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   3384篇
  免费   134篇
管理学   575篇
民族学   28篇
人才学   4篇
人口学   233篇
丛书文集   19篇
理论方法论   385篇
综合类   23篇
社会学   1754篇
统计学   497篇
  2023年   26篇
  2022年   12篇
  2021年   15篇
  2020年   67篇
  2019年   105篇
  2018年   88篇
  2017年   124篇
  2016年   109篇
  2015年   90篇
  2014年   93篇
  2013年   572篇
  2012年   118篇
  2011年   107篇
  2010年   100篇
  2009年   97篇
  2008年   116篇
  2007年   103篇
  2006年   114篇
  2005年   138篇
  2004年   97篇
  2003年   103篇
  2002年   92篇
  2001年   73篇
  2000年   53篇
  1999年   64篇
  1998年   54篇
  1997年   38篇
  1996年   38篇
  1995年   32篇
  1994年   55篇
  1993年   49篇
  1992年   40篇
  1991年   46篇
  1990年   41篇
  1989年   36篇
  1988年   35篇
  1987年   36篇
  1986年   26篇
  1985年   43篇
  1984年   38篇
  1983年   28篇
  1982年   30篇
  1981年   19篇
  1980年   16篇
  1979年   13篇
  1978年   20篇
  1977年   16篇
  1976年   15篇
  1975年   12篇
  1974年   17篇
排序方式: 共有3518条查询结果,搜索用时 531 毫秒
11.
12.
Quantifying uncertainty in the biospheric carbon flux for England and Wales   总被引:1,自引:0,他引:1  
Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO2) concentrations in the atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 1012 g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.  相似文献   
13.
1938年夏天,美国年轻学者科尼利尔斯·奥斯古德为了履行与燕京大学的合作计划,不远万里来到滇池西岸一个名不见经传的小村庄调查.1961年,他开启尘封的笔记本,整理旧资料,补充新文献,完成了<旧中国的农村生活:对云南高峣的社区研究>.70年过去,重温科尼利尔斯·奥斯古德的研究历程,我们仍会从中获得许多有益的启示.  相似文献   
14.
In this work, some corporate websites of the chemical industry of Tarragona (Spain) are studied, analysing how the chemical trade associations and companies present information and/or encourage dialogue with the community on issues relating to the chemical risk and their environmental, health and safety (EHS) performance. The results suggest that the chemical industry in Tarragona uses the corporate websites mainly to disseminate information about its EHS commitments and performance, but they do not encourage dialogue with the community through the Internet.  相似文献   
15.
Over the last ten years in Australia the social component of Australian Environmental Impact statements has gradually increased in size as the importance of Social Impact Analysis has been recognised. This commendable trend has not been without mishap, however, and there remain many areas largely ignored in Social Impact Assessment. This paper seeks to identify these areas, identifying value questions that need to be addressed in the preparation of the social impact component.  相似文献   
16.
Using an overlapping-generations model in which households may have either finite or infinite horizons, I derive the implications of each horizon for the steady-state real interest rate. I then formulate an econometric model of the steady-state real interest rate and devise tests that can distinguish between finite and infinite horizons. These tests are applied to annual and quarterly U.S. data, which span the period 1875–1988. The results are inconsistent with finite horizons, and broadly consistent with infinite horizons.  相似文献   
17.
Twelve problem poker machine players and thirteen horse race gamblers (20 males and 5 females; age range 28–69) completed a series of questionnaires which assessed levels of anxiety, their preferred state of arousal and their motivations to gamble. As predicted, problem poker machine gamblers were found to be more anxious and reported avoiding arousal more frequently than the horse race gamblers. Alternately, problem horse race gamblers were found to prefer heightened levels of arousal and appeared to gamble to achieve these optimal levels of arousal. However, there was no difference between the groups on proneness to boredom. The present results provide evidence which is consistent with the Reversal theory and its application to the field of problem gambling.  相似文献   
18.
19.
20.
This article provides an overview of social trust, examining its various aspects and components. Trust is best understood in a sociological sense by focusing on its important relational characteristic. Following this lead, the article discusses briefly how social trust relates to social capital and examines factors that shape the development of social trust, along with outcomes related to variations in trust, classifying them by analytical level (i.e., individual, community, group, organizational, and societal). The article concludes by assessing the strengths and weaknesses of existing research and by identifying some important questions that have not yet been adequately addressed.  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