基于多方法协作优化方法的非壅塞式固体火箭冲压发动机导弹一体化优化设计

固体火箭冲压发动机和导弹性能相互之间紧密耦合。从导弹总体方案设计阶段引入一体化设计思想,能充分发挥和协调好固体火箭冲压发动机和导弹的性能,提高了导弹的总体设计水平。采用基于遗传算法、Powell法和模式搜索法的多方法协作优化方法进行了以非壅塞式固体火箭冲压发动机为动力的导弹总体一体化优化设计。算例表明,采用该多方法协作优化方法进行一体化优化设计,可以协调导弹的总体参数,提高导弹的总体性能。     

邻域加强的并行子空间优化过程

针对基于响应面的并行子空间优化(CSSo-RS)过程的不足,提出了基于邻域加强的改进CSSO-RS优化过程.其主要思路是在子空间优化后,在得到的最优解附近进行全部变量的优化,以更好地协调系统级优化与子空间优化.用经典测试函数及通用航空飞机参数优化问题对该算法进行测试,测试结果表明该算法使CSSO-RS优化效率得到较大的...     

Balancing a one‐way corridor capacity and safety‐oriented reliability: A stochastic optimization approach for metro train timetabling

In urban rail transit systems of large cities, the headway and following distance of successive trains have been compressed as much as possible to enhance the corridor capacity to satisfy extremely high passenger demand during peak hours. To prevent train collisions and ensure the safety of trains, a safe following distance of trains must be maintained. However, this requirement is subject to a series of complex factors, such as the uncertain train braking performance, train communication delay, and driver reaction time. In this paper, we propose a unified mathematical framework to analyze the safety‐oriented reliability of metro train timetables with different corridor capacities, that is, the train traffic density, and determine the most reliable train timetable for metro lines in an uncertain environment. By employing a space‐time network representation in the formulations, the reliability‐based train timetabling problem is formulated as a nonlinear stochastic programming model, in which we use 0‐1 variables to denote the time‐dependent velocity and position of all involved trains. Several reformulation techniques are developed to obtain an equivalent mixed integer programming model with quadratic constraints (MIQCP) that can be solved to optimality by some commercial solvers. To improve the computational efficiency of the MIQCP model, we develop a dual decomposition solution framework that decomposes the primal problem into several sets of subproblems by dualizing the coupling constraints across different samples. An exact dynamic programming combined with search space reduction strategies is also developed to solve the exact optimal solutions of these subproblems. Two sets of numerical experiments, which involve a relatively small‐scale case and a real‐world instance based on the operation data of the Beijing subway Changping Line are implemented to verify the effectiveness of the proposed approaches.     

A stochastic gradual cover location problem

Covering models assume that a point is covered if it is within a certain distance from a facility and not covered beyond that distance. In gradual cover models it is assumed that a point is fully covered within a given distance from a facility, then cover gradually declines, and the point is not covered beyond a larger distance. Gradual cover models address the discontinuity in cover which may not be the correct approach in many situations. In the stochastic gradual cover model presented in this article it is assumed that the short and long distances employed in gradual cover models are random variables. This refinement of gradual cover models provides yet a more realistic depiction of actual behavior in many situations. The maximal cover model based on the new concept is analyzed and the single facility location cover problem in the plane is solved. Computational results illustrating the effectiveness of the solution procedures are presented. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

串联系统预防维修周期优化策略研究(英文)

针对串联系统建立了基于可靠性约束的预防性维修优化模型,该模型充分考虑到预防维修可以提高系统可靠性的同时,其故障率会随着维修次数的增加而上升,引入役龄回退因子对预防维修活动前后系统性能的动态变化进行了描述.通过实例验证了该优化模型的正确性与可用性,对模型作进一步的扩展,还可用于更一般复杂的串并联系统.     

炮兵作战决策方案优选的方法

炮兵作战方案的选择,是炮兵作战指挥决策的关键环节,其合理与否,直接关系到炮兵作战效能的发挥和作战的成败.根据炮兵作战的实际,阐述了炮兵作战方案优选的依据,给出了运用层次分析法确定影响作战方案选择的各因素权重的方法步骤,在对优选依据的建模要素进行分析的基础上,构建了每个要素的效用函数计算模型,并给出了评估方案的计算方法,提供了模型应用的一般步骤.     

攻击机靶场效能优化:概念、方法与基本问题

系统阐述了攻击机靶场攻击、靶场效能以及靶场效能优化等基本概念,在此基础上,分析了攻击机靶场效能优化的基本任务和基本问题,并给出了形式化描述。     

MEFP战斗部结构的正交优化设计

以多爆炸成型弹丸(MEFP)为计算模型,应用显式有限元程序LS-DYNA,分析了药型罩间距、锥角、壁厚、装药高度和装药直径5种因素对MEFP发散角的影响规律。结果表明:随着药型罩间距、壁厚和装药直径的增加以及药型罩锥角、装药高度的减小,MEFP的发散角在减小。在此基础上以MEFP发散角为命中和毁伤概率指标,应用正交优化方法针对5种结构因素对MEFP发散角的影响主次关系进行了分析研究。结果表明药型罩壁厚是MEFP战斗部命中和毁伤概率的主要影响因素,并得到了5种结构因素各水平的最优组合。     

常规导弹战前运输任务优化模型

制定常规导弹战前运输计划时,各车辆运输时间和运输路线的安排是一个组合优化问题.运用军事运筹学和不确定性优化理论,充分考虑节点冲突性、车辆隐蔽性、任务时间、道路容量等因素,建立了运输任务方案的优化模型.该研究为常规导弹波次作战计划的制定和优化提供模型支持,有助于提高常规导弹作战指挥自动化和部队的生存能力.     

Quantifying optimal mesh and ring design costs

During the last decade telecommunication operators have been deploying WDM (Wavelength Division Multiplexing) technology to satisfy the exponential growth in global communication. While facilitating the advanced information society of today, this has also led to a higher dependency on the networks, and furthermore the high capacity utilization of optical fibers means that a single link failure will influence many users and enterprises. For these reasons, protection of network connections has become a major competitive parameter for the operators. Currently, the most popular protection method is ring protection, due to its simplicity, requiring only basic management functionality and operating with local restoration control. While many optical rings have been deployed, little work has been published on exactly what the cost of ring networks are, compared to general mesh networks. In this article we perform a quantitative comparison between ring protection and mesh protection, using real world network data and realistic prices for network components. Extending classic LP flow models to take rings and node costs into account, and using a link‐path based mesh network LP model, we are able to perform a total cost comparison of the two architectures, and of manual ring network design. The results suggest that the price of mesh network components must be reduced significantly to be competitive with ring based networks, and also that manual network design does not necessarily lead to the most cost‐efficient designs. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2005