W3C home > Mailing lists > Public > public-prov-wg@w3.org > October 2011

Re: Prov-o call on Monday 12:00noon US ET

From: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
Date: Mon, 24 Oct 2011 16:54:24 +0100
Message-ID: <4EA58A30.1040201@cs.man.ac.uk>
To: Daniel Garijo <dgarijo@delicias.dia.fi.upm.es>
CC: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>, Luc Moreau <L.Moreau@ecs.soton.ac.uk>, public-prov-wg@w3.org
On 24/10/2011 16:49, Daniel Garijo wrote:
> Yes, Khalid, but if you have the same entity used 2 times by different 
> process executions
> with the same role, you would also need 2 different EntityInRole.
Yes, if the same entity play two different roles w.r.t. the same process 
execution, then we need to create two different EntityInRoles.

> Imagine that pe1 uses e1Input1 (entity e1 with role: Input1) at time t1.
> According to our current modeling, we would assert t1 to the 
> entityInRole (with hasTemporalValue).
> If some time later we execute another p2 that uses e1 with the same 
> role at time t2, we cannot use e1Input1,
> because it has already associated t1. That is why we would need 
> e1Input1' (a new EntityInRole instance).
> But I remember we already discussed this with Satya :S
> It seems that we should make it clear somewhere, since people are 
> getting confused.
Yes, I agree. We need to write it down. It is probably not the most 
elegant solution, but it is a solution that works :-)


> Best,
> Daniel
> 2011/10/24 Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk 
> <mailto:Khalid.Belhajjame@cs.man.ac.uk>>
>     On 24/10/2011 15:44, Stian Soiland-Reyes wrote:
>         On Mon, Oct 24, 2011 at 12:07, Luc
>         Moreau<L.Moreau@ecs.soton.ac.uk
>         <mailto:L.Moreau@ecs.soton.ac.uk>>  wrote:
>             That's exactly the point, time is associated with
>             generation/use, not
>             entities.
>         But as we have not (as of yet) made a deliberate n-ary
>         relationship
>         Generation or Use class in PROV-O - so prov:wasGeneratedAt is
>         associated with an Entity (as it can only be generated once
>         within an
>         account) and prov:assumedRoleAt with an EntityInRole (as it
>         can only
>         be prov:wasASsumedBy one Entity).
>         To be fair this is not a direct mapping with PROV-DM, because
>         it would
>         allow the same entity-in-role to be prov:used by two different
>         PEs -
>         the prov:assumedRoleAt would only record time of the first
>         such use.
>         On the other hand a PE could actually be using the entity several
>         times, and we don't have a way to record each of these unless
>         we do it
>         as separate roles each time. (And still can't capture the
>         duration of
>         the use)
>     >From my understanding that is not the case. If the same entity is
>     used twice by two different process executions or by the same
>     process execution, then we will have to create two EntityInRole(s)
>     each associated with a different role.
>     For example consider an entity e that is used by a process
>     execution p such that the role of e w.r.t. p is  r, and let p' be
>     another process execution that uses e such that the role of e
>     w.r.t. p' is r'.
>     Using prov-o, we will have two entityinRoles that represent the
>     entity e but with different roles. Consider that these
>     entityinroles are er and er'. er and er' will have as properties
>     the characterizing attributes of e. Additionally, er (resp. er')
>     will have the role property r (resp. r').
>     Khalid
Received on Monday, 24 October 2011 15:54:59 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 16:51:03 UTC