首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3869篇
  免费   61篇
  国内免费   79篇
教育   2742篇
科学研究   440篇
各国文化   3篇
体育   367篇
综合类   282篇
文化理论   1篇
信息传播   174篇
  2024年   1篇
  2023年   5篇
  2022年   24篇
  2021年   37篇
  2020年   62篇
  2019年   46篇
  2018年   40篇
  2017年   48篇
  2016年   50篇
  2015年   90篇
  2014年   242篇
  2013年   247篇
  2012年   309篇
  2011年   342篇
  2010年   235篇
  2009年   219篇
  2008年   272篇
  2007年   312篇
  2006年   289篇
  2005年   267篇
  2004年   242篇
  2003年   204篇
  2002年   161篇
  2001年   98篇
  2000年   74篇
  1999年   30篇
  1998年   15篇
  1997年   6篇
  1996年   10篇
  1995年   2篇
  1994年   9篇
  1993年   4篇
  1992年   1篇
  1991年   2篇
  1989年   2篇
  1988年   3篇
  1987年   3篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1957年   1篇
排序方式: 共有4009条查询结果,搜索用时 15 毫秒
1.
目前在文献中有很多关于多响应比较的研究方法,但是对带协变量调整的非参数检验的研究较少。一种直观的想法是将数据先投影到协变量的正交空间中,然后再利用秩和检验、调整的秩和检验或最大值检验方法。但是,功效普遍不高。在调整的秩和检验和伪F检验两种方法基础上,构建MIN2检验。大量模拟和实际数据表明,MIN2检验的效果优于现有的非参数检验方法。  相似文献   
2.
[目的/意义]为了深入了解科研众筹平台中的项目情况,本文对科研众筹项目的基本特征、研究主题和不同类型科研众筹项目的属性对比进行研究。[研究设计/方法]首先对科研众筹的起源、价值和运作模式进行了梳理;随后爬取了科研众筹平台Experiment的项目信息,并对该平台中科研项目的发起者、背书者、项目记录、所属学科、资助情况等进行特征描述;基于LDA模型对科研众筹项目主题进一步细化,并对不同资金筹集和不同主题分类情况下的科研众筹项目的属性差异进行比较分析。[结论/发现]科研众筹主题主要集中在生物学和生态学两个领域,不同资金筹集达成情况的科研众筹项目在项目背书者数量、信息记录次数和讨论次数上具有显著差异;不同主题的科研众筹项目在其讨论次数上具有显著差异。同时,是否提供视频和是否参与资助挑战在不同资金筹集达成情况和不同主题的科研众筹项目上均具有显著差异。[创新/价值]深入分析了科研众筹平台中项目主题及属性对比情况,对科研众筹平台优化信息审核机制、社交机制和信息展示机制具有一定的参考价值。  相似文献   
3.
Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA.  相似文献   
4.
运用双框架模型对中美竞技体育国际竞争力进行比较研究。认为:①从显现性框架分析,美国竞技体育国际竞争力一直稳定处于高位,而中国则呈现以2008年为峰顶的倒“U”型发展特征,且与美国还存在一定差距;②从解释性框架分析,美国竞技体育国际竞争力已趋于顶峰,而中国稳步提升;③中国竞技体育发展潜力巨大,但短时间内难以赶超美国;④“举国体制”有利于中国竞技体育显现性竞争力的提升,但与美国社会办竞技体育的发展模式相比,市场、社会在竞技体育发展中的作用发挥不足,不利于高经济性项目、高欣赏性项目的发展;⑤坚持“举国体制”、承办2022年冬奥会有利于中国竞技体育显现性竞争力的提升和冬季项目的发展,但同样存在竞技体育项目布局转型的困难和群众体育基础薄弱的困境。  相似文献   
5.
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback.  相似文献   
6.
通过“心与心的交流和方法与方式的优化”两个方面来阐述如何轻松、愉快、有效、合理地提高小学数学学困生的教学质量。  相似文献   
7.
We use five waves of the Indonesian Family Life Survey (IFLS) to create unique father-son matched data of the male population (aged 25–53). Using this data, we investigate the evolution of intergenerational transmission of educational attainment in Indonesia over time, by ethnicities (six major ethnic groups), and by regions (twelve provinces). To estimate the persistence in education (measured as schooling years of the father as a predictor of schooling years of the son), we use coefficient of correlation and regression coefficient methods. Our results from the regression coefficient suggest that persistence in Indonesia is declined over time. Whereas, the results from the coefficient of correlation reveals no secular trend in education persistence over time. Thus, to understand the reason behind the secular trend in the correlation coefficient we decompose the correlation following Checchi and García-Peñalosa (2008). The decomposed intergenerational correlation shows that although the persistence is declined at the lower-end of fathers’ education distribution, it is increased at the top-end of the distribution. Therefore, we argue that the coefficient of correlation should be used with caution while analyzing the education policy particularly the persistence in education. Thereafter, we document the stationary distribution and find the conclusive evidence of non-convergence in educational attainment over time among both, ethnicities and regions.  相似文献   
8.
Children in kindergarten were randomly assigned to adaptive computerised counting or comparison interventions, or to a business-as-usual control group. Children in both intervention groups, including children with poor calculation skills at the start of the intervention, performed better than controls in the posttest. However the effects of training held in grade 1, playing serious counting games improving number knowledge and mental arithmetic performances, and playing serious comparison games, only enhanced the number knowledge proficiency in grade 1. The value of these short periods of intensive gaming in kindergarten are discussed as a look-ahead approach to enhance arithmetic proficiency.  相似文献   
9.
中英两种语言都有其独特的亲属称谓体系。本文通过对父系与母系、姻亲和血亲、长幼关系以及泛化的中英亲属称谓差异的比较,探询其背后的文化因素,发现家庭类型、宗法观念、继嗣制、宗教信仰、价值取向、社会性质和政治生活等是造成两者差异的主要原因。通过探究,使我们更好地了解中西方文化,从而减少跨文化交际中所产生的困惑和误解,使跨文化交际顺利进行。  相似文献   
10.
only lies in its deep theme and striking arrangement of events,but also in her accurate and vivid language.In order to study the differences between English and Chinese,This thesis is focused on two Chinese versions of Whuthering Heights in the light of contrastive linguistics.The detailed version comparison consists of two parts: the comparison between two Chinese versions in lexicology and syntax.After comparing two versions,the author noted that both Yang and Lu still commit some mistakes because of ignorance of linguistic and cultural differences between English and Chinese and in view of this mistakes,the paper offers some revised translation texts for reference only.The author hopes that the comparison results may be beneficial to cross-culture communication and English learning.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号