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141.
Unfinished and ongoing exploration, Oil Painting, 1.30?*?1?m, September 2015.  相似文献   
142.
Mixing examples of different categories (interleaving) has been shown to promote inductive learning as compared with presenting examples of the same category together (massing). In three studies, we tested whether the advantage of interleaving is exclusively due to the mixing of examples from different categories or to the temporal gap introduced between presentations. In addition, we also tested the role of working memory capacity (WMC). Results showed that the mixing of examples might be the key component that determines improved induction. WMC might also be involved in the interleaving effect: participants with high spans seemed to profit more than participants with low spans from interleaved presentations. Our findings have relevant implications for education. Practice schedules should be individually customised so society as a whole can profit from differences between learners.  相似文献   
143.
This article describes a three‐year project undertaken at Pear Tree School for children and young people with severe and multiple and profound learning difficulties. Lesley Sullivan, the school's head teacher, believed that much of the value within the work of this outstanding school went unidentified by existing approaches to planning, monitoring and evaluation. Richard Crombie, educational psychologist, was engaged to work on the project. Also involved were Kate Walker and Rebecca Warnock, deputy head teachers, as well as the whole staff, children and some parents. The project takes as its starting point that essential, but very often unnoticed and unconscious, professional practice is rooted in implicit processes learnt experientially. We set ourselves the task of finding meaningful frameworks for identifying and developing that practice. This meant close observation within and outside school coupled with feeding back to staff, and their subsequent engagement with and use of explanatory frameworks.  相似文献   
144.
任务卸载是雾计算的主要技术之一,即计算能力不足的节点将任务卸载给具有富余资源的节点帮助计算。以优化任务平均卸载时延和提升卸载服务成功率为目标,利用多臂老虎机理论为动态雾计算网络提出一种基于在线学习的任务卸载算法,可实时做出最优卸载决策。将该算法扩展到非稳定网络状态,使之可以动态追踪网络中节点的资源与环境变化,实时调整卸载决策。详细分析所提出算法的性能、复杂度和存储占用情况。仿真结果表明,这两种算法可达到的长期平均任务卸载时延均十分接近理想算法下的最优时延,卸载服务成功率也得到显著提升。此外,所提算法在非稳定的网络状态下能够追踪到计算资源与环境的变化。  相似文献   
145.
准确提取钢铁厂对去产能监测和环境保护具有重要意义。传统的人工目视解译方法效率低、成本高,无法满足开展大区域钢铁厂监测的需求。以深度学习目标检测网络SSD为基础,构建面向遥感影像钢铁厂提取的深度学习目标检测网络,提出maxout模块,将负样本通路优化为多分支结构,突出难分负样本特征并提升网络对无用特征的抵制效果。利用国产GF-1数据对京津冀地区的钢铁厂进行快速自动提取实验。与人工解译的钢铁厂点位数据的对比表明,该目标检测方法的提取精度达到80%以上。  相似文献   
146.
鉴于船舶在波浪中的六自由度运动中,其升沉、横摇和纵摇运动对船舶工作平台上的设备影响较大,设计一种三自由度并联式波浪补偿平台来减少这种影响。通过对平台进行运动学分析,得到平台的运动学模型。利用ADAMS和Simulink建立带有控制系统时间延迟参数的虚拟样机模型,依据平台的运动学模型设计对船舶运动进行补偿的控制策略,并利用虚拟样机进行仿真,验证平台机构和相应控制策略对船舶运动的补偿效果。结果表明:当控制系统的时间延迟参数取值为1 ms时,平台对船舶升沉、横摇和纵摇运动的补偿效果分别为88.81%、95.44%和91.97%;当控制系统的时间延迟参数取值为0.1 ms时,平台对船舶升沉、横摇和纵摇运动的补偿效果分别为96.04%、99.07%和97.65%。由此可见:平台对误差有一定的包容性;可利用具有船舶运动预测功能的算法为平台提供超前的船舶运动数据或者提高控制系统的实时性来提高补偿效果。  相似文献   
147.
This paper reports on a case study involving a strategic and innovative approach to creation of an in-house multifaceted digital engineering platform (the DEP) in overcoming a number of organisational problems at a multinational engineering company. The DEP was to be used strategically for simplifying the operational complexity and to create and appropriate new work-related mind-set and new organisational discourse to achieve homogenous working across the organisation, which is a huge challenge. The need for this system emerged from the need to resolve many organisational services related problems that carried phenomenal amount of processes, health and safety risks and to regulate, and, control the running of engineering project. Research data were collected using a longitudinal case study approach over a period of six months. In order to make sense of how the DEP helped the organisation, the study used certain elements of Extended Structuration Theory as a lens to assess the case study. This research discovered that the DEP succeeded in creating and appropriating work-related mind-set and organisational discourse. It also had real influence on working processes and employees at all levels while encouraging transparency, responsiveness, agility and accountability. It continues to help the organisation to govern, manage and maintain good standard of service but many barriers still remain.  相似文献   
148.
目的:探讨初学者在足球踢球动作技能学习过程中是否存在背景干扰效应,并分析原因。方法:以足球脚背内侧踢定位球动作技能作为学习任务,选取某大学足球专修班的33名学生为研究对象,分成对照组和两个实验组,进行10周的体育教学现场实验,对一周后保持测试的达标和技评成绩进行单因素方差分析。结果:三组保持测试的达标和技评成绩均值,在0.05水平上差异不具有显著性。结论:实验结果未能出现背景干扰效应,未能验证本研究提出的研究假设和背景干扰效应假说的最主要原因是,足球脚背内侧踢定位球的复杂性任务特征。  相似文献   
149.
As methods for automated scoring of constructed‐response items become more widely adopted in state assessments, and are used in more consequential operational configurations, it is critical that their susceptibility to gaming behavior be investigated and managed. This article provides a review of research relevant to how construct‐irrelevant response behavior may affect automated constructed‐response scoring, and aims to address a gap in that literature: the need to assess the degree of risk before operational launch. A general framework is proposed for evaluating susceptibility to gaming, and an initial empirical demonstration is presented using the open‐source short‐answer scoring engines from the Automated Student Assessment Prize (ASAP) Challenge.  相似文献   
150.
The focus of this paper is on a group of pupils with reading and writing difficulties who have been participating in an intervention study using assistive technology. That intervention study contained supervised training sessions with reading and writing tasks using an iPad with special supportive applications. The current study is a qualitative investigation of whether there has been any transfer from the intervention, to the pupils’ everyday school activities. Interviews with pupils and their teachers and observations during classroom lectures have been used to collect data. The results show that the pupils were positive to the assistive technology (the applications on the iPads), they found the apps easy to learn how to use and they appreciated the benefits they could give. Even so, only a few of the pupils had found use for and continued to use the tools after the intervention period finished. Possible reasons are that when the novelty wore off, students reverted to their usual study habits and that older students with many teachers and different classrooms were less able to adapt to using the apps. To improve transfer, it is suggested to introduce assistive technology earlier to students, in the younger grades, before study habits have been formed and to inform teachers about the use of AT in the classroom, including what is available and how it can benefit students.  相似文献   
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