已知工件最大加工时间的两台同类机半在线问题

考虑已知工件最大加工时间的两台同类机半在线问题．机器M1,M2的速度分别为s1=1,s2=s(s≥1),工件是一个一个独立地到来,工件的信息是逐个释放的,但所有工件中加工时间为最大的工件的加工时间是已知的,目标函数为极小化最大机器负载．此模型简记为Q2／known largest job／Cmax．作者给出了Qmax2算法并证明此算法的竞争比为2(s 1)/s 2(1≤s≤2)和(s 1)/s(s>2),且是紧的．同时给出Q2／known largest job／Cmax问题的一个下界,并且证明Qmax2算法的竞争比与最优算法竞争比之差不大于1/4.     

两台平行机的实时到达在线排序

本文考虑一的的在线平行机排序模型－－实时到达在线问题,该模型中,工件是陆续到达的,工件的个数及到达时间是事先未知的,而且只有当工件到达,才知其加工时间,所求目标是使所有工件都加工完的时间达到最小,对两台平行机的情形,Ｃｈｅｎ与Ｖｅｓｔｊｅｎｓ给出近似比为３／２的线ＬＰＴ算法,并证明了不存在近似小于（５－√５）／２的算法,我们利用黄金分割数设计了一个 算法,其近似比不超过（１８－√５）／１１。     

双目标优化排序问题1/r_j,UET/L_(max)∩C_(max)

本文首先证明排序问题１／ｒｊ／Ｃｍａｘ的“随手加工”法则，然后在此基础上对１／ｒｊ，ＵＥＴ／Ｌｍａｘ∩Ｃｍａｘ给出一个多项式最优化算法．     

带有装卸服务器的两台平行机调度问题的LS和LPT算法

研究带有一个装载服务器和一个卸载服务器的两台平行机调度问题.每个工件在加工前必须由装载服务器安装到机器上,加工结束后由卸载服务器从机器上进行卸载.装载和卸载时间均为单位时间,目标是极小化最大完工时间.该问题是NP难问题,文章主要分析LS和LPT两个经典的启发式算法,分别证明了这两个算法的紧界为11/7和7/6改进了已有结果.     

工件可自由下线最小化总完工时间的有界平行分批排序

考虑工件可自由下线最小化总完工时间的有界平行分批排序问题.在该问题中,一台平行批机器可以同时处理b个工件作为一个平行批,这里b是批容量,一个批的加工时间等于分配给这个批的工件的最大加工时间.关于可自由下线工件,每一个工件的完工时间等于包含这个工件的批的开工时间与工件的加工时间的和.也就是,如果一个批■有一个开工时间S,那么包含在批■中的每一个工件乃的开工时间定义为S,而它的完工时间定义为S+p_j,这里p_j是工件J_j的加工时间.对此问题,首先研究最优排序的一些性质.然后,基于这些性质,给出一个运行时间为O(n~(b(b-1))的动态规划算法.     

工件可自由下线最小化总完工时间的平行分批排序问题

考虑工件可自由下线最小化总完工时间的有界平行分批排序问题. 在该问题中, 一台平行批机器可以同时处理 b 个工件作为一个平行批, 这里b 是批容量, 一个批的加工时间等于分配给这个批的工件的最大加工时间. 关于可自由下线工件, 每一个工件的完工时间等于包含这个工件的批的开工时间与工件的加工时间的和. 也就是, 如果一个批B 有一个开工时间S, 那么包含在批B 中的每一个工件J_j 的开工时间定义为S, 而它的完工时间定义为S+p_j, 这里p_j 是工件J_j 的加工时间. 对此问题, 首先研究最优排序的一些性质. 然后, 基于这些性质, 给出一个运行时间为O(n^{b (b-1)})的动态规划算法.     

加工时间和尺寸成正比单机排序和工件运输的最小化最大完工时间问题

在单机排序和工件运输的最小化最大完工时间问题中,工件首先在一台机器上加工,然后被一辆有容量限制的汽车运送到一个顾客．当工件的加工时间和尺寸无关时, Chang和Lee已经证明该问题是强NP困难的．他们也给出了一个启发式算法,它的最差执行比为5／3,并且这个界是紧的．本文考虑工件的加工时间和尺寸成正比的情形,证明了Chang和Lee的算法有更好的最差执行比53／35,并提供了一个新的启发式算法,它的最差执行比是3／2,并且这个界是最好的．     

带交货期的工件族生产与配送的排序问题

本文考虑了多个客户订购不同种类的工件,工件生产完后需要运输到客户的单机供应链排序问题.由于工件属于不同的种类,在加工不同种类工件前要有一个准备时间.每个客户分布在不同位置,客户的每个工件都有一个交货期,工件是分批配送的,每一批配送需要花费一定的时间及费用.考虑了两个与交货期有关的目标函数,分别给出了它们的最优算法.     

求带释放时间的半导体煅烧排序的最短交付时间的一个高效PTAS

本文研究一个目标是最小化最大交付时间的能分批处理的非中断单机排序问题．这个问题来源于半导体制造过程中对芯片煅烧工序的排序．煅烧炉可以看成一个能同时最多加工B（〈n）个工件的处理机．此外，每个工件有一个可以允许其加工的释放时间和一个完成加工后的额外交付时间．该问题就是将工件分批后再依批次的排序加工，使得所有工件都交付后所需的时间最短．我们设计了一个用时O（f（l／ε）n^5/2）的多项式时间近似方案，其中关于1／ε的指数函数厂（1／ε）对固定的ε是个常数.     

具有两个不相容工件族单位工件的有界分批在线排序问题

研究具有两个不相容工件族单位工件单机有界平行分批的在线排序问题.工件按时在线到达,目标是最小化最大完工时间.在有界平行分批排序中,容量有限制机器最多可将b个工件形成一批同时加工,每个工件及每一批的加工时间为1.不相容工件族是指来自不同工件组的工件不能放在同一批加工.对该问题提供了一个竞争比为■的最好可能的在线算法.     

Parallel machines scheduling to minimize job tardiness and machine deteriorating cost with deteriorating jobs

This paper studies the parallel machines bi-criteria scheduling problem (PMBSP) in a deteriorating system. Sequencing and scheduling problems (SSP) have seldom considered the two phenomena concurrently. This paper discusses the parallel machines scheduling problem with the effects of machine and job deterioration. By the machine deterioration effect, we mean that each machine deteriorates at a different rate. This deterioration is considered in terms of cost which depends on the production rate, the machine’s operating characteristics and the kind of work done by each machine. Moreover, job processing times are increasing functions of their starting times and follow a simple linear deterioration. The objective functions are minimizing total tardiness and machine deteriorating cost. The problem of total tardiness on identical parallel machines is NP-hard, thus the problem with machine deteriorating cost as an additional term is also NP-hard. We propose the LP-metric method to show the importance of our proposed multi-objective problem. A metaheuristic algorithm is developed to locate optimal or near optimal solutions based on a Tabu search mechanism. Numerical examples are presented to show the efficiency of this model.     

Single machine scheduling with batch deliveries

The single machine batch scheduling problem is studied. The jobs in a batch are delivered to the customer together upon the completion time of the last job in the batch. The earliness of a job is defined as the difference between the delivery time of the batch to which it belongs and its completion time. The objective is to minimize the sum of the batch delivery and job earliness penalties. A relation between this problem and the parallel machine scheduling problem is identified. This enables the establishment of complexity results and algorithms for the former problem based on known results for the latter problem.     

带工件相容约束的单机分批排序问题

The single machine parallel batch problem with job compatibility is considered to minimize makespan,where the job compatibility constraints are represented by a graph G.This problem is proved to be NP-hard.And when the graph G is limited to be a general bipartite,a complete bipartite and a complete m-partite graph,these problems are solved in polynomial time respectively.     

工作有到达时间且拒绝工件总个数受限的单机平行分批排序问题的近似算法

考虑了工件有到达时间且拒绝工件总个数不超过某个给定值的单机平行分批排序问题.在该问题中,给定一个工件集和一台可以进行批处理加工的机器.每个工件有它的到达时间和加工时间;对于每个工件来说要么被拒绝要么被接受安排在机器的某一个批次里进行加工;一个工件如果被拒绝,则需支付该工件对应的拒绝费用.为了保证一定的服务水平,要求拒绝工件的总个数不超过给定值.目标是如何安排被接受工件的加工批次和加工次序使得其最大完工时间与被拒绝工件的总拒绝费用之和最小.该问题是NP-难的,对此给出了伪多项式时间动态规划精确算法,2-近似算法和完全多项式时间近似方案.     

Parallel machine scheduling with general sum of processing time based models

In this paper, we analyse the parallel machine makespan minimization problem with the general sum of processing time based learning or aging effects. First, we prove that an optimal solution to the single machine case can be found by priority rules. Next, for the considered parallel machine problem, we construct the exact dynamic programming algorithm that can operate on real-valued job processing times, which is the only exact algorithm for the analysed problem. The computational analysis confirms that it can solve optimally moderate problem instances.     

Two meta-heuristics for parallel machine scheduling with job splitting to minimize total tardiness

Parallel machine scheduling is a popular research area due to its wide range of potential application areas. This paper focuses on the problem of scheduling n independent jobs to be processed on m identical parallel machines with the aim of minimizing the total tardiness of the jobs considering a job splitting property. It is assumed that a job can be split into sub-jobs and these sub-jobs can be processed independently on parallel machines. We present a mathematical model for this problem. The problem of total tardiness on identical parallel machines is NP-hard. Obtaining an optimal solution for this type of complex, large-sized problem in reasonable computational time by using an optimization solver is extremely difficult. We propose two meta-heuristics: Tabu search and simulated annealing. Computational results are compared on random generated problems with different sizes.     

Scheduling parallel machines with single vehicle delivery

We investigate the integrated production and distribution scheduling problem in a supply chain. The manufacturer’s production environment is modeled as a parallel machine system. A single capacitated vehicle is employed to deliver products in batches to multiple customers. The scheduling problem can also be viewed as either parallel machines with delivery considerations or a flexible flowshop. Different inventory holding costs, job sizes (volume or storage space required in the transportation unit), and job priorities are taken into account. Efficient mathematical modeling and near-optimal heuristic approaches are presented for minimizing total weighted completion time.     

加工时间可控和简单线性增长的平行机排序

本文研究加工时间可控并随开工时间简单线性增长的平行机排序问题.证明了该问题为NP-难问题,该问题存在满足以下性质的最优排序:每个工件的加工时间要么完全压缩,要么完全不压缩;每台机器的工件排序由一个工件参数和控制变量的函数的递增序给出.通过将问题等价转换为0-1非线性整数规划问题,给出了平行机排序问题的贪婪算法.     

A scheduling problem with job values given as a power function of their completion times

This paper deals with a problem of scheduling jobs on the identical parallel machines, where job values are given as a power function of the job completion times. Minimization of the total loss of job values is considered as a criterion. We establish the computational complexity of the problem – strong NP-hardness of its general version and NP-hardness of its single machine case. Moreover, we solve some special cases of the problem in polynomial time. Finally, we construct and experimentally test branch and bound algorithm (along with some elimination properties improving its efficiency) and several heuristic algorithms for the general case of the problem.     

带两个服务等级的三台机最优在线算法

研究了带服务等级约束的三台平行机在线排序问题.每台机器和每个工件的服务等级为1或者2,工件只能在等级不高于它的机器上加工,即等级为1的工件只能在等级为1的机器上加工,等级为2的工件可在所有机器上加工.每个工件的加工时间为一个单位,目标是极小化所有工件的总完工时间.考虑两种情形:当一台机器等级为1,两台机器等级为2时,给出了竞争比为17/14的最优在线算法;当两台机器等级为1,一台机器等级为2时,给出了竞争比为43/36的最优在线算法.