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201.
网络数据挖掘及其在面向Web的知识检索中的应用 总被引:6,自引:1,他引:5
介绍了网络数据挖掘的含义和相关技术,并着重介绍了网络数据挖掘方法在面向Web的知识检索中的应用:通过对信息源内容与结构的挖掘,对用户访问记录的挖掘,对专家访问的挖掘,发现隐藏在网络数据流背后的知识关联和知识,形成特定知识库,支持知识检索。 相似文献
202.
图书馆实践与理论研究的新创获——《知识信息管理》评介 总被引:4,自引:0,他引:4
即将出版的《知识信息管理》一书 ,对世纪之交图书馆工作的本质属性和时代特征进行了深入研究 ,认为 2 1世纪图书馆工作就是知识信息资源管理。该书观点新颖 ,体系完备 ,论述科学 ,文风严谨。 相似文献
203.
理想的网络信息组织模式应该以用户为中心 ,遵循实用性和易用性原则 ,综合运用自然语言和人工语言 ,充分利用新兴技术和人们经验的积累 ,朝着信息描述标准化、组织活动合作化、组织技术智能化、资源与服务集成化、用户界面可视化、内容揭示深入化、组织方法多样化方向发展。图 1。参考文献 30。 相似文献
204.
图书馆知识服务的思考 总被引:13,自引:0,他引:13
文章提出了知识服务的本质是利用“知识”服务,还是提供“知识”产品的问题。并通过分析给出了自己的答案。认为知识服务就是以知识为基础的服务,推进知识服务的过程就是增加图书馆服务的知识含量的过程。并指出了图书馆增加服务知识含量的两个发展方向。 相似文献
205.
206.
For at least a decade, U.S. funding agencies and university campuses have promoted the expansion of interdisciplinary research. At the same time, federal and local programs have sought to increase the participation of women and minorities in science, mathematics, and engineering. Research has focused on each of these trends independently, but very few studies have considered their interaction by asking how intellectual preferences for and professional consequences of interdisciplinary science might be influenced by gender, race, and/or ethnicity. Focused specifically on gender, this paper considers the expectation that women will be more drawn to interdisciplinary research, and explores the learning styles, work preferences, and career behaviors that might anticipate and/or explicate gender differences in interdisciplinary science. Principal mechanisms by which researchers engage in interdisciplinarity - cross-fertilization, team-collaboration, field-creation, and problem-orientation - are tested for evidence of gendering using preliminary empirical data from three studies. The results of this exploratory analysis offer clues about possible tendencies and raise questions about the potential costs and benefits for those who adopt them. 相似文献
207.
208.
Combining entrepreneurial and scientific performance in academia: towards a compounded and reciprocal Matthew-effect? 总被引:2,自引:0,他引:2
The increase of entrepreneurial activity within academia has raised concerns that the research orientation of universities might become ‘contaminated’ by the application-oriented needs of industry. Empirical evidence on this concern is scarce and ambiguous. We examine whether entrepreneurial and scientific performance in academia can be reconciled. Our empirical findings (KU Leuven, Belgium) suggest that both activities do not hamper each other; engagement in entrepreneurial activities coincides with increased publication outputs, without affecting the nature of the publications involved. As resources increase, this interaction becomes more significant, pointing towards a Matthew-effect. We finally suggest that balancing both activities further depends on the institutional policies deployed. 相似文献
209.
Current citation-based document retrieval systems generally offer only limited search facilities, such as author search. In order to facilitate more advanced search functions, we have developed a significantly improved system that employs two novel techniques: Context-based Cluster Analysis (CCA) and Context-based Ontology Generation frAmework (COGA). CCA aims to extract relevant information from clusters originally obtained from disparate clustering methods by building relationships between them. The built relationships are then represented as formal context using the Formal Concept Analysis (FCA) technique. COGA aims to generate ontology from clusters relationship built by CCA. By combining these two techniques, we are able to perform ontology learning from a citation database using clustering results. We have implemented the improved system and have demonstrated its use for finding research domain expertise. We have also conducted performance evaluation on the system and the results are encouraging. 相似文献
210.
We explore a financial returns dimension of the exploration-exploitation dilemma. Using 1277 R&D announcements by 178 listed bio-pharmaceutical firms, we examine whether investors are myopic along the continuum of exploration (patenting and preclinical trials) to exploitation (human clinical trials and NDA). We find that investors respond positively at every stage, but there are differences between small and large firms. For small firms exploration is favored, provided it is focused. For large firms, there is value in both exploration and exploitation. Projects which are part of an alliance are no more likely to generate abnormal returns. Policy implications are discussed. 相似文献