Re: EIIF draft needs unified person, rigorous when/where, criteria towards common ontology, use of phases

The serious error in ISO 8601 is that "without any further additions, a date and time as written above is
assumed to be in some local time zone." - http://www.cl.cam.ac.uk/~mgk25/iso-time.html

"Some local" is nowhere near acceptable for the purposes we are talking about.  Especially not as relief efforts begin to span global communications networks.   With the "Z" suffix that specifies that the time is in UTC it's fine for points in time - only.  But ISO 8601  has nothing to say about how to specify spans of time / intervals, floating durations, etc.

An ontology standard like OWL-time doesn't have to say, and shouldn't say ,anything about the implementation (text string or bits used).  It only specifies the structural relationships between the types, which it does well enough, and it also takes extreme care to explain that the semantics of a time necessarily include and always imply a single zone.

ISO 8601 apparently allows one to express the non-existent concept of a date/time without being fixed in any one time zone.  This is a plain semantic error, to allow the expression of something that seems to exist but in fact is ambiguous.

Craig Hubley




----- Original Message ----
From: Renato Iannella <renato@nicta.com.au>
To: public-xg-eiif <public-xg-eiif@w3.org>
Sent: Tuesday, November 25, 2008 7:41:33 PM
Subject: Re: EIIF draft needs unified person, rigorous when/where, criteria towards common ontology, use of phases



On 25 Nov 2008, at 09:45, Carl Reed wrote:

> Do you know if this document was considered (or not?). If not, why.


From the OWL-Time document:

"We can see from this example that it’s much more concise to use the XML Schema datatype dateTime. However, the advantage of using DateTimeDescription is that it can express more information than dateTime, such as "week", "day of week" and "day of year", so in the above example, we can also know that 01/01/2006 is Sunday, on the first day of the year, and in the first week of the year. "

Like you (and many others), I prefer ISO-8601

Cheers...  Renato Iannella
NICTA

Received on Wednesday, 26 November 2008 00:19:40 UTC