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Twelve Chinese academic journals, indexed by SCI and financed by the National Natural Science Foundation (NNSF), were analysed using the 2000–2003 Total Citations and Impact Factor data from JCR. It is concluded that the quality of Chinese journals is generally low and has remained so despite recent government measures aimed at improvement. Several factors are influential – particularly the Chinese government's policy of encouraging submission to foreign journals. Finance, management, and the academic degree policy are also obstacles. It is suggested that the Chinese government should reconsider its current policies so as to encourage higher quality in domestic periodicals and thus a greater recognition of Chinese journals by the international academic community. 相似文献
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Jennifer R. Warren Michael L. Hecht David A. Wagstaff Elvira Elek Khadidiatou Ndiaye Patricia Dustman Flavio F. Marsiglia 《Journal of Applied Communication Research》2006,34(2):209-227
This study sought to determine if exposure to two communication-oriented activities, videotapes and public service announcements, accounts for changes in substance use among adolescents participating in the Drug Resistance Strategies Project's keepin' it REAL adolescent substance use prevention curriculum. Middle-school students (4,734, 72% Latino) responded to questionnaires related to these analyses. An analysis of covariance (ANCOVA) model was fit separately to six substance use outcomes. The results suggested that intervention students who saw four or five videos engaged in less substance use in the past month than did students who saw fewer videos. Having seen the PSAs one or more times did not predict the reported change in substance use. 相似文献
76.
Tuomo Korenius Jorma Laurikkala Martti Juhola Kalervo Järvelin 《Information Retrieval》2006,9(1):33-53
Search facilitated with agglomerative hierarchical clustering methods was studied in a collection of Finnish newspaper articles
(N = 53,893). To allow quick experiments, clustering was applied to a sample (N = 5,000) that was reduced with principal components analysis. The dendrograms were heuristically cut to find an optimal partition,
whose clusters were compared with each of the 30 queries to retrieve the best-matching cluster. The four-level relevance assessment
was collapsed into a binary one by (A) considering all the relevant and (B) only the highly relevant documents relevant, respectively.
Single linkage (SL) was the worst method. It created many tiny clusters, and, consequently, searches enabled with it had high
precision and low recall. The complete linkage (CL), average linkage (AL), and Ward's methods (WM) returned reasonably-sized
clusters typically of 18–32 documents. Their recall (A: 27–52%, B: 50–82%) and precision (A: 83–90%, B: 18–21%) was higher
than and comparable to those of the SL clusters, respectively. The AL and WM clustering had 1–8% better effectiveness than
nearest neighbor searching (NN), and SL and CL were 1–9% less efficient that NN. However, the differences were statistically
insignificant. When evaluated with the liberal assessment A, the results suggest that the AL and WM clustering offer better
retrieval ability than NN. Assessment B renders the AL and WM clustering better than NN, when recall is considered more important
than precision. The results imply that collections in the highly inflectional and agglutinative languages, such as Finnish,
may be clustered as the collections in English, provided that documents are appropriately preprocessed. 相似文献
77.
Creating Access to Invisible Special Collections: Using Participatory Management to Reduce a Backlog
The University of Colorado at Boulder Libraries used participatory management to reduce a special collections backlog. Without an increase in budget or staffing, technical and public services departments designed a pilot project to redeploy internal human resources in a collaborative manner. The process of backlog management is discussed. 相似文献
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Subjective Social Location: Data From 21 Nations 总被引:1,自引:0,他引:1
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Techtarget Todd R. Weiss 《信息系统工程》2005,(3):16
keystone公司长期停滞的ERP项目终于宣告成功, 系统将 130 个厂房,全美国2000 多员工连接在一起。回首keystone 信息化历程,其经验教训值得我们深思。 相似文献