全文获取类型
收费全文 | 39177篇 |
免费 | 499篇 |
国内免费 | 654篇 |
专业分类
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 |
出版年
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.
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.
984.
985.
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.
Diego Reforgiato Recupero 《Information Retrieval》2007,10(6):563-579
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.
相似文献
Diego Reforgiato RecuperoEmail: |
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.
相似文献
Haym HirshEmail: |
988.
Result merging methods in distributed information retrieval with overlapping databases 总被引:5,自引:0,他引:5
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.
相似文献
Sally McCleanEmail: |
989.
Brian Edward Hubner 《Archival Science》2007,7(3):195-206
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 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
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.
Beatrice S. Bartlett 《Archival Science》2007,7(4):369-390
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.
相似文献
Beatrice S. BartlettEmail: |