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1.
提出一类资源可协作的柔性生产调度问题,利用包含过程流子网和资源子网的赋时Petri网对该问题建模。采用两级遗传递阶优化方法来求解资源可协作的柔性生产调度问题,在自适应遗传算法优化加工路径的基础上,再用单亲遗传算法优化作业排序,并通过运行Petri网仿真来获得调度性能评价。最后的实例仿真结果说明了算法的有效性。  相似文献   

2.
针对绿色制造模式的作业车间调度中,不但要缩短生产周期和降低生产成本,而且要减少资源消耗和对环境的负面影响这一问题,建立包含加工时间、生产成本、资源消耗和环境影响等信息的Petri网模型。通过为机器分配工序来消解因机器库所共享引起的冲突,得到表示调度方案的标识图。提出生成可行调度标识图的三种方 法,并采用多目标遗传算法和多目标模拟退火算法相结合的混合算法对其优化。仿真结果表明算法的可行性和有效性。  相似文献   

3.
基于遗传算法的多资源作业车间智能优化调度   总被引:3,自引:0,他引:3  
提出一种基于遗传算法的调度算法,用于解决作业车间的加工受到机床、操作工人和机器人等多种生产资源制约条件下的优化调度。以生产周期为目标进行的优化调度,将遗传算法和分派规则相结合,通过交叉、交异等遗传操作,得到目标的最优或次优解。最后对算法进行了仿真研究,并给出了算法运行结果,仿真结果表明该算法是可行的。  相似文献   

4.
自动化制造最小完工时间调度是一个典型的组合优化问题。本文提出一种模拟退火遗传算法,应用于自动化制造最小完工时间调度优化。以最小化时间为目标代价函数,通过遗传算法的复制、选择和变异操作来实现大范围的全局搜索,通过仿真退火算法的逐步降温实现小范围的局部搜索,并行实现方案加速了其求解的速度。与模拟退火算法和遗传算法相比:该算法在解的质量、收敛速度和运行时间上均具有一定的优势。  相似文献   

5.
为解决柔性装配系统的设备调度问题,提出了一种将基于延时Petri网的装配过程仿真与基于遗传算法相结合的调度方法。在该方法中,遗传算法使用的染色体是由延时Petri网模型中的部分选择库所名称排列而成,每个染色体都代表一种设备调度方案。遗传操作包括选择、交叉和变异3种类型,利用基于延时Petri网的装配过程模型进行仿真,得到每个染色体相对应的装配时间,进而将装配时间通过适应度函数转化为适应度。该方法融合了Petri网和遗传算法各自的优点,较好地解决了柔性装配系统中的装配建模和装配任务分配优化的问题。仿真实验证明该方法是有效的。  相似文献   

6.
应用模拟退火算法优化遗传算法实现了露天矿卡车的实时优化调度。首先,针对所建卡车调度模型的单目标、多约束、非线性优化的特点,应用求解此类问题表现优越的遗传算法进行求解。其次,针对遗传算法局部搜索能力不足的特点,应用局部搜素能力强的模拟退火算法对其进行优化并详细阐述了模拟退火算法优化遗传算法的基本思想和算法流程。接着,应用典型的TSP问题对模拟退火优化遗传算法进行了验证。最终,应用Mtlab编程软件编制了基于SA-GA算法的露天矿卡车调度程序,并以实际生产数据进行了实验验证。  相似文献   

7.
针对服装生产流水线调度问题,以最小化最大流程时间为目标,将具有全局优化特点遗传算法应用于服装生产流水线调度中.算法采用基于工序的编码方式和具有简单操作的单亲遗传算子,并在调度实例应用中取得满意的效果.仿真结果表明:该算法优化了调度方案,缩减了最小化完工时间,能够有效、高质量地解决服装生产流水线调度问题.  相似文献   

8.
天车作为重型机械加工车间主要的物料搬运设备,其调度方法直接影响生产的连续性和生产效率。重型机械加工车间天车调度是典型的多机多任务问题,以完成生产任务为目标建立基于免疫遗传算法的仿真模型和天车调度优化方法。该模型结合过程仿真与启发式算法有效解决天车调度过程中由于空间约束导致的多机多任务冲突,通过免疫算法的免疫机理对各近似最优解进行动态邻域搜索,维持了群体多样性,实现了多峰值收敛,使调度方案有效可行。最后通过实例仿真验证了该天车调度优化方法的可行性和有效性。  相似文献   

9.
车间生产调度问题(Job-shop scheduling problem,JSSP)属于NP完全问题,现在多使用现代优化算法来解决此类问题.本文将模拟退火算法、禁忌搜索算法的思想融入到遗传算法中,提出了模拟退火-交叉机制和禁忌搜索-变异机制,形成了一种适用于解决车间调度方面问题的新的混合遗传算法.三种算法取长补短,使得遗传算法局部搜索能力差和易早熟的缺点得以改善.同时运用这种混合遗传算法对经典车间调度问题进行了仿真.  相似文献   

10.
基于仿真的多机流水车间成组作业调度   总被引:1,自引:0,他引:1  
邹先军  金烨 《机械制造》2005,43(11):68-71
以总流程时间为优化目标,首先对多机流水车间成组作业调度的最小化总流程时间问题进行了数学建模,然后以三机调度为例在eM-Plant(仿真软件)环境里对该问题进行仿真建模,最后在eM-Plant环境里将仿真模型与遗传算法结合起来对这一类实例进行求解;结果表明这是一种实际有效的方法.  相似文献   

11.
采用赋时变迁Petri网,建立了一种作业车间调度模型.通过为机器分配工序来消解因机器库所共享而引起的冲突,得到了表示调度方案的标志图,给出了一种生成可行调度标志图的方法.同时,提出了一种变迁激发序列编码的离散版粒子群算法,并将模拟退火算法嵌入到该粒子群算法中,以提高算法的优化性能.仿真结果验证了混合算法的可行性和有效性.  相似文献   

12.
基于Petri网和模拟退火遗传算法的并行测试研究   总被引:2,自引:2,他引:2  
马敏  陈光 《仪器仪表学报》2007,28(2):331-336
针对自动测试系统中并行测试任务调度复杂、难以优化的问题,提出了一种Petri网技术和模拟退火遗传算法相结合的任务调度优化算法。首先为并行测试系统建立时间Petri网模型,然后将激发的变迁序列集作为并行测试任务调度路径。为了得到最优路径,引入模拟退火遗传(GASA)算法进行搜索。在搜索过程中,将能激发的变迁序列作为染色体,进行选择、交叉和变异。为了防止算法出现收敛过早,陷入局部最优解的现象,还要对个体进行模拟退火操作,最后得到测试完成时间最短的任务调度序列。  相似文献   

13.
建立了以最大总完成时间最小为目标的混合车间调度模型。该模型包括作业车间和并行流水装配车间两部分调度问题。为降低问题求解难度,采用分解的策略对调度问题分阶段求解,并引入多Agent协商机制和模拟退火算法与免疫遗传算法相结合,提出了基于分解策略的免疫遗传算法,并通过在某汽车减振器企业的实施验证了模型和算法的有效性。  相似文献   

14.
Job shop scheduling (JSS) problems consist of a set of machines and a collection of jobs to be scheduled. Each job consists of several operations with a specified processing order. In this paper, a job shop model problem is scheduled with the help of the Giffler and Thompson algorithm using a priority dispatching rule (PDR). A conflict based PDR is used to schedule the job shop model by using Genetic Algorithms (GAs). An iterative method is applied to the job model to find the optimal conflict-based PDR order and the operation sequence. The same job shop model is also scheduled based on an operation using simulated annealing (SA) and hybrid simulated annealing (HSA). A makespan of the job model is used as an objective. These four methods are considered as different solutions for each problem. A two-way analysis of variance (ANOVA) is applied to test its significance.  相似文献   

15.
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.  相似文献   

16.
This paper considers group scheduling problem in hybrid flexible flow shop with sequence-dependent setup times to minimize makespan. Group scheduling problem consists of two levels, namely scheduling of groups and jobs within each group. In order to solve problems with this context, two new metaheuristics based on simulated annealing (SA) and genetic algorithm (GA) are developed. A design procedure is developed to specify and adjust significant parameters for SA- and GA-based metaheuristics. The proposed procedure is based on the response surface methodology and two types of objective function are considered to develop multiple-objective decision making model. For comparing metaheuristics, makespan and elapsed time to obtain it are considered as two response variables representing effectiveness and efficiency of algorithms. Based on obtained results in the aspect of makespan, GA-based metaheuristic is recommended for solving group scheduling problems in hybrid flexible flow shop in all sizes and for elapsed time SA-based metaheuristic has better results.  相似文献   

17.
JIT柔性混合流水车间生产调度问题研究   总被引:1,自引:0,他引:1  
针对混合柔性流水车间多种工艺路线的生产调度问题,分析了生产工艺计划与车问调度系统的集成原理,建立目标模型,通过将简单遗传算法加以改进,在建立集成模型的基础上,对算法进行研究,把进化后的遗传算法(SGA)和改进的模拟退火算法(SA)有机结合,使算法优化机制融合和优化结构互补,形成较为高效的混合优化算法,并对问题进行求解。最后给出了一个具体算例,验证算法的有效性和先进性。  相似文献   

18.
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。  相似文献   

19.
A Modified Genetic Algorithm for Job Shop Scheduling   总被引:9,自引:0,他引:9  
As a class of typical production scheduling problems, job shop scheduling is one of the strongly NP-complete combinatorial optimisation problems, for which an enhanced genetic algorithm is proposed in this paper. An effective crossover operation for operation-based representation is used to guarantee the feasibility of the solutions, which are decoded into active schedules during the search process. The classical mutation operator is replaced by the metropolis sample process of simulated annealing with a probabilistic jumping property, to enhance the neighbourhood search and to avoid premature convergence with controllable deteriorating probability, as well as avoiding the difficulty of choosing the mutation rate. Multiple state generators are applied in a hybrid way to enhance the exploring potential and to enrich the diversity of neighbour-hoods. Simulation results demonstrate the effectiveness of the proposed algorithm, whose optimisation performance is markedly superior to that of a simple genetic algorithm and simulated annealing and is comparable to the best result reported in the literature.  相似文献   

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