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71.
Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face‐to‐face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology instruction model with four face‐to‐face classes that supplemented online recorded lectures was used. One instructor delivered the lectures face‐to‐face in 2007 and by online videos in 2008–2009, while a second instructor provided the supplemental face‐to‐face classes in 2008–2009. The same embryology learning objectives and selected examination questions were used for each of the three years. This allowed direct comparison of learning outcomes, as measured by examination performance, for students receiving only face‐to‐face embryology instruction versus the hybrid approach. Comparison of the face‐to‐face lectures to the hybrid approach showed no difference in overall class performance on embryology questions that were used all three years. Moreover, there was no differential effect of the delivery method on the examination scores for bottom quartile students. Students completed an end‐of‐course survey to assess their opinions. They rated the two forms of delivery similarly on a six‐point Likert scale and reported that face‐to‐face lectures have the advantage of allowing them to interact with the instructor, whereas online lectures could be paused, replayed, and viewed at any time. These experiences suggest the need for well‐designed prospective studies to determine whether online lectures can be used to enhance the efficacy of embryology instruction. Anat Sci Educ 7: 234–241. © 2013 American Association of Anatomists.  相似文献   
72.
Research suggests that massive open online course (MOOC) students prefer to study in groups, and that social facilitation within the study groups may render the learning of difficult concepts a pleasing experience. We report on a longitudinal study that investigates how co-located study groups watch and study MOOC videos together. The study was conducted with on-campus flipped classroom students. Our subjects reported an overall high satisfaction with the study group style. The research reveals that students like to stay synchronized in the group while watching MOOC videos. However, they have to find a balance between synchronization, video interaction, and the amount of conversation. Watching MOOCs on a shared display addresses the need of synchronicity, and the distribution of control can increase the video interactivities.  相似文献   
73.
随着视频编码技术的发展,视频输入参数的维度在不断的增加,使得视频编码软件变的测试面临很大的挑战。对于多维输入的软件测试,测试的效率是一个重要的衡量指标。基于自适应随机测试(ART)在多维测试领域的优点。本文分析了视频编码测试遇到的问题,并通过算法的比较分析,最后给出了自适应随机算法IDI-FSCSART在视频编码测试中的应用。  相似文献   
74.
本文调查研究了北京中关村软件业、动漫业、数字出版业和数字影音业等高端创意产业的核心技术研发和应用现状,分析了其技术创新能力。通过对比研究英、美、日等发达国家在该行业的前沿技术进展,研判中关村的行业核心技术在国内外的地位,认为中关村高端创意产业的核心技术尽管国内竞争优势明显,但与国际顶尖技术水平相比还存在较大的差距。文章最后总结了中关村现阶段技术需求重点,提出缩短技术差距的对策措施。  相似文献   
75.
分析了线性选择方法的两个缺陷,提出了一种基于聚集密度的非线性自适应选择方法。算法基本思想是:首先将每代种群划分成Pareto劣解集和Pareto非劣解集,然后依照个体的聚集密度分别在劣解集和非劣解集中构造一种偏序集,分别按照不同的等概率在这两个偏序集中选择个体,其中劣解偏序集的个体选择概率远小于非劣解偏序集的个体选择概率,根据两个偏序集中的容量自动计算出两个选择概率。这种非线性选择方法既体现了劣解集和非劣解集中个体的绝对平等性及非劣解集对劣解集的相对优先选择权,又充分考虑到了Pareto最优解的分布性。理论分析和数值计算表明,这种新的选择机制不仅能改善排序选择法的收敛性,而且能得到分布性良好的Pareto最优解。  相似文献   
76.
The Microsoft Xbox One Kinect? (Kinect V2) contains a depth camera that can be used to manually identify anatomical landmark positions in three-dimensions independent of the standard skeletal tracking, and therefore has potential for low-cost, time-efficient three-dimensional movement analysis (3DMA). This study examined inter-session reliability and concurrent validity of the Kinect V2 for the assessment of coronal and sagittal plane kinematics for the trunk, hip and knee during single leg squats (SLS) and drop vertical jumps (DVJ). Thirty young, healthy participants (age = 23 ± 5yrs, male/female = 15/15) performed a SLS and DVJ protocol that was recorded concurrently by the Kinect V2 and 3DMA during two sessions, one week apart. The Kinect V2 demonstrated good to excellent reliability for all SLS and DVJ variables (ICC ≥ 0.73). Concurrent validity ranged from poor to excellent (ICC = 0.02 to 0.98) during the SLS task, although trunk, hip and knee flexion and two-dimensional measures of knee abduction and frontal plane projection angle all demonstrated good to excellent validity (ICC ≥ 0.80). Concurrent validity for the DVJ task was typically worse, with only two variables exceeding ICC = 0.75 (trunk and hip flexion). These findings indicate that the Kinect V2 may have potential for large-scale screening for ACL injury risk, however future prospective research is required.  相似文献   
77.
Adaptive progressive download based on the MPEG-4 file format   总被引:1,自引:0,他引:1  
In this paper we describe how progressive download and adaptive streaming can be combined into a simple and efficient streaming framework. Based on the MPEG-4 file format (MP4) we use HTTP for transport and argue that these two components are sufficient for specifying an open streaming architecture. The client selects appropriate chunks from the MP4 file to be transferred based on (1) the header information (i.e. the "moov" box) in the first part of the file and (2) his observation of network throughput. The framework is completely client driven which allows for better server scalability and reduces signalling overhead. We discuss architecture and implementation issues such as complexity, interoperability and scalability and compare to 3GPP PSS Re1-6 adaptive streaming when appropriate. Measurements from a simple MP4/HTTP streaming client are presented showing that appropriate chunks are selected such that increased reliability is achieved.  相似文献   
78.
结合近几年对Premiere视频编辑技术教学改革实践,分析了专业课程教学和岗位综合技能的关系,提出将课程教学拓展为岗位教学,以项目为载体,加强学生岗位技能训练,缩短课堂教学与岗位需求之间的距离。  相似文献   
79.
现代设备复杂系数的不断提高,导致对设备维修技术专家的需求日益增大。基于网络视频的设备远程维修系统的出现,为缓解设备维修技术力量短缺的矛盾提供了新的解决方式。  相似文献   
80.
信息媒体数字视频图书馆(TheINFORMEDIADigitalVideoLibrary,简称IDVL)项目是美国数字图书馆创始计划(DigitalLibrariesInitiative,简~,DLI)最初的六个项目之一,由卡内基·梅隆大学于1994年创建。该项目一直在深入地开发数字视频及其相关技术和工具,致力于建立一个庞大的在线数字视频图书馆,为用户提供多媒体信息服务。文章对该数字图书馆的项目概况、资源组织、技术特征和服务特点等进行了综合介绍和评价。  相似文献   
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