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Re: PROV-ISSUE-280 (TLebo): {started,ended,used,wasGenerated}At <-> prov:qualified [ prov:atTime ] pattern [Ontology]

From: Timothy Lebo <lebot@rpi.edu>
Date: Sun, 4 Mar 2012 13:07:30 -0500
Cc: Provenance Working Group <public-prov-wg@w3.org>
Message-Id: <0672187C-AC0A-4525-94B8-70D21DBBCF25@rpi.edu>
To: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Luc,

The intent for this issue is to uniformly apply the unqualified / qualified patterns that has had some success in prov-o.
I remember this example being discussed at F2F, and am working from that impetus.

To answer your question about different times, the property can assume multiple values for the same subject:

:input_1 prov:usedAt "2012-03-03T21:04:54-05:00", 
                                      "2012-03-04T10:58:04-05:00" .

But I now realize that the property should be reversed to suit our standing goals [1], specifically "directionality of the triple should point to the Element that "existed earlier""

:dataSet
   prov:usedEntityAt  "2012-03-03T21:04:54-05:00", "2012-04-04T21:04:54-05:00";
   prov:used :input_1, :input_2;
   prov:qualified [
      a prov:Usage;
      prov:entity :input_1;
      prov:atTime "2012-03-03T21:04:54-05:00";
   ], [
      a prov:Usage;
      prov:entity :input_2;
      prov:atTime "2012-04-04T21:04:54-05:00"
   ];
.


The largest motivation for applying the unqualified / qualified pattern to time is to avoid a level of indirection for Activity start and end times.
Requiring the TimeInstant indirection is going to cause nontrivial practical issues with respect to query times and duplicate results.

I've started eg-14 [2] so that we can stay concrete in this ISSUE.

Regards,
Tim



[1] http://www.w3.org/2011/prov/wiki/ProvRDF#Mapping_goals
[2] http://dvcs.w3.org/hg/prov/file/a7e1c279eb6c/examples/eg-14-unqualified-and-qualified-times/rdf/eg-14-unqualified-and-qualified-times.ttl


On Mar 4, 2012, at 5:14 AM, Luc Moreau wrote:

> Hi Tim,
> 
> Can you handle two usages at different times for a same entity? I fear that a property usedAt does not allow for this.
> 
> Professor Luc Moreau
> Electronics and Computer Science
> University of Southampton 
> Southampton SO17 1BJ
> United Kingdom
> 
> On 4 Mar 2012, at 02:09, "Timothy Lebo" <lebot@rpi.edu> wrote:
> 
>> Sorry, the page cut me short:
>> 
>> Time can be incrementally qualified, just like the binary relations.
>> 
>> The following pattern could be used for started, ended, used, and wasGeneratedAt:
>> 
>> 
>> :input_1 prov:usedAt "2012-03-03T21:04:54-05:00" .
>> :input_2 prov:usedAt "2012-04-04T21:04:54-05:00" .
>> 
>> :dataSet
>>  prov:used :input_1, :input_2;
>>  prov:qualified [
>>     a prov:Usage;
>>     prov:entity :input_1;
>>     prov:atTime "2012-03-03T21:04:54-05:00";
>>  ], [
>>     a prov:Usage;
>>     prov:entity :input_2;
>>     prov:atTime "2012-04-04T21:04:54-05:00"
>>  ];
>> .
>> 
>> 
>> 
>> 
>> http://www.w3.org/mid/E1RtEkN-0003xz-Ik@tibor.w3.org
>> 
>> http://www.w3.org/mid/CAKc1nHfd8B1a9m=eKCACQJpNZgGR1GJdaiDpNpnTxqycb4LDUA@mail.gmail.com
>> 
>> 
>> 
>> 
>> -Tim
>> 
>> On Mar 3, 2012, at 9:05 PM, Provenance Working Group Issue Tracker wrote:
>> 
>>> PROV-ISSUE-280 (TLebo): {started,ended,used,wasGenerated}At <-> prov:qualified [ prov:atTime ] pattern [Ontology]
>>> 
>>> http://www.w3.org/2011/prov/track/issues/280
>>> 
>>> Raised by: Timothy Lebo
>>> On product: Ontology
>>> 
>>> Time can be incrementally qualified, just like the binary relations.
>>> 
>>> 
>>> :dataSet
>>> prov:used :input_1, :input_2;
>>> prov:usedAt "2012-03-03T21:04:54-05:00", "2012-04-04T21:04:54-05:00";
>>> prov:qualified [
>>>    a prov:Usage;
>>> 
>>> 
>>> 
>>> 
>>> http://www.w3.org/mid/E1RtEkN-0003xz-Ik@tibor.w3.org
>>> 
>>> http://www.w3.org/mid/CAKc1nHfd8B1a9m=eKCACQJpNZgGR1GJdaiDpNpnTxqycb4LDUA@mail.gmail.com
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>> 
>> 
> 
Received on Sunday, 4 March 2012 18:08:24 GMT

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