基于WSN的SimpliciTI协议移植和实现

SimpliciTI 协议是美国TI公司推出的针对简单小型RF网络的专有低功耗协议。在Keil MDK 3.8开发环境下移植 SimpliciTI 网络协议, 设计一种无线传感器网络系统, 系统包括中心节点和终端节点。该系统以单片机STM32F103C8作为微处理器, 通过控制射频收发芯片ADF7021进行数据的收发。通过对 SimpliciTI 网络协议及其拓扑结构进行了分析, 并在此基础上设计低功耗和载波侦听退避算法, 最终实现了基于 SimpliciTI 协议的无线传感网系统, 可用于单数据采集中心和多个传感器节点的场合。     

一种无线传感器网络低功耗节点的设计

节点的功耗大小决定着整个无线传感器网络的生命周期,因此,节点的低功耗设计尤为重要;在简单介绍分析各节点设计解决方案及其特点的基础上,分析了无线传感网络系统中低功耗节点设计方案、关键芯片选择、设计及其实现,重点阐述了低功耗控制设计及其实现方法,最后,完成了不同工作条件下的节点消耗电流测量和分析;实验结果表明,提出的节点设计方案在保证低功耗特性的同时,兼具良好通信性能.     

基于SimpliciTI协议的无线自组织网络系统设计

SimpliciTI协议是TI推出的针对简单小型RF网络的专有低功耗RF协议。采用SimpliciTI网络协议,设计了一种无线自组织网络系统。该系统采用CC430F5137作为微处理器,配合其内部集成的CC1101无线收发器以及一些基本接口电路构成节点硬件系统。网络系统包括中心节点、路由节点和终端节点,分别对SimpliciTI网络协议及其拓扑结构进行了分析,并在此基础上进行软件设计,最终实现了基于SimpliciTI网络协议的串状网络通信系统。     

无线传感网络温湿度采集系统的设计及实现

一直以来,低功耗以及远距离传输是无线传感器网络多点测量的两大不足,成为阻碍其进一步普及的瓶颈;利用无线传感网络分布式多点测量的特点,设计了基于IRIS节点无线传感网络的温湿度采集系统,介绍了系统整体框架和软件体系的设计及实现过程,并进行了温湿度采集实验;实验结果表明,节点可通过无线通信方式形成一个多跳的自组织网络系统,网络具有自愈功能,节点能够精确地采集和处理温湿度数据,节点间可以成功地进行通信,具有低功耗和远距离传输的优点.     

一种通过算法移植降低无线传感器网络能耗的方法

在研究了多种降低系统功耗方法的基础上,针对无线传感网络的低功耗要求,对无线传感器网络各模块进行了分析和研究,设计并实现了一种基于算法移植的软件开发低功耗的方法,有效降低了节点功耗.采用高性能无线传感器Imote 2节点进行实验,和原有方法进行了对比,并分析其功耗.结果表明:改进后的方法能有效地降低节点的能耗,延长了整个网络的生存期.     

一种低功耗无线传感节点设计

针对现有远程无线传感节点存在的功耗较高、测量准确度易受供电电压影响等不足,提出了一种基于时间同步的低功耗通信机制,采用比率测量技术、传感电路节能测量技术、无线SOC技术等技术设计了基于nRF24E1为核心的无线传感节点软硬件.实验表明,无线传感节点休眠功耗仅有2.45μA,10s采样周期的平均电流为93μA;既实现低功耗,也保证了测量准确度.     

基于无线传感网络的β辐射监测系统的实现

根据β辐射监测环境的特殊性和实际监测功能需求,以G-M计数管作为β辐射探测器,采用MSP430F1611单片机处理器和CC2530的无线收发器芯片的传感器节点设计,运用ZigBee无线传感网络技术于无线传感监测网络中,实现了一种新型的基于无线传感网络的β辐射监测系统,具有低功耗、自组网,监测数据高可靠性、稳定性好,覆盖度广等优点,应用前景十分广阔.     

一种低功耗无线传感器节点设计

介绍了一种基于STM8L152的低功耗无线传感器节点,阐述了节点微处理器、无线收发模块、和电源等硬件的低功耗设计,并对从软件上进行了低功耗设计,符合了构建无线传感器网络成本低、功耗低、体积小等需求。     

一种低功耗无线传感网络节点的设计

无线传感器网络是物联网的传感层。在无线传感器网络的设计与实现中,低功耗成为系统应用的重要制约,因此设计低功耗节点是当前研究难题之一。在自主研发的基于无线传感网络的智能交通系统中,研究电源功耗问题,设计并制作完成了低功耗无线传感网络节点。     

一种低功耗无线传感网络节点的设计

无线传感器网络是物联网的传感层。在无线传感器网络的设计与实现中,低功耗成为系统应用的重要制约,因此设计低功耗节点是当前研究难题之一。在自主研发的基于无线传感网络的智能交通系统中,研究电源功耗问题,设计并制作完成了低功耗无线传感网络节点。     

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.