COMPARATIVE ANALYSIS OF GROUP SCHEDULING HEURISTICS AND AN EVALUATION OF DUE DATE ASSIGNMENT POLICY IN A CELLULAR SYSTEM WITH FORBIDDEN EARLY SHIPMENT

Abstract

Recent progress in manufacturing systems research has identified the feature of forbidding early shipment (FES) of orders as a prevalent characteristic of real systems. The early/tardy problem is one of the most vexing pieces of the complex production scheduling decision process. So far most of the research has been on single-machine environments. This study proposes a comparative analysis of four group scheduling heuristics on the performance of flow shop cellular system with forbidden early shipment. In FES environment , the suppliers deliver materials to the system on a just-in-time basis and a completed order cannot leave the system earlier than the customer has specified. The effect of group scheduling heuristics like FCFS/FCFS, EDD/EDD, APT/SPT, ADD/EDD on the performance of cellular system are considered with the help of computer simulation using ProModeI, a manufacturing simulation software. The objective behind this study is to obtain best performing group scheduling- heuristics for the flow shop cellular system with FES environment having feature of shared workcentre. In order to achieve a goal of reduction in tardy orders the performance measures considered in this study are average tardiness, average percentage of tardy orders, average time in system ,average number of orders shipped and average work in process. The best performing heuristics provide guidance for schedulers in the selection of heuristics based on the shop conditions and the performance measure that are most important in their industry