某机载探测系统自主回收技术的实现

针对某机载探测系统探头回收自动化程度低的问题，提出了在无需操作员干预情况下实现探头自主回收的技术方法。采用了先进的控制算法，将缆位角与探头、缆长进行结合并引入了绞车控制系统，使绞车对探头的回收速度及缆长可进行实时调整，并给出了3种不同缆位角摆动条件下缆长与探头回收速度的控制曲线关系。研发了自主回收装置，设计了能够实现自主回收功能的探头回收机构。实验验证表明：在无需人为干预的条件下，在缆位控制系统及自主回收机构的配合下，系统实现了对探头快速、安全的回收。     

高超声速飞行器再入段LQR自抗扰控制方法设计

针对高超声速飞行器(HSV)再入过程中强非线性、强耦合、气动参数变化剧烈的不确定性的特点，提出一种基于线性二次型调节器(LQR)和自抗扰控制(ADRC)的高超声速飞行器再入段的姿态控制方法。首先，建立高超声速飞行器再入段线性化模型，并采用LQR方法完成了状态反馈控制律设计。然后，结合自抗扰控制技术，设计了扩张状态观测器(ESO)对系统的模型不确定性和外部干扰进行补偿，大幅增强了系统的扰动抑制能力。最后，将得到的高超声速飞行器再入段LQR自抗扰姿态控制器(LQRADRC)应用于高超声速飞行器六自由度仿真，仿真结果表明本文所提出的控制方法能够快速、精确地跟踪角位置指令，并且对系统不确定性具有强鲁棒性。     

一种应用于超小型无人机的新型定高传感器

使用美国ICSENSOR公司的压阻硅式绝压传感器，对静压进行测量，并设计出适合超小型无人机使用的新型定高传感器，这种定高传感器具有灵敏度高，重量轻，单电源供电，板式结构。可靠性高，重复性好的特点，填补了应用于超小型无人机的定高传感器产品的空白。     

电连接器接点焊接工艺研究

针对航天产品电连接器接点焊点与引线断裂失效问题,分析了焊接过程中助焊剂、焊料、焊接工具和防护套等对接点焊接质量的影响。结合实践经验,提出相关工作参数和材料的选取原则,确定了生产中焊接技术的质量控制点。     

Almost instant time inference for hybrid partially dynamic Bayesian networks

A Bayesian network (BN) is a compact representation for probabilistic models and inference. They have been used successfully for many military and civilian applications. It is well known that, in general, the inference algorithms to compute the exact a posterior probability of a target node given observed evidence are either computationally infeasible for dense networks or impossible for general hybrid networks. In those cases, one either computes the approximate results using stochastic simulation methods or approximates the model using discretization or a Gaussian mixture model before applying an exact inference algorithm. This paper combines the concept of simulation and model approximation to propose an efficient algorithm for those cases. The main contribution here is a unified treatment of arbitrary (nonlinear non-Gaussian) hybrid (discrete and continuous) BN inference having both computation and accuracy scalability. The key idea is to precompile the high-dimensional hybrid distribution using a hypercube representation and apply it for both static and dynamic BN inference. Since the inference process essentially becomes a combination of table look-up and some simple operations, the method is shown to be extremely efficient. It can also he scaled to achieve any desirable accuracy given sufficient preprocessing time and memory for the cases where exact inference is not possible     

Performance evaluation for MAP state estimate fusion

This paper presents a quantitative performance evaluation method for the maximum a posteriori (MAP) state estimate fusion algorithm. Under ideal conditions where data association is assumed to be perfect, it has been shown that the MAP or best linear unbiased estimate (BLUE) fusion formula provides the best linear minimum mean squared estimate (LMMSE) given local estimates under the linear Gaussian assumption for a static system. However, for a dynamic system where fusion is recursively performed by the fusion center on local estimates generated from local measurements, it is not obvious how the MAP algorithm will perform. In the past, several performance evaluation methods have been proposed for various fusion algorithms, including simple convex combination, cross-covariance combination, information matrix, and MAP fusion. However, not much has been done to quantify the steady state behavior of these fusion methods for a dynamic system. The goal of this work is to present analytical fusion performance results for MAP state estimate fusion without extensive Monte Carlo simulations, using an approach developed for steady state performance evaluation for track fusion. Two different communication strategies are considered: fusion with and without feedback to the sensors. Analytic curves for the steady state performance of the fusion algorithm for various communication patterns are presented under different operating conditions.     

非线性四阶微分方程两点边值问题解的存在唯一性

讨论了非线性四阶微分方程y(4)=f(x,y,y',y',y')的两点边值问题解的存在唯一性。其中,函数f在[a,b]×R4上连续,且满足Lipschitz条件。     

风量与风机的安全运行

本文阐明了离心式通风机在通风除尘(或排毒净化)系统中的作用,以及离心式通风机产生风压.风量的工作工程,从而引出风机的性能参数风量L、风压P、功率N、效率η等.文章突出地论述了风量对风压、功率、效率的影响;详尽地分析了离心式通风机的性能曲线,特别是N—L曲线;根据性能曲线分析得知,风量L为零(L=0)时,风消耗的功率N最小.从而得出结论;系统中的离心式通风机必须是在关闭状态下启动,以确保通风机的安全运行.     

加入WTO对中国航空货物运输的影响分析

针对中国加入WTO对航空货物运输的影响，从溢出效应、竞争、辅助市场的开放、市场准入、管理、WTO规则和机制6个方面进行了分析。强调要全面和发展地看待WTO给航空货物运输带来的影响，以及要更加注重掌握WTO的规则和机制，才能更好地理解WTO对航空货物运输企业经营环境和约束条件的影响。     

基于粒子群优化算法的不完全数据的处理

不完全信息下的数据挖掘是一个困难的问题，但它在实际决策中是不可避免的。在介绍几种处理方法的基础上，提出了基于粒子群优化算法的处理方法。对适应函数进行了讨论，实例表明该方法比较有效。