Rescheduling of parallel machines with stochastic processing and setup times

• Generating repair rules to absorb disruptions/new job arrivals and maintain schedule's quality and stability.
• Testing the rules under stochastic times using discrete-event simulation.
• Testing the rules under the unrelated parallel machine scheduling problem with sequence-dependent setup times.

This paper tackles rescheduling for the unrelated parallel machine problem with sequence dependent setup times and different rates of breakdowns or urgent jobs arrivals. The jobs’ processing and setup times are stochastic for better depiction of the real world. A new repair rule which will be referred to as Minimum Weighted Cmax Difference (MWCD) is developed and compared to existing algorithms using simulation.The rules are evaluated based on both schedule quality and stability. Design of Experiments and optimization were used with simulation to generate optimal values for MWCD's parameter. The results and analysis obtained from the computational experiments proved the superiority of the proposed repair rule MWCD over the other algorithms presented.