- From: Jeff Dalton <jeff@inf.ed.ac.uk>
- Date: Fri, 25 Jun 2004 17:57:25 +0100 (BST)
- To: public-sws-ig@w3.org
Quoting Donal Murtagh <domurtag@cs.tcd.ie>: > The problem with planners is that compatibility of preconditions and > effects is based on (lexical) name matching. Although SHOP2 can > evaluate simple expressions such as ((eval (< ?n1 5)) in the > precondition of an operator, AFAIK, it is not possible to assert > an effect which is a conditional expression, e.g. to state that > "the effect of this process/operator is that (< ?n1 5) is true". Something like that could be treated in a planner as a constraint. I don't know off-hand of any planner that handles such numeric constraints, though some resource constraints might be equivalent. Also, a planner doesn't have to use name-matching. I don't see any reason why a description logic reasoner, for example, couldn't be used. I do wonder how existing reasonsers, such as Pellet, could be used, because planners want to reason about change over time. (has-colour block-A blue) might be true at one point, and false at another, while (has-colour block-A green) might become true. But perhaps this just reflects my ignorance of existing reasoners such as Pellet. > More generally, has there been any attempt to translate OWL-S > preconditions/effects to SHOP2 syntax? I hope to try something like that for O-Plan / I-Plan once its clearer how OWL-S preconditions and effects can be specified. I don't yet know how difficult it will be. -- Jeff
Received on Friday, 25 June 2004 12:57:28 UTC