Two Stage Fuzzy Flow Shop Scheduling to Minimize Rental Cost with Job – Block Criteria

In this paper we consider two stage flow shop scheduling to minimize the total rental cost of machines for n-jobs in fuzzy environment. The processing time of jobs and setup time for machines are uncertain. The fuzzy triangular membership function is used to describe uncertain processing times and setup times. Further, the restriction of equivalent job-block on job processing is also considered. The objective of the paper is to develop a new heuristic algorithm to minimize the rental cost of machines which is simple and straight forward. A numerical illustration explaining the computational process of the proposed algorithm is also given. Keywords: fuzzy processing time, fuzzy setup time, rental cost, average high ranking, utilization time and equivalent job –bloc