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   15224篇
  免费   245篇
  国内免费   12篇
教育   10476篇
科学研究   1905篇
各国文化   127篇
体育   1139篇
综合类   22篇
文化理论   171篇
信息传播   1641篇
  2022年   107篇
  2021年   150篇
  2020年   227篇
  2019年   314篇
  2018年   428篇
  2017年   483篇
  2016年   437篇
  2015年   304篇
  2014年   421篇
  2013年   2508篇
  2012年   372篇
  2011年   360篇
  2010年   343篇
  2009年   286篇
  2008年   318篇
  2007年   324篇
  2006年   303篇
  2005年   257篇
  2004年   289篇
  2003年   255篇
  2002年   260篇
  2001年   331篇
  2000年   366篇
  1999年   293篇
  1998年   156篇
  1997年   192篇
  1996年   192篇
  1995年   134篇
  1994年   141篇
  1993年   128篇
  1992年   214篇
  1991年   212篇
  1990年   252篇
  1989年   238篇
  1988年   205篇
  1987年   211篇
  1986年   200篇
  1985年   239篇
  1984年   179篇
  1983年   158篇
  1982年   149篇
  1981年   128篇
  1980年   130篇
  1979年   197篇
  1978年   154篇
  1977年   130篇
  1976年   106篇
  1975年   103篇
  1974年   110篇
  1971年   103篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
In the article we solve path planning task for an agent being multirotor unmanned aerial vehicle (multicopter). We propose an approach of estimating path geometry constraints based on UAV flight dynamics model and control constraints. Than we introduce a new path finding method which takes into consideration those geometry constraints and study this method both theoretically and empirically.  相似文献   
103.
Scholars who have taken interest in Theaetetus' educational theme argue that Plato contrasts an inferior, even dangerous, sophistic education to a superior, philosophical, Socratic education. I explore the contrasting exhortations, methods, ideals and epistemological foundations of Socratic and Protagorean education and suggest that Socrates' treatment of Protagoras as educator is far less dismissive than others claim. Indeed, Plato, in Theaetetus, offers a qualified defence of both Socrates and Protagoras. Socrates and Protagoras each dwell in the middle ground between the extremes presented in the dialogue's digression, which contrasts the life of the philosopher and the life of the courtroom orator. Both Socrates and Protagoras demonstrate a serious engagement with both politics and philosophy. Theodorus presents an educational option in which theory is divorced from politics while an ignoble sophistic education is presented as political but divorced from theory. Protagorean education, in Theaetetus, emerges as superior to a base sophistic education, though it remains inferior to Socratic education.  相似文献   
104.
105.
ABSTRACT

The objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (< .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes.  相似文献   
106.
107.
108.
109.
110.
ABSTRACT

Recently, there has been much controversy over the International Association of Athletics Federation (IAAF) regulations regarding eligibility to compete and natural testosterone levels in female athletes. Much interest lies in the analysis of Caster Semenya's extraordinary performance. The objective of this work were, a) Complete an analysis of Caster Semenya's results during the 800m finals and b) search for existing similar performances by other female athletes. We analysed the results of the finals of all IAAF World Championships and Olympic Games from 1984–2016, including the 800m results of the Diamond Leagues 2016–2018. Exponential curves were fit to the data to characterise and predict performance for each event. Caster Semenya's finishing times before her ineligibility to compete and after the suspension of the IAAF hyperandrogenism regulation were found to be 1.24% and 1.49%, respectively, faster than the characteristic performance of the elite-standard in the women’s 800m final. Other female athletes, with finishing times faster than the ones predicted by the characteristic curves were also discovered. The percentage difference in performance between Caster Semenya and the other participants did not reach 3% in the 800m event. No conclusions can be drawn regarding extraordinary results ever performed during the 100m, 200m or 400m finals.  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