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41.
中国科学院珠穆朗玛大气与环境综合观测研究站(以下简称“珠峰站”)位于珠穆朗玛峰自然保护区核心区域,围绕我国青藏高原生态保护和生态文明高地建设及经济社会可持续发展的国家战略科技需求,致力于地球“第三极”复杂地形山地大气过程和环境变化研究。珠峰站以气候变化下青藏高原地-气相互作用过程研究为主线,开展了针对地表、大气、环境、冰川、生态和地球物理等过程的长期定位监测和野外科学观测试验;构建了珠峰地区多时空、多手段、高精度、多要素一体化地-气相互作用综合观测研究平台,显著提升了青藏高原特别是珠峰地区的气象观测能力。珠峰站是喜马拉雅山区地球系统科学研究的重要基地,为深入系统地开展青藏高原地球系统科学研究提供了基础数据,同时也为认识青藏高原在全球变化中的作用和对全球变化的响应提供了支撑平台。  相似文献   
42.
Laboratory-based studies show that intercultural interactions often cause people to feel stressed and anxious. However, we know fairly little about how intercultural interactions unfold outside of the laboratory. The present study examined associations between the proportion of daily intercultural interactions among 97 university students and their daily distress as well as daily well-being, using a 21-day end-of-day diary design. Overall, on days where participants had a larger proportion of intercultural interactions compared to their habitual level, they reported more psychological distress, with a small effect size. This association was similar for participants with majority status and for those with minority status. Daily proportion of intercultural interaction was unrelated to daily psychological well-being. We also observed no associations between daily intercultural interaction proportion and distress/well-being across days (using lagged analyses). This work extends laboratory-based findings that intercultural interactions are taxing to unstructured naturalistic settings.  相似文献   
43.
研究从来源、产生范式和功能特征等三个维度扩展项目间交互关系分类体系,分析交互关系视角下项目组合风险的产生和变化,在此基础上构建基于逻辑维和认识维的项目组合风险系统架构模型,并对其系统复杂性展开讨论。  相似文献   
44.
基于瑞利衍射积分公式,推导出非傍轴离轴高斯光束相干合成和非相干合成在自由空间中传输的解析公式,用所得结果对非傍轴高斯光束相干合成和非相干合成进行了研究,得到了非傍轴公式在傍轴条件下回归到傍轴理论所得结果.远场近似,轴上光强以及傍轴离轴高斯光束的相干合成与非相干合成光束传输公式可做为本文结果的特例给出.数值计算表明,合成光束的光强分布与合成方式(相干合成和非相干合成)、光束束宽w0(或等效于f参数)、光束束数M、离轴参数α以及传输距离z有关.在远场,对于相干合成光束,M束非傍轴高斯光束的合成光束的轴上光强是单束非傍轴高斯光束的轴上光强的M^2倍;对于非相干合成光束,M束非傍轴高斯光束的合成光束的轴上光强是单束非傍轴高斯光束的轴上光强的M倍。  相似文献   
45.
一种新设计的技术媒介远程教学模式理论分析框架   总被引:1,自引:0,他引:1  
本文尝试建立一种新设计的技术媒介远程教学模式理论分析框架。首先指出教育技术学和教育传播学对研究技术媒介的远程教学的理论指导意义。在分析比较人际面授教学与技术媒介教学的基础上,进一步将技术媒介教学划分成技术环境中的面授教学和技术媒介的远程教学两类,随后集中论述技术媒介的远程教学的各种模式:教学信息传输模式、远程教学交互模式、远程学习模式,以及远程教学与远程学习的时空分离模式。最后,提出并讨论新设计的技术媒介远程教学模式的理论分析框架。  相似文献   
46.
陈琳 《铜仁学院学报》2010,12(2):126-129
首先利用Fadeev-Jakiw方法对存在边界约束的旋量场进行量子化,计算电子-电子相互作用二级近似的散射矩阵,发现边界条件将引起波矢的重新分布。因而当旋量粒子存在相互作用时,作用引起的量子跃迁有的模式被限制了。  相似文献   
47.
There is surprisingly little empirical research examining issues of fidelity of implementation within the early childhood education literature. In the MyTeachingPartner project, 154 teachers were provided with materials to implement a supplemental classroom curriculum addressing six aspects of literacy and language development. The present study examines the degree of variability in three aspects of implementation fidelity – dosage, adherence, and quality of delivery – and whether these components of fidelity were associated with children's growth in language and literacy skills across the preschool year. Findings indicate that teachers reported using the curriculum fairly often (dosage) and that they were observed to generally follow curricular lesson plans (adherence). In contrast, the quality of delivery, defined as the use of evidence-based teacher–child interactions for teaching literacy and language, was much lower. Children in classrooms in which activities were observed to last for longer (dosage) and in which teachers exhibited higher quality of delivery of literacy lessons made significantly greater gains in early literacy skills across the preschool year. Also, teachers’ use of higher quality language interactions was associated with gains for children who did not speak English at home. Results have implications for teacher professional development and the supports provided to ensure that curricula are delivered most effectively.  相似文献   
48.
Introduction: Many studies in physical education (PE) have sought to identify and categorize the modes of student interaction in order to gain greater insight into the nature of cooperative activity. More others recent studies have examined how modes of interaction evolve on the basis of the modes of collective activity that they generate. These studies have shown to describe and explain the interactions among individuals and the processes they generate, which then lead to the construction, deconstruction or reconstruction of different interaction modes. Although some studies have sought to describe the dynamics of student interactions, very few have quantified these dynamics. By doing so, however, researchers might gain a new perspective on student interaction modes that inspires new designs for teaching in PE, thereby having professional impact. The present study extends this research by investigating the dynamics of student interaction, with a focus on the emergence of interaction modes during orienteering lessons. For this purpose, the study was conducted within the methodological framework of course of action theory, which is an effective approach for examining activity in natural situations to provide insight into the experience of activity from the actors perspective.

Method: The study was conducted in two classes of seventh-grade students (about 12 years old) in which 16 students volunteered and were available for post-action interviews immediately after the lessons under study. These volunteers were placed in eight affinity-based dyads. The teachers planned orienteering lessons at similar levels of difficulty and duration but modified the lessons across a range of contextual features. Two categories of data were collected: (1) data from audiovisual recordings as the students searched for the checkpoints and (2) verbalization data during the post-action interviews with the students. The data were processed in two steps: one qualitative, the other quantitative. The qualitative step consisted of processing the data of the student experiences to characterize their interactions in the three different contexts. In the quantitative step, the data from the first step were graphically represented to depict the interaction dynamics within the student dyads.

Results and discussion: The qualitative analysis showed the emergence of three modes of student interaction shared across each learning context: co-construction, confrontation and delegation. The quantitative analysis revealed the percentages of the different modes of interaction and therefore characterized the interaction dynamics. Our results showed that the interaction dynamics within the dyads were both unique and similar in the task contexts in terms of both ratios of change and distribution. Results are discussed across two major points of interest: (1) the observation of the same interaction modes whatever the context yet with quite different dynamics and (2) proposals for PE teacher interventions.  相似文献   

49.
竞技健美操托举与配合动作的创新性   总被引:1,自引:0,他引:1  
托举与配合动作作为竞技健美操艺术评判的重要内容,已凸显出特有的艺术魅力。然而在现阶段,它的创新却是制约我国竞技健美操成套艺术价值提升的瓶颈。文章论述了托举与配合动作的本质特征,采用录像观察法对近三届世界健美操锦标赛成套动作中的托举与配合动作就影响动作的空间因素、时间因素、方法因素和审美因素进行分析,指出改变与重组各因素是创新的重要方法。在创新中,时空的快速转换增添惊险性,方法的综合运用体现复杂性,造型的独特创意展示唯一性,各因素的变异与重组激发创新性。  相似文献   
50.
In this article, we present an approach for comprehensive analysis of the effectiveness of interventions based on nonlinear structural equation mixture models (NSEMM). We provide definitions of average and conditional effects and show how they can be computed. We extend the traditional moderated regression approach to include latent continous and discrete (mixture) variables as well as their higher order interactions, quadratic or more general nonlinear relationships. This new approach can be considered a combination of the recently proposed EffectLiteR approach and the NSEMM approach. A key advantage of this synthesis is that it gives applied researchers the opportunity to gain greater insight into the effectiveness of the intervention. For example, it makes it possible to consider structural equation models for situations where the treatment is noneffective for extreme values of a latent covariate but is effective for medium values, as we illustrate using an example from the educational sciences.  相似文献   
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