基于CC2530的环境监测系统的设计与实现

针对传统环境监测系统布线复杂、功耗高、设备维护不便等问题,设计一个以CC2530芯片为核心的ZigBee无线环境监测系统;该系统以CC2530为主控芯片,基于ZigBee协议栈构建无线网络实现协调器节点和现场终端节点之间数据的收发,利用串口通信技术实现协调器节点和PC机之间的通信;从系统的整体设计方案、系统的硬件设计、系统的软件设计和系统的性能测试4个方面对系统进行简单介绍;经实验证明,该系统性能稳定、实时性强、功耗低、可扩展性强,可广泛应用于对环境参数要求比较高的场合。     

基于CC2530的ZigBee协调器节点设计

为了使无线传感器网络节点获得更好的通信效果,给出了采用TI公司的CC2530作为主芯片对ZigBee网络中的协调器节点进行设计的方法。该方法选用TI公司的CC2591作为射频前端芯片,并给出了硬件设计中各功能模块的连接方式,同时对协调器组建网络及子节点通过关联协调器节点接入网络进行了分析。实际测试结果表明,该设计的节点通信距离较远且接收灵敏度高,能适用于智能家居等多种场合。     

基于无线传感器网络的智能生态保障系统

为满足多功能、多给水条件,研究设计了一种基于无线传感器网络的智能生态保障系统。以CC2530芯片为基础设计了传感器节点和给水控制节点;以低功耗MSP430芯片结合CC2530设计了主控节点。系统可以根据预设的植物种类、时间信息确定植物的生长周期,并依据感知的环境参数,针对植物的不同生长周期生成灌溉策略来实现自动灌溉。测试结果表明,系统提供了对自来水、无压蓄水等不同给水条件的适应能力,克服了现有系统功能单一、使用范围小、灌溉控制不合理的缺点。     

列车安全距离控制形式化建模与验证

随着我国铁路的迅速发展,对列车运行安全性的要求越来越高。采用Event-B形式化建模方法研究了高速列车安全距离控制形式化验证问题,以Event-B形式化仿真工具Rodin为基础,通过结合多智能体理论,引入感知决策法则,实现了无线闭塞中心(RBC)与列车的车地通信,建立了多列车运行的安全距离控制模型。仿真研究了高速列车最小间隔追踪控制运行,对列车安全距离控车行为进行了形式化建模并进行了POs证明义务验证。仿真结果表明,对于CTCS列车控制系统的复杂逻辑关联行为,采用提出的Event-B和多智能体系统(MAS)结合的形式化验证方法,可进行系统规范的模型验证,对于复杂系统的逻辑验证有较强的实际意义。     

列车安全距离控制形式化建模与验证

随着我国铁路的迅速发展,对列车运行安全性的要求越来越高。采用Event-B形式化建模方法研究了高速列车安全距离控制形式化验证问题,以Event-B形式化仿真工具Rodin为基础,通过结合多智能体理论,引入感知决策法则,实现了无线闭塞中心(RBC)与列车的车地通信,建立了多列车运行的安全距离控制模型。仿真研究了高速列车最小间隔追踪控制运行,对列车安全距离控车行为进行了形式化建模并进行了POs证明义务验证。仿真结果表明,对于CTCS列车控制系统的复杂逻辑关联行为,采用提出的Event-B和多智能体系统(MAS)结合的形式化验证方法,可进行系统规范的模型验证,对于复杂系统的逻辑验证有较强的实际意义。     

基于MSP430和CC2530的空调远程控制节点的设计

给出了智能家居空调远程控制系统的总体设计方案,完成了以低功耗芯片MSP430和CC2530为基础的控制节点设计,实现了对室内空调的远程控制和温湿度数据的采集,制定了MSP430与CC2530之间的通信协议.系统测试结果表明该智能家居系统运行可靠,实时性高,能够对室内空调进行远程控制和现场控制,具有良好的应用前景.     

一种低功耗的无线传感器网络节点设计方法

提出一种低功耗的无线传感器网络节点设计方法,采用CC2530芯片,基于ZigBee技术实现无线传感器网络的自组和监测数据的自动汇聚。给出节点设计的整体框图以及硬件设计模块与软件设计流程。以温度采集系统为对象进行实验,结果证明,以该方法设计的节点具有低功耗、高精度的特点。     

基于Android的智能家居交互系统设计与开发

该系统采用ZigBee芯片CC2530和WiFi芯片ESP8266作为主要构件搭建智能网关。利用串口UART在CC2530和ESP8266间进行数据传输，实现ZigBee-WiFi网络的转换。使用CC2530芯片搭建终端电路实现设备状态信息的获取并通过ZigBee网络与智能网关互联实现物联网的构建。在基于Android系统的智能手机开发APP，以实现智能家居工作状态的获取及控制指令的发送。设计基于Android客户端的WEB服务器，以实现外部网络对智能家居的控制。     

CC2530和FPGA的新型无线网络节点设计

采用ZigBee协议组成无线网络,设计出可以自动接入该无线网络的节点,使用了基于ZigBee技术的CC2530芯片和FP-GA。摒弃了以往采用MCU控制CC2530的方式,对本身具有8051内核的CC2530芯片进行更大限度地利用。详细地论述了一种新型无线网络节点的设计方法,实现了可靠和高速的无线网络数据传输,具有操作方便快捷、低功耗和便于移动的优点。     

基于ZigBee的门式起重机安全监控管理系统

根据门式起重机运行状态安全监控需要,结合ZigBee无线通信技术,设计开发了一种应用于门式起重机的安全监控管理系统.该系统网络节点硬件以STC12C5A60S2为控制器、CC2530为射频收发器.阐述了网络的节点硬件和软件设计,并介绍了上位机监控系统.经实际调试验证,该监控系统具有信号采集与处理准确、控制输出实时、人机交互友好等特点,实现了门式起重机运行的安全监控.     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.