面阵列封装器件的贴装技术

面阵列封装器件在电子产品中的使用率逐年上升，如何实现其高速贴装是影响生产线效率的重要因素。从不同的角度论述了面阵列封装器件实现高速贴装的手段与技术。     

图像压缩编码方法分析

介绍图像压缩编码技术发展过程,对图像压缩编码,特别是自适应预测编码、模型法编码、分形编码、小波变换压缩编码、神经网络压缩编码原理和特点进行分析,并阐述图像压缩编码的作用.     

智能同步光网络与多业务传送平台的应用

智能同步光网络(ASON)与多业务传送平台(MSTP)固其先进的智能性、可靠性、灵活性而得以发展和运用。本文根据智能光网络与多业务传送平台枝术的发展情况，结合北京通信传送网络的实际情况，探讨北京通信传送网的建设思路．     

Modeling and performance analysis of IP access interface in optical transmission networks with packet switching

The article analyzes the influence of the Internet Protocol (IP) access interface on the packet loss probability and delay times in the optical packet switched network. The network and node model have been proposed, and the structure of the IP access interface, including assembler and holder, have been included in the analysis. It has been shown that the increase of the maximum optical packet sizes, as well as use of the holding feature as contention resolution mechanism, decrease the packet loss probability, but introduce delays at the optical network access points. Modeling and analysis were based on the discrete event simulation assuming self-similar traffic sources. IP packet lengths were modeled using empirical data. This work has been conducted while the author was affiliated with the Telecommunication Laboratory, Swiss Federal Institute of Technology (EPFL-STI-ITOP-TCOM), Lausanne, Switzerland     

电信网络管理的望族——TMOS

电信管理及运营支撑是爱立信公司为公用电信网提供的有关管理及运营支撑功能的综合方案，本文介绍了其中的公网管理系统和蜂窝移动网络管理系统。     

网络安全技术研究

网络安全问题已经成为网络发展中急需解决的问题。已经引起人们的重视。给出了网络安全的概念，网络所面临的威胁，提出了解决网络安全的相关技术。     

地域通信网中基于业务量的动态路由研究

本文从地域通信网的特点出发，分析了以前所使用的路由选择方法的优缺点，提出了网控支持的基于业务量的动态中币管理方法，并描述了该路由管理方法的分层结构和在地域网网络管理系统中的具体实现。     

江苏省C3本地电话网组网方式探讨

本文结合江苏Ｃ４本地网的实际情况，说明Ｃ４本地网纳入Ｃ３本地电话网的必要性，例举了４种Ｃ３本地网的组网方式。     

SPAR: stochastic programming with adversarial recourse

We consider a general adversarial stochastic optimization model. Our model involves the design of a system that an adversary may subsequently attempt to destroy or degrade. We introduce SPAR, which utilizes mixed-integer programming for the design decision and a Markov decision process (MDP) for the modeling of our adversarial phase.     

A variable rate multipulse speech coder for CDMA cellular systems

Variable Rate (VR) speech coders are classified into: source-controlled VR coders where the rate is selected depending on the local character of the speech, and network-controlled VR coders where an external control signal selects the coding rate. The first category benefits from the variable rate channels used by Code Division Multiple Access (CDMA) mobile communications. The second category is indispensable for the right behaviour of the CDMA systems under conditions as high traffic levels. The VR speech coder presented in this communication exhibits both types of control. The source control is achieved by means of a Voice Activity Detector (VAD) and a phonetic classifier. The network control acts on the selection procedure of the multipulse excitation sequence to the synthesis filter. This is the main advantage of our VR MultiPulse speech coder because by means of an external signal the bit rate can be changed only every 4 msec, without transitions or distortions. Considering one-way communication, six different operating rates can be externally selected ranging from 4.8 to 9.1 kbps for the active frames; an average bit rate of 380 bps is required for the noise frames.This work has been partly funded by the Spanish Research National Plan under grant no. TIC92-0800-C05-02 and by Northern Telecom.