舰载机回收任务的优化调度算法及仿真

针对舰载机回收过程中,飞行甲板跑道容量的瓶颈问题,比较了几种常见的排序算法,并运用Mat-lab和Lingo软件分别对先来先服务、基于最早到达时刻、滑动窗3种算法进行了计算机仿真。仿真结果表明,滑动窗排序法排序结果最好。最后,指出了滑动窗初始窗口飞机数目和移动步长对算法复杂度和排序结果的影响。     

On scheduling with ready-times,due-dates and vacations

A single machine sequencing problem is considered in which there are ready-time and due-date constraints on jobs and vacation constraints on the machine. Each vacation has fixed starting and finish time and no preemption is allowed for the jobs. The objective is to minimize maximum lateness. An intriguing feature of this formulation is that it allows sequencing in disconnected time windows. A relaxation of the problem is obtained by modeling the vacations as a set of jobs with flexible ready-times and artificial due-dates and a branch and bound algorithm is developed for the problem. In the algorithm, the search is not only guided by the bounds but also by a careful manipulation of the artificial due-dates. Consequently; while searching in the relaxed solution space, solutions of the original problem are implicitly enumerated. Computational results indicate that the algorithm can satisfactorily solve problems with multiple vacations.     

基于粗糙集和TOPSIS的弹药目标匹配研究

针对多种弹药打击同一目标的弹种选取顺序问题,即弹药目标匹配顺序问题,从弹药毁伤和目标抗毁伤机理人手,构建弹药目标匹配指标体系,利用粗糙集理论约简弹药目标匹配指标体系并确定指标的客观权重,运用加权TOPSIS确定弹药目标综合匹配顺序,为最优火力分配决策提供了理论依据。     

On some sequencing problems

The (mxn) sequencing problem may be characterized as follows: There are m machines which can produce a piece consisting of n parts. Each part has a determined order in which it is processed through the machines. It is assumed that each machine cannot deal with more than one part at a time and that the processing required for each part can be accomplished only on one machine. That is, the machines are all specialized so that alternate machines for the same processing on a part is not possible. The problem is to find the best production plan consisting in sequencing the different parts so as to make the whole amount of time from the beginning of work till the piece is completed the shortest possible. Such a plan is called an optimum one. In the first 4 sections of this paper, the problem (2xn) is solved for the (2xn) case in which the order in which parts come on the machine is not constrained by further assumptions. The remainder of the paper then takes up: 1) the (3xn) problem of Bellman-Johnson (viz. the technological processing order through the machine is the same for all parts) for several new special cases; 2) the 2xn problem of sequencing when delay times must also be considered; and, 3) some properties of an approximating method for solving (mxn) problems, including a delineation of cases when the approximating method will yield optimal solutions.     

灰色关联投影法的威胁排序算法

威胁评估与排序是作战系统和C4I系统必须具备的重要功能.结合多指标决策理论和灰色系统理论,提出了基于多指标决策灰色关联投影法的威胁排序算法.首先通过建立灰色关联判断矩阵将威胁排序转化为多指标决策问题;其次为缩小极端值的影响提出了基于信息熵的威胁指标权重算法;最后从矢量投影角度应用灰色关联投影值进行威胁排序;并分别研究了分辨系数和指标权重对威胁排序的影响.通过现代防空作战实例验证了算法的有效性和工程实用性.     

On sequencing with earliest starts and due dates with application to computing bounds for the (n/m/G/Fmax) problem

Recent efforts to improve lower bounds in implicit enumeration algorithms for the general (n/m/G/F_max) sequencing problem have been directed to the solution of an auxiliary single machine problem that results from the relaxation of some of the interference constraints. We develop an algorithm that obtains optimal and near optimal solutions for this relaxed problem with relatively little computational effort. We report on computational results achieved when this method is used to obtain lower bounds for the general problem. Finally, we show the equivalence of this problem to a single machine sequencing problem with earliest start and due date constraints where the objective is to minimize the maximum lateness.     

Prospects for creating a regional security structure in the Middle East

‘The Middle East talks the talk, but it doesn't walk the walk’, argues Heller when relating to attempts by parties in the region to create some kind of a cooperative security relationship. Concepts of regional security have simply been grafted onto traditional political-military doctrine, with the result that multilateralism has become just another vehicle for pursuing long-standing policy. He shows this with regard to the Middle East peace process as well as the Barcelona Process and attempts to forge a Euro-Mediterranean Partnership. What should be done in order to promote the process? Heller's conclusion is that moving along the track of cognitive convergence while bypassing the sequencing problem by simultaneously pursuing both peace and security building will help mitigate some of the major problems in regional security.     

基于AHP算法的精确作战目标价值排序问题研究

针对精确作战中的目标价值排序问题,从战场实际出发建立了目标价值体系,并在此基础上应用AHP原理提出了目标价值排序的递阶层次结构模型．通过成对比较实现作战目标价值的精确排序,为指挥员基于目标价值的决策提供理论依据．     

Scheduling with parallel processors and linear delay costs

This paper deals with the sequencing problem of minimizing linear delay costs with parallel identical processors. The theoretical properties of this m-machine problem are explored, and the problem of determining an optimum scheduling procedure is examined. Properties of the optimum schedule are given as well as the corresponding reductions in the number of schedules that must be evaluated in the search for an optimum. An experimental comparison of scheduling rules is reported; this indicates that although a class of effective heuristics can be identified, their relative behavior is difficult to characterize.     

Scheduling of parallel processors: A posterior bound on LPT sequencing and a two-step algorithm

This article considers the problem of scheduling parallel processors to minimize the makespan. The article makes two key contributions: (1) It develops a new lower bound on the makespan for an optimal schedule, and (2) it proposes an efficient two-step algorithm to find schedules of any desired accuracy, or percent above optimal. In addition, a posterior bound on LPT (longest processing time) sequencing is developed in the article. It is proved that this bound dominates the previously reported bounds on LPT sequencing.     

An improved branch and bound procedure for n × m flow shop problems

This paper considers the classical nXm flow shop sequencing problem. An improved branch and bound procedure is proposed. Computational experience shows that the proposed procedure is more efficient compared to the existing optimizing procedures.     

基于集对分析的目标威胁评估与排序研究

在分析以往目标威胁评估与排序方法不足的基础上,提出了基于集对分析的多因素威胁评估方法,以定量的结果对目标的威胁程度进行综合评估,为威胁评估与排序问题寻求出一种新的方法,其评估结果可为指挥员对空情威胁做出正确判断提供科学依据。     

基于灰色网络分析法的目标价值排序研究

以炮兵战场目标价值评价指标体系为基础,运用网络分析法确定指标权重,运用灰色系统理论确定评价灰类和总灰色评价权向量,建立基于灰色网络分析法的目标价值评价模型,旨在向指挥员提供可靠的目标攻击顺序建议,帮助指挥员开展后续的最优火力分配等决策工作。通过实例验证了评估模型的合理性和实用性。     

Elimination methods in the m × n sequencing problem

This paper considers elimination methods in solving the sequencing problem where no passing is permitted. An elimination method consists of reducing (according to some criterion) the initial set of n solutions to a smaller set. A crucial question arises as to whether this reduced set contains an optimal solution. The answer is affirmative if this elimination criterion implies condition (3).     

An experimental comparison of solution algorithms for the single-machine tardiness problem

A basic problem in scheduling involves the sequencing of a set of independent tasks at a single facility with the objective of minimizing mean tardiness. Although the problem is relatively simple, the determination of an optimal sequence remains a challenging combinatorial problem. A number of algorithms have been developed for finding solutions, and this paper reports a comparative evaluation of these procedures. Computer programs for five separate algorithms were written and all were run on a data base designed to highlight computational differences. Optimizing algorithms developed by Emmons and by Srinivasan appeared to be particularly efficient in the comparative study.     

A convex property of an ordered flow shop sequencing problem

A flow shop sequencing problem with ordered processing time matrices is considered. A convex property for the makespan sequences of such problems is discussed. On the basis of this property an efficient optimizing algorithm is presented. Although the proof of optimality has not been developed, several hundred problems were solved optimally with this procedure.     

Simulations to explore alternative sequencing rules

A flexible simulation system has been designed to permit investigation of sequencing rules in a large job shop, with continual input of new work. The objective is to understand what happens rather than to find optimum rules, with many conflicting measures of effectiveness: work in process, finished goods investment, delays, machine and labor utilization, and effort to implement. A few problem areas have been explored.     

On the assignment and sequencing of operations on a crew-served project

This paper is concerned with assigning and sequencing a set of activities for some or all members of a crew of operators so that the completion time of all such operations is minimized. It is assumed that each of the operators in the crew possesses, initially, certain tasks that only he can perform. A branch-and-bound scheme is proposed to treat the problem, and suitable computational experience is provided.     

Dynamic scheduling in single-server multiclass service systems with unit buffers

The problem of optimal dynamic sequencing for a single-server multiclass service system with only unit storage (buffer) space at each queue is considered. The model is applicable to many computer operating and telecommunicating systems (e.g., polling systems). Index policies to minimize costs for the special case of symmetric arrival rates are derived. Simulations suggest that using these indices provides a substantial improvement over cyclic schedules.     

A parallel sequencing algorithm for minimizing total cost

The problem of sequencing jobs on parallel processors when jobs have different available times, due dates, penalty costs and waiting costs is considered. The processors are identical and are available when the earliest job becomes available and continuously thereafter. There is a processor cost during the period when the processor is available for processing jobs. The proposed algorithm finds the sequence (or sequences) with minimum total cost (sum of waiting, penalty and processor costs.). A proof of the algorithm and numerical results are given.