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991.
文章旨在通过对OCW和MOOC所采用的教学方式的对比,探索开放在线课程在由"重资源"向"重服务"变革的过程中,其教学方法所发生的适应性变化。文章通过四个常用的开放在线课程搜索引擎,随机抽样出51门OCW课程和51门MOOC课程作为研究样本,并从课程说明中获取课程周数、建议学时、学习方式、教学手段等信息。结果表明:与OCW相比,MOOC建议以较短的周数、每周投入较多的时间来完成课程,以提高课程完成率;少量课程采用了基于项目、基于研究和基于团队的学习方式,但MOOC环境下的在线协作学习仍存在难度;在线论坛和讲座视频是MOOC中使用较多、发展较成熟的教学手段;社会媒体和位置地图等则是OCW中未出现而在MOOC中发展形成的。最后,文章根据研究结果提出了相应的教学建议。 相似文献
992.
Katemari Rosa 《Cultural Studies of Science Education》2018,13(4):1005-1013
This forum paper dialogues with Sheron Mark’s A bit of both science and economics: a non-traditional STEM identity narrative. In her paper, she discusses the development of a Science, Technology, Engineering, and Mathematics (STEM) identity by a young African American male during an informal STEM for Social Justice Program. Here, the discussion focuses on Black masculinities, identity formation, and the role of science educators in making STEM fields a welcoming place for young Black men. Drawing from Mark’s data and discussion, this paper is a dialogue between science identity possibilities in the United States and in Brazil when we look at the intersections of race, gender, and socioeconomic status. Using the shared colonial past of both countries a connection is established to address race relations within science education. The main argument in this paper is that racism can no longer be denied and dismissed by the science education community worldwide and that intersectional approaches are needed to face this issue. 相似文献
993.
Research in non-equalization machining method for spatial cam 总被引:1,自引:0,他引:1
Many kinds of devices with cam have been widely used in various mechanical equipments. However, non-equalization machining for spatial cam trough remains to be a difficult problem. This paper focuses on the analysis of running conditions and machining processes of spatial cam with oscillating follower. We point out the common errors in the biased distance cutting. By analyzing the motion of oscillating follower of spatial cam, we present a new 3D curve expansion model of spatial cam trough-outline. Based on this model, we have proposed a machining method for trochoidal milling with non-equalization diameter cutter. This new method has led to a creative and effective way for non-equalization diameter machining for spatial cam with oscillating follower. 相似文献
994.
The role of conceptual conflict in conceptual change and the design of science instruction 总被引:9,自引:0,他引:9
Conceptual conflict has long been recognized as a factor that could facilitate student learning. Due, however, to the lack of a convincing explanation of why it occurs, and how it can be resolved, it has seldom been used in instructional design. Its potential use in instruction is particularly relevant in the light of the recent, well-documented finding that students' existing conceptions frequently constitute a barrier to effective learning. This article examines conceptual conflict in the light of an epistemological model of learning as conceptual change. This analysis shows that the conceptual change model provides an explanation of conceptual conflict which is sufficiently detailed to allow it to be used in the design of instruction. The results of two studies, the first of which addressed the concepts of mass, volume, and density, and the second, the concept of speed, show that instruction, designed in this way, is effective in changing students' existing conceptions. 相似文献
995.
996.
997.
John W. Borchardt 《Research quarterly for exercise and sport》2013,84(2):258-264
Abstract Ages, heights, weights, and 24 static (cable tensiometer) strength test scores were obtained from 81 college men enrolled in service course classes at the University of Oregon during the 1963–64 academic year. Of the 276 intercorrelations between strength scores, 215 were significant (p > .01; r ≥ .285). In general, when age, height, and weight were held constant, the intercorrelations between the strength scores from the different segments of the body were not greatly changed from those of the zero-order correlations between the same strength scores. Five functional clusters or groupings of strength were isolated and identified by means of the application of cluster analysis to the intercorrelations between the strength tests and by an analysis of muscle actions involved in the performance of each of the strength tests. The findings in this study disclosed five clusters or groupings of strength which were specific to shoulder, trunk, neck, wrist, and hip joints. They could also be described as arm and forearm strength, trunk strength, neck strength, hand strength, and thigh and leg strength. 相似文献
998.
Robert W. Powell 《Learning & behavior》1974,2(3):185-188
Neither domesticated hooded rats nor wild black rats responded appreciably for water on a CRF schedule when free water was available. However, four out of five crows showed substantial responding for food in the presence of identical free food. Previous reports also indicate that type of reinforcer and species are variables which significantly influence this phenomenon. Nevertheless, the overall findings seem to be amenable to an explanation based upon incentive-motivation theory. 相似文献
999.
1000.
Peer collaboration is a pedagogical method currently used to facilitate learning in classrooms. Similarly, computer-learning environments (CLEs) are often used to promote student learning in science classrooms, in particular. However, students often have difficulty utilizing these environments effectively. Does peer collaboration help students learn with these environments? Little research looking closely at face-to-face peer collaboration with computer learning environments exists. Utilizing a social-cognitive theoretical framework, this study investigated the relation between the conceptual-knowledge learning and the collaborative regulatory behaviors of students working with a peer as they studied about the human circulatory system using a hypermedia CLE. Fifty-four high-school students from the East Coast of the United States were audiotaped to identify the collaborative regulatory behaviors they evidenced as they studied. Results revealed significant correlations among students’ proportion of categories of regulatory behaviors and their learning gains (from pretest to posttest). Moreover, qualitative analyses revealed particular behaviors that larger-gain collaborative pairs engaged in to a greater extent than smaller-gain pairs as they learned with the hypermedia environment. 相似文献