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1.
基于链路同态解析的WSN路由选择算法 总被引：3，自引：0，他引：3
《科技通报》2015,(8)
通过优化无线传感器网络(WSN)的路由选择算法,实现负载均衡,节省WSN节点的能量开销。传统的路由选择算法使用基于汇聚节点随机链路分析的路由选择算法,控制网络中节点的密度实现路由选择,算法受到外界干扰较大,性能不好。提出一种基于链路同态解析的WSN路由选择算法。设计WSN节点的能量调度算法,提取网络传输的数据多路复用器输出端口的数据,找到经过最短路径数目最多的边并将它从网络中移除,采用能量剩余度同态解析模型,把WSN的能量节点变换到链路同态解析波束域中,实现WSN路由选择算法改进,实现WSN节点的能量调度,提高WSN的负载均衡能力。仿真结果表明,该算法能优化WSN的路由选择,节点的平均能量消耗最低,提高了WSN的可靠性和生存周期。 相似文献
2.
无线传感器网络WSN的路由存活概率云计算模型的优化设计可以提高WSN网络的网络复杂和数据吞吐量,在WSN网络的路由发射功率能耗具有匹配衰减特性,路由存活概率优化困难。传统方法采用灰色马尔可夫链组合模型进行存活概率预测,云计算精度不高。提出一种基于不变波束形成的WSN路由存活概率云计算优化模型,进行WSN网络云计算路由链路模型的结构设计,在WSN网络中进行任务节点信息表征,采用能量剩余度向量概率密度优化分配算法进行能量分配,把WSN的能量节点信号从阵元域变换到波束域得到阵列域,采用空间协方差矩阵逆的高阶次幂来逼近WSN的数据传输信号模型,将旋转角度控制在半功率主瓣以内,由此得到了云计算模型下WSN路由节点数据传输模型。仿真实验表明,该算法能提高WSN路由的存活概率,从而提高了WSN的吞吐量和通信能力,路由概率寻优中抑制了在WSN网络的路由发射功率能耗的匹配衰减性,通过最小的能量开销实现路由分发速率和负载效益的最大化。 相似文献
3.
通过对无线工Ad Hoc网络中的动态源路由协议AODV进行了深入的研究,包括协议过程和报头格式,并且分析了AODV协议在能量问和负载方面所存在的问题;提出了无线Ad Hoc网络中基于AODV路由协议的能量和负载均衡的EAODV协议.EAODV协议考虑了节点的剩余能量和节点的已使用缓冲区大小两个度量,使之支持能量均衡和负载均衡,仿真结果表明EAODV协议有效地均衡了AODV路由协议的能量消耗和节点的负载,延长了网络的生存时间. 相似文献
4.
在多媒体无线传感器网络中,网络信道密集,路由表转发和链路估计过程中会在网络密集信道中产生间歇性混叠谱。混叠谱频段消耗大量能量,需要对间歇性混叠谱频段的功耗进行负载均衡设计,提高网络的生存能力。提出一种基于路由引擎链路转发机制的网络密集信道间歇性混叠谱频段功耗测试方法,实现网络的负载与功耗的均衡。构建WMSN路由节点数据传输模型与网络模型,分析网络密集信道中的间歇性混叠谱的产生激励及能量消耗计算方法,得到无线传感器网络中各个节点发射信号能量脉冲偏移,计算路由引擎链路转发机制下的间歇性混叠频段联合特征均方误差,实现网络的负载与功耗的均衡,达到网络密集信道中间歇性混叠频段功耗测试的目的。仿真实验表明,该算法具有较好的功耗负载均衡性能,传输相同多媒体视频信息数据,功耗测试表明算法能节省能量开销45%,从而提高了网络的生存能力。 相似文献
5.
为了提高无线传感器网络的能量利用率和延长网络的生命周期,本文提出了基于负载平衡的无线传感器网络路由算法。首先,将网络划分成多个网格,根据网格内节点的负载情况定义网格的状态,结合网格的地理位置和网格负载状态选择路由网格;其次,根据节点剩余能量和负载大小在选择的网格内选取一个合适的节点开始数据的收发工作;最后,通过模拟实验将本文算法与GPSR算法和GEAR算法进行比较。仿真结果表明,该算法有效改善了网络的负载均衡,延长了网络的生存期,并提高了网络的吞吐量。 相似文献
6.
基于LEACH协议,提出WSN改进分簇路由算法。该算法能根据节点的剩余能量和节点到基站的距离在无线传感器网络中选出簇头,再由接受信号的强度确定成簇规模不超过最大成员数的簇成员节点,并依据所选簇头的自身条件动态决定是否需要在簇内产生助理簇头,进而在需要的簇内选择合适的节点作为助理簇头。根据理论分析,改进算法能均衡网络负载,降低网络能耗,延长网络生存时间以及提高网络运行周期。 相似文献
7.
张赟 《大科技．科学之谜》2013,(20):354-355
在无线传感器网络中，分簇路由协议相比于平面路由协议具有一定优势，因此对于分簇路由协议的研究具有重要意义。本文将网络中节点的位置信息与节点的剩余能量相结合，基于LEPS路由协议从工程角度提出一种改进方案E-LEPS路由协议，并讨论了其工作过程。 相似文献
8.
无线传感器网络WSN发射功率的优化调度是决定WSN使用寿命和提高WSN性能的关键,WSN路由节点的在进行数据转发时会导致热点随机扩散,发射功率无法难以实现最大化。提出一种基于路由热点循迹修正的WSN发射功率调度算法。设计了WSN节点路由热点循迹数据传输模型,对发射功率消耗能量模型采用一个高斯衰减信道建模,采用直线反馈线性化补偿方式对路由热点的偏移轨迹进行超负荷状态评估,采用贪婪算法生成一条多分簇路由链,对路由循迹轨迹进行修正,得到WSN优化发射功率的调度递推公式,实现能耗最佳的功率优化调度。实验结果表明,采用该优化调度方法,在准确实现热点循迹修正,传输功率较传统方法稳定,波动较小,WSN可靠性和生存性增强。 相似文献
9.
《科技通报》2015,(10)
设计高速网络流路由修复算法,提高网络的生命周期,降低路由节点能耗。传统的路由修复算法采用阈值分割路由冲突分解算法,采用阈值分割判断实现路由修复,无法有效满足高速网络流路由修复的应用环境。提出一种基于断点损耗预测的高速网络流路由修复方法。计算通信节点的衰减性能,绘制出符合高速移动环境移动节点衰减曲线,根据欧氏距离公式计算出随机分布的路由节点的路径链接的稳定性,对多角度系数进行修订,采用断点损耗预测方法,进行功耗损失修订,实现路由修复。仿真实验表明,该算法实现高速网络流路由修复。有效地控制簇头的数量和分布、节约能量、均衡网络负载,提高了高速网络流路由的生命周期,单个节点能耗大幅降低,在高速移动大规模网络流维护和路由控制优化中具有较好的应用价值。 相似文献
10.
AODV路由协议以最短路径优先为原则,在节点负载的方面存在着不足之处,AODV路由协议是路径最短协议,却不是性能最优协议。为减轻路由负载,提高协议性能,提出了一种新的路由寻路算法,在路由发现过程中考虑各个节点的负载情况,通过丢弃负载过高节点,避开负载过高节点,从而实现整个传输系统的负载均衡。仿真结果表明改进的协议与原AODV协议相比,降低了端到端时延,提高了包传输率,网络传输性能得到改善。 相似文献
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
13.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
15.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
16.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
17.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
18.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献