全文获取类型
| 收费全文 | 2540篇 |
| 免费 | 39篇 |
| 国内免费 | 138篇 |
专业分类
| 教育 | 1428篇 |
| 科学研究 | 742篇 |
| 各国文化 | 5篇 |
| 体育 | 126篇 |
| 综合类 | 121篇 |
| 文化理论 | 6篇 |
| 信息传播 | 289篇 |
出版年
| 2023年 | 8篇 |
| 2022年 | 34篇 |
| 2021年 | 42篇 |
| 2020年 | 85篇 |
| 2019年 | 45篇 |
| 2018年 | 63篇 |
| 2017年 | 45篇 |
| 2016年 | 45篇 |
| 2015年 | 105篇 |
| 2014年 | 169篇 |
| 2013年 | 209篇 |
| 2012年 | 219篇 |
| 2011年 | 232篇 |
| 2010年 | 202篇 |
| 2009年 | 205篇 |
| 2008年 | 190篇 |
| 2007年 | 183篇 |
| 2006年 | 137篇 |
| 2005年 | 113篇 |
| 2004年 | 104篇 |
| 2003年 | 66篇 |
| 2002年 | 63篇 |
| 2001年 | 36篇 |
| 2000年 | 32篇 |
| 1999年 | 25篇 |
| 1998年 | 12篇 |
| 1997年 | 6篇 |
| 1996年 | 13篇 |
| 1995年 | 2篇 |
| 1994年 | 5篇 |
| 1993年 | 5篇 |
| 1992年 | 1篇 |
| 1991年 | 1篇 |
| 1990年 | 1篇 |
| 1989年 | 6篇 |
| 1988年 | 1篇 |
| 1987年 | 4篇 |
| 1986年 | 1篇 |
| 1982年 | 1篇 |
| 1976年 | 1篇 |
排序方式： 共有2717条查询结果，搜索用时 15 毫秒
961.
Yoshiaki Takei Erik P. Blucker Hiroshi Nohara Noriyoshi Yamashita 《Journal of sports sciences》2013,31(11):849-863
The aim of this study was to determine the mechanical variables that govern success of the Hecht vault. The participants were 122 male gymnasts from 30 countries performing the vault at the 1995 World Gymnastics Championships. The vaults were filmed using a Photosonics 16-mm motion picture camera operating at 100 Hz. Approximately 80 frames were digitized for each vault analysed. The method of Hay and Reid was used to develop a theoretical model to identify the mechanical and physical variables that determine linear and angular motions of the vault. Correlational analysis was used to establish the strength of the relationship between the causal mechanical variables identified in the model and the judges' scores. Significant correlations (P ? 0.005) indicated that the following were important determinants of success: large horizontal and vertical velocities at take-off from the board and the horse; large vertical and angular distances of pre-flight; large vertical impulses of high force and short duration exerted on the horse and the resulting large changes in vertical velocity on the horse; and large horizontal and vertical distances and long times of post-flight. Of the 18 significant variables identified in the present study, the angular distance of pre- and post-flights, the horizontal velocity and angular momentum at take-off from the horse, and the average moment of inertia and duration of post-flight collectively accounted for 57% of the variation in the judges' scores. 相似文献
962.
This study involved a theoretical and an experimental investigation of the direct free kick in soccer. Our aim was to develop a mathematical model of the ball's flight incorporating aerodynamic lift and drag forces to explore this important 'set-play'. Trajectories derived from the model have been compared with those obtained from detailed video analysis of experimental kicks. Representative values for the drag and lift coefficients have been obtained, together with the implied orientation of the ball's spin axis in flight. The drag coefficient varied from 0.25 to 0.30 and the lift coefficient from 0.23 to 0.29. These values, used with a simple model of a defensive wall, have enabled free kicks to be simulated under realistic conditions, typical of match-play. The results reveal how carefully attackers must engineer the dynamics of a successful kick. For a central free kick some 18.3 m (20 yards) from goal with a conventional wall, and initial speed of 25 m·s?1, the ball's initial elevation must be constrained between 16.5° and 17.5° and the ball kicked with almost perfect sidespin. 相似文献
963.
964.
《Clearing house (Menasha, Wis.)》2012,85(6):235-245
AbstractOpportunities to learn how to develop engaging learning experiences are vital for preservice teachers. This article describes an in-class modeling activity, provides assignment guidelines, and includes examples of candidates' completed tasks when developing technology-integrated instruction using Quick Response (QR) codes. The content of participants' (n?=?75) tasks were analyzed for complexity following the SAMR model (Pnuentedura 2013). Most candidates enhanced instructional experiences (73%), while others transformed them (27%) by developing engaging collaborative experiences that culminated in students creating a product using technology tools. Observations revealed that candidates appreciated learning how QR codes could be used to make learning experiences more engaging. Candidates showed a willingness to use their own smart devices for learning purposes. Aligning appropriate curriculum content standards with assigned tasks was achieved by all participants. 相似文献
965.
徐颂峰 《佳木斯教育学院学报》2012,(2):343-344
体育消费作为社会休闲消费的重要组成部分,是衡量社会闲暇时间和经济的重要标志,或者说是标志社会幸福程度的数据之一,进入普遍有闲的社会是人类的共同理想。随着科学技术进步,生产力的发展和社会分工的越来越细致,劳动者的劳动时间不断减少,体育锻炼在人们生活中的地位越来越重要,或者说,体育消费在人均体育资源相对短缺的都市,也凸显重要,用钱换闲,换来健康和科学合理的体育锻炼指导是一种新的城市人的需求和经济增长点。作者认为可以把体育所需要的时间及收入纳入到消费函数中进行分析。在市场行为下,时间的商品化、服务的质量和市场化程度成为体育消费在消费函数中的基本约束。 相似文献
966.
967.
In high‐school chemistry the pre‐experimental phase of inquiry cycles often remains neglected. According to a procedural model, which is described in the text, this phase begins with an observation that stimulates students’ prior factual knowledge, the formulation of a research question for further elaboration (epistemic questions), the anticipation of a hypothetical answer, and the planning of experimental steps for deciding on the hypothetical answer. These activities were explicitly prescribed in an experimental group of 28 10th‐graders. Raising the quality of students’ epistemic research questions by providing structured help was a special focus of the intervention. Hypothesised motivational and cognitive effects were measured and compared with a group of 25 students (control group) who engaged in non‐structured pre‐experimental activities. The intervention provided to the experimental group resulted in stronger preferences for a more open and non‐recipe type of experimentation, in more intense cognitive activities (thoughts), and, most importantly, in increased skills for formulating causal epistemic questions. Supporting such procedural skills in classrooms may contribute to transforming labwork into intentional activities and students into active learners by helping them focus on further elaborating their knowledge. 相似文献
968.
Oscar Espinoza 《Educational research; a review for teachers and all concerned with progress in education》2013,55(4):343-363
Background Over the past four decades there have been a number of controversies arising from the discussion of ‘equity’ and ‘equality’. These concepts are often invoked by policy analysts, policy-makers, government officials and scholars in order to justify or critique resource allocation to different levels of the educational system. Purpose By creating a new equality–equity goal-oriented model, which allows the combination of different dimensions for each concept with different stages of the educational process, this paper aims to achieve two purposes: (1) to clarify among researchers, educators, evaluators, policy analysts, and policy-makers the notions of ‘equality’ and ‘equity’; and (2) to encourage researchers and evaluators to critically examine and synthesize equality/equity-based research. Sources of evidence A review of the literature concerning the meaning, goals and assumptions of the concepts ‘equity’ and ‘equality’, and their implications for social and public policy, is presented. Main argument A survey of recent and earlier debates on ‘equity’ and ‘equality’ among scholars and researchers reveals disagreement and confusion about what those concepts really mean and what they involve in terms of goals and results. It is debatable whether we can have ‘equity’ and ‘equality’ in a society that prioritizes efficiency in resource management over social justice. Certainly, such questions have shaped and guided many discussions and theoretical debates among scholars, policy analysts and policy-makers. Conclusions Most of the definitions of ‘equity’ and ‘equality’ are frequently used by many researchers, evaluators, policy-makers, policy analysts, scholars and educators as if they were interchangeable. Instead of arguing for a unique or simple conception of ‘equity’ and ‘equality’, a set of definitions of those concepts as well as a discussion related to theoretical and policy issues associated are presented. In order to avoid that confusion, the equality–equity model developed in this paper suggests several new directions for analysis and research. It provides some ideas about how ‘equity’ (i.e. ‘equity for equal needs’, ‘equity for equal potential’ and ‘equity for equal achievement’) and ‘equality’ (i.e. ‘equality of opportunity’, ‘equality for all’ and ‘equality on average across social groups’) could be treated and measured in future research in relation to different features of the educational process (availability of resources, access, survival, output and outcome). 相似文献
969.
Single subject (SS) designs are popular in educational and psychological research. There exist several statistical techniques designed to analyze such data and to address the question of whether an intervention has the desired impact. Recently, researchers have suggested that generalized additive models (GAMs) might be useful for modeling nonlinear effects that are common with SS designs. This study sought to extend the use of GAM from SS to a research design in which individuals may be placed in separate groups and receive different interventions. Results of the simulation study found that using a mixed model form of GAM (GAMM) resulted in higher power for detecting actual effects in the population than was true for either GAM or a Bayesian GAM estimator. Thus, GAMMs are recommended for use with SS designs when interventions are expected to induce nonlinear relationships between time and the outcome variable and individuals receive different treatments. 相似文献
970.