首页 | 官方网站   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   90623篇
  免费   1964篇
  国内免费   3篇
社会科学   92590篇
  2023年   514篇
  2021年   574篇
  2020年   1521篇
  2019年   2215篇
  2018年   2063篇
  2017年   3139篇
  2016年   2359篇
  2015年   2047篇
  2014年   2624篇
  2013年   18861篇
  2012年   2307篇
  2011年   2119篇
  2010年   1935篇
  2009年   2180篇
  2008年   2003篇
  2007年   1801篇
  2006年   2054篇
  2005年   2258篇
  2004年   2122篇
  2003年   1859篇
  2002年   1961篇
  2001年   1995篇
  2000年   1777篇
  1999年   1691篇
  1998年   1488篇
  1997年   1337篇
  1996年   1311篇
  1995年   1325篇
  1994年   1298篇
  1993年   1280篇
  1992年   1279篇
  1991年   1193篇
  1990年   1178篇
  1989年   1026篇
  1988年   1107篇
  1987年   1002篇
  1986年   884篇
  1985年   1056篇
  1984年   1125篇
  1983年   996篇
  1982年   924篇
  1981年   854篇
  1980年   805篇
  1979年   878篇
  1978年   772篇
  1977年   691篇
  1976年   647篇
  1975年   634篇
  1974年   513篇
  1973年   437篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
The product of two independent or dependent scalar normal variables, sums of products, sample covariances, and general bilinear forms are considered. Their distributions are shown to belong to a class called generalized Laplacian. A growth-decay mechanism is also shown to produce such a generalized Laplacian. Sets of necessary and sufficient conditions are derived for bilinear forms to belong to this class. As a generalization, the distributions of rectangular matrices associated with multivariate normal random vectors are also discussed.  相似文献   
22.
23.
24.
25.
26.
27.
The authors examined the impact of sense of coherence on the career thought processes of a sample of college students. A. Antonovsky (1987) defined sense of coherence as the global orientation that the world is comprehensible, manageable, and meaningful. Study participants completed the Sense of Coherence Scale (A. Antonovsky, 1987) and the Career Thoughts Inventory (CTI; J. P. Sampson, G. W. Peterson, J. G. Lenz, R. C. Reardon, & D. E. Saunders, 1996). Multivariate tests indicated a medium relationship between sense of coherence and CTI Total and subscale scores; sense of coherence accounted for 14% of the variance. Univariate tests also indicated a medium relationship between sense of coherence and each subscale.  相似文献   
28.
29.
30.
Abstract In recent years, church burnings in the South have attracted a great deal of attention. Many commentators have charged that they are a product of strained race relations throughout the South, and particularly of severe racial tensions in Southern rural areas. In this study we evaluate these claims. We begin by mapping the spatial coordinates of recorded church burnings from 1990 to 1997, and find that church arsons indeed are concentrated in the South. Church burnings, however, are a more urban phenomenon than popular media accounts would suggest. Our analysis then explores the influence of contextual factors (population and locale, racial composition and inequality, so‐cioeconomic conditions, local religious ecology, and patterns of reported crime) on church burnings in counties located in the study region. Logistic regression models confirm that church arsons are most likely to occur in small metropolitan statistical areas (MSAs) and non‐MSA counties containing a city of at least 10,000 residents. Church burnings also are especially likely in counties with a higher percentage of black residents, a larger number of churches relative to the rest of the state, and a higher arson rate. We conclude by discussing the implications of these findings for future research and public policy.  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-23

京公网安备 11010802026262号