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1.
考虑由两个代理引起的重新排序问题,其中每个代理都在公共的加工资源下完成各自的不可中断加工的工件.每个代理要求在仅依赖工件的完工时间时最小化某一个特定的目标函数.考虑在原始工件的完工时间限制下的两个代理的单机最小化最大延误时间的重新排序问题.证明了该问题能在多项式时间或者拟多项式时间内解决.  相似文献   

2.
考虑工件具有加工位置上限最小化总加权误工量的单机排序问题.在此排序问题中,每个工件J_j都具有一个加工位置上限k_j.也就是说,如果工件J_j是一个可行排序中的第x个工件,那么就需要满足x≤k_j.证明了(ⅰ)当工件具有相同工期时,该排序问题是二元NP-难的并且是拟多项式时间可解的,(ⅱ)当工件具有单位权重时,该排序问题是一元NP-难的.  相似文献   

3.
张新功 《运筹学学报》2013,17(1):98-105
研究具有加工时间之和学习效应下的一个新型成组排序问题,工件的学习效应是之前工件加工时间之和的函数,组学习效应是成组加工所在的位置的函数. 考虑最大完工时间和总完工时间两个问题,证明了这两个问题都是多项式时间可解的,并提出了相应的多项式时间算法.  相似文献   

4.
考虑工件具有加工位置上限最小化总加权误工量的单机排序问题.在此排序问题中,每个工件Jj都具有一个加工位置上限kj.也就是说,如果工件Jj是一个可行排序中的第x个工件,那么就需要满足xkj.证明了(i)当工件具有相同工期时,该排序问题是二元NP-难的并且是拟多项式时间可解的,(ii)当工件具有单位权重时,该排序问题是一元NP-难的.  相似文献   

5.
何程  韩鑫鑫 《运筹学学报》2018,22(3):109-116
有两个代理A和B, 每个代理都各自有一个工件集. 同一个代理的工件可以在同一批中加工, 而且每一个代理都有一个需要最小化的函数. 研究在无界平行分批处理机上同时最小化代理A的最大费用和代理B的最大完工时间问题, 并给出一个算法, 它可在多项式时间内找到关于这个问题的所有Pareto最优点.  相似文献   

6.
考虑时间和位置相关的单机排序问题, 且机器具有退化的维修限制. 工件的实际加工时间是工件加工位置相关的函数, 目标函数为最大完工时间和总完工时间两个函数, 并利用匹配算法给出这两个问题的多项式时间算法. 最后得出工件满足一定条件时最大完工时间满足组平衡规则.  相似文献   

7.
研究了工件具有子工件工期的排序问题.需要在一台单机上加工若干个给定的工件.每个工件由若干个子工件组成,每个子工件都有各自的工期.只有当工件的每个子工件都按时完成,才能称该工件是按时完工工件,否则,称该工件产生延误.目标是最大化按时完工的工件个数.证明当每个工件都被分成两个子工件时,该问题是NP-难的,而且不存在完全多项式时间近似方案(fully polynomial time approximation scheme,简记为FPTAS).提出两个启发式算法,利用数值模拟比较它们的性能,并且将这两个启发式算法的解与最优解的上界进行比较.  相似文献   

8.
研究在所有工件的正常加工时间均相同的情况下具有指数学习效应和凸资源约束的单机排序问题.给出了两种模型:在资源消耗总费用有限的情况下,以工件的最大完工时间为目标函数;在工件的最大完工时间有限的情况下,以资源消耗总费用为目标函数.求两种模型下的最优排序和最优资源分配,使得目标函数最小.证明这两个问题都是多项式时间可解的,并给出了相应的算法.  相似文献   

9.
研究了与总误工损失相关的两个代理的单机排序问题。第一个代理以工件的总误工损失为目标函数,第二个代理以工件的总完工时间或总误工工件数为目标函数。目标是寻找一个排序,使得在第二个代理的目标函数不超过给定的上界的条件下,第一个代理的目标函数值最小。对这两个与总误工损失相关的两个代理的单机排序问题,分别给出它们的拟多项式时间的动态规划算法。  相似文献   

10.
研究带有固定区间的两个代理单机排序问题.第一个代理工件可中断,且工件到达时间与工期满足一致关系,目标函数为最小化总误工.第二个代理工件被安排在固定时间窗口.目标是寻找一个排序,使得满足第二个代理目标可行情况下,第一个代理目标函数值最小.在固定区间等于加工时间的情况下,利用分块原则,提出了一个伪多项式时间动态规划算法,并给出了固定区间大于加工时间情况下的时间复杂度分析.  相似文献   

11.
We consider multi-agent scheduling on a single machine, where the objective functions of the agents are of the max-form. For the feasibility model, we show that the problem can be solved in polynomial time even when the jobs are subject to precedence restrictions. For the minimality model, we show that the problem is strongly NP-hard in general, but can be solved in pseudo-polynomial-time when the number of agents is a given constant. We then identify some special cases of the minimality model that can be solved in polynomial-time.  相似文献   

12.
研究同时具有退化工件和老化效应的单机可拒绝排序问题,即工件的实际加工时间是与其开工时间和所在位置有关的函数,同时生产商可以通过支付一定的处罚费用而拒绝加工某些工件。在生产加工过程中,考虑对机器进行选择性维修活动来提高加工的效率;机器进行维修活动后将恢复到初始状态,老化效应也将重新开始。目标是确定拒绝哪些工件、何时进行维修活动以及接受工件集中工件的次序,以便极小化接受加工工件的最大完工时间与拒绝加工工件总处罚费用的和。证明得到了所研究的问题是NP-难解的,并给出了解决问题的一个全多项式时间近似方案(FPTAS)算法。  相似文献   

13.
In this paper we consider the problem of minimizing number of tardy jobs on a single batch processing machine. The batch processing machine is capable of processing up to B jobs simultaneously as a batch. We are given a set of n jobs which can be partitioned into m incompatible families such that the processing times of all jobs belonging to the same family are equal and jobs of different families cannot be processed together. We show that this problem is NP-hard and present a dynamic programming algorithm which has polynomial time complexity when the number of job families and the batch machine capacity are fixed. We also show that when the jobs of a family have a common due date the problem can be solved by a pseudo-polynomial time procedure.  相似文献   

14.
This paper considers the discrete two-hub location problem. We need to choose two hubs from a set of nodes. The remaining nodes are to be connected to one of the two hubs which act as switching points for internodal flows. A configuration which minimizes the total flow cost needs to be found. We show that the problem can be solved in polynomial time when the hub locations are fixed. Since there are at most ways to choose the hub locations, the two-hub location problem can be solved in polynomial time. We transform the quadratic 0–1 integer program of the single allocation problem in the fixed two-hub system into a linear program and show that all extreme points of the polytope defined by the LP are integral. Also, the problem can be transformed into a minimum cut problem which can be solved efficiently by any polynomial time algorithm.  相似文献   

15.
In this paper we study the job shop scheduling problem under the assumption that the jobs have controllable processing times. The fact that the jobs have controllable processing times means that it is possible to reduce the processing time of the jobs by paying a certain cost. We consider two models of controllable processing times: continuous and discrete. For both models we present polynomial time approximation schemes when the number of machines and the number of operations per job are fixed.  相似文献   

16.
Two-agent scheduling to minimize the total cost   总被引:1,自引:0,他引:1  
Two agents, each having his own set of jobs, compete to perform their own jobs on a common processing resource. Each job of the agents has a weight that specifies its importance. The cost of the first agent is the maximum weighted completion time of his jobs while the cost of the second agent is the total weighted completion time of his jobs. We consider the scheduling problem of determining the sequence of the jobs such that the total cost of the two agents is minimized. We provide a 2-approximation algorithm for the problem, show that the case where the number of jobs of the first agent is fixed is NP-hard, and devise a polynomial time approximation scheme for this case.  相似文献   

17.
研究了带有拒绝的单机和同型机排序问题. 对于单机情形, 工件的惩罚费用是对应加工时间的\alpha倍.如果工件有到达时间, 目标为最小化时间表长与惩罚费用之和, 证明了这个问题是可解的.如果所有工件在零时刻到达, 目标为最小化总完工时间与惩罚费用之和, 也证明了该问题是可解的.对于同型机排序问题, 研究了工件分两批在线实时到达的情形, 目标为最小化时间表长与惩罚费用之和.针对机器台数2和m, 分别给出了竞争比为2和4-2/m的在线算法.  相似文献   

18.
Interval Scheduling problems (IS) address the situation where jobs with fixed start and fixed end times are to be processed on parallel identical machines. The optimization criteria of interest are the maximization of the number of jobs completed and, in case weights are associated with jobs, the subset of jobs with maximal total weight. We present polynomial solutions to several IS problems and study computational complexity issues in the situation where bounds are imposed on the total operating time of the machines. With this constraint, we show that tractability is achieved again when job preemption is allowed.  相似文献   

19.
研究具有若干固定工件和自由工件,其中固定工件必须在指定时间窗内加工,而自由工件具有不同交工的时间,并且其加工可以中断的单机排序问题,其目标是极小化工件的误工数.该问题可以表示为1|FB,rj,pmtn|∑j Uj.首先讨论了问题的几个重要性质,以此为基础建立了求解该问题的动态规划算法,其时间复杂度为O(n4+m log m),其中m和n分别是固定工件数和自由工件数.  相似文献   

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