基于6LoWPAN的智能家居环境监测系统设计

本文研究设计基于Pv6/6LoWPAN标准的居家环境监控系统。以6LoWIPAN边界路由器为核心,通过环境传感器检测环境中的温湿度以及空气质量,将数据上传到边界路由器,数据处理后边界路由器将数据经由Pv6网络传送到手机或PC机等客户端I,超过阈值时客户端通过边界路由器对电器下达开/关指令,达到室内温湿度及空气质量智能调节的目的,成功实现了6LoWPAN无线传感网与Pv6网络的对接。     

基于6LoWPAN的煤层瓦斯压力监测系统设计

针对目前煤层瓦斯压力监测存在测量精度低、数据传输不及时、设备部署不便等问题,设计了一种基于6LoWPAN的煤层瓦斯压力监测系统。该系统测压节点通过多跳方式在6LoWPAN网络中选择最优路径,将实时采集的瓦斯压力数据传输至边界路由器,边界路由器通过工业以太网将数据传至地面服务器,同时地面设备可通过服务器查询指定区域测压节点的实时监测数据。测试结果表明,该系统可实时、准确地监测煤层瓦斯压力,具有较高的数据通信效率和稳定性,且功耗低。     

基于6LoWPAN的边缘路由器设计研究

提出了一种智能6LoWPAN传感网络边缘路由器设计实现方法。该方法基于嵌入式操作系统Linux系统平台和单CPU的方案实现,通过在系统Linux上移植6LoWPAN协议簇,使射频接口LAN承载6LoWPAN网络,本地6LoWPAN传感网络通过边缘路由器接入互联网。6LoWPAN传感网络边缘路由器采用多协议融合的方式实现IPv4/IPv6双栈协议、NAT64协议、6to4隧道协议的统一,实现6LoWPAN网络节点通过6LoWPAN边缘路由器与互联网在不同网络环境下的自适应接入。     

基于6LoWPAN的嵌入式多网关系统设计与实现

6LoWPAN是一种在IEEE802.15.4标准基础上IP化实现无线传感器网络的技术。在现有单目的导向的有向无环图（DODAG）环路由协议标准下,存在围绕单边界路由器的网络拥塞和能耗问题。设计了一种嵌入式6LoWPAN多网关协议和系统,嵌入式网关节点具备双模通信功能,可实现无线传感网（WSN）和固定IPv6网络的物理连接,双模网关通过固网建立与6LoWPAN根边界路由器之间的IP隧道来实现上下行路由。通过对现有6LoWPAN协议标准的补充和优化,使双模节点具有网内和网际路由能力,从而实现多网关架构和多径路由功能。优化的多点互通拓扑位置和流量分担算法实现上下行链路的有效负载平衡,也减小了节点多跳路由能耗。通过对多网关平台进行实验测试,并与单网关系统对比测试,结果表明该方案不仅实现了6LoWPAN在以太网的多点接入,降低了网络内数据传输时延和丢包率,并且提升了网络整体吞吐量。     

基于NAT64的6LoWPAN边缘路由器设计

针对目前基于6LoWPAN边缘路由器只适用与IPv6设备互联、网络报文传输复杂繁琐、边缘路由器映射表复杂且开销大等问题,引入IEEE 802.15.4地址概念对6LoWPAN网络内报文交互方式与数据包格式进行优化,提出一种6LoWPAN与IPv4协议转换机制和边缘路由器地址映射转换方法,设计出适合在8位单片机上运行的轻量级微系统,最后用CoAP协议来访问节点数据,验证系统,实现6LoWPAN网络与IPv4,IPv6网络之间的通信.该方法实现了6LoWPAN与IPv4网络互联通信,保留6LoWAPN与IPv6网络通信的功能,同时提高了6LoWPAN内网络的吞吐量,降低边缘路由器维护地址映射表的开销,提高了边缘路由器效率,有效降低6LoWPAN网络传输数据时的功耗,提高节点生存时间.     

基于OpenWrt的6LoWPAN边界路由器的实现

OpenWrt作为一个高度模块化、自动化的嵌入式Linux系统,拥有强大的网络组建和扩展性。基于该系统,提出了一种6LoWPAN边界路由器的设计方案。通过在边界路由器上分别搭建两种协议栈,实现对于IPv6和6LoWPAN网络的接入;之后在协议栈之间建立SLIP通道,实现两种异构网络之间的通信。借助OpenWrt系统强大的路由功能和包管理机制,该边界路由器可以直接接入IPv6网络,并具备极强的拓展性。     

6LoWPAN无线心电传感网络架构与RPL优化仿真

阐述了通过心电采集节点、6LoWPAN边界路由器构建无线传感网络,实现了无线传感器网络(WSN)与IPV6网络之间的通信;针对RPI网络协议中的Trickle算法机制导致选择次优链路,影响网络路由的可靠性和稳定性问题,提出了优化方案;开展了仿真测试和优化后的网络性能指标分析;测试结果和分析表明,6LoWPAN无线传感网络不仅可以完成WSN与外部IPv6网络之间的连接承载数据收发,并且在对Trickle算法优化之后,对提高网络性能有较高影响.     

基于6LoWPAN的光伏汇流箱监测系统设计

针对传统汇流箱监测系统布线复杂、可扩展性差和成本高等缺点,以TI公司的CC2530作为硬件核心平台,设计了一套基于6LoWPAN无线传感网络技术的光伏汇流箱监测系统,通过C#.NET和SQL Sever2008开发了上位机监测平台。该汇流箱监测系统具有免布线、低成本和人机交互流畅等优点。搭建了一个包含5个监测节点、1个边界网关和一台PC服务器的测试网络。实验结果表明,该6LoWPAN监测系统实现了对汇流箱电能参数的实时监测和管理,其可靠性和稳定性能够满足光伏汇流箱监测系统的要求,具有较高应用价值。     

基于使用IPv6的低功耗无线个人局域网的无线传感网在智慧路灯中的应用

针对现有的采用电力载波通信(PLC)技术的智慧路灯系统中存在系统结构复杂、兼容性与扩展性差、开发部署周期长和安全性与抗干扰性低的问题,提出了一种基于IPv6的低功耗无线个人局域网(6LoWPAN)的智慧路灯系统。将6LoWPAN应用在对基于PLC的智慧路灯系统的改造中,把原有的PLC节点改成6LoWPAN无线节点,把集中控制器改造为边界路由器,并在应用层上采用了受限应用协议(CoAP)和智能物体网际协议(IPSO)应用框架。通过与基于PLC的智慧路灯进行对比,结果表明采用6LoWPAN无线网络的智慧路灯系统结构简化、兼容性与扩展性高、系统开发部署周期缩短一半以上并且网络安全性和抗干扰性较高。     

一种基于6LoWPAN的TCP报头压缩方案

TCP是一种可靠的传输层协议, 许多应用有强烈的可靠性要求, 需要TCP的支持. 6LoWPAN网络受节点硬件资源与底层通信协议限制, 需要对TCP报头进行压缩, 然而目前尚无相关标准.在研究现有TCP报头压缩方案的基础上, 针对6LoWPAN网络的特点, 提出了一种适用于6LoWPAN网络的TCP报头压缩方案LOWPAN_TCP_HC, 并进行了测试. 实验结果表明LOWPAN_TCP_HC能够有效压缩TCP报头, 减少传感器节点能量消耗, 延长节点使用时间.     

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.