某多体系统的固有振动

用传递矩阵法，求得了弹性梁两端分别与两个任意形状刚体固结的多体系统的固有振动的频率方程和振型函数的精确解析式。     

航空发动机转子支承系统刚度计算中的几个问题

从计算航空发动机转子系统动力特性的需要出发, 讨论了发动机中支承机匣系统、弹性支承、轴承支承等典型支承结构的径向刚度计算中的几个问题, 并准确计算得到了某支承机匣及弹性环式弹支的径向刚度.     

爆炸荷载作用下柔性动边界拱的动力响应分析

实际工程中的拱结构并不是采用固支或简支等理想刚性支承，而是具有弹性支承、阻尼支承等柔性动边界。文中建立了具有动边界拱的力学模型，基于大变形动力微分方程并利用有限差分方法，研究分析了动边界拱在爆炸荷载作用下弹塑性动力响应。研究表明，柔性动边界对拱结构工作性能产生很大的影响，竖向弹性支承能够使短作用时间爆炸荷载下拱的内力峰值减小，并且使到达峰值的时间增加，阻尼支承能同时使结构的内力和位移衰减，因此可以利用柔性支承来提高结构的抗力。     

大型旋转飞行器在非线性不对称支承条件的发射特性分析

以大型，远程旋转火箭为例，将飞行器仿真为具有多个非线性，不对称支承的Euler-Bernoulli旋转梁，根据有限元方法和Hamilton原理建立飞行器的运行控制方程，利用分段线性化方法近似弹性支承的非线性刚度，数值仿真并分析了推力偏心，质量偏心，结构柔性和支承非线性等因素对飞行器动力响应的影响，可望为新一代，高精度旋转飞行器的设计提计提供理论参考。     

有任意个集中质量的转管炮的固有振动

建立了带有任意个集中质量的分布质量炮管的转管炮系统横向自由振动运动学模型；求得了该系统固有振动频率和振型函数的精确解析式；阐明了转管炮的动频和相应振型与对应静频和相应振型及转动角速度之间的精确关系。最后给出了电算结果，讨论了集中质量的大小和位置对系统频率的影响，指出了转动角速度对系统动频有很大的影响，指出了转动角速度对系统动频有很大影响，提出了减小转管炮系统射弹散布的技术途径。本研究结果为提高转管     

自行火炮振动特性的计算

准确计算自行火炮的振动特性是发射动力学研究的重要内容．将自行火炮处理为由多个刚体、集中质量、弹性梁按一定方式铰接而成的刚弹耦合多体系统，建立了自行火炮的动力学模型，用多体系统传递矩阵法计算了其振动特性．计算结果与试验结果吻合较好．文中的方法可方便地推广到其它武器系统和各种机械多体系统．     

多体火炮系统的固有振动特性-多体系统动力学的传递矩阵法

导得了任意刚体作线性振动的场传递矩阵。建立了多体系统动力学的传递矩阵方法，并将其应用于一般多体火炮系统固有振动的研究，建立了相应的多体火炮系统振动的传递方程和传递矩阵。导得了有关多体火炮系统振动的频率方程和振型函数的解析式。     

带有集中质量的分布质量弹性转动横振精确解

求得了带有集中质量的分布质量弹性转轴系统横向自由振动的频率方程和振型函数的精确解析表达式，及其与不转动轴系统自由振动的频率方程和振型函数及转动角速度之间的精确解析关系     

某车载炮系统振动特性研究

车载炮系统的射击精度与其自身的结构动态特性密切相关。因而很有必要研究火炮结构的振动特性对火炮射击精度的影响。利用多体系统传递矩阵法将车载炮系统处理成由多个刚体、集中质量、空间弹性梁并按一定的方式铰接而成的刚弹耦合系统。利用传递矩阵法并依据确定的传递方向，可将车载炮系统由下到上依次划分为：车轮、车体、除去起落部分的回转部分、除去后坐部分的起落部分、炮闩、身管和炮口制退器。每个部件可按照自然属性视为刚体、弹性梁和集中质量。建立了车载炮系统的动力学模型，利用Matlab编程计算并得到了某车载炮系统的振动特性。     

刚性支承外伸火箭的横向振动

本文提供一种计算刚性支承火箭的横向振动特性的简单方法——传递矩阵法。其中考虑了剪切和转动惯量的影响;给出了处理支承点处剪力不连续的方法,并且对一个具体实例进行了计算。     

Stability of the Third Generation Intensifier under Illumination

The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.     

Passive Acoustic Radar for Detecting Supersonic Cruise Missile

A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.     

Super-resolution Restoration of Remote-sensing Images

A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint （MPMAP） combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that superresolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function （PSF） value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.     

Design and Simulation of TF and TA Controller for Missile

A nonlinear terrain following(TF) and terrain avoidance(TA) controller is proposed for missile control systems. Based on classical TF algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from digital elevation map (DEM) for TF control is discussed in order to save store space. A TA algorithm is proposed by using bank-to-turn technique. The block control model, which is suitable for backstepping design, is given for nonlinear model of missile. Making full use of the characteristics of the system and combining block control principle and backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors are converged to a neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the missile model are presented to demonstrate the effectiveness of the proposed control law.     

Design and Analysis of Test Schemes of Static Postponing Time on Shrapnels Used to Riot Control

The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures,the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done,feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.     

Design of Non-fragile Satisfactory Estimator for Linear Continuous Perturbed Stochastic Systems

The design problem of non-fragile estimator is addressed for a class of perturbed linear continuous systems. The perturbations occur on the plant and estimator parameters. The estimator designed should force the error system to achieve the desired decay rate and force the steady error variance less than the specified upper bound irrdevancy of the admissible plant perturbations and estimator perturbations. Consistency problem of the decay rate with the variance upper bound is first considered via linear matrix inequality （LMI） approach. The solution of the estimator parameter under specifications to be consistent is then discussed. The consistency condition of specifications and estimator parameter solution are transformed to feasible or minimum problems subject to a set of LMI respectively. The method is illustrated by a numerical example.     

An Improved Scene-based Nonuniformity Correction Algorithm for Infrared Focal Plane Arrays Using Neural Networks

The improved scene-based adaptive nonuniformity correction （NUC） algorithms using a neural network （NNT） approach for infrared image sequences are presented and analyzed. The retlna-like neural networks using steepest descent model was the first proposed infrared focal plane arrays （IRFPA） nonuniformity compensation method, which can perform parameter estimation of the sensors over time on a frame by frame basis. To increase the strength and the robustness of the NNT algorithm and to avoid the presence of ghosting artifacts, some optimization techniques, including momentum term, regularization factor and adaptive learning rate, were executed in the parameter learning process. In this paper, the local median filtering result of Xij （ n ） is proposed as an alternative value of desired network output of neuron Xij （ n ）, denoted as Tij （ n ）, which is the local spatial average of Xij （ n ） in traditional NNT methods. Noticeably, the NUC algorithm is inter-frame adaptive in nature and does not rely on any statistical assumptions on the scene data in the image sequence. Applications of this algorithm to the simulated video sequences and real infrared data taken with PV320 show that the correction results of image sequence are better than that of using original NNT approach, especially for the short-time image sequences （several hundred frames） subjected to the dense impulse noises with a number of dead or saturated pixels.     

Piecewise Filter of Infrared Image Based on Moment Theory

The disadvantages of IR images mostly include high noise, blurry edge and so on. The characteristics make the existent smoothing methods ineffective in preserving edge, To solve this problem, a piecewise moment filter （PMF） is put forward. By using moment and piecewise linear theory, the filter can preserve edge. Based on the statistical model of random noise, a related-coefficient method is presented to estimate the variance of noise. The edge region and model are then detected by the estimated variance. The expectation of first-order derivatives is used in getting the reliable offset of edge. At last, a fast moment filter of double-stair edge model is used to gain the piecewise smoothing results and reduce the calculation. The experimental result shows that the new method has a better capability than other methods in suppressing noise and preserving edge.     

Bistatic Sonar Localization Based on Best Linear Unbiased Estimation

A best linear unbiased estimation （BLUE） algorithm for bistatic sonar localization is proposed. The Cramer-Rao bound for bistatic Sonar and the geometrical dilution of precision （GDOP） in different conditions are given. The simulation results show that the location accuracy of BLUE algorithm is higher than the weighted least square method.     

Research on Gear-broken Fault Diagnosis in a Tank Gearbox

A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank, extracting the envelope of vibration signal by Hilbert transformation amplitude demodulation method, and zooming the low-frequency band to envelope signal.