Blind channel estimation and equalization in wireless sensor networks based on correlations among sensors

In densely deployed wireless sensor networks, signals of adjacent sensors can be highly cross-correlated. This paper proposes to utilize such a property to develop efficient and robust blind channel identification and equalization algorithms. Blind equalization can be performed with complexity as low as O(N/spl tilde/), where N/spl tilde/ is the length of equalizers. Transmissions can be more power and bandwidth efficient in multipath propagation environment, which is especially important for wideband sensor networks such as those for acoustic location or video surveillance. The cross-correlation property of sensor signals and the finite sample effect are analyzed quantitatively to guide the design of low duty-cycle sensor networks. Simulations demonstrate the superior performance of the proposed method.     

Network traffic prediction based on a new time series model

Fast and accurate methods for predicting traffic properties and trend are essential for dynamic network resource management and congestion control. With the aim of performing online and feasible prediction of network traffic, this paper proposes a novel time series model, named adaptive autoregressive (AAR). This model is built upon an adaptive memory‐shortening technique and an adaptive‐order selection method originally developed by this study. Compared to the conventional one‐step ahead prediction using traditional Box–Jenkins time series models (e.g. AR, MA, ARMA, ARIMA and ARFIMA), performance results obtained from actual Internet traffic traces have demonstrated that the proposed AAR model is able to support online prediction of dynamic network traffic with reasonable accuracy and relatively low computation complexity. Copyright © 2005 John Wiley & Sons, Ltd.     

China＇s Electric Power Reform：Different Economics and Challenges

China＇s electric power reform has followed the western reform format, however, it doest not seem to have endorsed the liberalization ideology underlying the reform model. This raises the concern of whether and how a competitive power market may be established and reform objectives reached. The new market competition model is easy to build in theory. The experience of many countries suggests that the market reform is extremely difficult because of the interruptions by different interest groups. To transform a centrally planned power sector into a competitive power market is a daunting task. Policy makers need to take into consideration the transitional nature of the economy and power industry as they implement the competitive power market model.     

不锈钢精密薄壁件外表面磁力研磨工艺研究

磁性研磨是一种利用磁场中的磁性磨料,对具有相对运动的工件表面进行光整加工的新技术。选择铝、镍、钴磁粉作为磁性磨料时,对奥氏体不锈钢精密薄壁件外表面具有良好的研磨作用。     

齿轮减速器造型设计与模态分析

讨论复杂结构的建模方法,建立齿轮减速器三维实体模型并进一步建立了齿轮减速器的三维有限元模型,分析系统的固有特性,从而获得了设计所需的必要数据。     

电子政务建设若干经验与问题探讨

介绍世界电子政务的发展状况,在总结各国电子政务发展经验和特点的基础上,指出我国要建设优质、高效的电子政务的关键,是要树立转变观念、统一规划、分步实施的建设理念.     

矿用扁平接链环静态电测实验及有限元分析

对φ30的矿用扁平接链环进行静态拉伸电测实验，分析并得出产生最大强度的位置。同时应用ANSYS有限元分析软件对接链环的力学简化模型进行分析，与实验结果相比较，有助于找出齿部破坏规律，对齿形的改进及今后的疲劳分析具有重要意义。     

“业主想要的，又是业主没想到的”

大约1年前，接到陈怡姝在深圳某会的讲稿，题目是“互动设计”其内容简言之：在设计全过程中，业主的要求和建筑师的专业技能不断磨合，使建筑设计不断升华，达到一定水准。互动设计可能就是他们不断赢得业主，占有一定市场的原因。而今又读了她的“适度技术、本质设计”的文章。我的体会是，“适度技术，本质设计”是互动设计理念在飞亚达高科技大厦工程中的具体化，正如文中所说，适度设计与本质设计与投资方达成共识，在造价经济、功能合理的基础上表达理性，务实的理念。     

非标准工况下空分设备增产氩的研究与实践

文章对非标准工况下的空分设备增产氩措施进行了研究。以宝钢6#60000m3/h空分设备为例,通过设计型算法和校核型算法,建立了空分设备精馏的数学模型,通过改变数学模型的参数,分析了在非标准工况下精馏塔内的组分浓度分布,并提出了优化后的操作方案和操作参数,实施后提高了空分设备的氩提取率,取得了显著的经济效益。     

基于IPC的直流电机控制实验装置设计

介绍了工业控制计算机（IPC）在工业自动化领域中对直流机控制的应用，以工控机作为实验平台。设计了IPC测控系统之一的直流机测控子系统的实验装置，叙述了如何用IPC进行直流机转速的脉冲调宽式（PWM）控制，并通过软件实现在多任务实时操作系统（MROS）申直流机的速度测控和速度曲线绘制。