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   1484篇
  免费   11篇
  国内免费   101篇
教育   601篇
科学研究   369篇
各国文化   1篇
体育   16篇
综合类   17篇
文化理论   9篇
信息传播   583篇
  2023年   6篇
  2022年   6篇
  2021年   11篇
  2020年   35篇
  2019年   20篇
  2018年   22篇
  2017年   21篇
  2016年   15篇
  2015年   12篇
  2014年   83篇
  2013年   173篇
  2012年   88篇
  2011年   128篇
  2010年   87篇
  2009年   116篇
  2008年   103篇
  2007年   123篇
  2006年   120篇
  2005年   102篇
  2004年   100篇
  2003年   73篇
  2002年   62篇
  2001年   30篇
  2000年   25篇
  1999年   17篇
  1998年   9篇
  1997年   5篇
  1996年   1篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
排序方式: 共有1596条查询结果,搜索用时 109 毫秒
91.
【目的】找出大气科学类期刊DOI注册和应用中存在的问题并及时解决,充分发挥DOI在科技期刊的作用,普及DOI检索在科研中的应用。【方法】调查分析2014版《中国科技期刊引证报告(核心版)》大气科学类核心期刊使用DOI的现状,包括DOI的注册及标注、文后参考文献著录,以及DOI的解析情况。【结果】大气科学类期刊DOI注册较成熟,但是DOI的应用和宣传远远不够,特别表现在文后参考文献的著录、首页的推荐引用格式,以及解析不准确等方面。【结论】提出科技期刊应做好DOI注册的后期工作,并加大DOI的宣传力度,提高DOI解析的正确性,在DOI的应用方面早日与国际接轨。  相似文献   
92.
Firms vary greatly in their rates of creating and adopting technological and organizational innovations, in part because of their choice of reference group. We argue that the selection of a reference group is a crucial and neglected source of firm heterogeneity. Comparisons to the average of other firms in a population cause most firms to adopt innovations once they are widely accepted. A distinctive feature of the minority of innovating firms that create innovations or adopt them early is that they compare themselves with, compete with, and try to differ from other innovating firms, whereas the majority of firms compare themselves with, and conform to, a broader group of firms. We elaborate this argument based on the behavioral theory of the firm and institutional theory, and test it on a two-period survey on adoptions of innovative organizational forms in Europe and the US. The analysis shows the predicted differences in the adoption patterns of innovating and imitating firms.  相似文献   
93.
Reference Framework 5架构及其在数字图像处理中的应用   总被引:1,自引:0,他引:1  
深入分析了Reference Framework(RF)5的原理和缝构,说明了各数据元素的作用及相点关系,并通过动态目标检测例程详细说明了Eeference Framework5在数字图像处理中的应用。  相似文献   
94.
基于虚拟现实建模语言VRML和Java编程技术,将两者结合运用构建一个应用于数字科技馆中的交互式虚拟产品设计系统,使青少年可以通过互联网协同多人进行产品设计。  相似文献   
95.
Communication researchers and social scientists are quickly discovering the value of data that exists in the postings of members of Internet e-mail, Usenet, and real-time groups. The ability to communicate with one's peers, no matter how esoteric the interests, is causing an explosion in the number of new virtual communities. The interpersonal dynamics of these groups are increasingly coming under the scrutiny of academic research. The publicly available archived records of Internet virtual communities are being analyzed for a wide variety of research interests. The ability to do naturalistic observations of group dynamics, as they are exhibited in these exchanges of text, has captured the attention of many researchers. The institutional review boards of major universities are granting researchers exempt or expedited (exempt from full review) status for this work, due to the public nature of the notes being analyzed. These studies often involve the lack of informed consent, where the group members under study are unaware they are being monitored. There is a potential for psychological harm to the members of these groups, depending on the way results are reported. This article explores the ethical considerations that must be taken into account to protect cyberspace participants. The guidelines proposed are based on the American Psychological Association ethical guidelines for use of human subjects in research. An explanation is offered as to how such guidelines can best be applied to the study of Internet communities. The constructs of Group Accessibility (the public/private nature of the actual cyberspace occupied by a group) and Perceived Privacy (the level of privacy that group members assume they have) are defined and proposed as two dimensions by which individual Internet communities may be evaluated in order to assure the ethical reporting of research findings.  相似文献   
96.
虚拟仪器是由软件实现的.其软件开发平台是LabVIEW。VISA是在所有LabVIEW工作平台上控制VISA、GPIB、RS-232以及其他种类仪器的单接口程序库,通过LabVIEW平台中的VISA模块编写控制程序,可以进行仪器控制。本文以串行通信为例.用LabVIEW构建仪器控制进行串行设备通信.在虚拟环境中使用VISA功能模块向串行设备读写数据,缩短了项目开发周期,提高了开发效率。  相似文献   
97.
Physical versus virtual manipulative experimentation in physics learning   总被引:3,自引:0,他引:3  
The aim of this study was to investigate whether physical or virtual manipulative experimentation can differentiate physics learning. There were four experimental conditions, namely Physical Manipulative Experimentation (PME), Virtual Manipulative Experimentation (VME), and two sequential combinations of PME and VME, as well as a control condition (i.e., traditional instruction with absence of PME or VME). Undergraduate students' understanding of physics concepts in the domain of heat and temperature was tested in a pre- and posttest design that involved 182 participants assigned to the four experimental groups and 52 participants assigned to the control group. Conceptual tests were administered to assess students' understanding before, during and after instruction. The analyses revealed that the four experimental conditions were equally effective in promoting students' understanding of concepts in the domain of heat and temperature and better than the control condition; hence, manipulation, either physical or virtual manipulation, and not physicality, as such, at least in a context like the one of the present study, is important in physics learning.  相似文献   
98.
实时虚拟参考咨询服务在图书馆服务中发挥着积极且重要的作用。清华大学图书馆基于开源软件A.L.I.C.E.开发出实时智能聊天机器人"小图",提供参考咨询、图书搜索、自我学习等多种服务,并将其推广至社交网络,取得良好的效果。  相似文献   
99.
Web2.0环境下,虚拟社区作为社区成员进行情感交流、信息传递、知识共享的平台日益受到人们的青睐,但只有少数虚拟社区能成功地保持成员数量并激发其进行知识创新,因此研究虚拟社区中知识创新的影响因素对提高知识创新服务尤为重要。基于社会资本论,并结合前人相关研究成果,本文研究虚拟社区中知识创新的影响因素,建立假设模型,然后通过实证数据分析,揭示出个人价值、声誉、群体交互和认可感对知识创新数量和质量有显著正面影响。本研究成果将有助于虚拟社区更好地开展知识创新服务。  相似文献   
100.
在对中美高校图书馆数字参考咨询2.0服务的网络调查的基础上,以南京高校为例,通过问卷调查,了解大学生对数字参考咨询的认知和使用情况,以及对数字参考咨询2.0服务的需求情况。最后对开展数字参考咨询2.0服务提出建议:在参考咨询中综合应用多项Web2.0技术,加强不同技术的融合,扩大参考咨询2.0服务范围,转变服务模式,提高参考咨询馆员专业素质,完善服务管理,加强参考咨询2.0的推广,开展用户培训。  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