多参数无线传感器网络监测系统设计

针对传统物理布线式的传感器数据采集监测系统布线繁琐、功耗大、结构单一、动态性能差等特点,设计了一种基于ZigBee技术、包含一个数据基站和多个多参数终端采集节点的无线传感器采集系统。采用低功耗、无线收发性能良好的CC2530作为系统节点和数据基站的主控芯片。通过Z-Stack协议栈和OSAL操作系统,实现了基于ZigBee的无线传感器网络的通信和组网。考虑到采集现场对不同信号的需求,该系统可同时采集数字信号和模拟信号。节点通过CC2530主控芯片的串行外设接口(SPI),采集数字化传感器输出信号;通过扩展AD7656实现6通道并行A/D转换,从而采集多个传感器输出的模拟信号。实测结果验证了系统的网络传输性能和动态拓扑结构,以及各终端采集节点对数字信号和模拟信号的采集性能。基于ZigBee的无线传感器网络技术优势突出,必将成为传感器信号采集行业的发展方向。     

基于MSP430F149的无线传感器网络节点设计

本文设计了以超低功耗单片机MSP430F149为核心,结合外围传感器和无线收发模块的传感器网络节点.MSP430F149控制传感器采集环境中的温度、振动数据,并对原始数据进行初步处理,再由无线收发模块将数据发送给相邻节点.数据经传感器网络节点的一级级转发最终发送回主机,实现对环境的监测.     

基于ZigBee协议的无线传感器网络设计

本设计以超低功耗单片机MSP430F149为核心,结合外围传感器和无线收发模块设计了传感器网络节点.MSP430F149控制传感器采集环境中的温度、振动数据,并时原始数据进行初步处理,再由符合ZigBee协议的无线收发模块将数据发送给相邻节点.数据经传感器网络节点的逐级转发最终发送回汇聚节点,再由它向监控计算机发送,实现对环境的监测.     

基于MSP430的无线传感器网络设计

简要介绍无线传感器网络,给出基于MSP430F1xx系列单片机的无线传感器网络节点制作及组网设计方案;结合射频收发一体的NORDIC系列芯片和新型数字传感器,设计可组建无线网络的探测节点,实现对监测区域内相关物理信号的采集;给出组网设计中相关技术研究。通过实验表明,制作的传感器节点在数据采集和传输过程中有较高的可靠性。     

无线传感器网络节点硬件的模块化设计

简要介绍了射频芯片CC2430的性能和特点,设计了一种基于CC2430的无线传感器网络节点硬件的模块化设计方案。该设计由控制模块进行节点的功能管理,采集模块负责数据的采集和调理,无线模块进行数据上传和命令的传达,电源模块提供并管理节点的各模块用电。     

SIM300和nRF24LE1的多通道无线数据采集系统设计

设计了由GSM/GPRS模块SIM300和射频收发芯片nRF24LE1组成的无线数据采集系统,实现了对数据的采集与无线传输。系统由嵌入高速单片机的nRF24LE1芯片完成对多路数据的采集、处理和收发,并由SIM300将数据通过网络传递给TCP服务器和手机终端。在完成系统的硬件设计和软件开发的过程中,重点探究了nRF24LE1芯片的多通道收发过程和TCP服务器的建立。该系统具有功耗低、扩展方便等优点,适合多种无线数据采集和传输的场合。     

无线视觉传感器网络的节点设计

无线视觉传感器网络将监测的环境信息拓展到视觉层面,实现更精细化的监测,引发国内外研究人员的诸多关注.针对无线视觉传感器网络的特殊性,以高性能嵌入式处理器为核心设计了无线视觉传感器节点硬件,包括微处理器模块、无线收发模块、视觉信息采集模块、电源管理模块等;软件程序支持采集环境视频并进行压缩处理,获取节点间距离和节点剩余电量参数,支持自组建Ad-hoc网络进行节点间无线通信、视频传输和节点参数交换等.实验验证表明,所设计的无线视觉传感器节点运行正常,节点间距离测算以及剩余电量获取满足传感器网络应用需求.     

nRF903无线通讯模块在无线数据采集系统中的应用

为了实现无线数据的采集，提出了一种基于nRF903模块的无线通信解决方案。讨论了无线收发芯片nRF903的用户接口功能及其配置，论述了利用过采样和UART两种方法实现无线数据传递的通信协议及其应注意的问题，给出了软硬件设计方法。利用无线通信模块实现无线数据采集系统中嵌入式主机和传感器节点之间的数据传输。     

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.     

井下实时监控无线传感器网络节点的设计与实现

针对煤矿井下环境在线监测的要求,提出了一种井下实时监控无线传感器网络节点的设计方法,详细介绍了无线传感器网络节点的硬件组成和软件设计。该节点通过微控制器和无线传输模块实时采集、处理、传输井下工作面的瓦斯浓度、CO浓度、温度、湿度等数据。测试结果表明,该节点控制方便、工作稳定,能实现可靠的无线网络传输。     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.