ontolog-forum
[Top] [All Lists]

Re: [ontolog-forum] Time representation

To: "[ontolog-forum] " <ontolog-forum@xxxxxxxxxxxxxxxx>
Cc: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Pat Hayes <phayes@xxxxxxx>
Date: Tue, 22 Jan 2008 22:47:06 -0600
Message-id: <p06230901c3bc77288e14@[192.168.1.2]>
At 9:12 PM -0500 1/22/08, creed@xxxxxxxxxxxxxxxxxx wrote:
>If the forum is going to begin discussing how to express time and the
>semantics of time, I would seriously suggest the group look at the various
>ISO standards and related IETF standards that dal with expressing time. If
>you are interested in expressing time intervals etc, I would suggest you
>look at the OGC Observations and Measurements standard.    (01)

Are these available on-line? Pointers?    (02)

Pat    (03)

>Any questions, please let me know.
>
>Regards
>
>Carl Reed
>OGC
>
>>  Dear John,
>>
>>  I'm glad you brought it up, because it was on my mind too:
>>
>>>  Re PTim: I realize that calling an interval a point is problematical.
>>>  But in anything that has to do with the physical world, there is no
>>>  way to specify a true point.  Perhaps a better term would be "grain
>>>  in time", abbreviated "Grit".
>>
>>  I think one of the constant challenges of ontology is to differentiate
>>  between common practice ways of representing things, e.g.
>>
>>>  There are so many hard problems, it's hard to say which are harder.
>>>  But the idea of taking the least significant digit as the criterion
>>>  for implicit granularity is fairly common for experimental data
>>>  (unless some explicit margin of error is stated).
>>
>>  And what they really are, i.e. in this case an interval or period. Now
>>  there is, in my mind, nothing wrong with naming an interval 14th Jan
>>  2008, but it needs to be understood that it has a start time of midnight
>>  at the start of the day, and an end time of midnight at the end of the
>>  day, and that it is not in any sense a point in time.
>>
>>  All this for me is independent of whether time is ultimately granular
>>  or continuous. Ultimately this only means at what point we can not longer
>>  tell whether one event happened before another.
>>
>>
>>  Regards
>>
>>  Matthew West
>>  Reference Data Architecture and Standards Manager
>>  Shell International Petroleum Company Limited
>>  Registered in England and Wales
>>  Registered number: 621148
>>  Registered office: Shell Centre, London SE1 7NA, United Kingdom
>>
>>  Tel: +44 20 7934 4490 Mobile: +44 7796 336538
>>  Email: matthew.west@xxxxxxxxx
>>  http://www.shell.com
>>  http://www.matthew-west.org.uk/
>>
>>
>>>  -----Original Message-----
>>>  From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx
>>>  [mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx]On Behalf Of
>>>  John F. Sowa
>>>  Sent: 21 January 2008 17:48
>>>  To: [ontolog-forum]
>>>  Subject: Re: [ontolog-forum] Time representation
>>>
>>>
>>>  Pat,
>>>
>>>  The position I most strongly advocate is not a specific ontology,
>>>  but a framework of conventions for organizing a multiplicity
>>>  of special cases (not necessarily consistent with one another),
>>>  making the implicit relationships explicit, and providing tools
>>>  and guidelines for mixing and matching.  The lattice of theories
>>>  is an example.  Robert Kent's IFF is a much more ambitious example.
>>>
>>>  I would recommend a fairly simple framework for starters, since
>>>  there's a danger of freezing half-baked ideas before they're fully
>>>  baked.  (RDF, for example, was hardly out of the oven before
>>>  Tim Bray tried, unsuccessfully, to pull it back in.)
>>>
>>>   > Do you have any granularity axioms?  That is one of the hardest
>>>   > ontological problems, in my experience.
>>>
>>>  There are so many hard problems, it's hard to say which are harder.
>>>  But the idea of taking the least significant digit as the criterion
>>>  for implicit granularity is fairly common for experimental data
>>>  (unless some explicit margin of error is stated).
>>>
>>>  Re PTim: I realize that calling an interval a point is problematical.
>>>  But in anything that has to do with the physical world, there is no
>>>  way to specify a true point.  Perhaps a better term would be "grain
>>>  in time", abbreviated "Grit".
>>>
>>>  John
>>>
>>>  PS re HTML email formats:  Your note of 11:18 was in a readable font
>  >> for Thunderbird, but your note of 11:37 appeared in a tiny, tiny font.
>>>  I had to increase the font size by two steps to make it the same as
>>>  the previous note.  But then the fonts for all other notes were too
>>>  big, and I had to decrease the default by two steps.
>>>
>>>  At least each of your notes was entirely in one font size.  I've
>>>  received some email in which each paragraph was in a progressively
>>>  smaller font.  That's why I hate HTML email.
>>>
>>>
>>>  _________________________________________________________________
>>>  Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
>>>  Subscribe/Config:
>>  http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
>>  Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
>>  Shared Files: http://ontolog.cim3.net/file/
>>  Community Wiki: http://ontolog.cim3.net/wiki/
>>  To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>>
>>
>>
>>
>>  _________________________________________________________________
>>  Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
>>  Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
>>  Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
>>  Shared Files: http://ontolog.cim3.net/file/
>>  Community Wiki: http://ontolog.cim3.net/wiki/
>>  To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>>
>>
>
>
>
>_________________________________________________________________
>Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/ 
>Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/ 
>Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
>Shared Files: http://ontolog.cim3.net/file/
>Community Wiki: http://ontolog.cim3.net/wiki/
>To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>    (04)


-- 
---------------------------------------------------------------------
IHMC            (850)434 8903 or (650)494 3973   home
40 South Alcaniz St.    (850)202 4416   office
Pensacola                       (850)202 4440   fax
FL 32502                        (850)291 0667    cell
phayesAT-SIGNihmc.us       http://www.ihmc.us/users/phayes    (05)


_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (06)

<Prev in Thread] Current Thread [Next in Thread>