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1.
Although Affirmative Action policies have been enforced in many countries, their consequences are highly understudied, especially in the context of developing economies. Section 12(1)(c) of the Right to Education (RTE) Act enforced in 2009 is the first attempt to introduce affirmative action in primary schools in India. The act requires all private schools to reserve at least twenty five percent seats for children from economically weaker sections. To understand the effect of the act on i) social integration and ii) academic outcomes, we asked 1500 children (grades one to three) from four schools to answer friendship surveys and short tests in Mathematics and English. The schools in our sample vary considerably in constitution and were intentionally chosen to understand the impact of the act in different school settings. The friendship surveys show strong homophily i.e. non-RTE students cite other non-RTE students as friends, while RTE students chose to be friends primarily with other RTE students. Trends in test scores reveal that students admitted under the RTE quota score significantly lower than non-RTE students. However, RTE students who have a higher share of non-RTE friends have better test scores, suggesting that affirmative action may have a positive influence on learning outcomes for RTE children. Further we note that commitment from the school authorities and systematic monitoring and evaluation of the implementation of the act will go a long way in bringing out some of the benefits that this act was designed to achieve. Our findings have important policy implications with respect to ensuring proper implementation of the Section12(1)(c) of the RTE act in schools across the country. 相似文献
2.
In this digital ITEMS module, Dr. Jeffrey Harring and Ms. Tessa Johnson introduce the linear mixed effects (LME) model as a flexible general framework for simultaneously modeling continuous repeated measures data with a scientifically defensible function that adequately summarizes both individual change as well as the average response. The module begins with a nontechnical overview of longitudinal data analyses drawing distinctions with cross-sectional analyses in terms of research questions to be addressed. Nuances of longitudinal designs, timing of measurements, and the real possibility of missing data are then discussed. The three interconnected components of the LME model—(1) a model for individual and mean response profiles, (2) a model to characterize the covariation among the time-specific residuals, and (3) a set of models that summarize the extent that individual coefficients vary—are discussed in the context of the set of activities comprising an analysis. Finally, they demonstrate how to estimate the linear mixed effects model within an open-source environment (R). The digital module contains sample R code, diagnostic quiz questions, hands-on activities in R, curated resources, and a glossary. 相似文献
3.
This study employed fixed effects regression that controls for selection bias, omitted variables bias, and all time-invariant aspects of parent and child characteristics to examine the simultaneous associations between neighborhood disorganization, maternal spanking, and aggressive behavior in early childhood using data from the Fragile Families and Child Wellbeing Study (FFCWS). Analysis was based on 2,472 children and their mothers who participated in Wave 3 (2001–2003; child age 3) and Wave 4 (2003–2006; child age 5) of the FFCWS. Results indicated that higher rates of neighborhood crime and violence predicted higher levels of child aggression. Maternal spanking in the past year, whether frequent or infrequent, was also associated with increases in aggressive behavior. This study contributes statistically rigorous evidence that exposure to violence in the neighborhood as well as the family context are predictors of child aggression. We conclude with a discussion for the need for multilevel prevention and intervention approaches that target both community and parenting factors. 相似文献
4.
信息网络发展的负面影响及对策研究 总被引:3,自引:0,他引:3
随着互联网络在我国的飞速发展及高度信息化的网络社会的到来,网络所带来的信息污染、政治渗透、网络安全等负面效应已成为信息时代必须尽快加以解决的重大课题。在对网络负面影响分析的基础上,提出了信息资源网络化建设进程中应采取的对策。 相似文献
5.
蜻蜓拍翼前飞中模型翼动态柔性变形的气动效应研究 总被引:1,自引:0,他引:1
根据蜻蜓拍翼前飞激发的流场具有St>>1/Re的特点,在理论模化框架下,本文采用势流假设,用二维变形体前、后缘脱涡的面元法研究了前飞模型蜻蜓翼在周期性拍动中动态柔性变形引起的气动力响应。通过比较柔性模型翼和刚性模型翼气动力随时间的变化,发现在下拍行程中动态柔性变形显著地提高了升力和推力;值得注意的是,蜻蜓前飞时,翼的实际柔性变形幅值恰处于一个最佳范围内,它大幅地提高了升力,同时使消耗的气动功率趋近于最低,有利于蜻蜓维持前飞状态。 相似文献
6.
运用能值理论分析宁夏荒漠化治理工程实施前后生态经济系统投入和产出的变化情况,评价该地区荒漠化治理的生态经济效应。研究表明,该地区能值产出量的增长幅度大于投入增长幅度,总能值产出结构向多元化发展;在能值投入结构方面,不可更新环境资源和可更新有机能投入量出现下降趋势;能值投资率和环境负载率呈先增加后减少的趋势,净能值产出率呈现先增后降再增长的趋势;系统的功能逐步完善,生态和经济向协调方向发展。 相似文献
7.
饮用水Ames致突变性与主要有机污染指标的关系 总被引:7,自引:1,他引:7
通过对某城市水源水、自来水及经不同组合工艺净化水Ames试验结果与主要有机污染指标的对应关系分析,发现诱发回变指数MA(TA98)主要与总有机碳有关。在此基础上进一步研究了几种常见有机微污染物与MA的关系。其研究成果对于认识饮用水致突变性,改进饮水深度处理工艺,提高饮水水质均具有指导作用。 相似文献
8.
9.
Pär Isling Poromaa 《British Journal of Sociology of Education》2017,38(3):384-402
This article examines the objective possibilities of Swedish schools to offer an equal and functional pedagogical practice for students’ acquisition of knowledge and skills. The data consist of policy documents, observations, and interviews with students, teachers, and head teachers in three educational settings distinguished by different social demographics. The focus allows for a comparative understanding of how tangible objects generate formations of schools as a relational phenomenon depending on geographic location and social background of students. The article indicates that the impact of materiality lies in its preceding power. It shapes the condition of institutions visualised in architecture, buildings, and the quality of and design of facilities and artefacts. From this material root emanates schools’ values, appeal, social status, and pedagogical organisations – school effects – that empower or weaken the school’s attraction and self-confidence. Different materialities influence each school’s institutional habitus, producing school effects with unequal educational outcomes. 相似文献
10.
乔红林 《南阳师范学院学报》2004,3(9):119-120
通过中学化学新旧教材的对比,阐明了新教材教育理念新、突出素质教育的特点,要求教师要更新观念,提高自身素质,改进教学方法,全方位提高学生的成绩和培养学生各方面的能力及素质,完成历史赋予教师的使命。 相似文献