Table of Content

31 March 2001, Volume 22 Issue 1

Previous Issue    Next Issue

Paper

Analysis of the Structural Parameters of a Tank Gun

Wei Xiaoda, Zhou Changjun

2001, 22(1):  1-4.  doi:10.3969/j.issn.1000-1093.2001.01.001

Asbtract ( )   PDF (4397KB) ( )  

References | Related Articles | Metrics

Vibration of tank gun in the process of firing is one of the main factors that affect its fir?ing accuracy，especially the instantaneous angular motion and the instantaneous linear velocity at the point of gun muzzle when the projectile leaves the barrel bore. To increase the firing accuracy, empha?sis is laid on the design concepts of “mountting two symmetrically arranged recoil brakes” and “free re?coil before projectile leaves the barrel bore”, in order to decrease the interference forces and moments affecting the weapon system before projectile leaves the barrel. Method of dynamic analysis and calcu-lation is used to explain how structural paranmeters affect the firing accuracy a gun. lation is used to explain how structural para

A Study on the Method of Application of Boundary Conditions for the Finite Element Analysis of Cylinder Head Subjected to Mechanical Loads

Liao Ridong, Zuo Zhengxing, Zou Wensheng

2001, 22(1):  5-10.  doi:10.3969/j.issn.1000-1093.2001.01.002

Asbtract ( )   PDF (7167KB) ( )  

References | Related Articles | Metrics

Due to the presence of complicated boundary conditions，it is often difficult to apply an accurate finite element analysis on cylinder heads. The paper discusses different cases of cylinder blocks and bolts under simulation. Some conclusions useful for increasing the accuracy of analysis are summarized. Discrete errors of the model adopted are analyzed.

3一D Finite Element Analysis of the Temperature Field，Thermal Deformation and Stress of Pistons in Diesel Engines

Xue Mingde, Ding Hongwei, Wang Lihua

2001, 22(1):  11-14.  doi:10.3969/j.issn.1000-1093.2001.01.003

Asbtract ( )   PDF (5032KB) ( )  

References | Related Articles | Metrics

In this paper 3-D FEM analysis of the temperature field and heat transfer in the piston of a high-powered diesel engine is given applying the MARC software. The thermal deformation and stress fields are calculated as well. The results enable one to locate where and why failures might hap?pen and provide a reference to improve piston design.

Variable Structure Control for Sliding Mode of Tank Stabilizator Based on Optimization

Sun Changsheng, Chen Jie, Dou Lihua

2001, 22(1):  15-18.  doi:10.3969/j.issn.1000-1093.2001.01.004

Asbtract ( )   PDF (4008KB) ( )  

References | Related Articles | Metrics

The technique of variable structure control for sliding mode of tank stabilizator is stud?ied. The switching function is defined using optimazition，and the law of variable structure control is determined by reaching conditions. Simulation test is taken as a method of study. Thus a realistic new technique is provided for the design of tank stabilizators.

A Model for the Detection of Geomagnetism and Solar Direction for Use in Artillery Projectile Attitude Measurement

1：Huang Zheng ,Li Kejie；2：Jin Lianbao

2001, 22(1):  19-22.  doi:10.3969/j.issn.1000-1093.2001.01.005

Asbtract ( )   PDF (4247KB) ( )  

References | Related Articles | Metrics

For use in the attitude measurement of artillery projectiles, a strap-down type geomag?netism and solar direction sensor is made use of to decide the attitudinal data. A theoretical attitude measurement model is set up, referred to the respective directions of geomagnetism and the sun. Through detailed study and analysis ,the model and method of measurement given adapt well to cases of projectile attitude measurement in the environment of high g shoot and high rate of revolution.

Intelligent CAD in the Design of Automatic Mechanisms in Small Arms

Liu Changyi, Xu Cheng

2001, 22(1):  23-26.  doi:10.3969/j.issn.1000-1093.2001.01.006

Asbtract ( )   PDF (4754KB) ( )  

References | Related Articles | Metrics

Based on the features of automatic mechanisms in small arms the key components in the design of automatic weapons，the methods of comprehensive evaluation and decision making，rule- based reasoning and case-based design are synthesized in the prototype systems development of auto?matic mechanisms. The key problems to be covered in the automatic mechanism layout design CAD are studied and resolved.

Numerical Simulation of Two-Phase Flow of Bulk Liquid Traveling Charge

Lu Xin, Zhou Yanhuang, Yu Yonggang

2001, 22(1):  27-30.  doi:10.3969/j.issn.1000-1093.2001.01.007

Asbtract ( )   PDF (3942KB) ( )  

References | Related Articles | Metrics

Traveling charge can effectively increase the muzzle velocity of a projectile through im- pravement of the projectile-based pressure due to combustion of traveling liquid propellant. It can be used in existing weapon systems to reinforce power without changes in artillery structure. This paper reports firsthand results about bulk liquid traveling charge. A complete two-phase flow mathematical model of the interior ballistics of traveling charge is developed and numerically calculated adopting the MacCormack scheme. The pressure, gas velocity and particle velocity distribution curves the trav?eling charge are obtained and compared with those of conventional structure, p-t curve in the slope bore matches well with the experimental results，indicating that this model can reveal the fundamental laws of two-phase flow in the bore.

Aeroelastic Stability Conditions for Large L/D Ratio Rockets

Wang Liangming

2001, 22(1):  31-33.  doi:10.3969/j.issn.1000-1093.2001.01.008

Asbtract ( )   PDF (3043KB) ( )  

References | Related Articles | Metrics

Based on the coupled dynamic model for the spatial rotation and elastic vibration of a body，the aeroelastic stability of rockets in flight is studied by Laplace transform equations. Under the consideration of a first-order vibration mode，the static aeroelastic stability condition is obtained. According to the Hurwitz discriminance of stability, the dynamic stability conditions are derived and tlie diagram of dynamic stability is determined. The results are of great importance to the design of projectiles or rockets having large L/D ratios.

Simulation and Analysis of the Launching Dynamics of a Self-Propelled Gun

Min Jianping, Yang Guolai, Yang Bozhong, Chen Yunsheng

2001, 22(1):  34-36.  doi:10.3969/j.issn.1000-1093.2001.01.009

Asbtract ( )   PDF (3027KB) ( )  

References | Related Articles | Metrics

This paper is focused on the theory of parametric modeling for the dynamics of flexible multibody systems with applications on artillery dynamics simulation. Modeling theory and numerical method are proDed for the dynamic analysis of flexible multibody systems. Elastic deformation is de?scribed making use of the mode expansion method. An example of dynamic simulation for the self-pro?pelled gun with caterpillars is given to illustrate the application of the proposed method.

Penetration and Perforation of Ceramic/Aluminum Composite Targets by High-Speed Tungsten Alloy Sphere

Jiang Chunlan, Chen Fang, Li Ming, Ma Xiaoqing

2001, 22(1):  37-40.  doi:10.3969/j.issn.1000-1093.2001.01.010

Asbtract ( )   PDF (4972KB) ( )  

References | Related Articles | Metrics

Ballistic properties of tungsten alloy spheres penetrating normally through ceramic/alu- minum composite targets are investigated and analyzed. The mode of deformation and failure of the tungsten sphere and the target during penetration is explored. The ballistic limiting velocity of the target with different area density is measured. The process and mechanism with which a tungsten sphere penetrates ceramic/aluminum ana steel armor are studied and analyzed. It is useful in the de?sign of warhead and light-armors.

An Analysis of the Efficiency of Fuze-Warhead Coordination

1：Zhuang Zhihong, Liu Jianfeng；2: Li Lirong, Li Xuehong;

2001, 22(1):  41-44.  doi:10.3969/j.issn.1000-1093.2001.01.011

Asbtract ( )   PDF (4807KB) ( )  

References | Related Articles | Metrics

Based on an analysis of fuze-warhead coordination, evaluation of the efficiency of fuze- warhead coordination is taken as made up of two parts.the design efficiency and the bursting model efficiency. Their quantitative expressions are derived and their applications are discussed regarding the choice of fuze systems and the optimization of bursting models.

Structural Design and Time Analysis of Synchronous Explosive Circuit in a Rigid Surface

Wen Yuquan, Jiao Qingjie ,Li Guoxin ,Liu Shuzhen

2001, 22(1):  45-47.  doi:10.3969/j.issn.1000-1093.2001.01.012

Asbtract ( )   PDF (2956KB) ( )  

References | Related Articles | Metrics

The general structure, characteristic parameters and method of design of synchronous explosive circuit on a rigid surface are studied. Synchronization of multiple point detonation wave out?put is analyzed through error analysis. General expressions for the time of action and synchronization of multiple point detonation output are obtained. Technical measures for improved synchronization are also proposed.

Analysis of Atmospheric Ultraviolet Transmission by Computer Simulation

Jin Weiqi, He Yuqing, Wang Lingxue, Wang Zhongchun

2001, 22(1):  48-52.  doi:10.3969/j.issn.1000-1093.2001.01.013

Asbtract ( )   PDF (5952KB) ( )  

References | Related Articles | Metrics

Military needs for ultraviolet alarming and ultraviolet security communication appear as important demands for the development of ultraviolet sensing technology. In this paper，adopting the international atmospheric transmission simulation package LOWTRAN, atmospheric ultraviolet transmission under varying conditions of geographical locations，altitude，visibility，directions of light pathways and the transmission ranges are analyzed. Simulation results thus obtained can basically ex?plain some conclusions in current applications of UV sensing technology abroad, and are useful in guiding future research and development of UV sensing technology.

Relationship between Phase Difference and Range in FFT Phase-Comparing Ranging Radars

Xu Bangjian, Wang Zhan, Huang Fukan

2001, 22(1):  53-56.  doi:10.3969/j.issn.1000-1093.2001.01.014

Asbtract ( )   PDF (3826KB) ( )  

References | Related Articles | Metrics

CW phase-comparing radars are simple，accurate and easily adaptable to the adoption of digital signal processing technology. But precise relationships Detween the phase difference and range has not been seen reported on literatures. The paper studies such relations when FFT method is ap?plied to obtain the phase of signals.

Performance Analysis of Coded Noncoherent DS-SFH MFSK Modulation Spread Spectrum Communication Systems with Partial Band Multitone Jamming

Yang Wenge, Fei Yuanchun

2001, 22(1):  57-61.  doi:10.3969/j.issn.1000-1093.2001.01.015

Asbtract ( )   PDF (5327KB) ( )  

References | Related Articles | Metrics

The performance of MFSK modulation noncoherent hybrid DS-SFH spread spectrum communication systems with partial band multitone jamming is analyzed. On this basis the perfor?mance of MFSK modulation noncoherent hybrid DS-SFH spread spectrum communication systems that employ forward-error-control coding is analyzed and compared，the coding schemes analyzed in?clude ：Reed-Solomon codes (error-only decoding) and dual-k convolution codes. At the same time， the effects of partial band noise interference and forward-error-control coding on the hybrid spread spectrum system performance are discussed and analyzed.

Detection of Optical Pulses Based on Wavelet Transform

1：Song Zhengxun, Yin Fuchang；2：Dai Yisong

2001, 22(1):  62-65.  doi:10.3969/j.issn.1000-1093.2001.01.016

Asbtract ( )   PDF (4312KB) ( )  

References | Related Articles | Metrics

Signals in most laser systems are chiefly given in the form of pulses. This paper discuss?es the sorts and origins of noises in laser systems in complicated environments，taking as an example laser applications in the air channel. Based on its ability in detecting local characteristics of signals by the wavelet transform，the paper sets forth a technique of detecting optical pulses depending upon it. Emulation results and application conclusions are shown.

Estimation of Motion Parameters for Air Targets Based on Image Sequence Analysis

1:Shen Guowei, Lin Du;2:Guo Zhi

2001, 22(1):  66-69.  doi:10.3969/j.issn.1000-1093.2001.01.017

Asbtract ( )   PDF (3883KB) ( )  

References | Related Articles | Metrics

An approach of estimation of parameters for air targets based on image sequence analysis is proposed. The calculation formula for cases without disturbance is given，and ways of improving the calculation precision are discussed. Furthermore, the situation of the targets and imaging devices considering noise is studied. The recurrence formula of parameter estimation and the steady variance of estimation error are given.

Optical Fiber Spectrum Measurement of the Detonation Temperature

Yu Changqing, Yan Jun, Li Jiaze, Xu Gengguang

2001, 22(1):  70-73.  doi:10.3969/j.issn.1000-1093.2001.01.018

Asbtract ( )   PDF (4424KB) ( )  

References | Related Articles | Metrics

A method of determining the detonation temperature by measuring the spectrum is pre?sented. The measuring system consists of the optical fiber，the optical multichannel amplifier (OMA) and computer. The detonation temperature is derived by fitting the emission spectrum of the temporal detonation process with the Plank Dlackbody formula. Experimental results of detonation tempera?ture, emission spectrum and temporal response of explosive TNT are given.

Acquiring Attribute Weight of Multisensor Data Fusion by AHP

1:Lan Jinhui;2:Ma Baohua,Li Kejie;3:Li Youwen

2001, 22(1):  74-77.  doi:10.3969/j.issn.1000-1093.2001.01.019

Asbtract ( )   PDF (4029KB) ( )  

References | Related Articles | Metrics

The paper presents the idea of attribute weight of sensors to find out a method, in getting the confidence value of each sensor in multisensor data fusion for target classification. The Analytic Hierarchy Process (AnP) is applied to find out the attribute weight value of sensors. Structural mod?el of AHP for the attribute weight of sensors is proposed, showing that the method is effective through its applications.

Model Reference Variable Structure Control for the Control Channel of Laser Guided Bombs

Shen Yi, Liu Chong, Wang Huangang

2001, 22(1):  78-82.  doi:10.3969/j.issn.1000-1093.2001.01.020

Asbtract ( )   PDF (5013KB) ( )  

References | Related Articles | Metrics

In the control system of laser guided bombs，the control channel is a part of the guidance loop，and its parameters vary with the altitude and velocity of bomb — release. Based on these fea?tures ,a design scheme of model reference variaoie structure controller for a linear time-varying sys?tem is proposed. A controller for some type of laser guided bomb is designed, and simulation results showed satisfactory performance of the proposed method.

Numerical Simulation of Integrated Inner Flow in Solid Fuel Ramjet

Chen Jun ,Wu Xiaosong ,Qiu Guangshen

2001, 22(1):  83-85.  doi:10.3969/j.issn.1000-1093.2001.01.021

Asbtract ( )   PDF (2865KB) ( )  

References | Related Articles | Metrics

The integrated inner flow of SFRj including the mutation chamber，additional chamber and nozzle is numerically simulated by TVD scheme of N —S/Euler equations. Working processes of subsonic，transonic and supersonic field are studied, and second eddy in the combustion chamber is found. These can be used to reveal the complicated but stable working mechanism of SFRj .

Evaluating Missile System Performance Using the Fuzzy Analytical Hierarchy Process (AHP) Based on the Mean Value of Fuzzy Numbers

Zhang Zhiming, Wang Yue, Tao Ran ,Zhou Siyong, Shen Shenghong

2001, 22(1):  86-89.  doi:10.3969/j.issn.1000-1093.2001.01.022

Asbtract ( )   PDF (3505KB) ( )  

References | Related Articles | Metrics

Evaluation of missile systems performance reveals itself as a multiple attributes decision?making problem. The paper presents a fuzzy AHP method for the evaluation of missile systems based on fuzzy set theory and the Dempster-Shafer theory. The proposed method is more flexible and conve?nient due to the fact that it evaluates the criteria and missile systems，performance in fuzzy numbers using fuzzy AHP.Furthermore, because the proposed method orders fuzzy numbers through their mean values,it does not need to give arbitrarily an α-cut,its execution is much more intuitive and effective than with the traditional methods.

Determination of Bearings of Underwater Objects Based on Acoustic Intensity and Acoustic Pressure Gradient

1:Liu Xun, Xiang Jinglin, Luo Jian;2:Shen Yuanhai

2001, 22(1):  90-94.  doi:10.3969/j.issn.1000-1093.2001.01.023

Asbtract ( )   PDF (4670KB) ( )  

References | Related Articles | Metrics

A method based on acoustic intensity and acoustic pressure gradient is discussed and ap?plied to determine the bearings of underwater objects，especially of main engines and auxiliary engines radiating low frequency line spectrum noise. Principles and errors of the two methods in the presence of ocean ambient noise are analyzed.

Lie Symmetries and Conserved Quantities of Non-Holonomic. Systems of Non-Chetaev's Type with Unilateral Constraints Relative to a Non-Inertial Reference Frame

Li Yuancheng

2001, 22(1):  95-98.  doi:10.3969/j.issn.1000-1093.2001.01.024

Asbtract ( )   PDF (4230KB) ( )  

References | Related Articles | Metrics

This paper studies the Lie symmetries and conserved quantities of non-holonomic systems of non-Chetaev，s type with unilateral constraints relative to a non-inertial reference frame. The invari?ance of ordinary differential equations under infinitesimal transformations is used to establish the de?termining equations and restrictions of the Lie symmetries of the systems. The structural equation and conserved quantities are thus obtained. The inverse problem of Lie symmetries is then discussed. An example to illustrate the application of the results is finally given.

Segmentation and Classification of Adhesive Bond Images in Heat-Insulating Layers through Ultrasonic C-Scanning

yang Fengbao, Wang Zhaoba

2001, 22(1):  99-101.  doi:10.3969/j.issn.1000-1093.2001.01.025

Asbtract ( )   PDF (3553KB) ( )  

References | Related Articles | Metrics

Based on an analysis of ultrasonic C-scanning to detect the status of adhesive bond be-tween the heat-insulating layer and the case inside a rocket motor，the method of segmentation for ad?hesive bond images is proposed. Through this is realized the automatic classification of states of adhe?sive bond in heat-insulating layers. Experimental tests and applications show that the method is feasi?ble in practice.

Short Papers

Adaptive Control Method in Guii-Control Systems

Wang Xin, Li Ting, Pan Hongxia

2001, 22(1):  102-104.  doi:10.3969/j.issn.1000-1093.2001.01.026

Asbtract ( )   PDF (3417KB) ( )  

References | Related Articles | Metrics

A new methoa is put forward for the design of controllers in gun-control systems. Based, on the adaptive control principle，a new algorithm is proposed adopting the least variance control and the pole assignment method. It is simple and easily realizable in gun-control systems，and it is useful in improving the shoot precision of a marching gun. The results of computer simulation demonstrate that the method is efficient to the control system.

Modeling of Ground Motion Induced by Explosions

Lin Dachao, Bai Chunhua, Zhang Qi

2001, 22(1):  105-108.  doi:10.3969/j.issn.1000-1093.2001.01.027

Asbtract ( )   PDF (5143KB) ( )  

References | Related Articles | Metrics

The paper proposes a theoretical modeling method for the ground motion caused by ex?plosions. The relation between the parameter of ground motion and time is transformed into a pure random process with the amplitude varying with time. Based on the concept that there is the scaling invariant fractal structure in the transmission of earthquake motion and the self-affinity of the ground motion signal m time domain，an assumption is deduced that the curve of the stationary random noise of the ground motion varying with time is a fractal graph. Experimental results show that the power spectrum of the random oscillation function follows a power law，thus the Weiersterass-Mandelbrot (W-M) function is introduced, and the method and procedure of simulation for the ground motion pro?duced by explosions are presented. The theoretical predications are in good statistical agreement with experimental results for the displacements of vertical ground motion.

Adaptive Control Based on PID-Like Neural Network

Niu Yugang ,Yang Chengwu

2001, 22(1):  109-111.  doi:10.3969/j.issn.1000-1093.2001.01.028

Asbtract ( )   PDF (3113KB) ( )  

References | Related Articles | Metrics

The paper presents a new adaptive control system based on PID-Iike neural network, gives the learning algorithm of tnis new controller and analyses stability of the control system, simu?lation results are provided to demonstrate the effectiveness of the control schemes.

Experimental Techniques and Analysis

A study on Tungsten-Copper-Nickel Alloy as Shaped Charge Liner

Wang Fengying,Liu Tiansheng, Gou Ruijun, Wang YuLing

2001, 22(1):  112-114.  doi:10.3969/j.issn.1000-1093.2001.01.029

Asbtract ( )   PDF (3376KB) ( )  

References | Related Articles | Metrics

The paper studies the tungsten-copper-nickel alloy liner on its effectiveness in enhancing armor-piercing capability. The study makes a comparison with the copper liner and explores the dy-namic parameters of jets by X-ray. From the experiments is seen that enhancing the armor-piercing capability through the use of heavy metal tungsten-copper-nickel alloy as liner materials. Quiet ar?mor-piercing experiment of shaped charge without an insulating board indicates that the armor-pierc?ing capability is increased by 38 per cent in comparison with the copper liner，and the nigh expansibili?ty oi jet is showed by X-ray photographs.

Measurement of Dynamic Elastic-Plastic Fracture Toughness under Stress Wave Loading

Liu Ruitang, Jiang Fengchun ,Zhang Xiaoxin

2001, 22(1):  115-119.  doi:10.3969/j.issn.1000-1093.2001.01.030

Asbtract ( )   PDF (5186KB) ( )  

References | Related Articles | Metrics

An experimental method for measuring dynamic elastic-plastic fracture toughness is es-tablished. The Charpy impact specimen is loaded by an improved Hopkmson pressure bar. The inci?dent and reflected stress waves, which are recorded by strain gage glued onto the pressure bar，are used to calculate the loads and deflection of specimen according to the one-dimensional stress wave theory. The method can be applied in extremely low and high temperature conditions. The material’s dynamic stress-strain behaviors are taKen into account in calculating the dynamic elastic-plastic frac?ture toughness. So the JID value can well reflect the dynamic fracture properties of metals under stress wave loading.

Research Notes

Study and Application on Fuzzy Weighted Recurrence Least Square Algorithm for Real-Time Parameter Estimation Method of Time Series Model

Zhang Qi, Guo Jianyi

2001, 22(1):  120-123.  doi:10.3969/j.issn.1000-1093.2001.01.031

Asbtract ( )   PDF (3892KB) ( )  

References | Related Articles | Metrics

Parameter estimation is the key in building up a model in time series analysis. Datum sat?uration will emerge and the parameters estimated will depart from actual ones in conventional recur?rence least square algorithm when the data length increases beyond a threshold value. The paper pre?sents the basic theory and recurrence formulas for a fuzzy weighted recurrence least square algorithm in the time series model based on an analysis of the conventional recurrence least square algorithm. The results of application of the simulation and analysis are applied upon random road roughness for military engineering vemcles.

Dynamic Response Study and Experiments of a Trawler Carried Howitzer during Firing

1:Wang Jianping, Wang Jingquan;2:Chen Yunsheng ,Yang Guolai

2001, 22(1):  124-126.  doi:10.3969/j.issn.1000-1093.2001.01.032

Asbtract ( )   PDF (2895KB) ( )  

References | Related Articles | Metrics

The paper presents the dynamic model based on KanejS equation and having 10 degrees of freedom for a trawler carried howitzer during firing. Dynamic responses are obtained，from which the stability of iirmg and reliability of ship loading can be analyzed. Comparison of results between exper?iments and estimations showed fine consistency, and that the dynamic model and methods in calcula?tion are reliable.

An Amendatory Interior Ballistic Model Taking into Consideration Motions of the Gun

Yang Guolai ,Chen Yunsheng, Min Jianping

2001, 22(1):  127-129.  doi:10.3969/j.issn.1000-1093.2001.01.033

Asbtract ( )   PDF (3040KB) ( )  

References | Related Articles | Metrics

Kmetic relationships of projectile and gases are derived using analytical methods in dy?namics of multibody systems. Equations of interior ballistics are formulated, in which the motions of gun responses are considered, and the forces acting on the projectile are analyzed. The responses of gun-multibody systems are obtained by solving the differential equations of motion and equations of interior ballistics，which are of value to the structural design and the analysis for density of impact points.

Computer Aided ArmlyHis of the Radiation Characteristics of a Dielectric Rod Antenna

Huang Zhonghua, Cui Zhanzhong, Lin Sen

2001, 22(1):  130-132.  doi:10.3969/j.issn.1000-1093.2001.01.034

Asbtract ( )   PDF (2697KB) ( )  

References | Related Articles | Metrics

The expression of normalized pattern function of dielectric rod radiator is given. The ef?fect of antenna parameters on the beamwidth and side IoDe level is analyzed. With the aid of a comput-er, curves of beamwidth and side lobe versus the antenna parameters are plotted. This provides a the?oretical basis for the engineering design of fuze dielectric rod antennas.

Decomposition of NEAK Intermolecular Explosives

1:Zhao Shengxiang, Zhang Yian, Hu Huanxing;2:Lu Chunxu

2001, 22(1):  133-136.  doi:10.3969/j.issn.1000-1093.2001.01.035

Asbtract ( )   PDF (4173KB) ( )  

References | Related Articles | Metrics

The decomposition of NEAK (Nitroguamame-Ethylenediamine Dinitrate-Ammonium Ni?trate- Potassium Nitrate) eutectic intermolecular explosive was investigated by non-isothermal DSC and weight loss measurement under different temperatures.It indicated that the thermal stability of NEAK approaches that of EAK (Ethylenediamine Dinitrate-Ammonium Nitrate-Potassium Nitrate)， and when NEAK was mixed with NQ or RDX，the mixtures tend to have a higher decomposition speed.

A Neural Network Approach for the Acoustic Diagnosis of Adhesive Bond Quality between Metallic and Nonmetallic Components

Chen Shuyue ,Liu Guangpu, Yu Hongying,Huang Jinying

2001, 22(1):  137-140.  doi:10.3969/j.issn.1000-1093.2001.01.036

Asbtract ( )   PDF (4677KB) ( )  

References | Related Articles | Metrics

Basea on the ability of neural network in classification ana recognization，a feed-forward multi-layer neural network is applied in the diagnosis of adhesive bond quality between metallic and nonmetallic components of a pressure vessel through acoustic feature extraction in the frequency do-main, based upon the acoustic response on knocking the pressure vessel. It is shown that the method of extracting the feature and establishing the neural network model is effective for diagnosing the ad?hesive qualities.

Application of a Two-Step Least Square Method in the Measurement of Spinning Angle of Rolling Projectiles with Micro Gyros

Zhang Yiqun, Gao Zhongyu

2001, 22(1):  141-143.  doi:10.3969/j.issn.1000-1093.2001.01.037

Asbtract ( )   PDF (3310KB) ( )  

References | Related Articles | Metrics

Measurement of the spinning angle of a projectile is a key to the measurement of the projectile’s attitude. Because of the high spinning rate, a small fluctuation in the scale factor of the gyros will cause marked errors in the spinning angle，which invalids the measurement. To cope with the influence of the fluctuation，the scale factor to the state equation is adopted and a two-step least- square estimation method proposed by Gordon T. Haupt is used to estimate it. Simulation results show that the two-step method can estimate the spinning rate satisfactorily if the fluctuation of the scale factor is kept within 0.5%.