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   21991篇
  免费   317篇
  国内免费   14篇
教育   16077篇
科学研究   1686篇
各国文化   238篇
体育   1778篇
综合类   10篇
文化理论   214篇
信息传播   2319篇
  2021年   176篇
  2020年   296篇
  2019年   455篇
  2018年   624篇
  2017年   657篇
  2016年   612篇
  2015年   414篇
  2014年   510篇
  2013年   4357篇
  2012年   512篇
  2011年   577篇
  2010年   422篇
  2009年   392篇
  2008年   590篇
  2007年   432篇
  2006年   501篇
  2005年   378篇
  2004年   323篇
  2003年   343篇
  2002年   364篇
  2001年   445篇
  2000年   399篇
  1999年   369篇
  1998年   229篇
  1997年   258篇
  1996年   277篇
  1995年   289篇
  1994年   253篇
  1993年   246篇
  1992年   342篇
  1991年   313篇
  1990年   306篇
  1989年   329篇
  1988年   327篇
  1987年   272篇
  1986年   268篇
  1985年   286篇
  1984年   246篇
  1983年   299篇
  1982年   235篇
  1981年   232篇
  1980年   236篇
  1979年   298篇
  1978年   230篇
  1977年   207篇
  1976年   197篇
  1975年   170篇
  1974年   158篇
  1973年   152篇
  1971年   133篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
123.
The United Kingdom's Department for Education has recently changed the nature of the AS‐level examinations normally taken by students aspiring to enter higher education degree courses one year into their post‐compulsory education. In the face of protests from universities and other institutions that this would both harm students’ progression towards the A‐level qualifications, on which entry to English universities is normally based, and make it difficult for universities determining which of their applicants were best placed to benefit from their degree courses, the Department conducted research which it claimed showed that degree outcome could be predicted as well from the results of GCSE examinations taken one year before AS‐levels as from AS‐levels themselves. This paper critiques those analyses and their conclusions showing, through a re‐analysis and extended interpretation of the Department's data, that AS‐levels provide a more reliable predictor of degree performance in 2011 than GCSEs and that many students who performed better at AS‐level than at GCSE gained a place, and performed well, at a university with high entrance standards.  相似文献   
124.
125.
126.
127.
128.
129.
Research suggests that spatial ability may predict success in complex disciplines including anatomy, where mastery requires a firm understanding of the intricate relationships occurring along the course of veins, arteries, and nerves, as they traverse through and around bones, muscles, and organs. Debate exists on the malleability of spatial ability, and some suggest that spatial ability can be enhanced through training. It is hypothesized that spatial ability can be trained in low-performing individuals through visual guidance. To address this, training was completed through a visual guidance protocol. This protocol was based on eye-movement patterns of high-performing individuals, collected via eye-tracking as they completed an Electronic Mental Rotations Test (EMRT). The effects of guidance were evaluated using 33 individuals with low mental rotation ability, in a counterbalanced crossover design. Individuals were placed in one of two treatment groups (late or early guidance) and completed both a guided, and an unguided EMRT. A third group (no guidance/control) completed two unguided EMRTs. All groups demonstrated an increase in EMRT scores on their second test (P < 0.001); however, an interaction was observed between treatment and test iteration (P = 0.024). The effect of guidance on scores was contingent on when the guidance was applied. When guidance was applied early, scores were significantly greater than expected (P = 0.028). These findings suggest that by guiding individuals with low mental rotation ability “where” to look early in training, better search approaches may be adopted, yielding improvements in spatial reasoning scores. It is proposed that visual guidance may be applied in spatial fields, such as STEMM (science, technology, engineering, mathematics and medicine), surgery, and anatomy to improve student's interpretation of visual content. Anat Sci Educ. © 2018 American Association of Anatomists.  相似文献   
130.
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   
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