Fuzzy Time Constraint Propagation Mechanism for Workflow Nets

A workflow model should describe as well as analyse time and the temporal behaviour of resources and activities. In general, typical temporal phenomena include activity execution delays, limits to the occurrence of valid intervals over the activities, limit to valid intervals over resources (limits to recourse life cycle), limits to duration of process execution, time distance between two activities, etc. In this study a workflow net model incremented with fuzzy intervals to describe the duration of activities and waiting times is presented. To define the execution of activities minimum and maximum intervals, a time constraint propagation mechanism is proposed.