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   1508篇
  免费   13篇
  国内免费   1篇
教育   1112篇
科学研究   83篇
各国文化   14篇
体育   134篇
文化理论   24篇
信息传播   155篇
  2021年   13篇
  2020年   24篇
  2019年   33篇
  2018年   40篇
  2017年   44篇
  2016年   53篇
  2015年   23篇
  2014年   32篇
  2013年   365篇
  2012年   46篇
  2011年   40篇
  2010年   29篇
  2009年   27篇
  2008年   39篇
  2007年   39篇
  2006年   34篇
  2005年   36篇
  2004年   35篇
  2003年   27篇
  2002年   33篇
  2001年   22篇
  2000年   24篇
  1999年   24篇
  1998年   13篇
  1997年   23篇
  1996年   15篇
  1995年   17篇
  1994年   17篇
  1993年   22篇
  1992年   15篇
  1991年   32篇
  1990年   10篇
  1989年   11篇
  1988年   21篇
  1987年   16篇
  1986年   12篇
  1985年   15篇
  1984年   11篇
  1983年   12篇
  1982年   13篇
  1981年   19篇
  1980年   13篇
  1979年   15篇
  1978年   15篇
  1977年   13篇
  1976年   16篇
  1975年   11篇
  1974年   9篇
  1969年   7篇
  1967年   6篇
排序方式: 共有1522条查询结果,搜索用时 15 毫秒
871.
In this research, we performed radiographic experiments exploiting polychromatic phase-contrast imaging, a method for contrast enhancement in transmitted neutron beams by measuring a sample made with a homogeneous material but exhibiting a different microstructure induced by mechanical actions. We were able to reveal the armourers’ marks now obscured by polishing that are present in these examples of medieval armour.  相似文献   
872.
873.
Journal clubs are an effective means to increase skills in handling evidence and support the continuing professional development of library and knowledge services workers. This editorial examines the progression of HILJ Club, an online journal club, from an idea to the launch of a dedicated platform. One article is selected per issue of the Health Information and Libraries Journal with an open discussion invited following a brief summary and reflections by a host. Participation in HILJ Club is growing. Future success is reliant on wider engagement, and an invitation is extended to join in the discussions or even host an edition.  相似文献   
874.
An automatic method for correcting spelling and typing errors from teletypewriter keyboard input is proposed. The computerized correcting process is presented as a heuristic tree search. The correct spellings are stored character-by-character in a psuedo-binary tree. The search examines a small subset of the database (selected branches of the tree) while checking for insertion, substitution, deletion and transposition errors. The correction procedure utilizes the inherent redundancy of natural language. Multiple errors can be handled if at least two correct characters appear between errors. Test results indicate that this approach has the highest error correction accuracy to date.  相似文献   
875.
This paper aims to identify the strategic motivators and expected benefits related to the implementation of e-commerce infrastructures in traditional “brick and mortar” organisations. Despite the fact that the clearest benefit from e-commerce might be expected to come from contribution to corporate profits, either from an increase of sales or reduction of costs, but this may not be the case. The literature suggests that there are different ways in which the potential benefits can be assessed. These ways are directly related to the evolution of e-commerce. This research has chosen six representative organisations from different sectors to explore their rationales for their e-commerce strategies. One of the main benefits reported is to increase the focus on the customer and improving internal communications. Additionally, obtaining competitive advantage was found to be a powerful motivator, despite the fact that the recent academic literature suggests that this is very difficult to achieve.  相似文献   
876.
诺贝尔奖得主寄语中国未来的科学发展   总被引:1,自引:0,他引:1       下载免费PDF全文
5月25—26日,在纪念国家自然科学基金委员会成立20周年的“21世纪科学前沿与中国的机遇”高层论坛上,6位诺贝尔奖得主做了精彩报告。在对中国科学的未来发展寄予殷切期望的同时,他们也对中国的科技政策提出了具有启发性的建议。现摘编如下:诺贝尔化学奖得主、美国耶鲁大学教授S  相似文献   
877.
878.
Statistical inference relies heavily on the concept of sampling distributions. However, sampling distributions are difficult to teach. We present a series of short animations that are story‐based, with associated assessments. We hope that our contribution can be useful as a tool to teach sampling distributions in the introductory statistics classroom.  相似文献   
879.
Psychologists working in education in Aotearoa/New Zealand work in diverse educational environments making day-to-day decisions informed by evidence-based practice. As a relatively small professional group with a complex work programme, they contribute to the assessments and decision-making processes of children and young people across multiple settings. This paper explores the results of a small-scale national survey of psychologists working in education through the Ministry of Education. Results showed that these psychologists use at least 25 assessment methods including assessments within behavioural, emotional, social, and cognitive domains. The assessment data are used for three primary reasons: to understand the child, inform decision-making, and contribute to discussions around appropriate interventions. The use of interviews, observation and collaboration were identified as key to their assessment practices, illustrating a preference towards more dialogic and ecological ways of working. While the majority used assessment practices that align with facilitating the learning of the child across contexts, the psychologists reported that ethical dilemmas arose when they were expected to be more diagnostic in their focus.  相似文献   
880.
As an information medium, video offers many possible retrieval and browsing modalities, far more than text, image or audio. Some of these, like searching the text of the spoken dialogue, are well developed, others like keyframe browsing tools are in their infancy, and others not yet technically achievable. For those modalities for browsing and retrieval which we cannot yet achieve we can only speculate as to how useful they will actually be, but we do not know for sure. In our work we have created a system to support multiple modalities for video browsing and retrieval including text search through the spoken dialogue, image matching against shot keyframes and object matching against segmented video objects. For the last of these, automatic segmentation and tracking of video objects is a computationally demanding problem which is not yet solved for generic natural video material, and when it is then it is expected to open up possibilities for user interaction with objects in video, including searching and browsing. In this paper we achieve object segmentation by working in a closed domain of animated cartoons. We describe an interactive user experiment on a medium-sized corpus of video where we were able to measure users’ use of video objects versus other modes of retrieval during multiple-iteration searching. Results of this experiment show that although object searching is used far less than text searching in the first iteration of a user’s search it is a popular and useful search type once an initial set of relevant shots have been found.  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