Table of Content

31 March 2003, Volume 24 Issue 1

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Paper

Simulation and Analysis of the Dynamic Behavior for a Flexible Spin Rocket Launching System as Effects of Clearance

Zhu Huailiang

2003, 24(1):  1-4.  doi:10.3969/j.issn.1000-1093.2003.01.001

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This paper investigates the dynamic behavior on a flexible spin rocket launching system having a clearance. The attitude, binding forces and frictions of the spinning rocket are described, based upon the varying contact stiffness and relative deformation traversed between the rocket and the launcher. Dynamic responses are obtained via the numerical method, and influence of the clearance between the rocket and launcher on rocket’s motion attitude and binding forces are analyzed.

Optimal Design of the Structural Parameters of a Self-Propelled Gun

Mao Baoquan, Mu Ge

2003, 24(1):  5-9.  doi:10.3969/j.issn.1000-1093.2003.01.002

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To improve the shooting accuracy of a self-propelled gun, the optimum design of the structural parameters of a self-propelled gun takes the initial disturbance of the gun muzzle as an objective function. Moaels of shooting dynamics and parameter optimization are set up. The Droblems are resolved through tne projected gradient state space method and satisfactory results are attained.

Development of a CAD System for the Cylinder Head of High-Speed Heavy-Duty Vehicular Diesel Engines

Zou Yuan, Liao Ridong, Zuo Zhengxing, Wang Wenqing

2003, 24(1):  10-14.  doi:10.3969/j.issn.1000-1093.2003.01.003

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cylinder head is one of the largest and the most complex parts in an engine[1] . Application of CAD is greatly limited due to the complexity of its structure. Today,the development of CAD for the cylin?der head system is a field yet to be unfolded in China. Based on the I-DEAS Master 6.0，utilizing fully func?tions of the Open ideas and applying techniques of parametric modeling based on features,object orientation and database techniques,a CAD system for the cylinder head of high-speed heavy-duty vehicular diesel en?gine is developed. It is an integrated system involving 3D-modeling, 2D-graphics, FEM analysis and Opti?mization. In this way a software environment for the design of cylinder head is established.

A Numerical Study on the 3-D Airflow & Heat Transfer in an Armored Personnel Carrier Passenger Compartment

Liu Xixia, Bi Xiaoping ,Zhao Yixian

2003, 24(1):  15-18.  doi:10.3969/j.issn.1000-1093.2003.01.004

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A physical and mathematical model for the computation of 3-D airflow and heat transfer in an armored personnel carrier passenger compartment is set up. By a two-equation k-e turbulence model and FVM(finite volume method)with unstructured grid, the 3-D distributions of airflow and temperature fields in an armorea personnel carrier passenger compartment are numerically calculated. A theoretical basis for the study on the optimization of the armored personnel carrier passengers，survival environment was given.

A Study on the Optimal Matching of Dynamic Parameters for a Floating Automatic Mechanism

Yao YangWu, Wang Gang

2003, 24(1):  19-22.  doi:10.3969/j.issn.1000-1093.2003.01.005

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On the basis of an analysis of the matching principle of motion for the floating automatic mechanism, the dynamic optimal model and two-freedom simulation model of the floating automatic mecha?nism are established. Optimal matching and numerical simulation are carried out for an automatic grenade launcher. The results show that the dynamic parameter matching of the floating automatic mechanism is reasonable and the mechanism will attain steady floating firing.

Model for Finding Firing Data of Shipbome Gun Weapon System by Solving External Ballistic Equations

1：Hu Jiasheng；2：Yang Shaoqing,Wang Dehu；3:Pan Honghua

2003, 24(1):  23-26.  doi:10.3969/j.issn.1000-1093.2003.01.006

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The paper presents a model that can be used to obtain accurate firing data of shipbome gun weapon system by solving external ballistic equations. The model presented in the paper includes the method to calculate the firing data and flight time with the target position by solving the external ballistic e- quations once only, as well as methods to correct the informal ballistic and meteorological conditions, move?ment of the ship and the side deviation of projectiles. The method presented in the paper can be used to re?duce the calculation of finding firing data of the shipbome gun weapon system by solving the external ballis?tic equations, thus raising the calculation speed.

On the Uniformity Test of Ballistic Curves

Ni Zhongren, Tian Fang

2003, 24(1):  27-29.  doi:10.3969/j.issn.1000-1093.2003.01.007

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It often happens in the uniformity test of ballistic curves that despite the disperse hypothesis tests are found to stand as true, but the total test fails to be ratified. The paper studies the relationship be?tween disperse tests and total test in the uniformity test of ballistic curves. It has been given the relationship of the critical values are obtained through the principle of conditional extreme value. With this an effective method is arrived at to decide the total test from information of disperse tests.

A Study on the Method of Judgement for Target Hitting in shooting Emulation

1:Qi Zhanyuan;2:Xu Wenxu, Zhang Gengyu

2003, 24(1):  30-33.  doi:10.3969/j.issn.1000-1093.2003.01.008

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This paper studies the method ot judgement for target hitting in digital shooting emulation. By studying the necessary conditions of hitting the target, the judgement process is limited in a smaller area near the target; One can then establish a target equivalent that may predigest the target shape. Using kine?matics theory, the movement of the bullet and target in ground coordinates can be transformed to the rela?tive movement of the pullet in the target coordinates. Then the corresponding movement equation can be es?tablished and point of intersection of the calculated bullet movement track and the target equivalent surface will furnish information of hitting the target. Calculations can be greatly reduced. The judgement process becomes independent and adaptable for computer. The method provides landing velocity and landing angle besides the coordinates of hitting the target，and offers conditions for validity judgement of hitting the tar?get.

Effects of Randcan Factors on the Processes of Laser Ignition of Propellants

Zhang Xiaobing, Yuan Yaxiong, Ren Ruhai ,Yang Junyun

2003, 24(1):  34-37.  doi:10.3969/j.issn.1000-1093.2003.01.009

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Laser ignition can improve the ignition performance of packed propellant beds and avoid local ignition. Nevertheless, in the process of laser ignition, such parameters as particle diameter, laser energy, laser diameter, pulse width are all random. In this paper, the effects of these random factors on the ignition delay oi single particle and on the ignition delay of multipoint uniform ignition are investigated.

On the Policy and Realization of SNMPvl-Based Hierarchical Network Management

1:Pan Chengsheng,Liu Yong;2：Jiang Yueqiu,Wang Guangxing

2003, 24(1):  38-41.  doi:10.3969/j.issn.1000-1093.2003.01.010

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SNMPvl is often selected today as a kind of network management protocol to many of its clients. Yet SNMPvl has no identified communication between managers, so it can not manage a large net?work. For a complex tree type of organization based on SNMPvl, there is no network management plat?form and applications that allows the upper network to manage its subordinate networks. A method is pro?vided in this paper to implement a WAN Hierarchical Management by properly creating data structure and synchronizing between them. It has been implemented on an analogous system of a high ranking communi?cation network.

Design of Wide Angle space Optical Systems of Long Focal Length

1：Chang Jun, Jiang Huilin,Jin Yingji；2：Weng Zhicheng ,Cong Xiaojie

2003, 24(1):  42-44.  doi:10.3969/j.issn.1000-1093.2003.01.011

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Design of optical systems of long focal length, wide field and minimized size has long been the focus of discussion. When the aperture diameter of an optical system is fixed with the same orbit height, the resolution of ground objects can be improved by increasing the focal length. Meanwhile, by increasing the field of view the width of the ground covered can be widened. The system designed has a focal length of 10m and a field of view of 6° . All the 3 reflecting system surfaces are aspheric thus avoiding the effect of central obstruction. Evaluations have shown that the image quality is close to the diffraction limit.

Passive Target Motion Analysis and Its Performance Based on Two Arrays

1:Hu Youfeng;2:Li Yingchun

2003, 24(1):  45-50.  doi:10.3969/j.issn.1000-1093.2003.01.012

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Problems in passive target motion anslysis based upon two arrays are discussed. In the condi?tion of two arrays, bearings and frequency of the target obtained by each sensor on two arrays are used as inputs. Target motion parameter estimation is directly presented in the fusion center, an example Demg giv?en in PLE and EKF, for which the Cramer-Rao lower bound is discussed. The results of simulation experi?ments show that approaches proposed here can improve the performance of motion parameter estimation and reduce its localization error ellipse significantly. It can be prompted to multiple arrays.

A Study on the Building Up of Models and the Ambiguity Function of “Sync-Plus -White” Signal of Television-Based Bistatic Radar at Low Altitudes

1：Guo Qiang, Tao Ran, Wang Yue;2:Sha Nansheng, Zhu Xinzhang

2003, 24(1):  51-56.  doi:10.3969/j.issn.1000-1093.2003.01.013

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From the angle of target-detection, the target echo model for a low altitude target rectilineally approaching the receiver of a bistatic radar is built up and its accuracy analyzed. On the basis of the model and the ambiguity function of rectangular pulse, the mathematical expression for the ambiguity function of sync-plus-white” signal is derived using overlapping method, and the ambiguity plot and intersection of the signals in one and several periods at the time and frequency axis plotted. This makes the detectability of sync-pius-white” signal well known and lays a foundation for further study on target detection using this Kind of signals in the future.

Improved Resolution of Radar Aamuth by ISAR

1:Wang Shengli;2:Ni Jinlin, Zhang Guangyi

2003, 24(1):  57-61.  doi:10.3969/j.issn.1000-1093.2003.01.014

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This paper deals with an approach for improving the resolution of radar by increasing the e- quivalent radar antenna aperture through motion of targets and decreasing its equivalent beamwidth. Theo?retical analysis and computer simulation were carried out for which the increment in equivalent radar anten?na aperture and the number of detection upon the resolution of radar azimuth are discussed. It is seen that higher resolution can be attained under certain conditions.

Transparent Infrared Coatings and Far Infrared Low-Pass Filter

Che Ying, Dong Lianhe, Wang Ye

2003, 24(1):  62-64.  doi:10.3969/j.issn.1000-1093.2003.01.015

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Composite action of transparent infrared coatings and electromagnetic attenuation are studied. Transparent infrared coatings with the function of electromagnetic attenuation were made, the linewidth and pitch of the electromagnetic attenuation grids were designed and calculated, the experimental results are given and analysed, and proposals for further improvement are given.

A Study on the Reconstruction Bias Originating from Error of Focal Distance of X-Ray Source

Lu Hongnian, Yang Min, Zhang Li

2003, 24(1):  65-67.  doi:10.3969/j.issn.1000-1093.2003.01.016

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The degradation in quality of reconstructed image caused by the error in the focal distance of X-ray source is discussed. Computer simulation and experimental results proved that this kind of influence is not obvious when the focal distance is much longer than the size of the reconstructed object. In addition, the influence close to the center is less than that close to the edge of the reconstructed object.

Reconfigurable Control System Design for Autonomous Underwater Venicle by Dynamic Output Feedback

1:Ren Zhang;2:Yan Weisheng, Tang Xiaojing

2003, 24(1):  68-73.  doi:10.3969/j.issn.1000-1093.2003.01.017

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To design a reconfigurable control system for a class of autonomous underwater vehicle, a method for reconfigurable control system design is proposed under the condition mf- rf — 1 < n (where n， mf，rf represent the order of states, inputs and outputs of a fault system, respectively) . A compensator with order l is injected into the feedback loop, and then the plant and the compensator is integrated into an extended system with order n + l. All n + l eigenvalues of the extended system may be freely assigned to the desired place by suitably choosing l，the order of the compensator, which makes the performance of re?configured control system recover that of normal system. One of advantages of the method is that if the fault system were controllable and observable after any fault in plant，there always exists a compensator with suitable order which makes n +l eigenvalues of the extended system freely asignable, and then the performance of reconfigured control system may recover that of a normal system. The stability of reconfig?ured control system can be guaranteed. The reconfigurable control system for AUV coupled by yaw and roll system of AUVand simulation results demonstrate the effectiveness of the method proposed.

Vortex Suppression and Resistance Reduction by Magnetohydrodynamic Force

Fan Baochun, Jiang Xiaohai, Ye Jingfang

2003, 24(1):  74-77.  doi:10.3969/j.issn.1000-1093.2003.01.018

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A blunt body moving in a fluid is acted upon by drag forces and Karman vortex will appear be?hind it when the Re number is large enough. Numerical simulations are performed for the cylinder wake with open or closed loop control in electromagnetic fields. The possibilities of vortex suppression and resis?tance reduction by magnetohydrodynamic forces in a low conducting electrolyte solution are discussed based on calculated results.

A New Model of Threat Evaluation Involving Qualitative and Quantitative Objects

1:Huang Xiancheng;2:Chen Shouyu

2003, 24(1):  78-81.  doi:10.3969/j.issn.1000-1093.2003.01.019

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Based on the analysis of actual military requirements, threat in military actions was regarded as a fuzzy concept. Threat evaluation was considered as a non-structural multiple objective assistant decision making problem that comprises quantitative and qualitative objects. According to the engineering fuzzy set theory, a model involving qualitative and quantitative objects was presented for evaluating the threat of hos?tile targets. Then, a new algorithm that uses fuzzy values of relative important degrees of adjacent objects was proposed for converting the mood operators into fuzzy values and resolving the objective weight and rel?ative threatening degree of qualitative objects. The model and the algorithm are simple, real-time, all-pur?pose, and makes it easier to utilize the experience of military experts in military decision making systems. The example shows that the model can reflect the true threat of targets more objectively and accurately, and will advance the intellectualized-level of C3I.

Non-Central t-Distribution Used in the Lower Limit Calculation of Reliability

Jin Xing, Hong Yanji, Wen Ming ,et al.

2003, 24(1):  82-84.  doi:10.3969/j.issn.1000-1093.2003.01.020

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Calculation of non-central ,-distribution and its quantile is required in reliability analysis, for example, analysis of lower tolerance limit for normal distribution, upper confidence limits of coefficient of variation for normal distribution, lower limits of reliability for normal distribution. Based on Gauss integral method and non-central -distribution, a new method for the calculation of non-central t一distribution and its quantile is presented. Timesaving and high precision is its characteristic. The method is easily used in the reliability analysis for normal distribution.

Nolinear Coupling Dynamic Simulation of a Drill and of a Drillstring System

1:Zhu Caichao, Xie Yongchun;2:Liu Qingyou

2003, 24(1):  85-88.  doi:10.3969/j.issn.1000-1093.2003.01.021

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Based on an analysis of the vibrational states of the drill string，an integrated dynamic model of the drill string system is set up, that includes the endwise, sidewise, and torsional vibrational states. The principle of drill string vibration is analyzed. At the same time, combining the mutual dynamic rela- tions on aiguille-rock and a numerical calculation the integrated dynamic model of the drill string system is developed. Dynamic simulation experiments have been completed.

On the Almost Sure Sample Stability of Stochastic Nonholonomic Systems

Shang Mei, Mei Fengxiang

2003, 24(1):  89-92.  doi:10.3969/j.issn.1000-1093.2003.01.022

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This paper studies the almost sure sample stability of stochastic nonholonomic systems chiefly by way of the linearization. Taylor expansion is first taken for the coefficient oi the nonlinear stochastic nonoholonomic system omitting the higher terms, i.e.，keeping only the linear terms, such tliat linearized stochastic nonholonomic systems are obtained. The stability problem of the perfect systems can then be studied via the linearized stochastic nonholonomic systems and regions of asymptotic stability of nonlinear stochastic nonholonomic systems are determined according to its the linearized stochastic nonholonomic sys?tems.

A Study on the Motion Reliability of Mechanisms

Li Yenong, Shi Zukang

2003, 24(1):  93-96.  doi:10.3969/j.issn.1000-1093.2003.01.023

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Motion reliability design of mechanisms is divided into two branches, viz. the movement relia?bility design, and the reliability design of displacement accuracy. In this paper, design principles concerning the reliability of displacement accuracy are expounaed m more detail. Length of component and clearance in mechanisms are taken as vectors，and the primary error and wear of kinematic pairs in mechanisms are tak?en as variables. A formula of error of the resultant movement is deduced, and a formula on the reliability of displacement accuracy is thereby deduced. With the increase in wear the reliability ot displacement accuracy decreases. Relationship between reliability and wear is thus found. Using this method, the service life of mechanisms can be computed.

A Study on Some Key Techniques in the Structural Dynamics Optimal Design of a NC Internal Grinder

Hu Rufu, Sun Qinghong, Chen Nan, Chen Xin, Mao Haijun

2003, 24(1):  97-101.  doi:10.3969/j.issn.1000-1093.2003.01.024

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Structural dynamics optimal design is an effective approach to improve the machining accuracy of machine tools. Some key techniques in the structural dynamics optimal design of NC internal grinder are analyzed, including structural dynamics optimal design of components applying sensitivity analysis, the set?ting up and correction of finite element (FE) model of combined surfaces between components, optimization of the spindle system applying BP neural networks model, the application of multi-tuned mass damper (MT- MD) with distributed frequencies to restrain vibration. The NC internal grinder MK2120A so designed has higher accuracy. Ihe grinding accuracy reaches the following results： roundness 0.0008 — 0.0011mm, cylindrical error 0.0015mm, surface roughness Ra 0.1μm, grinding vibration stripes are eliminated, and the weight of the whole grinder is greatly reduced. These will also be of benefit in guiding the structural dynamics optimal design of other machine tools.

Heading Teaching-Playback Based Path Following Control for a Tracked Mobile Robot

Cong Jianwei, Gao Junyao,Xiong Guangming

2003, 24(1):  102-105.  doi:10.3969/j.issn.1000-1093.2003.01.025

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A heading teachmg-playback based path following control method with the least devices for tracked mobile robot is presented. In the teaching process, the heading oi tne robot is recorded and held in the teacning file for each fixed distance. They are then used as the desired heading in the heading playback controller. The navigational principle of the method is dead-reckoning. Experimental results show that, combined with limited telecontrol interference, it can fulfill the path-following task simply and effectively. Moreover, according to the experimental results，the cause of the following error is analyzed and some ways to overcome them are given.

Comprehensive Reviews

Progress on the Semiconductor Bridge initiator

Zhu Fengchun, Xu Zhenxiang ,Chen xiwu, Zhou Bin, Qin Zhichun, Tian Guirong, Hou Sujuan

2003, 24(1):  106-110.  doi:10.3969/j.issn.1000-1093.2003.01.026

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Semiconductor bridge (SLB) initiator represents a novel one kind of initiating device. It has been developed very rapidly due to its excellent properties, such as its high safety, high reliability, high synchronization, a high coherence of technologies, low fire energy and its readiness of incorporation with the digital logic circuits. In this paper are reviewed the theory, configuration, packing, test and improve?ment of SCB initiators and its future prospects. In addition, it is pointed out that semiconductor bridge (SCB) initiator is the ideal substitute for the bridge initiating device and has more extensive area of applica?tion. The Key point in its future development lies in the basic theory，the automatization of production, ig?nition by low voltage and passivated technology of in-line explosives.

A Review of Relevant Studies on Wet Multiple Brakes

1:Zhao Wenqing;2:Wang Chunsheng

2003, 24(1):  111-114.  doi:10.3969/j.issn.1000-1093.2003.01.027

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In the paper, are summarized results of study both home and abroad on wet multiple brakes concerning mechanism of convection and heat exchange, rule of distribution of compressive stress, as well as of temperature and heat stress field, mechanism of friction and braking the noise. Besides, reviews rele?vant to heat dissipation characteristics, experimental and theoretical research aspects such as multiple object optimization design and three dimensional CAD modeling on wet multiple brakes are given as well. In the case of some issues new ideas and opinions about wet multiple brakes are put forward, and new trends and development in the future are further probed into.

Experimental Techniques and Analysis

Quantitative Determination ol Polynitropolyphenylene in an Insensitive ana Highly Energetic Booster Explosive

Bai Hongjuan, Zhang Jinglin

2003, 24(1):  115-117.  doi:10.3969/j.issn.1000-1093.2003.01.028

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The content of polynitropolyphenylene in an insensitive and highly energetic booster explosive is determined using a 751G ultraviolet spectrophotometer. Determination of the point of intersection of ab?sorption curves and the equal absorption point are unnecessary in this method, while the regression curves are of better stabilities. The results of analysis for polynitropolyphenylene content show that the average re?covery ratio is 100.5%(n =8,relative standard deviation RSD = 2.5%), and the standard deviation is less than 0.0596(72 = 8). The accuracy of the method is analyzed by means of regression theory.

Laser Scanning Measurement for High Temperature Deformation of Materials

1:Zhang Guoyu, Xu Xiping, Yang Lin ,Li Chengzhi;2:He Fengmei, He XiacWa

2003, 24(1):  118-120.  doi:10.3969/j.issn.1000-1093.2003.01.029

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A laser scanning measuring method and system is presented. It is used in the non-contact measurement of the high temperature deformation of materials and their linear coefficient of expansion, based on the laser slit scanning measurement and the infrared temperature measurement technology. In this paper, the measuring system and measuring principle are discussed in detail. Using this measuring system, high temperature deformation or linear expansion coefncient of materials is measured. Experimental results manifest that the system works satisfactorily with samples at 1000°C and 3000°C and at standard distances from 30 ?50mm. Its measuring precision can reach 士 3μm. The system can provide nigh temperature characteristics of new types or composite materials.

Free-Surface Velocity of Metal Parts Driven by Explosives Measured with VISAR Interferometer

1：Chen Lang；2：Feng Changgen

2003, 24(1):  121-124.  doi:10.3969/j.issn.1000-1093.2003.01.030

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For observing the details of movement of metallic parts driven by explosive detonation, free- siirface velocities of the metal plates were measured with the VISAR interferometer. Processes of obtaining parameters for the VISAR interferometer and ways of dealing with the originality wave signals are intro?duced. Loss oi signals and the methods for judging the numbers of lost stripes, and the revision of velocities are discussed. For the single sensitiveness VISAR interferometer, the numbers of lost stripes in signals can be judged by calculating the velocities so as to get accurate experimental results.

Experimental Investigation of the Effect of Gumey Flap on Airfoil Aerodynamical Characteristics

Zhou Ruixing, Gao Yongwei ,Shangguan, Yunxin, Xiao Chunsheng， Xi Zhongxiang

2003, 24(1):  125-127.  doi:10.3969/j.issn.1000-1093.2003.01.031

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Increase in the lift of an aircraft will widen its applicability. In this paper, the effects of in?creasing the lift and flow characteristics around a single airfoil with the Gumey flap are studied by experi?mental methods of surface pressure, boundary-layer and wake measurments. The experimental results indi?cate that the effect of Gumey flap in increasing the lift is closely related with the height of the flap. Gumey flap can increase the lift coefficient of an airfoil to 53 % , when a = 8° and height = 3 % c ?

Research Notes

Case Based Reasoning (CBR) Framework for the Scheme Design of Small Arms

Fang Jun, Liu Changyi, Xu Cheng

2003, 24(1):  128-132.  doi:10.3969/j.issn.1000-1093.2003.01.032

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Presents an object-oriented framework for case-based reasoning (CBR Framework)，describes its architecture and implementation, and its applications in developing the scheme design system of small arms. At the same time,, an object-oriented reasoning model with XML-based case representation is set up. On the basis of this work, a prototype system for the automatic mechanism scheme design is developed and an example is given to depict the system.

Development of a Miniature Short-Range Synthetic Aperture Radar System (Sar) and Radar Imaging

1:Li Daojing ,Yu Sianzhang;2:Zhang Chunrong, Li Jianling

2003, 24(1):  133-135.  doi:10.3969/j.issn.1000-1093.2003.01.033

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A miniature short-range SAR prototype system has been developed and its main technical pa?rameters are here introduced. Its design concept and engineering implementation are described briefly. For the miniaturization of radar system, solid-state transmitter and micro-strip antenna are used in the radar transmit-receive unit, and the SAW device is used to implement the generation of large time-bandwidth product LFM signal and pulse compression with 3m resolution of slant range. System tests on SAR mode by means of a small airplane and on ISAR mode by means of a tracking radar as well as the imaging algorithm are presented. Imaging results based on real data have ventied the system’s excellent performance and suc- cessful resolution.

Estimation of Signal-Noise Ratio Based on Correlation Coefficients

Zhang Pizhuang, Han Yan

2003, 24(1):  136-138.  doi:10.3969/j.issn.1000-1093.2003.01.034

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A new method was introduced whereby the signal-noise ratio of a digital signal can be estimat?ed directly with the correlation coefficient between two series of digital signals. Based on the two series of digital signals under the same conaitions, the relationship between the correlation coefficient and signal- noise ratio was induced and ways of noise-analysis in the case oi images were shown. Two examples through different approaches were contrasted and analyzed.

Experimental and Analytic Study on Factors Influencing the Sedimentation Properties of Long Working-Time Sustained Solid Rocket Motors

Chen Jun, Wang Zhengshi, Dang Shiyan

2003, 24(1):  139-141.  doi:10.3969/j.issn.1000-1093.2003.01.035

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On the basis of many high, low and ordinary temperature static experiments on long working?time sustained solid rocket motors using high energy composite propellants, a study of factors influencing the sedimentation properties was performed and analyzed, for instance dimension of nozzle throat, material of throat, construction of nozzle, character of propellant, etc.，besides effects on internal ballistic stability and reproducibility of SRM. Sedimentation properties and their rules are derived. They can be useful refer?ence for the design of similar motors.

A Study on the Ultrasonic Honing of Motor Cylinders

1:Zhu Xijing, Wang Ailing, Xin Zhijie;2:Yuan Yi;3:Xu Mongjun

2003, 24(1):  142-144.  doi:10.3969/j.issn.1000-1093.2003.01.036

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A new processing technology—ultrasonic honing is introduced, giving the principle,specifici?ty ,equipment structure, effect of processing and applicational prospects when used in motor cylinders for tanks.