反潜巡逻机应召布放多基地声纳阵搜潜效能研究

为提高反潜巡逻机传统应召搜潜效能,提出采用反潜巡逻机应召布放多基地声纳阵的方法.在传统方法的基础上,根据已知的潜艇信息,利用多基地声纳的优势建立反潜巡逻机应召布放圆形、方形、三角形多基地声纳浮标阵搜潜模型,依据声波衰减原理,通过Matlab仿真初始距离,潜艇初始概略分布、潜艇经济航速、布放半径和被动浮标布放个数对各方案搜潜效能的影响.仿真结果表明:3种多基地阵方案的搜潜效能随着初始距离、初始概略位置分布、潜艇经济航速的增大而减小.在相同条件下,圆形多基地阵的搜潜效能最佳,且相比同样基于传统方法的圆形被动浮标阵搜潜效能提高明显,并能根据实际情况选择合适的布放半径和被动浮标布放个数.该方法适用于反潜巡逻机应召搜潜,对反潜作战具有一定的军事意义.     

基于先验目标分布的磁探仪应召搜潜最佳圆周搜索半径研究

为提高反潜巡逻机利用磁探仪执行应召螺旋搜潜的搜潜效能,运用概率论和最优搜索理论对最佳圆周搜索半径进行研究.综合考虑目标初始位置、航速和航向等分布的特点,建立了磁探仪圆周搜潜概率的解析模型,据此推导出最佳圆周搜索半径.根据飞行线路模拟算法,结合反潜巡逻机的机动性能,建立了反潜巡逻机利用磁探仪执行螺旋搜潜时的航路规划的数学...     

反潜巡逻机磁探仪检查搜潜效能研究

针对潜艇自身的磁异常会引起地磁场扰动的特点,可以利用磁探仪探测安静型潜艇。根据检查搜潜的特点,结合反潜巡逻机使用磁探仪对潜搜索的方法,分别建立单机和双机使用磁探仪检查搜潜的数学模型,并通过仿真计算,分析搜索区域面积、磁探仪探测作用距离的变化对搜索发现概率的影响。仿真结果证明,该方法能为磁探仪的优化使用提出有效建议。     

Research on Efficiency of Checking Search Submarine by Magnetic Anomaly Detector on Antisubmarine Patrol Aircraft

针对潜艇自身的磁异常会引起地磁场扰动的特点,可以利用磁探仪探测安静型潜艇.根据检查搜潜的特点,结合反潜巡逻机使用磁探仪对潜搜索的方法,分别建立单机和双机使用磁探仪检查搜潜的数学模型,并通过仿真计算,分析搜索区域面积、磁探仪探测作用距离的变化对搜索发现概率的影响.仿真结果证明,该方法能为磁探仪的优化使用提出有效建议.     

航空磁探仪探潜目标磁梯度定位方法

以反潜巡逻机使用光泵式磁探仪为例,提出一种利用航空磁探仪对潜艇进行磁梯度定位的方法。在较详细地分析潜艇的磁场特性,建立磁场模型的基础上,对反潜巡逻机装备磁探仪如何利用磁梯度矢量来探测潜艇和对潜艇进行定位进行分析,建立了相应的模型,并根据航空磁探仪探潜的特点,将航空反潜中潜艇的远场磁信号等效为磁偶极子磁场。结果表明,通过对潜艇位置做的3次跟踪探测,能较准确地定位潜艇的位置。     

应召搜索中潜艇位置散布分析

针对当前搜潜效能评估时,潜艇位置模型假设存在不合理和过于简单的情况:提出了在应召搜索时合理分析潜艇位置散布规律的必然性,以及应召搜索时潜艇分布的特点;分析了应召搜索中潜艇初始位置和潜艇运动后的位置散布规律,并分别推导出潜艇的概率密度函数;由计算结果表明模型的准确性,为计算搜潜效能提供一定的理论依据。     

基于多基地声纳的反潜巡逻机检查搜潜效能研究

为解决传统反潜巡逻机检查搜潜存在作用距离短、搜索盲区大、精度低和经济性差的缺点,提出基于多基地声纳的反潜巡逻机检查搜潜方法.根据反潜巡逻机先布设的多基地声纳阵得到潜艇初步定位坐标,以4种不同的方案补投被动浮标,并利用声波衰减原理和TOL算法分别通过Matlab进行多基地搜索概率和GDOP定位精度的仿真.仿真结果表明:同等条件下,反潜巡逻机进行等边三角形补投被动浮标情况下的多基地声纳检查搜潜方法具有高搜索概率和定位精度,并能使用较少的浮标形成一个有效的检查圈.该方法可应用于反潜巡逻机检查搜潜,对反潜作战具有一定的军事意义.     

使用航空自导深弹多次攻潜方法

针对反潜巡逻机使用航空自导深弹的攻潜作战问题,给出了多次深弹攻击的定义,分析了多次深弹攻击的使用时机和攻击参数。在建立连投航空自导深弹攻潜效能评估模型的基础上,通过仿真计算,研究了潜艇目标采取纯机动对抗和使用声诱饵对抗时,多次连投深弹攻击的合理攻击参数和命中概率,总结了反潜巡逻机多次连投深弹攻潜作战的方法。     

吊放声纳螺旋形应召搜潜效能仿真研究

吊放声纳是目前反潜直升机有效搜潜的主要设备之一。建立了蒙特卡洛法模型对双机螺旋线形应召搜潜概率进行了仿真,重点仿真计算了反潜直升机在一定条件下搜潜时潜艇最大航速、吊放声纳间隔系数、搜索航线螺旋系数和起始搜索点对搜潜概率的影响,并给出了仿真结果分析,得出的相关结论可为反潜直升机作战战术决策提供理论依据。     

反潜巡逻机使用浮标声纳和自导深弹攻潜模型仿真

针对反潜巡逻机使用声纳浮标和自导深弹的攻潜效能研究,提出了一种基于蒙特卡洛法的效能评估模型。在建立了攻潜坐标系的基础上,定义了连投深弹射击深度的概念;给出了浮标声纳系统定位目标条件下,反潜巡逻机连投深弹的散布模型和目标分布模型;依据攻潜过程和命中判定条件,进行攻潜效能的仿真计算;最后,通过仿真结果证实了方法的有效性,并提出了一种连投深弹时投弹间隔的确定方法。     

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.     

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.     

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.     

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.     

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.     

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.