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RE: (groan, not again): OGC Temporal DWG. Was: space and time

From: Little, Chris <chris.little@metoffice.gov.uk>
Date: Thu, 14 Aug 2014 09:00:52 +0000
To: Gannon Dick <gannon_dick@yahoo.com>, "andrea.perego@jrc.ec.europa.eu" <andrea.perego@jrc.ec.europa.eu>, "frans.knibbe@geodan.nl" <frans.knibbe@geodan.nl>, "Simon.Cox@csiro.au" <Simon.Cox@csiro.au>, "Chris Beer" <chris@codex.net.au>
CC: "public-locadd@w3.org" <public-locadd@w3.org>, "public-egov-ig@w3.org" <public-egov-ig@w3.org>, public-lod <public-lod@w3.org>, "temporal@lists.opengeospatial.org" <temporal@lists.opengeospatial.org>, Piero Campalani <cmppri@unife.it>, Matthias Müller <matthias_mueller@tu-dresden.de>
Message-ID: <3DAD8A5A545D7644A066C4F2E82072880EA5A7A8@EXXCMPD1DAG4.cmpd1.metoffice.gov.uk>
Hi Gannon,

Thank you for this. I think a lot of people have forgotten how much mathematics and science were engendered by trying to construct calendars and timescales, for whatever purposes, and I think you are helping carry that flag.

However, in the OGC context of trying to produce a first Best Practice and some straightforward recommendations for future work, we have already ruled calendars, especially weeks and months, other than ISO8601 Gregorian, out of scope. And sadly, I think we will rule out true solar time too, though people's need for conversion to and from local solar time is a well established, and has very important use cases, such as for aerial imagery shadow interpretation.

I think we should capture that particular use case and incorporate details of the conversion of UTC to and from local solar time, perhaps as an engineering report, but I think the resources are not available for our stated delivery in December 2014. 

Do you know of any authoritative sources that we could reference?

Best wishes, Chris

-----Original Message-----
From: Gannon Dick [mailto:gannon_dick@yahoo.com] 
Sent: Wednesday, August 13, 2014 6:38 PM
To: andrea.perego@jrc.ec.europa.eu; frans.knibbe@geodan.nl; Simon.Cox@csiro.au; Chris Beer; Little, Chris
Cc: public-locadd@w3.org; public-egov-ig@w3.org; public-lod; temporal@lists.opengeospatial.org; Piero Campalani; Matthias Müller
Subject: (groan, not again): OGC Temporal DWG. Was: space and time

Hi Chris,

FWIW.

While commerce depends upon Product Release Dates and Versioning, geographic information can default to the Julian Calendar harmonics.  Not having to deal with this administrative detail is a real, pardon the expression, time saver.  So, I did the math and made a spreadsheet (FODS or EXCEL), a prototype generic version "Release Clock". This calendar is not in harmony with astronomical calculations, which use the Winter Solstice as an anchor rather than New Year's.  I apologize for this shameless attempt to curry favour with Champagne Manufacturers ;-)

The calendar is by year, with anchors at New Year's and New Year+1.  There are three arc control points.  These are arbitrary but can be recognized holidays - and the key word is "recognized".  For example I used Easter ~ Passover ~ Jerusalem Tourist Season.  The control point labels (identity) has no Controlling Authority, that is, they have no effect on the graph (timeline).

http://www.rustprivacy.org/2014/balance/gts/utct.zip


Overseas Banks and Government Mint Printing Presses work over night.  Human Resources and a Retail Store's safe in the back room do not.  Neither do many Cultural Heritage resources.  Work-Life Balance gets, um, unbalanced.

--Gannon
--------------------------------------------
On Tue, 7/29/14, Gannon Dick <gannon_dick@yahoo.com> wrote:

 Subject: RE: OGC Temporal DWG. Was: space and time

 Date: Tuesday, July 29, 2014, 12:45 PM
 
 
 
 On Tue, 7/29/14, Little, Chris <chris.little@metoffice.gov.uk>
 wrote:
  
  And I agree that
 transparency about calendar algorithms is an issue, not  just
  in their book. This isone thing that I  hope that an OGC Best Practice document could help, in  however a small way.
  
 
 ============
 
 Hi Chris,
 
 Maybe it is time to "go
 big" - Universal Coordinated Calendar Time (UTCT).  In  the near term, (this Julian Century) the Calendar has no  unidentified shifts.  We know about Leap Days and the  Calendar is ignorant of Leap Seconds.  So, it is  possible.  
 
 This presents
 a problem for Linked Data because even though Personal  Identity is coupled to Occupation and Occupation is coupled  to the Location of the Workplace, these are couplings not  correlations.
 
 Mid-day,
 Noon, is a mean value, but one can't assume regression  to the mean. At the Equator the "Authority" -  Solar Noon - has a whopping 7 1/2 minute time shift.  This  is not hidden, but it is overwhelmed by the Equation of  Time.  The shifts, on a day-to-day basis do not accumulate  to significance on a year-to-year basis. To determine  coupling constants is a fools errand.
 
 e.g. http://www.rustprivacy.org/2014/balance/utct.jpg

 
 When people triangulate in
 their heads they use 3,4,5 triangles to keep the math  easy.  For this reason, the Axis length is 500%.  All  "shifts" (events which impact Work Life Balance)  are vertical. Sorry, the "Day" indicator can't  update automatically - it's a PDF.
 
 WDYT?
 
 Best,
 
 --Gannon (J.) Dick ;-) I'm
 not a commuter, I have a funny name.
 
 
  
 
 -----Original Message-----
  From: Gannon
 Dick [mailto:gannon_dick@yahoo.com]
  
  Sent: Thursday, July 24,
 2014 5:24 PM
  To: andrea.perego@jrc.ec.europa.eu;
  frans.knibbe@geodan.nl;
  Simon.Cox@csiro.au;
  Chris Beer; Little, Chris
  Cc:
 public-locadd@w3.org;
  public-egov-ig@w3.org;
  public-lod; temporal@lists.opengeospatial.org;
  Piero Campalani; Matthias Müller
  Subject:
  Re: OGC Temporal
 DWG. Was: space and time
  
 
 Hi Chris,
  
  who wrote:
  One concern that I
  have is
 that we do not re-invent the  wheel, and do
  nugatory work, hence this email. I do not  envisage that we
  will need to do much with
 Calendars, which  have been
  covered so
 well by Dershowitz and Reingold.
  
  =====================================
  No question the quality of the issue
 coverage
  (Calendars) is first rate.
  
  However, the computations
 are not transparently
  self-evident and the
 references you cite in the Wiki are not
 
 available on-line - or are they ?
  
  3. Calendrical Tabulations 1900-2200, Edward  M.
  Reingold, Nachum Dershowitz. Hardcover:
 636 pages.
  Publisher: Cambridge University
 Press (16 Sep 2002)
  Language: English
 ISBN-10: 0521782538 ISBN-13:
 
 978-0521782531
  
  4.
  Calendrical Calculations, Nachum Dershowitz,  Edward M.
  Reingold. Paperback: 512 pages.
 Publisher: Cambridge
  University Press; 3
 edition (10 Dec 2007) Language: English
 
 ISBN-10: 0521702380 ISBN-13: 978-0521702386 
  
  Accessability to
 "Wheels
  known to have been
 invented" is a Wiki issue, I
  think.
  
  --Gannon
 
 
  
  
  
 
 --------------------------------------------
  On Thu, 7/24/14, Little, Chris <chris.little@metoffice.gov.uk>
  wrote:
  
  
 Subject: OGC
  Temporal DWG. Was: space and
 time
   To:
  "Gannon
 Dick" <gannon_dick@yahoo.com>,
  "andrea.perego@jrc.ec.europa.eu"
  <andrea.perego@jrc.ec.europa.eu>,
  "frans.knibbe@geodan.nl"
  <frans.knibbe@geodan.nl>,
  "Simon.Cox@csiro.au"
  <Simon.Cox@csiro.au>,
  "Chris Beer" <chris@codex.net.au>
   Cc: "public-locadd@w3.org"
  <public-locadd@w3.org>,
  "public-egov-ig@w3.org"
  <public-egov-ig@w3.org>,
  "public-lod" <public-lod@w3.org>,
  "temporal@lists.opengeospatial.org"
  <temporal@lists.opengeospatial.org>,
  "Piero Campalani" <cmppri@unife.it>,
  "Matthias Müller" <matthias_mueller@tu-dresden.de>
   Date: Thursday, July 24, 2014, 9:36 AM
   
   #yiv4303497829
   #yiv4303497829 --
 .yiv4303497829EmailQuote
  
 
 {margin-left:1pt;padding-left:4pt;border-left:#800000 2px
   solid;}#yiv4303497829 
  
 
   Dear Colleagues,
  
  
   OGC started a Temporal Domain Working  Group
  last year  to address a number of
 problems in the
  geospatial domain. In
 particular, that time is usually
  just
 viewed as Yet Another  Attribute of Features, rather
  than a first class  coordinate.
    
   We agreed earlier this
 year, in Geneva, that
  the OGC  Naming
 Authority would have a branch to register
 
 Temporal,  and index based, Coordinate Reference  Systems,
  and we agreed  on the fundamental
 attributes that a CRS
  should have to be
 registered. 
    
   We
 hope to produce a Best Practice document
 
 this year  to help clarify many confusions between CRSs,
  notations,  calendars, operations and
 calculations. I think
  that now we  have a
 good enough understanding of the
 
 underlying  conceptual issues and current  geospatial
  standards.
    
   We have been
  accumulating
 info on an open wiki http://external.opengeospatial.org/twiki_public/TemporalDWG/WebHome

   and discussing via our
  
  mailing list, though we are not very
 disciplined about
  it.
  
  
   One concern that I
 
 have is that we do not re-invent the  wheel, and do
  nugatory work, hence this email. I do not  envisage that we
  will need to do much with
 Calendars, which  have been
  covered so
 well by Dershowitz and Reingold.
  
   
   Best wishes, Chris
  
   
    
   Chris Little
   
   
   Co-Chair,
  OGC Meteorology & Oceanography Domain
 Working  Group
  Co-Chair, OGC Temporal
 Domain  Working Group
   
   
   
   IT
 Fellow -
   Operational
 
 Infrastructures
   
   
   Met Office  FitzRoy Road  Exeter
 Devon
  EX1 3PB  United Kingdom
   
  
  
   Tel: +44(0)1392 886278  Fax: +44(0)1392
  885681  Mobile:
   +44(0)7753
 880514
   
   
   E-mail: chris.little@metoffice.gov.uk
  http://www.metoffice.gov.uk

    
   I am normally at
 work
  Tuesday,
   Wednesday
 and Thursday each
  week
  
  
    
    
    
    
  
  
    
    
   
   
 
Received on Thursday, 14 August 2014 09:01:29 UTC

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