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   10621篇
  免费   97篇
  国内免费   9篇
教育   7175篇
科学研究   1369篇
各国文化   128篇
体育   727篇
综合类   5篇
文化理论   96篇
信息传播   1227篇
  2020年   106篇
  2019年   163篇
  2018年   183篇
  2017年   223篇
  2016年   194篇
  2015年   133篇
  2014年   196篇
  2013年   2097篇
  2012年   184篇
  2011年   173篇
  2010年   148篇
  2009年   165篇
  2008年   197篇
  2007年   188篇
  2006年   175篇
  2005年   153篇
  2004年   140篇
  2003年   130篇
  2002年   119篇
  2001年   132篇
  2000年   154篇
  1999年   133篇
  1998年   88篇
  1997年   88篇
  1996年   97篇
  1995年   83篇
  1994年   104篇
  1993年   112篇
  1992年   148篇
  1991年   153篇
  1990年   156篇
  1989年   155篇
  1988年   131篇
  1987年   142篇
  1986年   150篇
  1985年   167篇
  1984年   159篇
  1983年   156篇
  1982年   121篇
  1981年   133篇
  1980年   111篇
  1979年   151篇
  1978年   155篇
  1977年   109篇
  1976年   108篇
  1975年   104篇
  1974年   84篇
  1973年   103篇
  1972年   88篇
  1970年   84篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
61.
62.
A brief commentary from the Museum Association of New York (MANY) on the unprecedented gap posed by baby-boomer retirement. Based, in part, on MANY's white paper, “Who's Next? Questioning the Future of Museum Leadership in New York State,” this essay deals with questions of succession, leadership and general differences in New York's museum community.  相似文献   
63.
Editorial     
This issue of the Journal contains three interesting articlesabout central aspects of public opinion research, as well asan equal number of research notes that reflect the range oftopics that interest all public opinion researchers. Toshio Takeshita takes a turn at reconceptualizing agenda-settingstudies, using a taxonomy  相似文献   
64.
An account is given of the effects of the EU Copyright Directive on the working of the library of a learned society and the changes in practices required to conform with it.  相似文献   
65.
In this essay, we respond to the narratives and essays in this issue by examining organizational power issues related to researchers and institutional research boards (IRBs). Rather than taking a singular perspective on power, we use multiple perspectives and suggest that the cumulative analyses provide the best understanding of IRBs and organizational power.  相似文献   
66.
Analysis of Statistical Question Classification for Fact-Based Questions   总被引:1,自引:0,他引:1  
Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome.  相似文献   
67.
68.
ABSTRACT

Control of relative humidity (RH) for collections care is challenging in U.K. historic houses because they are often highly ventilated with poor heat retention, a porous building fabric and naturally tend to high (60–80%) RH if unheated. The significance of the building means that large-scale modifications and installation of air handling systems may be unfeasible and undesirable for the conservation of the building. In the late 1980s the National Trust, for English, Wales and Northern Ireland, investigated conservation heating as an RH control method that works with the natural environment of historic buildings, mimicking historic heating and requiring only modification of existing heating services or a light touch installation of new heating systems. The National Trust adopted conservation heating as its preferred method for environmental control in historic buildings from the 1990s. This method was presented at the IIC 1994 Ottawa congress on preventive conservation. Conservation heating has since been adopted by many historic house management organisations, particularly across north-west Europe, where it is well suited to the climate. This paper reviews conservation heating developments implemented by the National Trust since 1994, in response to a changing external context, new knowledge and developments in operational practice.  相似文献   
69.
70.
What If?     
  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