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   38907篇
  免费   753篇
  国内免费   1066篇
教育   23248篇
科学研究   7967篇
各国文化   130篇
体育   3226篇
综合类   2236篇
文化理论   93篇
信息传播   3826篇
  2024年   22篇
  2023年   150篇
  2022年   443篇
  2021年   713篇
  2020年   975篇
  2019年   883篇
  2018年   857篇
  2017年   822篇
  2016年   994篇
  2015年   1214篇
  2014年   2784篇
  2013年   3528篇
  2012年   3432篇
  2011年   3456篇
  2010年   2427篇
  2009年   2361篇
  2008年   2386篇
  2007年   2560篇
  2006年   2419篇
  2005年   2008篇
  2004年   1656篇
  2003年   1376篇
  2002年   998篇
  2001年   776篇
  2000年   503篇
  1999年   237篇
  1998年   157篇
  1997年   128篇
  1996年   72篇
  1995年   68篇
  1994年   74篇
  1993年   60篇
  1992年   50篇
  1991年   46篇
  1990年   14篇
  1989年   46篇
  1988年   5篇
  1985年   3篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
  1981年   2篇
  1979年   1篇
  1978年   5篇
  1977年   1篇
  1976年   2篇
  1957年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
This article presents the intervention process carried out on a work of art created by artist Yolanda Gutiérrez Acosta, using a series of ephemeral materials such as butterfly wings and agave thorns. The work, an installation from 2002, is entitled ‘Efímeras’ (‘Ephemera’) and consists of 12 flowers mounted on acetate sheets and attached to the same with vinyl acetate copolymers and acrylic acid esters (Mowilith®). These flowers are installed on the floor in a bed of dried flowers. The conservation of contemporary art can lead to some previously unimaginable problems for restorers. Current works of art are somewhat material in nature, but they also have a conceptual dimension that is essential for their artistic interpretation. The artist’s participation in the decision-making process prior to the restoration was quite useful. The passage of time, its effect on the work, and the need to understand the possibility of the demise and destruction of the work were implicit as of the onset of its creation, such that, according to the artist, we are forced to reflect upon the possibilities of its future state.  相似文献   
82.
This research analyzed a dataset of academic libraries' posts on Facebook. It applied a text and data analytics approach to a dataset collected from the Facebook posts of academic libraries at the top 100 English-speaking universities, as listed by the 2014 Shanghai World University Rankings. The dataset is from a two-year posting history of 18,333 unique posts, 113,621 likes, and 3401 comments. Less than a quarter of the libraries had more than 2000 post-related likes, and only seven received more than 100 comments on their postings. Content analysis identified the most prevalent single word (unigrams), bigrams (two-word sequences), and trigrams (three-word sequences) in high and low engagement content. Semantic analysis identified the semantic categories for posts with high and low engagement. The findings can assist academic libraries in their social media strategies for engagement, marketing, and visibility.  相似文献   
83.
This paper analyses the publication patterns of researchers in the field of applied sciences at Universities of Technology in South Africa. Aspects investigated include publications in SCOPUS-listed journals; number of citations and countries of publication. Collaborative research patterns at national and international levels were also investigated. A bibliometric analysis approach was followed using SCOPUS as the main source of data and analysing the articles published in selected applied science disciplines. Results show that researchers in the field of applied sciences in universities of technology have increased their number of publications over the past 10?years and are also working in conjunction with other researchers both nationally and internationally. The analysis is an important addition to the field in South Africa which helps in measuring how institutions are positively responding to government incentives in research. The results are also important to information professionals who are increasingly playing an important role in research impact assessments.  相似文献   
84.
[目的/意义]整体把握馆际互借和文献传递发展脉络,探索馆际互借和文献传递的未来发展趋势。[方法/过程]以WoS核心合集作为统计源,采用文献计量学方法对国外馆际互借与文献传递研究文献的发文时间、国家与地区、机构与作者、发表刊物等进行统计分析;利用HisCite和CiteSpace筛选出重要相关文献,在对其进行阅读归纳的基础上,进行馆际互借研究的发展脉胳与主题分析。[结果/结论]馆际互借可分为传统馆际互借时期(20世纪80年代以前)、馆际互借研究迅速发展期(1980-1990年)、文献传递快速上升期(1990-2000年)、动态发展期(2000-2016年)4个阶段,未来馆际互借员角色应更加多样化。  相似文献   
85.
[目的/意义]探讨如何从大量论文中快速发现相关论文,研究论文主题创新的方法,为研究者阅读和利用期刊论文提供参考。[方法/过程]在对论文主题创新和自引网络概念界定的基础上,提出研究论文主题创新的思路、方法和工具。以美国印第安纳大学在图书情报学领域的论文为例进行实证研究。[结果/结论]利用主路径分析可以快速从自引网络中发现由于引用而产生联系的论文,在此基础上可以进行主题创新分析。  相似文献   
86.
In 2008 Meier and Conkling first tested Google Scholar's coverage of the engineering literature against citations gathered from the Compendex database. Since that time, other studies have used the same methodology and found improvement in Google Scholar's coverage. This study uses engineering dissertations from Proquest Dissertations & Theses to create a data set of citations for the comparison of fee-based databases, Compendex and Scopus, against Google Scholar. From 1950 to 2017 Google Scholar outperformed both Compendex and Scopus in discoverability of citations in nine engineering subjects. These results have implications for collection management and information literacy program planning for librarians.  相似文献   
87.
We evaluate author impact indicators and ranking algorithms on two publication databases using large test data sets of well-established researchers. The test data consists of (1) ACM fellowship and (2) various life-time achievement awards. We also evaluate different approaches of dividing credit of papers among co-authors and analyse the impact of self-citations. Furthermore, we evaluate different graph normalisation approaches for when PageRank is computed on author citation graphs.We find that PageRank outperforms citation counts in identifying well-established researchers. This holds true when PageRank is computed on author citation graphs but also when PageRank is computed on paper graphs and paper scores are divided among co-authors. In general, the best results are obtained when co-authors receive an equal share of a paper's score, independent of which impact indicator is used to compute paper scores. The results also show that removing author self-citations improves the results of most ranking metrics. Lastly, we find that it is more important to personalise the PageRank algorithm appropriately on the paper level than deciding whether to include or exclude self-citations. However, on the author level, we find that author graph normalisation is more important than personalisation.  相似文献   
88.
Scientific research is increasingly relying on collaborations to address complex real-world problems. Many researchers, policymakers, and administrators consider a multidisciplinary environment an important factor for fostering research collaborations, especially interdisciplinary ones that involve researchers from different disciplines. However, it remains unknown whether a higher level of multidisciplinarity within an academic institution is associated with internal collaborations that are more prevalent and more interdisciplinary. Analyzing 90,000 publications by 2500 faculty members in over 100 academic institutions from three multidisciplinary areas, information, public policy, and neuroscience, we investigated the connection between multidisciplinarity and research collaborations. Based on social network analysis and text mining, our analysis suggests that more multidisciplinary institutions are not necessarily more collaborative, although they do feature collaborations that are more interdisciplinary. Our findings provide implications for academic administrators and policymakers to promote research collaborations and interdisciplinarity in academic institutions.  相似文献   
89.
Placing Facebook     
Facebook is challenging professional journalism. These challenges were evident in three incidents from 2016: the allegation that Facebook privileged progressive-leaning news on its trending feature; Facebook’s removal of the Pulitzer Prize-winning “Napalm Girl” photo from the pages of prominent users; and the proliferation of “fake news” during the US presidential election. Using theoretical concepts from the field of boundary work, this paper examines how The Guardian, The New York Times, Columbia Journalism Review and Poynter editorialized Facebook’s role in these three incidents to discursively construct the boundary between the value of professional journalism to democracy and Facebook’s ascendant role in facilitating essential democratic functions. Findings reveal that these publications attempted to define Facebook as a news organization (i.e., include it within the boundaries of journalism) so that they could then criticize the company for not following duties traditionally incumbent upon news organizations (i.e., place it outside the boundaries of journalism). This paper advances scholarship that focuses on both inward and outward conceptions of boundary work, further explores the complex challenge of defining who a journalist is in the face of rapidly changing technological norms, and advances scholarship in the field of media ethics that positions ethical analysis at the institutional level.  相似文献   
90.
广告效果下降是当前广告业的一种普遍现象,成为困扰广告商和广告公司的一个难题。如何创制更有新意、更有效果的广告,使广告传递的商品信息让受众注意、形成记忆、产生行动是广告人努力的方向。本文通过时广告效果下降原因的剖析,提出了相应的对策和措施。  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