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1.
在移动学习过程中,需要对云资源信息流节点准确定位,提高网络学习效率,增强学习网络转换信道均衡能力。传统方法中采用基于向量随机学习的网络信道切换队列整合方法,实现对信任节点的定位,但当出现信任时隙局部性交叉项时,定位性能不好。提出一种改进的面向移动学习的云资源信息流无源定位技术。采用M-learning随机场学习模型,通过局部性交叉项补偿进行信息链单流量解析模型设计,在大数据环境下,对信任节点的数据种类进行无源定位分类,然后通过云资源信息流节点任务调度方法,提高网络的信任度,由此提高对云资源信息流的无源定位能力。仿真结果表明,该算法能有效提高对M-learning环境下的云资源信息流的定位精度,提高学习效率和资源分配能力。在学习资源共享调度等领域具有较好的应用价值。  相似文献   

2.
杜巍  高长元 《情报科学》2017,35(10):23-29
【目的/意义】移动互联网时代,移动电子商务用户的个性化信息需求具有极强的情景依赖性与感知信任 性,针对目前移动商务信息服务个性化和准确性较低,提出融入用户个性化情景与用户间信任关系的推荐模型。 【方法/过程】首先,通过用户当前情景和历史评分数据计算出对每个用户即时信息需求影响最大的K个情景要素, 以此构造用户个性化情景,然后结合不同信任环境下的用户信任度矩阵改进已有的不同信任信息环境下用户情景 兴趣推荐方法,进而进行项目推荐。【结果/结论】通过Movie lens与Book-Crossing数据集对本文提出的算法和其 它两种算法进行比较,实验结果表明:本模型具有较高的推荐准确率,可有效地解决移动商务环境下的个性化推 荐问题。  相似文献   

3.
网络用户信任感知推荐的准确性设计是提高用户间的社交网络辅助信息信任度的重要依据。传统的网络用户信任感知推荐算法采用的是基于社交网络服务和用户评分的推荐系统,主观性较大,协同过滤效果不好。提出一种基于网络动态干扰监控的信任感知推荐算法设计新方法,设计自适应神经模糊系统网络动态干扰监测算法,构建基于向量空间模型的信任度评价指标体系结构,通过调整网络拓扑权重向量设置信任度周期响应加权变量自适应函数,有效降低迭代算法的运算成本,避免了自适应神经模糊系统网络动态干扰监测加权权重成固化状态,提高抗干扰性能。实验结果表明,算法能使社交网络感知推荐模型的预测误差减少,推荐可靠性优于传统方法。  相似文献   

4.
推荐系统已经成为人们在网上寻找自己所需信息的常用工具之一。基于社交网络的推荐方法能够解决传统推荐算法存在的问题,例如新用户的冷启动问题。本文提出了一种基于矩阵分解的并且可以应用于社交网络的新模型。该模型将信任传播机制融入模型中,并使用Epinions.com数据集进行实验。试验结果表明,基于社交网络的新模型在推荐准确度方面相较于传统模型,针对评分较少的新用户所存在的冷启动问题有较好的解决。  相似文献   

5.
王帅 《科技广场》2012,(6):22-27
本文提出了一种新的P2P网络信任模型——层次化分布域信任模型HDRTM。该模型基于历史交互信息和信誉推荐,采用量化方法和合成规则方法得到的信任度对P2P网络中的节点信任进行评估,同时引入了惩罚调节因子、合成规则权重因子等加强了信任度的可靠性与真实性。对HDRTM的仿真证明能够有效抵制恶意节点,具有较好的安全性与信任性。  相似文献   

6.
个性化E-Learning平台的设计与实现   总被引:1,自引:0,他引:1  
E-Learning是指利用网络或其他数字化资源进行的学习与教学活动,它可以充分利用现代信息技术所提供的全新沟通机制与丰富资源,实现学习方式的变革。本文基于MVC框架,开发了E-Learning平台,主要包括资料上传、用户信息收集、离线挖掘和在线推荐等几个功能模块,不但可以实现常规的远程教学和培训,而且可以实现个性化推荐服务。  相似文献   

7.
根据用户的个性化需求进行网络信息推荐,在电子商务商品推荐和网络信息推送中具有应用价值。本文针对传统的语义关键词推荐方法的指向性精度不高的问题,提出一种基于协同过滤融合和个性化特征约束校对的信息推荐算法,首先构建P2P网络模型下的信息传输模型,对用户的个性化需求信息进行信息融合和语义信息素特征提取,然后采用自相关匹配滤波方法进行信息融合和滤波,实现对个性化特征的协同过滤和信息推荐,最后通过仿真实现进行性能测试。仿真结果表明,采用该算法进行信息推荐的数据召回率和配准度较高,耗时较短,实现个性化信息定制和推荐。  相似文献   

8.
针对企业对实时个性化推荐的需求,基于信息流的表达、生成和分析对顾客访问记录进行了深层次挖掘,研究了电子商务系统实时个性化推荐策略,提出了包含信息流定义、信息流评价、知识匹配、网站动态组织等算法在内的个性化推荐算法.基于J2EE技术完成了包含客户端、服务器端和存储系统在内的实时动态个性化推荐系统的结构设计.实例表明,随着训练次数的增加推荐准确度呈升高的趋势,并优于关联规则法.  相似文献   

9.
基于SOM的图书馆用户个性化数字信息服务需求分类研究   总被引:1,自引:0,他引:1  
针对目前图书馆个性化数字信息服务中用户需求模型构建存在的问题,将SOM人工神经网络算法引入模型构建过程,利用其动态适应能力提高模型分类的准确性。根据用户对个性化服务内容的需求程度进行打分,挖掘用户的偏好,以网络调查问卷数据作为训练和测试样本,对用户需求进行学习分类,并验证其准确性。  相似文献   

10.
王槐源 《科技通报》2015,(2):227-229,246
在对波段性网络入侵差异化特征进行提取的过程中,会出现入侵差异化特征伪装程度逐渐升高的情况,导致传统的基于敏感性数据挖掘的波段性网络入侵差异化特征提取方法,由于不能有效区分入侵特征与正常特征,无法有效实现波段性网络入侵差异化特征的有效提取,提出一种基于支持向量机的波段性网络入侵差异化特征提取模型,获取不确定入侵中波段性网络节点的差异化特征以及入侵节点,给出两种不确定入侵中波段性网络节点的差异化特征训练数据样本集,通过非线性映射将数据样本集从原空间映射到高维特征空间中,得到高维特征空间中最优线性分类面,采用支持向量机求解该分类面的优化解,使用网格搜索法,通过调整错分惩罚因子与核宽度,分别训练不同的支持向量机,获取泛化能力最强的参数组合,完成入侵中波段性网络节点的差异化特征所对应的数据集的核参数优化和分类,实现波段性网络入侵节点的差异化特征的有效提取。仿真实验结果表明,所提方法具有很高的准确性及有效性。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

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.
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.
Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms' spin states (Phys. Rev. Lett. 99 130403).  相似文献   

19.
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   

20.
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   

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