references to 'week of year' and 'day of week' should use "ISO".
    • In clause 10.7 (Time sets), the introduction twice refers to 'week of year' and 'weekday of year', which should use "ISO"
    • Clause 10.10 makes several references to the "year of weeks" and "week-based year", which should use "ISO"

    Also, the concept 'ISO weekday of year' in clause 12 appears to mean 'day of ISO week-based year', but that characterization in so many words does not appear in the description of the time scale or the time point. The time coordinate may have the (compound) week/day form described in clause 18, or the ungainly form noted above, but the time point only has an index, and the term 'weekday' (without the solidus) is misleading.

  • Reported: DTV 1.1 — Fri, 17 Apr 2015 04:00 GMT
  • Disposition: Resolved — DTV 1.3
  • Disposition Summary:

    Correct references to 'week' terms in Clause 10

    Correct clause 10 as indicated. Revise introduction to clause 10.7. Add a Note to 'weekday of year' in Clause 12.

  • Updated: Tue, 12 Jul 2016 14:45 GMT

missing OCL

  • Key: DTV13-65
  • Legacy Issue Number: 19743
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: Date Time Vocabulary

    Version: v1.2

    Title: missing OCL

    Summary:

    The following DTV axioms have SBVR and CLIF formulations but no OCL formulation

    1. In clause 8.3.2, under ‘duration = duration plus duration’, in Axiom V.1

    2. In clause 8.3.2, under ‘duration = number times duration’, in Axiom V.8, first Corollary

    3. In clause 8.3.2, under ‘duration = number times duration’, in Axiom V.8, 2nd Corollary

    4. In clause 8.3.2, under ‘duration = number times duration’, in Axiom V.8, 3rd Corollary

    5. In clause 16.3, under ‘occurrence occurs for occurrence interval’

    6. In Annex D.2.3, under ‘sequence has index origin value’

    7. In Annex D.3.1, under ‘quantity has quantity kind’

    Note: This is a follow-on to Issue 19462

  • Reported: DTV 1.1 — Fri, 17 Apr 2015 04:00 GMT
  • Disposition: Resolved — DTV 1.3
  • Disposition Summary:

    Supply missing OCL Definitions and Axioms in Clauses 8, 16, Annex D

    The missing OCL text is added. Some entries are reworked to align the formulations. Note that some of the CLIF Axioms only state that the arguments of particular predicates have particular types, which is conveyed by the UML signatures of the operations for OCL.

  • Updated: Tue, 12 Jul 2016 14:45 GMT

DTV 1.2 issue: incorrect character styling

  • Key: DTV13-2
  • Legacy Issue Number: 19733
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    The following Synonymous Forms have incorrect character styling: although the roles appear to have ‘term’ styles, in fact they are styled in some other way:

    time point2 follows time point1

    time point2 is next after time point1

    time point starts time interval

    time point ends time interval

    time scale of calendar

    time scale on calendar

  • Reported: DTV 1.1 — Mon, 16 Mar 2015 04:00 GMT
  • Disposition: Resolved — DTV 1.3
  • Disposition Summary:

    Repair the formatting of the cited entries

    Of the cited synonymous forms, all but one were apparently corrected in the formal text of version 1.2. The exception: "time point ends time interval" is repaired here.

    Note: this was corrected by in Ballot #1, but subsequently confused by inconsistencies in the v1.2 convenience documents.

  • Updated: Tue, 12 Jul 2016 14:45 GMT

Necessities should be independent of placement

  • Key: DTV12-71
  • Legacy Issue Number: 19516
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV

    Version: 1.1

    Source: Ed Barkmeyer, NIST, edbark(at)nist.gov

    Summary:

    In the Date Time Vocabulary v1.0 specification, clause 16.5 contains the following terminological entry:

    individual situation kind has occurrence interval

    Definition: the occurrence interval is the time span of the individual situation kind

    Necessity: The individual situation kind has exactly one occurrence

    ...

    In the Necessity, "the individual situation kind" is intended to refer to whatever plays the 'individual situation kind' role in an instance of the verb concept (wording). But that interpretation can only be made when the Necessity appears in the verb concept entry. SBVR practice is to make the meaning of the Necessity independent of where it is stated. To be consistent with SBVR practice, the above Necessity should read:

    Each individual situation kind that has an occurrence interval has exactly one occurrence.

    There are several Necessities in DTV that use this dubious form of reference. Each of them should be reformulated in the SBVR location-independent style.

  • Reported: DTV 1.1 — Fri, 11 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    After consultation with SBVR experts (see SBVR Issue 19361), the RTF agrees.
    There is a standard pattern to the revised Necessity statements. The pattern is:
    Each <subject> that <rest of verb concept wording> <rest of Necessity>.
    For the example given, the result is:
    Each individual situation kind that has an occurrence interval has exactly one occurrence.
    This pattern is applied to binary verbs, but it does not work well for ternary verbs, and other approaches were used to phrase those Necessities correctly.
    Some of the Necessities about occurrence intervals were redundant, because they were implied by the corresponding Necessities for time intervals.
    Several occurrences of the problem were omitted from this resolution because another issue corrects the same text.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Confusion of Axioms and Verb Concepts for Time Interval operations

  • Key: DTV12-70
  • Legacy Issue Number: 19628
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: Confusion of Axioms and Verb Concepts for Time Interval operations

    Summary:

    In clause 8.2.5, there are two versions of Axiom Sum, but they seem to say mostly the same thing. There is a typo: t2+t2 in the first Axiom Sum.

    The two definitions of 'time interval1 to time interval2 is time interval3' conflict – the first half of each should be a condition.

    In clause 8.2.6, what starts as Axiom Start-complement becomes a verb concept declaration that somehow has a corollary. Similarly Axiom End-complement, and for Axiom Intersection in 8.2.7. This seems to be primarily a text organization problem, but there is no Necessity and no OCL Constraint for each of the Axioms.

  • Reported: DTV 1.1 — Thu, 2 Oct 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    In 8.2.5, remove the duplicate Axioms, rewrite the Definition of ‘sum’ to be the first two ‘Corollaries’, and change the multiple ‘Definitions’ and ‘CLIF Definitions’ of sum to SBVR Necessities and CLIF Axioms.
    In 8.2.5 merge the two partial definitions of ‘time interval1 to time interval2 specifies time interval3’ to one corrected definition.
    In 8.2.6, reorganize the axioms and corollaries to follow the definition of the verb concepts, and correct the SBVR definitions of the verb concepts.
    In 8.2.7, reorganize the axioms and corollaries to follow the definition of the verb concept, and correct the definitions of the verb concept.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Occurrence does not specialize Situation Kind

  • Key: DTV12-72
  • Legacy Issue Number: 19527
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: Occurrence does not specialize Situation Kind

    Summary:

    In clause 16.3, in the entry for ‘occurrence occurs for occurrence interval’, the verb concept is said to have

    General Concept: situation kind occurs for time interval

    This would require that ‘occurrence’ specializes ‘situation kind’, which is not the case. This General Concept declaration should be deleted.

  • Reported: DTV 1.1 — Thu, 17 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Agreed. Delete the General Concept declaration.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

DTV Issue: Annex G: "OWL/UML Diagrams"

  • Key: DTV12-77
  • Legacy Issue Number: 19589
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    DTV Informative Annex G contains a set of UML diagrams of the OWL mapping of DTV. There are two problems with this Annex: (1) it is out-of-date with respect to the informative OWL ontologies that were included in DTV 1.1; (2) the set is incomplete with respect to the DTV 1.1 OWL. The diagrams should be updated or the Annex should be deleted.

  • Reported: DTV 1.1 — Thu, 28 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Since the scope of the Annex is only the supporting concepts in Annex D, as opposed to the DateTime concepts, the RTF determined that its relevance to the DTV specification is marginal. Since it is no longer accurate even for Annex D, the RTF agrees to delete the Annex.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

There is no 'index origin element'

  • Key: DTV12-76
  • Legacy Issue Number: 19590
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    The term 'index origin element' is used in several places in clauses 10-13.

    This term is not defined. The term defined in Annex D is 'index origin member', and it should be substituted for all occurrences of 'index origin element'.

  • Reported: DTV 1.1 — Thu, 28 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees

  • Updated: Wed, 8 Jul 2015 11:40 GMT

ad-hoc time tables reference the same situation kind for all the time table entries

  • Key: DTV12-75
  • Legacy Issue Number: 19652
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    Experience with FIBO reveals two problems with the way schedules are defined in DTV:

    1. DTV schedules that are based on ad-hoc time tables reference the same situation kind for all the time table entries. This is a problem because financial contracts that use ad-hoc time tables need to specify a unique situation kind for each entry.

    For example a step-up bond pays different interest rates for different periods. An ad-hoc time table can adequately represent the different periods, but each interest rate needs to be a distinct situation kind – which is not possible in the current design.

  • Reported: DTV 1.1 — Sun, 2 Nov 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees with the problems raised by these issues. Their resolution requires reworking both the DTV ‘schedule’ and ‘time table’ concepts, because:
    • The time table concept was created to support the schedule concept but it does not properly support the business concept of ad hoc schedules. As defined, there are two kinds of ‘time table’ (‘regular’ and ‘ad hoc’) and one kind of ‘schedule’ that has a single general situation kind.
    • What is needed is two kinds of ‘schedule’, one of which associates a single situation kind with a regular time table, and the other associates multiple situation kinds, each with its own time period.
    • Also, the existing ‘regular time table’ is defined as a set of time periods, when what is really needed is a starting time, a repeat count, and a repeat interval.
    To solve these problems, the RTF is forced to entirely replace the original ‘schedule’ design.
    The resolution of issue 19653 is merged into this solution because the two issues are intimately connected. This resolution adds the ‘schedule stub’ idea.
    A verb concept 'time interval1 starts after time interval1' is added to clause 8.2.4 to simplify the definition of 'schedule has earliest time'.
    A synonym is added for DTV ‘situation kind’ to match the designation of the equivalent concept in FIBO.
    A verb concept "set1 is set2 plus element" is added to a new Annex D.2.6 to support the definition of regular schedules.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

DTV Issue: situation kind1 ends before situation kind2

  • Key: DTV12-74
  • Legacy Issue Number: 19714
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    The definition of “situation kind1 ends before situation kind2” depends upon a verb concept “time interval1 ends before time interval2” that does not exist. Probably it should use “time interval1 ends after time interval2” – and the “situation kind” version should use the same verb symbol for consistency and clarity.

  • Reported: DTV 1.1 — Wed, 28 Jan 2015 05:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agreed to create the synonymous form for “time interval1 ends before time interval2”. The situation kind verb and the related occurrence verb are parallel and both provide the corresponding synonymous form.
    A typographical error in the OCL is also corrected.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

week-of-year to day-of-year conversions ignore overlap

  • Key: DTV12-73
  • Legacy Issue Number: 19650
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 12.5, the very first Necessity reads:
    " Necessity: Each week of year shares the Gregorian year of days scale with each Gregorian day of year."

    According to 10.9 that means that each week of year corresponds to some time point sequence in Gregorian day of year. This is not possible. The week of year scale has 53 time points and any given Gregorian year has either 52 weeks (364 days) or 53 weeks (371 days). So, in a year that has 53 weeks, there must be at least 5 days that have no counterpart.

    Even in a 52-week year, the first and last weeks of the year may include days from the prior or following year. The mapping to day of year can work, but not necessarily to days of the same year; one must consider the repeating aspect, and time point sequences that wrap around the end of the finite scale. For example, week of year 1 can convert to day of year 364, 365, 1, 2, 3, 4, 5, if the year begins on Wednesday. If that is a valid 'time point sequence' on the year of days scale, then the rules given for the conversions in clause 12.5 do not support it.

  • Reported: DTV 1.1 — Thu, 30 Oct 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The Necessity is false. The problem is not overlap; the time point sequence can wrap around the end of the Gregorian day of year scale. The problem is that there is no single time point sequence on the Gregorian year of days that corresponds to the same time intervals as any given week of year (see 10.9). Both Necessities following Figure 12.4 are false. Some of the Examples are true, but only because they fall outside the related time sets. They have nothing to do with sharing the time scale.
    Similarly, the conversion to time sets on the year of days scale is misleading, because the wrap around the end of the Gregorian year of days causes the time points to refer to time periods in different Gregorian years. So, it would be necessary to add additional rules to explain the complex correspondences of the time sets to time intervals.
    The intent of this section cannot be preserved. The generic relationships between the year of weeks and the Gregorian year of days are defined by the year of weeks itself. There are no others. When the Gregorian year is given, the specific correspondences can be determined from the common Gregorian days scale, on which all of them are based.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Different 'time period' concept in Annex C

  • Key: DTV12-81
  • Legacy Issue Number: 19517
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV

    Version: 1.1

    Title: Different 'time period' concept in Annex C

    Source: Ed Barkmeyer, NIST, edbark(at)nist.gov

    Summary:

    In the Date Time Vocabulary v1.1 specification, Annex C contains the following terminological entries:

    fixed period

    Definition: time period that cannot be changed

    ...

    variable period

    Definition: time period that can be rescheduled

    In DTV clause 8.7, a time period is defined to be: time interval that instantiates some time point sequence

    No time interval can ever "be changed" , at least not in the sense of "modified". And similarly, time intervals are unlikely to be "rescheduled". One cannot alter the time interval designated July 25 into some other time interval, nor can one meaningfully reschedule it.

    The intent here seems to be that some kind of schedule entry can be changed or an event can be rescheduled, so that the entry refers to a different time interval. Therefore, the term 'time period', as used in Annex C.3, does not have the meaning given in 8.7.

    SBVR Annex A.2.6 discusses verbs of change and the idea of intensional roles. But in DTV Annex C, fixed period and variable period are apparently being defined as general noun concepts. (On the other hand, 'scheduled start time' is a role that is apparently declared to be a general concept.) It may be that the business use of 'time period' IS often a role of time interval, or a schedule entry that refers to a time interval, and that the DTV use of the term is not business-friendly.

  • Reported: DTV 1.1 — Fri, 11 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    In response to Issues 18990 and 19336, the RTF decided to replace the current EU Rent example in Annex C with some examples drawn from actual business experience. So this issue is moot. Formally, it can be said to be resolved via Issue 19336

  • Updated: Wed, 8 Jul 2015 11:40 GMT

member has index in sequence has no result

  • Key: DTV12-80
  • Legacy Issue Number: 19550
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In Annex D.2.2, the entry for ‘member has index in sequence’ has a main sentential form and two Synonymous noun Forms that are followed by definitions of CLIF functions and OCL operations. The first Note reads:

    The primary verb concept and the synonymous form given above are “sentential forms” that yield a Boolean result.

    A verb concept is not a sentential form and it does not “yield a boolean result”. What is meant is that the verb concept wording is a sentential form, and the corresponding CLIF predicate and the OCL operation yield a boolean result. This pattern must be true of many other verb concepts in the vocabulary. It is strange that it first appears in an Annex.

    The Definition can be simplified to: Some sequence position of the sequence has an index that is equal to the index and has a member that is the member.

    In addition, one of the synonymous forms has inconsistent type setting.

  • Reported: DTV 1.1 — Mon, 28 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Reword the Note to say that the CLIF predicate and the UML/OCL operation derived from the primary wording yield a Boolean result, while those derived from the noun forms return the index value or the member.
    The CLIF and OCL relations for index of member in sequence, however, have no corresponding function. The only things that have indices in a sequence are those that are members of exactly one sequence position in the sequence. So the would-be ‘function’ is not defined on ‘thing’. This ‘noun form’ is therefore deleted. The only use of it is in the definition of ‘time point has index’. That definition is corrected. All the rest of the uses in the text are as ‘index of time point’.
    The wording of an introductory paragraph to Section D.2 (Sequences) is somewhat misleading about the relationship of time points and time intervals to indices. It is revised.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Clause 7.17 is misplaced

  • Key: DTV12-79
  • Legacy Issue Number: 19573
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Clause 7.17 is an overview of the specification structure. It is incorrectly placed at the end of Clause 7 (Rationale). It should be in Clause 6, following 6.3, which gives an overview of the specification.

  • Reported: DTV 1.1 — Mon, 11 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The issue is correct. The clause was inadvertently separated from Clause 6 when the Rationale section was added. It is moved back to follow 6.3.
    Note: Issue 19483 revises the Figure in clause 7.17 and some of the descriptive text. So, that revision is merged with this Issue.
    Note: Issue 19574 renames the ‘Week Calendar’ package to ‘ISO Week Calendar’ and that change is included in Figure 6.1 below.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

No indefinite time point sequences

  • Key: DTV12-78
  • Legacy Issue Number: 19546
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 8.7, the definition of time point sequence corresponds to time interval assumes that each time point sequence has a first time point and a last time point. Further, v1.1 introduced the “time points” primordial and perpetuity to provide the means for specifying indefinite time periods. That creates time points to be the first and last time points of the time point sequences that correspond to indefinite time periods.

    We must either redefine the correspondence concept or remove the possibility that there is no first/last time point. The latter simplifies the model. (Note also that most indefinite time periods DO have a last time point, we just don’t know what it is.)

  • Reported: DTV 1.1 — Fri, 25 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that indefinite time point sequences are problematic. The text should recommend the use of ‘primordial’ and ‘perpetuity’ when those are explicitly intended. But when the first or last time point of a time point sequence is simply “unknown”, that is not clearly appropriate. In any case, however, every time point sequence has a first time point and a last time point, and the text is revised to eliminate features and wording that suggest otherwise.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Why not fractional months?

  • Key: DTV12-117
  • Legacy Issue Number: 19531
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 9.3, in the entry for 'duration value equals number times duration value', we find the Necessity:

    Necessity: If duration value1 is a nominal duration value and the number is fractional then the time unit of each atomic duration value of the duration value is not ‘month’ and the fractional part of the number is ¼, ½, 2/4, or ¾.

    This Necessity, the four Necessities that follow, and the Note that follows them, are constraints on the number part of a nominal duration value. They are not necessities about scalar multiplication. At best all of this should be moved to 9.2.3.

    This necessity, however, is unnecessarily restrictive, and appears to be utterly inappropriate. 1/3 year is 4 months, 1/6 year is 2 months, and 1/12 year is 1 month, and their multiples are multiples of months, but they are apparently "not common in business usage". Moreover, in estimating a contract, why couldn’t one multiply a standard duration estimate stated in months by 1.2 to allow for some delaying factor? And similarly, if we average seven durations stated in years, the multiplier is 1/7. Business analytics will generate fractional multiples of months and years. Why should DTV disallow them?

    The Note provides the underlying motivation:

    Note: This specification defines only the fractional nominal duration values ¼ year, ½ year, 2/4 year, and ¾ year because these are in common business use and they equal an integral number of months. This specification does not support any fractional 'month' duration values

    because such fractions are not in common use [which is false] and because they are not equal to an integral number of years or days [which is the real reason].

    Integral number of months or years are not equal to an integral number of days, either. But, per 9.2.3, they correspond to time sets (in days), while a fractional number of either does not. How important is this?

  • Reported: DTV 1.1 — Fri, 18 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that the cited Necessity is an unnecessary constraint. It is deleted, and the subsequent Note is revised.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

“stubs” at the beginning and end of a regular time table needed

  • Key: DTV12-122
  • Legacy Issue Number: 19653
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    DTV schedules that are based on regular time tables need a way to model “stubs” at the beginning and end of a regular time table. These stubs are time periods that fall immediately before or after the time span of the regular time table. They capture any special handling that is required before the start or after the end of the regular portion of the schedule.

    A typical financial example is a home mortgage where payments are due at the start of each calendar month. If the mortgage is initiated in the middle of a calendar month, then there will be an initial payment, covering the period to the beginning of the next calendar month. Similarly, there may be a final payment for the days after the last monthly payment. As currently defined, a DTV schedule that uses a regular time table can model the regular monthly mortgage payments. But DTV has no provision for the “stub” initial and final payments.

    These two problems should be fixed in order to make DTV schedules usable for typical financial contracts.

  • Reported: DTV 1.1 — Sun, 2 Nov 2014 04:00 GMT
  • Disposition: Duplicate or Merged — DTV 1.2
  • Disposition Summary:

    The RTF agrees to add the requested feature. The resolution is merged with that of issue 19652 since the latter replaces the affected clause.

    Disposition: Merged (see Issue 19652)

  • Updated: Wed, 8 Jul 2015 11:40 GMT

what is the year of weekdays?

  • Key: DTV12-121
  • Legacy Issue Number: 19645
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: Date Time Vocabulary v1.1

    Title: what is the year of weekdays?

    Summary:

    In clause 12.2, the year of weekdays is defined as:

    Definition: the finite time scale that has granularity 1 day and that has cardinality 366 and that repeats over the year of days scale

    Since the year of days also has 366 time points, it is impossible that the year of weekdays can repeat over it. The intent must be that it repeats over the Gregorian days scale. But that also describes the year of days scale. So it is inadequate.

    The Necessity provides the real delimiting characteristic:

    Necessity: Each time interval that is an instance of the first time point of the year of weekdays is a Monday and is an instance of a day of year that has an index that is less than 8.

    Now, if the intent is that the year of week days goes from the first Monday of one year to the Sunday before the first Monday of the following year (which is not at all clear from the above), then the scale must have 371 (7 x 53) time points, because a year that starts on a Monday ends on a Monday, and the first Monday of the following year is 6 days later.

    This structure has no relationship to the year of weeks calendar, because the year of weeks starts with the Monday of the week that contains the first Thursday, and 3 times in 7 years, the year of weekdays will begin in week of year 2.

    So, what (and why) is the 'year of weekdays'?

  • Reported: DTV 1.1 — Tue, 21 Oct 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The year of weekdays is intended to provide a subdivision of the “week-based year” that is defined by the year of weeks time scale, in order to support relative time coordinates of the week-day form. For that intent, the existing Definition and Necessity are incorrect.
    The ISO week-based year concept is introduced in parallel to the Gregorian year, and the weekday of year concept is then defined as a “day of ISO week-based year”.
    The revised text below incorporates terms from the resolution to Issue 19574.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

The mythical 'weeks scale'

  • Key: DTV12-120
  • Legacy Issue Number: 19574
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    DTV defines the indefinite 'weeks scale' in clause 12.2 as follows:

    Definition: indefinite time scale of granularity 'week' and of 'calendar week' time points

    Note: No special meaning is assigned to the indices of calendar weeks on the week scale. Therefore, no index origin element or index origin value is specified for this time scale.

    It then defines calendar week as follows:

    Definition: time point that is on the weeks scale and that is defined by a given calendar as 7 consecutive calendar days

    Note: ISO 8601 adds “starting on a Monday” to this definition. This vocabulary drops that phrase because it is culture-specific.

    The net effect of these is that weeks are some sequences of 7 days that are determined by a calendar. We don’t know where any such sequence begins, or what day-of-week it begins with. There is no significance to the indices because none of them is defined to refer to any particular point in time. So, DTV does not define a specific ' weeks scale' at all.

    Now, clause 12.1 says: "References to specific weeks are by week of year coordinate. This specification follows [ISO 8601] in defining 'Monday' as the first day of the week." This contradicts the above. But it does confirm that the finite 'year of weeks' scale is the only well-defined scale whose granularity is a week.

    Then in 12.4 we find this entry:

    year week coordinate indicates time point sequence

    Definition: the Gregorian year coordinate and the week of year coordinate of year week coordinate jointly specify a time point sequence of Gregorian days

    Note: Unlike other time coordinates, this one indicates a time point sequence, not a time point. This is because a year week coordinate means a sequence of calendar days rather an individual time point on some time scale.

    So a 'year week coordinate' does not refer to a 'week' on any 'weeks scale' . Now, since it does not indicate any time point, a year-week coordinate is NOT a time coordinate.

    The presented model is incomplete and inconsistent. The underlying model anchors a weeks scale to Gregorian days – every instance of a Gregorian day instantiates a particular day-of-week; and the relationship to Gregorian years is dependent on choosing Monday as the first day of week. It is absolutely necessary to anchor some day-of-week to some event or time interval, in order to have any idea which Gregorian days are Mondays. Somewhere in the text, it is mentioned that January 1, 2000 is a Saturday. (More useful is the fact that January 1, 1601 is a Monday.) And that, together with the assertion that Monday is the first day of a week-of-year, defines a weeks scale, except for assigning an index to the week containing January 1, 2000 (or 1601).

  • Reported: DTV 1.1 — Tue, 12 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The underlying problem here was the unwillingness of the FTF to commit to Monday as the first day of the week, as indicated in the cited Note. The assertion in 12.1 did not represent consensus of the RTF. As a consequence, the Week Calendar Vocabulary, and most of the terms introduced in the section, are now prefixed by “ISO” to distinguish them from weeks calendars that choose other conventions for the first day of the week. At the same time, the neutral concepts ‘calendar week’ and ‘week period’ are retained and moved to Clause 10 to support the original purpose of allowing other choices for first day of week.
    Establishing Monday as day of week 1 enables the specification of a reference time period for an index origin member for the indefinite weeks scale, choosing Monday, January 3, 2000, with an index consistent with the Gregorian day numbering.
    Aligning the Gregorian calendar with the weeks calendar eliminates the need for the verb concept ‘year week coordinate indicates time point sequence’ and the related ‘starting week day’ idea, which are deleted. In its place, we create the ‘starting week’ concept, which is parallel to ‘starting day’. This enables the correct axioms (Necessities) for the year of weeks and year of weekdays scales.
    Some related errors in terminology or arithmetic are also corrected.
    The RTF determined in resolving Issue 19525 that the definition of ‘starting day’ should be functional and the calculation should be a Necessity. The same idea is applied to ‘starting week’.
    Issue 19034 recommended editorial corrections to the terms for day of week time points. These are included in the modifications to the (ISO) day of week entry below.
    Issue 19526 asked for corrections to the description of ‘starting weekday’, which this resolution deletes. But the definition of ‘starting week’ requires the notion ‘first Thursday’, which was embedded in the ‘starting week day’ concept. So the revised text carries the intent of Issue 19526 forward.
    The resolution to Issue 19645 modifies the entry for the year of weekdays scale and incorporates text changes related to this issue. It also adds the concept ISO week-based year, which is mentioned in the revised introductory text below.
    The resolution to Issue 19650 deletes section 12.5. Nomenclature changes in 12.5 that are related to this issue are therefore omitted below.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

time scale differs from time scale by time offset

  • Key: DTV12-119
  • Legacy Issue Number: 19572
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 10.5, Figure 10.7 is titled Time Zones, and it shows a verb concept: “time scale differs from time scale by time offset”. This verb concept is in the UML model (in Time Infrastructure), but does not appear anywhere in the text of DTV v1.1. It appears to have been replaced by ‘calendar1 differs from calendar2 by time offset’ in Figure 10.8. But Figure 10.7 shows several other concepts that are defined in clause 10.5, and the definition of ‘local calendar’ refers to a time scale that “differs from the UTC day-of-hours time scale by a given time offset”, which appears to use the phantom verb concept.

  • Reported: DTV 1.1 — Thu, 7 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The UML diagram will be realigned with the text. The definition of ‘local calendar’ and the definitions of time coordinates ‘with time offset’ are modified to use the documented verb concept ‘calendar1 differs from calendar2 by time offset’.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

the Convention du Metre is not a time interval

  • Key: DTV12-118
  • Legacy Issue Number: 19566
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In DTV clause 11.2, the entry for Convention du Métre contains:

    Definition: time interval of the signing of the Convention du Métre

    Necessity: The Convention du Métre is at 20 May 1875.

    These are inconsistent. The Necessity uses an undefined verb concept 'time interval is at time interval'.

    It was intended that the Necessity uses 'occurrence is at (during) time interval'. The signing of the treaty is not a time interval; it is an event, an occurrence. The important fact is that the signing event occurred within the day, month and year denoted by 20 May 1875.

    The conventions for establishing which time interval was named 20 May 1875 were established at that time by observation of noon at the Greenwich observatory. That was used as the basis for definition of Gregorian days until 1972, when it was replaced by Universal Coordinated Time (UTC). By convention, 24-hour periods with a midpoint at Greenwich noon might also be used to define Gregorian days before 1875, although actual approaches were different. Without specifying these conventions as well, the concept Gregorian day is not defined by the date of the Convention du Métre. There are several thousand distinct time intervals that encompass the signing of the treaty and have a duration of 86400 seconds.

  • Reported: DTV 1.1 — Fri, 1 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The Convention du Mètre is intended to be an occurrence. Inaccurate references should refer to the Gregorian day of the signing, which is properly defined as the 24 hours beginning at midnight as determined by Greenwich Mean Time from 1884 to 1972 and by UTC thereafter.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

DTV Issue: OCL in clause 8.2.1

  • Key: DTV12-130
  • Legacy Issue Number: 19703
  • Status: closed  
  • Source: General Electric ( Mark Linehan)
  • Summary:

    The only OCL Constraint in DTV clause 8.2.1 reads:

    context: _'time interval'

    inv: 'time interval'.'time interval1 is proper part of time interval2'-->notEmpty()

    It should be:

    context: _'time interval'

    inv: self._'time interval1 is proper part of time interval2'-->notEmpty()

    (The first word after the “inv:” in the second line should be “self”, not “_’time_interval’”.)

  • Reported: DTV 1.1 — Wed, 7 Jan 2015 05:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that the OCL is incorrect. Interpretation of the corrected OCL, however, seems to require any conforming M0 population of the UML/MOF model to be infinite, in that each ‘time interval’ object must have different ‘proper part’ time interval. The intent of the Axiom is that no time interval can be declared or assumed to be atomic, but in any given model population there will be time intervals that have no proper part in the population. The proposed OCL constraint would make such a population invalid.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Status of Annex F: Simplified Syntax for Logical Formulations

  • Key: DTV12-129
  • Legacy Issue Number: 19579
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    First, the notation introduced in Annex F is used nowhere in the DTV v1.1 specification. It was formerly used in Annex that was revised in DTV v1.0. The title of Annex F is confusing for DTV, since DTV provides normative logical formulations in CLIF and OCL. The intent is to describe SBVR logical formulations, for which DTV provides normative expressions in SBVR Structured English.

    Second, the Annex specifies a notation for SBVR logical formulations. If it is to have value, the notation should be specified in the SBVR specification. In any case, this Annex should be considered for adoption by the SBVR RTF (as the DTV FTF recommended). Indeed, the SBVR Logical Representation of Meaning clause might well profit from the ability to express examples in this form. There are some technical defects in the Annex F specification, but these could be remedied by the SBVR RTF, whereas specifications for the representation of SBVR are out of scope for the DTV RTF.

    Finally, the text of Annex F begins: “The table below is kindly provided by Don Baisley of Microsoft Corp.” This sentence is entirely inappropriate, and raises intellectual property concerns. If the Annex is retained, this sentence must be deleted. Don Baisley is properly included in the acknowledgements in 6.4, but the specification is the work of the submitters and the editing Task Forces, and this Annex is presumably not intended to be an exception.

  • Reported: DTV 1.1 — Thu, 14 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that the Annex should not be a part of the Date Time Vocabulary. The Issue of incorporating in SBVR has been raised to the SBVR RTF, noting that the specification in Annex F was formally adopted by the OMG.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Issue: misplaced Synonymous Forms on 'time set'

  • Key: DTV12-133
  • Legacy Issue Number: 19524
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: misplaced Synonymous Forms on 'time set'

    Summary:

    In DTV v1.1, clause 10.7, the two synonymous forms under ‘time set’

    Synonymous Form: time set1 equals time set2

    Synonymous Form: time set1 = time set2

    should be under ‘time set1 is equivalent to time set2’

  • Reported: DTV 1.1 — Wed, 16 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Agree. Editorial repair

  • Updated: Wed, 8 Jul 2015 11:40 GMT

definition of compound time coordinate is circular

  • Key: DTV12-136
  • Legacy Issue Number: 19529
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 10.6.3, the definition of 'compound time coordinate' is:

    Definition: time coordinate that combines more than one time coordinate

    and the definition of 'compound time coordinate combines atomic time coordinate' is:

    Definition: the atomic time coordinates jointly specify the compound time coordinate

    That makes them both circular. Prefer something like:

    compound time coordinate

    Definition: time coordinate that is a set of atomic time coordinates that jointly indicate a time point

    compound time coordinate combines atomic time coordinate

    Definition: the atomic time coordinate is an element of the compound time coordinate (set)

    These definitions match the first Necessity under the verb concept.

    The 'set' makes the second Necessity redundant.

    The third Necessity is misstated: it compares a time coordinate to a time scale.

  • Reported: DTV 1.1 — Fri, 18 Jul 2014 04:00 GMT
  • Disposition: Duplicate or Merged — DTV 1.2
  • Disposition Summary:

    The circular definitions are resolved more or less as suggested, and the related Necessities are revised.
    Because of other changes to the descriptions of compound time coordinates that affect the same definitions, and related changes to the UML diagrams, the revised text for this issue is merged with Issue 19547.
    Revised Text:
    See Issue 19547.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Starting week day is a number

  • Key: DTV12-135
  • Legacy Issue Number: 19526
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: Starting week day is a number

    In clause 12.4, the entry for starting week day has the Definition:

    the index of the Gregorian day of year that is 3 days before the first Thursday of some Gregorian year

    It is at least unexpected that any category of ‘day’ would be a integer. The definition appears to be that of ‘starting Monday index’, or something the like. The expected concept would be “Gregorian day that is three days before the Gregorian day that corresponds to the first Thursday of the Gregorian year.’ In either case, one would have to define: Gregorian year has first Thursday. This suggests that the useful concept is in fact, Gregorian year has starting Thursday (or starting Monday).

    The verb concept is ‘starting week day of Gregorian year’ rather than ‘Gregorian year has starting week day’, and there is a Necessity that only Gregorian years after 1600 have starting week days, which is clearly wrong.

    This whole concept appears to be an artifice for determining which week of the ‘weeks calendar’ is the ‘first week’ of a Gregorian year. So there is no intended business use of these terms, but the entries should be corrected.

  • Reported: DTV 1.1 — Thu, 17 Jul 2014 04:00 GMT
  • Disposition: Duplicate or Merged — DTV 1.2
  • Disposition Summary:

    The last paragraph of the Issue Summary correctly indicates that the function of ‘starting week day’ is to support interpretation of ‘week of year’ and ‘year week coordinates’. The resolution of Issue 19574 restructures that interpretation by creating a fixed relationship between the Gregorian calendar and the weeks calendar. That restructuring eliminates the use of ‘starting week day’ per se, although it makes a similar concept ‘first Thursday’ necessary.
    The resolution of this issue is therefore merged with that of 19574.
    Revised Text:
    none. See Issue 19574

  • Updated: Wed, 8 Jul 2015 11:40 GMT

time point sequences specify time periods

  • Key: DTV12-137
  • Legacy Issue Number: 19530
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Clause 8.7 includes two verb concepts:

    time point1 through time point2 specifies time period

    time point1 to time point2 specifies time period

    The definitions of these concepts describe the construction of a time point sequence followed by the correspondence to time period. Several of the Necessities in these entries restate Necessities for time point sequences. At least one Necessity for time point sequences in general is stated here but not in the entry for time point sequences:

    If the time scale of time point1 is an indefinite time scale then time point1 through time point2 specifies exactly one time period.

    That is, each time point sequence that is on an indefinite time scale corresponds to exactly one time period.

    By creating companion verb concepts:

    time point1 through time point2 defines time point sequence

    time point1 to time point2 defines time point sequence

    the redundancies can be eliminated and the Definitions and Necessities for the two verb concepts specifying time periods can be greatly simplified.

    E.g. for

    time point1 through time point2 specifies time period

    Definition: time point1 is the first time point of a time point sequence and time point2 is the last time point of the time point sequence and the time point sequence corresponds to the time period

    the Definition is replaced by:

    Definition: the time point sequence that is defined by time point1 through time point2 corresponds to the time period

  • Reported: DTV 1.1 — Fri, 18 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that Necessities about time point sequences in general should be moved to the entry for time point sequence or the related verb concepts.
    The RTF notes that the UML diagram in Figure 8.25 is inconsistent with the existing text, and includes the two proposed intermediate verb concepts.
    The proposed verb concepts are added, the definitions and necessities for the cited concepts are revised accordingly, and the UML model is re-aligned with the text.
    Text is added to explain that ‘time point sequence’ is overall an artificial construct used to describe references to time periods.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Gregorian years before 1600 have no starting day

  • Key: DTV12-134
  • Legacy Issue Number: 19525
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: Gregorian years before 1600 have no starting day

    Summary:

    In clause 11.7, in the entry for ‘Gregorian year has starting day’, the Definition is a formula for calculating the index of the ‘starting day’, as distinct from a definition of the verb concept (which is actually carried in the definition of the role ‘starting day’). The Definition is followed by the Necessity:

    Necessity: The index of Gregorian year is greater than 1600.

    We must conclude that either there are no Gregorian years before 1600, or the ones before 1600 have no starting day. The real intent is probably that the formula given in the Definition is not correct for Gregorian years before 1600.

    The correct definition is: The starting day is the Gregorian day that is the first calendar day of the Gregorian year.

    Necessity: Each Gregorian year has exactly one calendar day.

    Necessity: The starting day of Gregorian year 1875 is Gregorian day 684606.

    This relates the concept to the index origin for the Gregorian days scale. The rest are determined by the rules for the length of Gregorian years.

    How to compute the index of the starting day from 1601 on should be a Note. One would expect the rule to be how to calculate from the index origin, and there may be other such algorithms. The concept is not the computation algorithm.

  • Reported: DTV 1.1 — Thu, 17 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agrees that the definition should be corrected, and the first Necessity should be added.
    The Gregorian calendar algorithm is, however, a Necessity not a Note, and the starting day of 1601 is important to it. The second proposed Necessity is irrelevant – the index origin of the Gregorian days calendar is not the starting day of any Gregorian year, and is not useful to the calendar algorithm.
    Note also that there are no Gregorian years before 1582. That Necessity is corrected

  • Updated: Wed, 8 Jul 2015 11:40 GMT

add 'time interval starts during time interval'

  • Key: DTV12-132
  • Legacy Issue Number: 19521
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV

    Version: 1.1

    Source: Ed Barkmeyer, NIST, edbark(at)nist.gov

    Summary:

    Examination of some business usages of time concepts has led to the observation that several regulations use the concept:

    time interval1 starts during time interval2

    or

    occurrence starts during time interval

    These verb concepts can easily be phrased in terms of existing DTV concepts, but the phrasing is cumbersome. It would be useful to add these to the DTV business vocabulary.

  • Reported: DTV 1.1 — Fri, 11 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    The RTF agreed to add these, in order to simplify business usage.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

misplaced paragraph in 10.6.3

  • Key: DTV12-140
  • Legacy Issue Number: 19635
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Following the entry for ‘compound time coordinate combines atomic time coordinate’, the following paragraph appears:

    Calendar scales (i.e., those involving calendar years, calendar months, calendar weeks, and calendar days) use index origin value 1, while time-of-day scales (i.e., those involving hours of day, minutes of hour and seconds of minute) use index origin value 0. In all cases other than the Gregorian years scale, the index original element is the first element of the time scale. For clarity, the index origin value and index origin element of each time scale is included with the time scale.

    The paragraph has nothing to do with the nature of time coordinates, which is the topic of 10.6. It may belong in 10.8 or at the end of 10.1.

  • Reported: DTV 1.1 — Wed, 8 Oct 2014 04:00 GMT
  • Disposition: Duplicate or Merged — DTV 1.2
  • Disposition Summary:

    The paragraph is out of place, but it is most relevant to atomic time coordinates that involve the index of the time point. It is reworded to make that clear, and to clarify the forward references to clauses 11 and 13.
    The text revision is in the area modified by issues 19547 and 18991, and the corresponding text changes are merged with Issue 19547.
    Revised Text:
    see Issue 19547.

    Disposition: Merged (see Issue 19547)

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Figures in 10.7 do not match the text

  • Key: DTV12-139
  • Legacy Issue Number: 19570
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    In clause 10.7 (time sets), Figure 10.15 is followed by text that relates time sets to time point sequences, but time point sequences do not appear in the Figure. Similarly, Figure 10.16 is the same diagram, but it is followed by text that relates time sets to time periods, and time periods do not appear in the diagram.

  • Reported: DTV 1.1 — Tue, 5 Aug 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Both of these diagrams are out-of-date. They are replaced with the correct diagrams.
    Note also that Figure 10.15 correctly shows that ‘time point sequence matches time set’ specializes ‘thing is in set’. The entry is modified to capture this.

  • Updated: Wed, 8 Jul 2015 11:40 GMT

Missing and incorrect text in clause 10.6

  • Key: DTV12-138
  • Legacy Issue Number: 19547
  • Status: closed  
  • Source: Thematix Partners LLC ( Mr. Edward J. Barkmeyer)
  • Summary:

    Specification: DTV v1.1

    Title: Missing and incorrect text in clause 10.6

    Summary:

    In clause 10.6 (Time Coordinates), the introduction suggests that a time coordinate can represent more than one time point. This is false. A time coordinate represents exactly one time point (which is nowhere stated). It can only combine time point identifiers to refer to a different time point.

    The verb concept 'time coordinate has time scale' appears in the UML diagram and in one of the definitions, but nowhere in the text.

    In the entry for 'time coordinate', the two dichotomies are stated as possibilities in the Notes. They should be stated as Necessities.

    The definitions of absolute and relative time coordinates refer to their "corresponding to" time intervals. The time points correspond, but the coordinates only "refer to" them.

  • Reported: DTV 1.1 — Mon, 28 Jul 2014 04:00 GMT
  • Disposition: Resolved — DTV 1.2
  • Disposition Summary:

    Upon examination, the RTF determined that an atomic time coordinate indicates exactly one time point. A compound time coordinate, and therefore time coordinates in general, indicates at most one time point, and may not indicate any (documented) time point. For example, March 3 does not indicate any documented time point. This necessitates a number of minor changes to the model, and to the wording of many definitions in 10.6.
    With this understanding, only an atomic time coordinate has a time scale, and that concept is added.
    The dichotomies are restated as Necessities, and shown in the UML diagrams. The definitions of absolute and relative time coordinates are modified as recommended, and other inconsistencies are also repaired.
    There is a significant overlap of the changes associated with this issue and the changes associated with Issues 18989, 18991, 19529, and 19635.
    Issue 18989 and 18991 (duplicates) were resolved to determine that a time coordinate is a conceptual structure of meaning rather than a representation of a time point. This affects the UML diagrams in 10.6, the wording of the introductory text, and the wording of many of the definitions being altered by Issue 19547. In particular this results in elaborating the model of atomic time coordinate.
    Issue 18991 also makes parallel changes to the wording of Clause 9.1 and 9.2.
    Issue 19529 points out that the definitions of ‘compound time coordinate’ and ‘compound time coordinate combines atomic time coordinate’ are circular. The resolution of that issue is to define a compound time coordinate to be a set of atomic time coordinates, but to ‘combine’ time coordinates in general. The revised definitions must also take into account the fact that compound time coordinates do not necessarily indicate time points. Those changes are therefore merged into the Revised Text below.
    Issue 19635 requires an editorial change to move a misplaced paragraph in 10.6.3. In addition, the revised entry for ‘compound time coordinate includes atomic time coordinate’ is moved to follow the entry for ‘compound time coordinate’.

  • Updated: Wed, 8 Jul 2015 11:40 GMT