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《计算机集成制造系统》2017,(10)
为解决在确定的子任务加工顺序条件下进行服务组合时,云服务组合的灵活性降低、解空间被限制等问题,提出了用于描述加工顺序的工艺逻辑矩阵,建立了基于双层蚁群算法的,以时间最短、成本最低、能耗最少、可靠性最高为目标的服务组合优选模型。针对加工顺序与任务工艺逻辑要求不一致的情况,在算法中加入了基于工艺逻辑的加工顺序交换机制。通过仿真实验验证了该算法的有效性,并研究了在不同物流条件和工艺逻辑要求下,算法收敛速度的变化规律。 相似文献
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针对岸桥故障等原因引起的码头调度方案重新调整的实际问题,对邻近船舶采用岸桥共享作业的方法,以船舶作业时间最短和码头作业成本最低为目标建立多目标优化模型,利用混合式多点交叉和混合式单点变异方式改进NSGA-Ⅱ算法,并融入岸桥共享原则的邻域搜索策略。为寻找满足决策者偏好的调度方案,在兼顾船公司和港口方利益基础上,利用Pareto前沿分布信息,采用Pareto非劣解相对于各优化目标的偏向量化方法,得到了适合决策者偏好的最终方案。最后,以我国某集装箱码头为例验证了所提模型和算法的可行性;通过算法对比,显示改进后的算法更为有效。该研究成果可为提高港口管理水平提供决策依据。 相似文献
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平行机调度问题在工业界有着广泛应用,实际生产中瓶颈工序的调度很多属于这类问题.运用增强学习算法来研究以最小化作业的加权平均滞留时间为目标的动态平行机调度问题Qm I rj,sjk,Mj I ∑wjfj,考虑与作业顺序相关的转换时间和机器-作业资格约束.为了把调度问题转化为增强学习问题,定义了系统状态的表示方式,利用加权最短加工时间优先(WSPT)规则、Weng算法、排名(RA)算法和LFJ-RA(Least Flexible Job-Ranking Algorithm)算法构造行为,定义了与调度目标函数等价的报酬函数,并采用结合函数泛化器的Q学习算法来解决.实验表明Q学习算法对每个测试问题的调度结果都优于WSPT规则、排名算法、LFJ-RA算法和Weng算法. 相似文献
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对混流装配投产顺序的不同调度目标进行分析,建立混流装配投产的目标函数,着重讨论了模拟退火算法的原理及在混流装配投产中的应用流程,最后通过实例对算法进行验证.验证结果表明,模拟退火算法比常规的目标追迹法更有效,可以在生产中推广应用. 相似文献
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《机械制造与自动化》2016,(6):92-95
激光切割机的路径优化问题是激光切割行业的一个关键问题,针对其特点将其归纳为广义旅行商问题,利用改进的遗传蚁群算法来求解该问题。算法以时间距离最短为目标函数,对轮廓切割顺序及轮廓切割起始点同时进行优化。为了让算法所得解能够快速聚集在最优解附近而又不至于陷入局部最优解,利用遗传算法快速随机的全局搜索能力来产生蚁群算法初期的信息素分布,蚁群算法采用最大最小蚂蚁算法同时在其加入变异因子。仿真结果表明取得了非常好的效果。 相似文献
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以陶瓷行业车间生产计划为背景,将其抽象为调整时间与顺序相关的能耗优化调度问题进行研究。以最少化总能耗为目标,建立数学模型;提出了基于NEH算法的混合遗传算法,其中初始化种群中,定义了虚拟工件概念,采用了改进NEH规则对种群初始化;为了对上述算法进行验证,提出了该问题的两个下界,设计了仿真试验,进行下界背离程度分析和CPU运行时间分析。计算结果表明:所设计的混合遗传算法能够在可接受的计算时间内获得合理的解。 相似文献
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Masoud Rabbani Farzad Radmehr Neda Manavizadeh 《The International Journal of Advanced Manufacturing Technology》2011,54(5-8):775-788
Mixed-model production is the practice of assembling different and distinct models in a line without changeovers with responding to sudden demand changes for a variety of models. In this paper, we specify sequence of models to minimize conveyer stoppages. We assume that our lines are fixed and we cannot change the balance of the lines. When the condition of lines like setup cost and demand of each model change, it is important to specify the sequence for minimizing the conveyer stoppages without balancing the line again because the main lines are fixed. We consider three objective functions simultaneously: minimizing the variation in the actual and required production capacity of the line and minimizing the objectives which increase the chance of conveyer stoppage, including: (a) minimizing the total setup time, (b) minimizing the total production variation cost, and (c) minimizing the total utility work cost. Because of conflicting objectives, we propose the fuzzy goal programming-based approach to solve the model. Finally, we present an estimator for nearness of conveyer stoppages and study about affecting of sub-lines and changing the conveyer velocity in a station for reducing stoppages. 相似文献
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Sejung Kim Young Hoon Lee Taeyong Yang Namkyu Park 《The International Journal of Advanced Manufacturing Technology》2008,39(3-4):333-343
This paper discusses the problem of determining workload in a semiconductor fabrication line for providing robust production control. A mathematical model is proposed to determine the amount of wafers to be processed on equipment in a photolithography process where the setup time is incurred if the type of wafers is changed on the equipment. The objective of the model is to control the fabrication line by maintaining the target work-in-process (WIP) level as close as possible for the purpose of short cycle time and by minimizing the setup time loss for maximal throughput. The proposed model is formulated using mixed integer programming (MIP) to minimize the weighted sum of two objective functions. A heuristic approach is suggested using linear relaxation and its adjustment. Performances are evaluated for the optimal solution with computational cost and for the heuristics. It is shown that the heuristics give good solutions which are 10% away, on average, from the optimal solution, but which can be obtained in a few seconds. 相似文献
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Taeho Park Taehyung Lee Chang Ouk Kim 《The International Journal of Advanced Manufacturing Technology》2012,59(1-4):325-333
This paper addresses job scheduling problems with parallel machines. To satisfy customers better in a manufacturing company, meeting due dates has been an important performance metric. Besides the numerous other factors affecting due date satisfaction, the splitting of a job through parallel machines can contribute to the reduction of production lead time, resulting in less job tardiness against their due dates. Thus, this paper presents heuristic algorithms for minimizing total tardiness of jobs to meet their due dates in a manufacturing shop with identically functioning machines. The algorithms take into account job splitting and sequence-dependent major/minor setup times. The performance of the proposed heuristics is compared with that of past three algorithms in the literature. 相似文献
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ACO-based multi-objective scheduling of parallel batch processing machines with advanced process control constraints 总被引:1,自引:1,他引:0
Li Li F. Qiao Q. D. Wu 《The International Journal of Advanced Manufacturing Technology》2009,44(9-10):985-994
This research was motivated by a scheduling problem in the dry strip operations of a semiconductor wafer fabrication facility. The machines were modeled as parallel batch processing machines with incompatible job families and dynamic job arrivals, and constraints on the sequence-dependent setup time and the qual-run requirements of advanced process control. The optimization had multiple objectives, the total weighted tardiness (TWT) and makespan, to consider simultaneously. Since the problem is NP-hard, we used an Ant Colony Optimization (ACO) algorithm to achieve a satisfactory solution in a reasonable computation time. A variety of simulation experiments were run to choose ACO parameter values and to demonstrate the performance of the proposed method. The simulation results showed that the proposed ACO algorithm is superior to the common Apparent Tardiness Cost-Batched Apparent Tardiness Cost rule for minimizing the TWT and makespan. The arrival time distribution and the number of jobs strongly affected the ACO algorithm’s performance. 相似文献
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Rubén Ruiz Ali Allahverdi 《The International Journal of Advanced Manufacturing Technology》2007,35(5-6):551-565
This paper considers the m-machine no-wait flowshop problem with the objective of minimizing the maximum lateness where setup times are considered as
separate from processing times and treated as sequence-independent. A dominance relation is developed for the case of three
machines and several heuristics and four new effective and efficient genetic algorithms are proposed. The genetic algorithms
make use of advanced concepts like steady-state and elitist generational scheme as well as new fast-selection operators. Extensive
experimentation is conducted to evaluate the performance of the dominance rule, the proposed heuristics, and the genetic algorithms.
The computational and statistical analyses by means of experimental designs show that the genetic algorithms provide better
results than the existing literature under the same conditions. Additionally, the proposed dominance rule shows great potential
for instances where the processing and setup times are tightly distributed. 相似文献
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Ravindra Gokhale M. Mathirajan 《The International Journal of Advanced Manufacturing Technology》2012,60(9-12):1099-1110
In this paper, we address a scheduling problem for minimizing total weighted flowtime, observed in automobile gear manufacturing. Specifically, the bottleneck operation of the pre-heat treatment stage of gear manufacturing process has been dealt with in scheduling. Many real-life scenarios like unequal release times, sequence dependent setup times, and machine eligibility restrictions have been considered. A mathematical model taking into account dynamic starting conditions has been proposed. The problem is derived to be NP-hard. To approach the problem, a few heuristic algorithms have been proposed. Based on planned computational experiments, the performance of the proposed heuristic algorithms is evaluated: (a) in comparison with optimal solution for small-size problem instances and (b) in comparison with the estimated optimal solution for large-size problem instances. Extensive computational analyses reveal that the proposed heuristic algorithms are capable of consistently yielding near-statistically estimated optimal solutions in a reasonable computational time. 相似文献
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EDWARD M Knod 《机械工程学报(英文版)》2006,19(4):487-491
Firstly an overview of the potential impact on work-in-process (WIP) and lead time is provided when transfer lot sizes are undifferentiated from processing lot sizes. Simple performance examples are compared to those from a shop with one-piece transfer lots. Next, a mathematical programming model for minimizing lead time in the mixed-model job shop is presented, in which one-piece transfer lots are used. Key factors affecting lead time are found by analyzing the sum of the longest setup time of individual items among the shared processes (SLST) and the longest processing time of individual items among processes (LPT). And lead time can be minimized by cutting down the SLST and LPT. Reduction of the SLST is described as a traveling salesman problem (TSP), and the minimum of the SLST is solved through job shop scheduling. Removing the bottleneck and leveling the production line optimize the LPT. If the number of items produced is small, the routings are relatively short, and items and facilities are changed infrequently, the optimal schedule will remain valid. Finally a brief example serves to illustrate the method. 相似文献