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   5567篇
  免费   71篇
  国内免费   138篇
教育   2900篇
科学研究   1085篇
各国文化   149篇
体育   283篇
综合类   223篇
文化理论   15篇
信息传播   1121篇
  2024年   1篇
  2023年   61篇
  2022年   78篇
  2021年   135篇
  2020年   226篇
  2019年   210篇
  2018年   197篇
  2017年   189篇
  2016年   177篇
  2015年   162篇
  2014年   350篇
  2013年   719篇
  2012年   440篇
  2011年   404篇
  2010年   315篇
  2009年   324篇
  2008年   346篇
  2007年   322篇
  2006年   265篇
  2005年   196篇
  2004年   154篇
  2003年   139篇
  2002年   99篇
  2001年   79篇
  2000年   56篇
  1999年   23篇
  1998年   16篇
  1997年   23篇
  1996年   21篇
  1995年   2篇
  1994年   4篇
  1993年   3篇
  1992年   11篇
  1991年   4篇
  1990年   1篇
  1989年   3篇
  1985年   5篇
  1984年   3篇
  1983年   3篇
  1982年   6篇
  1981年   1篇
  1979年   1篇
  1978年   1篇
  1976年   1篇
排序方式: 共有5776条查询结果,搜索用时 265 毫秒
71.
使用网络分析方法,揭示了创新网络-技术联系和交融-技术协作,会出现一种技术联结体、技术整体和技术共同体的现象,基于对这种现象的分析,从共同体建设4个方面,提供了强化技术联系联结、力图驾驭这种技术共同体的着力点和方法,以提高创新成功率和创新网络素质。  相似文献   
72.
农民工是当前我国城市社会中一个重要的劳动群体,但他们却几乎被完全排斥在了社会保障的体制之外。目前,虽然城市农民工社会保障问题已经引起社会各界的广泛关注,但季节性农民工的社会保障问题仍未引起重视。针对季节性农民工这一特殊群体的社会保障问题做了一个分析,提出了解决季节性农民工社会保障问题的基本原则和基本制度框架。  相似文献   
73.
This article spotlights the need to develop capacity for ICT policy and regulation within developing countries. It argues that capacity should to be developed among all stakeholders, not solely within government agencies, because that would enable effective participation by many players in the regulatory process. The resulting participatory regulatory process will in turn increase accountability and procedural legitimacy. The article examines different approaches to developing in situ expertise, especially just-in-time learning and open-source research.  相似文献   
74.
Industrial districts as local networks of small and medium enterprises (SMEs) rooted their competitiveness in a mix of economic relationships and social ties. Recently, network technologies have promised gains of efficiency through a reduction in transaction costs and showed new commercial opportunities for small firms. Despite the morphological similarities between industrial districts and network technologies, a longitudinal analysis of ICT diffusion within Italian districts shows that the foreseen convergence between the district economic model and new technologies should not be taken for granted. The observed specific evolutionary paths concerning technology innovation in local systems also opens-up issues of economic policy.  相似文献   
75.
郑茜 《科技管理研究》2020,40(24):19-25
对科技奖励作用于社会创新的机理加以研究,认为承认是科技奖励的本质特征,科技奖励以“动机+资源+环境”的模式推动社会创新进程和成果转化:通过承认机制激发科研人员的需求;通过激励机制强化科研人员的创新动机;通过导向机制引导优势资源向重点发展技术领域、产业方向聚集;通过竞争机制筛选优秀科研成果和人才,营造良好的社会创新环境。而在这种模式下取得的经济效益又用于加大科技奖励投入,循环往复地推动社会创新不断发展。以广东省科学技术奖为例研究其对社会创新的作用机制,认为其主要通过控制奖励数量、提高奖金额度、调整奖项结构、提升奖励质量等方式发挥科技奖励的承认、激励导向和竞争作用。在此基础上分析广东省科技奖励体系存在的问题,提出发挥民间力量设奖、规范奖后派生待遇、提高个人奖项权重、加大对青年科学家支持力度等对策建议。  相似文献   
76.
This paper presents the ongoing case study of a large pharmaceutical organisation currently undertaking a number of changes to their work practices. These collaborative changes are being facilitated by groupware systems. In many instances this has led to the rejection of or resistance to the more complex tools. The paper outlines research, based on a perspective informed by structuration theory, that provides the organisation with an approach to supporting staff in this new ‘collaborative environment’. An example, drawn from the case study, shows how such support might be developed and presents a set of recommendations for supporting a particular group, based on this research schema.  相似文献   
77.
基于组合神经网络的聚合物质量预测   总被引:2,自引:0,他引:2  
介绍了一种将组合神经网络用于聚合物质量预测的方法.由定量数据建立的单一神经网络模型往往缺乏泛化能力,而使用组合神经网络模型则可以显著改善模型的泛化能力.由于在建立组合神经网络模型过程中,合适的组合权重对模型是否具有良好预测性能是非常重要的,因此采用了岭回归方法来选择合适的组合权重.所提出的方法已成功应用于PVC颗粒特性的预测研究中。研究结果表明,与单一神经网络模型相比,组合神经网络模型具有更佳的模型预测精度和鲁棒性.  相似文献   
78.
In this paper, we introduce a new architecture of genetic algorithms (GA)-based self-organizing polynomial neural networks (SOPNN) and discuss a comprehensive design methodology. Let us recall that the design of the “conventional” PNNs uses an extended group method of data handling (GMDH) and exploits polynomials (such as linear, quadratic, and modified quadratic functions) as well as considers a fixed number of input nodes (as being selected in advance by a network designer) at polynomial neurons (or nodes) located in each layer. The proposed GA-based SOPNN gives rise to a structurally optimized structure and comes with a substantial level of flexibility in comparison to the one we encounter in conventional PNNs. The design procedure applied in the construction of each layer of a PNN deals with its structural optimization involving the selection of preferred nodes (or PNs) with specific local characteristics (such as the number of input variables, the order of the polynomial, and a collection of the specific subset of input variables) and addresses specific aspects of parametric optimization. An aggregate performance index with a weighting factor is proposed in order to achieve a sound balance between approximation and generalization (predictive) abilities of the network. To evaluate the performance of the GA-based SOPNN, the model is experimented with using chaotic time series data. A comparative analysis reveals that the proposed GA-based SOPNN exhibits higher accuracy and superb predictive capability in comparison to some previous models available in the literature.  相似文献   
79.
基于网络的资源已成企业构建竞争优势的重要组成部分。本文基于企业资源理论和网络理论,对中国沪、深两地上市的81家制药企业的研发网络与企业绩效关系进行了实证分析。研究表明,企业网络规模以及企业网络中的异质性资源均对企业绩效产生了正面影响。本研究结论还证实了习得能力是企业网络资源向企业绩效转化的中间机制。  相似文献   
80.
Social media is growing rapidly. Providing both risks and opportunities for organizations as it does. The social strategy cone is developed for evaluating social media strategies. This framework comprises of seven key elements of social media strategies as based on a systematic literature review and case studies. The results of 21 interviews have contributed to the construction of the social media strategy cone for analyzing social media strategies. Three levels of maturity of social media strategy are proposed: initiation, diffusion and maturity. Initiation includes the key elements: ‘target audience’ and ‘channel choice’ while all case organizations studied payed attention to these elements. Diffusion includes the elements: ‘goals’, ‘resources’ and ‘policies’. Maturity adds the elements of ‘monitoring’ and ‘content activities’. Only 3 of the 9 organizations studied are in this phase of maturity. Although, theory suggests the importance of the element of ‘monitoring’ our research shows the need for more attention in practice.  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