全文获取类型
收费全文 | 2359篇 |
免费 | 62篇 |
国内免费 | 4篇 |
专业分类
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 |
出版年
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.
Michael J. Kurtz Guenther Eichhorn Alberto Accomazzi Carolyn Grant Markus Demleitner Edwin Henneken Stephen S. Murray 《Information processing & management》2005,41(6):1395-1402
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.
Swee‐Kin Loke June Tordoff Michael Winikoff Jenny McDonald Peter Vlugter Stephen Duffull 《British journal of educational technology : journal of the Council for Educational Technology》2011,42(5):865-874
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.
Stephen B. Adams 《Research Policy》2011,40(3):368-379
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