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1.
单台批处理机总加权完成时间最小化的启发式算法   总被引:1,自引:0,他引:1  
冯大光  唐立新 《控制与决策》2006,21(11):1293-1297
批处理机总加权完成时间最小化问题的复杂性目前还没有确定,因此有必要研究该问题的启发式算法.基于对该问题最优解性质的分析,提出了工件分批的最优性质.分别基于WSPT规则和SPT规则对工件进行总排序,利用工件最优分批性质进行分批,提出了两种启发式算法(简称WSPTS和SPTS).为了检验算法的性能.将提出的算法与此问题的基准算法和常规算法进行了比较,结果表明,启发式算法WSPTS要优于其他的算法,而SPTS算法的性能最优.  相似文献   

2.
陈可嘉  王潇 《控制与决策》2013,28(10):1502-1506
针对两机无等待流水车间调度问题,提出目标函数最大完工时间最小化的快速算法,并给出算法的复杂度。分析两机无等待流水车间调度问题的排列排序性质,证明了两机无等待流水车间调度问题的可行解只存在于排列排序中,排列排序的最优解一定是两机无等待流水车间调度问题的最优解。最后研究了同时包含普通工件和无等待工件的两机流水车间调度问题的复杂性,为进一步研究两机无等待流水车间调度问题提供了理论依据。  相似文献   

3.
Job Shop 排序问题解空间定量分析   总被引:4,自引:0,他引:4  
讨论Job shop排序问题不可行解的构造情况,给出了不可行解的一个充要条件以及2台机器n个加工工件的Job shop问题不可行解和可行解的计算公式,并由此得到一种概率模型的计算方法。通过计算发现,Job shop排序问题的不可行解所占比例非常大。  相似文献   

4.
考虑机器容量有限的同时加工排序问题, 为享有公共交货期窗口[e; d]的n个工件分批并排序以最小化总的赋权提前/延误惩罚. 本文把窗时排序与同时加工排序结合起来研究, 假设每个批的容量是b(< n, 其中n为工件的个数), 而且最早交货期e 和最晚交货期d已知. 但该问题是NP–完备的, 首先给出最优排序的几条性质, 进而解决了两类特殊情况.  相似文献   

5.
首先将加工多工件类型的无等待机器人制造单元调度问题分解为两个相互联系的子问题:(1)多类型工件进入系统的排序问题;(2)机器人搬运作业的排序问题。从解决工件使用工作站和机器人可能发生的冲突入手,以工件进入系统的时间为决策变量,利用禁止区间法建立了问题的数学模型,并开发了一基于图论的动态分枝定界最优算法。最后,通过一自动化印刷电路板(PCB)生产线和随机算例验证了算法的有效性。  相似文献   

6.
能耗总成本已成为生产调度中一个重要考虑因素,需要在最大完成时间和能耗总成本之间进行权衡,论文将遗传算法(GA)应用到考虑能耗的单机批调度中,并建立同时优化最大化完成时间和最小化能耗总成本的差异工件单机批调度模型.通过遗传算法在考虑能耗(CEC)和不考虑能耗(IEC)下求出非支配解集,利用工件分批的优化和对遗传选择算子的改进,以保证搜索的效率.实验结果表明,与IEC相比,在CEC下使用遗传算法求出的解效果更好,且随着问题规模的增大和工件加工功率的增加,所得解的优势更加明显.  相似文献   

7.
给定m台平行机(同型机),n个工件,寻找一种分配方案,使得把这n个工件分配到m台机器后,整体完工时间尽可能短,这个NP-难问题被称为经典排序问题。如果每个工件的加工时间满足一定的条件,则有望能在多项式时间内有效地得到最优的分配方案。Yue等对加工时间满足整除性质的经典排序问题考虑了一种新的算法,该算法总是能得到这种特殊情况的最优分配。该算法在多项式时间内能够得到最优分配,是对于一般的经典排序问题的近似算法。文章在此基础上,考虑该新算法在一般问题上的近似比。文中考虑了这个新算法的两种版本,分别得到了3/2和2-1/2 q(q∈Z+)的近似比。紧例子表明,文中对算法的两个版本的分析都是最优的。  相似文献   

8.
本文研究具有同一交工期和指数加工时间,目标函数是期望的未完工费用的单机随机调度问题,即l1Xj-exp(λj)d1E(ΣICj)工件的最优排序是按ICjλi非升的排序,得到了排序可交换及未完工费用的等价性附加结果。  相似文献   

9.
郭艳东  王庆  黄敏 《自动化学报》2013,39(12):2100-2110
研究了返工工件的单机重调度问题.在初始调度中初始工件带有不同的就绪时间,优化目标为最小化初始工件等待时间和;重调度时在满足每个初始工件最大等待时间约束情况下安排返工工件的生产,优化目标为最小化所有工件等待时间和.文中首先建立了RRSM (Rescheduling for reworks on single machine)问题模型,并证明其为NP难问题.然后,提出并证明了三个RRSM问题性质,进而根据诸性质设计了求解RRSM问题的动态插入启发式(Dynamic insert heuristic,DIH)算法.证明了应用DIH算法能在多项式时间内求得两种特殊RRSM问题的最优解. 最后,分析了DIH算法解的特点,给出了最优解的判定方法,并通过算例说明了DIH算法的有效性.  相似文献   

10.
闫红超  汤伟  姚斌 《计算机应用》2022,42(9):2952-2959
针对置换流水车间调度问题(PFSP),提出了一种混合鸟群算法(HBSA)以更加有效地最小化最大完工时间。首先,为了改善初始种群的质量和多样性,结合一种基于NEH(Nawaz-Enscore-Ham)的启发式算法和混沌映射提出了一种新的种群初始化方法;其次,为了使算法能够处理离散的调度问题,采用最大排序值(LRV)规则将连续的位置值转换为离散的工件排序;最后,为了强化算法对解空间的探索能力,借鉴变邻域搜索(VNS)和迭代贪婪(IG)算法的思想针对个体最佳工件排序和种群最佳工件排序分别提出了局部搜索方法。针对广泛使用的Rec标准测试集进行了仿真测试,并与目前有效的元启发式算法——刘等提出的混合差分进化算法(L-HDE)、混合共生生物搜索算法(HSOS)、离散狼群算法(DWPA)、多班级教学优化算法(MCTLBO)相比较,结果表明,HBSA取得的最佳相对误差(BRE)、平均相对误差(ARE)的平均值比上述四种算法至少下降了73.3%、76.8%,从而证明HBSA具有更强的寻优能力和更好的稳定性。尤其是针对测试算例Rec25和Rec27,仅HBSA的求解结果达到了目前已知最优解,进一步证明了其优越性。  相似文献   

11.
Batch processing machines are frequently encountered in many industrial environments. A batch processing machine is one which can process several jobs simultaneously as a batch. The processing time of a batch is equal to the largest processing time of any job in the batch. This study deals with the problem of scheduling jobs in a flowshop with two batch processing machines such that the makespan is minimized. A heuristic based on Tabu search (TS) technique is proposed. The proposed heuristic is compared with a heuristic based on mixed integer linear programming (MILP). Because the complexity of the MILP-based heuristic is depended on the number of job batches, the comparison is under up-to-eight batches problem. In order to measure the proposed TS-based heuristic in larger batch problem, the relative error percentage with the lower bound (REPLB) is used. The results show that the proposed heuristic is efficient and effective for the problems with relative large job sizes.  相似文献   

12.
李曙光  李国君  王秀红 《软件学报》2006,17(10):2063-2068
考虑无界批量机器并行调度中极小化加权完工时间和问题.设有n个工件和m台批加工同型机.每个工件具有一个正权因子、一个释放时间和一个加工时间.每台机器可以同时加工Bn个工件.一个批次的加工时间是该批次所包含的所有工件的加工时间的最大者.在同一批次中加工的工件有相同的完工时间,即它们的共同开始时间加上该批次的加工时间.给出了一个多项式时间近似方案(PTAS).  相似文献   

13.
This paper studies the problem of integrated control in the 2-dimensional (2D) system with parameter uncertainties for batch processes. An integrated iterative learning control (ILC) strategy based on quadratic performance for batch processes is proposed. It realizes comprehensive control by combining robust ILC in batch-axis with model predictive control (MPC) in time-axis. The design of quadratic-criterion-based ILC for the system can be converted into a min-max problem. Then a model predictive controller with time-varying prediction horizon is designed based on a quadratic cost function. For an uncertain model, a novel integrated robust ILC scheme based on a nominal model is further proposed. As a result, the control law of the 2D system can be regulated during one batch, which leads to good tracking performance and strong robustness against the disturbance and the uncertainties. Moreover, the analyses of the convergence and tracking performance are given. The proposed methods are applied to batch reactor, and results demonstrate that the system has good robustness and convergence. This paper provides a new way for batch processes control.  相似文献   

14.
This paper presents several search heuristics and their performance in batch scheduling of parallel, unrelated machines. Identical or similar jobs are typically processed in batches in order to decrease setup times and/or processing times. The problem accounts for allotting batched work parts into unrelated parallel machines, where each batch consists of a fixed number of jobs. Some batches may contain different jobs but all jobs within each batch should have an identical processing time and a common due date. Processing time of each job of a batch is determined according to the machine group as well as the batch group to which the job belongs. Major or minor setup times are required between two subsequent batches depending on batch sequence but are independent of machines. The objective of our study is to minimize the total weighted tardiness for the unrelated parallel machine scheduling. Four search heuristics are proposed to address the problem, namely (1) the earliest weighted due date, (2) the shortest weighted processing time, (3) the two-level batch scheduling heuristic, and (4) the simulated annealing method. These proposed local search heuristics are tested through computational experiments with data from dicing operations of a compound semiconductor manufacturing facility.  相似文献   

15.
Iterative learning model predictive control for multi-phase batch processes   总被引:1,自引:0,他引:1  
Multi-phase batch process is common in industry, such as injection molding process, fermentation and sequencing batch reactor; however, it is still an open problem to control and analyze this kind of processes. Motivated by injection molding processes, the multi-phase batch process in each cycle is formulated as a switched system with internally forced switching instant. Controlling multi-phase batch processes can be decomposed into two subtasks: detecting the dynamics-switching-time; designing the control law for each phase with considering switching effect. In this paper, it is assumed that the dynamics-switching-time can be obtained in real-time and only the second subtask is studied. To exploit the repetitive nature of batch processes, iterative learning control scheme is used in batch direction. To deal with constraints, updating law is designed by using model predictive control scheme. An online iterative learning model predictive control (ILMPC) law is first proposed with a quadratic programming problem to be solved online. To reduce computation burden, an offline ILMPC is also proposed and compared. Applications on injection molding processes show that the proposed algorithms can control multi-phase batch processes well.  相似文献   

16.
This paper considers a two-stage hybrid flowshop problem in which the first stage contains several identical discrete machines, and the second stage contains several identical batching machines. Each discrete machine can process no more than one task at time, and each batching machine can process several tasks simultaneously in a batch with the additional feature that the tasks of the same batch have to be compatible. A compatibility relation is defined between each pair of tasks, so that an undirected compatibility graph is obtained which turns out to be an interval graph. The batch processing time is equal to the maximal processing time of the tasks in this batch, and all tasks of the same batch start and finish together. The goal is to make batching and sequencing decisions in order to minimize the makespan. Since the problem is NP-hard, we develop several heuristics along with their worst cases analysis. We also consider the case in which tasks have the same processing time on the first stage, for which a polynomial time approximation scheme (PTAS) algorithm is presented.  相似文献   

17.
Rescheduling in near real-time is a problem faced by real batch shop managers. Due to the short lead time, the complexity, the volume of information and lack of planning tools, shop foremen are forced to resolve the problem with little more than intuition and experience. Although much research has been done on the problem of scheduling Flexible Manufacturing Systems (FMSs) the results are not applicable to the general batch shop. We delineate the problem of FMS scheduling as a class distinct from the general batch shop scheduling problem and identify reasons for this lack of suitability.  相似文献   

18.
This paper describes a novel method for heat-up phase control of an industrial batch polymerization reactor where heat transfer characteristics change with batches due to fouling of the polymer products on the reactor wall. The main objective of the control is to settle the reactor temperature on a target value within ± 0.1°C in a minimum possible time. To achieve this goal utilizing the repetitive nature of batch operation, the control problem was defined as a tracking problem and feedback-assisted iterative learning control (FBALC) was employed as the underlying control technique. The proposed control method was applied to an industrial batch reactor polymerizing ABS resin. After on-site evaluation for an extended period of time, it was found that the proposed method gives a pronounced improvement in heat-up phase operation. Consistent heat-up profiles with a minimized settling time are obtained.  相似文献   

19.
This paper considers the rolling batch planning problem of grouping and sequencing a given set of slabs into several rolling units in iron and steel industry. The existing mathematical methods often used for the problem are traveling salesman problem (TSP) and vehicle routing problem (VRP), but these methods are not precise, because the position limitation of some slabs in a rolling unit scheduling is not considered. Therefore we suggest a new model, vehicle routing problem with time window (VRPTW) to describe the rolling batch planning problem, in which the position limitation of slabs are quantified as the time constraints. Several solution methods including the genetic algorithm are presented for solving the problem and the computational results show that the genetic algorithm is superior to other methods.In this paper, the vehicle routing problem with time window (VRPTW) of combinational optimization is used to analyze and model the rolling batch planning problem. Genetic algorithm and heuristic are used to solve the problem. Simulation results based on the actual production data show that this model is precise and the genetic algorithm based method is very promising.  相似文献   

20.
基于广义相关系数法的MPCA在线监控方法   总被引:1,自引:0,他引:1  
针对多向主元分析法(MPCA)在线监控传统方法的预测能力差而常常导致误报、漏报的实际情况,基于广义相关系数法提出一种在线监控方法.从监控模型库中找出与待测多元轨迹之间广义相关系数最大的批次,将该批次监控时间点后的数据作为待测多元轨迹的预测值,得出完整的批次数据,并用多向主元分析法进行监控.用青霉素发酵过程仿真器(Pensimv2 0)进行仿真,结果表明,基于广义相关系数法的在线监控方法与其他传统方法相比,其结果最接近实际过程离线,并减少了由于其他预测方法带来的误差.  相似文献   

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