卫星在役考核相关问题研究

各类卫星在现代战争中发挥着重要和关键作用。我国传统的卫星试验和鉴定具有很强的科研试验性质,承制单位和用户重点关注的是性能检验,较少考虑作战效能和部队适用性等指标。为推动卫星装备建设和应用,装备试验鉴定部门初步组织开展了相应的在役考核工作。文章对比了美军装备作战试验与鉴定、我国作战试验与在役考核的概念;提出卫星在役考核的六大特点;分析卫星在役考核的组织方式、组织机构和组织保障的不足,提出相应发展建议;研究卫星在役考核指标体系设计、分析评估方法、问题反馈与整改等方面的不足,并提出相应措施建议。     

多旋翼无人机减振分析与实验

针对多旋翼无人机机身系统振动过大导致飞行状态不稳的问题,基于有限元仿真技术与实验方法,进行了减振分析。通过频率分析,确定系统振动过大的原因为固有频率与激励频率耦合导致的共振现象,且共振频点的模态振型包含一阶挥舞、一阶摆振和二阶摆振振型。提出了优化机身壳体截面形状的设计方案,在不增加额外质量的情况下,将一阶挥舞、一阶摆振和二阶摆振振型对应的频点分别提高37.23%、22.47%和18.43%,有效规避了机身共振现象。仿真实验证明,提出的有限元仿真与实验结合的减振分析思〖BHDWG8,WK10YQ,DK1*2,WK1*2D〗〖XCMWL.TIF;%129%129〗听语音 聊科研与作者互动 路及优化设计方法,可为旋翼无人机减振设计提供参考依据。     

基于邻域最优控制理论的中制导弹道簇生成

针对临近空间高超声速目标飞行速度快,跟踪预测难的特点,提出了在中制导阶段进行最优弹道设计与弹道簇生成用于对目标预测命中区域进行有效覆盖的方法。首先,通过分析临近空间高超声速目标对现有防空体系带来的挑战,阐明了在中制导段进行弹道簇设计与生成的必要性,其次,将中制导段的弹道规划问题视为求解满足多种约束条件下的最优控制问题,应用最优化理论方法得到了基准的最优弹道,再次,应用邻域最优控制理论,针对终端约束条件进行调整,设计了邻域最优弹道簇的生成算法。最后,通过仿真验证了所提方法的有效性。     

A search game on a cyclic graph

There is a finite cyclic graph. The hider chooses one of all nodes except the specified one, and he hides an (immobile) object there. At the beginning the seeker is at the specified node. After the seeker chooses an ordering of the nodes except the specified one, he examines each nodes in that order until he finds the object, traveling along edges. It costs an amount when he moves from a node to an adjacent one and also when he checks a node. While the hider wishes to maximize the sum of the traveling costs and the examination costs which are required to find the object, the seeker wishes to minimize it. The problem is modeled as a two‐person zero‐sum game. We solve the game when unit costs (traveling cost + examination cost) have geometrical relations depending on nodes. Then we give properties of optimal strategies of both players. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004.     

A balancing problem for mixed model assembly lines with a paced moving conveyor

We state a balancing problem for mixed model assembly lines with a paced moving conveyor as: Given the daily assembling sequence of the models, the tasks of each model, the precedence relations among the tasks, and the operations parameters of the assembly line, assign the tasks of the models to the workstations so as to minimize the total overload time. Several characteristics of the problem are investigated. A line‐balancing heuristic is proposed based on a lower bound of the total overload time. A practical procedure is provided for estimating the deviation of any given line‐balance solution from the theoretical optimum. Numerical examples are given to illustrate the methodology. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004.     

Flow shop scheduling with earliness,tardiness, and intermediate inventory holding costs

We consider the problem of scheduling customer orders in a flow shop with the objective of minimizing the sum of tardiness, earliness (finished goods inventory holding), and intermediate (work‐in‐process) inventory holding costs. We formulate this problem as an integer program, and based on approximate solutions to two different, but closely related, Dantzig‐Wolfe reformulations, we develop heuristics to minimize the total cost. We exploit the duality between Dantzig‐Wolfe reformulation and Lagrangian relaxation to enhance our heuristics. This combined approach enables us to develop two different lower bounds on the optimal integer solution, together with intuitive approaches for obtaining near‐optimal feasible integer solutions. To the best of our knowledge, this is the first paper that applies column generation to a scheduling problem with different types of strongly ????‐hard pricing problems which are solved heuristically. The computational study demonstrates that our algorithms have a significant speed advantage over alternate methods, yield good lower bounds, and generate near‐optimal feasible integer solutions for problem instances with many machines and a realistically large number of jobs. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004.     

一种用于机电产品测试性设计的传感器优选MINLP模型

在单故障假设条件下,考虑了传感器的失效概率和设备的故障率,提出一种以故障检测率和故障隔离率为约束条件的降低传感器费用和失效概率的混合整数非线性规划(MINLP)模型,从而为机电产品测试性设计中传感器选择问题提供了一种可行和有效的解决方法,并进行了案例验证,说明了该方法的有效性。     

利用几何结构求解欧氏平面TSP的改进遗传算法

TSP是经典的组合优化问题。根据欧氏平面TSP最优环路的性质提出了子路径及相关的概念,利用点集凸壳设计了环路构造算法,并以点集Delaunay三角剖分图为启发信息设计了改进的遗传算法,通过中国144城市TSP等验证了算法的有效性。     

A spatial rank‐based multivariate EWMA control chart

Nonparametric control charts are useful in statistical process control when there is a lack of or limited knowledge about the underlying process distribution, especially when the process measurement is multivariate. This article develops a new multivariate self‐starting methodology for monitoring location parameters. It is based on adapting the multivariate spatial rank to on‐line sequential monitoring. The weighted version of the rank‐based test is used to formulate the charting statistic by incorporating the exponentially weighted moving average control scheme. It is robust to non‐normally distributed data, easy to construct, fast to compute and also very efficient in detecting multivariate process shifts, especially small or moderate shifts which occur when the process distribution is heavy‐tailed or skewed. As it avoids the need for a lengthy data‐gathering step before charting and it does not require knowledge of the underlying distribution, the proposed control chart is particularly useful in start‐up or short‐run situations. A real‐data example from white wine production processes shows that it performs quite well. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 59: 91–110, 2012     

基于模糊商空间理论的产品粒化过程分析

模块形成与划分是展开模块化设计及大规模定制生产的关键环节。为了进一步扩展产品模块化的定量分析手段,提出了一种基于模糊商空间理论的产品粒化方法。通过引入粒度计算,将基于相关性分析的产品模块化过程转化为基于粒度计算的产品粒化过程,并应用模糊商空间理论对其进行了分析,给出了基于归一化距离和综合模糊相似关系的产品粒度空间构建方法,建立了基于两阶段优化算法的最佳产品粒层确定流程,进而得到了最优模块划分方案,最后以某堆垛机货叉机构为例对该方法进行了有效性验证。此方法为产品模块聚类与优化提供了一种新的数值分析和评价手段,应用结果表明该方法具有一定的可行性和合理性,能够有效指导产品模块化过程的实施。