基于模糊交互多模型的机动目标跟踪方法

文中提出了一种模糊IMM（FIMM）算法,通过模糊逻辑推理得到IMM算法模型集中各滤波模型的匹配度,即模型的概率,代替IMM算法中通过交互组合计算模型概率的方法,该方法不需要IMM算法中的模型先验概率及马尔可夫转移概率,从而降低了算法的复杂程度。仿真结果表明,和标准IMM算法对机动目标的跟踪效果相比,文中提出的模糊IMM算法具有更高的跟踪精度,更快的收敛速度。     

基于改进自适应IMM算法的机动目标跟踪

文中提出了一种改进的跟踪机动目标的自适应IMM（AIMM）算法,采用协同转弯运动模型作为目标的机动模型,通过估计目标的角速度,并在估计参数值的周围选择数量一定的模型组成模型集来覆盖目标所有可能的运动模式,采用交互模型算法进行状态估计;应用变结构思想,将模型之间的切换理解为随机有向图,并综合利用前一时刻模型的后验概率和当前时刻模型的预测概率,计算模型之间的转移概率,从而能够根据目标（转弯）机动的情况,自适应地建立IMM算法的可变模型集。仿真结果表明,改进的AIMM算法的跟踪精度有了较大的改善,算法也更加平稳。     

基于HMM机动目标跟踪算法研究

在交互多模IMM的基础上,利用时变马尔可夫链切换系数对模型进行切换,实现对未知状态转移概率的自适应调节,提高了对机动目标的跟踪精度.仿真结果表明,改进后的IMM算法比IMM算法的跟踪精度更高,具有全面自适应跟踪能力.     

机动目标当前统计模型模糊自适应算法

针对当前统计模型常规算法跟踪机动目标的缺陷,提出了当前统计模型模糊自适应算法。该算法根据规范化的量测新息及其变化率并通过模糊推理实时选取机动频率,给出了加速度方差的新息幂函数调整方法,采用加速度估计值和预测值的偏差在线更新当前加速度均值。在此基础上,结合高斯隶属函数和强跟踪算法对其权值予以修正。当前统计模型模糊自适应算法不受机动频率人为给定和最大加速度极值设置的限制,适用于不同范围和程度的机动。利用当前统计模型模糊自适应算法对阶跃机动、圆周机动、Jerk机动3种典型机动场景进行了计算机仿真,并与当前统计模型常规跟踪算法和Jerk模型自适应算法进行了比较。仿真结果表明,该算法扩大了跟踪范围,具有较好的稳态特性和瞬态特性,其跟踪精度和收敛速度优于其他两种算法。     

基于期望系统噪声模型的自适应机动目标跟踪

对于机动目标跟踪问题,由于目标机动能力的增强,使建立的目标模型与目标的实际运动失配。为解决这个问题,需建立大量模型来逼近真实模式。但这使计算量增大,而且性能不一定能提高。本文提出基于期望系统噪声模型的自适应交互式多模型(IMM)算法。该算法自适应调整部分系统噪声模型,使之接近符合实际的系统噪声模型。对目标机动运动的Monte-Carlo仿真结果表明,本算法对机动目标的跟踪精度比标准IMM算法有较大改进,且计算量适中。     

基于"当前"统计模型的模糊自适应跟踪算法

基本的机动目标“当前”统计模型及其自适应卡尔曼滤波算法虽能对强机动目标进行很好的跟踪,但是在跟踪弱机动目标时却存在较大的误差。针对这一问题,新算法中引入一种非线性模糊隶属度函数来自适应地调整目标加速度上下限,并从理论上分析了新算法对于弱机动目标跟踪的有效性。通过计算机仿真验证了新算法相对于基本“当前”统计模型及其自适应跟踪算法的明显优势。     

自适应转弯模型的交互多模型算法研究

以强机动目标跟踪为背景,在分析常速转弯模型和IMM算法基础上,基于“当前”统计模型的设计思路．提出了自适应转弯模型。通过机动频率系数和角加速度方差修正常速转弯模型的系统状态噪声方差矩阵,设计了不同角速率的转弯模型集,给出了相应模型的状态转移概率,建立了一种自适应转弯模型的交互多模型算法。MonteCarlo仿真实验表明：该算法性能优于其它IMM算法,且计算量小。便于使用。     

一种用于仅有位置观测信息的机动目标跟踪滤波算法

在机动目标跟踪研究领域,"当前"统计模型自适应跟踪算法(ATS)在仅有位置观测信息的机动目标跟踪中具有一定应用价值。针对ATS算法中目标最大机动加速度为预设的常值,存在不能很好的适应各种机动情况的问题,对目标最大机动加速度进行实时自适应调整优化设计,使目标最大机动加速度以指数形式实时逼近加速度估值均值。改进后的滤波算法保持了原算法机动加速度的分布特性,提高了目标的跟踪精度。     

基于改进截断正态概率模型的机动目标跟踪算法

机动目标模型是水下目标跟踪的关键,在分析截断正态概率密度模型的基础上,利用前2个时刻的观测值与状态估计偏差,对该模型机动加速度与其方差的自适应关系重新进行修正,给出了一种基于改进截断正态概率密度模型的机动目标跟踪算法.该算法避免了加速度极限值的预先设定问题,从而提高了对机动目标状态估计的精度.仿真结果表明,该算法在跟踪水下机动目标时具有良好的跟踪性能.     

基于IMM-UKF的雷达/红外分布式加权融合算法

在雷达/红外复合制导机动目标跟踪背景下,针对非线性机动目标融合跟踪存在滤波器易发散问题,提出一种基于交互式多模型无迹卡尔曼滤波(IMM-UKF)的分布式加权融合算法。IMM具有对不同目标机动模式自适应跟踪的能力;UKF对观测数据进行滤波估计,避免了计算雅克比矩阵,克服EKF滤波方法受滤波初值影响大、易发散的缺点;分布式融合算法提高了系统抗干扰能力及对目标跟踪的有效性和跟踪精度。仿真结果表明:该算法在处理非线性系统机动目标跟踪融合结果误差均得到减少,更能提高目标跟踪滤波精度,增强了系统稳定性。     

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.     

Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection

For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.     

数码电子雷管中影响点火头性能因素分析

阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅（LTNR）的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明：一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。     

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.