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   1969篇
  免费   37篇
教育   1359篇
科学研究   155篇
各国文化   29篇
体育   296篇
综合类   1篇
文化理论   34篇
信息传播   132篇
  2023年   14篇
  2022年   30篇
  2021年   51篇
  2020年   105篇
  2019年   155篇
  2018年   178篇
  2017年   183篇
  2016年   131篇
  2015年   82篇
  2014年   94篇
  2013年   411篇
  2012年   80篇
  2011年   71篇
  2010年   32篇
  2009年   40篇
  2008年   30篇
  2007年   32篇
  2006年   24篇
  2005年   19篇
  2004年   23篇
  2003年   27篇
  2002年   16篇
  2001年   20篇
  2000年   14篇
  1999年   8篇
  1998年   10篇
  1997年   10篇
  1996年   4篇
  1995年   16篇
  1994年   9篇
  1993年   6篇
  1992年   9篇
  1991年   5篇
  1990年   6篇
  1989年   5篇
  1988年   5篇
  1987年   5篇
  1985年   6篇
  1984年   3篇
  1982年   2篇
  1981年   6篇
  1978年   3篇
  1977年   4篇
  1976年   5篇
  1972年   3篇
  1970年   2篇
  1966年   1篇
  1955年   1篇
  1948年   1篇
  1830年   1篇
排序方式: 共有2006条查询结果,搜索用时 62 毫秒
1.
2.
ABSTRACT

This paper aims to analyse the initiatives undertaken by some immigrant communities residing in Latin America to record their mobilisation around the First World War. After the armistice, European communities in Argentina, Bolivia, Brazil, Chile, Mexico, Paraguay, Peru, Uruguay and other countries gathered detailed information about their activities during the conflict, published as profusely illustrated books of remembrance, offered to their governments as proof of their loyalty. The article intends to establish the peculiar nature of these publications as records of the war effort, and analyse the agents and processes of their elaboration, and their role as commemorative but also as archival documents.  相似文献   
3.
4.
Portugal, as a small and increasingly integrated European economy, has been influenced by some of the major trends that defined the agenda of higher education policy in recent decades. Its backwardness – notably in terms of skills, education, and training – has frequently prompted a focus of attention on its international counterparts, particularly those in Europe, in search of affinities, solutions and errors to avoid. The search for guidance has also created an opportunity for the intervention of international organisations. Until Portugal joined the European Union (EU) in 1986, the Organisation for Economic Cooperation and Development (OECD) and the World Bank were the main agencies playing this role. Henceforth, those institutions lost some influence, and the European dimension gained increasing prominence. This article discusses the role of those international organisations in the definition of priorities for Portuguese higher education policy in recent decades, and provides a general overview of the outside perceptions of the Portuguese situation as understood by these international organisations. In particular, the article focuses on those interventions that promoted the influence of market mechanisms in the Portuguese higher education system by emphasising the need for higher education institutions (HEIs) to strive for increased economic responsiveness.  相似文献   
5.
This article presents an empirical study focused on a qualitative analysis of the UNIMARC format. An analysis of the structural quality of the data provided by the format is evaluated to determine its current suitability for meeting the requirements and trends in data architecture for the information network and the Semantic Web. Driven by a set of quality characteristics that identify weaknesses in the data schema that cannot be bridged by simply converting data to MARC XML or RDF/XML, we conclude that the UNIMARC format is not compliant with the current metadata schema desiderata and must be replaced.  相似文献   
6.
This study examined whether persuasive health messages embedded in shooter games have broad or targeted effects on players’ willingness to engage in risk behaviors (N = 145). Participants presented with in-game health messages discouraging alcohol-impaired driving of motor vehicles showed reduced willingness to drink alcohol and to operate both motor and nonmotor vehicles, compared to those in a no-message gaming control condition. There were no spillover effects on willingness to smoke cigarettes or marijuana, thus implying targeted persuasive effects. In addition, players experiencing high instead of low cognitive load showed decreased postexperiment willingness to drink and operate nonmotor vehicles, thus suggesting that playing a game under high cognitive load can influence players’ attitudes. The findings replicate previous research and further expand on knowledge-activation and thought-disruption mechanisms underlying the persuasiveness of health messages.  相似文献   
7.
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
8.
9.
ABSTRACT

The aim of the present study was to investigate the existence of a relative age effect (RAE) on physical fitness of preschoolers. Anthropometry and physical fitness were assessed in 3147 children (3–5 years old) using the PREFIT battery. Based on the birth year, participants were divided into 3year groups (3-, 4- and 5-years). Within each year group, 4quarter groups were created: quarter 1, preschoolers born from January to March; quarter 2, from April to June; quarter 3, from July to September; quarter 4, from October to December. The MANCOVA analysis revealed a main effect of year group (Wilks’ λ = 0.383; F10,5996 = 369.64; p < 0.001, ηp 2 = 0.381) and of quarter (Wilks’ λ = 0.874; F15,8276.6 = 27.67; p < 0.001; ηp 2 = 0.044) over the whole battery of tests. To the best of our knowledge, this is the first study to report the existence of RAE at the preschool stage. In general, performance improved as the relative age increased (i.e., those born in quarter 1 performed better than those in the other quarters). Individualization strategies should be addressed within the same academic year not only in elementary or secondary years but also in preschoolers.  相似文献   
10.
ABSTRACT

The objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (< .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes.  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