共查询到20条相似文献，搜索用时 78 毫秒
1.
为开发高效的数据挖掘算法,实现模糊集聚类算法的高效性,将BIRCH聚类算法思想与模糊集算法进行融合。通过对模糊集算法处理的数据进行二次聚类计算,细化群边缘,最后加载判别函数进行数据定位,完成数据挖掘。最后使用KDDCUP2011数据库进行仿真实验,对目标数据进行挖掘,证实了融合BIRCH聚类算法思想的模糊集算法具有可行性,对比改进前的算法在数据挖掘方面效率更高。 相似文献
2.
《科技通报》2015,(8)
对云计算系统中的漂移数据中心分类区的准确确定,可以提高云计算系统的扩展能力和缓存能力。传统方法采用线性差分智能群识别方法实现中心分类区的确定,导致漂移数据的群辨识效果不好。提出一种基于粒子群聚类的云计算系统中数据中心分类区的确定算法模型,并进行仿真实现。构建云计算系统网络激励传播机制,实现资源负载均衡,把云计算系统的存储数据结构定义为一个四叉树,构建云计算网格环境下空间资源调度框架体系,进行云计算系统的漂移数据特征提取,使得资源负载均衡达到最优值,实现算法改进。实验得出,模型对云计算系统的漂移数据中心分类区确定准确,数据融合精度较高,聚类性好,云计算系统的扩展指数提高13%,缓存执行能力提高20.5%,展示较好的性能。 相似文献
3.
在无线传感器网络构架下,基于FPGA和KNN粒子聚类算法进行系统控制算法设计,提出一种改进的商场多元安防监测系统设计方案,进行系统硬件层设计、系统软件层设计。功能模块设计中进行了商场环境信息采集模块、火灾自动报警模块、温湿度自动预警模块、烟气报警模块和安全防盗模块设计。软件实现中引入商场火灾、温湿度等信息报警数据融合的KNN粒子聚类算法。算法仿真和系统测试结果表明,该系统对数据融合精度较高,聚类性好,为实现多元安防监测提供准确的数据基础,系统功能健全,实时性好,用户终端界面友好,交互性强,稳定性高,具有非常好的应用价值。 相似文献
4.
《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
5.
《科技通报》2016,(4)
通过对网络流量的准确预测提高对网络的调控和监测水平,避免网络拥堵,确保网络畅通。传统的网络流量预测算法采用粒子群算法,在处理大规模的流量数据时,容易导致信息发散和易陷入局部极值点,流量预测准确度不高。提出一种基于多标记学习混合差分粒子群进化的网络流量预测算法。构建多分簇的无线网络流量数据传输模型,对网络流量进行时间序列分析,采用粒子群优化算法分别比较网络信息流中的频率波动是否相同,对相同的进行合并,基于自回归移动平均算法,进行粒子群信息链特征优选准则设计,采用多标记学习混合差分粒子群进化算法,把网络流量数据嵌入到内核空间的超球体中,进行离线阶段的网络流量预测优化。仿真结果表明,该算法对网络流量预测的精度较高,误差减少,具有较好的应用价值。 相似文献
6.
《科技通报》2016,(8)
二阶锥规划是在有限个二次锥的笛卡尔空间仿射变换交集上的极小化和极大化线性函数,采用修正的二阶锥规划模型,结合二阶锥的凸优化条件,进行大数据聚类算法改进,提高数据的聚敛性。传统方法中对大数据聚类的二阶锥规划模型采用线性对偶锥规划方法,对数据聚类的路径跟踪性能不好。提出一种基于修正的齐次二阶锥规划模型的大数据聚类算法。进行数据的特征挖掘和信息流模型构建,从大量的、有噪声的、模糊的数据中进行大数据的功率谱密度特征提取,采用粗糙概念格方法对大数据信息流进行二阶锥规划模型构建,结合齐次二阶锥规划模型算法有限收敛性,对每一数据聚类样本进行可靠性衡量,实现数据聚类中心的准确搜索。对聚类误差函数求最优解,使得误差收敛到零。仿真结果表明,该算法进行数据聚类的精度较高,收敛性较好,避免了出现局部最优解,性能优越于传统算法。 相似文献
7.
参数的优化选择对支持向量机回归算法(SVR的预测精度和泛化能力影响显著,提出混沌粒子群优化算法(CPSO优化选取支持向量回归算法中参数c和g信息粒化是进行海量数据挖掘和模糊信息处理的有效工具。在此基础上利用上证指数数据建立上证指数开盘数预测模型,研究结果表明,混沌粒子群优化的SVR信息粒化时序回归预测模型克服了传统时间序列模型仅局限于线性系统的缺点,速度快,预测精度高,且实用性强。 相似文献
8.
《科技通报》2016,(4)
针对旋转机械振动故障数据分类挖掘的效率极低、误差率大的问题。为此,提出基于相似性系数与粒子群算法融合的旋转机械振动故障数据优化挖掘方法。以故障数据之间的差异性为依据,对故障数据进行中心化、无量化及标准化处理,以此保证故障数据变量的统一性,为故障数据挖掘提供便利;依据相似系数理论,构建异常旋转机械振动故障数据库挖掘的数学模型,并采用粒子群算法对该模型进行求解,计算旋转机械振动故障数据库挖掘模型的最优解,实现并行数据库故障数据精确挖掘。实验结果表明,采用改进算法进行旋转机械振动故障数据优化挖掘,能够提高挖掘的速度与精度,提高算法鲁棒性,满足了机械振动故障数据库实际的应用需求。 相似文献
9.
《科技通报》2015,(10)
在云计算环境下,针对K-means对初始聚类中心敏感和易陷入局部最优的缺点,进行K-means聚类中心优化求解,提高对海量数据的聚类处理能力。传统方法采用动态干扰信任感推荐方法进行数据聚类中心求解,聚类中心对初始值敏感性较强,数据聚类效果不好。提出一种基于粒子群密度最大距离凹函数构建和边界隶属度特征分析的云计算中K-means聚类中心优化求解方法。通过云计算处理,对数据聚类余下样本点按照与聚类中心的相似程度来划分成k类,对原始变量数据的差异化特征进行降维处理,通过搜索空间中的粒子,每一个粒子自身都有速度、位置和适应度,通过迭代找到最优解,进行数据规范化预处理,数据预处理包括选择数量,类型和特征的标度,进行边界隶属度特征分析,实现云计算数据的聚类改进。仿真结果表面,该算法对云计算数据的聚类性能优越,聚类中心求解准确,克服了传统的K-means对初始聚类中心敏感和易陷入局部最优的缺点,应用价值较大。 相似文献
10.
在对最佳任务调度下的Web数据进行优化聚类的过程中,容易出现原始数据损失的情况,导致传统数据优化聚类算法,由于忽略初始数据,无法有效实现Web数据优化聚类。提出一种基于粒子群优化的最佳任务调度下Web数据优化聚类算法,依据任务价值密度以及执行紧迫性,塑造动态优先级,通过适应度函数对分类计划进行评价,给出类间距与类内距计算公式,对相关参数和各粒子的位置以及速度向量进行初始化操作;求出粒子的适应度;求出粒子个体最优与群最优;依据粒子群优化算法的位置以及速度对当前位置和速度进行更新;通过K-means算法对EHCF进行聚类,直至全部Web数据聚类完成。仿真实验结果表明,所提方法在Web数据优化聚类上具有很高的优越性。 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.
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