雷达目标识别发展回顾与实现中的关键理论

雷达目标识别作为智能化武器发展的关键技术,在未来信息化条件下联合作战中发挥着极为重要的作用.阐明了雷达目标识别研究的科学意义,回顾了该领域的发展过程及已取得的研究成果,分析了基于高分辨雷达一维距离像目标识别研究的具体思路,在此基础上,重点讨论了几种一维距离像的特征提取方法、分类识别方法及如何克服方位角变化对距离像的影响等雷达目标识别实现中的关键理论,对这些理论的深入研究将极大地促进雷达目标识别技术的发展.     

汉字识别研究的回顾

本文回顾了汉字识别研究的历史。根据模仿人类视觉模型，基于文字图像的统计模式识别方法是文字识别取得瞩目进展的基础。模式识别信息熵理论揭示了模式分类的信息过程和理论极限，本文讨论了从汉字图像中提取特征以及文字识别分类器设计和学习的各种方法。介绍了文本识别必须解决的文字切分，版面分析、理解和重构，及提高识别性能等重点问题，最后，总结了文字识别研究的重要进展和对今后的展望。     

混沌理论与雷达技术发展

混沌动力学作为研究非线性系统的一种新方法已引起雷达界的重视,混沌信号是一种类随机性信号,具有极强的抗干扰性和极低的截获概率。研究了混沌在雷达中的应用,分析了混沌理论在雷达波形设计、信号检测与估计、目标识别、及杂波分析与建模等领域内的发展情况,指出在雷达应用技术中引入混沌理论是雷达技术发展的必然趋势,并预测了混沌理论与雷达技术研究发展的前景。     

自动目标识别的工程视角述评

自动目标识别(ATR)是一个和信号与信息处理、模式识别、人工智能等学科密切相关的特殊工程技术应用领域。由于ATR系统识别对象固有的不确定性，识别环境的复杂性，以及日益加剧的识别对抗性，使得ATR的发展一直面临着从理论到技术、到应用的系统性挑战。该文从工程视角出发，阐述了ATR的定义与内涵，简要回顾与分析了该领域发展动态，梳理了ATR的核心技术体系与系统开发模式，最后对未来的发展挑战做了分析。      

基于小波和BP神经网络的无线电探测目标识别技术

目标识别是智能弹药研发的关键技术之一，本文采用小波变换和BP神经网络理论对无线电探测目标识别技术进行了研究，给出了分类识别算法，并用实测数据进行了实验验证，结果表明该识别算法具有很高的目标识别率．     

D-S证据理论方法在目标识别中的应用

D-S证据组合理论已经成为不确定性推理的一种重要方法,基于该理论的多传感器决策层数据融合已得到广泛应用.介绍了D-S证据理论及其有关概念和D-S合成法则,阐述了基于D-S证据组合理论的数据融合一般步骤及决策层判决方法,运用D-S证据理论对目标进行了融合识别.与单一传感器的目标识别结果相比较,上述方法能明显提高目标识别能力,同时降低目标识别的不确定性,提高目标识别的可靠性.     

小波分析在文字识别中的应用

小波分析是新兴的用于科学和技术领域中的分析理论,能够科学、迅速地解决文字信号、图像信号等信号在时空域中的分辨率和奇异性位置等问题,成为分析发展史上重要的里程碑。与此同时,随着社会的发展,行业信息传递、存储成为重要的工作内容,因而加强小波分析在文字识别中的应用,能够将信号更好地分解交织在一起,收集更为微小的信号细节,赋予信号更多突变点诊断能力。因而,文章从小波分析的相关发展入手,探究文字识别中分析的相关信息,从而进一步探究小波分析在文字识别中的应用,旨在提高小波分析的实践效能,提升文字识别在社会各行业发展中的积极作用,推动社会各行业中信号传送的发展。     

雷达

TN952008011692混沌理论与雷达技术发展/朱丽莉,张永顺,王冲(空军工程大学电讯工程学院)//现代雷达.―2007,29(1).―16～19.混沌动力学作为研究非线性系统的一种新方法已引起雷达界的重视,混沌信号是一种类随机性信号,具有极强的抗干扰性和极低的截获概率。研究了混沌在雷达中的应用,分析了混沌理论在雷达波形设计、信号检测与估计、目标识别、及杂波分析与建模等领域内的发展情况,指出在雷达应用技术中引入混沌理论是雷达技术发展的必然趋势,并预测了混沌理论与雷达技术研究发展的前景。图0表0参16TN952008011693目标微动特性研究进展/庄…     

多传感器目标的模糊识别

根据模糊理论，采用信息融合技术和模糊识别技术，讨论了在多类传感器网内进行多目标模糊识别的一般原理和方法。     

雷达目标识别技术及其新进展

从雷达目标识别技术作为现代雷达的一个重要发展方向出发，对雷达目标识别的几种主要方法即目标运动轨迹特征识别法、回波幅度起伏特性识别法、多频雷达回波识别法、极点识别法、斜升响应识别法和极化识别法等作了阐述，最后对雷达目标识别技术的新进展即波形综合法、雷达成象技术及神经网络在雷达目标识别中的应用作了展望。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.