主题图技术与相关知识组织方法的比较研究   总被引：6，自引：0，他引：6  

马建霞 《图书馆杂志》2007,26(2):47-53

通过简单介绍主题图的定义及其核心概念,与相关的知识组织方法,如索引、词汇表、叙词表、分类法、概念图,以及语义网中的知识表现等进行了比较。  相似文献   

信息时代的"全球定位系统"--主题地图   总被引：16，自引：0，他引：16  

秦铁辉  郭延吉  孙琳 《江西图书馆学刊》2005,35(1):1-3,7

作为一项新的ISO标准(ISO／IEC 13250),主题地图(Topic Maps)被称为“信息时代的全球定位系统”,也是知识管理的一种实现技术。尽管主题地图能够表示复杂的知识结构,但是它的基本概念——主题、联系和事件(TAO)还是很容易掌握的。简单介绍了主题地图的概念及其背景,详细阐释其基本构成,并将它与我们熟悉的信息管理联系起来,还描述了主题地图未来的一些可能应用。  相似文献   

一个Bocs的表示范畴—M(x)=J_1;mJq;m的情形     

武月琴 《雁北师范学院学报》2000,(6)

该文证明了对于一般的 M∈ R(Γ ) ,M( x) =J1;m Jq;m在 R(Γ )中存在始于 (终于 ) M的左 (右 )几乎可裂序列  相似文献   

开（闭）映射的点态特征     

周淑云 《青海师专学报》2000,20(3):12-13

本文用点态来定义开（闭）映射,并应用此定义来证明开（闭）映射的一些性质。  相似文献   

How Can Released State Test Items Support Interim Assessment Purposes in an Educational Crisis?     

Emma M. Klugman  Andrew D. Ho 《Educational Measurement》2020,39(3):65-69

State testing programs regularly release previously administered test items to the public. We provide an open-source recipe for state, district, and school assessment coordinators to combine these items flexibly to produce scores linked to established state score scales. These would enable estimation of student score distributions and achievement levels. We discuss how educators can use resulting scores to estimate achievement distributions at the classroom and school level. We emphasize that any use of such tests should be tertiary, with no stakes for students, educators, and schools, particularly in the context of a crisis like the COVID-19 pandemic. These tests and their results should also be lower in priority than assessments of physical, mental, and social–emotional health, and lower in priority than classroom and district assessments that may already be in place. We encourage state testing programs to release all the ingredients for this recipe to support low-stakes, aggregate-level assessments. This is particularly urgent during a crisis where scores may be declining and gaps increasing at unknown rates.  相似文献   

数据驱动下的高校图书馆课程地图构建     

张彤阳  杨况骏瑜  侯壮  蒋楠 《图书馆论坛》2020,(6):100-109

文章探索数据驱动下高校图书馆课程地图构建的变革及实现:建立图书馆多维数据与课程地图各核心要素之间的逻辑关系,利用数据库技术、文献计量法、问卷调查等方式收集数据,综合运用统计学原理、词频分析工具、比较分析方法、学习热度公式来分析数据,以更贴近学生需求的方式生成课程计划,构建基于多维数据的课程地图。实践结果显示:文章提出的课程地图构建新路径简单清晰、易于分享和推广、具有可用性和可扩展性,可为课程地图的构建提供新的思路--由"以经验描述为主要依据和以静态标准为单一导向"转向"基于数据全面分析"。  相似文献   

Exploring coherent topics by topic modeling with term weighting     

Ximing Li  Ang Zhang  Changchun Li  Jihong Ouyang  Yi Cai 《Information processing & management》2018,54(6):1345-1358

Topic models often produce unexplainable topics that are filled with noisy words. The reason is that words in topic modeling have equal weights. High frequency words dominate the top topic word lists, but most of them are meaningless words, e.g., domain-specific stopwords. To address this issue, in this paper we aim to investigate how to weight words, and then develop a straightforward but effective term weighting scheme, namely entropy weighting (EW). The proposed EW scheme is based on conditional entropy measured by word co-occurrences. Compared with existing term weighting schemes, the highlight of EW is that it can automatically reward informative words. For more robust word weight, we further suggest a combination form of EW (CEW) with two existing weighting schemes. Basically, our CEW assigns meaningless words lower weights and informative words higher weights, leading to more coherent topics during topic modeling inference. We apply CEW to Dirichlet multinomial mixture and latent Dirichlet allocation, and evaluate it by topic quality, document clustering and classification tasks on 8 real world data sets. Experimental results show that weighting words can effectively improve the topic modeling performance over both short texts and normal long texts. More importantly, the proposed CEW significantly outperforms the existing term weighting schemes, since it further considers which words are informative.  相似文献   

What is the effect of country-specific characteristics on the research performance of scientific institutions? Using multi-level statistical models to rank and map universities and research-focused institutions worldwide     

《Journal of Informetrics》2014,8(3):581-593

Bornmann, Stefaner, de Moya Anegón, and Mutz (2014) have introduced a web application (www.excellencemapping.net) which is linked to both academic ranking lists published hitherto (e.g. the Academic Ranking of World Universities) as well as spatial visualization approaches. The web application visualizes institutional performance within specific subject areas as ranking lists and on custom tile-based maps. The new, substantially enhanced version of the web application and the generalized linear mixed model for binomial data on which it is based are described in this paper. Scopus data are used which have been collected for the SCImago Institutions Ranking. Only those universities and research-focused institutions are considered that have published at least 500 articles, reviews and conference papers in the period 2006–2010 in a certain Scopus subject area. In the enhanced version, the effect of single covariates (such as the per capita GDP of a country in which an institution is located) on two performance metrics (best paper rate and best journal rate) is examined and visualized. A covariate-adjusted ranking and mapping of the institutions is produced in which the single covariates are held constant. The results on the performance of institutions can then be interpreted as if the institutions all had the same value (reference point) for the covariate in question. For example, those institutions can be identified worldwide showing a very good performance despite a bad financial situation in the corresponding country.  相似文献   

局部强序列连通空间     

郑春燕 《莆田学院学报》2014,(2):1-4,41

讨论了保聚映射的一些性质,证明了保聚映射保持强序列连通性;并定义了局部强序列连通空间,证明了商映射保持局部强序列连通空间以及局部强序列连通性具有开遗传性和有限可积性;还给出了一些相关的刻画及其性质。  相似文献   

Y上连续的连通集值映射的周期轨道     

付林林  张更容 《广西梧州师范高等专科学校学报》2014,(1):123-129

文章定义了Y空间上连续的连通集值映射及其周期轨道,探索了Y空间上连续的连通集值映射与y上的连续自映射之间的关系,得到了关于Y上连续的连通集值映射的两个定理。  相似文献