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   13766篇
  免费   188篇
  国内免费   26篇
教育   9267篇
科学研究   1656篇
各国文化   350篇
体育   1025篇
综合类   10篇
文化理论   95篇
信息传播   1577篇
  2021年   125篇
  2020年   201篇
  2019年   283篇
  2018年   361篇
  2017年   418篇
  2016年   360篇
  2015年   252篇
  2014年   327篇
  2013年   2331篇
  2012年   305篇
  2011年   313篇
  2010年   283篇
  2009年   266篇
  2008年   337篇
  2007年   337篇
  2006年   266篇
  2005年   228篇
  2004年   263篇
  2003年   193篇
  2002年   171篇
  2001年   240篇
  2000年   295篇
  1999年   233篇
  1998年   152篇
  1997年   141篇
  1996年   134篇
  1995年   108篇
  1994年   111篇
  1993年   113篇
  1992年   200篇
  1991年   209篇
  1990年   202篇
  1989年   210篇
  1988年   184篇
  1987年   170篇
  1986年   190篇
  1985年   222篇
  1984年   180篇
  1983年   183篇
  1982年   149篇
  1981年   120篇
  1980年   118篇
  1979年   187篇
  1978年   136篇
  1977年   126篇
  1976年   115篇
  1975年   104篇
  1974年   119篇
  1973年   111篇
  1971年   100篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
In Experiment 1, two groups of female rats were trained in a triangular pool to find a hidden platform whose location was defined in terms of a single a landmark, a cylinder outside the pool. For one group, the landmark had only a single pattern (i.e., it looked the same when approached from any direction), while for the other, the landmark contained four different patterns (i.e., it looked different when approached from different directions). The first group learned to swim to the platform more rapidly than the second. Experiment 2 confirmed this difference when female rats were trained in a circular pool but found that male rats learned equally rapidly (and as rapidly as females trained with the single-pattern landmark) with both landmarks. This second finding was confirmed in Experiment 3. Finally, in Experiment 4a and 4b, male and female rats were trained either with the same, single-pattern landmark on all trials or with a different landmark each day. Males learned equally rapidly (and as rapidly as females trained with the unchanged landmark) whether the landmark changed or not. We conclude that male and female rats learn rather different things about the landmark that signals the location of the platform.  相似文献   
992.
From the beginning of the 1990s, different types of quality management and evaluation systems have become integrated into higher education institutes throughout Europe due to the creation of the European Higher Education Area (EHEA). This has meant that the university libraries have had to learn how to evaluate their services and improve their quality. Quality audits are one tool that can be used in quality management approaches to assess how well an organization is being managed. This paper describes and benchmarks the use of external and internal auditing in three European academic libraries, i.e. the Medical Library of the University Medical Center Hamburg-Eppendorf (Germany), the Universitat Autònoma de Barcelona Library (Spain) and the University of Eastern Finland Library (Finland). The results reveal the best practices of auditing in these institutions; and recommendations are provided for the further development of library auditing and ways to improve co-operation between libraries.  相似文献   
993.
Information warfare is viewed as a social-information phenomenon in today’s world. Particular features of information warfare pursued in World 2.0 are defined. The emphasis is made on the role of a humanitarian tool, the information culture, which allows one to counter information warfare. The personal information culture and information culture of a society are defined. The importance of the development of the information culture in the higher education area is discussed.  相似文献   
994.
This paper considers the properties of using the multidimensional approach in the information support of scientific research on ethnology and historical anthropology based on the information resources of the Institute of Scientific Information on Social Sciences (INION). The principles of the content processing of documents and queries based on a complex of linguistic tools of the Automated Information System on Social Sciences (AISON) are considered. The problems of increasing the professional competence and level of information culture of consumers who search for ethnological information by queries of different complexities are discussed.  相似文献   
995.
To date, there is no unique accepted and standardized method for identifying journal articles, authors, and other elements of bibliographic metadata, although in recent years a considerable number of identifiers have been developed. The problem of identification becomes particularly urgent when the same information is used in different scientometric and bibliographic databases, when it is necessary to carry out complex data processing with their further integration. The need for unique identifiers outside of a system is a universal requirement. Initiatives to construct identifiers and systems appear regularly in the scientific press; however, they have not achieved the necessary degree of interoperability. This paper presents the general problems that are associated with metadata identifiers of scientific publications, analyzes a number of the existing systems and technologies, and indicates the current initiatives to remove the gap in the area of identification.  相似文献   
996.
997.
998.
Open access (OA) literature is digital, online, free of charge, and free of most copyright and licensing restrictions. The lack of clarity of publisher permissions for archiving in OA repositories affects the adoption of the green OA route. This paper explores editorial policies and self‐archiving conditions in 1,615 Spanish scholarly journals. 48% are published by university and research institutions, 25% by associations/societies, and 17% by commercial publishers; social sciences and humanities (SSH) accounted for 67% of the journals (44.5% and 22.5%, respectively) followed by health sciences (20%); 71% offered gratis access immediately after publication, and 11% after an embargo; 31% provided some mention of author rights. Self‐archiving was specifically allowed by 65% of the journals; 52% were classified as ROMEO‐blue, 12% as green and 15% as white, and 21% could not be classified; 21%, mostly in SSH, used some type of Creative Commons license.  相似文献   
999.
This article describes a half-day preconference that focused on the library as publisher. It examined how the movement from print to online publication has impacted the roles of libraries and their ability to take on new roles as publishers. The session explored the benefits of libraries becoming publishers, and discussed Open Access, what it is and is not and its importance to libraries and scholarly communication. A detailed case study of the publishing operations of the University Library System at the University of Pittsburgh was presented as an example of a successful library publishing program. The session provided an opportunity for participants to discover ways that libraries can be involved in publishing.  相似文献   
1000.
依据国际数据管理协会数据管理知识体系(DMBOK)中的数据质量管理过程,分析了电动汽车多源信息 决策支持系统中的数据特点以及建设中存在的问题,提出改进建议,并初步构建适用于电动汽车多源信息决策支持系 统的数据质量管理流程。  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