基于HGA的冲压车间生产计划与调度的集成优化

根据车身厂冲压车间和生产库房的实际情况，研究了冲压件成批生产的Job—shop车间生产计划和凋度的集成优化问题，给出该问题的非线性混合整数规划模型，并采用混合遗传算法进行求解。遗传算法中，给出一种新的启发式规则来改善初始解集，通过与递阶分解方法进行比较，得出该算法对求解该类问题有着很好的效果。     

基于HGA的冲压车间生产计划与调度的集成优化

根据车身厂冲压车间和生产库房的实际情况,研究了冲压件成批生产的Job-shop车间生产计划和调度的集成优化问题,给出该问题的非线性混合整数规划模型,并采用混合遗传算法进行求解。遗传算法中,给出一种新的启发式规则来改善初始解集,通过与递阶分解方法进行比较,得出该算法对求解该类问题有着很好的效果。     

Job- shop 提前/拖期调度问题的研究

基于模糊控制和遗传算法,提出了求解Ｊｏｂ－ｓｈｏｐ提前／拖期间问题的联合算法,用遗传算法确定可行调度序列,然后用模糊控制器对开工时间加以调整,模糊控制的引入为有效地求解Ｊｏｂ－ｓｈｏｐ提前／拖期调度总理２提供了新的方法,仿真实验证明了联合自救的有效性。     

基于遗传算法的一类Job—shop调度

针对遗传算法解决生产路径不固定的调度问题所遇到的困难，提出一种遗传编码方式，并相应采用新的遗传算子。应用于某冷轧厂的精整计划钢卷调度问题，进行了仿真分析。     

用约束满足自适应神经网络和有效的启发式算法解Job—shop调度问题

提出一种用约束满足自适应神经网络结合有效的启发式算法求解Ｊｏｂ－ｓｈｏｐ调度问题,在混合算法中,自适应神经网络具有在网络运行过程中神经元的偏置和连接权值自适应取值的特性,被用来求得调度问题的可行解,启发式算法分别和来增强神经网络的性能,获得确定排序下最优解和提高可行解的质量。仿整表明了本文提出的混合算法的快速有效性。     

Job—shop多机实时调度的并行算法

本文针对ＭＩＭＤ并行机对一般的Ｊｏｂ－ｓｈｏｐ调度提出实时调度的并行算法，通过分析复杂性和加速比以及实例，说明并行算法对求大批工件多台机器加工的最优调度的优越性。     

基于DNA进化算法的车间作业调度问题研究

针对遗传算法解决车间作业调度问题时存在早熟收敛的缺点,采用一种新型进化算法——DNA进化算法解决车间作业调度问题.将算法从连续优化问题拓展用于解决离散优化问题,并将其成功地应用于Job shop生产调度.采用了著名的M u th和T hom pson标准问题FT 10进行了验证.仿真结果表明,与遗传算法相比,该算法简单有效,不仅具有很好的求解性能,而且具有更快的收敛速度和全局搜索能力.     

汽车装配线生产计划与调度的集成优化方法

为提高汽车装配线的生产效率,优化资源配置,研究了汽车装配线生产计划和调度的集成优化问题,给出了该问题的混合整数规划模型.利用分枝定界算法和单纯型法求得问题的粗生产计划.通过将模拟退火算法和快速调度仿真相结合,探讨了一种新的启发式算法.然后基于已求得的粗生产计划,针对三种不同寻优组合论述了该算法的实现.将该算法应用于实际算例,仿真结果表明该算法对求解此类问题有着很好的效果.     

柔性作业车间生产计划与调度集成优化求解策略

针对柔性作业车间(Flexible job-shop, FJS)生产计划(Production planning, PP)与调度紧密衔接的特点, 建立了生产计划与调度集成优化模型. 模型综合考虑了安全库存、需求损失及工件加工路线柔性等方面因素. 提出了一种基于拉格朗日松弛(Lagrangian relaxation, LR)的分解算法, 将原问题分解为计划子问题与调度子问题. 针对松弛的生产计划子问题, 提出一种新的费用结构, 以保证生产计划决策与实际情况相符, 并设计了一种变量固定—松弛策略与滚动时域组合算法进行求解. 对于调度子问题中的加工路线柔性问题, 提出了一种新的机器选择策略. 通过数值实验验证了模型与算法的有效性.     

汽车同步装配线生产计划与调度集成优化汽车同步装配线生产计划与调度集成优化

为克服传统的"自顶向下"方式下生产计划与调度不协调的缺陷,针对汽车同步装配线,构造了生产计划与调度集成优化混合整数规划模型,并采用拉格朗日松弛法将其分解为批量计划及调度等子问题.将调度子问题转化为与时间相关的旅行商问题,并采用dynasearch算法求解.对于拉格朗日对偶问题,采用均衡方向策略法求解.仿真实验结果验证了模型及算法的有效性.     

A genetic local search algorithm for minimizing total weighted tardiness in the job-shop scheduling problem

This paper considers the job-shop problem with release dates and due dates, with the objective of minimizing the total weighted tardiness. A genetic algorithm is combined with an iterated local search that uses a longest path approach on a disjunctive graph model. A design of experiments approach is employed to calibrate the parameters and operators of the algorithm. Previous studies on genetic algorithms for the job-shop problem point out that these algorithms are highly depended on the way the chromosomes are decoded. In this paper, we show that the efficiency of genetic algorithms does no longer depend on the schedule builder when an iterated local search is used. Computational experiments carried out on instances of the literature show the efficiency of the proposed algorithm.     

Capacity planning in job-shop environment

Presented here is a computerized capacity planning system for the IBM Microcomputer family. The system maintains the profile of the job shop in a data base along with data pertinent to various products that can be manufactured in the shop. Projected orders for the planning period are input to the system with their associated quantities and delivery dates. The system uses the forward and backward loading rules in generating capacity loading scenarios. User selects the best course of action which may satisfy delivery dates subject to the limitations of the work centers. Efficiency figures are provided to aid the user in his/her decision.     

柔性作业车间调度中的组合遗传优化研究

针对柔性作业车间调度问题,提出一种组合遗传算法。该算法在种群初始化、选择、交叉、变异各阶段,组合使用各种不同的策略。针对机器编码部分的交叉,提出一种基于工件的机器交叉算子,用以改进机器分配部分随机交叉引起的对父代优秀基因继承不足的缺陷。通过对典型算例的计算以及与其他文献的研究成果比较,证明该算法的优良性能。     

Heuristic factory planning algorithm for advanced planning and scheduling

This study focuses on solving the factory planning (FP) problem for product structures with multiple final products. In situations in which the capacity of the work center is limited and multiple job stages are sequentially dependent, the algorithm proposed in this study is able to plan all the jobs, while minimizing delay time, cycle time, and advance time. Though mixed integer programming (MIP) is a popular way to solve supply chain factory planning problems, the MIP model becomes insolvable for complex FP problems, due to the time and computer resources required. For this reason, this study proposes a heuristic algorithm, called the heuristic factory planning algorithm (HFPA), to solve the supply chain factory planning problem efficiently and effectively. HFPA first identifies the bottleneck work center and sorts the work centers according to workload, placing the work center with the heaviest workload ahead of the others. HFPA then groups and sorts jobs according to various criteria, for example, dependency on the bottleneck work center, the workload at the bottleneck work center, and the due date. HFPA plans jobs individually in three iterations. First, it plans jobs without preempting, advancing, and/or delaying. Jobs that cannot be scheduled under these conditions are scheduled in the second iteration, which allows preemption. In the final iteration, which allows jobs to be preempted, advanced, and delayed, all the remaining jobs are scheduled. A prototype was constructed and tested to show HFPA's effectiveness and efficiency. This algorithm's power was demonstrated using computational and complexity analysis.     

Integration of process planning and production scheduling based on genetic algorithm

Lacking of flexibility in the traditional workshop production, a genetic algorithm is proposed to implement the integration of process planning and production scheduling. In this paper, the processing routes and processing machine are selected through chromosome crossover and mutation, in order to implement the optimal scheduling of the flexible workshop production. Meanwhile, a performance test about the integration of process planning and production scheduling is implemented, and the results shows that the genetic algorithm is efficient to obtain optimal or near optimal process routes which can meet the requirements of production scheduling.     

Application of game theory based hybrid algorithm for multi-objective integrated process planning and scheduling

Process planning and scheduling are two key sub-functions in the manufacturing system. Traditionally, process planning and scheduling were regarded as the separate tasks to perform sequentially. Recently, a significant trend is to integrate process planning and scheduling more tightly to achieve greater performance and higher productivity of the manufacturing system. Because of the complementarity of process planning and scheduling, and the multiple objectives requirement from the real-world production, this research focuses on the multi-objective integrated process planning and scheduling (IPPS) problem. In this research, the Nash equilibrium in game theory based approach has been used to deal with the multiple objectives. And a hybrid algorithm has been developed to optimize the IPPS problem. Experimental studies have been used to test the performance of the proposed approach. The results show that the developed approach is a promising and very effective method on the research of the multi-objective IPPS problem.     

Lagrangian bounds for just-in-time job-shop scheduling

We study the job-shop scheduling problem with earliness and tardiness penalties. We describe two Lagrangian relaxations of the problem. The first one is based on the relaxation of precedence constraints while the second one is based on the relaxation of machine constraints. We introduce dedicated algorithms to solve the corresponding dual problems. The second one is solved by a simple dynamic programming algorithm while the first one requires the resolution of an NP-hard problem by branch and bound. In both cases, the relaxations allow us to derive lower bounds as well as heuristic solutions. We finally introduce a simple local search algorithm to improve the best solution found. Computational results are reported.     

An active learning genetic algorithm for integrated process planning and scheduling

In traditional approaches, process planning and scheduling are carried out sequentially, where scheduling is done separately after the process plan has been generated. However, the functions of these two systems are usually complementary. The traditional approach has become an obstacle to improve the productivity and responsiveness of the manufacturing system. If the two systems can be integrated more tightly, greater performance and higher productivity of a manufacturing system can be achieved. Therefore, the research on the integrated process planning and scheduling (IPPS) problem is necessary. In this paper, a new active learning genetic algorithm based method has been developed to facilitate the integration and optimization of these two systems. Experimental studies have been used to test the approach, and the comparisons have been made between this approach and some previous approaches to indicate the adaptability and superiority of the proposed approach. The experimental results show that the proposed approach is a promising and very effective method on the research of the IPPS problem.     

基于改进型批决策与调度建模的生产计划调度系统的研究

热轧型钢生产工艺复杂,其生产中极易出现由于计划调度安排不当而产生的交货期延误、库存超负荷等问题。针对以上问题研究设计了MES生产计划调度系统,改进了批决策调度策略用于数学建模,利用自适应遗传算法求解生产调度计划。以此为基础,为某热轧企业设计实现了生产计划调度系统,并通过真实的热轧型钢订单、原料、设备等数据,对模型改进前后的计划编制方法进行模拟与比较,验证了利用该改进型批决策与调度模型编制的热轧型钢生产调度计划可节省生产时间、降低设备调度时间,以此来指导热轧型钢的生产可切实减少交货延误和减少库存占用率,并提高企业利润率。