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   1302篇
  免费   41篇
管理学   185篇
民族学   8篇
人口学   89篇
丛书文集   7篇
理论方法论   196篇
综合类   6篇
社会学   752篇
统计学   100篇
  2023年   6篇
  2022年   8篇
  2021年   8篇
  2020年   26篇
  2019年   30篇
  2018年   54篇
  2017年   57篇
  2016年   47篇
  2015年   30篇
  2014年   42篇
  2013年   219篇
  2012年   41篇
  2011年   45篇
  2010年   53篇
  2009年   40篇
  2008年   46篇
  2007年   62篇
  2006年   43篇
  2005年   47篇
  2004年   36篇
  2003年   38篇
  2002年   41篇
  2001年   23篇
  2000年   21篇
  1999年   24篇
  1998年   18篇
  1997年   13篇
  1996年   16篇
  1995年   13篇
  1994年   17篇
  1993年   9篇
  1992年   10篇
  1991年   10篇
  1990年   10篇
  1989年   6篇
  1988年   10篇
  1987年   12篇
  1986年   10篇
  1985年   15篇
  1984年   7篇
  1983年   13篇
  1982年   10篇
  1981年   12篇
  1980年   8篇
  1979年   9篇
  1978年   5篇
  1977年   3篇
  1975年   4篇
  1974年   6篇
  1973年   3篇
排序方式: 共有1343条查询结果,搜索用时 0 毫秒
61.

The development of control systems and supporting software remains one of the greatest obstacles to the widespread implementation of highly adaptive reconfigurable automation technology. This paper will present the structure of a modular automation control system designed to support rapid reconfiguration and redeployment of automation components. The paper will first present the concept of a layered system architecture and the use of modular automation components to support the construction of a wide variety of automated systems. This layered system architecture is then applied to the proposed modular supervisory control system responsible for configuring and driving automated production resources. Each of the control components comprising this modular control system will be presented.  相似文献   
62.
This article documents key aspects of the role played by University students in Botswana in the liberation struggle, from the early years of the University in the mid‐1960s to the year of Zimbabwe’s independence in 1980. Three demonstrations by University students are analysed, and the article concludes that, contrary to the received literature, the University contributed to the liberation struggle in a meaningful way. Although students at the University continued to play a part in the liberation struggle after 1980, this period is not discussed as the liberation struggle became just one of the key agenda items in a broadened political programme that focussed on local concerns of the students such as fees, allowances, institutional governance and democratisation.  相似文献   
63.
64.
65.
As real‐time language data becomes increasingly available for sociolinguistic research, a growing number of studies are benefitting from it in order to study language changes in progress, some of which even explicitly seek to scrutinize the Apparent‐Time Construct itself. Vanishingly few real‐time studies, however, have focused specifically on stable sociolinguistic variables, leaving an important gap in our understanding of the Apparent‐Time Construct's abilities to model real‐time facts. In an effort to address this gap, the present study analyzes a presumably stable sociolinguistic variable – final /z/ devoicing – in extreme northwestern Indiana through real and apparent time. A series of Varbrul analyses indicate that this variable is, indeed, stable throughout the 20 years of real time covered by the data and that its stability is successfully modeled in apparent time. Additionally, similarities in /z/ devoicing between this community and some other communities where it has also been studied are identified and discussed.  相似文献   
66.
67.
In this article, we present a compressive sensing based framework for generalized linear model regression that employs a two-component noise model and convex optimization techniques to simultaneously detect outliers and determine optimally sparse representations of noisy data from arbitrary sets of basis functions. We then extend our model to include model order reduction capabilities that can uncover inherent sparsity in regression coefficients and achieve simple, superior fits. Second, we use the mixed ?2/?1 norm to develop another model that can efficiently uncover block-sparsity in regression coefficients. By performing model order reduction over all independent variables and basis functions, our algorithms successfully deemphasize the effect of independent variables that become uncorrelated with dependent variables. This desirable property has various applications in real-time anomaly detection, such as faulty sensor detection and sensor jamming in wireless sensor networks. After developing our framework and inheriting a stable recovery theorem from compressive sensing theory, we present two simulation studies on sparse or block-sparse problems that demonstrate the superior performance of our algorithms with respect to (1) classic outlier-invariant regression techniques like least absolute value and iteratively reweighted least-squares and (2) classic sparse-regularized regression techniques like LASSO.  相似文献   
68.
This study assesses the combined impact of multiple certifications (i.e. ISO 9001, ISO 14001, OHSAS 18001) on perceived performance dimensions related to quality, environmental and occupational health and safety. Using survey data collected from 59 Irish manufacturing plants in 2014, we employed MANCOVA and regression analysis to test our proposed hypothesis. The results suggest that companies that are simultaneously ISO 9001, ISO 14001 and OHSAS 18001 certified are significantly better performers with regard to environmental and occupational health and safety compared to companies without multiple certifications. However, from a perceived quality performance perspective, having these multiple certifications doesn’t seem to be an effective performance improvement tool.  相似文献   
69.
Advances in information technology, particularly in the e‐business arena, are enabling firms to rethink their supply chain strategies and explore new avenues for inter‐organizational cooperation. However, an incomplete understanding of the value of information sharing and physical flow coordination hinder these efforts. This research attempts to help fill these gaps by surveying prior research in the area, categorized in terms of information sharing and flow coordination. We conclude by highlighting gaps in the current body of knowledge and identifying promising areas for future research.  相似文献   
70.
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