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基于改进混合遗传算法安排生产调度 总被引:1,自引:0,他引:1
研究了某工厂生产调度问题,建立了数学模型.针对这一实际问题,通过引入小生境技术、最优保存策略、近优淘汰策略、自适应调整交叉概率和变异概率,设计了用于求解多个最优顺序的混合遗传算法,用所设计的混合遗传算法对该模型进行了计算,获得了许多最优顺序,这就使得生产调度安排灵活机动,便于智能调度,同时生产量比原来大幅度提高.这表明使用混合遗传算法安排生产调度是非常有效的. 相似文献
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考虑一个由单一制造商和多销售点构成的二级集中式供应链,制造商采用积欠订货策略生产和销售产品,因而面临生产、运输和积欠订货型库存分配与补货的联合决策问题.综合考虑了延迟交货成本、库存持有成本、运输成本和生产成本,建立了最大化总利润的非线性混合整数规划模型,以联合优化供应链的生产、运输及库存分配方案.证明了最优的产品生产分配方案应该具有的结构性质:各个销售网点在任意销售间隔期末同时出现缺货或者库存剩余.同时,提出了基于逐级求解策略的分层求解算法,保证了解的全局最优性.最后,敏感性分析表明:单位产品的库存持有成本与延迟交货成本对最优分配次数及生产量的影响作用相反,固定运输成本也会影响制造商的分配方案及生产计划,但三者均不会影响每个间隔期末的产品分配方案(分配量). 相似文献
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重大突发事件发生后,若灾区的应急物资需求不能通过调用储备得到满足,则应急生产将成为灾区应急物资供应的重要保障手段。本文研究重大突发事件发生后应急物资生产任务的优化问题,重点关注原材料生产能力变化对完成应急生产任务的影响,以应急生产任务完成时间最短、完成成本最低为决策目标,研究了包含多个供应商、多个制造商以及单个受灾点的应急物资生产任务多目标规划模型。运用在求解多目标规划问题时具有众多优势的非支配排序多目标遗传算法(NSGA-II)对模型进行求解。通过算例分析,NSGA-II可以得到较好的Pareto前沿,并且可以根据不同情况给出最优的应急物资生产和原材料保障方案。本文的研究还表明,要想更快完成应急生产任务,需要做好原材料、资金、电力、交通等各种要素的配套保障工作。 相似文献
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本文研究滚装码头混合泊位分配和劳动力分配的联合调度优化问题。首先,考虑潮汐时间窗约束、装卸劳动力约束、泊位缆桩分布约束以及泊位不规则布局因素,建立以最小化船舶总服务时间为目标的混合整数规划模型。其次,采用内外嵌套算法设计策略,提出求解该类问题的组合算法。其中,外层是多种群并行进化的遗传算法,生成多种船舶计划顺序,内层为基于规则的启发式算法,用于计算给定计划顺序的目标函数值。然后,基于实际运营数据,生成多组不同规模的算例进行全面数值实验,结果表明所提出的算法可在10分钟内求解包含50艘船、100个泊段的算例。最后,开展基于真实滚装码头运营实例的案例分析,对所提模型和算法在实际码头调度问题中的适用性与高效性进行验证。 相似文献
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直营连锁企业一直面临着一个重要的决策问题是生产多少产品按什么分配方案供应给它的连锁店进行销售,使得连锁企业的损失最小和利润最大.文章首先建立了连锁企业在给定总生产量和基于期望损失下的单周期最优分配模型,导出了生产分配供应的最优策略公式,提出了求解最优生产总量和最优分配供应策略的近似计算方法,以及在销售周期内打折定价策略.最后通过对某食品直营公司的销售数据进行计算,所提近似算法可以获得连锁公司对应的最优分配供应策略,数值结果表明采用最优分配供应策略可以减少直营连锁企业的期望损失风险,增加期望收益.文章给出了连锁企业最优生产供应策略的模型和近似求解算法,对于连锁企业的生产和分配供应具有重要的理论指导意义. 相似文献
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This paper investigates a large-scale scheduling problem in the iron and steel industry, called color-coating production scheduling (CCPS). The problem is to generate multiple production turns for the galvanized coils that dynamically arrive from upstream lines within a given scheduling horizon, and at the same time determine the sequence of these turns so that the productivity and product quality are maximized while the production cost and the number of generated turns are minimized. We formulate this problem as a mixed integer nonlinear program and propose a tabu search heuristic to obtain satisfactory solutions. Results on real production instances show that the presented model and heuristic are more effective and efficient with comparison to manual scheduling. A practical scheduling system for CCPS combining the model and heuristic has been developed and successfully implemented in a major iron and steel enterprise in China. 相似文献
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在单件订货型生产过程的计划、控制及管理中,生产能力的评估具有十分重要的意义和作用.生产能力包括两个方面:一是技术和设备性能相关的生产能力,一是生产时间相关的生产能力.前者主要是定性的,相对来说易于评估;后者是定量的,由于单件订货型生产的特点,使得这种生产能力成为任务相关的.通过对单件订货型生产中生产时间相关生产能力特点的分析,针对设备和工序任务,提出了基于任务的生产能力的概念及一些相关的定义;并进一步给出了生产能力的计算算法. 相似文献
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The master-slave paradigm finds important applications in parallel computer scheduling, semiconductor testing, machine scheduling, transportation, maintenance management and other industrial settings. In the master-slave model considered in this paper a set of jobs is to be processed by a system of processors. Each job consists of a preprocessing task, a slave task and a postprocessing task that must be executed in this order. The pre- and post-processing tasks are to be processed by a master processor while the slave task is processed by a slave processor. In this paper, we motivate the master-slave model and develop bounded performance approximation algorithms for the unconstrained makespan minimization problem as well as for multiple master systems.This work was supported in part by the National Science Foundation under grant MIP-9103379 and the Army Research Office under grant DAA H04-95-1-0111. 相似文献
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将仿真技术和遗传算法相结合,根据生产车间的资源情况、优化目标等建立了生产调度仿真模型,然后对仿真输出结果进行统计,针对统计结果应用遗传算法对调度决策进行优化.仿真优化结果说明了该集成优化方法是有效性的. 相似文献
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在传统的并行机器调度问题基础上引入了不确定随机变量,同时考虑了以产品外包为能力拓展形式的现代生产模式,建立了基于外包决策的并行调度随机模型.模型以带有拖期惩罚函数的最大化利润为目标,以遗传算法这种进化的启发式计算方法寻找最优解.同时引入虚拟机器的概念,实现了对外包情形下机器调度问题的有效处理和简化.实例证明,该模型更符合现代生产模式,极大地提高了企业的工作效率和经济效益. 相似文献
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Mark S. Squillante Yanyong Zhang Anand Sivasubramaniam Natarajan Gautam 《Annals of Operations Research》2008,160(1):227-255
This paper introduces a generalization of the classical parallel-server fork-join queueing system in which arriving customers
fork into multiple tasks, every task is uniquely assigned to one of the set of single-server queues, and each task consists
of multiple iterations of different stages of execution, including task vacations and communication among sibling tasks. Several
classes of dynamic polices are considered for scheduling multiple tasks at each of the single-server queues to maintain effective
server utilization. The paper presents an exact matrix-analytic analysis of generalized parallel-server fork-join queueing
systems, for small instances of the stochastic model, and presents an approximate matrix-analytic analysis and fixed-point
solution, for larger instances of the model. 相似文献
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A multiple-objective hierarchical production planning and scheduling model is developed that integrates aggregate type decisions, family disaggregate decisions, lotsizing and scheduling of the jobs. It is assumed that demand and production failure are subject to uncertainties. Stochastic programming with recourse using a constraint sample approximation method is used to incorporate random demand and production failure into the model. The model evaluates final production plans, updates the demand forecasts and proceeds on a rolling horizon manner. Experimental results show that it is sufficient to generate and incorporate into the aggregate type model a small sample of the stochastic constraints from an infinite set of scenarios. A heuristic scheduling algorithm provides detailed information regarding the progress of jobs through work centers. This information is extremely useful in resolving infeasibilities during the production process. Other features of the model are also reported. 相似文献
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M Kumral 《The Journal of the Operational Research Society》2011,62(1):60-68
Economic characterization of mining parcels depends upon geo-metallurgical properties, which vary throughout orebody. Mine production scheduling should aim to obtain maximum utility from orebody in such a way as to ensure mine–mill reconciliation. As heterogeneity of geo-metallurgical variables increases, the scheduling will be a very complicated task. Geo-metallurgical and financial data used in the mine production scheduling are based on simulation and/or estimation generated from sparse drilling and unknown future events. Therefore, the scheduling process involves a significant degree of uncertainty. In order to deal with the uncertainty stemmed from geo-metallurgical and financial variables, two approaches are recommended in this paper. Firstly, mine production scheduling is formulated as a problem of stochastic programming with recourse. The extraction periods of mining blocks are treated as the first-stage variables and the block destinations represents a recourse vector. It is observed that the solution is implicitly robust. Secondly, the scheduling is expressed as a maximin problem to extract more uniform metal quantity in periods to coincide with mill requirements instead of maximization of net present value because the blending constraint in the traditional approach forces more uniform production. In the case where there is correlation between grade and geo-metallurgical variables, this model generates reasonably good results. 相似文献