改进果蝇算法求解混合流水车间调度问题

针对混合流水车间调度问题(HFSP),本文提出了一种新的基于果蝇算法和变邻域搜索的混合优化方法.首先,将关键块内的工序与同阶段其他机器上的工序进行交换,提出了一种基于关键路径的HFSP新邻域结构.其次,针对HFSP的阶段式解码特性,提出了一种邻域解的快速评估方法,并验证了快速评估方法的高效性.然后,基于提出的新邻域结构,并将N7和K-insertion邻域结构引入HFSP,设计了基于上述3种邻域结构的变邻域搜索方法,以此为基础提出了一种针对HFSP的混合优化方法.最后,通过对Carlier和Liao等经典测试集进行测试,验证了所提新邻域结构的可行性和有效性,并将该方法与其他文献的方法进行了对比,验证了所提方法的优越性.     

双目标流水线调度的动态双子群离散果蝇算法

提出了一种基于动态双子群的离散果蝇优化算法,求解以最大完工时间和机床空闲时间的最小化为目标的无等待流水线调度问题。与传统的果蝇算法不同,该算法采用基于工序的编码方式,并用改进的NEH方法进行初始化,提高初始解的质量;根据算法在进化过程中个体的进化水平,动态地将整个群体划分为先进子群和后进子群,简单但有效地插入方法在先进个体邻域内进化精细搜索,贪婪迭代进化机制用于优化后进个体,以此平衡算法的全局开发能力和局部搜索能力;为了提高算法效率,快速算法用于计算函数目标值和判断更新非支配解。仿真试验表明了所提果蝇算法的有效性和高效性。     

新型离散蝙蝠算法求解柔性流水车间调度问题

针对以最小化完工时间为目标的柔性流水车间调度问题,提出了一种新型离散蝙蝠算法。介绍了蝙蝠算法的基本思想,重新定义速度与位置的加法操作来实现粒子的位移,给出了算法的具体实现方案。通过实例仿真和算法比较验证了算法的优化性能,实验结果表明该算法可以有效地求解柔性流水车间调度问题。     

A hybrid variable neighborhood search algorithm for solving the limited-buffer permutation flow shop scheduling problem with the makespan criterion

This paper investigates the limited-buffer permutation flow shop scheduling problem (LBPFSP) with the makespan criterion. A hybrid variable neighborhood search (HVNS) algorithm hybridized with the simulated annealing algorithm is used to solve the problem. A method is also developed to decrease the computational effort needed to implement different types of local search approaches used in the HVNS algorithm. Computational results show the higher efficiency of the HVNS algorithm as compared with the state-of-the-art algorithms. In addition, the HVNS algorithm is competitive with the algorithms proposed in the literature for solving the blocking flow shop scheduling problem (i.e., LBPFSP with zero-capacity buffers), and finds 54 new upper bounds for the Taillard's benchmark instances.     

基于混合果蝇优化算法的现场服务调度问题

员工技能熟练程度对现场服务调度问题（FSSP）的执行效率有极大影响,现有研究中未考虑员工技能因素。针对上述问题,首先以员工的旅行时间、服务时间和等待时间为优化目标,建立考虑员工技能熟练程度的FSSP模型;然后,提出混合果蝇优化算法（HFOA）对该模型进行优化求解,根据问题特征和算法特点,设计了基于矩阵的编码方法;定义了两类矩阵操作,提出了3种搜索算子,重构了果蝇优化算法（FOA）的嗅觉搜索和视觉搜索过程;为了提升算法性能,构造了基于最邻近插入启发式算法的初始化算子;最后,通过典型实例对算法进行了仿真实验,并与遗传算法（GA）、贪婪随机自适应搜索过程（GRASP）算法进行了比较。实验数据显示,与其他两种算法相比,HFOA在均值和最优值方面表现更优秀。结果表明改进初始化方法和搜索策略后,HFOA在优化的精度和稳定性上优于其他算法。     

改进离散粒子群算法求解柔性流水车间调度问题

针对以最小化完工时间为目标的柔性流水车间调度问题(FFSP),提出了一种改进离散粒子群(DPSO)算法.所提算法重新定义粒子速度和位置的相关算子,并引入编码矩阵和解码矩阵来表示工件、机器以及调度之间的关系.为了提高柔性流水车间调度问题求解的改进离散粒子群算法的初始群体质量,通过分析初始机器选择与调度总完工时间的关系,首次提出一种基于NEH算法的最短用时分解策略算法.仿真实验结果表明,该算法在求解柔性流水车间调度问题上有很好的性能,是一种有效的调度算法.     

求解置换流水线调度问题的混合离散果蝇算法

针对置换流水线调度问题,提出了一种新颖的混合离散果蝇算法.算法每一代进化包括4个搜索阶段:嗅觉搜索、视觉搜索、协作进化和退火过程.在嗅觉搜索阶段,采用插入方式生成邻域解;在视觉搜索阶段,选择最优邻域解更新个体;在协作进化阶段,基于果蝇个体间的差分信息产生引导个体;在退火操作阶段,以一定概率接受最优引导个体从而更新种群.同时,通过试验设计方法对算法参数设置进行了分析,并确定了合适的参数组合.最后,通过基于标准测试集的仿真结果和算法比较验证了所提算法的有效性和鲁棒性.     

A palmer-based continuous fuzzy flexible flow-shop scheduling algorithm

 Flexible flow shops can be thought of as generalizations of simple flow shops. In the past, the processing time for each job was usually assumed to be known exactly, but in many real-world applications, processing times may vary dynamically due to human factors or operating faults. In the past, we demonstrated how discrete fuzzy concepts could easily be used in the Palmer algorithm for managing uncertain flexible-flow-shop scheduling. In this paper, we generalize it to continuous fuzzy domains. We use triangular membership functions for flexible flow shops with more than two machine centers to examine processing-time uncertainties and to make scheduling more suitable for real applications. We first use the triangular fuzzy LPT algorithm to allocate jobs, and then use the triangular fuzzy Palmer algorithm to deal with sequencing the tasks. The proposed method thus provides a more flexible way of scheduling jobs than conventional scheduling methods.     

柔性Job shop集成化计划调度模型及其求解算法

考虑不同加工工艺路径的成本因素，从集成化的角度研究了柔性Job shop计划和调度问题，针对问题的结构特点，建立了两层混合整数规划模型，提出门槛接受，遗传算法与启发式规则相结合的混合求解算法，综合考虑各层次决策问题进行求解，实例计算表明，该算法可迅速求得问题的近优解，表现出良好的求解性能。     

The economic lot scheduling problem: A pure genetic search approach

The economic lot scheduling problem (ELSP) is the challenge of accommodating several products to be produced on a single machine in a cyclical pattern. A solution involves determining the repetitive production schedule for N$N$ products with a goal of minimizing the total of setup and holding costs. We develop the genetic lot scheduling (GLS) procedure. This method combines an extended solution structure with a new item scheduling approach, allowing a greater number of potential schedules to be considered while being the first to explicitly state the assignment of products to periods as part of the solution structure. We maintain efficient solution feasibility determination, a problematic part of ELSP solution generation and a weakness of several other methods, by employing simple but effective sequencing rules that create “nested” schedules. We create a binary chromosomal representation of the new problem formulation and utilize a genetic algorithm to efficiently search for low cost ELSP solutions. The procedure is applied to a benchmark problem suite from the literature, including Bomberger's stamping problem [Bomberger, A dynamic programming approach to a lot scheduling problem. Management Science 1966; 12:778–84], a problem that has been under investigation since the mid 1960's. The genetic lot scheduling procedure produces impressive results, including the best solutions obtained to date on some problems.     

Energy-efficient scheduling for a flexible flow shop using an improved genetic-simulated annealing algorithm

The traditional production scheduling problem considers performance indicators such as processing time, cost, and quality as optimization objectives in manufacturing systems; however, it does not take energy consumption or environmental impacts completely into account. Therefore, this paper proposes an energy-efficient model for flexible flow shop scheduling (FFS). First, a mathematical model for a FFS problem, which is based on an energy-efficient mechanism, is described to solve multi-objective optimization. Since FFS is well known as a NP-hard problem, an improved, genetic-simulated annealing algorithm is adopted to make a significant trade-off between the makespan and the total energy consumption to implement a feasible scheduling. Finally, a case study of a production scheduling problem for a metalworking workshop in a plant is simulated. The experimental results show that the relationship between the makespan and the energy consumption may be apparently conflicting. In addition, an energy-saving decision is performed in a feasible scheduling. Using the decision method, there could be significant potential for minimizing energy consumption.     

最优子种群遗传算法求解柔性流水车间调度问题

为了验证最优子种群遗传算法在解决柔性流水车间调度问题时相比于传统遗传算法的优越性,分析了柔性流水车间调度问题的特点,并运用一种新的编码方法和新的遗传算法求解了该问题。考虑到最优个体保护策略法对复杂问题容易使种群收敛陷入局部最优解,为了提高精度、加快较优个体的产生并避免陷入局部最优解,首先提出了一种合理、全面的编码方法,并运用最优子种群遗传算法来求解柔性流水车间调度问题。最后运用实例验证了最优子种群遗传算法的有效性、优越性和编码方式的合理性。     

Hybrid monkey search algorithm for flow shop scheduling problem under makespan and total flow time

This paper addresses a sub-population based hybrid monkey search algorithm to solve the flow shop scheduling problem which has been proved to be non-deterministic polynomial time hard (NP-hard) type combinatorial optimization problems. Minimization of makespan and total flow time are the objective functions considered. In the proposed algorithm, two different sub-populations for the two objectives are generated and different dispatching rules are used to improve the solution quality. To the best of our knowledge, this is the first application of monkey search algorithm to solve the flow shop scheduling problems. The performance of the proposed algorithm has been tested with the benchmark problems addressed in the literature. Computational results reveal that the proposed algorithm outperforms many other heuristics and meta-heuristics addressed in the literature.     

基于改进离散和声算法的批量流水线调度研究

针对批量流水线调度问题,提出了以总流经时间为目标的改进离散和声算法。与基本的和声算法相比,该算法首先采用了基于工件序列的编码方式,使其直接应用于调度问题,同时运用NEH和SWAP方法产生初始和声库,保证了初始种群具有较高的质量和多样性。使用自适应和声微调概率参数和INSERT方法产生新解,提高了算法的优化性能。为了提高算法的局部搜索能力,结合交换扰动策略和插入邻域搜索算法给出了两种混合求解策略。仿真实验表明所提算法的有效性。     

解决具有混合约束柔性流水车间调度问题的粒子群优化算法

针对既存在阻塞限制工件又存在无等待约束工件的柔性流水车间调度问题, 提出了一种离散粒子群优化的求解方法。该方法采用基于排列的编码形式, 设计了推进—迭代算法进行解码并计算问题目标值, 利用离散粒子群优化算法进行全局优化, 利用迭代贪婪(iterated greedy, IG)算法提高种群个体的局部搜索能力。此外, 根据问题特点, 提出最早释放优先(first release first, FRF)和最早完工优先(first complete first, FCF)两种机器分配策略。仿真结果表明, 所提出的方法求解混合约束下柔性流水车间调度问题是可行的、有效的。     

A hybrid discrete differential evolution algorithm for the no-idle permutation flow shop scheduling problem with makespan criterion

This paper presents a hybrid discrete differential evolution (HDDE) algorithm for the no-idle permutation flow shop scheduling problem with makespan criterion, which is not so well studied. The no-idle condition requires that each machine must process jobs without any interruption from the start of processing the first job to the completion of processing the last job. A novel speed-up method based on network representation is proposed to evaluate the whole insert neighborhood of a job permutation and employed in HDDE, and moreover, an insert neighborhood local search is modified effectively in HDDE to balance global exploration and local exploitation. Experimental results and a thorough statistical analysis show that HDDE is superior to the existing state-of-the-art algorithms by a significant margin.     

Optimizing distributed no-wait flow shop scheduling problem with setup times and maintenance operations via iterated greedy algorithm

Nowadays, distributed scheduling problem is a reality in many companies. Over the last years, an increasingly attention has been given to the distributed flow shop scheduling problem and the addition of constraints to the problem. This article introduces the distributed no-wait flow shop scheduling problem with sequence-dependent setup times and maintenance operations to minimize makespan. A mixed-integer linear programming (MILP) is to mathematically describe the problem and heuristic procedures to incorporate maintenance operations to job scheduling are proposed. An Iterated Greedy with Variable Search Neighborhood (VNS), named IG_NM, is proposed to solve small and large instances with size of 4,800 and 13,200 problems, respectively. Computational experiments were conducted to evaluate the performance of IG_NM in comparison with MILP and the most recent methods of literature of distributed flow shop scheduling problems. Statistical results show that in the trade-off between effectiveness and efficiency the proposed IG_NM outperformed other metaheuristics of the literature.     

基于改进蝙蝠算法的柔性流水车间排产优化问题研究

为解决柔性流水车间调度问题( flexible flow shop scheduling problem,FFSP),提出了一种基于精英个体集的自适应蝙蝠算法(self-adaptive elite bat algorithm,SEBA)。针对蝙蝠算法存在求解离散问题具有局限性、易陷入局部极值、优化结果精度低等问题,该算法采用ROV(ranked order value)编码方式,使算法适用于求解离散型的FFSP问题;提出基于汉明距离的精英个体集,由多个适应度高但相似度低的精英个体轮流引导种群进化,增强种群进化活力,避免寻优过程陷入局部极值;提出自适应位置更新机制,提高算法优化精度。最后采用不同规模的标准实例对改进算法进行测试,与已有算法进行对比,实验结果验证了改进蝙蝠算法求解FFSP问题的有效性。     

A neural network model and algorithm for the hybrid flow shop scheduling problem in a dynamic environment

A hybrid flow shop (HFS) is a generalized flow shop with multiple machines in some stages. HFS is fairly common in flexible manufacturing and in process industry. Because manufacturing systems often operate in a stochastic and dynamic environment, dynamic hybrid flow shop scheduling is frequently encountered in practice. This paper proposes a neural network model and algorithm to solve the dynamic hybrid flow shop scheduling problem. In order to obtain training examples for the neural network, we first study, through simulation, the performance of some dispatching rules that have demonstrated effectiveness in the previous related research. The results are then transformed into training examples. The training process is optimized by the delta-bar-delta (DBD) method that can speed up training convergence. The most commonly used dispatching rules are used as benchmarks. Simulation results show that the performance of the neural network approach is much better than that of the traditional dispatching rules.This revised version was published in June 2005 with corrected page numbers.