面向订单的混流装配线多目标调度研究

针对面向订单的混流装配线车间组装过程中出现堆叠的问题,对该类生产线特点进行了分析,提出了一种理论调度优化模型及其算法.建立了以车间交货时间的准时度和组件完工的同时度为目标函数的车间多目标调度优化模型;对粒子群算法进行了改进,设计了基于吸引子与自然选择的社会粒子群算法来求解多目标优化模型;研究了粒子群的信息描述方法,提出...     

混流生产车间设施布局方法概述

提出两种布局设计的思路：第一种思路是将混流生产线看成典型的流水线,运用设计流水线布局的方法,又考虑到混流生产的特点,形成了混流生产车闰布局的一般步骤。第二种恩路是将混流车间设施布局看成二次分配问题,应用现代智能优化算法对车间布局进行优化设计。     

面向云制造的混流混合车间调度问题

为解决云制造环境下混流混合车间的生产调度优化问题,综合考虑混流装配与零部件加工的集成优化以及外协云任务与自制任务的协同调度,建立了以最小化最大完工时间、均衡化零部件生产和最大化零件车间机器利用率为优化指标的多目标车间调度模型。基于零件分批和车间调度的两阶段求解策略,设计了一种两级递阶结构的混合生物地理学优化算法,采用在迁移算子中嵌入差分进化算法的变异策略来提高算法的搜索效率。最后,通过实例验证了模型和算法的有效性。     

基于排队网模型的柔性流水车间缓冲区容量优化

针对订货型单类型工件柔性流水车间缓冲区容量优化设置问题,在考虑各级工序节点之间耦合关系的前提下,基于连续时间马尔可夫随机过程原理建立了多级柔性流水车间的排队网节点状态模型。在给出系统产出率为目标和平均生产周期条件约束的情形下,利用该模型计算系统的关键性能指标,提出一种针对柔性流水车间特点的缓冲区容量优化分支定界算法。通过该算法计算算例并与Em-plant工具仿真结果进行对比分析,最终确定了合理的柔性流水车间缓冲区容量。     

多级车间生产计划和调度的集成优化

针对一类多级制造系统建立了生产计划和调度的集成优化模型。该多级制造系统为三种类型车间的一个串联,主要有作业车间、并行生产车间和流水车间,且终端产品和上游车间制造的零部件之间为装配关系,因此生产关系十分复杂。在分析批量生产特点的基础上给出了一个批量动态分割合并算法,并构造了一个基于遗传进化的启发式算法对该模型进行求解。与递阶分解方法的比较试验表明所提出的集成优化方法是有效的。     

基于瓶颈工序的多资源多目标机械加工车间调度研究

为求解多资源约束的机械加工车间调度问题,建立了包括最大完工时间、平均流经时间、总拖期惩罚和生产成本在内的多目标优化模型,并结合免疫遗传算法和约束理论提出了一种基于瓶颈工序的机械加工车间调度算法。算法依据约束理论提出了一种基于工序的多参数级联编码方法和基于鼓-缓冲器-绳索(DBR)的四阶段解码方法,以及有效的交叉、变异操作。基于瓶颈工序的免疫操作及基于浓度的选择更新机制,保证了多目标优化问题的收敛性以及Pareto解集的多样性。仿真结果表明了该算法的可行性和有效性。     

基于混合遗传算法的混流混合车间协同调度问题

为解决一类具有多品种混流生产特征和作业车间与流水车间集成的混流混合车间协同调度问题,给出了以在制品成本最小为目标的混流混合车间调度问题模型;采用零件加工、部件装配、产品总装的三段协同编码方法,给出了一种集成模拟退火算法的混合遗传算法,并在模拟退火算法中引入变温度参数来平衡算法效率。最后,通过某冰箱混流装配企业典型实例验证了模型和算法的有效性。     

基于时间窗约束的车间物料配送路径优化方法

针对混流生产车间物料配送需求的准确性和及时性,综合考虑实时生产状态和不确定因素,以实时生产数据为依据,动态计算各工位配送时间窗,并用正态模糊数的隶属度表示工位满意度。在此基础上,建立以配送成本最低为目标,以时间窗、运载能力和持续能力为约束的物料配送路径优化模型。采用基于禁忌搜索的改进遗传算法求解模型,该算法将禁忌搜索的记忆功能融入遗传算法中,防止遗传算法陷入局部最优。最后,通过实例验证该方法的有效性和可行性。     

基于敏捷制造单元的车间动态重构

为适应现代车间的敏捷化需求,提出了一种基于敏捷制造单元的车间动态重构方法.车间的动态重构是一个优化制造资源,进而构造面向产品的敏捷制造单元,形成虚拟车间的过程,采用数学规划和模糊理论相结合的方法,优化制造资源.同时,提出了一种基于不完全知识和进化博弈理论的动态单元重构模型,它能够面向不确定的需求目标,采用自下而上和自上而下相结合的方法,快速生成稳定优化的可重构制造单元,从而实现敏捷车间的组织再设计.该模型求解采用协同进化算法,并通过实例,验证了该方法的可行性和有效性.     

基于约束理论的混合复杂流水线规划调度算法

针对可重入、批处理、准备时间长以及多目标混合流水生产线问题,给出了复杂生产线的一般描述,提出了一种基于约束理论的规划调度算法。整个算法框架建立在约束理论五步原则基础上,并通过目标规划的思想实现了多目标优化,为了验证算法解决复杂性的能力,通过估算瓶颈能力给出了生产线的上界以作比较。     

Sequencing the mixed-model assembly line to minimize the total utility and idle costs with variable launching interval

A mixed-model assembly line (MMAL) is a type of a production line where a variety of products is assembled on it. A mixed-model assembly line problem involves not only solving the traditional problems of the assembly line design (i.e., determining the cycle time, the number and sequence of stations, and the balancing problem) but also determining the sequence of products in assembly line. The product sequencing has a high effect on the mixed-model assembly line efficiency. In this paper, we consider sequencing problem with a variable launching interval between products on the assembly line. A mathematical model is presented, which is capable to solve the small-sized ones of these problems. The considered problem involves two optimization problems (the sequencing problem and launching interval problem). Since this problem is strongly NP-hard, a hybrid metaheuristic algorithm based on the simulated annealing approach and a heuristic approach is developed. The heuristic approach (launching interval between products algorithm) is presented to solve the launching interval problem for each sequence. Numerical experiments are used to evaluate the performance and effectiveness of the proposed algorithm. Variable launching interval consideration in MMAL problem causes the higher complexity of this problem. However, this assumption improves the considered goals for this problem. Not only a power algorithm for MMAL is presented in this paper but also the effect of this assumption is discussed. Numerical experiments are used to evaluate the performance and effectiveness of the proposed algorithm.     

多目标柔性作业车间调度决策精选机制研究

针对多目标柔性作业车间调度优化无法找到唯一最优解的问题，提出多目标遗传算法和层次分析法模糊综合评判的分阶段优化策略。提出优化阶段和精选阶段的优化任务，优化阶段选出一组Pareto解集，精选阶段从Pareto解集中选出最优解；在精选阶段运用层次分析法和模糊评判集成的策略精选调度决策。决策算例证明提出的方法是可行的，可很好地帮助决策者选择出一个最满意的解。     

基于遗传-粒子群混合算法的柔性作业车间多资源调度问题

在传统柔性作业车间调度问题(FJSP)中加入运输和装配环节,提出一种柔性作业车间多资源调度问题(MRFJSP),以完工时间最短为目标建立了包含加工、运输和装配的柔性作业车间调度模型。为了提高传统遗传算法(GA)在车间调度问题中的寻优能力,将粒子群算法(PSO)的寻优过程进行改进并与遗传算法进行结合,提出一种带保优策略的遗传-粒子群混合算法,利用单层编码对模型进行求解。通过算例验证了模型的可行性,并将提出的混合算法与遗传算法和粒子群算法进行比较,证明了混合算法的优越性。     

柔性流水车间设备利用率排产优化问题研究

针对具有工序约束信息的柔性流水车间的设备利用率优化问题,提出利用PSODE混合算法来解决该问题,全局优化过程采用群体优化算法,在局部优化过程中通过上下道关联工序约束信息来控制工件的分配,将并行工位总设备利用率作为适应度函数,构建了具有关联工序约束的柔性流水车间生产调度模型,确定生产工件的加工路径、加工顺序、开工时间和完工时间。通过多组方案数值计算结果对比分析,验证了PSODE算法解决柔性流水车间设备利用率优化问题的有效性。     

Flexible job shop scheduling with tabu search algorithms

This paper presents a tabu search algorithm that solves the flexible job shop scheduling problem to minimize the makespan time. As a context for solving sequencing and scheduling problems, the flexible job shop model is highly complicated. Alternative operation sequences and sequence-dependent setups are two important factors that frequently appear in various manufacturing environments and in project scheduling. In this paper, we present a model for a flexible job shop scheduling problem while considering those factors simultaneously. The purpose of this paper is to minimize the makespan time and to find the best sequence of operations and the best choice of machine alternatives, simultaneously. The proposed tabu search algorithm is composed of two parts: a procedure that searches for the best sequence of job operations, and a procedure that finds the best choice of machine alternatives. Randomly generated test problems are used to evaluate the performance of the proposed algorithm. Results of the algorithm are compared with the optimal solution using a mathematical model solved by the traditional optimization technique (the branch and bound method). After modeling the scheduling problem, the model is verified and validated. Then the computational results are presented. Computational results indicate that the proposed algorithm can produce optimal solutions in a short computational time for small and medium sized problems. Moreover, it can be applied easily in real factory conditions and for large size problems. The proposed algorithm should thus be useful to both practitioners and researchers.     

Sequencing mixed-model assembly lines by considering feeding lines

A mixed-model assembly line is a type of production line where different models of a product are assembled on. Mixed-model assembly lines can respond to unanticipated changes in product demands quickly without keeping so many inventories. Designing mixed-model assembly line involves solving the traditional problems of the assembly line design (consists of balancing problem, determining cycle time, and the number and sequence of stations) in addition of determining the sequence of products in assembly line. The main goal of this paper is presenting a method in order to determine the sequence of products in mixed-model assembly line by considering Just-in-Time systems. Moreover, supplying some required components from feeding lines is considered. A mathematical model is presented which is capable of specifying the sequence of products in the mixed-model assembly line by considering main criteria and keeping feeding lines balanced. Mathematical model can be used for solving small-size problems. Because the combinatorial nature of sequencing problems typically provides an intractable search space for problems of “real world” size, the search heuristics of simulated annealing and ant colony algorithms are presented and used to find solutions for several problem sets. Experimentations show that the simulated annealing approach outperforms the ant colony approach in objective function performance.     

基于混合粒子群算法具有交货期瓶颈的作业车间调度问题

为了解决一类具有交货期瓶颈的作业车间调度问题,给出了基于订单优势的交货期满意度和交货期瓶颈资源确定方法,以工件拖期加权和最小为优化目标,建立了基于交货期满意度和瓶颈资源约束的作业车间调度模型;为了求解该调度模型,设计了一种基于模拟退火的混合粒子群算法,该算法采用随机工序表达方式进行编码,并在模拟退火算法中引入变温度参数来提高算法效率。通过随机仿真,分别采用PSO-SA、SA和PSO对所建立的调度模型进行求解,结果显示PSO-SA算法的广泛性好、求解效率高且算法的稳定性好,验证了模型和算法的有效性。