Issue 16997: forever is misdefined (date-time-ftf) Source: NIST (Mr. Edward J. Barkmeyer, edbark(at)nist.gov) Nature: Uncategorized Issue Severity: Summary: In clause 9.4, 'forever' is defined as: "the time period that does not start on some time point and does not end on some time point". This is interpreted "there are two time points t1 and t2 such that the time period does not start on t1 and does not end on t2". What is intended is "the time period that starts on no time point and that ends on no time point". Further, this definition does not identify any time point sequence that makes the term 'time period' appropriate, and it eliminates all described ways to define a time point sequence. It seems that 'forever' should be classified 'time interval', with the above qualifications, not 'time period'. Or perhaps the intent is: "the time period that is the instance of each time point sequence that has no first time point and that has no last time point". Also, some Note should clarify the relationship of 'forever' to the Time Axis. Clause 8.1 does not say that the Time Axis is a time interval. Is 'forever' the time interval that is the "segment of the Time Axis" that covers all of it? Or is 'forever' the same thing as the Time Axis? I.e., is the Time Axis itself a time interval and 'forever' a synonym? Resolution: Revised Text: Actions taken: January 10, 2012: received issue Discussion: End of Annotations:===== c: edbark@nist.gov Subject: Fw: DTV Issue: forever is misdefined X-KeepSent: BE7F59DA:048E7F6A-85257984:0066F060; type=4; name=$KeepSent X-Mailer: Lotus Notes Release 8.5.1FP5 SHF29 November 12, 2010 From: Mark H Linehan Date: Fri, 13 Jan 2012 13:42:25 -0500 X-MIMETrack: Serialize by Router on D01MC604/01/M/IBM(Release 8.5.2FP1 ZX852FP1HF6|May 2, 2011) at 01/13/2012 13:42:14, Serialize complete at 01/13/2012 13:42:14 x-cbid: 12011318-3534-0000-0000-000004832EA3 Juergen, I think we still need an issue number assigned for this one. Thanks. -------------------------------- Mark H. Linehan STSM, Model Driven Business Transformation IBM Research ----- Forwarded by Mark H Linehan/Watson/IBM on 01/13/2012 01:44 PM ----- From: Ed Barkmeyer To: issues@omg.org Cc: OMG DateTimeVoc FTF Date: 01/10/2012 01:39 PM Subject: DTV Issue: forever is misdefined -------------------------------------------------------------------------------- Specification: Date Time Vocabulary Version: beta-1 Title: forever is misdefined Source: Ed Barkmeyer, NIST, edbark@nist.gov' Summary: In clause 9.4, 'forever' is defined as: "the time period that does not start on some time point and does not end on some time point". This is interpreted "there are two time points t1 and t2 such that the time period does not start on t1 and does not end on t2". What is intended is "the time period that starts on no time point and that ends on no time point". Further, this definition does not identify any time point sequence that makes the term 'time period' appropriate, and it eliminates all described ways to define a time point sequence. It seems that 'forever' should be classified 'time interval', with the above qualifications, not 'time period'. Or perhaps the intent is: "the time period that is the instance of each time point sequence that has no first time point and that has no last time point". Also, some Note should clarify the relationship of 'forever' to the Time Axis. Clause 8.1 does not say that the Time Axis is a time interval. Is 'forever' the time interval that is the "segment of the Time Axis" that covers all of it? Or is 'forever' the same thing as the Time Axis? I.e., is the Time Axis itself a time interval and 'forever' a synonym? -- Edward J. Barkmeyer Email: edbark@nist.gov National Institute of Standards & Technology Manufacturing Systems Integration Division 100 Bureau Drive, Stop 8263 Tel: +1 301-975-3528 Gaithersburg, MD 20899-8263 Cel: +1 240-672-5800 To: date-time-ftf@omg.org Subject: Date-Time Issues 17540, 16992, 16993, 16997 - indefinite time intervals X-KeepSent: F730BBD9:97319387-85257A71:0012AAA4; type=4; name=$KeepSent X-Mailer: Lotus Notes Release 8.5.3 September 15, 2011 From: Mark H Linehan Date: Wed, 5 Sep 2012 23:30:47 -0400 X-MIMETrack: Serialize by Router on D01ML604/01/M/IBM(Release 8.5.3FP2IF1|July 25, 2012) at 09/05/2012 23:30:49 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12090603-7182-0000-0000-00000282D100 This set of four proposed resolutions addresses the issues around "indefinite" time intervals. They are based on today's discussion between Mike and I. 17540 adds concepts 'primordial' and 'perpetuity' and renames & redefines 'forever' as 'eternity'. (I am not crazy about these terms, particularly 'primordial', which is an adjective.) 16993 adds verb concepts such as 'time interval through occurrence'. 16997 is a duplicate of 17540. 16992 is mostly about durations, but was blocked by 17540. This version rewrites the Notes proposed to be added to 'time interval'. During conversation, we thought the last two Corollaries need some change, but on further review I think they are ok as proposed. ----------------------------- Mark H. Linehan STSM, IBM Research Date-Time Issue 16992- Corollaries to Axiom D.4 in 8.2.3 are misstated.doc Date-Time Issue 16993 - no syntax for indefinite time periods.doc Date-Time Issue 16997 - forever is misdefined.doc Date-Time Issue 17540 - Need to Support Infinite and Indefinite Time Constructs.doc Disposition: Duplicate or Merged OMG Issue No: 16997 Title: forever is misdefined Source: Ed Barkmeyer, NIST, edbark@nist.gov Summary: In clause 9.4, 'forever' is defined as: "the time period that does not start on some time point and does not end on some time point". This is interpreted "there are two time points t1 and t2 such that the time period does not start on t1 and does not end on t2". What is intended is "the time period that starts on no time point and that ends on no time point". Further, this definition does not identify any time point sequence that makes the term 'time period' appropriate, and it eliminates all described ways to define a time point sequence. It seems that 'forever' should be classified 'time interval', with the above qualifications, not 'time period'. Or perhaps the intent is: "the time period that is the instance of each time point sequence that has no first time point and that has no last time point". Also, some Note should clarify the relationship of 'forever' to the Time Axis. Clause 8.1 does not say that the Time Axis is a time interval. Is 'forever' the time interval that is the "segment of the Time Axis" that covers all of it? Or is 'forever' the same thing as the Time Axis? I.e., is the Time Axis itself a time interval and 'forever' a synonym? Resolution: Resolved by issue 17540 and 16993. Revised Text: Disposition: Duplicate or Merged