基于Sniffer的安全分析

Sniffer网络分析器是一款功能非常强大的协议分析软件支持的网络协议非常丰富，而且可以进行解码分析。利用Sniffer的强大功能，可以解决很多问题。     

基于Socket的网络编程技术及其实现

科学技术的不断发展推动了网络信息化时代的发展,随着计算机技术不断的发展,各种网络编程技术日新月异。本文介绍了Socket网络编程的基本概念,以及实现Socket编程的基本原理,通给出一个基于TCP协议实例,来说明实现网络编程。     

面向TCP/IP网络编程实验平台的设计

为了更有效地开展网络编程实验,设计了一个面向TCP/IP的网络编程实验平台,通过对网络编程中的标准函数进行封装,采用模块化的设计思路,降低了网络编程实验的开展难度。对网络编程实验平台的组成及功能实现进行了详细阐述,重点研究了网络编程实验平台中的标准函数开发接口,给出了网络编程的应用过程。平台设计合理,通用性强,通过简化网络编程中的程序代码,使得实验者能够集中精力从事特定的功能代码开发,更有效地辅助用户进行网络编程的实验,具有良好的应用价值。     

虚拟机环境下基于Sniffer的ARP协议结构研究

ARP协议是工作在数据链路层的网络协议,Sniffer是用于网络嗅探和协议分析的工具软件。为直观地观察研究ARP协议结构,设计了一个虚拟机环境下通过Sniffer研究ARP协议结构的实验。实验方法和结果对研究学习ARP协议有积极意义,也为后续的网络攻防研究打下基础。     

北京数据通信技术总公司提供先进的Sniffer网络分析仪和网络安全保护方案

北京数据通信技术总公司是信息产业部数据通信科学技术研究所组建的 ,是北京市新技术产业开发试验区的高科技公司 ,主要研究、开发、销售数据通信网络产品。本公司提供的网络设备及测试仪表等已广泛应用于中国国家数据通信网及许多省网及地市县级网络之中。　　 Sniffer网络分析仪　 Sniffer网络分析仪是美国Network Associates公司 (简称 NAI)研制的最新一代网络测试设备。它是在便携式或笔记本式微机上配上各种局域网或广域网模块以及丰富的测试软件构成的 ,广泛适用于Ethernet,Fast Ethernet,Token Ring,switched L ANS,FDDI,X.…     

短波宽带天线匹配网络的设计

本文基于统计学习理论构造了一种快速自适应随机搜索算法,证明了算法的收敛性。给出了一种简易实用的宽带天线匹配设计新方法。应用该自适应算法进行天线匹配设计,不仅算法简单,易于编程实现;而且能够快速设计出具有较好性能的匹配网络,非常适用于各种短波、超短波天线的匹配设计问题。     

基于有权图的网络最大流标号算法的研究与实现

本文首先总结和回顾了基于有向图的网络最大流的经典算法——标号法,并在算法思想的基础上,结合JAVA语言程序的设计流程,给出了标号法的计算机程序设计的步骤和部分代码实现。最后,通过具体的网络最大流应用案例,给出了求解网络最大流的具体步骤和编程测试结果。以此说明了标号法在解决此类问题中的具体用法,也验证了编程代码的可行性。     

交换式网络中监听技术的原理及实现

在网络中进行监听是维护、管理网络必须进行的操作。现如今,很多的局域网都已经换成了交换式网络,由于Sniffer监听的原理限制,在交换式网络中不能实现监听。论文详细阐述了网络监听的原理,在交换式网络中实现网络监听的技术和应用,并检测和防范网络中存在的监听。     

Delphi环境下用Socket实现Web服务器

WindowsSocket规范是在Windows下进行网络通信编程的API接口 ,也是Windows网络编程的事实标准。文章简要介绍了Socket原理、Delphi网络编程中的ServerSocket控件及HTTP协议 ,并给出了在客户机 /服务器模型下用Delphi 6 .0实现Internet中常见的Web服务器实例     

NOVELL网点对点网络通信程序设计——Windows下使用NetBIOS协议

本文讨论NOVELL网络Windows下使用NetBIOS协议进行网络点对点通信的编程技术。根据Windows和DOS下编程的不同方法,说明了Windows下编程的基本方法,并给出了一些实用的程序段,最后列出了发送方和接收方实例的流程图     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.