- From: Feng Pan <pan@ISI.EDU>
- Date: Mon, 3 May 2004 21:08:34 -0700 (PDT)
- To: David Martin <martin@AI.SRI.COM>
- Cc: Jerry Hobbs <hobbs@ISI.EDU>, public-sws-ig@w3.org
Hi David, Thanks for copying the email to me. Yes, I'm on public-sws-ig@w3.org. Currently the time ontology is used in Process.owl as follows: Class: Process subclass IntervalEvent ControlConstruct subclass IntervalEvent ObjectProperty: timeout: ProcessComponent --> IntervalThing timeoutAbsolute: ProcessComponent --> InstantThing In class ProcessComponent's definition (restriction on property): begins ends timeout timeoutAbsolute After you remove Process subclass IntervalEvent ControlConstruct subclass IntervalEvent "begins" and "ends" temporal property restrictions will have to be removed (or re-defined) from the definition of ProcessComponent, since they are based on the the above subclass relationship. About "timeout" and "timeoutAbsolute", based on Mark Burstein's email: > Process Instances now represents either a set of unrelated intervals > (like the old process class) or else something that is not an event at > all, but is just a spec for one. it makes sense to me to still keep them as possible temporal properties of ProcessComponent. > I've also removed the cardinality restrictions on temporal properties, > which were based on these subclass relationships. I don't understand why you (only) removed the cardinality restrictions on temporal properties (which I guess are "begins" and "ends", right?). The problem is the whole restriction, not the cardinality, as they are using owl:maxCardinality="1"... Thanks, Feng On Mon, 3 May 2004, David Martin wrote: > Bijan Parsia wrote: > > > > > I notice that: > > > > <owl:Class rdf:ID="Process"> > > <rdfs:comment> The most general class of processes </rdfs:comment> > > <rdfs:subClassOf rdf:resource="&time;#IntervalEvent"/> > > ... > > > > 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).) > > > > More importantly, I don't think Processes, as we've currently defined > > them (i.e., as Process *definitions*) are TemporalThings at all. For > > example, it makes no sene to say that one definition is *before* another > > (it does make sense to say that this or that Process occurrence is > > before that other one, or that this Process execution is before this > > other one). > > OK, later today I've planning to remove both > Process subclass IntervalEvent > and > ControlConstruct subclass IntervalEvent > > from the developing 1.1 Process.owl file > (which, please note, is an incomplete, inconsistent *draft* at present). > > I've also removed the cardinality restrictions on temporal properties, > which were based on these subclass relationships. > > (This removal of the time ontology use) is one of the more regrettable > aspects of our switch to PAI.) > > Of course, if and when we develop an ontology of process "execution > traces" (as we have discussed in the past), we can again use the time > ontology in this way, with execution traces. > > In the meantime, I'm not clear what, if anything, we can say about time > in Process.owl. > > Feng, do you have any guidance regarding this? > > Thanks, > David > > > > >
Received on Tuesday, 4 May 2004 00:15:41 UTC