全文获取类型
收费全文 | 31440篇 |
免费 | 447篇 |
国内免费 | 193篇 |
专业分类
教育 | 26317篇 |
科学研究 | 2557篇 |
各国文化 | 21篇 |
体育 | 1056篇 |
综合类 | 1098篇 |
文化理论 | 8篇 |
信息传播 | 1023篇 |
出版年
2024年 | 6篇 |
2023年 | 255篇 |
2022年 | 409篇 |
2021年 | 718篇 |
2020年 | 1118篇 |
2019年 | 1067篇 |
2018年 | 776篇 |
2017年 | 862篇 |
2016年 | 857篇 |
2015年 | 954篇 |
2014年 | 2029篇 |
2013年 | 3631篇 |
2012年 | 2726篇 |
2011年 | 2475篇 |
2010年 | 1556篇 |
2009年 | 1554篇 |
2008年 | 1749篇 |
2007年 | 1870篇 |
2006年 | 1797篇 |
2005年 | 1467篇 |
2004年 | 1234篇 |
2003年 | 979篇 |
2002年 | 761篇 |
2001年 | 538篇 |
2000年 | 311篇 |
1999年 | 124篇 |
1998年 | 71篇 |
1997年 | 57篇 |
1996年 | 33篇 |
1995年 | 15篇 |
1994年 | 28篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 9篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1957年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 640 毫秒
1.
Higher education institutions are trying to provide more flexibility and individualization, which is mainly realized through the use of new technologies and implemented in online or blended learning designs. This systematic review aims to investigate the impact of replacing classroom time with an online learning environment. The meta-analysis (k = 21 effect sizes) applied strict inclusion criteria concerning research design, measurement of learning outcomes and implementation of blended learning. The estimated effect size (Hedge's g) was positive, although not significantly different from zero and the confidence interval [-0.13, 0.25], suggesting that overall differences between blended and conventional classroom learning are small, and, at best, very small negative or moderate positive effects are plausible. This means that despite a reduction in classroom time between 30 and 79 per cent, equivalent learning outcomes were found. Consequently, blended learning with reduced classroom time is not systematically more or less effective than conventional classroom learning. 相似文献
2.
The article documents findings from a pilot study undertaken in 2012–2013 in a special needs secondary school in the England, that trialled the use of a multimedia advocacy tool, “The RIX Wiki”. The trial was part of the pathfinder programme, which aimed to reform existing Special Education Needs provision, from the system of statementing to one of developing education health care plans. The reforms became enshrined in the Children and Families Act (2014). The findings were overall positive and helped with person-centred planning processes. The discussion is framed within current and future policy directives. We argue that multimedia advocacy approaches and software tools, like the “RIX Wiki” will have a continued role to play in ensuring the needs, aspirations and choices of children and young people with learning disabilities remain central. 相似文献
3.
4.
This study examined the effects of a syllable-based reading intervention for German second graders who demonstrated difficulties in the recognition of written words. The intervention focused on fostering word reading via syllable segmentation. The materials consisted of the 500 most frequent syllables typically read by 6- to 8-year-old children. The aims were to practice phonological recoding, consolidate orthographic representations of syllables, and routinize the access to these representations. Compared to children randomly assigned to a wait-list group, poor readers in the treatment condition showed significant improvements in standardized measures of phonological recoding, direct word recognition, and text-based reading comprehension after the 24-session intervention. Poor readers in the treatment condition also showed greater improvements in development of word recognition compared to children with efficient word recognition skills. The results provide evidence that a syllable-based reading intervention is a promising approach to increase struggling readers’ word recognition skills, which in turn will improve their reading comprehension. 相似文献
5.
Edgardo Ferretti Leticia Cagnina Viviana Paiz Sebastián Delle Donne Rodrigo Zacagnini Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published. 相似文献
6.
基于深度学习的中文专利自动分类方法研究 总被引:2,自引:0,他引:2
[目的/意义] 面向当前国内专利审查和专利情报分析工作中对于海量专利分类的客观需求,设计了7种基于深度学习的专利自动分类方法,对比各种方法的分类效果,从而助力专利分类效率和效果的提升。[方法/过程] 针对传统机器学习方法存在的缺陷,基于Word2Vec、CNN、RNN、Attention机制等深度学习技术,考虑专利文本语序特征、上下文特征以及分类关键特征,设计Word2Vec+TextCNN、Word2Vec+GRU、Word2Vec+BiGRU、Word2Vec+BiGRU+TextCNN等7种深度学习模型,以中国专利为例,选取IPC主分类号的"部"作为分类依据,对比这7种模型与3种传统分类模型在中文专利分类任务中的效果。[结果/结论] 实证研究效果显示,采用考虑语序特征、上下文特征及强化关键特征的深度学习方法进行中文专利分类具有更优的分类效果。 相似文献
7.
8.
针对多旋翼无人机目标的识别问题,提出一种基于伽柏(Gabor)变换的瞬时频率估计与快速傅里叶变换(FFT)相结合的微多普勒特征提取算法。首先建立多旋翼无人机旋翼回波模型,并通过仿真分析叶片数目、旋翼转速和初始相位等参数对微多普勒特征的影响,利用Gabor变换得到时频特征。在此基础上通过瞬时频率极大值法提取微多普勒频率,并对瞬时频率采用FFT提取旋翼数和转动频率,从而获得叶片长度估计值。实测数据验证了该算法较为准确地提取无人机的微多普勒参数。 相似文献
9.
Review helpfulness is attracting increasing attention of practitioners and academics. It helps in reducing risks and uncertainty faced by users in online shopping. This study examines uninvestigated variables by looking at not only the review characteristics but also important indicators of reviewers. Several significant review content and two reviewer variables are proposed and an effective review helpfulness prediction model is built using stochastic gradient boosting learning method. This study derived a mechanism to extract novel review content variables from review text. Six popular machine learning models and three real-life Amazon review data sets are used for analysis. Our results are robust to several product categories and along three Amazon review data sets. The results show that review content variables deliver the best performance as compared to the reviewer and state-of-the-art baseline as a standalone model. This study finds that reviewer helpfulness per day and syllables in review text strongly relates to review helpfulness. Moreover, the number of space, aux verb, drives words in review text and productivity score of a reviewer are also effective predictors of review helpfulness. The findings will help customers to write better reviews, help retailers to manage their websites intelligently and aid customers in their product purchasing decisions. 相似文献
10.
体育教育专业学生英语学习方式调查研究 总被引:3,自引:0,他引:3
孟悦 《沈阳体育学院学报》2003,22(4):88-90
报告了对沈阳体育学院体育教育专业学生外语学习方式倾向的调查研究,并以问卷为研究工具。运用定量研究方法,分析了个体差异如性别、外语水平等对学生学习方式倾向的影响。结果显示学生喜欢多种外语学习方式,外语成绩优、差学生6种学习方式均无显著差异,男生比女生更喜欢听觉学习,女生比男生更喜欢视觉学习。据此提出外语教师应根据学生的认知特点灵活运用各种教学方式,并指导学生调整和扩展多种学习风格以促进教与学的协调发展。 相似文献