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   39177篇
  免费   499篇
  国内免费   654篇
教育   26236篇
科学研究   5676篇
各国文化   86篇
体育   2358篇
综合类   1808篇
文化理论   438篇
信息传播   3728篇
  2024年   15篇
  2023年   50篇
  2022年   331篇
  2021年   763篇
  2020年   549篇
  2019年   387篇
  2018年   2437篇
  2017年   2393篇
  2016年   1876篇
  2015年   1046篇
  2014年   1553篇
  2013年   2033篇
  2012年   2430篇
  2011年   3147篇
  2010年   3081篇
  2009年   2492篇
  2008年   2790篇
  2007年   3155篇
  2006年   2095篇
  2005年   1960篇
  2004年   1446篇
  2003年   1232篇
  2002年   937篇
  2001年   760篇
  2000年   438篇
  1999年   276篇
  1998年   159篇
  1997年   113篇
  1996年   90篇
  1995年   76篇
  1994年   49篇
  1993年   46篇
  1992年   46篇
  1991年   33篇
  1990年   9篇
  1989年   5篇
  1988年   3篇
  1987年   4篇
  1986年   7篇
  1985年   4篇
  1984年   1篇
  1983年   3篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   3篇
  1976年   1篇
  1957年   2篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
就社会环境和系统环境2个层面尝试性地分析农业科普期刊的出版环境,并提出以全面纳入公益性事业管理体制(公益型)、划属科协机构主管(半公益型)、寻求体制外战略合作(经营型)等3种方式实现农业科普期刊可持续发展的探讨性意见.  相似文献   
982.
随着计算机和互联网的普及,作者以软(光)盘和电子邮件的形式向出版社交电子稿的情况越来越普遍.相对于手写稿而言,电子稿件文字整洁,内容清晰,成稿快捷,具有方便审稿校对、缩短出版周期等优点.  相似文献   
983.
通过对美国SCI、Ei、MEDLINE、CA 等4种国际著名检索系统收录评价体系及我国高校学报被这4种国际著名检索系统收录情况的分析,认为我国高校学报应从提高学术质量、提升刊物的国际化程度、强化期刊的编排出版规范、缩短出版周期、注意英文写作规范、重视引文分析数据、加强对国际检索机构进行有针对性的宣传并与之动态联系等几方面入手,方能提高被国际著名检索系统收录的可能性.  相似文献   
984.
黄钺  李燕 《出版科学》2007,15(2):36-38
每本时尚期刊都有其特有的市场定位及风格特征,这直接影响和制约着刊物的设计面貌.期刊的版式设计是为了更好地突出期刊的定位和风格,使刊物在美观基础上更快更好地传递信息.本文通过案例分析阐述了时尚期刊编排的一些方法和规律.  相似文献   
985.
严红 《出版科学》2007,15(6):52-54,27
在网络技术高速发展、互联网迅速普及的背景下,网络写手作为新生事物发展速度惊人,影响力不可小觑.本文探讨了网络写手的产生过程与原因、类型与特点、影响与规范等方面的问题.  相似文献   
986.
Text document clustering provides an effective and intuitive navigation mechanism to organize a large amount of retrieval results by grouping documents in a small number of meaningful classes. Many well-known methods of text clustering make use of a long list of words as vector space which is often unsatisfactory for a couple of reasons: first, it keeps the dimensionality of the data very high, and second, it ignores important relationships between terms like synonyms or antonyms. Our unsupervised method solves both problems by using ANNIE and WordNet lexical categories and WordNet ontology in order to create a well structured document vector space whose low dimensionality allows common clustering algorithms to perform well. For the clustering step we have chosen the bisecting k-means and the Multipole tree, a modified version of the Antipole tree data structure for, respectively, their accuracy and speed.
Diego Reforgiato RecuperoEmail:
  相似文献   
987.
Intelligent use of the many diverse forms of data available on the Internet requires new tools for managing and manipulating heterogeneous forms of information. This paper uses WHIRL, an extension of relational databases that can manipulate textual data using statistical similarity measures developed by the information retrieval community. We show that although WHIRL is designed for more general similarity-based reasoning tasks, it is competitive with mature systems designed explicitly for inductive classification. In particular, WHIRL is well suited for combining different sources of knowledge in the classification process. We show on a diverse set of tasks that the use of appropriate sets of unlabeled background knowledge often decreases error rates, particularly if the number of examples or the size of the strings in the training set is small. This is especially useful when labeling text is a labor-intensive job and when there is a large amount of information available about a particular problem on the World Wide Web.
Haym HirshEmail:
  相似文献   
988.
In distributed information retrieval systems, document overlaps occur frequently among different component databases. This paper presents an experimental investigation and evaluation of a group of result merging methods including the shadow document method and the multi-evidence method in the environment of overlapping databases. We assume, with the exception of resultant document lists (either with rankings or scores), no extra information about retrieval servers and text databases is available, which is the usual case for many applications on the Internet and the Web. The experimental results show that the shadow document method and the multi-evidence method are the two best methods when overlap is high, while Round-robin is the best for low overlap. The experiments also show that [0,1] linear normalization is a better option than linear regression normalization for result merging in a heterogeneous environment.
Sally McCleanEmail:
  相似文献   
989.
Census information of some form has been collected in Canada since the 1611 census of New France. Aboriginal people, identified or not, have been included in these enumerations. The collection of this information has had a profound impact on Aboriginal people and has been an element that has shaped their relationship with the dominant society. In response, Canadian Aboriginal people have often resisted and refused to co-operate with census takers and their masters. This article is an examination of this phenomenon focused on the censuses conducted in the post-Confederation period to the present. A census is made to collect information on populations and individuals that can then be used to configure and shape social and political relations between those being enumerated and the creators of the census. However, the human objects of the census are not just passive integers and they have resisted its creation in a number of ways, including being “missing” when the census is taken, refusing to answer the questions posed by enumerators or even driving them off Aboriginal territory. A census identifies elements of the social order and attempts to set them in their “proper” place and those who do not wish to be part of that order may refuse to take part. Archivists and historians must understand that the knowledge gained in a census is bound with the conditions of own creation. This has been noted by contemporary Aboriginal researchers who often state that the archival record of their people often distorts history and reflects the ideas and superficial observations of their Euro-Canadian creators. Changes to the Census of Canada since 1981, have increased the participation rate and therefore changed the nature of the record.
Brian Edward HubnerEmail:

Brian Edward Hubner   is currently Acquisition and Access Archivist at the University of Manitoba Archives & Special Collections. He was previously employed at the Archives of Manitoba, in Government Records; Queen’s University Archives, Kingston; and at the National Archives of Canada, Ottawa. He has a Master of Arts (History, in Archival Studies) from the University of Manitoba, and a Master of Arts (History), from the University of Saskatchewan. The 2nd edition of Brian’s co-authored book on the history of the Cypress Hills of Saskatchewan and Alberta is being published in 2007. He has published articles and delivered conference papers on Canadian Aboriginal peoples including “Horse Stealing and the Borderline: The N.W.M.P. and the Control of Indian Movement, 1874-1900.” His current research interest focuses on relationship between Canada’s Aboriginal Peoples and Canadian archives. Brian is married and has two children.  相似文献   
990.
This article describes the first half century of the Communist government’s supervision and management of the central-government archives of the last two dynasties. Immediately with the Communist ascent to power in 1949, the new government took great interest in assembling and protecting the country’s archival documents, readying the Ming-Qing archives for access to scholars, and preparing for publication of selected materials. By the 1980s Beijing’s Number One Historical Archives, in charge of the largest holding of Ming-Qing documents, had become the first Chinese authority to complete a full sorting and preliminary catalogues for such a collection. Moreover, to facilitate searches, an attempt has recently begun to create a subject-heading system for these and other holdings in the country. In the first half century’s final decades, foreign researchers were admitted for the first time and tours and international exchanges began to take place.
Beatrice S. BartlettEmail:
  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