基于链路质量的无线传感器网络任播路由协议

无线传感器网络(WSN)中,由于无线链路的链路质量问题,经常有传递失败导致重传耗费能量的现象出现。传统任播路由协议只以路由距离作为路由判据,而没有讨论链路质量问题,将其应用在WSN中会造成路由权重设置不合理。提出了基于链路质量的WSN任播路由协议,该协议在讨论链路质量的计算之上,以能耗均衡和系统能耗最小这两个因素决定任播路径的路由权重,并以参数α来权衡两者之间的关系。实验证明,在WSN中,相比传统任播路由协议,该协议能更有效地均衡能耗,减少系统能耗,从而优化网络生存期。     

基于进化算法的无线传感器网络任播路由算法

在无线传感器网络WSN(Wireless Sensor Networks)中存在无线链路容易失效的现象,但大多数学者在设计路由算法时较多地关注网络生存期问题,而忽略路由健壮性问题.提出一种基于进化算法的WSN任播路由算法.该算法以网络生存期和路由健壮性为优化目标,并通过多目标进化算法寻找到两者的最佳适应值.实验验证了该算法的有效性,实验数据表明:相比较基于单目标优化(网络生存期)的任播路由算法,所提算法的网络生存期及路由健壮性两个性能的综合优化值优于前者;相比较传统单路径任播路由算法,所提算法的网络生存期、路由健壮性和可扩展性优于前者.     

能量均衡的WSN非均匀分簇路由算法

针对现有无线传感器网络（WSN）分层分簇路由算法存在的能耗不均衡问题,提出一种能耗均衡的WSN非均匀分簇路由算法。该算法通过在已划分的非均匀区域中构建中间层达到均衡簇首和其他节点能耗的目的,实现WSN整体能耗均衡。实验结果表明,该算法能均衡WSN能耗负载,提高WSN的能量效率,延长100轮～200轮WSN生命周期。     

基于时延敏感无线传感器网络的最优任播算法

任播技术应用在基于休眠唤醒机制的无线传感器网络(WSN)中可以改善其时延较长的问题,但以往技术是针对每一跳候选节点的休眠时延进行优化的,该策略在端对端时延上往往并不最优甚至有时效果很差。针对端对端时延问题提出基于时延敏感WSN的最优任播算法。协议中基站采用AODV多路径路由协议获取任播路径信息,采用遗传算法进行最优化计算,并将所得各节点至任播组最优任播路径的信息返回给各节点。该算法具有自适应调节任播路径和全局优化的特点。实验数据表明,与以往算法相比,该算法可以更有效地降低端对端时延。     

具备网络编码感知的能耗友好WSN路由策略

为均衡及降低无线传感器网络(WSN)的路由能耗并最终延长网络的寿命,提出一种具备网络编码感知且能耗敏感的WSN路由策略。该策略通过对WSN环境中存在的网络寿命限制、数据流限制、广播流量限制3个重要因素的分析,对能耗最优路由进行建模,最后归结为对最优化问题的求解获得最佳路径。仿真实验表明该路由策略能够较好地均衡节点的能耗,从整体上显著延长WSN的生存期。     

一种能量有效的WSN分簇路由算法

针对无线传感器网络(WSN)中的热区问题,提出一种能量有效的WSN分簇路由算法EERA。以基站为圆心将整个感知区域划分为大小不等的圆环,依据节点剩余能量和相对位置选择簇首。簇间采用多跳路由传输数据,路由构建时考虑节点接收和发送数据能耗,将发送距离限制在阈值之内且尽量减少中转次数,簇首节点在稳定传输阶段动态改变转发路径。仿真结果表明,EERA能有效降低网络能耗,均衡网络节点的能耗,延长网络生命周期。     

可充电无线传感网络能量均衡路由算法

针对可充电无线传感网络中的能量均衡路由问题,提出在稳定功率无线充电和监测数据收集网络场景下的多路径路由算法和机会路由算法,以实现网络的能量均衡。首先,通过电磁传播理论构建了无线传感节点的充电和接收功率关系模型;然后,考虑网络中无线传感节点的发送能耗和接收能耗,基于上述充电模型将网络能量均衡的路由问题转化为网络节点运行时间的最大最小化问题,通过线性规划得到的各链路流量用以指导路由中数据流量分配;最后,考虑一种更加现实的低功耗的场景,并提出了一种基于机会路由的能量均衡路由算法。实验结果表明,与最短路径路由（SPR）和期望周期最短路由（EDC）算法相比较,所提出的两种路由算法均能有效提高采集能量的利用率和工作周期内的网络生命周期。     

低冗余度WSN非均匀分簇算法应用研究

将传统非均匀分簇算法应用于低冗余度的无线传感器网络(WSN)中时,存在传感器节点早衰和簇间多跳通信传输能量开销不均衡的问题。为此,针对低冗余度WSN,提出基于粒子群和最短路由树的非均匀分簇路由算法。利用粒子群算法优化非均匀分簇过程,通过建立最短路由树搜索簇间多跳传输最优路径,实现数据从传感器节点到基站的高效传输。仿真结果表明,相比于EECS和EEUC算法,该算法可有效延长低冗余度WSN的网络生命时间,均衡簇间通信能量消耗。     

一种聚类区域自适应调整的WSN能耗均衡分簇算法

详细分析LEACH协议,针对LEACH协议随机产生簇头导致网络中出现局部区域簇头分布不均、簇的规模不一、整个网络能耗不均衡、网络寿命缩短等问题,提出了一种聚类区域自适应调整的WSN能耗均衡分簇算法。在算法的选举簇头阶段,将节点剩余能量、备选簇头与邻居簇头的间距相结合作为判据参数;在成簇阶段,将节点预加入的簇头到基站的距离考虑在内,比较多个数据流向,采用节能最优路径策略。仿真结果表明,该协议能够有效均衡网络各节点能耗,显著延长了网络生存时间。     

基于全局均衡策略的无线传感器网络路由算法

针对无线传感器网络的能耗均衡问题,提出了一种基于全局均衡策略的路由算法。该算法一方面利用基于区域划分的非均匀分簇方法均衡WSN数据收集汇聚树纵向上簇头之间的能耗;另一方面应用基于能耗与剩余能量复合权值的Dijkstra算法优化簇间路由——降低传输能耗并分摊数据转发任务,以均衡汇聚树横向上簇头之间的能耗。仿真实验结果表明,该路由算法能够有效地均衡网络中节点的能耗,显著延长网络的生存期。     

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。