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   3000篇
  免费   114篇
  国内免费   1篇
管理学   419篇
民族学   9篇
人口学   262篇
丛书文集   18篇
理论方法论   345篇
综合类   36篇
社会学   1240篇
统计学   786篇
  2023年   20篇
  2021年   19篇
  2020年   55篇
  2019年   79篇
  2018年   108篇
  2017年   120篇
  2016年   70篇
  2015年   80篇
  2014年   96篇
  2013年   607篇
  2012年   122篇
  2011年   103篇
  2010年   79篇
  2009年   64篇
  2008年   82篇
  2007年   79篇
  2006年   63篇
  2005年   59篇
  2004年   47篇
  2003年   30篇
  2002年   51篇
  2001年   61篇
  2000年   56篇
  1999年   47篇
  1998年   40篇
  1997年   41篇
  1996年   32篇
  1995年   33篇
  1994年   41篇
  1993年   36篇
  1992年   47篇
  1991年   48篇
  1990年   35篇
  1989年   34篇
  1988年   43篇
  1987年   19篇
  1986年   26篇
  1985年   38篇
  1984年   31篇
  1983年   41篇
  1982年   27篇
  1981年   23篇
  1980年   22篇
  1979年   23篇
  1978年   40篇
  1977年   20篇
  1976年   26篇
  1975年   25篇
  1974年   15篇
  1972年   14篇
排序方式: 共有3115条查询结果,搜索用时 265 毫秒
921.
Closed‐loop supply chains (CLSC) have product returns at the center of attention. Our view is that CLSC are best managed from a business perspective where organizations seek to maximize value recovery. The research in the feature issue, and our experiences, shows that there are still numerous, unresolved, managerially relevant issues that deserve further investigation. We also observe that there is a pressing need to validate the assumptions in our models using interdisciplinary, industry‐driven research. The time is right for production and operations management to play a central role in the sustainability movement slowly taking hold in practice.  相似文献   
922.
A warping is a function that deforms images by mapping between image domains. The choice of function is formulated statistically as maximum penalized likelihood, where the likelihood measures the similarity between images after warping and the penalty is a measure of distortion of a warping. The paper addresses two issues simultaneously, of how to choose the warping function and how to assess the alignment. A new, Fourier–von Mises image model is identified, with phase differences between Fourier-transformed images having von Mises distributions. Also, new, null set distortion criteria are proposed, with each criterion uniquely minimized by a particular set of polynomial functions. A conjugate gradient algorithm is used to estimate the warping function, which is numerically approximated by a piecewise bilinear function. The method is motivated by, and used to solve, three applied problems: to register a remotely sensed image with a map, to align microscope images obtained by using different optics and to discriminate between species of fish from photographic images.  相似文献   
923.
Objective. We make use of individual‐level survey data from the 2006 midterm election in order to determine the degree to which redistricting affected the vote choice of whites residing in Georgia Congressional Districts 8 and 12. Methods. A multivariate probit model was used to assess the probability of voting for the GOP House candidate among voters represented by the same incumbent before and after redistricting versus voters who had been newly drawn into one of these districts. Results. Despite a national tide that favored the Democratic Party in the 2006 elections, redrawn whites were more likely to vote for the Republican challengers in the districts surveyed. Conclusions. Our findings indicate that redistricting can be used to dampen the incumbency advantage. In addition, the findings of this research also speak to the continuing Republican realignment of white voters in the Deep South and to the recognition that the effects of redistricting are dependent on political context.  相似文献   
924.
While a growing body of literature has investigated the health impact of intimate partner violence (IPV), less has been written on the social determinants of IPV. The authors use multilevel modeling methods to analyze data from a sample of 83,627 women in India to examine the socioeconomic and demographic patterning of the state‐ and neighborhood‐level variation in, and the state‐ and/or neighborhood‐level characteristics related to, IPV. This study finds social gradients in IPV in which women who are uneducated, from marginalized castes, and living in poor households have higher likelihood of reporting IPV than those living in advantaged circumstances. The results also show differences in IPV between neighborhoods and between states that are partially explained by state levels of gender inequality. The results suggest that changing cultural norms to promote the status of women and increasing the educational and economic opportunities for all people could decrease the prevalence of IPV.  相似文献   
925.
Trimmed U  -statistics can be constructed in two different ways: by basing the statistic on a trimmed sample or by averaging the trimmed set of kernel values. Mild conditions are given to ensure the rate of convergence to normality is O(n-1/2)O(n-1/2) in both cases.  相似文献   
926.
Motivated by problems of modelling torsional angles in molecules, Singh, Hnizdo & Demchuk (2002) proposed a bivariate circular model which is a natural torus analogue of the bivariate normal distribution and a natural extension of the univariate von Mises distribution to the bivariate case. The authors present here a multivariate extension of the bivariate model of Singh, Hnizdo & Demchuk (2002). They study the conditional distributions and investigate the shapes of marginal distributions for a special case. The methods of moments and pseudo‐likelihood are considered for the estimation of parameters of the new distribution. The authors investigate the efficiency of the pseudo‐likelihood approach in three dimensions. They illustrate their methods with protein data of conformational angles  相似文献   
927.
928.
In 2011, the global human population reached 7 billion and medium variant projections indicate that it will exceed 9 billion before 2045. Theoretical and empirical perspectives suggest that this growth could lead to an increase in the likelihood of adverse events (e.g., food shortages, climate change, etc.) and/or the severity of adverse events (e.g., famines, natural disasters, etc.). Several scholars have posited that the size to which the global population grows and the extent to which this growth increases the likelihood of adverse outcomes will largely be shaped by individuals’ decisions (in households, organizations, governments, etc.). In light of the strong relationship between perceived risk and decision behaviors, it is surprising that there remains a dearth of empirical research that specifically examines the perceived risks of population growth and how these perceptions might influence related decisions. In an attempt to motivate this important strand of research, this article examines the major risks that may be exacerbated by global population growth and draws upon empirical work concerning the perception and communication of risk to identify potential directions for future research. The article also considers how individuals might perceive both the risks and benefits of population growth and be helped to better understand and address the related issues. The answers to these questions could help humanity better manage the emerging consequences of its continuing success in increasing infant survival and adult longevity.  相似文献   
929.
Prejudice and popularity represent two major areas of research. Yet studies have not considered whether prejudiced adolescents actually can be popular. Among 572 high school students (Mage = 15.80 years), the current study tested the association between popularity (based on sociometric peer nominations) and sexual prejudice against gay and lesbian individuals, moderated by gender and perspective taking. As hypothesized, the association was significant for males but not females, and it was significant for adolescents lower on perspective taking but not those higher on perspective taking. Moreover, adolescents who were popular and expressed strong sexual prejudice were more likely to engage in homophobic behavior than prejudiced adolescents who were less popular. Popular adolescents with strong sexual prejudice beliefs may be more prone to use homophobic behavior as a way to maintain their dominant position. Similarly, prejudiced adolescents who are popular may face less pushback for their engagement in homophobic behavior. Continued attention to the connection between sexual prejudice and popularity is important because of the high status, influence, and visibility of popular adolescents.  相似文献   
930.
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