无线传感器网络中能量有效的加权分簇算法

针对无线传感器网络中节点受到能量和带宽等资源严格制约的问题,通过分簇可以使网络中节点能量负载均衡,从而延长网络的生存周期.从能量和节点度的角度出发,分析了无线传感器网络中现有的一些分簇算法提出,了一种新的适合于无线传感器网络的能量有效的加权分簇算法,通过仿真和分析得出,该算法是一种有效的分簇算法.     

一种抗干扰半静态分簇路由算法

针对无线传感器网络( WSNs)分簇路由算法中的能量洞、热点和抗干扰问题,设计一种抗干扰半静态分簇( AlSSC)路由算法,给无线传感器网络提供能量多、距离短、链路质量好的路径来传输数据.该算法利用节点定位获取节点地理位置,综合考虑传感器节点剩余能量和干扰信噪比,通过节点距离度量、节点聚簇、簇间融合、簇头选举和簇头轮换五个步骤进行无线传感器网络节点的分簇.仿真结果表明:这种路由算法可以提高无线传感器网络通信链路质量,均衡网络能量消耗.     

一种基于能量均衡的无线传感器网络协议

无线传感器网络协议LEACH中提到了分簇的思想,能够有效的减少节点在通信中的能量消耗,延长网络的生存时间.为了更有效的减少节点的能量消耗,延长网络的生存时间,可以在分簇的算法中采用能量均衡的思想,同时簇头收集数据后通过一棵路由树向汇聚节点发送数据.实验表明采用基于能量均衡的分簇算法的无线传感器有更好的整体性能和网络生存时间.     

无线传感器网络中一种层次分簇算法及协作性分析

无线传感器网络是传感技术、计算技术和通信技术的融合.由于传感器节点的能量限制,能量有效性是设计无线传感器网络所关注的一个主要内容,并且已成为一个最大的挑战.提出了一种网络拓扑算法--一种动态、能量有效的层次分簇算法(DEEH).与其他算法不同,该算法无须知道传感器节点的任何本地信息.该算法可应用于更实际的大规模无线传感器网络,如节点具有不同的能量等级、不同的传输半径.将DEEH算法与经典的分簇算法LEACH相比较,仿真结果表明:当网络节点密度很大时,DEEH优于LEACH.同时,还考虑了网络中存在自私节点的情况,并分析了自私节点对网络分簇所带来的影响.在DEEH算法中引入机制设计理论,以克服网络中自私节点的影响.实验结果表明:采用机制设计理论,自私节点的占优策略真实地报告它们的能量.这一策略延长了网络的寿命,保证了拓扑结构的稳定性.     

无线传感器网络分簇算法的仿真研究

针对无线传感器网络分簇中节点负载不均衡的间题,提出了一种基于免疫记忆粒子群优化算法的分簇算法.算法对能力异构环境下的无线传感器网络的适应性和扩展性较好,且节能高效,实现简单.该算法在每轮运算过程中,利用节点负载能力预评估因子和节点能量预评估因子对无线传感器网络进行区域分割,获得能量均衡及负载能力均衡的分区,并在分区中通过免疫记忆粒子群算法选取簇头,使簇头具有高能量、负载能力强的优点.仿真结果表明,算法不仅在能量有效性、负载均衡性方面有良好的效果,而且延长网络生命周期和缩短建簇时间.因此,该算法在解决无线传感器网络节点不均衡问题上具有一定的实用性.     

WSN免疫模型设计及其分簇算法

针对无线传感器网络容易出现能量衰竭和分簇繁琐问题,设计一种基于人工免疫计算理论的无线传感器网络模型,采用网格理论来划分初始簇,并对网络节点及节点簇等进行相关定义。最后提出一种免疫型无线传感器网络分簇算法——aiCWSN。通过实验,该模型和算法能够减少网络能量过快衰竭和提高网络的收敛性。     

基于分簇的无线传感器网络节能路由算法

无线传感器网络中,节点能量及其消耗率影响网络的稳定性和整个网络的生命周期.针对传感器网络能量有限的特点,提出了一种基于分簇的节能路由算法.通过用改进的四色算法选举簇头,并建立网络逻辑簇结构,使网络簇的逻辑结构更加合理.以节能为目的,增加了能量信息维护和节点能量保护.仿真实验表明了该算法的有效性.     

一种综合能量和节点度的传感器网络分簇算法

针对无线传感器网络分簇过程中簇首耗能过快问题,提出了一种综合节点剩余能量和节点度数进行簇首选取的分簇算法ENCA(energy and node degree synthesized clustering algorithm).该算法在每轮的簇首选取中考虑了每个簇内所有节点的剩余能量和平均剩余能量,并在每个簇中依据节点的度数优化簇首的选择.在算法运行过程中,在保证网络连通的同时,避免了能量较低的节点当选为簇首.仿真结果表明,与LEACH算法和ACE算法相比,ENCA算法均衡了网络中节点的能量消耗,有效延长了网络寿命.     

蚁群优化的无线传感器网络分簇方法研究

分簇算法是无线传感器网络中减少网络能量消耗的一种重要方法。为了有效使用无线传感器节点有限的能量,将蚁群优化算法应用于无线传感器网络的路径选择,利用蚁群的动态适应性和寻优能力,在分簇产生的簇头节点之间找到最优路径,进而达到均衡网络负载、延长整个网络寿命的目的。模拟仿真实验结果表明了该算法的可行性和有效性。     

一种无线传感器网络分簇规模约束算法

针对无线传感器网络节点能耗受限和不同节点能量开销不平衡的问题,对于分层结构的无线传感器网络提出了一种分簇规模约束算法.该算法是通过对簇内节点数量设置上下限的方式,对簇规模大小进行限制.如果簇中节点的数量超过上限(U),该簇就被划分为两个簇;如果簇中节点的数量低于下限(L),该簇就会和邻居簇相结合.在自组簇的形成过程中采用该算法,可减少节点能量开销和增加簇的稳定性.     

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.     

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