共查询到20条相似文献，搜索用时 93 毫秒
1.
《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
2.
在网络安全预测监护模型设计中,需要对网络安全监护信息进行数据融合和特征优选,以提高对变异特征的识别能力。传统方法中,采用蚁群算法进行监护信息特征优化融合进化和链路模型设计,算法无法实现相邻簇头之间的信息素融合,特征优化效果不好。针对这一问题,提出蚁群链运动多层博弈的网络监护信息融合特征优选算法,构建多层博弈网络监护数据样本驱动空间权矩阵模型,引入粗糙集理论,对蚁群引导的粗糙集前馈补偿网络进行动态博弈,实现网络安全监护数据的预测控制目标函数最佳寻优。构建多层博弈网络监护系统模型,得到蚁群链运动的监护信息数据状态跟踪模型,实现网络安全监护信息的融合特征优选改进。仿真实验表明,该算法能有效提高对异常信息的监护和检测能力,有较高的特征优选品质,展示了本文算法在对网络安全监护中的优越性能。 相似文献
3.
为了提高对网络异常流量监测模型的置信度和准确性,降低虚警概率,防止漏报。需要对异常网络流量预测概率置信度区间进行优化设计。提出一种基于预测流量数据主特征建模与广域子空间重构的异常网络流量预测算法,提高预测概率置信度。把主特征建模投影到广域子空间中,获取网络异常流量数量的对偶子梯度预测结果,其表现为一组尺度,分析网络预测流量的概率置信度的伸缩变化,选用极大似然法对网络流量的预测概率置信度进行特征建模,得到概率置信度区间。提高预测置信度和精度。实验结果表明,该算法能有效提高异常网络流量的预测精度,通过在广域子空间中特征建模,保证了预测的概率置信度,减少预测误差,性能优越。 相似文献
4.
网络数据流量的准确预测是评判和选择最佳Web服务的一种重要标准。传统的网络数据流广域子空间流量预测方法没有进行分解降维处理,预测误差较大,无法对大跨度的网络流量进行准确预测。提出一种基于广域子空间分解降维的网络数据流量准确预测方法,把网络流量数据流构建广域子空间进行预处理,在广域子空间中对数据进行分解分析,把提取的高维特征涵摄在广域子空间中,进行广域子空间分解降维,然后将广域分析的结果与子空间降维分析的结果进行有效的数据融合,实现对整个网络流量分析数据的准确预测。仿真测试表明,采用基于广域子空间分解降维的方法进行网络数据流量预测,可以精确预测网络流量渐变过程,结果准确,且计算开销明显降低。 相似文献
5.
《科技通报》2015,(10)
设计网络流量预测数学模型,实现对网络流量的准确预测和评估。传统的流量预测算法采用包络特征子空间聚类的流量序列分析方法,对随机大数据网络流的聚类和预测效果不好。提出一种随机阵列向量模型的流量预测算法。首先进行了网络流量预测的时间序列模型构建,采用平均互信息算法和伪最近邻点法求解最优化网络流量序列重组空间异构参数,得到一个高密度流量数据分形区域,创建流量序列的概率分布曲线,在随机阵列相空间中形成新的映射采用统计学数学方法对流量序列的随机分布特征进行分布式计算,随机阵列向量模型构建方法进行流量预测算法改进。仿真结果表明,采用该算法进行流量预测,能有效提高预测精度,具有较好的流量特征分析能力,性能优越。 相似文献
6.
在能量受限的侦听网络中,需要大量的信息交换,由于瓶颈节点的能量消耗无法满足侦听网络的流量需求,需要进行流量扩张模型构建。传统方法采用对偶子梯度法实现对侦听网络的流量扩张,方法只能考虑一种流量和节点的组合,适应性能不好。提出一种基于小波变换尺度耦合特性分析的侦听网络流量扩张模型,对侦听网络流量时间序列进行采集与分析,通过小波尺度耦合分析,对路由接收的调度任务指令数量做出有效预测,从而为调度模型的建立提供准确的数据基础。分析流量序列的瞬时频率线性变化规律,得到带宽频间谐振模型,通过小波尺度耦合特性约束,提高了流量的流通量,实现流量扩张。仿真结果表明,算法能有效提高侦听网络的数据流吞吐量,网络流量通道得到有效扩张,提高了侦听网络的安全性和通信效率,展示了较好的应用性能。 相似文献
7.
8.
网络并发式流量特征具有信号时间可预测性,通过对网络流量的解卷积测度特征提取,提高对网络流量的预测性能。传统法方法采用粒子群优化算法实现对网络流量的特征测度盲解卷积分析,对原始信号的统计信息提取效果不好。提出一种基于粒子群退化重采样的网络流量解卷积测度提取算法,构建并发式网络流量序列采集模型,设计粒子退化重采样技术,将每个粒子的当前适应度值与其自身的个体最优值进行比较,如果优于个体最优值,得到粒子当前最优位置。仿真实验表明,采用该算法,收敛速度很快,在粒子群进化50代以内就可以实现成功收敛,对流量序列的测度特征提取结果准确,预测精度较高,展示了算法的优越性能。 相似文献
9.
基于包络特征的网络流量预测阈值调控算法 总被引：1，自引：0，他引：1
《科技通报》2015,(10)
对网络流量序列的准确预测的基础是进行流量判决门限阈值的合理调控,为了提高网络流量预测的精度,进行阈值调控优化设计。传统方法采用流量序列调频估计的方法进行阈值调控,算法不能准确估计流量序列的包络特征,预测精度不好。提出一种基于包络特征的网络流量预测阈值调控算法。通过不同类型的网络设备进行流量采集终端联网构建,采用自相关特征奇异分解对流量序列进行线性特征叠加运算,构建网络流量预测的时间序列模型。采用统计学数学方法对流量序列的延迟时间互信息进行阈值调控自适应建模,提取流量序列的包络特征。实现对网络流量预测的阈值调控,提高预测精度。仿真实验表明,该算法能实现对流量预测阈值的自适应调控,预测精度较传统方法提高37%,性能优越于传统算法。 相似文献
10.
11.
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
12.
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
13.
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
14.
《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
15.
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
16.
《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
17.
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
18.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
19.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
20.
Leah A. Lievrouw 《The Information Society》1998,14(2):83-96
The main premise of this article is that in information societies generally, and in virtual social contexts particularly, a distinctive style of interaction to facilitate the communication of difference, heterotopic communication , has emerged. It rests on two cultural foundations: an ideological belief in the positive, socially integrating power of communication, and a prevailing ethic of instrumental rationality, subjective individualism, and strategically practiced self-interest. The former is demonstrated by the use of simulation and spectacle as sources of information; exhibitionism/voyeurism as a communicative style; and the awareness of surveillance. The latter is seen in the competitive use of knowledge as a commodity; a surface globalism masking deep parochialism; lateral as well as vertical information inequity; and the use of public versus private as strategies for engagement rather than as spaces. Those who engage in heterotopic communication resort to their 'own devices' both in the sense of personal agendas, strategies, interests, and interpretations, and in the form of the telecommunication tools that help realize them. These personal and technological devices allow individuals with the right educational and technical resources to avoid exposure to disagreement, difference, or other information that does not serve their direct purposes or reflect their particular views of the world; yet they also help convey the appearance of openness, availability, and cooperation. This style of interaction is used strategically in combination with information and communication technologies to gain social or economic advantages, but it may encourage social separatism and parochialism, inhibit the negotiation of disputes, and emphasize competing interests. 相似文献