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Re: Update on PROV-O OWL file (Action item 55)

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Thu, 16 Feb 2012 22:04:48 +0000
Message-ID: <EMEW3|cdfb056b4f3d40e42b4eb9fe62386eaeo1FM4s08L.Moreau|ecs.soton.ac.uk|4F3D7D80.5040708@ecs.soton.ac.uk>
To: Satya Sahoo <satya.sahoo@case.edu>
CC: public-prov-wg@w3.org
Hi Satya

On 16/02/12 21:36, Satya Sahoo wrote:
> Hi Luc,
>
>
>     It's incorrect, WD3 does not associate time with Entity.
>
> Section 2.1.2.1, DM-TPWD:
> "An entity generation event is the instantaneous event 
> <http://www.w3.org/TR/2012/WD-prov-dm-20120202/#dfn-event> that marks 
> the final instant of an entity's creation timespan, after which it 
> becomes available for use.

Indeed, time is associated with generation not entity.

> An entity usage event is the instantaneous event 
> <http://www.w3.org/TR/2012/WD-prov-dm-20120202/#dfn-event> that marks 
> the first instant of an entity's consumption timespan by an activity."
>
> Section 2.1.2.2, DM-TPWD:
>

Indeed, time is associated with usage not entity.
>
> "This specification only assumes that each instantaneous event 
> <http://www.w3.org/TR/2012/WD-prov-dm-20120202/#dfn-event> can be 
> mapped to an instant in some form of timeline."
>
> Section 5.3.1, DM-TPWD:
>

Yes, mapping of event to time, not entity to time.

> "The following generation assertions
>
>    wasGeneratedBy(e1,a1, 2001-10-26T21:32:52, [ex:port="p1", ex:order=1])
>    wasGeneratedBy(e2,a1, 2001-10-26T10:00:00, [ex:port="p1", ex:order=2])
>    
>
> state the existence of two events 
> <http://www.w3.org/TR/2012/WD-prov-dm-20120202/#dfn-event> in the 
> world (with respective times 2001-10-26T21:32:52 and 
> 2001-10-26T10:00:00), at which new entities, represented by entity 
> records identified by e1 and e2, are created by an activity, itself 
> represented by an activity record identified by a1."
>

Again, time associated with events.
>
> Section 5.3.1.2, DM-TPWD:
>
> "The following usage records
>
>    used(a1,e1,2011-11-16T16:00:00,[ex:parameter="p1"])
>    used(a1,e2,2011-11-16T16:00:01,[ex:parameter="p2"])
>    
>
> state that the activity, represented by the activity record identified 
> by a1, consumed two entities, represented by entity records identified 
> by e1 and e2, at times 2011-11-16T16:00:00 and 2011-11-16T16:00:01, 
> respectively;"
>

... again, time is with usage.
>
> Section 7.1, DM-TPWD:
>
> "wasStartedByAgent-ordering, wasAssociatedWith-ordering" constraints.
>
> Taken together, all the above statements describe association of 
> Entity (or its subclass Agent) with "event", which is in turn mapped 
> to Time - in effect, associating Entity with Time (each domain 
> application is free to decide "what" time).
>

What the above says is that time is a property of event. Not more.

> Also, I believe the DM supports representation of a simple provenance 
> assertion such as, "The MonaLisa portrait is dated to circa 15031519" 
> (MonaLisa portrait is an Entity).
>

How would you do it? I don't know.

> On a related note, I guess we need to resolve an outstanding issue of 
> whether to have a class for Event or Time, but the issue of Entity and 
> Activity both being associated with Event/Time is clear. Hence, Ivan's 
> original comment is still unresolved.
>
> Thanks.
>
> Best,
>
> Satya
>

Luc

>
>     On 16/02/12 20:45, Satya Sahoo wrote:
>
>         But as Luc replied the PROV-DM TPWD associated time
>         information with both Entity and Activity,
>
>
>     Luc
>
>
Received on Thursday, 16 February 2012 22:05:28 GMT

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