基于变邻域搜索的热轧圆钢批量调度多目标优化方法
Variable neighborhood search based multi-objective optimization method for batch scheduling of hot-rolled bars
-
摘要: 针对热轧圆钢的批量调度问题,考虑实际生产中工艺规程和交货期对轧制单元连续加工的影响,建立了以最小化设备调整时间、拖期生产惩罚和钢种跳跃惩罚为优化目标的数学模型,并设计了一种嵌入EDD规则的变邻域搜索算法.算法首先结合模型的约束特征,采用约束满足技术生成初始解;根据实际生产需求,将最小化设备调整时间作为主要目标,设计变邻域搜索算法实现目标优化,其中,运用混合算子构造邻域结构和局部搜索,并引入模拟退火接受准则来控制迭代过程中产生的新解;同时,为了最小化拖期惩罚和钢种跳跃惩罚,在求解过程中嵌入了EDD规则以及钢种排序规则.实验结果表明,模型和算法是可行且有效的.Abstract: A batch scheduling problem of hot-rolled bars was discussed according to the influences of process conditions and due date on the continuous production of rolling units. A mathematical model with three objectives to minimize the setup time, tardiness penalty and steel grade bounce penalty was constructed, and a method of the variable neighborhood search algorithm embedding the earliest due date first (EDD) rule was proposed to solve the model. In consideration of constraints in the model, an initial solution was generated by constraint satisfaction technology. Then, to meet the actual production needs, a variable neighborhood search method was designed to minimize the setup time, which is considered as a primary objective. In this algorithm, a hybrid operator is applied in sha-king and local search, and the idea of simulated annealing is introduced to take control of the acceptance of new solutions. Meanwhile, in order to minimize the tardiness penalty and the steel grade bounce penalty, the earliest due date first rule and the steel grade sorting rule are applied. Experiment results show that the model and the algorithm are feasible and effective.