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81.
The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses.  相似文献   
82.
As one of the largest active academic social networking sites, ResearchGate (RG) has been utilized by scholars to share publications, seek collaborators, communicate work in progress, and build scholarly reputation. This study collects data from RG users from 61 U.S. research universities at different research activity levels, as categorized by the Carnegie Classification of Institutions of Higher Education, to examine the impact of institutional differences on RG reputational metrics. The results confirm that RG is a research-oriented academic social networking site that closely and realistically mirrors the research activity level of institutions. With an increase in the research activity level of a university, its affiliated RG users tend to have higher RG scores, more publications and citations, and more profile views and followers, while the average number of reads of their publications and followees tend to be lower and fluctuant. In addition, RG users primarily follow others from institutions of a higher research activity level, forming virtual social networks centered around esteemed institutions. The study suggests academic social networks can serve as indicators in evaluation of research activities among research institutions, and such sites can be helpful and credible for acquiring resources, keeping informed about research, and promoting academic influence.  相似文献   
83.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   
84.
This study explored the co-developmental trajectories of autonomy, competence and relatedness need satisfactions at school and their relations to mental health and academic functioning in Chinese elementary school students. An accelerated longitudinal design was used with a sample of three cohorts (grade 3, grade 4, and grade 5) (N = 1070, 45.8% female; Mage = 9.44, SD = 0.97) on four occasions at 6-month intervals. Parallel process latent class growth models revealed five heterogeneous patterns (i.e., Congruent-moderate; Congruent-high; Congruent-low; Congruent-decreasing; Low-autonomy, High-competence and relatedness), all of which significantly associated with time-varying mental health and academic functioning indicators. The findings highlight the importance of subgroup differences and possible cultural considerations in understanding the progression of psychological need satisfactions and the need for universal screening and dynamic monitoring of students’ psychological need satisfactions at school and implementing more sophisticated interventions tailored to the unique characteristics of the relevant subgroups to promote optimal mental health and learning.  相似文献   
85.
LIU Jing 《海外英语》2014,(10):239-240
Infinitives which consist of bare infinitive and infinitival to are imperative in linguistic studies.And both of the two kinds of infinitives do not indicate person,tense and number.This research aims to analyze the properties,similarities and differences between bare infinitive and infinitival to from the perspective of syntax.Thus,it enables us to attain a uniform characterization of the infinitival to and bare infinitive on the syntactic level and help us to understand these two kinds of infinitives better.  相似文献   
86.
There is evidence that pupils with weak literacy skills struggle on transition to secondary school. Many experience a drop in attainment in the summer break between the two. A British government‐funded programme of rigorously designed research on boosting literacy at transition had (by 2015) found only four of 15 interventions evaluated had positive effects. This small‐scale quasi‐experimental study investigated the effectiveness of support for pupils with mild literacy difficulties on transition to secondary school. Thirty‐two pupils in three schools were involved; half received the programme. Pairs were matched on reading, spelling, age and gender. Intervention was designed around the individual needs of each pupil, focusing variously on language skills, writing, reading and spelling. The group receiving the programme made modest gains in spelling, reading efficiency and single word reading. The comparison group lost ground, relatively, in all three areas. The results suggest a promising line for more rigorous investigation.  相似文献   
87.
晚年的金克木把笔触深入到文化的层面,通过对历史与现今文化的回顾、比较及分析,对我们民族文化的精神进行挖掘与展望。金克木喜欢对历史人物重新进行议论,而他的评价与我们所熟悉的历史定位往往不同,而且有的人物还是我们所不熟悉的,金克木对他们的评价总以一个统一的标准来衡量,那就是文化意义。因为金克木的写作目的很明确,为时下的中国文化乃至世界文化把脉。  相似文献   
88.
我国的社会主义市场经济正处于建立和完善之中,与市场经济相适应的信用体系还没有完全建立起来,各行各业的信用缺失现象较为严重。为此,在分析我国商业企业信用缺失的现状及危害的基础上,进一步剖析了造成我国商业企业信用缺失的原因,并针对具体问题提出了相应的对策措施。  相似文献   
89.
本文运用数理统计法,分析数据中所包含的信息,挖掘出影响普通话水平测试成绩的因素.  相似文献   
90.
“自然无为”是老子哲学思想的显著特色。老子思想中“自然无为”命题并不是无所作为,随心所欲,而是要以辩证法的原则指导人们的社会生活,帮助人们寻找顺应自然、遵循事物客观发展的规律。结合道法自然的生态理念、清静无为的处世哲学、自然纯真的人生旨趣等若干问题,揭示老子“自然无为”这一思想的现代价值。  相似文献   
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