Integrated temporal reasoning with periodic events

In many areas of Computer Science, including planning, workflows, guideline s, and protocol management, one has to deal with abstract plans, procedures , or schedules involving temporal constraints between classes of actions th at have to be repeated at periodic times and may he instantiated in differe nt ways for different executions of the plans (procedures, schedules). In t his paper we propose an integrated framework to deal with both qualitative temporal constraints on classes of actions and temporal constraints between instances of actions, in which it temporal reasoning is used to amalgamate both types of constraints and to check their consistency. In particular, w e consider an expressive formalism to deal with temporal constraints betwee n classes of actions (with special attention to periodic actions) which tak es into account different components such as frame times, numeric quantific ation, periods, and qualitative relations. We define the notions of (contex tual) concretization of qualitative temporal constraints between classes an d use this notion to formally define the consistency of a knowledge base of temporal constraints between classes and a set of temporal constraints on instances, and to define the algorithm for checking such a consistency. An application for scheduling lessons in a school is shown in an example.