求解多目标作业车间调度问题的双种群遗传算法

针对多目标作业车间调度问题,提出一种将正逆序调度方法与生成调度活动的遗传算法相结合的双种群遗传算法.该算法利用活动调度缩减解空间,提出采用正、逆序遗传调度算法分别在不同种群优化不同目标函数,将多目标问题分解成多个单目标问题.在进化过程中,通过个体迁移算子加快多个目标的并行搜索,并提出了一种构造Pareto解集的精英锦标赛法则.通过基于Benchmark算例的仿真实验,验证了该算法求解多目标作业车间调度问题的有效性.     

考虑多目标的工艺规划与调度集成问题研究

针对工艺规划与调度集成问题在多目标优化方面的不足,考虑将多目标优化集成到工艺规划与调度集成问题中。以最长完工时间、加工成本及设备最大负载为优化目标,对该多目标工艺规划与调度集成问题进行建模,并提出了一种非支配排序遗传算法,鉴于加工信息的多样性,使用多层结构表示可行解,对该算法的选择及遗传操作等步骤进行了设计。最后,以实例验证了上述模型的正确性及算法的有效性。     

超启发式遗传算法柔性作业车间绿色调度问题研究

针对启发式算法通用性较差的问题,建立了多目标柔性作业车间绿色调度模型,设计了一种超启发式遗传算法对问题进行求解.首先,建立了以最大完工时间和最小能耗为目标的柔性作业车间绿色调度模型,并设计了超启发式遗传算法对模型进行优化求解;然后,对于高层启发式策略采用遗传算法,随机生成初始种群,对种群进行了选择、交叉和变异操作,并且...     

基于改进非支配排序遗传算法的多目标柔性作业车间调度

采用多目标进化算法解决具有工件释放时间、工件目标差异的柔性作业车间调度问题。依据实际制造系统中存在较多的最大完工时间、平均流经时间、总拖期时间、机器总负荷、瓶颈机器负荷和生产成本性能指标,建立多目标柔性作业车间调度模型。针对柔性作业车间调度问题的特点,设计一种扩展的基于工序的编码及其主动调度的解码机制,以及初始解产生机制和有效的交叉、变异操作;针对非支配排序遗传算法(Non-dominated sorting genetic algorithm II,NSGA-II)在非支配解排序和精英选择策略方面的不足,设计一种改进的非支配排序遗传算法,应用改进的算法求解柔性作业车间调度问题得到一组Pareto解集,并运用层次分析法选出最优妥协解。通过测试基准和模拟实际生产的实例,验证提出算法的可行性和有效性。     

基于遗传算法的云设计资源调度算法

云设计资源调度是构建云设计资源平台的关键技术之一.提出以服务请求的总响应时间、总服务成本和服务质量为目标的多目标优化调度模型,该模型以服务请求的满足度和云设计资源的最大负载为约束,同时考虑云设计资源的服务状态.依照该模型提出一种基于遗传算法的云设计资源调度算法,最后给出了该算法的应用实例.     

异常事件监控驱动的动态再调度研究

针对实际生产中由于各种异常事件导致初始调度计划不能适应动态生产环境的问题,提出了一种基于异常事件监控的动态再调度优化策略。建立异常事件监控系统与动态再调度之间的关联框架,通过监控获知异常事件的发生并以此来驱动再调度。再调度是运用滚动窗口技术把动态变化的过程转换为连续的静态调度区间,然后用Pareto的多目标遗传算法对每个区间进行调度优化。根据异常事件的不同,设计了相应再调度机制(滚动窗口的更新、算法参数的初始化),又根据动态调度问题的特性,设计了有效的多目标选择操作和遗传操作,最后通过实例验证这种动态调度的有效性和可行性。     

多工艺路线多资源多目标的作业调度优化

针对多工艺路线多加工资源多目标的作业调度问题,提出了一种启发式活动调度算法,将该方法与多目标遗传算法及模糊优选技术相结合,得到了一种新调度算法.基于工序的染色体编码方法和基于活动启发式算法的交叉算子的运用,有效地缩小了遗传算法的搜索空间.将随机产生的权系数与模糊优选技术相结合,有助于遗传算法搜索到多个优良的调度方案,这为决策者得到最满意的调度方案提供了保证.仿真结果表明该算法是可行的,与国外学者的同类研究相比,具有一定的优越性.     

基于NSGA-Ⅱ算法的液压元件多目标柔性作业调度研究

为解决液压元件制造车间生产调度过程混乱的问题,提出一种基于NSGA-Ⅱ的多目标柔性生产调度优化算法,并建立了相关的数学模型。采用非支配排序和精英储备策略,并设计了算法的编码解码以及交叉、选择和变异的遗传算子。最终通过实例分析,将得出的基于基本加工时间、设备负荷率和生产成本的全局最优解与传统遗传算法优化值进行对比,可见此算法可提高液压制造车间的生产调度效率。     

一种求解多目标柔性作业车间调度问题的改进元胞遗传算法

针对最小化最大完工时间、最大机床负荷及总机床负荷的多目标柔性作业车间调度问题,提出一种带有局部搜索策略的自适应元胞遗传算法。该算法在每完成一次种群迭代后,对种群的平均收敛速度进行计算,确定出合适的选择压。根据种群选择压的大小对种群的拓扑结构进行自适应改变。为了减小邻域搜索空间,结合车间调度问题的特点,借鉴正交设计思想设计了基于正交规则的局部搜索策略。通过4个经典多目标柔性车间调度问题的仿真实验以及与其他算法的比较,说明了该算法的有效性和可行性。     

基于机床加工匹配特性的混合流水车间绿色生产调度

针对混合流水车间绿色生产过程中的设备选择和调度目标匹配问题,提出基于机床加工特性的多目标调度模型和改进遗传算法。该算法建立了混合流水车间调度的时间、能耗与成本优化模型,采用模糊隶属方法描述了机床加工特性,在遗传算法求解过程中通过机床加工特性隶属度与调度目标的权重系数匹配关系,建立了自适应的交叉、变异和优势保留策略,在每一代迭代中提高在调度目标方向上的选择压力,加速收敛。通过实例分析对比了不同算法的优化结果,从而验证了模型及算法的有效性,并提出了高效、节能、经济和综合4种调度生产模式,为混合流水车间绿色生产提供了指导。     

Development of a multiobjective GA for advanced planning and scheduling problem

In this paper, we consider an advanced planning and scheduling (APS) problem in manufacturing supply chain. The problem was formulated with mixed integer programming and three objectives are taken into account. To solve the APS model, a multiobjective genetic algorithm with local search is presented to find the Pareto optimal solutions. The proposed algorithm makes use of the principle of nondominated sorting, coupled with the use of a metric for normalized crowding distance. Local search technique is used to improve the efficiency. The proposed algorithm was compared with two other multiobjective genetic algorithms from the literature. Performance of these heuristics has been tested on ten problems in three scenarios. The computational results demonstrate the effectiveness and efficiency of the proposed approach and indicate that the presented algorithm outperforms previous work for APS problems.     

Genetic algorithm with new encoding scheme for job shop scheduling

In so many combinatorial optimization problems, job shop scheduling problems have earned a reputation for being difficult to solve. Genetic algorithm has demonstrated considerable success in providing efficient solutions to many nonpolynomial-hard optimization problems. In the field of job shop scheduling, genetic algorithm has been intensively researched, and nine methods were proposed to encode a chromosome to represent a solution. In this paper, we proposed a novel genetic chromosome-encoding approach; in this encoding method, the operation of crossover and mutation was done in three-dimensional coded space. Some big benchmark problems were tried with the proposed three-dimensional encoding genetic algorithm for validation and the results are encouraging.     

A new parallel genetic algorithm for solving multiobjective scheduling problems subjected to special process constraint

This study presents a multiobjective scheduling model on parallel machines (MOSP). Compared with other scheduling problems on parallel machines, the MOSP is distinct for the following characteristics: (1) parallel machines are nonidentical, (2) the type of jobs processed on each machine can be restricted, and (3) the multiobjective scheduling problem includes minimizing the maximum completion time among all the machines (makespan) and minimizing the total earliness/tardiness penalty of all the jobs. To solve the MOSP, a new parallel genetic algorithm (PIGA) based on the vector group encoding method and the immune method is proposed. For PIGA, its three distinct characteristics are as follows: Firstly, individuals are represented by a vector group, which can effectively reflect the virtual scheduling policy. Secondly, an immune operator is adopted and studied in order to guarantee diversity of the population. Finally, a local search algorithm is applied to improve the quality of the population. Numerical results show that it is efficient, can better overcome drawbacks of the general genetic algorithm, and has better parallelism.     

Two meta-heuristics for solving a new two-machine flowshop scheduling problem with the learning effect and dynamic arrivals

This paper develops a new mathematical model and proposes two meta-heuristics for solving a two-machine flowshop scheduling problem that minimizes bi-objectives, namely the total idle time and the mean deviation from a common due data. In this paper, we assume the arrival time of jobs is dynamic, in which each job has a time window and can arrive in its time window randomly. We also assume the learning effect on the processing times considering as a position-dependent effect. Since the problem is an NP-hard one, we present a multiobjective genetic algorithm (MOGA) and a multiobjective simulated annealing (MOSA) algorithm to solve the given problems. The computational results confirm that the proposed MOGA has a better solution in comparison with the proposed MOSA, especially in large-sized problems.     

基于博弈论的虚拟制造网络车间调度优化方法

针对虚拟制造网络中的车间调度问题,提出了一个非合作博弈调度优化模型,将车间调度问题转化为一场博弈。在分析该博弈调度模型的理想纳什均衡存在性的基础上,提出了D最小纳什均衡的概念。结合虚拟制造网络中车间调度问题的特点,设计了染色体编码与解码方案以及适应度函数,提出了一种基于遗传算法的博弈调度求解算法来求得该博弈调度模型的D最小纳什均衡。在若干基准实例上验证了该方法的有效性。     

A multi-objective genetic algorithm for scheduling in flow shops to minimize the makespan and total flow time of jobs

In this paper the problem of permutation flow shop scheduling with the objectives of minimizing the makespan and total flow time of jobs is considered. A Pareto-ranking based multi-objective genetic algorithm, called a Pareto genetic algorithm (GA) with an archive of non-dominated solutions subjected to a local search (PGA-ALS) is proposed. The proposed algorithm makes use of the principle of non-dominated sorting, coupled with the use of a metric for crowding distance being used as a secondary criterion. This approach is intended to alleviate the problem of genetic drift in GA methodology. In addition, the proposed genetic algorithm maintains an archive of non-dominated solutions that are being updated and improved through the implementation of local search techniques at the end of every generation. A relative evaluation of the proposed genetic algorithm and the existing best multi-objective algorithms for flow shop scheduling is carried by considering the benchmark flow shop scheduling problems. The non-dominated sets obtained from each of the existing algorithms and the proposed PGA-ALS algorithm are compared, and subsequently combined to obtain a net non-dominated front. It is found that most of the solutions in the net non-dominated front are yielded by the proposed PGA-ALS.     

加工时间不确定的柔性作业车间鲁棒调度方法

针对中小批量环境下加工时间不确定的柔性作业车间调度问题,采用冗余处理方法构建了以最大完工时间为目标的鲁棒调度模型。为降低算法的搜索规模和提高算法的求解速度,提出了顺序搜索机制,并设计两阶段遗传算法,分阶段获取冗余状态和最优结果。采用某柔性生产线的数据进行正交试验,优化了算法关键参数,并构建了柔性生产线仿真模型,对调度结果的鲁棒性和优化目标性能进行了分析。结果表明,该算法在目标性能和鲁棒性上都显著优于标准遗传算法,能有效处理加工时间不确定的柔性作业车间调度问题。     

Product configuration optimization using a multiobjective genetic algorithm

Product configuration is one of the key technologies in the environment of mass customization. Traditional product configuration technology focuses on constraints-based or knowledge-based application, which makes it very difficult to optimize design of product configuration. In this paper, an approach based on multiobjective genetic algorithm is proposed to solve the problem. Firstly, a configuration-oriented product model is discussed. A multiobjective optimization problem of product configuration according to the model is described and its mathematical formulation is designed. Secondly, a multiobjective genetic algorithm is designed for finding near Pareto or Pareto optimal set for the problem. A matrix method used to check constraint is proposed, and the coding and decoding representation of the solution are designed, then a new genetic evaluation and select mechanism is proposed. Finally, performance comparison of the proposed genetic algorithm with three other genetic algorithms is made. The result shows that the proposed genetic algorithm outperforms the other genetic algorithms in this problem.     

基于混合教学优化算法的多车间协作综合调度

目前在处理加工属性类似的多车间协作综合调度问题时，几乎都是采用调度规则，对产品加工工艺结构的依赖度过高，降低了算法对同一类问题不同实例的适应性，并且对大型实例的求解结果普遍欠佳，为此提出了一种混合教学优化算法。该算法在基本教学优化算法的基础上加入采用变异操作模拟的自学习阶段，提高其局部搜索能力，并且在教学、互学和自学三个阶段均按照模拟退火算法中Metropolis准则计算的概率，随机接受学生群体中某一个较差个体作为新个体，进一步提高算法跳出局部最优解的能力；教学、互学和自学三个阶段设计的变换操作均考虑综合调度问题中各虚拟工序之间的顺序约束关系，保证生成的解均是可行解。通过测试以往该类问题实例，得到的结果验证了所提算法的可行性和有效性。     

[工艺规划与装配线平衡]两阶段混合算法求解集成工艺规划与调度问题

提出了求解集成式工艺规划与车间调度问题的两阶段混合算法。在工艺规划阶段,使用遗传算法为每个工件生成可选的近优工艺路线集,动态地为车间调度阶段输入已确定的工艺路线;在车间调度阶段,使用蜜蜂交配优化算法快速寻优,设计了蜂王婚飞的流程以保证算法的全局搜索能力,构建了基于不同邻域结构的工蜂培育幼蜂局部搜索策略。使用基准测试集对提出的方法进行验证,并与现有算法进行对比,计算结果证明了提出方法的有效性。