UWB技术在移动Ad Hoc网络中的应用研究

目前移动Ad Hoc网络的研究越来越受到人们的关注。随着超宽带(uwB)技术的发展，将其应用到移动Ad Hoc网络也成为现实。文中首先概述了移动Ad Hoc网络及其两种应用形态，然后介绍了UWB技术的背景知识。着重提出了UWB技术在移动Ad Hoc网络中应用的可行性，阐述了该应用将会遇到的问题，并从路由协议、网络QoS保证、多址接入、网络资源管理、拓扑结构设计及功率控制等关键技术探讨UWB技术对移动Ad Hoc网络的影响，最后展望了基于UWB技术的移动Ad Hoc网络的应用前景。     

无线Ad Hoc网络中支持P2P应用的研究

无线Ad Hoc网络和P2P技术近年来发展迅速,已经成为宽带无线网络技术领域的研究热点.相关研究表明.在现有的无线Ad Hoc网络中直接应用P2P技术.会造成系统开销大量增加,分组传输效率及查询成功率下降,从而影响整个网络的性能.本文针对上述问题进行分析,采用跨层设计的方法,提出了在无线Ad Hoc网络中实现P2P应用的解决思路和方案,满足无线Ad Hoc网络中各种P2P应用的不同QoS需求.     

Ad Hoc网络

首先介绍了Ad Hoc网络的基本概念、技术特点以及关键技术等，然后较为全面地归纳了Ad Hoc网络的典型应用，最后讨论了Ad Hoc网络的发展趋势和有待解决的问题。     

Ad Hoc网络与Internet互联的实现

首先简单介绍了Ad Hoc网络的原理,然后介绍了Ad Hoc网络中应用的两种重要的路由算法,最后介绍了实现Ad Hoc网络与Internet互联的具体方案。     

基于ARM的嵌入式Ad Hoc网络平台的实现

Ad Hoc网络作为一种对等无线网络,在军事、传感器网络等众多场合有着极其重要的应用。当前关于AdHoc网络的理论成果已经非常丰富,但是在实际应用方面尚不成熟。本文以ARM嵌入式技术为基础,从硬件和软件两方面叙述了搭建一个AdHoc网络平台的过程。经测试证明,该平台实现了AdHoc网络节点的功能,同时具有移动、便携等优点,具有较强的应用价值．     

Ad Hoc网中IP地址分配技术综述

文章详细介绍了目前用于Ad Hoc网络中IP地址分配的几种典型技术的原理和实现方法，分析了各种技术的优点和不足之处以及其适用范围。从通信开销、收敛速度和可扩展性等方面比较了各种技术的相关性能。最后总结了实现Ad Hoc网络中IP地址分配需注意的几个要点，并指出了Ad Hoc网络中IP地址分配技术今后的发展方向。     

移动Ad Hoc网络组播路由协议的研究综述

移动Ad Hoc网络是一个自组织、移动节点通过无线链路组成的动态拓扑变化的网络。由于网络规模小、无基础设施构建快速等特点,从而广泛应用于灾难救助、临时会议、战场指挥等场合。这些应用都涉及到移动Ad Hoc对组播的支持,因此,随着网络应用规模的增长,移动Ad Hoc网络对组播的支持成为一个重要的研究课题。本文对目前的组播路由机制进行了分类和研究,详细描述和比较了这些移动Ad Hoc网络组播路由协议,为组播路由协议和算法进一步的研究提出了新的课题。     

Ad Hoe网络的复合安全策略研究

在总结了Ad Hoc网络的安全问题的同时,对Ad Hoc移动通信网络的身份加密技术（IBE）、网络分组技术、Ad Hoc网络信任评估技术进行了大量的研究,试图提出一种新型的Ad Hoc移动通信网络的安全策略,这种新的网络安全策略降低了Ad Hoc移动通信网络资源的开销。文中给出的网络安全策略的仿真,仿真表明：该安全筹略有效地保证Ad Hoc网络路由信息不被伪装、攻击、重播,加强了整个Ad Hoc移动通信网络的安全性能。     

Ad Hoc网络的复合安全策略研究

在总结了Ad Hoc网络的安全问题的同时,对Ad Hoc移动通信网络的身份加密技术(IBE)、网络分组技术、Ad Hoc网络信任评估技术进行了大量的研究,试图提出一种新型的Ad Hoc移动通信网络的安全策略,这种新的网络安全策略降低了Ad Hoc移动通信网络资源的开销.文中给出的网络安全策略的仿真,仿真表明:该安全筹略有效地保证Ad Hoc网络路由信息不被伪装、攻击、重播,加强了整个Ad Hoc移动通信网络的安全性能.     

基于泛搜索路由协议的Ad Hoc网络设计与实现

在Ad Hoc网络技术的工程实现中,路由协议的选择以及硬件无线通信系统设计是要解决的两个关键环节。本文针对节点之间无等级结构的Ad Hoc网络,基于一种泛搜索路由协议进行Ad Hoc网络系统设计和实现。硬件通信设备采用单片机C8051F920控制无线数传模块的方案进行设计,按照搜索路由协议对单片机编写程序,继而组建Ad Hoc网络系统。通过对网络测试所得的数据结果进行分析,表明该路由协议能适应网路拓扑结构变化,准确地找到一条适合传输的路由,所设计通信系统满足Ad Hoc网络的基本特征。     

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.