W3C home > Mailing lists > Public > public-prov-wg@w3.org > September 2012

Re: PROV-ISSUE-447: subactivity relation [prov-dm]

From: Luc Moreau <l.moreau@ecs.soton.ac.uk>
Date: Tue, 04 Sep 2012 17:31:15 +0100
Message-ID: <EMEW3|1daf093dfc19e496620dc0785e1ec14do83HVI08l.moreau|ecs.soton.ac.uk|50462CD3.9090100@ecs.soton.ac.uk>
To: Khalid Belhajjame <Khalid.Belhajjame@cs.man.ac.uk>
CC: public-prov-wg@w3.org
Hi Khalid,

I am opposed to introduce wasSubactivityOf without studying 
constraints/inferences/etc...

I don't think this example makes much sense:

activity(a1,2011-11-16T00:00:00,2011-11-17T00:00:00) // in 2011
activity(a2,2012-11-16T00:00:00,2012-11-17T00:00:00)  // in 2012
wasSubactivity(a1,a2)

As indicated previously, it's a whole complete new design that
we have to undertake, for which we don't have enough experience.

Cheers,
Luc


On 04/09/12 17:23, Khalid Belhajjame wrote:
> I would go for option 1 provided that we dont say anything from the
> point of view of ordering sub activities, with  respect to the parent
> activity. If the only requirement is to have a means to know that one
> activity is a child activity of another then I dont see a problem in
> introducing the relation sub-activity. We did some thing similar with
> collections to a certain degree, when we choose to keep in the DM the
> membership relation, so why not do the same for activities.
>
> Thanks, khalid
>
> On 4 September 2012 14:57, Luc Moreau <l.moreau@ecs.soton.ac.uk> wrote:
>>
>> Dear all,
>>
>> I would like to kickstart discussion on this public comment.
>> This has already been asked on several occasions, and this has previously
>> been raised on the mailing list.
>>
>> I essentially see two options:
>> 1. We change the model and add a sub-activity relation.
>> 2. We don't change the model, but we come with a good justification for not
>>      changing it.  In particular, we previously said this was out of scope.
>> Perhaps,
>>      we could point to some vocabularies already doing this.
>>
>> What are your views?
>> Regards,
>> Luc
>>
>>
>> On 06/07/12 18:12, Provenance Working Group Issue Tracker wrote:
>>> PROV-ISSUE-447: subactivity relation [prov-dm]
>>>
>>> http://www.w3.org/2011/prov/track/issues/447
>>>
>>> Raised by: Timothy Lebo
>>> On product: prov-dm
>>>
>>> There is a thread discussing the issue raised by Sutra at
>>> http://www.w3.org/mid/CAJCyKRqtC47OWc_rDRhFcQGdJ-yy2toQBCguUywFGZpHO5Q8Jw@mail.gmail.com
>>>
>>> The original email:
>>>
>>> On Fri, Jul 6, 2012 at 2:45 PM, Satrajit Ghosh <satra@mit.edu> wrote:
>>> hello,
>>>
>>> i was discussing this with luc and based on his feedback thought it might
>>> be
>>> useful to bring this up on the list.
>>>
>>> ----
>>> question:
>>> how do you encode that a certain activity "emailing a letter" happened
>>> during another activity "a meeting"?
>>>
>>> for example we conduct research studies/projects.
>>>
>>> activity(p1, [prov:type='ex:Project'])
>>> activity(p2, [prov:type='ex:MRIScanning', ex:session=1])
>>> activity(p3, [prov:type='ex:MRIScanning', ex:session=2])
>>>
>>> how would i encode that this activity p2 and p3 were conducted during p1?
>>> how would i encode p3 followed p2?
>>>
>>>
>>> luc's response:
>>> Regarding your question, there may be a few options:
>>> you could add time information to your activities. This will help you
>>> understand their ordering.
>>>
>>> Alternatively, if you want an explicit dependency in your graph, then p2
>>> may
>>> generate something
>>> that starts p3, and/or is consumed by p3
>>>
>>> Finally, prov doesn't have relations between activities, to express their
>>> nesting, etc. It's important
>>> but we felt this is not specific to provenance, but to process executions.
>>> ----
>>>
>>> it's the last point on this response that i was not completely sure about.
>>> why "relations between activities" is "not specific to provenance, but to
>>> process executions."
>>>
>>> in the above example, one could say:
>>>
>>> wasSubtaskOf(p2, p1)
>>> wasSubtaskOf(p3, p1)
>>> wasFollowedBy(p2, p3)
>>>
>>> any clarification as to why such relations would be outside the realm of
>>> provenance would be much appreciated.
>>>
>>> cheers,
>>>
>>> satra
>>>
>>>
>>>
>> --
>> Professor Luc Moreau
>> Electronics and Computer Science   tel:   +44 23 8059 4487
>> University of Southampton          fax:   +44 23 8059 2865
>> Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
>> United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
>>
>>

-- 
Professor Luc Moreau
Electronics and Computer Science   tel:   +44 23 8059 4487
University of Southampton          fax:   +44 23 8059 2865
Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
Received on Tuesday, 4 September 2012 16:31:52 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 4 September 2012 16:31:53 GMT