一种空投水雷水下初始弹道的仿真

在对一种空投水雷水下无动力运动过程中运动受力分析的基础上,建立了研究其水下初始弹道的运动数学模型,并用Matlab软件编写实现了弹道仿真。仿真计算表明:研究的空投水雷在有水平均匀水流和入水角的情况下,一定深度范围内的初始弹道表现出逆流向运动特性,对减小散布距离有一定好处;在没有水平均匀水流情况下,入水角的增加比增大空投水雷入水速度对散布距离的影响更明显。     

基于MATLAB/Simulink的高速空投弹道仿真

采用MATLAB／Simulink对高速空投弹道进行仿真,建立外界因素影响的无伞空投弹道系统仿真模型。以空投鱼雷为例。分析空投高度、空投速度以及随机风对鱼雷空投弹道的影响,给出高速空投弹道的规律。该方法可以有效地应用到水中兵器空投弹道的仿真分析中,并为入水冲击水下弹道导引规律设计研究提供技术参考。     

空投水雷空中弹道设计与仿真

文中对空投水雷的空中弹道进行了研究.在建立了六自由度的水雷空中弹道模型的基础上,在Matlab/Simulink环境下对水雷的空中弹道进行了仿真,并分析了投雷速度、水雷初始俯仰角、空中自然风对水雷空中弹道的影响.     

入水参数对自导深弹攻潜弹道的影响与分析

为分析自导深弹的攻潜弹道,建立了自导深弹在纵平面内的弹道数学模型,利用MATLAB/Simulink软件对不同入水参数下深弹攻击作匀速直线运动的目标潜艇的弹道进行了仿真,仿真结果表明,攻击同一目标时,入水参数对自导深弹水下攻潜的弹道影响较大。该结果对空投自导深弹的战术使用有一定的参考价值。     

空投水雷安全性建模及仿真分析

为验证空投水雷空中投放的安全性,建立了其空投过程的运动方程和数学模型,并按照开伞之前、开伞以后和意外开伞3种情况进行了仿真分析。结果表明,该种水雷在3种情况下都能确保空投的安全性,后期进行的实投试验证明了模型和仿真分析的正确性。     

基于Matlab/Simulink的水下航行器建模与仿真

为便于对水下航行器的运动弹道和运动控制进行计算机仿真,建立一种基于Matlab/Simulink的水下航行器模型。利用矢量化建模方法,给出水下航行器6自由度空间运动数学模型,详细论述Simulink建模过程和S函数的实现方法,并应用所建立的Simulink模型,对水下航行器的开环运动、操纵性以及闭环运动控制相关问题进行仿真。仿真结果表明,该系统符合水下航行器的实际运动规律。     

高海况下伞弹弹道散布建模与仿真

在海上低空投放鱼雷、水雷以及深水炸弹等水中兵器时,入水参数即鱼水雷以及深水炸弹的水下弹道初始条件,将直接影响最终的攻击效果．其中落点散布和入水姿态是入水参数中关注的重点．本文建立了高海况下随机风及投弹条件误差影响的伞弹弹道模型．通过MATLAB平台利用蒙特卡洛模拟打靶法对弹道模型进行数值仿真．仿真结果可为理论射表的编拟和投弹试验提供理论依据．     

基于第二类拉格朗日方程的水雷内末弹道仿真

内末弹道是内弹道向中间弹道的过渡阶段,其运动参数关系到发射平台发射水雷的安全性。水雷经内弹道的高压气做功获得一定的出管速度后,在内末弹道阶段其仅在惯性的作用下继续运动,且其运动状态受到潜艇鱼雷发射管的约束。通过对水雷在内末弹道的运动受力分析,利用第二类拉格朗日方程建立内末弹道动力学模型,并在确定方程右端的广义力时加入了流体动力,给出了内末弹道参量与水雷出管速度的关系曲线图,仿真结果表明,适当增加水雷的出管速度可提高发射平台发射水雷的安全性。     

水雷攻击直升机弹道设计与仿真

针对传统水雷无法防范直升机的猎雷、扫雷问题,提出了利用水雷出水攻击直升机的解决方案,分析了出水过程中介质发生突变时水雷的受力变化,建立了水雷水中、空中运动方程组和直升机的运动数学模型,设计了水雷的出水攻击弹道,并通过仿真程序对攻击弹道进行研究。仿真结果表明,所设计的水雷攻击直升机弹道是可行的。     

无控上浮弹道散布因素仿真分析

传统无控火箭上浮水雷容易受到各种扰动影响,导致上浮弹道散布较大;基于水下六自由度刚体运动学模型,分析了初始条件与上浮过程扰动等主要影响因素,建立了含扰动的上浮弹道数学模型,并通过数值仿真计算,分析了上述因素对上浮弹道出水点偏移的影响程度,为工程实际解决上浮弹道散布问题提供参考.     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.