共查询到20条相似文献，搜索用时 59 毫秒
1.
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
2.
高可靠性和预警概率的救灾预警系统是保障现代化发展免受灾害破坏的重要手段。传统的救灾预警系统无法挖掘出数据之间的相关信息。提出一种Android平台下基于多状态模型的高预警率物联网救灾预警系统,将各节点采集的数据传输到统一平台上,建立不同节点的多状态模型,然后在模型基础上采用数据挖掘的方法,提取各平台多状态模型数据之间的相关信息,通过模型融合后的总体判决,实现预警。最后采用一组10节点的网络进行性能测试,结果显示,基于物联网的多状态数据融合预警系统将正确预警率提高到了98%,远高于传统的65%,具有很好的工程应用价值。 相似文献
3.
在CStor云数据库访问中,细粒度云存储数据的信息特征存在个体较大差异,访问路径产生多频偏移,数据访问调度性能受限。传统方法中采用PSO局部搜索方法进行访问路径修正,搜索效率低,个体更新较慢。提出一种基于细粒度云存储数据迭代恢复匹配的云数据库访问路径偏移修正算法,以PSO多信息融合Pareto支配集为指导,构建多信息融合细粒度数据的主特征模型,采用迭代恢复匹配方法增加了局部搜索提高搜索到全局最优解的几率,实现路径偏移修正。仿真实验采用3组测试集对CStor云数据库进行访问调度和路径偏移修正,结果表明采用该算法,实现对访问路径的动态实时修正,收敛距离较小,提高了CStor云数据库访问和数据挖掘性能。 相似文献
4.
架空输电线路铁塔结构是我国主要的输电方式,一旦发生损伤破坏将造成严重的经济损失。本文提出了一种基于随机森林的数据融合架空输电线路损伤识别方法。首先,采用多个传感器获取铁塔在不同损伤位置和程度上的振动加速度信号,并运用小波包对其进行多层分解;然后,将提取出来的各频带能量值构成特征向量输入到相应的随机森林进行训练和测试;最后,将多个随机森林分类器的次级决策进行数据融合,做出最终铁塔损失情况决策。应用该方法对500kV高压输电铁塔模型进行试验,并与单一分类器相比较。通过对实验数据的分析表明,该方法对铁塔损伤的识别效果优于单一RF分类器,可以有效地改善单一分类器的识别能力。同时也表明该方法具有较好的分类效果和容错能力。 相似文献
5.
无论是在实体足球比赛还是智能体机器人足球比赛中,近距离的任意球破门收益率较高。研究智能体足球机器人比赛的任意球轨迹修正和优化控制问题,进而指导足球训练提高任意球得分率。提出一种基于灰色靶关联分析的智能体任意球轨迹修正方法,首先对整个机器人足球的环境态势和球员行为体选择进行模型构建,然后给出了灰色靶关联分析的任意球轨迹修正算法,进行球体着力点和应力点的适应值分析,构建基于灰色靶关联分析的任意球应力衰减特性分析模型,指导任意球轨迹修正,最后在智能体足球世界杯3D仿真平台进行实验验证了算法的优越性能。实验结果得出,采用该算法能有效指导任意球发球着力点控制,优化任意球的攻击轨迹,提高智能体机器人足球的任意球进球成功率,预测和控制精度提高。 相似文献
6.
7.
基于融合基础架构的新一代数据中心,提出一种基于融合特征空间构架的云数据离散调度逼近算法,在对系统节点进行数据采集任务分配的基础上,研究基于云计算的IAAS层基础设施自动化快速供应的技术方案,对云数据离散分配任务进行评价和估计,描述了云数据采集和特征空间融合架构方法,构建云数据采集和特征空间融合机制,进行融合特征空间构架下的数据离散调度逼近算法改进设计。研究结果表明,该方法实现云数据离散调度的压缩性能很稳定,有效节约了任务执行时间,云数据离散调度逼近的收敛步数较少,收敛性好,展示了较强的实用性和优越性,为云计算的顶层设计PAAS与SAAS提供技术平台支持。 相似文献
8.
《科技通报》2016,(3)
研究多源语义特征分层数据库中的大数据聚类方法,实现数据的分类识别。多源语义特征分层数据库中由于路由冲突,在链路负载较大的情况下,不能有效实现对大数据语义特征的并行搜索。提出一种基于增广链同态解析的链路分流方法避免路由冲突,实现增广链修复下大数据并行搜索聚类。构建大数据聚类的语义相似度融合模型,基于跨层链路分流算法实现增广链路分流,进行语义本体模型构建,选择采用高阶贝塞尔函数累积量作为增广链修复检验统计量,确定节点数据包的置信度,确立置信区间,在进行缓冲区溢出修复时,进行功率谱幅度特征提取,实现大数据的并行搜索聚类,进行语义本体模型构建,为离群点新建一个簇,依次对每个文档的主题词集进行处理,将每个主题词自动添加入形式背景的属性集中,采用并行搜索算法实现对语义大数据的优化聚类算法改进。仿真结果表明,采用该算法进行大数据聚类,契合度较高,误分率较低,性能优越。 相似文献
9.
《科技通报》2015,(10)
移动云计算成为一种新兴的数字信息处理技术,是移动通信数据信息处理的重要工具。在移动云计算中,对路由转发分簇簇间的波动离散数据进行量化处理是提高云计算并行数据分析效率的关键。传统方法采用时延估计方法进行量化处理,当用户信道分配出现时滞时,量化性能较差。提出一种基于贝叶斯粗糙集估计的移动云计算簇间波动离散数据均匀量化算法。构建移动云计算数据分簇模型和信道模型,进行波动离散数据采集,按照Logistic模式选择路径,得到移动云计算簇间波动离散数据均匀量化的最优概率密度,构建贝叶斯粗糙集均匀量化优化目标函数,实现算法改进。仿真结果表明,采用该算法能有效实现对移动云计算簇间波动离散数据的特征分类,对波动离散数据的量化效果较好,从而提高了云计算的并行计算效率。 相似文献
10.
本文研究了飞机副翼卡死故障下飞机的应急路径规划问题。应急路径规划可以归结为求解带有约束条件的多目标函数的最优问题,采用遗传算法选择平衡轨迹库中的一些轨迹段序列得到一条完整的降落航迹。通过对F16飞机非线性模型进行仿真,验证了方法的有效性。 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.
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
16.
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
17.
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
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