Optimization of Job Shop Scheduling Problem

Abstract

Timely and reliable delivery is becoming a more important factor for manufacturing companies since customer satisfaction becomes the paradigm of world class manufacturers. In some industries, keeping due dates is the bottom line for survival. But due to the NP-hard combinatory characters of the job shop scheduling problems, Hibret Manufacturing and Machine Building Industry (HMMBI) has faced the problem to determine the optimal schedules that minimizes the job completion time and thus failed to meet the promised delivery due date. Therefore, determining the optimal schedule that minimizes the makespan of the job using a shifting bottleneck heuristic was the aim of this study. Secondary data was collected from the production route sheets and Lekin® scheduling software is employed for comparing solution of different heuristics. The findings of the study showed that the shifting bottleneck (DASH) results in a total makespan of 23 hours with 6 hours (20.69%) improvement as compared to the current scheduling system that the HMMB uses.