Modeling of Multi-Level Capacitated Lot-Size Scheduling Problem | Science Publications

American Journal of Applied Sciences

Diyana A. Mahad¹  Tan S. Ching¹  Zuhaimy Ismail¹ 

关键词: Material Requirement Planning (MRP);    lot-sizing problem;    scheduling problem;    integer programming;    multi-level capacitated;    sub-optimal schedule;    cumulative demand;   

DOI  :  10.3844/ajassp.2011.290.296

学科分类：自然科学（综合）

来源: Science Publications

【 摘 要 】

Problem statement: Lot-size is the clustering of items for transportation or manufacturingprocesses occurring at the same time. The issue in lot-size problem is to design production processesso that the feasible production quantities are equal to customer demand quantities and the timing ofproduction is such that inventory positions are almost zero. Approach: In this study, we explore themulti-level lot-size and scheduling problem. It is on a multi-level capacitated lot-size problem orknown as the multi-level lot-size problem with bottlenecks. Two models were introduced to solve themulti-level lot-size problem namely the Billington model and Alf Kimms model. Using these models,a simple heuristic method was designed to solve a multi level capacitated lot sizing schedulingproblem. Results: In this study, we showed that Alf Kimms model is more efficient than Billingtonmodel. The result given by Alf Kimms model is always feasible without further modification unlikethe Billington model. This is due to the way the constraint is devised to ensure the inventory balance.The constraint used in Alf Kimms model ensures that inventory in hand is always sufficient to fulfillthe demand occurred in each period. However, the use of this constraint in Billington model is toensure that the total production for each item is always greater than or equal to the total externaldemand in the time horizon. Therefore, without some form of modification, the result given byBillington model will be infeasible production plan. Conclusion: A comparative study between thesemodels shows that both models were successfully devised to solve capacitated multi-level lot sizingproblem with the objective function to minimize the total holding costs and setup- cost. This study alsoshows that the production schedule will always start at the last period because this will give the lowestcosts and it also shows that Alf Kimms model gives a set of feasible sub-optimal schedule compare toBillington model.

【 授权许可】

Unknown