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   2359篇
  免费   62篇
  国内免费   4篇
教育   1752篇
科学研究   116篇
各国文化   60篇
体育   246篇
综合类   1篇
文化理论   28篇
信息传播   222篇
  2023年   5篇
  2022年   11篇
  2021年   20篇
  2020年   43篇
  2019年   62篇
  2018年   96篇
  2017年   104篇
  2016年   91篇
  2015年   59篇
  2014年   88篇
  2013年   530篇
  2012年   78篇
  2011年   74篇
  2010年   59篇
  2009年   69篇
  2008年   86篇
  2007年   63篇
  2006年   69篇
  2005年   61篇
  2004年   47篇
  2003年   63篇
  2002年   64篇
  2001年   43篇
  2000年   31篇
  1999年   35篇
  1998年   23篇
  1997年   36篇
  1996年   35篇
  1995年   35篇
  1994年   19篇
  1993年   21篇
  1992年   18篇
  1991年   25篇
  1990年   19篇
  1989年   24篇
  1988年   11篇
  1987年   11篇
  1986年   14篇
  1985年   10篇
  1984年   13篇
  1983年   15篇
  1982年   22篇
  1981年   17篇
  1980年   6篇
  1979年   19篇
  1978年   9篇
  1977年   12篇
  1976年   11篇
  1974年   7篇
  1945年   3篇
排序方式: 共有2425条查询结果,搜索用时 515 毫秒
131.
132.
One approach to children’s rights in research is to adopt a methodology that focuses on eliciting children’s perspectives. Ensuring representative participation from all children allows a diversity of contexts to be reflected in the results, and points to ways in which improvements can be made in specific settings. In cultural contexts where participation in decision-making is not a traditional role for children, their viewpoints are likely to provide results that highlight differences between cultural norms and children’s rights, and can offer an important focus of dialogue among stakeholders. It is proposed that children’s rights can therefore become integral to the whole process of a quantitative research project. This paper describes such an approach used in a Pacific Islands study, which investigated the quality of schooling through a probability-based sample survey of 1560 children in the first three years of formal education in 55 schools in Vanuatu, the Solomon Islands and Kiribati.  相似文献   
133.
The primary objective for modeling of machining processes is to develop a predictive capability of machining performance in order to facilitate effective planning of machining operations. This capability leads to faster implementation, higher performance, quality at a lower cost. This comes about due to improved selection of machining parameters, optimal fixture design and the avoidance of tool failure. The simulation system presented simultaneously considers the effect of cutter geometry, the cutter's initial position errors, workpiece geometry, machine tool dynamics, and workpiece/fixture system dynamics on the machining process.The integration of all of the above in one model provides an off-line tool to simulate and optimize the machining parameters and the fixture configuration cutting both lead and production time. The modular nature of the simulation system presented allows for the study of many different machining processes. The cutting forces in this system are modeled using a mechanistic approach. NURBS curves and surfaces are utilized for the geometric modeling and simulation of the machining process. While a finite element method is used to model and analyze the workpiece/fixture dynamics. Two case studies are presented to demonstrate the practical application of the presented simulation. The first case presents the optimization of the fixture configuration of a generic automotive component. While the second case presents the results of simulations performed on a novel mill/grind machining process. This process is a combination of face milling and grinding in one operation. Some simulated results are presented along with experimental validation.  相似文献   
134.
It has been shown (Lawrence, S. (2001). Online or invisible? Nature, 411, 521) that journal articles which have been posted without charge on the internet are more heavily cited than those which have not been. Using data from the NASA Astrophysics Data System (ads.harvard.edu) and from the ArXiv e-print archive at Cornell University (arXiv.org) we examine the causes of this effect.  相似文献   
135.
136.
Several scholars contend that learning with computer games and simulations results in students thinking more like professionals. Bearing this goal in mind, we investigated how a group of pharmacy students learnt with an in‐house developed computer simulation, SimPharm. Adopting situated cognition as our theoretical lens, we conducted a case study involving 20 undergraduate students to tease out how they made meaning of a clinical case differently in two different contexts: a typical paper‐based workshop and one enabled by SimPharm. The data collected included audio recordings of classroom discourse, focus group interviews and class observations. The findings identified differences in four areas: framing of the problem; problem‐solving steps and tools used; sources and meaning of feedback; and conceptualisation of the patient. These four areas can serve as axes along which future evaluations of educational simulations can be carried out based on their affordances.  相似文献   
137.
School quality, child wellbeing and parents’ satisfaction   总被引:1,自引:0,他引:1  
Child wellbeing at school and enjoyment of the learning environment are important economic outcomes, in particular because a growing body of research shows they are strongly linked to later educational attainments and labour market success. However, the standard working assumption in the economics of education is that parents choose schools on the basis of test-score performance, and concerns about child happiness are largely ignored. In this paper, we address this omission and investigate to what extent parents’ and children's views of their school are linked to test-score based performance, and to what extent parents’ judgements of school quality are linked to their child's happiness. To do so, we use information on stated attitudes from the Longitudinal Survey of Young People in England (LSYPE) matched to administrative records on pupil achievements in England. Our results suggest that test-score based measures of school quality tend to dominate parental satisfaction with the learning environment. However, school quality along this dimension is not strongly associated with pupil happiness and wellbeing at school.  相似文献   
138.
139.
Regional investment in R&D, technological development and innovation is perceived as being strongly associated with productivity, growth and sustained international competitiveness. One policy instrument by which policy makers have attempted to create regional advantage has been the establishment of publicly funded research centres (PRCs). In this paper we develop a logic model for this type of regional intervention and examine the outputs and longer-term outcomes from a group of (18) publicly funded R&D centres. Our results suggest some positive regional impacts but also identify significant differences in terms of innovation, additionality and sustainability between university-based and company-based PRCs. University-based PRCs have higher levels of short-term additionality, demonstrate higher levels of organisational innovation but prove less sustainable. Company-based PRCs demonstrate more partial additionality in the short-term but ultimately prove more sustainable.  相似文献   
140.
What are the respective roles of indigenous and exogenous factors in the development of high-tech regions? Entrepreneurs and their start-ups have dominated Silicon Valley's economy in recent decades, but a different dynamic was at work from 1940 to 1965, when the Valley emerged as a formidable high-tech region. In key industries (electronics, semiconductors, computers, and aerospace) that defined Silicon Valley as a high-tech cluster during that period, companies based elsewhere played critical roles in planting the organizations that would - through the innovations they made, the technical talent they attracted, and the start-ups they spun off - help make the Valley the world's most admired and emulated high-tech region.  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