Re: call for comments on publishing task models spec

Dear all,

  As we are not managing to attend the call, we would like to raise some questions via email.

  - How can we express with operators simple and multiple choices? Basically, is it possible to distinguish them?
  - There are additional task types that should be also integrated. For instance, the ones mentioned at: http://www.uclouvain.be/cps/ucl/doc/iag/documents/WP_8_Gonzalez.pdf
  - An 'alias' or 'synonym' could be added to the current task names, helping to trace equivalencies.

 I tried to send these concerns in a previous email, although the message status says it was processed and approved, it was not received... maybe because of the attached paper...

Best regards,
Vivian.


On 19 Jul 2012, at 00:35, Paolo Bottoni wrote:

> Hi everybody.
> 
> Thanks Dave and the CTT group for putting this together.
> 
> Here are my comments.
> 
> Concerning operators.
> 
> Interleaving (T1 ||| T2 ||| … TN): The connected tasks can be
> performed concurrently, without any specific constraint.
> Order independence (T1|=|T2 |=| … TN): the tasks can be performed in any order;
> Synchronisation (T1|[]|T2 |[]| … TN): The tasks are synchronised each other;
> Parallelism (T1||T2 || … TN): The tasks are performed in true paralllelism.
> 
> I think that the semantics should be a bit more precise, with respect
> to Task decomposition.
> 
> As I would intend it, from the names
> 
> Interleaving would meanthat any subtask of any task can be performed
> at any step,
> Order independence would mean that any task can be started when no
> other task is running, but no other task can be started once one has
> started until that one is finished
> Synchronisation would mean that each task must advance one step at the
> same time. This opens the problem whether all tasks must execute the
> same number of subtasks or some can end before the others.
> Parallelism would mean that any subset of subtasks from any task can
> be performed at each step.
> 
> 
> In all cases, the whole task is completed when all subtasks are completed.
> 
> Is this the intended meaning?
> 
> Are disabling, enabling and suspend-resume? It seems to me that a
> reasonable semantics can be given only for the binary case. Then,
> notationally, one could also indicate a chain of disabling, enabling,
> etc. But if we consider them as n-ary, without imposing an order, it
> is not clear what is enabling what, as I do not see a natural notion
> of distribution for these operators). If we are imposing an order, are
> we saying that T1>>T2>> … TN means that T1 enables T2 which enables
> .... which enables TN, or that T1 enables the fact that T2 enables ...
> that enables the fact that TN-1 enables TN. I guess the intended
> meaning is the first, which is however a chaining of binary relations.
> (This is different from the previous set of operators, which are
> naturally distributive)
> 
> I am not sure we really need the user and abstraction tasks type. How
> are we checking that the user is planning or doing some
> problem-solving? From the operational view, we can only specify the
> system and the interaction activities.
> 
> Concerning the definition of ConditionLiteral, I am not very happy
> with the fact that it has two attributes, only one of which is to be
> used at each time? Why not use ValueSpecification from the UML2
> metamodel, which can then be a LiteralSpecification, an Expression, an
> InstanceValue (for reference types) or even an OpaqueExpression
> (written in some executable language). This is what actually happens
> in UML2 when one expresses constraints by providing
> ValueSpecifications.
> 
> talk to you tomorrow!!
> 
> best
> paolo
> 
> 2012/7/16 Dave Raggett <dsr@w3.org>:
>> This is a call for comments on publishing the following document as a
>> First Public Working Draft:
>> 
>>  http://www.w3.org/2011/mbui/drafts/task-models/
>> 
>> My aim is to ask for a formal resolution in this week's MBUI telecon to
>> publish the document.
>> 
>> p.s. this was derived from the Google Doc, although it took quite a bit
>> of work!
>> --
>> Dave Raggett <dsr@w3.org> http://www.w3.org/People/Raggett
>> 
>> 
> 
> 
> 
> -- 
> Paolo Bottoni
> 
> Associate Professor of Computer Science
> 
> Email: bottoni@di.uniroma1.it
> 
> Website: http://w3.uniroma1.it/dipinfo/scheda_docente.asp?cognome=Bottoni&nome=Paolo
> 
> Phone: +39 06 49918426
> 
> Fax: + 39 06 8541842
> 
> 
> 
> Important conferences:
> 
> http://www.etaps.org/
> 
> http://www.diagrams-conference.org/2012/
> 
> http://vlhcc2012.di.unisa.it/
> 
> http://www.informatik.uni-bremen.de/icgt2012/
> 
> http://www.dsmforum.org/events/GMLD12/
>