高能硝胺发射药燃烧性能的研究

本文以密闭爆发器恒压法研究了400MP。以下高能硝胺发射药的燃烧特性以及各种硝胺、黑索近的含量、颗粒尺寸和活性或惰性粘结剂对硝胺燃烧特性的影响,并对高能硝胺发射药的燃烧特性进行了分析。实验结果表明:各种硝胺发射药一般都有燃速曲线二次转折的燃烧特性,通常的规律是由低压力指数到高压力指数,再返回到低压力指数,黑索近的含量和颗粒尺寸对高能硝胺发射药的燃烧特性有轻微的影响,而不影响燃逮曲线的转折。粘结剂能量越高,燃速跃交幅度降低,但并未将燃速转折消除或使转折压力移向高压。这种燃速跃变幅度与粘结剂能量的关系并不适合于含与粘结剂有一定互溶性的硝胺发射药。硝胺发射药特异燃烧性能的原因,尚有待进一步实验探索研究。     

硝胺火药燃速特性与热分解特性的相关性

通过对四类、三十几种配方的硝胺火药进行系统的密闭爆发器实验及差热分析，发现硝胺火药燃速压力曲线转折与火药的二次热分解特性紧密相关，由此可推断，火药燃烧时其受压表面热分解反应过程是决定火药燃速稳定的控制步骤，提出了一种新的密闭爆发器燃速压力曲线性质的分析方法，并提出用β值大小来表征火药的二次热分解相对强度，以便用来判断火药燃速压力曲线的转折性质。这些概念和方法对于分析硝胺火药燃速特性具有重要实用价值。     

基于燃烧产物的硝胺类发射药的燃速预估模型

针对探讨硝胺类发射药的燃速预估模型,在分析硝胺炸药在燃烧分解产物热分解规律的基础上,运用近年来提出的火药燃速预估方法,推导硝铵发射药的燃速公式及压力指数公式。编写硝铵发射药燃速计算软件。在0～400 MPa压力范围内,对硝胺类发射药的燃速进行理论预估,并对3种硝铵发射药的燃烧计算值与相应的试验数据进行比较。分析结果表明,本模型是可行的,适合硝铵发射药的燃速预估。     

低压下硝胺发射药燃烧性能研究

为了研究RDX和硝基胍(NGu)对硝胺发射药在低压下燃烧性能的影响,对六种RDX/NGu配比不同的硝胺发射药进行低压密闭爆发器静态燃烧实验,获得了在20~60MPa压力范围内硝胺发射药的燃烧试验数据。结果发现:硝胺发射药在测试压力范围内有燃速压力曲线转折现象,并且NGu对低压下硝胺发射药燃烧规律有很好的调节作用。     

高压力指数发射药应用研究

叙述了燃速和燃速压力指数的概念，分析了各种因素对燃速压力指数的影响．由实验发现，不含硝胺的常规发射药（例如ＮＡＣＯ发射药）也有高压力指数现象，且这些发射药在数十年应用中未发现有异常现象．内弹道计算指出：燃速压力指数为１．１～１．２的发射药能获得合理的弹道性能，但初始弹道诸元对弹道性能的影响较敏感．因此，具有较高压力指数（１．１～１．２）的发射药可广泛地应用到火炮中去．     

低温感硝胺发射药混合装药的应用研究

从低温感发射药的基本原理出发 ,对低温感硝胺发射药在中大口径火炮上的应用试验进行了分析研究 .通过对硝胺发射药燃烧特性的测试 ,发现硝胺发射药的燃速压力曲线几乎是一条直线 ;由落锤冲击实验 ,认为硝胺发射药的低温力学性能还需进一步改善 ;根据弹道试验所得到的低温感硝胺发射药的初速和膛压结果 ,以及对试验火炮的烧蚀结果 ,证明了低温感硝胺发射药可作为中大口径火炮装药的可行性     

含FOX-12硝胺发射药的燃烧特性

采用DSC-TG、密闭爆发器、中止燃烧试验装置,研究了含N-脒基脲二硝酰胺盐(FOX-12)的硝胺发射药的热分解和燃烧特性。结果表明:该硝胺发射药中的NC-NG体系和FOX-12一起开始分解,加入FOX-12使硝胺发射药的燃速压力指数降低,其值小于1,随着FOX-12含量的增加,硝胺发射药的压力指数在低压段(10～20 MPa)降低幅度大于中高压段(40～240 MPa)的幅度。     

多基发射药燃烧性能的调节与优化

介绍了近来提出的多基发射药燃烧模型，利用其计算方法计算了多基发射药的化学组成对燃烧性能的影响；从化学结构和化学反应的层次分析了硝胺发射药燃速－压力曲线转折和某一压力范围内压力指数大于１的原因；从化学组成的角度出发提出了多基发射药燃烧性能优化设计的一些基本原则。     

硝胺单元推进剂燃速的理论计算

在火炸药燃速预估模型的基础上，分析了硝胺单质炸药的热分解特征，提出了硝胺单元推进剂燃烧初期热分解机理的有关假说，并将气相分解产物分类为氧化剂、还原剂、可裂解自由基和惰性基团，进而提出了硝胺单元推进剂燃速和压力指数公式．运用该公式可从化学结构出发计算硝胺单质炸药的燃速和压力指数．通过十种不同类型硝胺单元推进剂燃速的实际计算表明，理论值与实测值十分一致．由此讨论了影响硝胺单质炸药燃速与燃速压力指数的化学结构因素．     

发射药药型结构对燃速测试结果的影响

为了研究药型结构对发射药燃速测试结果的影响,以高能硝胺发射药为研究对象,采用密闭爆发器燃烧实验和数据处理的分析方法,研究了4种药型及其不同内孔长径比发射药的燃速特性及其变化规律;采用中止燃烧实验研究了发射药内孔长径比对侵蚀燃烧的影响,并与太根发射药对比研究了燃速特性对侵蚀燃烧的影响关系。结果表明,多孔药的燃速压力指数明显小于单孔药,在内孔长径比相同的条件下,随着发射药内孔数量的增加,正比式燃速系数减小,燃速压力指数减小;在药型相同的条件下,随着内孔长径比增大,发射药侵蚀燃烧现象加剧,正比式燃速系数增大,燃速压力指数减小;燃速较高的发射药,侵蚀燃烧现象对燃速参数测试结果的影响更大。     

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.     

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.     

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 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.