无线传感器网络中的最大生命期基因路由算法

无线传感器网络(wireless sensor networks,简称WSNs)由一组低功率且能量受限的传感器节点构成,设计此类网络的一个基本挑战便是最大化网络生命期的问题.在WSNs中,由于邻近传感器节点所收集的数据之间往往具有时空相关性,多采用数据聚合技术作为去除数据冗余、压缩数据大小的有效手段.合理地应用数据聚合技术,可以有效地减少数据传递量,降低网络能耗,从而延长网络生命期.研究了WSNs中结合数据聚合与节点功率控制的优化数据传递技术,提出了一种新的最大化网络生命期的路由算法.该算法采用遗传算法(genetic algorithm,简称GA)最优化数据聚合点的选择,并采用梯度算法进一步优化结果.该算法均衡节点能耗,并最大化网络生命期.仿真结果表明,该算法极大地提高了网络的生命期.     

无线传感器网络中的最大生命期基因路由算法

无线传感器网络(wireless sensor networks,简称WSNs)由一组低功率且能量受限的传感器节点构成,设计此类网络的一个基本挑战便是最大化网络生命期的问题.在WSNs中,由于邻近传感器节点所收集的数据之间往往具有时空相关性,多采用数据聚合技术作为去除数据冗余、压缩数据大小的有效手段.合理地应用数据聚合技术,可以有效地减少数据传递量,降低网络能耗,从而延长网络生命期.研究了WSNs中结合数据聚合与节点功率控制的优化数据传递技术,提出了一种新的最大化网络生命期的路由算法.该算法采用遗传算法(genetic algorithm,简称GA)最优化数据聚合点的选择,并采用梯度算法进一步优化结果.该算法均衡节点能耗,并最大化网络生命期.仿真结果表明,该算法极大地提高了网络的生命期.     

基于蚁群算法的WSNs节点有障环境中部署优化研究

能量限制是无线传感器网络(WSNs)技术中一个关键问题.提出了一种通过无线信道能耗衰减模型利用Dijkstra算法和蚁群算法相结合的WSNs节点静态优化部署策略.通过该策略对两种不同的环境仿真部署验证表明:该策略能更好地优化节点在复杂二维地理环境中的静态部署,并可有效地减少网络的能耗,提高WSNs的使用寿命.     

基于非合作博弈的无线传感器网络功率控制研究

如何提高能量的有效性是无线传感器网络（WSNs）设计的重要问题,针对WSNs在多媒体等业务中的应用,对基于码分多址（CDMA）通信方式的WSNs模型,提出一种基于非合作博弈的WSNs功率控制算法,并证明了该算法纳什均衡的存在性及唯一性.仿真结果表明,所提出的算法在设计时充分考虑了节点的剩余能量问题,因此能够很好地降低网络的总发射功率,有效地节约节点能量,延长网络的生命周期.     

一种基于苯环结构的WSNs故障检测算法

节点故障是无线传感器网络(WSNs)研究中的一个重要问题。由于WSNs规模大,节点能量受限,加之传感器制作工艺等方面的原因,使得节点发生故障的概率较高。针对WSNs中的节点故障问题,提出一种基于苯环结构的节点故障检测算法。该算法利用苯环结构的对称性,减少邻居节点的数目从而达到降低故障检测能耗的目的,同时延长了网络的生存周期。采用OMNeT++建立仿真环境,对算法性能进行测试。测试结果表明:该算法较其他算法具有较低的能量消耗和较高的网络连通性及可扩展性。     

基于协作传输的大范围WSNs能耗均衡分簇算法

由于大范围无线传感器网络（WSNs）节点的数量巨大,网络的能量消耗极不均,提出一种基于协作传输的分簇算法—EBBMCC—LS算法。该算法在保证网络均匀分簇的前提下,能保证网络中簇头节点的均匀分布,在簇间通信时加入协作传输策略,传感器节点之间通过协作传输构成虚拟多天线系统,改善系统性能,解决了大范围WSNs中的能耗不均现象。实验验证：该算法能够均衡大范围WSNs中的能耗,延长网络寿命,可促进大范围WSNs应用的推广。     

WSN中基于博弈论的节点功率控制算法

针对如何降低无线传感器网络中节点传输的能量消耗,延长网络生存周期,本文将博弈论引入WSN功率控制中,综合考虑节点的剩余能量、发射功率等因素构建效用函数,将剩余能量较大的节点作为下一跳节点,连接其他节点并承载较多的传输任务.节点在通信过程中以功率博弈算法作为策略方案,不断调整各自的策略,提高信息传输的准确率,并证明该算法纳什均衡的存在.仿真结果表明,与传统分布式功率控制算法相比,该算法通过控制节点传输功率实现了降低能耗的目的,能更快迭代出最优发射功率,并得到较大的信干比.     

基于工作周期优化的能量采集节点的功率控制

在无线传感网络WSNs(Wireless Sensor Networks)中,节点受到能量限制,因此,需通过功率管理技术有效地使用电池.而能量采集是补给电池能量的有效方式.为此,针对能量采集节点,提出功率控制算法,记为CLPM-PTPC(Close-Loop Power Manager-Predictive Transmission Power Controller).CLPM-PTPC算法是通过联合工作周期的优化和传输功率控制,实现节点功率的管理.CLPM-PTPC算法先利用闭环功率管理CLPM(Close-Loop Power Manager)调整传输任务的工作时期,再依据功率控制器PTPC(Predictive Transmission Power Controller)调整发射功率,使得传输功率能够实时地依据无线信道环境调整.实验数据表明,与基于固定传输功率算法相比,CLPM-PTPC算法的能量效率提高了约15％.     

一种无线传感器网络能耗均衡的自适应拓扑博弈算法

针对无线传感器网络节点能量有限与能耗不均衡导致网络生命周期提前结束的问题,运用势博弈理论将节点的平均寿命、节点最短寿命、网络的连通性以及覆盖性应用到效益函数的设计中,建立一种基于序数势博弈的能耗均衡的拓扑控制模型,以证明博弈模型是序数势博弈.基于该势博弈模型,提出一种能耗均衡的自适应拓扑博弈算法.该算法根据节点平均寿命调整自身的功率,帮助最短寿命节点降低功率,延长整个网络的生存时间.仿真实验及对比分析表明,所提出的算法相比于其他基于博弈论的拓扑控制算法,能够改善网络能量的均衡性,提高网络能量效率,保证网络拓扑的健壮性,增强网络拓扑的自适应性.     

基于质心理论的多Sink节点重选址算法

针对无线传感器网络WSNs(Wireless Sensor Networks)中Sink节点静止不动附近邻居节点易出现"能量空洞"、缩短网络生命周期等问题,提出一种基于质心的多Sink节点重选址算法.将网络中某段时间内向Sink节点发送过数据包的全部一跳邻居节点视为质点系,所发送的数据量作为质点质量,使Sink节点向着传感器节点密度大的方向移动,实现多个Sink节点相互协作,逐步逼近到该质点系的质心位置.将质心重选址算法与多Sink节点位置固定的重选址算法和COST函数多Sink节点重选址算法进行仿真对比,结果表明质心重选址算法可以有效的均衡网络负载,降低网络能耗,延长网络生命周期,提高网络性能.     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。