多对多通信

Generated by lightning impulse testing system are used to test many kinds of electrical devices and insulation materials,such as SPD,lightning arrester,etc.

0引言雷电冲击测试系统广泛应用于电力系统、通信系统、邮电系统、输变电设备和电子元件生产企业以及铁道部门等，其产生的冲击电压(1.2/50μs等波形)、冲击电流(4/10、8/20、10/350、10/1000μs等波形)用于对诸多电气设备和绝缘材料，如SPD、避雷器等进行雷电冲击试验，也可以进行冲击联合试验等科学试验。

Following are the main results of this thesis: Detailedly analyze some related schemes concerning group key management, We reconstruct a tree key management scheme, in comparison with Logical Key Hierarchy and One-way Function Tree schemes, we find that it has good performance of key storage, re-key communication costs and calculation of group manager.

本论文的主要研究成果如下：对目前存在的多播组密钥管理方案进行了详细的研究分析，提出了一种改进的树型管理方案，与逻辑密钥分层方案和单向函数树方案进行分析比较，它在密钥存储、密钥更新、通信量以及组管理者的计算量方面均有较好的性能。

The logical framework approach,the comparison approach and the success degree approach are demonstrated with examples.

在此基础上，结合后评价实践，对包括逻辑框架法、对比法、成功度法等的通信工程项目后评价常规方法进行了分析和比较；为解决后评价指标权重分配、定性指标定量化、多指标评价结论综合汇总等问题，提出了基于语义判断和模糊判断的综合后评价方法。

As mobile communication technology advances, especially in 3G networks and wireless local area network continues to mature, the mobile library system is being constantly progress and development, in the process a considerable number of new features and applications, this article seeks to move from the status of the library system, the era of 3G mobile wireless networks the development of the library system on.

随着移动通信技术的不断进步，特别是3G网络和无线局域网的不断成熟，移动图书馆系统正在不断地进步和发展，在此过程中出现了相当多崭新的功能和应用，本文力求从移动图书馆系统的现状出发，对3G无线网络时代的移动图书馆系统的发展进行阐述。

The data needs to be transferred from testers to the host computer in the testing system for real-time acceleration. For the sake of improving the controlled at real-time and the reaction rate of accepter for data, at the condition of Windows XP, the serial communication between signal PC and multistation of sensors was realized and the data collected by each sensor can be got at real time.

在实时加速度测试系统中，数据需要从测试仪传送到主机上，为了提高控制的实时性及接受端对数据的反应速度，利用VC++7.0下的Active控件和RS-232串行接口，实现了在Windows XP环境下，单台PC机与多台传感器的串行通信，并能实时获取各传感器的数据采集。

Each layer has one or more protocols for communicating with its peer at the same layer.

每层都有多个协议在同一层内和对端相同协议通信。

This quadrature approach is of theoretical and practical value for the application of Radar and EW.

该正交采样技术利用多速率信号处理方法，可对ADC基带采样率内的任意带通信号得到其调制复包络输出，并具有很好的镜像抑制，在雷达和电子对抗信号处理中具有其实际的理论和应用价值。

With the development of communication and network technology, more and more control systems are connecting with State Power Data network. Especially the power market is being put into operation, and more data are exchanged. The control system and data network face a big challenge about security, reliability and real time operation.

随着通信技术和网络技术的发展，接入电力调度数据网的控制系统越来越多，特别是电力市场的发展，数据交换非常频繁，这对电力控制系统和数据信息网络的安全性、可靠性和实时性提出了新的挑战。

This paper describes realization software of the servosystem detaily.

三、详细介绍了系统软件的各个模块功能，包括DSP内部资源分配，数据的规格化处理；调节器的设计、控制策略及实现；转子磁极位置检测；通信等多个模块，从而实现对永磁同步电机的定位控制。

The optimum detector and a class of suboptimum detectors for the synchronous SSMA system are discussed in this paper.

对同步多址扩频通信系统中的最优检测器和某些准最优检测器进行了讨论。

I am sure after a few weeks of adaptation and familiarization I will have no difficulty in functioning on a daily basis in an English speaking society or in participating fully in graduate studies.

在大学的三年的学习生活不仅给予我自身的充实，更重要的是磨练和培养了我较强的自觉能力和严谨，踏实的作风以及不怕困难的精神，对未来充满了信心！

As the first volcanoes erupted, one of the gases that bellowed out was steam.

在第一批火山喷发时，喷出的气体之一就是水蒸汽。