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   1622篇
  免费   109篇
  国内免费   14篇
管理学   237篇
民族学   6篇
人口学   24篇
丛书文集   69篇
理论方法论   62篇
综合类   604篇
社会学   203篇
统计学   540篇
  2024年   2篇
  2023年   22篇
  2022年   21篇
  2021年   30篇
  2020年   50篇
  2019年   73篇
  2018年   68篇
  2017年   93篇
  2016年   61篇
  2015年   76篇
  2014年   107篇
  2013年   284篇
  2012年   109篇
  2011年   95篇
  2010年   76篇
  2009年   84篇
  2008年   66篇
  2007年   61篇
  2006年   54篇
  2005年   59篇
  2004年   39篇
  2003年   47篇
  2002年   39篇
  2001年   26篇
  2000年   19篇
  1999年   15篇
  1998年   11篇
  1997年   6篇
  1996年   9篇
  1995年   7篇
  1994年   8篇
  1993年   7篇
  1992年   4篇
  1991年   2篇
  1990年   3篇
  1988年   4篇
  1986年   1篇
  1984年   1篇
  1981年   2篇
  1979年   2篇
  1977年   2篇
排序方式: 共有1745条查询结果,搜索用时 15 毫秒
1.
This article explores how a lack of access to increasingly complex and overlapping digital communications platforms in times of disaster for people with disabilities has the potential to make already life-threatening situations considerably more dangerous. As we are increasingly coming to rely on a social media mash-up of digital platforms to assist in communications during disaster situations, the issue of accessibility for people with disabilities is as dire as if it was high ground during a tsunami or transport during a typhoon. The contemporary social media environment is characterised by a complex and overlapping network of complementary platforms, populated by user-generated content, where people communicate and exchange ideas. In this environment, YouTube videos are posted to Facebook and embedded in blogs, and Twitter is used to link to these other sites and is itself embedded in other platforms. These networks are increasingly supplementing and supplanting more traditional communication platforms, such as the television and radio, particularly in times of disaster. The concern of this paper is that the elements from which this mash-up of communications channels is made are not always accessible to people with disabilities. This evolving network of social media-based communication exposes the limits of existing Internet-based universal design.  相似文献   
2.
研究了用电加热法解决用于动态气流温度测量的小惯性热电偶时间常数的实验测定问题。提出采取在稳定气流场中用电加热热电偶然后迅速切断电源的方法 ,获取较为理想的负温度阶跃 ,进而由热电偶的阶跃响应曲线求得时间常数。设计了相应的设备 ,并进行了实验测定 ,获得了较好的结果。  相似文献   
3.
植物液泡膜H+-ATPase及其在胁迫中的响应   总被引:4,自引:0,他引:4  
V-ATPase存在于所有已知的真核生物中,在植物的生长、发育、信号转导和胁迫适应过程中发挥着重要的作用.近年来对V-ATPase的结构、功能和调节机制的研究进展较快,V-ATPase主要亚基已经完成序列测定及分析,并对各亚基生理功能、V-ATPase全酶复合体的组装、调控也有了较为深入的研究.该文在阐述植物细胞液泡膜H -ATPase的基本结构的基础上,介绍V-ATPase亚基组成、编码基因及在胁迫应答中的响应.  相似文献   
4.
The problem considered is that of finding an optimum measurement schedule to estimate population parameters in a nonlinear model when the patient effects are random. The paper presents examples of the use of sensitivity functions, derived from the General Equivalence Theorem for D-optimality, in the construction of optimum population designs for such schedules. With independent observations, the theorem applies to the potential inclusion of a single observation. However, in population designs the observations are correlated and the theorem applies to the inclusion of an additional measurement schedule. In one example, three groups of patients of differing size are subject to distinct schedules. Numerical, as opposed to analytical, calculation of the sensitivity function is advocated. The required covariances of the observations are found by simulation.  相似文献   
5.
读者接受理论为文学翻译提供了一个更为开放的视角,值得重视和借鉴。然而,如果全盘接受读者接受理论的观点,把文学翻译仅仅看作一种译者主体行为,势必会导致不准确的翻译。读者对于文化空缺词的接受能力是一个历史的动态变化过程。  相似文献   
6.
Low dose risk estimation via simultaneous statistical inferences   总被引:2,自引:0,他引:2  
Summary.  The paper develops and studies simultaneous confidence bounds that are useful for making low dose inferences in quantitative risk analysis. Application is intended for risk assessment studies where human, animal or ecological data are used to set safe low dose levels of a toxic agent, but where study information is limited to high dose levels of the agent. Methods are derived for estimating simultaneous, one-sided, upper confidence limits on risk for end points measured on a continuous scale. From the simultaneous confidence bounds, lower confidence limits on the dose that is associated with a particular risk (often referred to as a bench-mark dose ) are calculated. An important feature of the simultaneous construction is that any inferences that are based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the bench-mark dose.  相似文献   
7.
无因管理问题的研究   总被引:3,自引:0,他引:3  
无因管理作为民法法律之债的发生依据之一,应当根据社会的发展赋予其新的价值。本文试从无因管理的社会意义和法律性质、成立条件、效力、类型化及类型化无因管理的法律效果等方面就无因管理的有关问题进行了研究。  相似文献   
8.
Longitudinal data often contain missing observations, and it is in general difficult to justify particular missing data mechanisms, whether random or not, that may be hard to distinguish. The authors describe a likelihood‐based approach to estimating both the mean response and association parameters for longitudinal binary data with drop‐outs. They specify marginal and dependence structures as regression models which link the responses to the covariates. They illustrate their approach using a data set from the Waterloo Smoking Prevention Project They also report the results of simulation studies carried out to assess the performance of their technique under various circumstances.  相似文献   
9.
Summary.  Official employment-related performance indicators in UK higher education are based on the population of students responding to the 'First destination supplement' (FDS). This generates potentially biased performance indicators as this population of students is not necessarily representative of the full population of leavers from each institution. University leavers who do not obtain qualifications and those who do not respond to the FDS are not included within the official analysis. We compare an employment-related performance indicator based on those students who responded to the FDS with alternative approaches which address the potential non-random nature of this subgroup of university leavers.  相似文献   
10.
教师效能感研究述评   总被引:1,自引:0,他引:1  
教师效能感的主要理论模型建构主要有罗特的控制点理论和班杜拉的自我效能理论。教师效能感通过教师行为而对学生自我效能及学习能力与成绩起作用,与此同时,环境因素和教师自身因素也对教师的教学效能感产生影响。  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