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51.
《Journal of Informetrics》2014,8(2):369-383
Subject classification arises as an important topic for bibliometrics and scientometrics, searching to develop reliable and consistent tools and outputs. Such objectives also call for a well delimited underlying subject classification scheme that adequately reflects scientific fields. Within the broad ensemble of classification techniques, clustering analysis is one of the most successful.Two clustering algorithms based on modularity – the VOS and Louvain methods – are presented here for the purpose of updating and optimizing the journal classification of the SCImago Journal & Country Rank (SJR) platform. We used network analysis and Pajek visualization software to run both algorithms on a network of more than 18,000 SJR journals combining three citation-based measures of direct citation, co-citation and bibliographic coupling. The set of clusters obtained was termed through category labels assigned to SJR journals and significant words from journal titles.Despite the fact that both algorithms exhibited slight differences in performance, the results show a similar behaviour in grouping journals. Consequently, they are deemed to be appropriate solutions for classification purposes. The two newly generated algorithm-based classifications were compared to other bibliometric classification systems, including the original SJR and WoS Subject Categories, in order to validate their consistency, adequacy and accuracy. In addition to some noteworthy differences, we found a certain coherence and homogeneity among the four classification systems analysed. 相似文献
52.
全国计算机等级考试(NCRE)对高校非计算机专业的复合型人才培养,起到了积极推动作用,鼓励高校学生参加NCRE考试是适宜的,在计算机基础教学中可以适当参考NCRE考试大纲。不断探索NCRE试题库建设,完善考试科目和等级设置等,是NCRE进一步适应社会对复合型人才需求的重要举措。 相似文献
53.
Kathleen M Shannon 《Teaching Statistics》1999,21(2):42-45
Issues of measurement are fundamental in statistics but often overlooked in introductory courses. This interactive exercise encourages students to think critically about how things are measured. 相似文献
54.
元素进出栈问题是计算机等级考试中常见的问题。元素进出栈类似于蚂蚁进出洞,故而,本文一开始是在叙述一个小故事,接着引入元素进出栈问题。本文最终解决的问题是,任意n个元素进栈并出栈排序后,会有多少种不同的排列。 相似文献
55.
随着计算机网络技术的发展,基于Web的计算机等级考试报名系统正在逐步取代传统的报名模式。为此我们研究采用B/S结构来代替C/S结构,并结合Linux开源系统、PHP语言和MySql数据库来搭建一套基于Web的全国计算机等级考试服务与支持系统,实现数据库、应用系统实时的和集中式的管理,以便考试管理部门能够实时掌握和监管报名过程。同时,本文将引入严格的安全管理机制,以保证数据的安全性。 相似文献
56.
利用Kendall协合系数检验来判断学校综合评分成绩计算公式中所选用的评分指标是否合理，并给出各评分指标权重的计算方法，为学校教学的科学管理提供重要依据。 相似文献
57.
采用不确定型层次分析法对栈道现状进行评估,建立栈道递阶层次模型,对栈道指标权重采用最优传递矩阵法进行计算,在采用最大隶属度邻近判别法对栈道进行最终的等级评估之前,应先对评语指标采用等级隶属度函数进行模糊化处理。结果表明,不确定型层次分析法能够全面考虑影响栈道安全性的各种因素,而且,最优传递矩阵法计算权重精度高,使得栈道安全评估结果更加可靠。 相似文献
58.
In this paper we measure the effect of Internet adoption on consumers’ propensity to adopt a wide range of diffusing products. To do this, we utilize a rich panel of household surveys on purchases of relatively new technology products. Our results indicate that the Internet accelerates product diffusion, but with varying magnitude. In an attempt to determine the mechanisms underlying this effect, we find direct evidence that the Internet does not increase product awareness. However, we find suggestive evidence that the Internet increases adoption rates both through access to increased information about new products (via online research) and through online shopping. We also find that the magnitude of the Internet's effect is strongly tied to diffusion rates, and especially familiarity rates. This finding is consistent with Internet access having the greatest impact on the adoption of products with more developed marketing strategies (i.e., more developed information sources and online markets). Our findings indicate that the Internet helps bolster demand for products early in their diffusion process, and they suggest that improved access to information and the convenience of online shopping are likely the primary drivers of this effect. Consequently, to the extent that accelerated diffusion of new products is (on net) desirable, our findings may provide a further argument toward social promotion of Internet adoption. 相似文献
59.
武术段位制纳入高校的改革对策 总被引：1，自引：0，他引：1
文章采用文献资料研究方法,通过对武术段位制的技术考评体系和理论考评体系的分析,探讨了武术段位制在高校的实施办法,为促进武术运动在高校的进一步开展提供参考,为弘扬民族传统文化奠定基础。 相似文献
60.
The aim of this study was to determine whether different areas of knowledge presented different behaviour with regard to the number of references cited per journal document or if, conversely, they shared the same reference density practices. Bibliometric and bibliographic data were collected from 27,141 journals (indexed between 2001 and 2015 in the SCImago Journal & Country Rank (SJR)) and the growth rates in reference density and number of documents and journals in each category were calculated at different levels of aggregation.Our analysis identified that (a) mean reference density values in some Social Sciences and Arts and Humanities categories were equal to or higher than those in the “hard sciences”; (b) reference density growth rates in these disciplines were not as high as those in the hard sciences and, in general, did not correspond with growth rates in the number of documents produced; (c) this can be considered an indication that citation-based evaluation practices affect publication habits; and (d) no significant differences were found in mean values or growth rates between Gold Open Access and Non Gold Open Access journals. 相似文献