基于CNS性能及人为因素的纵向碰撞风险研究

为了分析CNS性能及人为因素对航空器在平行航路的安全间距影响,基于雷达管制环境下管制员对航空器纵向穿越的干预过程,在传统碰撞风险模型的基础上引入认知可靠性与失误分析方法(CREAM),综合考虑通信、导航、监视(Communication,Navigation and Surveillance,CNS)性能以及人为因素,建立了包含人的认知可靠性的平行航路纵向碰撞风险模型.并通过算例分析了CNS性能以及人因可靠性对平行航路碰撞风险的影响.结果表明,导航性能对航路的纵向碰撞风险影响较大;通过提高人的认知可靠性可以有效地提高平行航路的安全水平.     

大型复合材料箱体成型模具设计

为了制造合格的大型复合材料箱体,本文制定了箱体成型模具的设计和制造方案.某复合材料箱体属于大型长轴类产品,其成型模具挠曲变形及脱模力大.模具主体采用通长轴、周向辐板、轴向筋板和蒙皮组合的结构形式.模具通过无缝钢管、模具骨架及蒙皮形成的三维网状结构有效保证模具刚度,通过带斜度工作平面及变圆角设计大大降低脱模力,通过在顶出...     

攻击移动目标的末制导导弹命中概率评估方法

针对攻击移动目标的末制导导弹的命中概率评估问题,深入分析了影响导弹精度的各类误差源,研究了目标机动特性对末制导雷达捕获概率的影响,提出了打击任意形状目标的命中概率计算模型。以慢速移动目标——舰船为例进行了仿真分析,结果表明提出的命中概率评估方法能够有效融合多源信息,评估结论符合工程实际。     

Impact time control using biased proportional navigation for missiles with varying velocity

A feasible guidance scheme with impact time constraint is proposed for attacking a stationary target by missiles with time-varying velocity. The main idea is to replace the constant velocity with the future mean velocity; therefore, the existing time-to-go estimation algorithm of the proportional navigation guidance law can be improved to adapt to varying conditions. In order to obtain the prediction of the velocity profile, the velocity differential equation to the downrange is derived, which can be numerically integrated between the current downrange and the target position by the on-board computer. Then, a third-order polynomial is introduced to fit the velocity profile in order to calculate the future mean velocity. At the beginning of each guidance loop, the future mean velocity is predicted and the time-to-go information is updated, based on which a novel biased proportional navigation guidance law is established to achieve the impact time constraint. Finally, numerical simulation results verified the effectiveness of the time-to-go estimation algorithm and the proposed law.     

基于目标加速度方向观测的微分对策制导律

针对延迟信息条件下的机动目标拦截问题,研究了一种考虑目标加速度方向观测的微分对策制导律。首先,针对引入目标方向观测信息末制导博弈问题,建立了微分对策数学模型。随后,利用状态依赖黎卡提方程求解微分对策问题,得到包含无延迟目标机动项的微分对策制导律,可以更为有效地拦截机动目标。最后,在延迟信息条件下,利用目标加速度方向观测的方法补偿延迟的目标加速度,再将补偿后的目标加速度信息取代无延迟的目标加速度,得到延迟信息条件下考虑目标加速度方向观测的微分对策制导律。仿真结果表明,新的制导律可以在延迟信息条件下有效地拦截机动目标。     

Heuristics of node selection criteria to assess robustness of world airport network

The world airport network (WAN) is one of the networked infrastructures that shape today's economic and social activity,so its resilience against incidents affecting the WAN is an important problem.In this paper,the robustness of air route networks is extended by defining and testing several heuristics to define selection criteria to detect the critical nodes of the WAN.In addition to heuristics based on genetic algorithms and simulated annealing,custom heuristics based on node damage and node betweenness are defined.The most effective heuristic is a multiattack heuristic combining both custom heuristics.Results obtained are of importance not only for advance in the understanding of the structure of complex networks,but also for critical node detection.     

统一系统载波捕获方法研究

介绍了现代统一系统中载波频率快速捕获的几种方法,并提出了统一系统载波快速捕获的一种算法。最后,通过对几种不同方法的计算时间与识别精度的比较,验证了该算法的高效性。     

一种基于自动相关信息四维运算的飞行间隔算法设计与实现

本文介绍了无人机（UAV：UnmannedAerialVehicle）航路规划的分层模式，提出了实时航路规划中四维接近算法，对UAV与静态和动态目标的接近距离进行了分析计算，为航路规划及时提供飞行过程中的危险接近信息，并进行了数字仿真。数字仿真表明：该算法具有较高的运算速度和较好预测精度，可快速提供UAV与周围静态和动...     

Optimal guidance against active defense ballistic missiles via differential game strategies

The optimal guidance problem for an interceptor against a ballistic missile with active defense is investigated in this paper. A class of optimal guidance schemes are proposed based on linear quadratic differential game method and numerical solution of Riccati differential equation. By choosing proper parameters, the proposed guidance schemes are able to drive the interceptor to the target and away from the defender simultaneously. Additionally, fuel cost, control saturation, chattering phenomenon and parameters selection were taken into account. Satisfaction of the proposed guidance schemes of the saddle point condition is proven theoretically. Finally, nonlinear numerical examples are included to demonstrate the effectiveness and performance of the developed guidance approaches. Comparison of control performance between different guidance schemes are presented and analysis.     

On early cognitive mapping

In this paper we examine the nature of theearly cognitive map – the beginnings of acognitive map formed from one's earlyimpressions of the environment one is in. Twodistinct paradigms have emerged from ourstudies of what information is initially identified in a cognitive map. The first, which weterm a space-based approach, emphasises makingexplicit the spatial extent of the currentlocal environment. The second emphasises makingexplicit the relationships between objects inthe local environment and we call this anobject-based approach. For both paradigms weexamine the psychological literature to findsupport for the approach and the roboticists'attempts at implementing the idea. We arguethat a space-based approach is the moreappropriate way to compute an early cognitivemap. In particular, we find that Siegel andWhite's (1975) object-based hypothesis, whichstates that the developmental progression of acognitive map is from landmark to route tosurvey map, is not supported. The space-basedparadigm underpins our own work in this areaand we outline our own space-based theory forcomputing an early cognitive map.