- From: Austin Tate <a.tate@ed.ac.uk>
- Date: Wed, 28 Apr 2004 09:09:54 +0100
- To: "Public-Sws-Ig@W3. Org" <public-sws-ig@w3.org>
In our AI planning work, we just call them all world state conditions and world state effects. We do not talk about them as pre-, post- etc. Conditions on the world state can be stated as applying at the begin time point of an activity or the end time point. Notice I say "at" the time point... rather than before or after the time point by the way. I.e. its an instantaneous point at which the conditions are stated as holding. Effects that purport to change the world state can occur also at the begin time point or the end time point. Of course you have to decide whether to believe you model of effects or whether to set up condition monitoring mechanisms to ensure they actually occurred. I think its a serious limitation to think only of conditions on the begin time point and effects on the end time point. Even if we also allow conditions on the end time point, we still leave out effects on the world state that can or should be modelled as occurring earlier. We have to mess about a bit to be able to translate this more flexible conditions/effects model (which we have used in our planners for over 20 years) into OWL-S with its more limited view of IOPE. Austin -- Prof. Austin Tate, Artificial Intelligence Applications Institute, Informatics, University of Edinburgh, Appleton Tower, Crichton Street, Edinburgh EH8 9LE, UK Tel: +44 131 650 2732 Fax: +44 131 650 6513 E-mail: a.tate@ed.ac.uk
Received on Wednesday, 28 April 2004 04:08:38 UTC