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   3342篇
  免费   96篇
  国内免费   44篇
教育   2357篇
科学研究   389篇
各国文化   39篇
体育   224篇
综合类   108篇
文化理论   34篇
信息传播   331篇
  2023年   24篇
  2022年   79篇
  2021年   101篇
  2020年   112篇
  2019年   146篇
  2018年   169篇
  2017年   156篇
  2016年   137篇
  2015年   160篇
  2014年   195篇
  2013年   442篇
  2012年   213篇
  2011年   180篇
  2010年   200篇
  2009年   150篇
  2008年   158篇
  2007年   129篇
  2006年   119篇
  2005年   108篇
  2004年   88篇
  2003年   59篇
  2002年   72篇
  2001年   44篇
  2000年   39篇
  1999年   17篇
  1998年   22篇
  1997年   12篇
  1996年   20篇
  1995年   9篇
  1994年   11篇
  1993年   11篇
  1992年   9篇
  1991年   14篇
  1990年   9篇
  1989年   9篇
  1988年   10篇
  1987年   5篇
  1986年   7篇
  1985年   5篇
  1984年   2篇
  1982年   3篇
  1980年   5篇
  1978年   2篇
  1975年   3篇
  1974年   2篇
  1973年   3篇
  1972年   2篇
  1971年   2篇
  1968年   1篇
  1967年   2篇
排序方式: 共有3482条查询结果,搜索用时 15 毫秒
141.
聂晓  翟小兵 《科技通报》2015,(4):215-217,221
为了提高数据库检索的智能性及个性化推荐,将改进的ART算法应用于数据库自动知识推荐。首先对基本ART算法及ART网络算法进行了描述,接着提出了改进的ART算法,最后运用实例仿真,验证该算法性能。文本采用某高校数字图书馆数据库作为仿真对象,验证其自动知识推荐的功能,同时对其资源消耗和扫描时间进行了计算仿真,实验证明,本文算法在数据库自动知识推荐过程中,所耗资源少且效率高,具有一定的研究价值。  相似文献   
142.
近年来群体性突发事件频繁发生,严重影响社会的和谐发展,研究群体性突发事件的诱发因素、发生机理对于科学预防群体性突发事件具有重要指导作用。立足搜集的群体性突发事件资料和案例,运用扎根理论得出公平性这一群体性突发事件的核心诱发因素和文化冲击、个人需求等8个主要诱发因素。在此基础上阐述了基于“公平性”的群体性突发事件发生机理,揭示了群体性突发事件发生的过程。最后根据发生机理提出了预防群体性突发事件发生的建议。  相似文献   
143.
In this methodological discussion, the authors detail and reflect on the processes of using photo-elicitation interviewing as a way to align with positive qualitative methodologies, to gain access to participant beliefs and values, and to highlight participant voices through their choices of words and visuals. A review of the literature and an overview of the educational research experiences leading to the discussion are included. Next, the discoveries regarding what is methodologically new and/or valuable concerning this visual method is presented. In the final section, the authors reflexively contemplate aspects of visual methodological processes in an effort to address methodological crossroads of potential and tension including: (1) the potential of decontextualized photos, (2) photos as metaphors of meaning, (3) photos as representations of inherent meaning, (4) participant empowerment, and (5) graphic representation or graphic portraits.  相似文献   
144.
This article takes the concept and some of the existing applications of socialbots—software robots that operate on social networking sites and present themselves as human users—as an occasion to trace the evolution of online sociality. The argument mobilizes theories of social rationalization from Max Weber to contemporary critical theory to demonstrate that the appearance of automated profiles (socialbots) on social networking platforms can be seen as a logical step in the progressive enclosure of online social interaction in standardized, simplified, and trivialized forms, frames, and gestures. Critical questions concerning what the growth of robo-sociality may mean for individual users and the online public sphere are posed with a view to charting the directions for a needed public debate.  相似文献   
145.
详细介绍了一类KF促进的酚与三氟甲基三甲基硅烷的三甲基硅基化反应.反应具有良好的官能团适用范围,如带有甲基、甲氧基、碘、溴、氯、氟及三氟甲基等官能团的酚都能够顺利发生该转化.该方法给出了一类实用性强的三甲基硅基芳醚的合成途径.  相似文献   
146.
147.
148.
为适应新军事变革,培养我军官兵能打胜仗的心理素质,必须构建紧贴部队、紧贴实战的战斗心理训练体系。通过对部队现有军事体育训练资源的系统分析,探讨从现有军事体育训练资源中剥离出战斗心理素质的训练元素,构建作战部队官兵战斗心理训练的内容和方法体系,为拓宽军事体育的训练功能提供理论和实践参考。  相似文献   
149.
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells.  相似文献   
150.
A motor skills assessment could be helpful in talent development by estimating essential perceptuo-motor skills of young players, which are considered requisite to develop excellent technical and tactical qualities. The Netherlands Table Tennis Association uses a motor skills assessment in their talent development programme consisting of eight items measuring perceptuo-motor skills specific to table tennis under varying conditions. This study aimed to investigate this assessment regarding its reproducibility, internal consistency, underlying dimensions and concurrent validity in 113 young table tennis players (6–10 years). Intraclass correlation coefficients of six test items met the criteria of 0.7 with coefficients of variation between 3% and 8%. Cronbach’s alpha valued 0.853 for internal consistency. The principal components analysis distinguished two conceptually meaningful factors: “ball control” and “gross motor function.” Concurrent validity analyses demonstrated moderate associations between the motor skills assessment’s results and national ranking; boys r = ?0.53 (< 0.001) and girls r = ?0.45 (= 0.015). In conclusion, this evaluation demonstrated six test items with acceptable reproducibility, good internal consistency and good prospects for validity. Two test items need revision to upgrade reproducibility. Since the motor skills assessment seems to be a reproducible, objective part of a talent development programme, more longitudinal studies are required to investigate its predictive validity.  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