一种土壤湿度测定方法在Zig Bee无线传感器网络中的应用

农业无线传感器网络(WSNs)的终端节点存在着低功耗和低成本的要求,而现有的土壤湿度传感器难以满足这种要求.提出一种将土壤电阻传感器和土壤温度传感器的数据进行融合的方法,并利用多元线性回归和BP神经网络建立了土壤湿度的测定模型.该方法在实际的Zig Bee农业无线传感器网络中得到应用.实验结果表明:在同一种类型的土壤中,该方法测定土壤湿度的精度可达±2.5 ％RH,可用于实际农业大田的土壤湿度测定.     

多参数空气质量检测仪的硬件电路设计

在分析公共场合空气质量的基础上,研究开发了一款以MSP430为核心的气体检测仪。介绍了该系统的硬件电路实现方法。该系统以低功耗MSP430F2252单片机为核心,选择高精密传感探头,多种传感探头协同工作,可完成多种污染源的检测;对检测电路、信号处理电路以及反馈电路进行了设计和改造;系统检测的数据可通过液晶显示,通过存储电路存储及查询,数据超限时还可通过报警电路声光报警。经实验验证,系统具有低功耗、数据精确可靠、性能稳定、方便携带以及价格低廉等优点。     

基于单片机的低功耗甲烷检测系统设计

本文开展了作为电子鼻硬件平台的气体传感器阵列测试系统和高灵敏度甲烷检测系统的研究.研制成功的低功耗高灵敏度甲烷检测系统具有低功耗、智能化的特点,采用电池供电,LCD显示和USB接口,操作方便.检测仪硬件由微结构金属氧化物气体传感器阵列、气体进样装置及高速SOC单片机为核心的信号处理电路组成.在硬件设计中,着重于低功耗电路的设计,采用低功率器件和省电管理模式,使整个系统的工作功率低于1.5 W.     

嵌入式系统的低功耗调度算法研究

嵌入式系统的低功耗调度算法是嵌入式低功耗技术研究的重要研究方向,文中研究了一种任务间存在依赖关系的嵌入式系统的低功耗调度算法,建立了该低功耗调度算法的数学模型,由于模型的求解复杂性,结合嵌入式系统低功耗调度流程,通过一种比较简单的分步式思想,方便地求解了该低功耗调度算法的数学模型;建立了一个有6个任务的有依赖关系的任务集,通过该调度算法,对该任务集进行了调度,调度后的算法与调度前的算法对比降低的该任务集的能耗;最后用VC编程语言编程仿真验证了该低功耗调度算法的低功耗特性.     

基于LabVIEW和MSP430的CO气体无线监测系统设计

为了准确快速测量空气中CO的含量,介绍了一种基于LabVIEW和MSP430的CO气体无线监测系统的设计与实现;该系统通过红外气体传感器LHI814采集得到浓度数据.采用MSP430F149作为微处理器从传感器中读取数据,再将数据通过RS-232串口传送给ZigBee模块,然后通过ZigBee网络将数据传送给计算机,最后利用LabVIEW程序对数据进行处理分析以及显示、存储、回放与打印并进行声光报警等;该系统具有低功耗、高精度、设计简单、操作方便、界面友好及可靠性好等特点.     

基于ARM的蓝牙实时数据采集系统的设计

本文提出了一种基于ARM的蓝牙无线数据采集系统.结合嵌入式技术与蓝牙技术的优势,解决了传统工业现场数据采集系统中无法同时满足低功耗、低价格与高性能,并受到电缆布线限制和使用不便等问题.采用蓝牙无线通信技术来实现数据的采集,使得数据的采集和远程监测更为简单和方便,并且提高了数据采集的抗干扰性能.     

GPS时间同步的无线多点爆破振动监测系统

提出一种方便爆破现场测试振动效应的无线测试系统方案.每个测试节点采用3通道并行数据采集得到3个方向的振速值,采用通用GPS接收器的lpps脉冲来实现多节点的数据同步采集;控制器采用低功耗的FPGA;无线通信由nRF24LE1和nRF24LU1+来实现.该系统通过USB连入PC机,并利用VC++编写软件来实时显示和分析波...     

土壤湿度同化数据综合分析处理系统的研制与开发

陆面数据同化系统的输入和输出数据以其格式多样性、海量性为主要特征。以GIS二次开发组件ArcGIS Engine,ArcSDE空间数据库引擎和SQL Server 2005数据库管理工具,利用C#、IDL编程语言,构建土壤湿度同化数据空间数据库,并将气象数据具有时间域、空间域和属性域等多维属性与GIS数据模型相结合,研制开发综合分析处理系统,实现土壤湿度同化输入参数与输出数据的空间分析与管理。系统能够满足陆面同化系统对数据的处理与分析需求,为土壤湿度同化产品的业务应用提供强大的支撑。     

基于MSP430的低功耗煤气表系统设计

以煤气表充值为研究对象,设计了一套基于红外遥控的低功耗充值系统。该系统以MSP430G2553超低功耗单片机为核心,从硬件和软件两个方面设计了降低功耗方法,主要完成了安全充值、数据显示,以及煤气表的流量测量、剩余价格的显示、余量的显示和漏气等报警功能。实验结果验证了系统设计的合理性。该系统功耗低、操作方便、计量准确,同时可根据用户需要增加支持中文短信的GSM模块,能够及时、方便地进行远距离报警,提高煤气的安全使用。     

乐山旅游景区信息化解决方案

基于zigBee网络构建了一种智能旅游系统,通过该方法构建的智能网络系统能够方便地与外部设备进行连接,并提供SMT~DIP接口,同时可直接连接TTL接口设备,从而实现数据透明传输功能。该系统采用低功耗设计,最低功耗小于1mA,能应用于旅游景区的安全管理、客流量控制、票务管理和智能导游系统中。     

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.