用于环境监测的无线传感器网络节点的设计与实现

无线传感器网络具有很强的应用相关性,在不同应用要求下需要配套不同的硬件平台和软件系统.以核化污染区域环境和气象环境监测为应用背景,以温度和湿度等为检测参量,设计并研制无线传感器网络小型节点.实验测试表明节点能够有效地采集和处理数据,并可以在节点闻成功地进行通信.     

基于PSoC的无线传感器网络节点设计

无线传感器网络节点的优劣直接关系到无线传感器网络的生存周期及其传递的数据的可靠性.用PSoC(可编程片上系统)作为处理器模块的处理器,运用于无线传感器网络节点的设计之中,使无线传感器网络节点降低功耗,缩小体积,提高可靠性,降低成本,增加生存周期,缩短开发周期.论文首先简单介绍了PSoC独特的内部资源及其特有的功能,然后详细阐述了采集环境的温度和湿度的无线传感器网络节点的硬件电路和处理器模块的软件设计方案.最后给出了实验结果,其实测结果表明设计的传感器系统性能良好.     

基于无线传感器网络的井下温度监测系统设计

针对目前矿井温度监测的现状,设计了一种基于无线传感器网络的矿井温度监测系统,该系统以C2430芯片为核心设计传感器节点,以CC2430和MCP2515设计Sink节点,给出了系统的硬件设计和软件流程。该系统克服了传统有线网络的局限性,避免了其他无线通信技术高功耗的缺点,简单、可靠、经济,具有很好的应用前景。     

一种用于农业环境监测的无线传感器网络设计

提出一种应用于农业环境信息监测的无线传感器网络,实现对农业试验田温度、湿度及光照强度的实时监测。处于同一个网络的节点通过点名和轮询机制,实现网络的建立与维护。传感器节点实时地获取所处环境的温度、湿度和光强信息。用户可根据需要查询相应的信息。实验结果表明：该网络能够实现所需信息的获取和传输功能。     

基于CC2430的无线温度变送器设计与实现

嵌入式系统和无线通信技术的发展,为无线传感器网络的工业应用提供了技术支持。本文基于ZigBee协议,以无线温度变送器的设计为实践背景,从硬件和软件两个方面介绍采用K型热电偶、CC2430嵌入式系统来研发无线变送器的方法,讨论无线传感器网络终端节点的组成结构、实施技术,分析其核心模块的设计和实现细节。     

基于无线传感器网络的温度监测系统

无线传感器网络是传感器领域内一个新兴的研究方向,可以在一些特殊的场合实现信号的采集、处理和发送。该文介绍了一个基于无线传感器网络的温度监测系统。其节点以8位AVR单片机AT-mega128L为核心,结合外围传感器和无线收发模块cc2420芯片,实现了对温度的监测。系统采用ZigBee无线通信协议,功耗低、性能稳定。     

基于无线传感器网络的环境参数测量仪设计

基于无线传感器网络设计了环境参数测量仪,传感器节点采用超低功耗的CC2430射频芯片,并移植了完全符合ZigBee 2006标准的协议栈,在协议栈上运行数据采集应用程序,能够实时地采集周围环境的温度和湿度等环境参数,并将数据通过无线传感器网络传输给与之相邻的路由节点,最终实现多点参数采集;主要对传感器节点的软硬件设计进行了介绍,硬件方面重点介绍了数据采集模块、电源模块的接口设计;软件方面重点介绍了节点程序的设计过程,并以AD转换模块为例,给出了一个应用程序组件中配件和模块的软件;该设计硬件简单可靠,软件编程容易,可方便的移植到其它控制系统中,经测试具有良好的测量精度和实时传输功能.     

基于WSN的小区自行车防盗系统的设计

针对小区管理的需求,将无线传感器网络引入到小区自行车防盗系统中.以ATmega128L单片机为核心扩展了断线检测模块和以CC1000芯片为基础的无线通信模块,设计了无线传感器网络的电子锁节点和Sink节点.规划了无线传感器网络拓扑,设计了具有较高稳定性的简单无线通信协议,基于监控主机以多线程的方式实现了防盗监控软件.实验验证了方案的可行性,仿真验证了多节点情况下,通信协议的稳定性.     

基于CC2430的无线传感器网络节点设计

基于无线传感器网络的特点,以CC2430芯片为核心设计了一种微型传感器节点。详细阐述了传感器节点的温湿度数据采集模块、电池能量检测模块以及节点之间"点对点"无线通信的软件流程。     

一种温度自适应无线传感网络时间同步方法

无线传感器网络节点中的廉价晶振极易受到温度、电压、湿度等工作环境因素的影响.节点晶振的这一特性,为室外大规模无线传感器网络时间同步技术带来了两方面的挑战:(1) 过高的通信开销;(2) 精度与能耗之间的不平衡.针对以上问题,提出了一种基于温度感知的、自适应的无线传感器网络时间同步算法.该算法能够依赖本地温度信息对节点时间频偏进行估计及补偿,在保证算法同步精度的同时,降低了网络通信开销.除此之外,提出一种动态同步周期调节机制,使得算法能够根据当前环境温度变化情况对节点同步周期进行动态调节,从而达到了能耗与精度之间的平衡.大量仿真实验结果表明:所提出的时间同步算法可将通信能耗降低至传统同步算法的10%;且在环境温度不断变化的情况下,80%的频偏估计值其误差小于0.5ppm.故,所提出的时间同步方法能够有效地适用于室外环境下部署的大规模无线传感器网络.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。