无线传感器网络节点基于遗传算法的充电路径规划

无线传感器网络应用越来越广泛,为了解决传感器节点的能量问题,将无线充电技术应用到传感器网络中.使用无人机为传感器节点进行无线充电,但是无人机的电池容量有限,合理的规划能够让无人机以最小的充电代价获得最大的网络效用.以最小化无人机能耗为优化目标,对无人机能量消耗进行分析,将优化目标简化成最小化路径距离,并使用遗传算法对无...     

WRSN联合无线充电和数据收集的周期性充电规划

针对无线可充电传感器网络中无线充电设备(WCE)兼顾充电和数据收集的情况,提出了联合无线充电和数据收集的周期性充电规划问题,并证明了该问题是NP-complete问题.首先分析了无线充电和数据收集对WCE路径规划的影响,根据传感器节点当前的剩余能量和数据量计算出WCE需要停留的时间;然后证明了最优方案是在周期时间最大化的前提下获得的;最后设计出多种群离散烟花算法(MFWA)求解该问题.在MatlabR2016a中生成不同节点数目的网络场景进行仿真,结果表明, MFWA算法的性能优于DFWA算法.     

一种移动充电器对无线传感器节点充电的调度模型

无线传感器节点能量有限的问题始终是其稳定运行的瓶颈.为保证节点具有稳定的能量供应,本文利用无线充电的方式为节点补充能量.首先,采用线性规划的方法对无线充电车的调度问题作出定义,同时综合考虑节点充电过程中的时间和空间因素,使用改进的引力搜索算法按需规划节点被服务的顺序.根据对节点被服务顺序的规划,使用单辆无线充电车携带多个可分离充电装置在多位置上为节点并发服务.最后,对所提出的算法进行仿真.仿真结果表明,所提出的算法在充电延迟方面明显优于现有的FCFS算法、NJNP算法以及经典的引力搜索算法.     

一种基于非均匀分簇的实时充电算法

针对具有实时性要求的无线可充电传感器网络,使用移动充电器及时为网络中的节点补充能量,提出一种基于非均匀分簇的实时充电算法(nUCRC):首先采用非均匀分簇的方法,将网络划分为大小不等的多个簇,通过研究簇内节点的能量状态和充电截止时间决定簇头的选举和轮换;采用动态规划算法得出移动充电器的簇间最短移动路径,并根据簇内节点的时间和空间的混合优先级决定充电顺序,遍历完所有簇后,返回基站结束当前充电周期.仿真结果表明采用nUCRC算法比采用目前最新的按需充电算法的节点存活率提高约10％,平均充电时延提升约20％,更加适用于具有实时性要求的网络.     

QoS保障下的无人机传感网安全通信路径规划

在无线传感器网络中,无人机在传感器覆盖区域内定期巡游,以收集传感器感知的数据。由于无线信道的广播性质,信息更容易被地面上的非法节点窃听,无线通信安全受到挑战。通过无人机的轨迹规划和传感器功率控制可以在物理层保障无线通信的安全性。然而,现有研究无人机辅助无线通信路径规划的文献中,没有考虑到用户或节点需要最小通信时间来保证服务质量。针对此问题,在无线传感器网络通信系统中,加入最小通信时间约束,通过联合优化无人机的飞行轨迹、传感器的发送功率和无人机服务传感器的调度顺序,提出平均保密率最大化问题,并证明了其非凸性。为解决所提的非凸问题,将原问题分解为3个子问题,提出了一个应用块坐标下降、连续凸优化、迭代舍入方法的快速收敛迭代算法TPA。实验结果表明,所提算法TPA的平均保密率比未进行轨迹优化的基准算法提高了15.7%,比未进行功率控制的基准算法提高了159.8%。TPA与未加入最小通信时间约束的基准算法相比,在2种不同任务分布情况下,当无人机飞行周期大于70 s时,任务完成率平均提升44.6%和27.1%。     

面向无线传感器网络节点定位的移动锚节点路径规划

节点定位是无线传感器网络技术研究的一个基本问题,大多数无线传感器网络的应用和中间件技术都需要节点的位置信息.目前比较实用的定位方法是利用一些移动锚节点(如安装有GPS)根据有效的规划路径移动,通过发送包含其自身坐标的信息来定位其他节点,该方法不过多地增加无线传感器网络成本,还可以获得较高的定位精度.在该方法中,移动锚节点的路径规划问题是需要解决的基本问题.主要研究移动锚节点的路径规划问题,把图论引入到无线传感器网络节点定位系统.把无线传感器网络看成一个连通的节点无向图,路径规划问题转化为图的生成树及遍历问题,提出了宽度优先和回溯式贪婪算法.仿真实验和真实系统实验结果表明,该方法能够很好地适应无线传感器网络节点随机分布的节点定位,可以取得较高的定位精度.     

基于时空协作的多移动充电器充电路径规划的研究

为解决大型无线可充电传感器网络中节点的实时充电问题,对具有多个移动充电器的网络进行了研究。在将网络公平划分为多个簇的基础上提出一种基于时空协作的多移动充电器实时充电算法STMA：通过联合考虑节点的空间位置和截止充电时间要求规划移动充电器的充电路径,在充电过程中及时获取最新的充电请求,并按照充电请求的紧急程度及时调整充电路径。仿真结果表明,采用STMA算法比单纯考虑时空要求的算法的能量利用率提高约14%,节点存活率提高约9%,更加适应节点的实时充电需求。     

联合无线充电与数据收集的移动充电装置多目标路径规划算法

针对无线传感器网络节点资源有限导致数据收集不完整和时效性差的问题，建立了联合无线充电和数据收集的移动充电装置（MCD）多目标路径规划模型，提出了一种基于贪心策略的联合无线充电和数据收集的MCD路径规划算法(PPGS)。首先，对监测区域采用基于正六边形的无缝划分策略，有效减少了MCD的访问单元数；然后，利用马尔可夫模型预测节点能量和数据采集量等参数，在此基础上预估了MCD锚点最小停留时间和最长等待时间。与现有时延受限移动式能量补充算法(DCMEC)和基于网格的移动装置调度算法(GBA+MDSA)相比，所提算法具有复杂度较低，且无需事先知道节点和锚点实际位置信息的优势。仿真结果表明：PPGS能以较少的MCD保证无线传感器网络数据收集的完整性和时效性。     

多节点部分充电模型下的充电调度优化

在无线可充电传感器网络中,针对移动充电车采用多节点部分充电模型在充电调度过程中往复行驶,导致充电时间增加的问题进行了研究。提出一种新颖的多节点部分充电模型,从全局优化移动充电车在每个充电位置的充电时间,保证每个能量临界的传感器被充满电。同时提出AlgMinTime算法进行路径规划,确定移动充电车的充电环路以及对应位置的充电时间,使得环路上总充电调度时间最小化。最终通过仿真实验评估所提出算法的性能。实验结果表明,所提算法的充电调度平均环路时间相较于SOTA算法缩短9.8%。     

能量受限的单移动设备无线充电调度算法

基于磁耦合谐振的多节点充电技术为解决无线传感网络的健壮性问题提供了潜在的解决方法。为了减少充电设备的移动能耗,保证充电规划的可调度性,结合磁耦合谐振的充电效率,采用蜂窝网状结构将网络分割成若干充电区域,提出了基于移动充电设备的无线传感器网络充电调度算法。由于实际的移动设备能量通常有限,在每个充电周期内综合考虑移动设备能量、节点剩余能量等,提出了自适应动态算法以自动选择k个充电区域。规划充电路径时,采用实时性较好的弹性网络算法来满足网络节点的充电需求。仿真结果表明,充电设备能量的大小会直接影响网络的总能量与最小剩余能量,算法在设备能量有限时能够最大化网络的最小能量,延长网络的生命周期。     

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。