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1.
近年来对超前/延误(E/T)排序问题进行了广泛的研究.本文总结了对E/T排序问题的各种研究中的一些特别领域,虽然没有覆盖所有的新成果,但对该课题有兴趣的读者提供了指导.  相似文献   

2.
We address the problem of processing a set of jobs on a single machine under random due dates with a common distribution. The processing times of the jobs are exponentially distributed random variables with means i , and the machine is subject to stochastic breakdowns governed by a Poisson process. Each job i is associated with a job-dependent weight w i . The objective is to schedule the jobs so as to minimize the expected sum of the weighted earliness and tardiness costs of all jobs, which are quadratic functions of the deviations of job completion times from the due dates. We show that the problem is NP-complete. Nevertheless, important optimality properties exist, which can be utilized to develop effective algorithms to solve the problem. Specifically, we prove that, in the case where the weights assigned to both the earliness and tardiness are symmetric, an optimal sequence for the problem must be V-shaped with respect to { i /w i }, in the sense that the sequence will first process jobs in a nonincreasing order of { i /w i } and then in a nondecreasing order of { i /w i }. In the case where asymmetric weights are assigned to the earliness and tardiness costs, the optimal sequence must also be V-shaped with respect to { i /w i }, if the due dates are exponentially distributed. Dynamic programming algorithms are proposed which can find the best V-shaped sequences.  相似文献   

3.
在当今的自动化制造系统中,计算机控制的抓钩的排序直接影响系统的生产率。本文研究了产品在系统的一边装载、而在另一边卸载的电镀线周期性排序问题。工件在每个工作站的处理时间在给定时间范围内,工作站之间没有缓冲槽,相同轨道上的两个抓钩用于工作站之间工件的运送,目标是对运送进行排序以极小化生产周期。为了求解这个问题,本文提出一个求解方法,所提出的方法首先将生产线分为两个无重叠的区域,并且为每个区域分配一个抓钩,然后,提出了一个给定抓钩分配下的混合整数线性规划模型。通过求解不同抓钩分配下模型的最优解,并且选择这些解中最好的一个,以便得到最优解,一个标杆示例被运行,以表明该方法的应用。另外,给出有多重处理槽工序问题的模型和求解方法。  相似文献   

4.
张燕  周支立 《运筹与管理》2009,18(6):136-145
多联票据的印刷过程包括排版、单联印刷和多联配页与装订三个过程。该过程是柔性的流水生产线与装配混合的生产系统。本文研究了该系统中的票据印刷生产调度问题,目标是最小化所有产品的最大完成时间(Makespan)。该问题到目前为止还没有人研究,本文首先建立了该问题的混合整数规划模型,然后提出了该模型的求解方法,并给出了该问题的下界。最后的量化示例和算例试验表明本文的模型是有效的。  相似文献   

5.
一个超前有奖迟后受罚的排序问题   总被引:4,自引:0,他引:4  
本文考虑货物装卸管理中船主和港口之间的下述相互制约关系;有n条船在同一时刻到达同一港口,因而也希望在同一时刻完成装卸货物。如某船的货物不能如期装卸完,船主会向港方索取赔偿,反之,如货物提前装卸完,则船主会向港方付取奖金,因此从港方来说是适当考虑n条船的一个装卸程序以使总费用最少。对这样一个NP-困难的排序问题,本文给出了一个动态规划解法,且在逆一致性条件下给出了一伪多项式时间的动态规划算法。  相似文献   

6.
讨论了混合Flow Shop环境下的提前/滞后调度问题,这是一个NP-难题。为此,首先给出了问题的数学模型,然后构造了一个有效的遗传算法。最后给出了实验结果和结论。  相似文献   

7.
We consider the problem of assigning a common due-date and sequencing a set of simultaneously available jobs on several identical parallel-machines. The objective is to minimize some penalty function of earliness, tardiness and due-date values. We show that the problem is NP-hard with either a total or a maximal penalty function. For the problem with a total penalty function, we show that the special case in which all jobs have an equal processing time is polynomially-solvable.  相似文献   

8.
针对非一致并行机环境下特殊工艺约束提前/拖后调度问题,设计了一个基于向量组编码的新遗传算法,此算法的编码方法简单,能有效地反映实际调度方案,即清楚地反映出每机器加工产品的代号和顺序.引入浓度概念,对种群中浓度高的个体进行抑制,从而增加群体多样性,同时,利用爬山算法对种群中个体进行局部搜索,提高了种群质量,加快了收敛速度.仿真结果表明,此算法是有效的,适用于解实际的此类调度问题.  相似文献   

9.
This paper considers the problem of hybrid flowshop scheduling. First, we review the shortcoming of the available model in the literature. Then, four different mathematical models are developed in form of mixed integer linear programming models. A complete experiment is conducted to compare the models for performance based on the size and computational complexities. Besides the models, the paper proposes a novel hybrid particle swarm optimization algorithm equipped with an acceptance criterion and a local search heuristic. The features provide a fine balance of diversification and intensification capabilities for the algorithm. Using Taguchi method, the algorithm is fine tuned. Then, two numerical experiments are performed to evaluate the performance of the proposed algorithm with three particle swarm optimization algorithms available in the scheduling literature and one well-known iterated local search algorithm in the hybrid flowshop literature. All the results show the high performance of the proposed algorithm.  相似文献   

10.
范志强 《运筹与管理》2013,22(2):235-242
分析了以箱组为任务对象QCSP与以整贝为任务对象QCSP的异同,指出前者更能均衡各岸桥作业负荷,并减少船舶装卸作业时间。考虑到岸桥具有作业效率差异的特点,将其视为同类平行机调度问题,同时结合任务优先约束、岸桥作业不可相互穿越与安全距离等特有约束,建立了更加符合实际的以箱组为任务对象的岸桥作业调度混合整数规划模型,其优化目标是最小化装卸作业的makespan。针对模型求解的复杂度,设计了一种遗传算法,对算法搜索空间进行了讨论,并推导了问题的低界。实验算例表明所建立的模型能够反映岸桥作业调度过程中作业效率差异及任务优先约束现象,其算法能够在允许的运算时间内获得稳定的满意解,并且优化结果要全面优于以整贝为任务对象QCSP的调度方案。  相似文献   

11.
A scheduling problem with piecewise linear (PL) optimization extends conventional scheduling by imposing a conjunction of combinatorial PL constraints involving the objective function variables. To solve this problem, this paper presents a hybrid algorithm where Constraint Programming (CP) search is supported and driven by a (integer) linear programming solver running on a well-controlled subproblem which is dynamically tightened. The paper discusses and compares different ways of decomposing the problem constraints between the CP search and the solver. We show how the subproblem structure and the piecewise linearity are exploited by the search.  相似文献   

12.
The classical deterministic scheduling problem of minimizing the makespan on unrelated parallel processors is known to be NP-hard in the strong sense. Given the mixed integer linear model with binary decision variables, this paper presents heuristic algorithms based on partial enumeration. Basically, they consist in the construction of mixed integer subproblems, considering the integrality of some subset of variables, formulated using the information obtained from the solution of the linear relaxed problem. Computational experiments are reported for a collection of test problems, showing that some of the proposed algorithms achieve better solutions than other relevant approximation algorithms published up to now.  相似文献   

13.
Heuristics which have been developed for transport scheduling over a lengthy period starting in 1960 are presented. They are generated in response to requirements to solve practical problems, and most are now in regular use by bus and train companies. Mathematical programming models have been formulated for some of the problems, but have been inappropriate on their own; in some cases, heuristics have led to a reduced problem which has then been solved by integer linear programming. The paper is designed to illustrate the development of heuristics for a range of related problem areas over nearly forty years. It explores the relationships between heuristics and other approaches and emphasises the need to convince users of the suitability of the overall system. Where appropriate, indications are given of difficulties in achieving practical implementation.  相似文献   

14.
本文综述了近年来国内外对宽容交货中排序问题的研究.  相似文献   

15.
轩华  刘静  李冰 《运筹与管理》2014,23(2):244-249
为满足实际生产环境对工件加工顺序和工件到达时间的要求,提出了具有新特征的单机总加权拖期调度问题,其特点体现在:工件有动态到达时间,且由工件优先级关系构成的优先级图为非连接图且存在环的情况,对该问题建立数学规划模型,在扩展Tang和Xuan等的基础上,提出了结合双向动态规划的拉格朗日松弛算法求解该问题。在该算法的设计中,提出双向动态规划算法求解拉格朗日松弛问题,使得它可处理优先级图中一个工件可能有多个紧前或紧后工件的情况,采用次梯度算法更新拉格朗日乘子,基于拉格朗日松弛问题的解设计启发式算法构造可行解。实验测试结果显示,所设计的拉格朗日松弛算法能够在较短的运行时间内得到令人满意的近优解,为更复杂的调度问题的求解提供了思路。  相似文献   

16.
具有学习效应的超前有奖延误受罚的排序问题(英文)   总被引:1,自引:0,他引:1  
本文考虑具有学习效应和共同交货期的单机排序问题.目标函数是加权超前有奖延误受罚总和.我们的目标是寻找一个最优序使得目标函数的值最小.由于该问题是NP-hard的,我们给出一些特殊情况下多项式时间可解的特例.同时在快速估计下界的基础上给出了分支定界算法来求一般情况下的最有排序.  相似文献   

17.
Moukrim  A.  Quilliot  A. 《Order》1997,14(3):269-278
The general non preemptive multiprocessor scheduling problem (NPMS) is NP-Complete, while in many specific cases, the same problem is Time-polynomial. A first connection between PMS and linear programming was established by Yannanakis, Sauer and Stone, who associated to any PMS instance some specific linear program. The main result inside this paper consists in a characterization of the partially ordered structures which allow the optimal values of any associated PMS instance to be equal to the optimal values of the corresponding linear programs.  相似文献   

18.
单台机器E-T随机排序问题的多项式算法   总被引:1,自引:0,他引:1  
本文研究排序问题中的E—T问题,工件在单台机器上加工,n个工件的加工时间都为整数P,相同的工期d为离散分布,满足∑i=1^mP(d=ξi)=1,其中ξ为整数,目标是使E(∑(Ei+Tj))的期望值最小。应用贪婪算法和二分法思想,我们提出解决该问题的一个最优算法,并得出该算法的复杂性为O(nmlogp)。  相似文献   

19.
天然气稳态运行优化问题的难点在于网络结构复杂、规模大、目标函数及约束高度非线性.针对其混合整数非线性规划模型,基于网络约简和线性化技术,建立了线性近似模型,并提出一种新的求解算法.将新算法用于优化我国西部天然气管网系统,结果表明所提算法是有效的.  相似文献   

20.
基于整数规划的驾驶员调度系统-TRACS II   总被引:1,自引:0,他引:1  
本阐述一个世界名的成功的公共交通驾驶员调度系统-TRACSⅡ。该系统的核心算法是基于整数规划的“生成与选择”方法。本首先对驾驶员调度同题以及TRACS⒓系统的研发背景和主要功能进行简要介绍;然后,重点阐述该系统的整数规划模型和求解方法;最后,举出几个成功应用的实例,并归纳出该系统存在的局限性,为进一步研究指出方向。  相似文献   

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