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21.
国内高校图书馆管理集成系统的选择   总被引:6,自引:0,他引:6  
本文在对我国高等学校图书馆管理集成系统使用情况分析的基础上,简要介绍了几种拥有用户较多的文献信息管理系统,并据此提出高校图书馆在选择文献信息管理系统时应注重的标准、原则,指出高校图书馆管理集成系统的发展趋势。  相似文献   
22.
本文从话语理论这一视角出发,考察新闻源对新闻话语的生成所产生的影响,认为在许多情况下,记者虽然是新闻话语的写作者,但他并非是话语的主体,他只不过是充当了编码者和代言者的角色,权威的新闻源才真正是新闻话语中说话的人。  相似文献   
23.
Two-stage statistical language models for text database selection   总被引:2,自引:0,他引:2  
As the number and diversity of distributed Web databases on the Internet exponentially increase, it is difficult for user to know which databases are appropriate to search. Given database language models that describe the content of each database, database selection services can provide assistance in locating databases relevant to the information needs of users. In this paper, we propose a database selection approach based on statistical language modeling. The basic idea behind the approach is that, for databases that are categorized into a topic hierarchy, individual language models are estimated at different search stages, and then the databases are ranked by the similarity to the query according to the estimated language model. Two-stage smoothed language models are presented to circumvent inaccuracy due to word sparseness. Experimental results demonstrate that such a language modeling approach is competitive with current state-of-the-art database selection approaches.  相似文献   
24.
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   
25.
提出了将支持向量机应用于文本自动分类的研究,与常用的K-最邻近法相比,无论是对训练数据集还是测试数据集均具有一定的优势,而且不同特征选择方法对支持向量机的影响要比K-最邻近法小。此外,从研究中的不同特征选择的评价函数来看,它们对分类有一定的影响,应用X2统计进行特征选择的分类正确率最高,其次是文本证据权,而期望交叉熵的效果最差,说明特征选择在文本自动分类中也是相当重要的。  相似文献   
26.
The author, a professor at the University of Toronto, touches briefly on the extensive and rich archival literature that supports the teaching of macroappraisal, but notes that this is not the only educational material she offers her students when teaching appraisal theory. She discusses the usefulness to archivists of literature from the fields of ethnography, organizational knowing, records in history, personal documentary behaviour, memory, and communications, noting that the use of texts from these fields can encourage students to reflect on their own presumptions and to develop a taste for the wide reading and research that must support appraisal.  相似文献   
27.
从四个方面阐述了“两课”教学中存在的普遍问题,并从提高教师素质、改进教学方法、领导重视三方面提出了创新“两课”教学,发挥其在高校思想政治教育中主渠道和主阵地作用的方法。  相似文献   
28.
BackgroundAlthough adverse childhood experiences (ACEs) are relatively common among children, there is limited knowledge on the co-occurrence of such experiences.ObjectiveThe current study therefore investigates co-occurrence of childhood adversity in the Netherlands and whether specific clusters are more common among certain types of families.Participants and SettingRepresentative data from the Family Survey Dutch population 2018 (N = 3,128) are employed.MethodWe estimate Latent Class Analysis (LCA) models to investigate co-occurrence of ACEs. As ACEs we examine maltreatment, household dysfunction, demographic family events, as well as financial and chronic health problems. Gradual measures for maltreatment and financial problems are studied to make it possible to differentiate with regard to the severity of experiences.ResultsOur results show that four ACE clusters may be identified: ‘Low ACE’, ‘Moderate ACE: Household dysfunction’, ‘Moderate ACE: Maltreatment’ and ‘High ACE’. Regression analyses indicated that mother’s age at first childbirth and the number of siblings were related to experiencing childhood adversity. We found limited evidence for ACEs to be related to a family’s socioeconomic position.ConclusionThe found clusters of ACEs reflect severity of childhood adversity, but also the types of adversity a child experienced. For screening and prevention of childhood adversity as well as research on its consequences, it is relevant to acknowledge this co-occurrence of types and severity of adversity.  相似文献   
29.
Education researchers, policymakers, and practitioners are concerned with identifying and developing talent for students with fewer opportunities, especially students from historically marginalized groups. An emerging body of research suggests “universally screening” or testing all students, then matching those students with appropriate educational challenges, is effective in helping marginalized students. However, most tests have focused on two areas: math and verbal reasoning. We leverage three nationally representative samples of the U.S. population at different time points that include both novel cognitive measures (e.g., spatial, mechanical, and abstract reasoning) and non-cognitive measures (e.g., conscientiousness, creativity or word fluency, leadership skill, and artistic skill) to uncover which measures would improve proportional representation of marginalized groups in talent identification procedures. We find that adding spatial reasoning measures in particular—as well as other non-cognitive measures such as conscientiousness, leadership, and creativity—are worthwhile to consider for universal screening procedures for students to narrow achievement gaps at every level of education, including for gifted students. By showing that these nontraditional measures both improve proportional representation of underrepresented groups and have reasonable predictive validity, we also broaden the definition of what it means to be “gifted” and expand opportunities for students from historically marginalized groups.  相似文献   
30.
对河南省大学生体育课项目选择和影响因素进行了调查研究 ,发现大学生的体育学习和体育课项目选择有不同特点 .文章分析了形成目前状况的原因 ,这对我们安排教学内容 ,培养授课教师 ,提高大学生上体育课的兴趣 ,形成他们良好的锻炼习惯 ,增强体质都有重要的作用 .  相似文献   
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