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   3300篇
  免费   101篇
  国内免费   30篇
管理学   270篇
劳动科学   2篇
民族学   22篇
人口学   50篇
丛书文集   306篇
理论方法论   201篇
综合类   1920篇
社会学   249篇
统计学   411篇
  2024年   4篇
  2023年   24篇
  2022年   21篇
  2021年   20篇
  2020年   48篇
  2019年   53篇
  2018年   69篇
  2017年   89篇
  2016年   76篇
  2015年   84篇
  2014年   145篇
  2013年   290篇
  2012年   175篇
  2011年   174篇
  2010年   172篇
  2009年   185篇
  2008年   202篇
  2007年   223篇
  2006年   230篇
  2005年   215篇
  2004年   162篇
  2003年   181篇
  2002年   173篇
  2001年   127篇
  2000年   82篇
  1999年   33篇
  1998年   27篇
  1997年   22篇
  1996年   28篇
  1995年   16篇
  1994年   10篇
  1993年   10篇
  1992年   8篇
  1991年   9篇
  1990年   5篇
  1989年   6篇
  1988年   10篇
  1987年   5篇
  1986年   2篇
  1985年   5篇
  1984年   2篇
  1982年   1篇
  1981年   3篇
  1980年   3篇
  1979年   1篇
  1973年   1篇
排序方式: 共有3431条查询结果,搜索用时 531 毫秒
71.
The present study examined people’s expectations of how incidental emotions could shape others’ reciprocity in trusting situations, whether these expectations affect people’s own behavior, and how accurate these expectations are. Study 1 explored people’s beliefs about the effects of different incidental emotions on another person’s trustworthiness in general. In Studies 2 and 3, senders in trust games faced angry, guilty, grateful, or emotionally neutral responders. Participants who were told about their counterpart’s emotional state acted consistently with their beliefs about how these emotions would affect the other’s trustworthiness. These beliefs were not always correct, however. There were significant deviations between the expected behavior of angry responders and such responders’ actual behavior. These findings raise the possibility that one player’s knowledge of the other’s emotional state may lead to action choices that yield poor outcomes for both players.  相似文献   
72.
Summary. In England, so-called 'league tables' based on examination results and test scores are published annually, ostensibly to inform parental choice of secondary schools. A crucial limitation of these tables is that the most recent published information is based on the current performance of a cohort of pupils who entered secondary schools several years earlier, whereas for choosing a school it is the future performance of the current cohort that is of interest. We show that there is substantial uncertainty in predicting such future performance and that incorporating this uncertainty leads to a situation where only a handful of schools' future performances can be separated from both the overall mean and from one another with an acceptable degree of precision. This suggests that school league tables, including value-added tables, have very little to offer as guides to school choice.  相似文献   
73.
针对大庆外围油田特低渗透油藏剩余油潜力大、井网加密效益差、水驱采收率低等问题,提出了特低渗透油藏 CO2驱技术。通过细管实验和天然岩芯 CO2 驱油实验,确定了 CO2 与高台子油田原油的最小混相压力,评价了特低渗透砂岩油藏 CO2 驱油效果。实验结果表明,CO2 驱可以应用于高台子油田,并取得较好的驱油效果。当天然岩芯空气渗透率为0.58 mD 时,在水驱基础上,气驱可以进一步提高采收率 8% 以上,特低渗透油藏实施 CO2 驱油技术是可行的。  相似文献   
74.
Abstract

We introduce a new family of distributions using truncated discrete Linnik distribution. This family is a rich family of distributions which includes many important families of distributions such as Marshall–Olkin family of distributions, family of distributions generated through truncated negative binomial distribution, family of distributions generated through truncated discrete Mittag–Leffler distribution etc. Some properties of the new family of distributions are derived. A particular case of the family, a five parameter generalization of Weibull distribution, namely discrete Linnik Weibull distribution is given special attention. This distribution is a generalization of many distributions, such as extended exponentiated Weibull, exponentiated Weibull, Weibull truncated negative binomial, generalized exponential truncated negative binomial, Marshall-Olkin extended Weibull, Marshall–Olkin generalized exponential, exponential truncated negative binomial, Marshall–Olkin exponential and generalized exponential. The shape properties, moments, median, distribution of order statistics, stochastic ordering and stress–strength properties of the new generalized Weibull distribution are derived. The unknown parameters of the distribution are estimated using maximum likelihood method. The discrete Linnik Weibull distribution is fitted to a survival time data set and it is shown that the distribution is more appropriate than other competitive models.  相似文献   
75.
凯恩斯的宏观经济理论既不涉及现实的政治维度,也不关注微观经济层面的资源配置效率问题,这样的理论应用于现实的结果很可能是弊大于利。作为应用凯恩斯理论的总需求管理思想的产物,中国4万亿的经济刺激计划在政治层面难以避免寻租和腐败、政治权力固化等问题,在经济层面有可能导致资源配置的扭曲。虽然政府出台了各种监管措施以预防这种可能出现的弊病,但经验和理论都告诉我们这些措施的有效性是有限的。  相似文献   
76.
达尔文进化论不仅确立了重要的生态原则,而且这些原则具有十分丰富的科学意义。深入阐发达尔文进化论生态意义,有助于我们深化对人与自然的关系、人类在自然进化中的位置、人类文明发展与生态建设的关系等问题的认识。  相似文献   
77.
We consider assortment problems under a mixture of multinomial logit models. There is a fixed revenue associated with each product. There are multiple customer types. Customers of different types choose according to different multinomial logit models whose parameters depend on the type of the customer. The goal is to find a set of products to offer so as to maximize the expected revenue obtained over all customer types. This assortment problem under the multinomial logit model with multiple customer types is NP‐complete. Although there are heuristics to find good assortments, it is difficult to verify the optimality gap of the heuristics. In this study, motivated by the difficulty of finding optimal solutions and verifying the optimality gap of heuristics, we develop an approach to construct an upper bound on the optimal expected revenue. Our approach can quickly provide upper bounds and these upper bounds can be quite tight. In our computational experiments, over a large set of randomly generated problem instances, the upper bounds provided by our approach deviate from the optimal expected revenues by 0.15% on average and by less than one percent in the worst case. By using our upper bounds, we are able to verify the optimality gaps of a greedy heuristic accurately, even when optimal solutions are not available.  相似文献   
78.
由于最严格水资源管理存在着水资源供给、用水总量、用水关系和用水管理等诸多不确定,采用可操作的实施就成为落实最严格水资源管理的关键。研究发现:(1)通过最严格水资源管理的压力—状态—响应(PSR)分析可知,最严格水资源管理的实施路径与水资源适应性管理在目标理念、工作途径、核心问题和保障需求方面有着一致性;(2)水资源适应性政策选择能够促进最严格水资源管理的有效落实,为此给出了适应性政策选择程序,为最严格水资源管理落实的政策选择提供参考依据。  相似文献   
79.
居民出行方式选择影响因素的研究述评   总被引:1,自引:0,他引:1  
居民出行方式选择事关家庭能源消费,对于节能减排目标实现具有重要影响。基于个体、群体两个对象,从主观、客观两个视角梳理了居民出行方式选择行为的主要影响因素,并深入阐明了各影响因素的概念、相互联系及作用机制。研究发现,目前该领域的研究趋势正在由主观因素转变到客观因素,从个体因素转变到群体因素,且存在以下不足之处:若干心理变量的解释和作用机制仍存在争议;缺乏行为的社会网络构建和扩散分析;过度依赖经典的“刺激-反应”行为主义模式和“成本-收益”的理性决策架构;缺乏由行为到态度等心理变量的逆向反馈分析。未来应结合中国国情,通过系统学和社会网络的方法探究居民出行方式选择的动机、实施、强化、约束、反馈、路径及扩散等动态过程,并引入实验法来加强引导政策的研究。  相似文献   
80.
以大跨黄土隧道下穿公路安全施工为背景,对隧道下穿公路的安全施工方案进行研究。基于公路路面破损指数与下穿公路施工风险事件引起路面最大沉降之间的关系确定了隧道下穿施工可能引起的路面最大允许沉降量,并据此制定出施工管理基准,对比分析了CRD和CD法引起的隧道拱顶沉降、地表最大沉降、支护受力和隧道周边地层塑性区特征,建议采用CD法进行下穿施工。下穿孙辛路施工监测结果表明,采用CD法保证了隧道施工安全和孙辛路的正常通行。  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