Temporal Constraint Satisfaction Techniques in Job Shop Scheduling Problem Solving

We describe a restriction of Dechter, Meiri and Pearl's TCSPs (Temporal Constraint Satisfaction Problems) suuciently expressive to represent any job shop scheduling problem. A solver based on the restriction is then described, which is similar to Ladkin and Reinefeld's qualitative interval network solver; except, however, that the ltering method used during the search is not path consistencybut either ULT (Upper-Lower Tightening) or LPC (Loose Path-Consistency), which are both less eeective but have the advantage of getting rid of the so-called \fragmentation problem".