基于三方动态博弈模型的网络生存防御策略优化配置

针对网络攻防环境中防御方以提高系统生存能力为目的所进行的最优生存防御策略的选取问题,提出了一种基于完全信息动态博弈理论的生存防御策略优化配置算法。将恶意攻击方、故障意外事件及防御方作为博弈的参与人,提出了一种混合战略模式下的三方动态博弈模型,对博弈的主要信息要素进行了说明,以混合战略纳什均衡理论为基础,将原纳什均衡条件式的表达式转化为可计算数值结果的表达式,并据此增加了近似的概念,最后,将提出的模型和近似纳什均衡求解算法应用到一个网络实例中,结果证明了模型和算法的可行性和有效性。     

A model to predict the residual life of aircraft engines based upon oil analysis data

This paper reports on a study using the available oil monitoring information, such as the data obtained using the Spectrometric Oil Analysis Programme (SOAP), to predict the residual life of a set of aircraft engines. The relationship between oil monitoring information and the residual life is established using the concept of the proportional residual, which states that the predicted residual life may be proportional to the wear increment measured by the oil analysis programmes. Assuming such a relationship between wear and the residual life exists, we formulated a recursive prediction model for the item's residual life given measured oil monitoring information to date. A set of censored life data of 30 aircraft engines (right censored due to preventive overhaul) along with the history of their monitored metal concentration information are available to us. The metal concentration information includes many variables, such as Fe, Cu, Al, etc.; not all of them are useful, and some of them may be correlated. The principal component analysis (PCA) has been adopted to reduce the dimension of the original data set and to produce a new set of uncorrelated variables, which we shall use in the prediction model. The procedure associated with estimating model parameters is discussed. The model is fitted to the actual SOAP data from the aircraft engines, and the goodness‐of‐fit test has been carried out. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.     

The effect of catastrophes on the strategic customer behavior in queueing systems

We consider the single server Markovian queue subject to Poisson generated catastrophes. Whenever a catastrophe occurs, all customers are forced to abandon the system, the server is rendered inoperative and an exponential repair time is set on. During the repair time new arrivals are allowed to join the system. We assume that the arriving customers decide whether to join the system or balk, based on a natural linear reward‐cost structure with two types of rewards: A (usual) service reward for those customers that receive service and a (compensation) failure reward for those customers that are forced to abandon the system due to a catastrophe. We study the strategic behavior of the customers regarding balking and derive the corresponding (Nash) equilibrium strategies for the observable and unobservable cases. We show that both types of strategic behavior may be optimal: to avoid the crowd or to follow it. The crucial factor that determines the type of customer behavior is the relative value of the service reward to the failure compensation. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

The economic effects of international trade in armaments in the major western industrialized and developing countries†

We have used the Michigan Model of World Production and Trade to assess the impact of exports and imports of armaments (based on 1980 data) on sectoral trade and employment and other economic variables in the major Western trading countries. If the United States were to place a unilateral embargo on its arms exports and imports, we calculate that it would experience a comparatively small amount of employment displacement in the aggregate and that most of this displacement would occur in the transport equipment and electric machinery sectors. If all the major Western countries were to place a multilateral embargo on their arms trade, the sectoral effects on the United States would be similarly small. But the sectoral effects in several other industrialized and developing countries measured as a percentage of sectoral employment, would be larger, indicating potential short‐run adjustment problems in labor markets in some cases.     

基于面向对象技术的柴油机在线状态监测系统设计

将软件设计中的面向对象思想扩展到系统设计中,针对柴油机实车运行在线监测中的变速变载及空间有限等问题,基于CAN总线的可靠性、信息传输的实时性和多主工作方式,设计分布式智能监测节点和上位机监控中心．分布式监测节点同步采集柴油机运行数据并进行降噪和简单特征提取后,将实时采样数据和在线监测结果上传至基于嵌入式PCI04的上位机监控中心,进行二次特征提取和智能模式识别,从而实现柴油机在线状态监测与故障预警和诊断．     

一种基于层次分析法的舰炮武器系统选型综合评价模型

针对舰炮武器系统选型配置决策中众多制约因素难以平衡兼顾的难题,本文基于层次分析法,综合了作战效能、全寿命周期费用、研制周期、适装性、技术可行性和发展潜力等多变量因素,提出并建立了一套综合优化舰炮武器系统选型配置方案的方法和模型,实现了舰炮武器系统选型配置问题的优化决策,最后以大口径主炮武器系统发展选型为例,给出了模型的应用实例。     

经验模态分析法在雷达信号脉内分析中的应用

雷达脉内特征分析是信号分选领域一个重要手段,当脉内信号有多个雷达信号交叠在一起时,很难分析出其各自的调制方式。经验模态分解(EMD)在分析非平稳混合信号时效果显著,但其存在2个明显弊端。针对端点效应问题,首先采用小波分解将信号分解成各分量,随后对除噪声外的各分量利用ARMA模型对信号进行预测,接着对预测后的各分量进行小波重构,从而消除了端点效应,针对虚假分量的问题,结合雷达信号的特点改进了其终止条件,提高了EMD分解的性能。最后,对EMD分解后的各分量进行时频分析,得出雷达脉内信号的调制特征。仿真验证了算法的有效性。     

一种基于改进的ROUSTIDA算法的数据补齐方法

针对ROUSTIDA数据补齐方法存在的问题,提出了一种改进的ROUSTIDA数据补齐方法.该方法首先将条件属性与决策属性区分对待,优先填补决策属性值,避免了不一致决策表的产生;然后,在决策属性相同的前提下填补条件属性缺失值,扩展了原算法的使用范围;最后,通过一个实例说明改进算法补齐后的决策表的确能够获得更集中的决策规则...     

利用径向力平衡飞行控制的航天器高精度轨道捕获方法

为实现对探测器轨道形状与高度的精准调整,提出一种径向力平衡飞行的航天器连续推力控制新方法。建立连续推力平衡飞行的动力学极坐标模型,并推导出特殊条件下的解析轨道解,进一步分析边值条件,给出连续推力的控制律。利用这一平衡飞行控制理论,构建轨道捕获的最优控制策略。考虑推力器的推力水平,通过一次或多次的控制过程,实现对轨道形状、轨道高度及轨道相位的综合调整。数值仿真表明:利用平衡飞行的轨道控制方法,配置微小推力器的空间引力波探测器可以实现高精度的轨道捕获;该方法具有控制过程可解析、计算量小、简便、实用等特点。     

泥沙传输方程广义初边值问题的解析解与差分解比较

Cheng提出了泥沙传输问题的广义底边界条件并导出了具有复杂形式的解析解 ,解析解的求解过程中还需求解两个超越方程。本文一方面分析了解析解的复杂性 ,简化了超越方程根的搜索区间 ,另一方面 ,通过数值试验 ,得到了一类稳定的差分格式 ,格式参数为 0 .48≤Θ ≤ 1 ,数值例子表明 :对于稳定的差分格式 ,差分数值解具有很好的逼近效果。