基于分簇的无线传感器网络路由协议的分析与优化

无线传感器网络（WSN）中的传感器节点由于受到成本、体积等因素的限制,处理能力、无线带宽,以及电池容量等资源都非常有限。由于WSN是一种资源受限网络,尤其是能量的受限,因此路由协议必须维持较小的路由信息并尽可能的减少能耗。基于分簇的层次路由协议是目前解决此类问题的主要方法。在对传感器网络路由协议作了充分了解的基础上深入研究了经典的簇类路由算法一LEACH（Low Energy Adaptive Clustering Hierarchy）,并针对其不足对其进行改进与优化。     

基于簇首能量均衡分布的无线传感器网络LEACH协议改进

能量有限性是无线传感器网络(WSN)的最重要的特性,在网络路由算法中也是优先考虑的一个主要因素。分析了传统LEACH算法的不足,并对一些改进协议的LEACH进行认真研究,在此基础上提出了一种新的LEACH改进协议,仿真结果表明,改进后的协议能均衡节点能耗,提高了负载均衡度,并延长了无线传感器网络的生存时间。     

基于改进ACO的WSN感知数据传输策略研究

无线传感器网络(WSN)能够利用传感器节点快速准确地获取物理世界的信息从而作为物联网的感知层在监控领域得到了广泛的应用,而能量利用率是能量受限无线传感器网络的一个关键属性,直接影响网络的生命周期.经典的分层路由LEACH(及其变种)算法是无线传感器网络中最常见的节能路由协议.该文提出了一种改进的LEACH算法,由sin...     

一种基于LEAC日协议的分簇路由算法

低能自适应聚类路由协议(LEACH协议)是为无线传感器网络设计的一种低功耗自适应分层路由协议,具有延长网络生命时间的作用.为了均衡无线传感器网络节点的能耗,延长整个网络的生命周期,通过对LEACH协议的研究,对簇首的选取和簇首与Sink的通信机制进行优化,提出了一种改进的LEACH协议的分簇路由算法.通过Madab仿真实验证明,改进后的LEACH算法在网络生命周期和网络能量消耗等方面比LEACH算法有较大的提高.     

基于能量优化的无线传感器网络分簇路由算法研究

无线传感器网络的路由协议设计要同时关注单个节点的能耗及整个网络能量的均衡消耗.分簇算法能有效解决节点能耗受限与不同节点能量开销不平衡问题.在分析了传统分簇路由LEACH(low energy adaptive clustering hierarchy)协议中选择簇头算法不足和当前一些典型基于LEACH思想的路由改进算法...     

无线传感器网络备份路径分簇算法

在路由协议中利用分簇技术可以提高无线传感器网络的可扩展性。针对无线传感器网络(WSN)中分簇算法的不足,提出了基于备份节点策略的EDC算法,传感器节点在其簇头失效后仍可以通过其备份路径传输数据。通过OMNeT++平台上的仿真实验表明,EDC在网络重建时间、失效节点数量较其他WSN协议有明显的改善。     

基于能量度量的无线传感器网络跨层协议的研究

无线传感器网络(WSN)是近年发展起来的一项新技术,但由于它是电池供能,节能成为无线传感器网络的重要研究课题之一。文章在阐述传统的分层协议栈弊端的基础上,提出了一种融合MAC层和路由层的跨层协议设计方案。仿真结果表明,文章所提出的算法能显著减少网络能耗,提高能源有效性。     

基于多态蚁群算法的WSN能耗均衡路由协议

针对无线传感器网络(WSN)的能耗均衡问题,提出一种基于多态蚁群算法的路由协议,采用周期传输和数据融合的方式,将无线传感器节点的剩余能量信息融合到信息素的形成中。仿真实验表明,与Leach协议相比,采用该协议有82%的节点生命周期更长,在相同时间内网络可多传输48%的数据包。在实验室使用31个节点部署无线传感器网络,将路由协议应用于网络。实验结果验证了该协议的有效性。     

无线传感器网络分簇路由协议的改进研究

针对无线传感器网络(WSN)中分簇路由协议LEACH算法中簇首分配不均以及簇首与Sink节点直接通信问题进行研究,提出一种基于LEACH成簇思想的分簇路由协议。该算法基于节点剩余能耗和已担任簇首时间选举簇头。簇头间采用贪婪算法形成一条链,在该链中又选出一个簇头,将整个网络的数据融合后转发给基站。MatLab仿真结果显示,改进后的算法在均衡网络节点能耗和网络的生存时间上比LEACH算法有很大提高。     

基于小世界的无线传感器网络的路由算法

针对小世界的拓扑特性,提出一种基于小世界的无线传感器网络(WSN)的路由算法。该路由算法引入超级节点环概念,将超级节点环视为无向图,利用改进的Floyd算法计算出最短传输路径,缩短路由建立时间,进而提高网络的传输效率,降低无线传感器网络的能耗。仿真结果表明,该算法与针对小世界提出的路由算法PSCF、SWRP和MH相比,在路由建立时间、能量消耗和网络吞吐量方面效果显著。     

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.     

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.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate