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Abstract

In this article, we study how mountain guiding was organized and regulated in Scandinavia and the Alps between 1820 and 2015 and focus on the most important differences and similarities in Scandinavia, and between Scandinavia and the Alps. We conclude that Switzerland and Chamonix (France) represent two different systems in the Alps during the nineteenth century. However, through the emergence of national and international guide unions the regulation of mountain guiding in the Alps today appears unified, with a close connection between national regulation and mountain guide unions. In Scandinavia, Norway and Sweden historically had similar practices organizing and regulating mountain guiding, where a relatively strong layman tradition emerged during the 1960s and 1970s. In 2008, legal decisions led Sweden to change its system to match the Alp model, while Norway held on to the layman tradition. This leaves mountain guiding in Norway as a distinctly less regulated field than in France, and Switzerland, as in and Sweden.  相似文献   
43.
Maximal oxygen uptake VO(2max)) is considered the optimal method to assess aerobic fitness. The measurement of VO(2max), however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdot]O(2max) and maximal power output in 247 children (139 boys and 108 girls) aged 7.9-11.1 years. Maximal oxygen uptake was measured by indirect calorimetry during a maximal ergometer exercise test with an initial workload of 30 W and 15 W x min(-1) increments. Maximal power output was also measured. A sample (n = 124) was used to calculate reference equations, which were then validated using another sample (n = 123). The linear reference equation for both sexes combined was: VO(2max) (ml x min(-1)) = 96 + 10.6 x maximal power + 3.5 . body mass. Using this reference equation, estimated VO(2max) per unit of body mass (ml x min(-1) x kg(-1)) calculated from maximal power correlated closely with the direct measurement of VO(2max) (r = 0.91, P <0.001). Bland-Altman analysis gave a mean limits of agreement of 0.2+/-2.9 (ml x min(-1) x kg(-1)) (1 s). Our results suggest that maximal power output serves as a good surrogate measurement for VO(2max) in population studies of children aged 8-11 years.  相似文献   
44.
Propulsion, one of the most important factors in front crawl swimming performance, is generated from both the upper and lower limbs, yet little is known about the mechanisms of propulsion from the alternating movements of the lower limbs in the flutter kick (FK). The purpose of this systematic review was to review the literature relating to the mechanisms of propulsion from FK in front crawl. There was limited information about the mechanisms of propulsion in FK. Since movements of the lower limbs are similar between FK and the dolphin kick (DK), mechanisms of propulsion from DK were reviewed to better understand propulsion from FK. Recent evidence suggests that propulsion in DK is generated in conjunction with formation and shedding of vortices. Similar vortex structures have been observed in FK. Visualisation and simulation techniques, such as particle image velocimetry (PIV) and computational fluid dynamics (CFD), are non-invasive tools that can effectively model water flow without impacting swimming technique. These technologies allow researchers to estimate the acceleration of water and, consequently, the propulsive reaction forces acting on the swimmer. Future research should use these technologies to investigate propulsion from FK.  相似文献   
45.
The aims of this study were to examine the release speed of the ball in maximal instep kicking with the preferred and the non-preferred leg and to relate ball speed to biomechanical differences observed during the kicking action. Seven skilled soccer players performed maximal speed place kicks with the preferred and the nonpreferred leg; their movements were filmed at 400 Hz. The inter-segmental kinematics and kinetics were derived. A coefficient of restitution between the foot and the ball was calculated and rate of force development in the hip flexors and the knee extensors was measured using a Kin-Com dynamometer. Higher ball speeds were achieved with the preferred leg as a result of the higher foot speed and coefficient of restitution at the time of impact compared with the non-preferred leg. These higher foot speeds were caused by a greater amount of work on the shank originating from the angular velocity of the thigh. No differences were found in muscle moments or rate of force development. We conclude that the difference in maximal ball speed between the preferred and the non-preferred leg is caused by a better inter-segmental motion pattern and a transfer of velocity from the foot to the ball when kicking with the preferred leg.  相似文献   
46.
Task orientation is currently a prominent concept under discussion in primary school didactics. It focuses on tasks along which pupils acquire competences on distinct levels of competence. The qualitative empirical study TAPSE (Textbook Analysis in Primary Science Education) pursues the question which conception of task orientation is present in current textbooks in primary science education. The study follows two foci: (a) The introduction of a new category system for the analysis of the task-orientation potential of tasks, based on the further development of existing category systems for analyzing tasks; and (b) the analysis of 994 task statements in science textbooks with respect to the didactic quality of their task orientation. The sample included nine primary science textbooks, four from Germany, and five from Luxembourg. Textbooks were selected from the most frequently sold series in the respective country. All tasks of the textbooks were analyzed deductively and inductively by four coders in three steps: (a) Identifying tasks with task-oriented potential; (b) itemizing different types of task-orientation potential; and (c) comparing the textbooks with respect to country- and period-specific manifestations of task orientation. Analysis indicated that (a) there are few tasks which meet the criteria of task orientation; (b) distinct types of task orientation can be generated, among which implicit forms dominate; and (c) differences occur in the characteristics of task orientation between older and newer textbooks as well as between German and Luxembourgish ones. Central points of discussion ensue from this: The need to develop models for social and cognitive activation for tasks, challenges for professional development for teachers, and support for pupils—in particular high achieving heterogenization.  相似文献   
47.
Structured talent identification and development, it has been argued, is one of the foundations of international sporting success and many modern elite sport systems have applied normative talent development (TD) models. The success of Norwegian handball, however, is based on an alternative approach to TD. Norwegian handball is characterized by a heterarchical organizational structure in which several key actors function highly autonomously. The aim of this article is three-fold: (a) to describe the organization of TD in Norwegian handball, (b) to identify how the inherent organizational characteristics of Norwegian handball have influenced the TD processes used and (c) to discuss if contemporary TD models provide an adequate conceptualization of the model used in Norwegian handball. This case study includes three units of analysis: (i) the overall organizational structure of Norwegian handball, (ii) the characteristics of the key actors involved and (iii) the inter-communication and collaborations of the key actors. The data sources were (a) documents and (b) interviews with 11 key informants. The informants were selected strategically to represent experienced coaches and professionals from multiple organizational units. The National Handball Federation uses a broad-based model for TD: 23% of male handball players and 15% of female handball players from the age of 13–17 years participate in regional-level initiatives in addition to practising daily in community-based volunteer sport clubs and sport schools. Findings reveal that the broad base of TD initiatives creates multiple access points to the talent pipeline for adolescents. However, because the heterarchical structure involves many actors, the unintended consequences are often related to (im)properly managing training and competition loads. There is a need therefore for well-developed coordination mechanisms and good communication between the key actors involved.  相似文献   
48.
Most science educators spend much of their time planning and teaching science methods classes yet there is very little dialogue among science educators concerning what ought to be taught. This study involved a small sample. Readers should think of it as a model for conducting similar self-studies. The instructor of this course has been teaching it since 1966, and each year, he has revised 10–20% of it. These data show that some, but not all, of the revisions have resulted in improvement. This analysis illustrates how helpful the perceptions of methods students can be for initiating and continuing a dialogue among educators regarding the structure of methods courses. Although the question of “What ought to be taught?” has been clarified to a degree, it has and always will remain.  相似文献   
49.
Studies in the history of science and education have documented that the reception and understanding of evolutionary theory is highly contingent on local factors such as school systems, cultural traditions, religious beliefs, and language. This has important implications for teaching evolution in primary and secondary schools. No universal strategy can be applied in overcoming the barriers of learning that exist and that are part of the practical and daily life in classrooms all over the world. In light of this, a huge challenge is to make high standard teaching materials fit to specific target audiences readily available. As more and more schools require teachers to use low cost or free web-based materials, in the research community we need to take seriously how to facilitate that demand in communication strategies on evolution. This article addresses this challenge by presenting the learning experience of making a digital archive of Danish Darwin editions that marked the beginnings of a series of public engagement and teaching initiatives including, among other things, comprehensive new websites, exhibits, lecture series, television documentaries, and a computer game.  相似文献   
50.
Journal of Science Teacher Education -  相似文献   
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