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   2347篇
  免费   45篇
  国内免费   141篇
教育   802篇
科学研究   706篇
体育   33篇
综合类   128篇
信息传播   864篇
  2023年   16篇
  2022年   30篇
  2021年   41篇
  2020年   43篇
  2019年   51篇
  2018年   45篇
  2017年   42篇
  2016年   33篇
  2015年   55篇
  2014年   116篇
  2013年   174篇
  2012年   192篇
  2011年   200篇
  2010年   134篇
  2009年   145篇
  2008年   175篇
  2007年   192篇
  2006年   164篇
  2005年   146篇
  2004年   122篇
  2003年   103篇
  2002年   108篇
  2001年   89篇
  2000年   51篇
  1999年   21篇
  1998年   9篇
  1997年   5篇
  1996年   1篇
  1995年   4篇
  1994年   4篇
  1993年   4篇
  1992年   7篇
  1991年   6篇
  1990年   1篇
  1989年   1篇
  1981年   1篇
  1957年   2篇
排序方式: 共有2533条查询结果,搜索用时 15 毫秒
41.
网络阅读指导研究   总被引:22,自引:0,他引:22  
网络阅读指导并非传统阅读指导的简单移植。网络阅读指导与网络、网络阅读的特点密切相关,并且存在多种形式。同时,网络阅读指导面临着目录式搜索引擎的冲击。  相似文献   
42.
ISI Web of Knowledge跨库检索功能与操作技巧   总被引:3,自引:0,他引:3  
ISI web of Knowledge是新一代的学术信息资源整合体系,是Web of science的最新升级平台。本文主要介绍了这一体系的跨库检索功能及其操作技巧。  相似文献   
43.
This research examines privacy law and Human Flesh Search (HFS) on the Chinese Internet. HFS is spontaneous, widely participated search and publication of targeted individuals’ personal information on the Internet. This research sees HFS as an important form of non-institutional information gathering and publication, and argues that the regulation of HFS is not only about privacy but also line-drawing for information collection and dissemination in the digital setting. Therefore, legal instruments and court cases in relation to HFS and online privacy must be assessed as important components of the Chinese state’s Internet regulatory scheme. This research finds that the paired concepts of ‘flexibility and populism,’ key features of legal reform and development in contemporary China, are highly relevant to analyze the growth of digital privacy laws in China. The political-legal authorities’ experimentation and innovation in the development of the law shed important light on how China’s Internet governance adapts to changing circumstances and strives to keep pace with profound social transformations in new technological environments.  相似文献   
44.
45.
ABSTRACT

Adding multiple sources of information in the display of Web search results may negatively affect users’ perceptual experience and information-seeking behavior. This claim was established by investigating the impact of different Web search compositions on users’ ability to extract specific information. In this article, we assumed that the quantity and order of different compositions (areas) in the Web search results page may contribute to individual’s ability to find information relevant to their search queries. An eye-tracking device was used to observe and compare the perceptual behavior of 14 users in an information-seeking task. The results showed that the use of different compositions in the display of Web results page significantly influenced users’ perceptual experience by reducing their attention to the organic results area. The quantity of these compositions was found to greatly increase the cognitive load of users when attempting to retrieve information from the organic area, which negatively affects their information-seeking performance. Our finding provides a rationale for further studies to consider the impact of quantity and order of Web page compositions on individuals’ perceptual attention and cognitive load in information-seeking task settings.  相似文献   
46.
47.
因特网上中国专利检索系统的比较分析   总被引:2,自引:0,他引:2  
专利检索在各行各业的生产、科研中应用非常广泛。对国内目前的6种专利检索系统数据库进行介绍和比较,可以帮助读者在较短的时间内检索到所需的专利。  相似文献   
48.
讨论了在Internet上进行信息检索的一般方法,详细地介绍了搜索引擎Google在信息检索领域的作用和网页搜索、图像搜索、新闻组搜索、主题目录的使用方法,分析归纳了它的逻辑运算能力,以及其他几种杰出的特殊功能,最后对它的性能进行了初步的评价。  相似文献   
49.
This study examined the contribution of situational probability information to the perceptual and cognitive processes underlying decision-making behaviour during in situ Karate performance. Experts and novices were required to make decisions about various attacks in different fight scenarios. The order in which the fight situations were presented was modified in order to provide advanced probability information and identify whether fighters were able to use the latter information to make better decisions. Specifically, one of the attacks was repeated every four actions. Results revealed that experts were more accurate and faster than their less skilled counterparts to block and counterattack the opponent. The experts picked up the occurrence of the attack pattern after the fifth repetition whereas novices did not. This enabled experts to improve decision time and decision accuracy. Findings suggest that such superiority could stem from the perceptual and cognitive skills possessed by the experts, thus giving them the opportunity to recognise a situation more easily. This was reinforced by gaze behaviour which demonstrated that experts used a more efficient search strategy involving fewer fixations of longer duration on a lesser number of areas relative to the novices. Moreover, experts generated more refined karate-specific knowledge structures compared with the novices.  相似文献   
50.
太阳能空间斯特林热机性能的优化分析   总被引:1,自引:0,他引:1  
建立太阳能驱动的空间斯特林热机的循环模型,应用有限时间热力学理论和太阳能集热器的辐射损失模型,研究受热阻和回热损失影响的太阳能斯特林热机循环性能,导出空间热机效率的基本优化关系,确定太阳能集热器的最佳工作温度和效率界限,讨论各种不可逆性对空间热机性能的影响,所得结论可为太阳能空间斯特林热机的优化设计提供新的理论指导。  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