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   1474篇
  免费   52篇
  国内免费   14篇
管理学   227篇
民族学   21篇
人口学   48篇
丛书文集   52篇
理论方法论   107篇
综合类   376篇
社会学   582篇
统计学   127篇
  2024年   8篇
  2023年   51篇
  2022年   13篇
  2021年   38篇
  2020年   58篇
  2019年   47篇
  2018年   69篇
  2017年   81篇
  2016年   68篇
  2015年   56篇
  2014年   63篇
  2013年   195篇
  2012年   80篇
  2011年   85篇
  2010年   66篇
  2009年   62篇
  2008年   85篇
  2007年   72篇
  2006年   70篇
  2005年   42篇
  2004年   34篇
  2003年   23篇
  2002年   26篇
  2001年   36篇
  2000年   30篇
  1999年   14篇
  1998年   16篇
  1997年   7篇
  1996年   6篇
  1995年   6篇
  1994年   8篇
  1993年   7篇
  1992年   8篇
  1991年   2篇
  1990年   2篇
  1988年   4篇
  1987年   1篇
  1981年   1篇
排序方式: 共有1540条查询结果,搜索用时 15 毫秒
1.
While the US Supreme Court was considering two related cases involving the constitutionality of same-sex marriage, one major question informing that decision was whether scientific research had achieved consensus regarding how children of same-sex couples fare. Determining the extent of consensus has become a key aspect of how social science evidence and testimony is accepted by the courts. Here, we show how a method of analyzing temporal patterns in citation networks can be used to assess the state of social scientific literature as a means to inform just such a question. Patterns of clustering within these citation networks reveal whether and when consensus arises within a scientific field. We find that the literature on outcomes for children of same-sex parents is marked by scientific consensus that they experience “no differences” compared to children from other parental configurations.  相似文献   
2.
《Journal of Policy Modeling》2020,42(6):1187-1207
This paper investigates the determinants of countries’ choices of monetary policy framework. A brief narrative focused on groupings of countries motivates an econometric analysis which draws on previous work on the determinants of exchange rate regimes, bringing in standard factors as well as the trade networks of potential anchor currency blocs and the financial market depth that are emphasised in the narrative. The model turns out to be able to predict three quarters of countries’ choices, and there is no obvious systematic pattern in the errors. The results have important implications for how countries should choose their monetary policy frameworks.  相似文献   
3.
《Risk analysis》2018,38(8):1559-1575
Security of the systems is normally interdependent in such a way that security risks of one part affect other parts and threats spread through the vulnerable links in the network. So, the risks of the systems can be mitigated through investments in the security of interconnecting links. This article takes an innovative look at the problem of security investment of nodes on their vulnerable links in a given contagious network as a game‐theoretic model that can be applied to a variety of applications including information systems. In the proposed game model, each node computes its corresponding risk based on the value of its assets, vulnerabilities, and threats to determine the optimum level of security investments on its external links respecting its limited budget. Furthermore, direct and indirect nonlinear influences of a node's security investment on the risks of other nodes are considered. The existence and uniqueness of the game's Nash equilibrium in the proposed game are also proved. Further analysis of the model in a practical case revealed that taking advantage of the investment effects of other players, perfectly rational players (i.e., those who use the utility function of the proposed game model) make more cost‐effective decisions than selfish nonrational or semirational players.  相似文献   
4.
5.
主要研究城域网MAC层标准“IEEE 802.6 DQDB”协议的优先故排队性能;提出了一种DQDB协议的优先级实现方案—β分级结构。通过本文给出的文件传输性能分析以及计算机模拟证明,这种新的优先级结构可取得比DQDB现有结构更好的性能,而且易于实现。  相似文献   
6.
借助于李雅谱洛夫理论、矩阵分析方法和It?公式,结合不等式分析技巧,研究了随机细胞神经网络系统的均方指数稳定性,给出了系统的解的二阶矩Liapunov指数估计式和均方指数稳定的充分条件。  相似文献   
7.
提出了一种基于定位辅助按需拓扑维护的超宽带自组网路由算法,该算法利用超宽带技术精确定位信息所获得的网络拓扑信息和路由信息进行分组转发,路由维护阶段在定位信息辅助下采用按需方式进行断链路由的修复和拓扑维护,通过基于位置信息的按需路由发现和限制路由查找范围,以及定位信息和网络拓扑信息的及时更新,在降低协议开销的同时保证了算法的有效性。仿真表明,该算法在分组丢失率、平均端到端时延和路由附加开销等方面具有良好性能,其优良的分布式控制特征能适应超宽带自组网的动态环境。  相似文献   
8.
We discuss the issue of using benchmark doses for quantifying (excess) risk associated with exposure to environmental hazards. The paradigm of low-dose risk estimation in dose-response modeling is used as the primary application scenario. Emphasis is placed on making simultaneous inferences on benchmark doses when data are in the form of proportions, although the concepts translate easily to other forms of outcome data.  相似文献   
9.
提高神经网络模型推广能力的关键是控制模型的复杂度。该文探索了贝叶斯神经网络的非参数回归的建模方法,通过融入模型参数的先验知识,在给定数据样本及模型假设下进行后验概率的贝叶斯推理,使用马尔可夫链蒙特卡罗算法来优化模型控制参数,实现了对神经网络模型中不同部分复杂度的控制,获得了模型参数的后验分布及预测分布。在5个含噪二维函数回归问题上的应用显示了模型的复杂度能根据数据的复杂度而自适应调整,并给出了较好的预测结果。  相似文献   
10.
This paper examines young people's firsthousing acquisition in Spain. The majority ofyoung Spanish people leave home to buy aproperty and to live with a partner and/orchild. We examine the extent to which thistransition dominates first housing moves duringthe 1980s and consider the ways in which widerfamily networks facilitate leaving home to buya property. We then examine characteristicsassociated with deviation from this normativeroute. We find alternative transitions,particularly moving into rented accommodation,are more common among young people from moreadvantaged backgrounds, and those living innorthern Spain.  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