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1.
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
2.
半干旱草地净第一性生产力遥感模型研究 总被引：2，自引：0，他引：2
本文采用MODIS遥感数据，针对内蒙古半干旱草场生态环境特征，以光能利用率模型为基础与生态模型相结合，研究区域尺度下半干旱草地净第一性生产力(NPP)遥感模型；利用草场植物生长过程中从光合和呼吸作用出发的NPP遥感模型与从植物生物量和衰败量变化出发的GNPP模型的估算值之间构建代价函数，有效地对模型参数进行估算和校正；模型考虑了气温和植物水胁迫的影响，以及时空尺度的差异，并充分利用遥感反演的参数来驱动。模型经内蒙草场MODIS数据、实测数据、相关模型的验证，结果表明，模型参数校正能提高模型估算的精度，且NPP估算精度满足实际应用需要，此遥感模型合理可行。 相似文献
3.
[研究目的]为实现科技政策文本内容的自动编码与多主题分类,探索一种融合BERT模型和多尺度CNN模型的多标签分类方法,得到更加丰富的政策语义特征信息。[研究方法]针对科技政策内容句的信息密度大、内涵分布不均衡等特点,通过BERT充分提取政策内容的上下文信息,增强文本的语义特征表示;然后利用多尺度、多通道的CNN-Inception模块提取更多尺度的特征,通过捕获文本的局部特征与组合不同尺度的语句特征,提升模型在多标签分类任务上的性能。[研究结论]对比实验表明,与单一BERT分类模型相比,文中提出的BERT-多尺度CNN模型的召回率与Micro-F1值显著提高,提升了科技政策多标签分类的效果。 相似文献
4.
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
5.
随着测绘地理信息行业的发展，基础测绘产品体系和技术手段不断升级完善对原有的测绘范围、内容和方式方法以及相关支撑服务都有新的要求。为满足测绘地理信息行业各项统计调查任务数据采集和分析需求，设计面向测绘地理信息统计业务的准实时数据仓库架构、业务主题以及存储模型等。其中，数据仓库架构包括两个加载触发器，将历史数据仓库加载数据的触发器放置在实时数据仓库规模达到5 000条时,能够使得联合统计分析获得较高性能；根据测绘地理信息统计频率，基于季度、半年和年度3个主题域构建了3套多维数据模型；最后，对不同特征的数据采取不同策略，经过抽取、清洗和转换之后加载到数据仓库并清空实时数据仓库。依托测绘地理信息统计准实时数据仓库，初步应用实践表明，测绘地理信息统计网络直报系统实现节点汇总、综合查询和批量分析功能，有效提高数据采集、统计分析的效率和效果。未来，测绘地理信息统计工作应及时升级现有的数据仓库模型和分析手段，重点关注数据信息安全。 相似文献
6.
作为网络安全产品的基于隔离技术的隔离网闸越来越受人关注，隔离网闸自带的文本内容过滤大多基于关键字过滤和URL过滤．这种内容过滤在使用性能上不但过滤效果欠佳且效率差，已不能满足日益增长的网络信息的安全要求；研究了文本信息过滤的模型、文本预处理技术、文本特征选择技术、过滤算法，提出了基于统计的适合于隔离网闸的智能文本过滤的方案，并对新方案中的关键技术加以研究和实现。 相似文献
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8.
提出一种基于最大熵功率谱估计的Hadoop云平台下网络音视频数据特征挖掘方法,实现对数据信息的高速访问。构建数据挖掘Hadoop云平台和数据挖掘访问模型,设计最大熵功率谱特征提取算法,采用分段思想将同一时间段的视音频数据进行群体分割,分段提取最大熵功率谱特征。将提取的特征信息进行维度匹配分箱和溯源处理,实现信息恢复,最终完成高速数据访问。仿真测试表明,该算法能有效地实现对网络音视频数据的特征挖掘,提高访问效率,访问响应时间较当前方法缩短明显。 相似文献
9.
《科技通报》2015,(8)
在数字化信息系统中,将大量网络计算资源、存储资源与软件资源等多源信息资源进行多层次异构存储,对信息资源的调度和检索成为难题。传统的多源信息检索方法采用概念格差异融合算法,无法有效识别差异化网络数据的语义特征,检索性能不好。提出一种基于概念格特征分区的多源信息检索优化算法。概念格的生成是进行数据分析、关联分析和挖掘关联规则的前提,首先给出概念格的构造模型,进行概念格特征分区,得到数据库集合的特征概率函数密度,构建满足约束条件的无冗余概念格,计算多源信息的两种相似度系数,挖掘约束关联规则,提高信息检索精度。仿真实验表明,该算法实现多源信息检索性能优越,无偏性好,精度较高。 相似文献
10.
研究滑坡模拟系统所需的基本数据源，为滑坡模拟提供数据基础；研发基于地质灾害调查信息系统的滑坡三维动态模拟工具，建立表达三维数字滑坡体的基本图元；在总结区域地质环境、滑坡特征和滑坡稳定性评价的相关成果基础上，以库区不同类型边坡及滑坡稳定性评价模型为原型，实现在多种外力作用下滑坡过程动态模拟。 相似文献
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.
《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
14.
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
15.
《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
16.
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
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