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   2777篇
  免费   51篇
  国内免费   83篇
教育   1599篇
科学研究   692篇
各国文化   3篇
体育   100篇
综合类   112篇
文化理论   3篇
信息传播   402篇
  2024年   2篇
  2023年   29篇
  2022年   26篇
  2021年   32篇
  2020年   66篇
  2019年   70篇
  2018年   76篇
  2017年   85篇
  2016年   61篇
  2015年   62篇
  2014年   147篇
  2013年   387篇
  2012年   187篇
  2011年   165篇
  2010年   150篇
  2009年   152篇
  2008年   142篇
  2007年   186篇
  2006年   157篇
  2005年   148篇
  2004年   124篇
  2003年   98篇
  2002年   78篇
  2001年   75篇
  2000年   44篇
  1999年   27篇
  1998年   26篇
  1997年   30篇
  1996年   22篇
  1995年   9篇
  1994年   7篇
  1993年   12篇
  1992年   6篇
  1991年   6篇
  1990年   10篇
  1989年   3篇
  1988年   3篇
  1985年   1篇
排序方式: 共有2911条查询结果,搜索用时 15 毫秒
131.
Educational assessment in the Republic of Korea reflects social and cultural perspectives, as most assessments are considered as a ‘gatekeeper’ of one’s success in life, in terms of entering an elite school or having a better career. This paper presents a profile of the education system, especially focusing on the college entrance examination system in the Republic of Korea, and discusses the washback effect of the high-stake exam, the College Scholastic Ability Test, on stakeholders and the entire society. Furthermore, this paper will discuss the ways to improve the education policy, particularly the college entrance system, with emphasis on implications for future assessment reform from a standardised high-stake test to move towards the formative assessment.  相似文献   
132.
As the advance of learning technologies and analytics tools continues, learning management systems (LMSs) have been required to fulfil the growing expectations for smart learning. However, the reality regarding the level of technology integration in higher education differs considerably from such expectations or the speed of advances in educational technologies. This research aimed to evaluate the current activation levels and usage patterns of a LMS. A large data-set was analysed, which included the online activity information from 7940 courses. Through data pre-processing, general indicators reflecting login frequencies of the virtual campus and activity-based indicators presenting the activation patterns of diverse functions provided by Moodle were derived. Activity theory was applied to interpret the results of analysis, since it has been recognised as a powerful framework to understand phenomena encompassing interactive systems. Further, time-series investigation over three consecutive semesters allowed observation of historical changes. The results revealed considerably low use of the virtual campus with only slight changes, as well as significantly different activity patterns across course attributes and colleges. Contradictions among components in the activity system are discussed, along with the implications for improving teaching and learning with LMS in higher education.  相似文献   
133.
In response to the increasing recognition of the need for sustainable food systems, research on students’ and educators’ knowledge of food systems and sustainability more broadly has grown but has generally focused on what people ‘fail’ to understand. Moving away from this deficit approach, the present study used semi-structured interviews to explore how 12 pre-service teachers (PSTs) in the US consider sustainability in terms of the trade-offs – or concurrent costs and benefits – associated with using different agricultural resources over short, medium, and long terms. Drawing upon the constructs of framing, metacognition, and complex causality, the study found that the majority of PSTs referred to indirect experiences of seeing or hearing about agricultural resources to demonstrate stable knowledge of short-term trade-offs and construct tentative knowledge about medium-term trade-offs. Few described long-term trade-offs. Most participants also acknowledged some gaps in their knowledge in discussing trade-offs across the different time scales. Findings suggest the importance of leveraging and building upon educators’ (and ultimately students’) prior experiences to build their understanding of complex trade-offs that underlie food systems. The study also illustrates the value of using the concept of trade-offs across time scales to explore people’s conceptions and understandings of sustainability.  相似文献   
134.
孙华梅  黄梯云 《预测》2004,23(1):71-73
本文对决策支持系统从管理信息系统析取数据的有关问题进行研究。提出了数据析取系统的四种模式,研究了它们的实现方式,并介绍了在客户关系管理中的应用。  相似文献   
135.
136.
基于耗散与灰关联熵的RIS演化机制研究   总被引:2,自引:0,他引:2  
李柏洲  朱晓霞 《科学学研究》2007,25(6):1239-1243
 本文在论证区域创新系统(RIS)是一种耗散结构的基础上,以各评价创新能力的指标为序参量,来描述RIS的有序性和演化方向。应用耗散结构理论和灰色系统理论,把灰关联度和熵结合起来,以序参量为基础,建立了基于灰关联熵的RIS演化方向判别模型,并以黑龙江省为例对该模型的研究结果进行了验证,为RIS分析提供了一种崭新的研究思路。  相似文献   
137.
王肖  董利达  吴维敏 《科技通报》2004,20(4):269-274
基于受控Petri网的离散事件监控器按实现形式可分为逻辑型控制器和结构型控制器.由于结构型控制器具有控制动作的计算速度快,被控对象和监控器的描述形式统一等优点,而受到很多研究人员的青睐.然而,由于“或逻辑”线性约束条件的非凸状态空间的本质,用结构型控制器实现该线性约束条件将比较困难.在本文中,作者首先回顾了这一问题的起源及其意义,接着详细讨论了当前用结构型控制器实现该类状态规范的主流方法及它们各自存在的优缺点,并就某些方法提出了改进措施.最后,作者对今后的研究方向进行了预测和展望.  相似文献   
138.
系统生物学研究进展   总被引:29,自引:0,他引:29  
人类基因组计划把生物学由分子生物学时代推向系统生物学时代,生物学由分解转向整合,由叙述科学转变为定量预测科学。  相似文献   
139.
In this paper, we address the sampling and control issues for switched linear systems. Under synchronous switching and piecewise constant control, a continuous-time switched system is naturally related to a discrete-time sampled-data system. We prove that, with almost any sampling rate, the controllable subspace will be preserved for a switched linear system. We also investigate the possibility of achieving controllability using regular switching mechanisms. We show that, to achieve controllability for a switched linear system, it is sufficient to use cyclic and synchronous switching paths and constant control laws.  相似文献   
140.
梶雅範 《科学学研究》2003,21(4):352-357
本文阐明了门捷列夫于 186 9年 2月 17日做出元素周期律这一伟大发现的前提条件和历史脉络 ,并在此基础上通过将门捷列夫的工作与其同时代人进行比较研究 ,从新的视角上展示了门捷列夫伟大发现的方法论意义和特色。  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