Summary of the First Generation High Temperature Superconducting Wire： Processing, Characterization and Applications

Silver-clad （Bi,Pb）2Sr2Ca2Cu3O10＋x long wires produced by powder-in-tube techniques, which have been recognized as the first generation of the High Temperature Superconducting （HTS） wires, are expected to apply widely especially in strong current applications. In this work, the processing, characterization and application of the silver-clad （Bi,Pb）2Sr2Ca2Cu3Ol0＋x HTS wires are summarized. The HTS wires are fabricated using the combination of powder-in-tube technique, and the resulting wires are fully characterized by the means of chemical analyses, microstructural observation, electrical and magnetic measurements. The relationship among fabrication parameters, chemical and microstructural characteristics, and electrical and magnetic properties are analyzed. Applications of the HTS wires have also been introduced according to their strong current behaviors with various prototype devices made.     

Large-Scale Traffic Characterization of Chinese Multimedia Messaging Service Using Hadoop

Recently, there have been many mo- bile value-added services in the Chinese mo- bile telecommunication market nowadays. Am- ong them, the characteristics of Multimedia Mes- saging Service （MMS） have not yet been fully understood. In this paper, with the help of a cloud computing platform, we investigated the flow-level charactefistcs of Chinese MMS. All of the experimental data were collected by the TMS equipment deployed in a major node in Sou- them China. The collection time spanned six mo- nths. We performed high-level analysis to show the basic distributions of MMS characteristics. Then, by analysing the detailed MMS features, we determined the distribution of personal MMS, and made a comprehensive comparison between 2G and 3G MMS. Finally, we tried to build a model on the personal MMS inter-arrival time, and we found that the Weibull distribution was optimum.     

机动车辆磁像识别技术在交通控制中的应用

根据交通控制中信息搜集的需要，提出了以磁像识别系统作为道路信息的采集探测器构建交通控制系统的方案，并说明了其工作原理和在实际应用中的可行性。     

An Approach to Scheduling Bursty Traffic

The scheduling scheme in packet switching networks is one of the most critical features that can affect the performance of the network. Hence, many scheduling algorithms have been suggested and some indices, such as fairness and latency, have been proposed for the comparison of their performances. While the nature of Internet traffic is bursty, traditional scheduling algorithms try to smooth the traffic and serve the users based on this smoothed traffic. As a result, the fairness index mainly considers this smoothed traffic and the service rate as the main parameter to differentiate among different sessions or flows. This work uses burstiness as a differentiating factor to evaluate scheduling algorithms proposed in the literature. To achieve this goal, a new index that evaluates the performance of a scheduler with bursty traffic is introduced. Additionally, this paper introduces a new scheduler that not only uses arrival rates but also considers burstiness parameters in its scheduling algorithms.     

神经网络在ATM流量控制中的应用

以ATM流量控制的三层结构模型为基础，介绍神经网络在接入允许控制（CAC）中的五种算法——学习控制方法、hybrid允许方法、移动窗口训练方法，BPHT算法和时间-差分学习方法。讨论基于神经网络的流量测量、流量管理和拥塞控制方法。性能分析结果表明神经网络提供了快速、自适应、简单的智能控制。     

基于地域通信网流量攻击方法的仿真研究

地域通信网中各节点之间的正常通信是保障作战胜利的关键,由于地域通信网中各节点间的连接多采用无线链路,可以使用流量攻击的方法对链路进行攻击,使各节点通信中断。在分析流量控制和拥塞控制的基础上,结合OPNET仿真软件建立网络模型,通过仿真研究验证了流量攻击法可以有效地使地域通信网通信中断,达到攻击的目的。     

基于流量强度的DDoS攻击源追踪快速算法

DDoS攻击以其破坏力大、易实施、难检测、难追踪等特点,而成为网络攻击中难处理的问题之一。攻击源追踪技术是阻断攻击源、追踪相关责任、提供法律证据的必要手段。基于网络拓扑理论和路由器流量特性原理以及可编程式路由器的体系结构,提出了一种追踪DDoS攻击源的分布式快速算法,该算法可以准确、协调、高效地判断路由器的数据流量值,受害者可以根据流量强度推断出恶意攻击数据流的来源,从而快速追溯和定位DDoS攻击源。     

基于区分服务的IP-UMTS视频传输QoS机制

为了满足在以IP作为骨干网协议,以通用移动通信系统(UMTS)作为接入网的异构网络环境中视频传输的服务质量要求.提出了基于区分服务的视频传输服务质量机制,给出了区分服务业务等级到视频数据帧和区分服务业务等级到UMTS业务类别的映射关系.使用仿真的实验环境对给定的服务质量机制进行了测试,实验结果表明该服务质量机制能有效地提高IP-UMTS异构网络中视频传输的服务质量.     

工业自动化中基于电话线的数据通信网络

结合实例探讨了如何利用工业控制计算机,在传统电话通信网络的基础上加入调制解调器构建计算机通信网络,可以访问远程计算机并采集数据,实现工业自动化.这种通信网络适应面广、实现简单而且花费低廉.     

重尾ON/OFF源模型生成自相似业务流研究

因为传统模型没有考虑网络业务流量各种时间尺度都具有突发性,因此是不完善的,一系列的测量结果表明,网络业务流量显示自相似性,重尾分布ON／OFF模型能比较好地解释自相似业务流的产生原因,可以把LAN上的业务分解为多个活动（active)主机对之间的业务流,本文通过系统的仿真实验研究了重尾ON／OFF源模型生成自相似流的机理,并与理论结果进行了对比,而且补充了理论结果。     

基于3G通信的智能交通关键技术研究

通过将3G移动通信技术应用于智能交通指挥控制系统,并利用发展迅速的3G移动通信网组成3G无线局域网来传输各交通路口信号点的视频和控制信息,为智能交通指挥系统组网提供了一条新路。