不确定条件下双目标组批生产的交货期设置研究

Due Date Assignment with Bi-objective Based on Batch Schedule under Uncertain Condition

交货期是调度方法的函数,因而具有不确定性.研究变批量、变批次、变生产能力下,单阶段、双目标有条件相容组批的交货期设置问题,将它转化为订单投放策略和调度模式研究.建立了一个基于目标的双目标订单投放策略数学模型.采用目标序列优先方法进行双目标求解,用两种调度模式求出区间值,进行最优交货期逼近.模式1:松弛掉产品加工约束条件,基于负荷考虑、给出离散生产模式下订单完工率最大的订单排序算法,算法综合考虑了任务紧急程度、可调度性、重要度和流程时间最短四个方面,得到区间的一个端点.模式2是有条件相容的启发式组批调度算法,即通过聚类计算将订单安排问题转化为多队列调度问题,将新来订单的投放转化为某个队列的插单和批量分割问题,不同队列中批的投产顺序由批中优先级最高的订单决定,并在能力约束下进行批量分割计算,得到区间的另一个端点,结合流程可靠性求出区间.实例证明,模式2的交货期设置小,订单完工率和生产率高.

Due date assignment is considered as function of schedule in this paper, so it is uncertainty. A kind of due date assignment with variable lot size, variable lots and variable capacity under single-stage with bi- objective of production system with compatible batch scheduling under certain condition is studied. To solve it ,we change the problem into strategy of order review and release and schedule mode. A math model of order review and release with biobjective is built first. Then the problem is changed into optimize solution search of bi-objective. To realizes it, a preferred target sequence is adopted to fit the bi-objective requirement. And two schedule mode is adopted to work out delivery interval to approach optimize delivery value at the same time .In schedule mode one , processing constraints is removed. Sorting algorithm of maximum accomplishments rate of order under discrete production mode is given in mode one. In the algorithm, those are took into accounted which include the urgency of the task, schedule flexible, importance of order and the shortest flow time .Thus ,one of interval value is get. In schedule mode two, which is called compatible batch scheduling under certain condition , the due date assignment is changed into problem of order clustered into batch and the batch sorting . The clustering problem is then changed into multi-queue scheduling, and new order due date assignment is changed into a order be put into a queue and inserted in certain segmentation of one queue with batch splitting. The delivery sequence of batch is decided by the highest priority order in that batch. And splitting of lots size is calculated under capacity limited. Thus another interval value is get. According flow stable probability, the interval value is calculated. An experiment of a case is designed. The result shows that the completion rate of orders and production rate of production system are higher in schedule mode two than in schedule mode one, and the due date assignment can be shorter than mode one.