铝粉粒径对闪光剂辐射强度的影响

研究了铝粉粒径对闪光剂辐射强度的影响.利用粒径影响因子对闪光剂燃烧产物中凝聚相粒子的发射率进行了修正.结合铝粉燃烧模型、凝聚相产物发射率和闪光剂爆燃闪光辐射模型,提出了铝粉粒径和闪光剂辐射强度的关系.理论分析得出了闪光剂配方中铝粉粒径越小,其闪光辐射强度越高.测试了由不同粒径铝粉和高氯酸钾组成的二元闪光剂配方(质量比为50/50)及由不同粒径铝粉、高氯酸钾和3%环氧树脂组成的三元闪光剂配方(质量比为50/50/3)的闪光辐射强度,验证了这一结论的正确性.     

强闪光烟火药过载能力的实验研究

采用大落锤冲击装置模拟研究了强闪光烟火药的过载能力。实验结果表明:强闪光烟火药在装药密度为1.9×103kg.m-3,实验加载应力653 MPa,装药长度为40 mm时承受的过载为8.59×105g(g=10 m.s-2);在加载应力小于653 MPa范围内,强过载产生的热点不能引燃该强闪光药柱。原因可能是(1)强闪光烟火药中氧化剂的热分解温度和可燃物的着火点很高,难以诱发反应;(2)装药质量得到很大改善,热点产生源减少;(3)压药过程使得KC lO4和铝粉的接触面积增大,热点源产生的热量可以通过金属颗粒较迅速向其周围传递,以致热点熄灭。     

基于波形诱骗的末敏弹毫米波有源干扰研究

根据末敏弹毫米波交流辐射计探测金属目标时弹目交会特点和信号处理电路特性,提出了一种基于波形诱骗的毫米波有源干扰新方法。分析并建立了辐射计探测干扰源信号时的天线温度模型,与探测地面金属目标相比,天线温度信号脉宽明显展宽,幅度保持恒定。该信号经视频放大器低频截止作用后,使输入的等幅宽时信号发生频率失真,输出具有正、负脉冲形式的波形分裂信号,其中负脉冲部分可以模拟探测地面金属目标的输出信号。实验结果验证了设计方法的正确性和有效性,为毫米波末敏弹有源干扰提供了一种可行的方法。     

水声引信双门控制自调周期抗邻弹干扰方法

多枚深弹齐射时,在有效探测范围内,可能会出现邻弹干扰,引起引信误动。解决方法有多普勒频偏法和编码法:多普勒频偏法只能确定回波的存在,不能区分类别;编码方法的信号脉宽必须大于脉冲展宽,会增大探测盲区。受蝙蝠双耳对回波敏感的启发,设计一个双门控制信号,以降低近距离体积混响干扰和避免邻弹干扰,控制门内允许接收信号。若两个门内都有信号,则判断该信号为自身发射信号的回波;若第一个控制门内有信号,第二个控制门内无信号,由于多次探测发射信号周期是按规律变化,所以可判断该信号为非自身发射信号,排除邻弹干扰。实验表明,双门控制自调周期信号简单,使深弹水声引信对邻弹引信发射信号回波不敏感,且提高了测距准确率。     

目标、背景和干扰的视景仿真与红外热图像模拟

文中介绍一种红外图像的仿真方法,通过建模软件CREATER建立目标、背景和红外干扰弹的三维模型,构建一个三维场景.根据运动学和动力学方程,使目标和干扰按照各自的运动模式运动,实时地进行目标、背景和红外干扰弹的可见光视景仿真;分析目标、背景和干扰的红外辐射特性,用红外计算模块计算出传感器路径上大气衰减,将经过大气衰减和传感器化的目标辐射强度量化为灰度图,赋予场景中的三维实体,通过视景仿真软件VEGA模拟生成红外导引头探测到的含背景、红外干扰弹的目标红外热图像的量化灰度图.     

弹载电子干扰机作战效能仿真评估

为评估弹载干扰机的作战效能,在干扰评估准则的基础上,建立干扰、探测模型,通过分析反导系统于目标导弹之间的关系,提出最小干扰距离指标,并对几种典型反导武器系统的探测雷达进行干扰效果仿真计算,分析其在最小干扰距离指标下的干信比,得出弹载干扰机的作战效能。该研究对现代高技术战争条件下导弹攻防对抗具有实际意义和应用价值。     

红外干扰弹干扰性能测试系统

为了在红外干扰弹交付过程中评价干扰效果,设计了红外干扰弹干扰性能测试系统。系统由目标、非制冷热象仪、配有专用视频采集卡的笔记本电脑、打印机等硬件组成。系统对热象仪输出的模拟视频信号进行采集和录制,经计算机程序转换为有序的图像系列,再进行分割处理、初步比较和精确计算,输出烟幕的面积、形成时间和持续时间,对烟幕的干扰效果进行评价。实践证明,该系统能较好地测试红外干扰弹干扰效果,解决了红外干扰装备在生产、验收过程中成品干扰性能测试问题。     

弹载雷达与目标干扰对抗认知波形优化

电子战环境中,被探测目标具有释放干扰躲避雷达探测的能力。弹载雷达不仅要在杂波环境中优化发射信号以提高波形抑制杂波的能力,同时还应考虑雷达与目标相互间的博弈。本文建立弹载雷达与拥有干扰能力的目标间对抗时的信号模型,基于最小均方误差准则二次分配雷达发射波形能量,优化设计雷达发射波形,初步解决了杂波背景中弹载雷达受到目标施放干扰而导致的雷达探测性能降低的问题。仿真结果表明,二次优化对噪声、杂波和干扰影响的抑制效果为单次优化的3倍。     

未爆炸弹的磁梯度探测方法

针对常规的未爆炸弹勘探方法是以测量磁总场为主,部分弱磁异常很难发现的问题,提出了未爆炸弹的磁梯度探测方法。该方法以球体和有限长圆柱体为地下未爆炸弹的磁性模型,采用磁梯度探测技术和小波多尺度分解数据处理方法,探讨未爆炸弹的磁梯度探测技术的可行性。通过5个具有不同磁性、不同埋设方位的未爆炸弹的物理模拟,其实验结果表明:该方法将大大提高弱磁异常有效信息的分辨率,具有明显的优势。     

激光引信双向驱动单发单收大视场探测技术研究

由于受系统功耗和空间的限制,常规弹药激光引信无法采取多个激光器和多个激光接收器实现多发多收,同时传统的激光大视场探测方式无法满足小型化、结构简单的需求。提出一种新型的双向驱动单发单收大视场探测方案,建立弹目交汇捕获率数学模型,分析了不同弹目距离以及不同转速下目标捕获率。并针对系统电磁干扰影响因素,采用多种方法复合屏蔽电磁信号对回波信号的干扰,加工制作了原理样机,进行了抗电磁干扰实验以及不同距离动态旋转目标探测实验,结果表明本方案能够有效屏蔽系统电磁干扰,在转速50 000 r/ min 时能保证距离为8 m 的目标可靠捕获,使大视场全向探测激光引信在常规弹药上的应用成为可能。     

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.     

Expert Systems Aimed at General Design of Projectiles

Expert systems aimed at the general design of projectiles can implement a series of intelligent designs, such as the design of HE shell, the scheme expounded and proved, the emulation analysis and calculation, etc. Aiming at the product design feature, the expert system adopts the object-oriented knowledge representation and all kinds of inference control engines to describe and reason the relevant knowledge regarding the product through the microcomputer. It embodies the foundation of emulation analysis and simulated manufacturing of the shell. It makes use of the method that knowledge expression is combined with condition of inference to carry out the overall design and emulation and reference.The paper gives the ways through which the functions can be achieved, gives the modularization of reference and the design methods of systematization, puts forward the method of knowledge expression and working interface, and supplies a platform for similar products of the shell category that can be quickly designed.     

Three-dimensional Numerical Simulation of Combustion Field in the Combustion Chamber

In order to study the effect of rotation on the combustion in the underwater vehicle, a two-phase turbulent combustion process is described with Reynolds stress turbulence model, eddy-dissipation turbulent combustion model, P-1 radiation model and particle tracking model of liquid. The flow in the rotating combustion chamber is simulated at two different working speeds, 0 r/min and 1 000 r/min by Fluent software. The temperature, gas velocity, static pressure of wall and fuel concentration are computed and compared. The results show that the combustion in rotating combustor is faster and more effective.     

Software Communication Architecture Implementation and Its Waveform Application

This paper attempts to do a research on the development of software defined radio（SDR） based on software communication architecture（SCA）. Firstly, SCA is studied and a whole reference model of SCA3.0 core framework （CF） is realized; Secondly, an application-specific FM3TR waveform is implemented on the platform of common software based on the reference model; Thirdly, from the point of view of real-time performance and software reuse, tests and validations are made on the above realized CF reference model and FM3TR waveform. As a result, the SCA-compliant SDR has favorable interoperability and software portability and can satisfy the real-time performance requirements which are not too rigorous.     

Parameter Identification for the Valve Control Cylinder System of a Hydraulic Manipulator

In mechanical, hydraulic and electronic systems, the determination of system parameters is often challenging because liquid parameters often change significantly, due to variations in working and environmental conditions. Therefore, it is of significant practical importance to identify those parameters through experimental procedures. A systematic approach to identifying parameters in the valve controlling cylinder system of hydraulic manipulators is provided. It first derives the transfer function of the system, and then uses P control of PID control to predict system parameters. The predicted parameters are further validated using PID control. The prediction through simulation using MatLab language is utilized, which agrees well with experimental results.     

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.