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Agenda for SDWWG teleconference 17 February 2016 20:00 GMT

  • Chair: Ed
  • Scribe: TBA
  • Regrets:
This meeting: Clemens,Andreas, Lewis, Lars


  1. Check bots are running (see below)
  2. Matching everyone on IRC and Webex: Each person should type 'present+ ' followed by their name.
  3. Appoint Scribe. Scribe should enter 'regrets+ ' followed by the names of people who have sent regrets (ideally by adding their own name to this page)
  4. Approving last meeting's minutes
  5. Patent Call

Main agenda

  1. Short update on last weeks Face to Face
  2. Coordination with DWBP See homework
  3. Temporal Issues [as added by Chris Little, following F2F3]
  • Accuracy versus Precision confusion is made worse by the only widely accepted temporal notation (ISO8601) which often conveys unjustified precision. E.g. A document update time of 2016-02-16T00:00:00Z is highly unlikely to imply that the document was updated at precisely midnight UTC.
  • Numerous software artifacts conflate times and dates, and sometimes mistakenly assume dateTime objects can be used as a coordinate reference system.
  • The current ISO8601:2004 standard states that the notation is meant to reflect an underlying Gregorian calendar, with leap seconds. Many occurrences of apparent ISO8601 timestamps ignore leap seconds and the tens of seconds difference between legal civil time and GPS time. Many people refer to the oboslete ISO8601:1988 as it is publicly available, whereas the current version has to be bought.
  • There is an assumption that in this age, computer times, such as from a system log with IETF RFC 3339 timestamps, are comparable with sub-second precision. Even when NNTP protocols have been correctly implemented, this is difficult to achieve.
  • Some countries only switched to the Gregorian calendar as late as the 1920s, so historical documents from between 1588 and 1923 may be several days adrift, depending on the country, giving inaccuracy in data extraction.
  • There are many other calendar systems in use, and there is no agreed notation as to which is used, never mind agreed and accurate algorithms for their implementation. There is a rough categorisation of calendars into those that can be related directly to the Gregorian, because they are algorithmically based, and those that are fundamentally observation based, with a precision of minutes or even days.
  • Overlying temporal ontologies may not allow valid reasoning if the underlying temporal 'microformats' are not accurate at the appropriate level.
  • There is now an OGC Standards Working Group to produce standardised WKT (Well Known Text) to specify non-Gregorian calendars (e.g. no leap seconds, or no leap days, or 360 days/year, etc).
  • There is a SDW WG proposal to minimally enhance the OWL Time vocabulary with non-Gregorian calendars.

Dial in details

  Joining instructions: (official participants and invited guests only)
  Meeting time is 20:00 GMT throughout northern hemisphere winter/southern summer
  For audio: WebEx
  For text discussions, minutes, joining the speaker queue, actions & issues IRC channel: #sdw on irc.w3.org on port 6667
  Please be sure to join both IRC and WebEx and use the same nick in both (or it gets very confusing)
  When you join the IRC channel, please immediately type 'present+ {yourname}' (this adds your name to the participants list in the minutes)
  If you dial in by phone you'll need this:
  Meeting number: 648 567 445 
  Audio connection: +1-617-324-0000 (US Toll Number )
  See WebEx Best Practices for more
  W3C Telecon Resources:
  Zakim instructions in English
  Basic instructions in Portuguese

To start the meeting, check that trackbot is in the IRC channel (it usually is). If not, type:

/invite trackbot

Then you can type:

trackbot, start meeting

That should invite zakim and RRSAgent and generally get things ready to go. As a reminder: the Zakim IRC bot handles things like the speaker queue, RRSAgent handles the minute-taking, present and regrets list etc.

Please note that you will see a message that Zakim does not see any meetings scheduled at this time. This is a reference to the old conference bridge (also called Zakim) that is no longer in use. Scheduling is now done under the WebEx system. If you're feeling nostalgic for the old Zakim greeting, it's archived (of course).

Once you have started the meeting, you should see all three bots running:

If any are not in the room, type /invite and then the name of the bot

During the meeting you may need to set the access permissions on the chat log with this command:

RRSAgent, make logs public

Then to create the minutes, type RRSAgent, draft minutes


Minuteshttp://www.w3.org/2016/02/17-sdw-minutes +
ScribeKerry +
SubjectDWBP Coordination +
TypeTelecon +
"Date" is a type and predefined property provided by Semantic MediaWiki to represent date values.
February 17, 2016 +