Re: [OWL-S] Process subClassOf IntervalEvent

On Jan 16, 2004, at 9:47 AM, Austin Tate wrote:

> At 09:27 16/01/2004 -0500, Bijan Parsia wrote:
>> So, it follows that AtomicProcesses aren't instants, which, while I 
>> accept that, could perhaps complicate some aspects of reasoning with 
>> them. (E.g., while it's great if you know that an AP is going to take 
>> up a certain amount of time, since you may be trying to figure out 
>> the overall time for a some composition, but you typically don't 
>> want, i take it, (relevant) change to happen during the AP (at least, 
>> from "inside" the AP).)
>
> Of course you must allow for this in general.

In some sense, yes. Part of the question is what is the common case, or 
rather, what do we intend to model with APs. They seem relevantly 
simple to Atomic activities in PSL.

I'm unclear how the "instantaneous" nature of APs affects APs executing 
in parallel.

>   While some atomic process or activity is taking place there will be 
> other services that might interact in some ways and you have to model 
> the possible interactions in many domains.

It definitely seems to be the case that if parallel processes are to be 
properly Atomic, in this sense, that they have to be independent (in 
the sense of not affecting each other, even indirectly). This is, 
perhaps, plausible for various parallel programming languages that 
prevent mutation of data structures, but not so much for services.

> We often have range constraints that go across from the begin time 
> point of an activity to the end time point of the activity which can 
> act as a protection (or constraint checking) condition on external 
> state changes that matter.

That could be interesting, especially if (partially) derivable from the 
AP description.

Cheers,
Bijan Parsia.

Received on Friday, 16 January 2004 10:19:09 UTC