黑索今爆轰临界厚度的神经网络预测研究

采用楔形装药,测量了粒径范围在1~2μm(平均粒径为1.5μm)的超细黑索今(RDX)在不同密度、粒度与不同粘结剂含量下的爆轰临界厚度。以密度、粒度与粘结剂含量作为输入元,RDX爆轰临界厚度作为输出元建立了RDX爆轰临界厚度的E lman神经网络预测模型。以实验数据对模型进行训练,采用达到误差要求的模型对不同密度、粒度与粘结剂含量下的RDX爆轰临界厚度进行预测。预测结果显示:3个影响因素对临界直径的影响规律与文献[9-11]报道相同,说明神经网络用于RDX爆轰临界厚度预测是可行的。     

基于神经网络的HMX爆轰临界厚度预测研究

为实现HMX爆轰临界厚度的神经网络预测,采用长通道楔形槽内直接压药的装药方式,测量了HMX在不同密度、粒度与不同粘接剂含量下的爆轰临界厚度.以此3个因素作为输入节点、爆轰临界厚度作为输出节点建立了HMX爆轰临界厚度的BP神经网络预测模型.通过试验数据对神经网络预测模型进行训练使之达到误差要求,采用训练好的预测模型对不同密度、粒度与粘接剂含量的HMX爆轰临界厚度进行预测.预测结果表明,HMX的粒度、压药密度、粘接剂含量对爆轰临界厚度的影响与相关文献报道相同,说明神经网络可以用于HMX爆轰临界厚度的预测.     

超细钝感HMX小尺寸沟槽装药爆轰波传播临界特性研究

选用粒径为587.3 nm的HMX,以LZ12为基板材料设计不同沟槽尺寸,采用精密压装法装药,对超细化钝感HMX在小尺寸沟槽装药条件下的爆轰波传播临界特性进行了研究。结果表明,在设计装药密度为1.77 g.cm-3时,超细化钝感HMX沟槽装药直线传播的临界尺寸约为0.4 mm×0.4 mm,极限尺寸为1.2 mm×1.2 mm,拐直角传播的临界尺寸为0.5 mm×0.5 mm。     

RDX炸药对传爆药临界直径的数值模拟

为了研究炸药对爆轰临界直径的影响,建立了楔形和圆柱形装药的物理模型,采用LS-DYNA2D程序模拟了爆轰波传播过程,得到楔形和圆柱形装药的临界直径.模拟结果与文献基本符合,进一步说明了利用LS-DYNA程序对小尺寸装药爆轰波传播的数值模拟是可行的.     

装药条件对飞片雷管爆轰性能的影响

为了研究飞片式无起爆药电雷管的爆轰性能,分析了雷管起爆机理以及爆轰传递过程,通过铅板穿孔试验,研究了装药密度、装药药量对雷管轴向输出的影响。结果表明:输出装药密度越大,8#飞片式无起爆药雷管的输出威力越大,合适的输出装药药量为0.33g;第2中间装药压药密度的最佳范围为1.3~1.4g.cm-3。     

微通道用挤注型传爆药研究

针对沟槽式微通道传爆序列,设计了挤注排气装药技术,采用HMX/CL-20基挤注固化型炸药,研究了其直线沟槽装药传爆性能,确定了较为理想的装药配方。结果表明,该工艺用于小尺寸传爆沟槽装药可行,药体成型平整致密,沟槽装药密度达1.37g·cm-3;理想配方的沟槽装药传爆可靠稳定,截面尺寸1.0mm×1.0mm与0.8mm×0.8mm沟槽通道内平均爆速分别为7 138m.s-1与6979 m·s-1,临界传爆尺寸约0.5mm×0.5mm。     

一种测量工业炸药临界直径和临界厚度的连续电阻丝探针法

为了定量判定工业炸药的临界直径和临界厚度,自行研制了一种可连续测量爆轰波和冲击波速度的电阻丝探针,并以粉状铵油炸药(ANFO)为测试对象,设计了无约束锥形和半约束楔形两种装药形式,利用单发实验便可分别测得粉状ANFO炸药在两种约束条件下的爆速变化曲线,从而计算出相应的临界直径和临界厚度。结果表明:粉状ANFO炸药的临界直径随炸药密度的增大而增大;所测炸药在0.67 g·cm~(-3)密度下无约束条件时的平均临界直径为16.75 mm,底部钢板约束时的平均临界厚度为7.06 mm,两者的比值为2.37。     

小尺寸传爆药爆轰反应区厚度研究

利用双灵敏度VISAR测试了小尺寸传爆药装药的爆轰反应区厚度.试验采用JO-9C和HNS传爆药,装药直径为6mm和4mm,约束条件为45~#钢和有机玻璃,利用4μm厚的铝箔作为粒子速度载体,得到了装药与LiF窗口界面粒子速度的全过程.结果表明:JO-9C小尺寸装药的反应时间约为40ns,相应的反应区厚度约为0.22mm和0.23mm;HNS小尺寸装药的反应时间约为120ns,相应的反应区厚度约为0.60mm.     

多点起爆网络装药及性能

为了研究多点起爆网络装药对爆轰波输出同步性及起爆能力的影响,以超细奥克托今(HMX)为主体炸药,硝化棉(NC)为粘结剂,(HMX/NC=95∶5)为沟槽传爆药装药,设计了一种3点同步刚性起爆网络,理论分析和测定了起爆网络在不同装药密度下的同步误差,对比试验了沟槽压装装药技术,对传爆药进行了表征,测试了起爆网络相关的爆轰性能,优化了起爆网络装药结构。结果表明,提高起爆网络装药密度能够增加起爆可靠性和降低同步误差,装药密度从1.17 g·cm~(-3)增加到1.47 g·cm~(-3),起爆网络的同步误差从300 ns降低到150 ns。以JH-2压装药柱作为输出端装药,超细HMX/NC传爆药作为沟槽装药,采用沟槽压装装药技术,可以使同步起爆网络的爆轰波输出同步性约为100 ns。     

低温下HMX混合炸药小尺寸传爆的可靠设计

通过采用精密压装装药技术,对以细颗粒 HMX 为主体的混合炸药在低温-40℃条件下的爆轰波传播特性进行了试验研究,确定了该炸药的爆轰波侧向三通传播的临界尺寸为 SP 0.999 =0.56mm2;采用方形沟槽装药时,可以设计沟槽尺寸在0.79mm×0.79mm～0.89mm×0.89mm 之间。研究结果表明,该炸药低温下爆轰波侧向三通传播的临界尺寸较小,可用于爆炸逻辑网络装药。     

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.