中文团体名称规范标目的选取与著录     

赵宇星  马莉蓉 《图书馆学研究》2008,(7)

团体名称规范是规范工作的重要组成部分,文章从团体名称规范界定范围、标目结构、标目选取原则、各种标目形式和著录方式进行了论述。  相似文献   

基于统计频率的文本分类特征选择算法研究*   总被引：1，自引：0，他引：1  

张俊丽  赵乃瑄  冯君 《现代图书情报技术》2008,24(11):44-48

通过分析χ2统计量（Chi-square, CHI）的缺陷和不足,针对它对低文档频的特征项不可靠,而且不能说明词条和类别的相关性的缺点,对其进行改进,提出统计频率(Statistical Frequency, SF )算法。实验结果表明,统计频率算法能够弥补这些不足,在文本分类中表现出良好的分类效果。  相似文献   

《陈希夷导引坐功图势》考探     

吴志超 《北京体育大学学报》1994,(1)

采用文献法考探了《陈希夷导引坐功图势》的由来;提出它是对前人导引术势的精选、提炼、增删和重构,是医疗导引的一个新分支,既不同于散式导引,又不同于套路式导引;它的形成,标志着医疗导引发展的一个新阶段的开始,由经验领域进入理论领域;它在医疗导引发展中具有承前启后的意义,对养牛和健身都有重大实践意义和理论意义。  相似文献   

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  

张泽梅 《图书馆学研究》2006,(1):53-54,16

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   

Two-stage statistical language models for text database selection   总被引：2，自引：0，他引：2  

Hui Yang  Minjie Zhang 《Information Retrieval》2006,9(1):5-31

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   

我馆几种主要期刊检索途径的调查与分析     

汪倩 《图书馆论坛》2004,24(4):81-83

通过对我校学生读者利用我馆期刊检索途径的调查，分析调查结果，寻找工作中存在的不足，提出改进对策。  相似文献   

基于支持向量机的文本自动分类试验研究     

施洁斌 《现代图书情报技术》2004,20(7):27-29

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   

Setting the Students’ Bearings and Balance in Appraisal     

Barbara L. Craig 《Archival Science》2005,5(2-4):391-402

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   

Co-occurrence of adverse childhood experiences and its association with family characteristics. A latent class analysis with Dutch population data     

《Child abuse & neglect》2019

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   

长江口深水航道船舶超宽交会通航效率分析     

周伟  肖英杰  郑剑 《上海海事大学学报》2019,40(2):1-5

为提高长江口深水航道通过能力,减少由船舶交会宽度限制产生的延误,通过分析船舶超宽交会现状,建立仿真逻辑模型,运用Arena进行离散仿真试验。采集长江口深水航道交通流数据,设置不同的船舶交会宽度限制,对大型船舶进出港过程进行仿真,分析不同交会宽度限制对船舶通航的影响,获得被延误船舶比例、被延误船舶数量和延误时间,进而提出提升通过能力的建议。试验表明,采用Arena进行离散仿真能够量化分析超宽交会对通航效率的影响,可为航道拓宽和交通管理提供科学依据。  相似文献