JIT SCHEDULING RULES - A SIMULATION EVALUATION

Just-In-Time (JIT) production systems capitalize on simplicity and the ability of workers to make decisions in a decentralized manner. In a multiproduct Line operating under kanban control, the production worke r at a given station must schedule the different jobs awaiting process ing using information available locally. In practice, the first-come-f irst-sen ed (FCFS) rule is commonly used. Recent results reported in t he literature indicated that the shortest-processing-time (SPT) rule p erformed better than the FCFS rule. In this paper, we provide a simula tion evaluation of the performance of a number of scheduling rules ope rating under different JIT production scenarios. Our hypothesis is tha t there are differences in the relative performance of the scheduling rules under different production scenarios. We differentiate among the JIT scenarios by the extent of setup time reduction already carried o ut (as indicated by the ratio of setup to processing times), the amoun t of slack in the system (as measured by the number of kanbans circula ting), the extent to which uncertainty has been eliminated (as determi ned by the stochasticity of processing times), and the complexity of p roduction requirements (as specified by the product-mix in mixed-model assembly). In this way, this paper provides further insights into the performance of scheduling rules operating under different JIT product ion environments, thereby adding to the scope and depth of research in this particular aspect of JIT production systems. (C) 1998 Elsevier S cience Ltd. All rights reserved.