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   13955篇
  免费   183篇
  国内免费   7篇
教育   10197篇
科学研究   1208篇
各国文化   80篇
体育   1113篇
综合类   7篇
文化理论   86篇
信息传播   1454篇
  2021年   102篇
  2020年   154篇
  2019年   253篇
  2018年   350篇
  2017年   359篇
  2016年   328篇
  2015年   201篇
  2014年   279篇
  2013年   2582篇
  2012年   297篇
  2011年   361篇
  2010年   223篇
  2009年   216篇
  2008年   322篇
  2007年   232篇
  2006年   301篇
  2005年   198篇
  2004年   183篇
  2003年   175篇
  2002年   214篇
  2001年   319篇
  2000年   287篇
  1999年   259篇
  1998年   128篇
  1997年   156篇
  1996年   171篇
  1995年   175篇
  1994年   139篇
  1993年   161篇
  1992年   234篇
  1991年   209篇
  1990年   207篇
  1989年   242篇
  1988年   244篇
  1987年   205篇
  1986年   204篇
  1985年   216篇
  1984年   189篇
  1983年   229篇
  1982年   170篇
  1981年   159篇
  1980年   156篇
  1979年   229篇
  1978年   181篇
  1977年   164篇
  1976年   149篇
  1975年   128篇
  1974年   119篇
  1973年   125篇
  1971年   106篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
The paper describes the design and use of a studio system which arose out of the need to give demonstrations of experimental procedures to practical classes of up to 150 students. Since the requirements could be specified in some detail it was possible to use novel methods of working which turned out to be very efficient and economical.  相似文献   
142.
A broad view of mathematics education takes it as the study of how people learn and do mathematics. Starting with this view, the actual and potential relationships of mathematics education as are search discipline to mathematics as a field of knowledge and activity and to the mathematicians carrying out that activity are analyzed. This leads to the picture of a gulf between the two scientific communities which are based in different cultures of thinking and research. A (meta-)study of mathematics and all its facets termed here mathematicology is proposed. It could serve as common ground for cooperative studies by mathematicians and mathematics educators. Thereby the gulf will not necessarily become narrower but abridge over the differences and mutual misunderstandings could be built.  相似文献   
143.
The common practice of using discussion groups during case-based learning makes the role of discussion important in these learning environments. However, little empirical research has been done to investigate the influence of discussion on performance and motivation in case-based learning. The purpose of this article is to present the results of a study conducted to examine the role of discussion groups in a case-based environment. College students completed two cases either individually or in small discussion groups. Measures included two case analyses, an attitude survey, time on task, and document analysis. Results revealed significant performance and time differences between instructional methods on the first case, but not on the second case. In addition, results indicated significant differences in student attitudes between treatments. Overall, participants who worked in groups liked their method significantly better than those who worked alone, felt they learned more working in a group than they would have working alone, and expressed a preference for working in a group if they had to do the class over again. Implications for implementing case-based learning and future research are discussed. Anna E. Flynn is Vice President and NAPM Associate Professor with the National Association of Purchasing Management.  相似文献   
144.
145.
This article provides background on national movements toward expanded school mental health (ESMH) programs and school‐based health centers (SBHCs), and presents advantages and challenges of joining these two systems of child and adolescent health care. Delivering ESMH through SBHCs promotes an interdisciplinary approach, health–mental health care integration, and benefits including enhancing referral bases, improving screening of problems, and enhanced confidentiality and privacy. But this integrated approach also presents challenges including managing referrals and significant needs, handling crises, building a focus on prevention and mental health promotion, handling administrative demands, and coping with limited resources. These challenges, ideas for overcoming them, and future directions for this promising service delivery approach are discussed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 297–308, 2003.  相似文献   
146.
In this paper,we prove that the Veronese surface can be determined by the 1-spectrum of the Laplace operator.  相似文献   
147.
In this paper ,a hybrid approach was developed to investigate the transient responses of a multi-span non-uniform flexble spinning shaft with nonlinear and asymmetric supports.The non-uniform spinning shaft with variable parmeters was modeled as a Bernoulli-Euler beam column with sectional constant cross-section properties by the finite element method.The supporting stiffness behavior of the nonlinear supports was described as a piecewise-linear and asymmetric model.The equations of motion in the matrix form of a multi-span non-uniform spinning shaft with nonlinear and asymmetric supports were formulated using Hamilton‘s principle and the assumed mode method.As an example,a spinning rocket with many variable stiffness supports was numerically simulated by the direct integration method.The transient response and dynamic behavior of this rotate-dynamic system are analyzed.  相似文献   
148.
149.
1IntroductionIntrusion detection systems(IDS)can be catego-rizedinto two types bytheir detection algorithms:mis-use detection and anomaly detection.Misuse detectiondefines known attack signatures(using expert know-ledge),and tries to find the ones that ma…  相似文献   
150.
lintroductionMOrpnologicalandnlediantiltersasaclassofnonlineardiscretetilters11avegotWideapplicationsinsignalandimageprocessing.Incontrastwithlinearfilters,medianfiltersandtheirgenerationsareattractivebecausetheyareeasytoimplenlentandcansuppressimpulsenoi…  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