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21.
本文首先讨论了开发社区管理系统的必要性和意义,其次分析了社区管理系统的主要功能,再其次设计了社区管理系统的具体模型,接着分析了设计本系统的关键技术,最后对本系统的拓展功能进行了研究。 相似文献
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In this paper, several recent theoretical conceptions of technology-mediated education are examined and a study of 2159 online learners is presented. The study validates an instrument designed to measure teaching, social, and cognitive presence indicative of a community of learners within the community of inquiry (CoI) framework [Garrison, D. R., Anderson, T., & Archer, W. (2000). Critical inquiry in a text-based environment: Computer conferencing in higher education. The Internet and Higher Education, 2, 1–19; Garrison, D. R., Anderson, T., & Archer, W. (2001). Critical thinking, cognitive presence, and computer conferencing in distance education. American Journal of Distance Education, 15(1), 7–23]. Results indicate that the survey items cohere into interpretable factors that represent the intended constructs. Further it was determined through structural equation modeling that 70% of the variance in the online students’ levels of cognitive presence, a multivariate measure of learning, can be modeled based on their reports of their instructors’ skills in fostering teaching presence and their own abilities to establish a sense of social presence. Additional analysis identifies more details of the relationship between learner understandings of teaching and social presence and its impact on their cognitive presence. Implications for online teaching, policy, and faculty development are discussed. 相似文献
23.
针对电子邮件复杂网络中的社团发现问题,将具有良好聚类性能的DBSCAN算法引入电子邮件网络社团发现。基于对该算法的分析,研究了电子邮件网络社团发现的系统架构及算法实现流程。最后通过对安然邮件语料集的测试验证了DBSCAN算法在社团发现中的可行性。 相似文献
24.
Eugenio CapraAuthor Vitae Chiara FrancalanciAuthor Vitae 《Journal of Systems and Software》2011,84(1):144-161
Open Source (OS) was born as a pragmatic alternative to the ideology of Free Software and it is now increasingly seen by companies as a new approach to developing and making business upon software. Whereas the role of firms is clear for commercial OS projects, it still needs investigation for projects based on communities. This paper analyses the impact of firms’ participation on popularity and internal software design quality for 643 SourceForge.net projects. Results show that firms’ involvement improves the ranking of OS projects, but, on the other hand, puts corporate constraints to OS developing practices, thus leading to lower structural software design quality. 相似文献
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Leveraging online communities in fostering adaptive schools 总被引:1,自引:0,他引:1
David Hung Kenneth Y. T. Lim Der-Thanq Victor Chen Thiam Seng Koh 《International Journal of Computer-Supported Collaborative Learning》2008,3(4):373-386
There has long been a call for schools to prepare students for the twenty-first century where skills and dispositions differ
significantly from much of what has historically characterized formal education. The knowledge based economy calls for policy
and pedagogical efforts that would transform schools. Schools are to foster communities of learners. This paper suggests that
para-communities may be points of leverage in the fostering of adaptive schools. A critical analysis is done on the differences
between para-communities (such as online communities) and schools; and an argument is made that they each serve differing
goals and should be left distinct because they achieve different societal and economic demands. 相似文献
28.
A number of studies have examined virtual worlds, which can facilitate knowledge sharing, education, and enjoyment, among others. However, no study has provided an insightful research model for evaluating virtual worlds. This study suggests that users’ identification with virtual communities and avatars plays a critical role in the construction of attractive virtual worlds. The proposed model measures the level of the user’s identification with virtual communities, through which the user builds his or her trust in other community members. In addition, the study suggests that users’ identification with avatars is an important element of their satisfaction with virtual worlds. The results indicate that users’ identification with virtual communities as well as avatars can enhance their efficacy and trust and thus facilitate their sustained use of virtual services. The results have important theoretical and practical implications. 相似文献
29.
Prakash Mandayam ComarAuthor Vitae Pang-Ning TanAuthor VitaeAnil K. JainAuthor Vitae 《Neurocomputing》2012,76(1):93-104
Community detection in networks is an active area of research with many practical applications. However, most of the early work in this area has focused on partitioning a single network or a bipartite graph into clusters/communities. With the rapid proliferation of online social media, it has become increasingly common for web users to have noticeable presence across multiple web sites. This raises the question whether it is possible to combine information from several networks to improve community detection. In this paper, we present a framework that identifies communities simultaneously across different networks and learns the correspondences between them. The framework is applicable to networks generated from multiple web sites as well as to those derived from heterogeneous nodes of the same web site. It also allows the incorporation of prior information about the potential relationships between the communities in different networks. Extensive experiments have been performed on both synthetic and real-life data sets to evaluate the effectiveness of our framework. Our results show superior performance of simultaneous community detection over three alternative methods, including normalized cut and matrix factorization on a single network or a bipartite graph. 相似文献
30.
对发表于《ISI-SCIE(Science Citation Index Expanded)》上的PHARMACOLOGY&PHARMACY学科的论文作者合作研究形成的一个复杂网络进行了研究。分析表明该合作网络共有40个子网络,其最大连通子网络节点的度服从幂律分布且有厚尾趋势,具有较小的平均路径长度,较大的聚类系数,存在少数关键节点,具有典型的小世界性和无标度性。并通过GN算法分析和挖掘了该最大连通子网络的社团结构,用度值、介数值和PAGERANK值等指标评价了网络的中心节点,揭示了合作网络中合作水平较高的科研团队和具有影响力的科学家。 相似文献