- From: Paolo Missier <Paolo.Missier@ncl.ac.uk>
- Date: Tue, 07 Feb 2012 13:51:24 +0000
- To: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
- CC: Provenance Working Group <public-prov-wg@w3.org>
Stian, all inline. On 2/7/12 1:09 AM, Stian Soiland-Reyes wrote: >> Is the following valid? >> >> wasGeneratedBy(e,,2001-10-26T21:32:52) >> wasGeneratedBy(e,,2011-11-27T21:23:34) > You can't write time like that in ASN, they must be quoted literals or > kind-a-CURIEs. (And we should choose one of those to use for time in > ASN - it seems we already like to talk about t1,t2 etc, but elsewhere > claim it is XSD Date time. Given discussions in F2F I would suggest > the former.) > > > My interpretation of this is that 2011-11-27T21:23:34 and > 2001-10-26T21:32:52 is the same event (the generation event). I don't > know what that means, perhaps that the generation is a very slow > thing, that the observer's clock has moved but the entity's clock has > not (say a frozen computer simulation), that the two times are the > same, or that the asserter is plain simply wrong. > > And so I don't think we should say much about it. > > It becomes of course much easier to narrow down the possibilities if > we separate times and events, as currently done in PROV-O with using > the (no longer time:) Instant resources - here you would just say: > > > :e prov:wasGeneratedAt :t1 . > :e prov:wasGeneratedAt :t2 . > > :t1 prov:inXSDDateTime "2001-10-26T21:32:52"^^xsd:dateTime . > :t2 prov:inXSDDateTime "2011-11-27T21:23:34"^^xsd:dateTime . > > (or equivalent long-version with prov:Generation and prov:hadTemporalValue) > > prov:wasGeneratedAt is functional, because there is only one > generation event of an entity. Thus we know that :t1 == :t2 and can > limit our trouble-search there - in this case we could get an OWL > error because prov:inXSDDateTime is a functional datatype, or not, > depending on how strongly we choose to believe the owl:sameAs. > > > -- ----------- ~oo~ -------------- Paolo Missier - Paolo.Missier@newcastle.ac.uk, pmissier@acm.org School of Computing Science, Newcastle University, UK http://www.cs.ncl.ac.uk/people/Paolo.Missier
Received on Tuesday, 7 February 2012 13:53:45 UTC