Does modality matter? A latent profile and transition analysis of sedentary behaviours among school-aged youth: The UP&DOWN study

ABSTRACT

The aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time.     

网络环境下的主题标引工作

探讨了网络环境下编目人员应如何充分利用计算机编目的特点及网络优势来做好主题标引工作，满足读检索的需要，具体做法是：转变编目思想，降低检索难度，提高标引深度，主题标引要一致。     

A Corpus-Based Learning Method of Compound Noun Indexing Rules for Korean

In Korean information retrieval, compound nouns play an important role in improving precision in search experiments. There are two major approaches to compound noun indexing in Korean: statistical and linguistic. Each method, however, has its own shortcomings, such as limitations when indexing diverse types of compound nouns, over-generation of compound nouns, and data sparseness in training. In this paper, we propose a corpus-based learning method, which can index diverse types of compound nouns using rules automatically extracted from a large corpus. The automatic learning method is more portable and requires less human effort, although it exhibits a performance level similar to the manual-linguistic approach. We also present a new filtering method to solve the problems of compound noun over-generation and data sparseness.     

全国中文机读书目主题标引格式问题分析

中文机读书目主题标引格式的不统一 ,会产生书目主题格式多样的弊端。其主要原因是由于叙词法后组式标题只能套录标题法先组式标题格式。因此 ,必须统一中文书目主题标引格式。表 2。参考文献 8。     

公安类考生体能测试考前心理状况的调整

运用问卷、文献资料和调查访问等研究方法，对浙江省近两年来公安类考生的考前心理状态进行了分析研究，结果表明，有针对性地从意识和行为上加强应考前心理状态的调整对发挥考生潜能，取得优异成绩有重要意义，针对考生的不利心理状态，提出了消除的方法。     

VISION:集成分类法、主题词表和语义元数据的概念网络

本文提出了一种在分类法和主题词表的基础上集成语义元数据、构建概念网络、实现概念检索的方法.和其他的概念检索系统相比,它的最大特色是在检索之前先将信息资源根据其内容和主题组织到概念网络中.这样的概念网络,既是一个资源组织的框架,又是一个知识浏览和概念检索的信息空间.同时,还能支持用户学习.文章介绍了国内外概念检索的研究现状,讨论了集成分类法、主题词表和语义元数据构建概念网络的方法和好处.介绍了一个原型系统VISION,它是在<中国分类主题词表>的基础上,利用北京大学图书馆计算机类的书目数据实现的.文章最后进行深入讨论并介绍下一步的研究工作.     

现代汉语N+V状中短语的句法功能与语义指向分析

现代汉语中,名词能够与动词组合构成N+V状中短语,其性质是动词性的,在句中能作谓语、定语、主语和宾语。N+V状中短语在作谓语时,其中的名词性状语N从语义指向上看,有时指向谓语动词V,有时指向结构中的其他名词性成分。     

中文书目数据常见问题分析

本文在多年编目工作实践与研究的基础上，总结了目前各编目机构制作的中文机读书目数据中经常出现的著录、主题标引、分类标引方面的质量问题，并对此作了一定的分析。     

外来词产生及流行的修辞学理据

外来词属于词汇学的范畴。外来词通过潜词显化、显意符号化、显词重叠化三种途径产生，其中的显词重叠化造成了外来词与汉语词的同义关系，而外来词独特的修辞效果也使人们在同义手段选择活动中更青睐于外来词。     

谈谈如何处理文革资料

文革资料不同于普通报刊资料,具有-定的特殊性.只有做好它的研究工作,才能为建立文革资料数据库打下良好的基础.