Re: [poe] isNeccessaryFor

Hi @riannella is this a night shift today for you :-( ?

Re your comments above: I'm aware of this discussion but my conclusion
 is that isNessareyFor doesn't cover the needs. Why: 
- re POE UC 19: This UC defines that first a dynamic point in time is 
set (end of an event) and then this point in time is the starting 
point for a temporal delay, only after this delay the Action may be 
exercised. How to design constraints for that:
-- Constraint 1: define c1 using the Action Date Time Left Operand, 
odrl:gteq operator and a rightOperandReference providing dynamically 
the end-date/time of the event. But this c1 will only deliver a result
 if the constraint is evaluated close to the time of the end of the 
event and close to the time when the action should be exercised- 
therefore I still think this should be explicitly indicated.
-- Constraint 2: define c2 using - hm??? - a currently not existing 
Delay Period Left Operand, a odrl:eq operator and a right operand of 
30 minutes (for "may be used 30 minutes after the event has ended"). 
- Simple approach: combine c1 and c2 by an odrl:and as in fact both 
must be satified.
- The tricky thing of this design is: how to express that the 
starting-point-time of c2 is triggered by the 
date/time used as "end of event" in c1? A simple isNecessaryFor is not
 sufficient. We need an "evaluate the right operand only if the left 
operand constraint is satisified" relationship, named e.g. 
"ifSatisfiedEvaluate" (may need some pondering ...) -> c1 
odrl:ifSatisfiedEvaluate c2 sounds close to the intention.
- ... and we need a Left Operand Delay Period with a definition like 
"A period of time after which the Action may be exercised. The start 
of the period is triggered if another constraint is satisfied. This 
other constraint and the constraint using this Left Operand must be 
related by an odrl:ifSatisfiedEvaluate Constraint Relation." See also:
 Elapsed Time Left Operand - 
http://w3c.github.io/poe/vocab/#term-elapsedTime
- To make this clear: using odrl:ifSatisfiedEvaluate to combine two 
constraints requires special Left Operands which build on this 
relationship.
- re POE UC 16: this UC is not very clear what may be done each month:
 1 access only, or access for 1 day? Anyway: 
-- Constraint 1: define c1 using Action Date Time Left Operand with 
odrl:lteq operator and an explicit date/time in 7 years as right 
operand.
-- Constraint 2: define c2 using Recurring Time Interval Left Operand,
 odrl:eq operator and as right operand a period of 7 days. 
-- Constraint Relation: I think odrl:and is sufficient - as the UC 
does not define when the 1-month-period will start - its sound like: 
an exercised access triggers the period.



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Received on Thursday, 2 February 2017 14:17:52 UTC