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《科技通报》2015,(10)
为了提高云计算环境下网络资源访问和调度能力,需要增强网络资源的活跃度,传统方法采用源信息系统最小方差粒子群优化算法实现资源活跃度增强调度,直接交互式多源信息的缺陷,导致信息访问的滞后和时延。提出一种基于粒子群(PSO)递阶进化的多出口网络资源活跃度增强算法,构建多出口网络资源调度和网络系统结构,粒子群进化按照属性的数据波动进行递阶分层,得到一个资源数据聚类的高密度区域,使得每一个初始种群中的个体都应有一个解,在多波束搜索PSO空间中实现粒子群PSO递阶进化,提高网络资源访问的活跃度。仿真实验表明,采用该算法,能避免粒子群在进行网络资源搜索调度过程中陷入局部最优,有效提高控制搜索精度,运行时间较短,能有效增强多出口网络资源的活跃度,进而提高了资源搜索成功率。 相似文献
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《科技通报》2015,(12)
通过对云资源平台的自适应调度设计,优化整合云存储空间资源,提高系统的运行效率和资源利用率。在云资源平台任务执行中收到用户行为特征干扰因素较多,调度响应出现时滞,传统方法采用基于时间尺度分析的云资源调度方法,当资源出现随机性干扰时受到网络延迟的影响较大,性能不好。提出一种基于量化特征提取的云资源平台自适应调度方法。构建资源调度平台的总体框架结构,进行资源信息特征提取,采用云资源量化特征提取结果作为调度系统的输入函数,对多源资源信息系统访问特征进行最小方差估计,整个调度过程是一个严平稳的随机过程,通过量化特征提取,能保证对云资源各个调度节点的遍历历经性,提高调度准确性。仿真结果表明,采用个算法能有效实现对云资源平台的自适应调度,抗干扰能力强,资源利用率较高。 相似文献
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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
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《科技通报》2015,(10)
对私有云计算平台上资源最优路径匹配,实现对资源的有效调度和检测,提高资源共享能力。传统算法采用云平台的资源置换算法实现云资源目标匹配,受限于机器学习技术自身的复杂性,性能不好。提出一种基于委托管理节点角色量化合成的私有云计算平台上资源最优搜索路径匹配算法。构建私有云计算平台终端数据访问和资源调度模型,根据贪心算法的收缩原则,在资源访问管理中引入互斥锁机制以保证资源共享操作的完整性,路径匹配有向图模型,提高资源路径匹配搜索能力。以全局度量为中心节点,计算逆向追踪搜索频度,实现算法优化。仿真实验结果表明,采用该算法进行私有云计算平台上资源最优路径匹配优化,能有效提高私有云平台上的资源路径匹配准确度,从而提高资源搜索成功率,实现资源优化共享,展示优越的适用价值。 相似文献
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在已知的线性模型中,考虑加权最小二乘估计与线性无偏最小方差估计的结果的差异。发现在两种条件下,加权最小二乘估计与线性无偏最小方差估计的结果趋于一致。 相似文献
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云计算下虚拟信息资源大数据特征集成调度 总被引：1，自引：0，他引：1
《科技通报》2015,(10)
研究大数据环境下基于云计算的虚拟企业信息系统构建和调度模型,通过对云计算环境下的虚拟企业信息资源特征集成调度,提高数据访问和管理能力。传统的集成调度方法采用层次分析法,通过粒子群(PSO)算法进行虚拟企业信息管理存储系统的任务调度,存在信息管理迟滞等问题。提出一种基于模糊循环堆栈控制的虚拟企业信息管理资源信息特征集成调度算法,把虚拟企业信息管理资源信息调度网络的能量节点进行模糊循环堆栈控制设计,得到虚拟企业信息管理资源信息调度配置的权值,实现对虚拟企业信息管理资源的大数据特征融合和集成。仿真实验表明,该算法能有效提高虚拟资源大数据特征集成调度成功率,执行时间缩短,具有较高的应用价值。 相似文献
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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
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《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
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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
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《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
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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
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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
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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
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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
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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
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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