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RE: [Minutes] 2016-02-03

From: <Simon.Cox@csiro.au>
Date: Sun, 20 Mar 2016 02:35:54 +0000
To: <frans.knibbe@geodan.nl>, <chris.little@metoffice.gov.uk>
CC: <allaves@fi.upm.es>, <public-sdw-wg@w3.org>
Message-ID: <2ed330831b75434e90365e848b156566@exch1-mel.nexus.csiro.au>
OWL Time is an implementation of Allen calculus, therefore focussed exactly on interval and event ordering. So AFAICT the ordering requirement is already dealt with. The requirements were written down as-is without any specific consideration of whether they were already accommodated by the prototype. That is as it should be, but I don’t think this requirement leads to any new work in the Time ontology related to ordering.

However, as Josh points out, the Time ontology does not include any predicates to link the time resources to objects/entities/features, or to web-resources. I guess we should consider whether these could be standardized at all.


From: Frans Knibbe [mailto:frans.knibbe@geodan.nl]
Sent: Saturday, 19 March 2016 12:31 AM
To: Little, Chris <chris.little@metoffice.gov.uk>; Cox, Simon (L&W, Clayton) <Simon.Cox@csiro.au>
Cc: Alejandro Llaves <allaves@fi.upm.es>; SDW WG Public List <public-sdw-wg@w3.org>
Subject: Re: [Minutes] 2016-02-03

Hello Chris, Simon,

Chris's comment on issue 15 seems important, that is why I would like to ask for Simon's thoughts before I change the UCR document. There is problem with expressing that "a web resource is in the past, present or future with respect to another web resource". But is the problem that it is currently not possible with OWL Time? Or is the problem that it is difficult to use because of sparse documentation, lack of examples and/or the spec being to abstract and mathematical? We could introduce a new requirement anyway, but the way it is phrased should depend on the answer of that question. And I would not want to insinuate that something is not possible with OWL Time while in fact it is.

As for issue 26, it seems the August 2020 example is inappropriate, since it can be expressed as xsd:gYearMonth. So I think we should not mention that example.


2016-03-02 18:08 GMT+01:00 Little, Chris <chris.little@metoffice.gov.uk<mailto:chris.little@metoffice.gov.uk>>:
Hello Frans,

I think your précis of the issues is spot-on.

Issue 26
I can only add to the last example that “August 2020” can be expressed in ISO8601, as the standard allows truncation from the right, but not the left (I.e 2020-08 is valid, but 12-25 for an unknown Christmas Day is not.) I am not sure about XSD without rummaging around.

For Issue 15, I would like to see some concrete examples as to how one would use the existing OWL Time to relate some resources, in whatever syntax is appropriate. At present, it is rather abstract and mathematical in my head.


From: Frans Knibbe [mailto:frans.knibbe@geodan.nl<mailto:frans.knibbe@geodan.nl>]
Sent: Thursday, February 18, 2016 11:04 AM
To: Little, Chris
Cc: Alejandro Llaves; SDW WG Public List
Subject: Re: [Minutes] 2016-02-03

Hello Chris,

Thank you for taking action. We should now look into if and how resolving the issues leads to changes to the UCR doc.

We are facing the following decisions:

On issue-15<https://www.w3.org/2015/spatial/track/issues/15>. A new requirement for the OWL Time deliverable will be added to the UCR document: "It should be possible to declare that a web resource is in the past, present or future with respect to another web resource".  Does this make sense in light of OWL Time already supporting this functionality (see the last messages in this e-mail thread<https://lists.w3.org/Archives/Public/public-sdw-wg/2015Aug/0003.html>)?

On issue-26<https://www.w3.org/2015/spatial/track/issues/26>. It seems we should keep the basic requirement as it is ("It should be possible to describe time points and intervals in a vague, imprecise manner."). A more extensive list of examples should be supplied to illustrate what we mean by that. Examples to list are:

  *   An event happend at the second quarter of the 9th century (the calendar used for this fact is unknown)
  *   Something occured in the afternoon of july 1st, 2011 (the time interval 'afternoon' is not precisely defined)
  *   A photo is known to be taken on a Christmas day, but the year is unknown.
  *   An event took place in the later part of the Jurassic (with 'later part' being imprecise, as opposed to 'Late Jurassic')
  *   Something is known to take place somewhere in August 2020 (only year and month are known, which is difficult to express in ISO-8601 or standard XSD datatypes)
Do you agree with the requirement and the examples?


2016-02-04 13:34 GMT+01:00 Little, Chris <chris.little@metoffice.gov.uk<mailto:chris.little@metoffice.gov.uk>>:
Dear Frans and Alejandro

I noticed that two issues against my name were still open:

Issue-15 Time req. not clear - represent past, present and future
Issue-26 Clarification of temporal vagueness

Last year, you kindly led us into some extended discussion and clarified the requirements into something more substantial.

I tried to summarise the outcomes in the tracker Notes (it took me a while to remember how to do things).

I have now put both Issues into Pending review. Do you, or anyone else, have any objection to closing them?

The only outstanding item from the threads was for me to add some terminology and definition to the Glossary, which I will do, as we agreed the terminology was diverse and potentially confusing.

Best wishes, Chris

Received on Sunday, 20 March 2016 02:36:45 UTC

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