格非Magi1000自动播出系统主备数据库同步和快速切换

结合实际使用，简单介绍北京格非Magi1000板卡式硬盘自动播出系统主备数据库同步和切换的方法以及存在的不足，给出了用Delphi7．0编写主备数据库服务器快速切换软件的方法和关键代码，减少了维护工作量，确保播出系统安全不问断运行。     

一种基于北斗的伪卫星设计方案

文章针对导航卫星数目不足的环境下北斗导航定位设备的可用性问题,提出通过建立伪卫星调整星座构成来解决问题的一种思路,对伪卫星系统定位原理,及其主要问题和解决方案进行讨论和分析。     

谁为我的安全负责？

连续好长时间，笔者都在与很多学校的网络中心进行亲密接触，接触的时间久了，发现校园网的安全着实让人担忧，听到更多的就是：校园网，谁为我的安全负责？     

欧胜提供业内最低功耗 CODEC显著延长多媒体 便携设备的音乐回放时间

欧胜微电子于6月22日宣布推出型号为WM8961的超低功耗立体声编码解码器（CODEC），它是其新一代超低功耗器件系列的第二款产品，为极大延长便携设备音频回放时间而设计。WM8961以欧胜开创性的WM8903编码解码器为基础，在芯片中集成了同样的创新技术以及一个附加的内置高功率D类立体声扬声器驱动器。这项提升扩展了欧胜业界领先的超低功耗音频技术在要求高性能扬声器驱动器功能中的应用，其市场包括移动互联网设备（MID）、手持游戏机和便携媒体播放器（PMP）。     

陈国清升任巨橡总经理

巨橡企业今年营运明显转佳，近日董事会决议通过，董事长庄煌星免兼总经理；执行副总经理陈国清升任总经理，11月1日生效。巨橡也同步调整转投资江苏省昆山巨龙高阶复合材料人事案，陈国清也升任总经理。     

可收缩的牛奶壶 Fresh

通常来说，牛奶的保鲜时间大约是一个星期。不过，创新设计的可收缩牛奶壶Fresh可以让人们改变这样的传统观念。其实牛奶坏掉的主要原因往往是我们盛牛奶的杯子里面有大量的空气，是杯子里面的空气让牛奶迅速坏掉。如果使用这款可以收缩的牛奶壶，可以将牛奶盛到壶里后，根据牛奶的量，缩短壶的高度，将空气排出来，尽量让牛奶充满这个壶的空间，     

美国国家半导体推出全新系列高电压降压控制器，可提供高达75V的输入电压幅

美国国家半导体公司（National Semiconductor）宣布推出4款全新的高电压非同步降压控制器．其完备的功能特性主要包括：适用于极高的输入电压．可以提供卓越的脉；中宽度调制（PWM）控制．而且还可减少电磁干扰（EMI）。     

Optimization of listening time of S-MAC for wireless sensor networks

In wireless sensor networks, sensor nodes are usually battery-operated computing and sensing devices, hence operations are limited by the initially equipped batteries, which are hard to be recharged or replaced. In this sense, saving energy consumption becomes significant. As most energy waste is from the always-on wireless interface, S-MAC is suggested to reduce energy consumption by introducing periodic listen/sleep scheme. However, when designing the listening time, S-MAC fails to consider the traffic distribution factor. In this article, an optimization for this scheme is proposed based on the distribution model. Evaluations show that the optimized S-MAC achieves considerable improvement in energy and latency.     

Synchronization of different chaotic systems via active radial basis functions sliding mode controller

This paper presents a new method to synchronize different chaotic systems with disturbances via an active radial basis function （RBF） sliding controller. This method incorporates the advantages of active control, neural network and sliding mode control. The main part of the controller is given based on the output of the RBF neural networks and the weights of these single layer networks are tuned on-line based on the sliding mode reaching law. Only several radial basis functions are required for this controller which takes the sliding mode variable as the only input. The proposed controller can make the synchronization error converge to zero quickly and can overcome external disturbances. Analysis of the stability for the controller is carried out based on the Lyapunov stability theorem. Finally, five examples are given to illustrate the robustness and effectiveness of the proposed synchronization control strategy.     

Passive adaptive control of chaos in synchronous reluctance motor

The performance of synchronous reluctance motor （SynRM） degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in SynRM, a passive control law is presented in this paper, which transforms the chaotic SynRM into an equivalent passive system. It is proved that the equivalent system can be asymptotically stabilized at the set equilibrium point, namely, chaos in SynRM can be controlled. Moreover, in order to eliminate the influence of undeterministic parameters, an adaptive law is introduced into the designed controller. Computer simulation results show that the proposed controller is very effective and robust against the uncertainties in systemic parameters. The present study may help to maintain the secure operation of industrial servo drive system.