首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   54941篇
  免费   1715篇
  国内免费   1054篇
教育   27101篇
科学研究   15106篇
各国文化   123篇
体育   1565篇
综合类   2150篇
文化理论   50篇
信息传播   11615篇
  2024年   24篇
  2023年   266篇
  2022年   658篇
  2021年   1145篇
  2020年   1487篇
  2019年   1175篇
  2018年   896篇
  2017年   1036篇
  2016年   1289篇
  2015年   1477篇
  2014年   2661篇
  2013年   3868篇
  2012年   4333篇
  2011年   4620篇
  2010年   3042篇
  2009年   2848篇
  2008年   3373篇
  2007年   4033篇
  2006年   4308篇
  2005年   3733篇
  2004年   3073篇
  2003年   2559篇
  2002年   2004篇
  2001年   1522篇
  2000年   889篇
  1999年   351篇
  1998年   231篇
  1997年   178篇
  1996年   131篇
  1995年   71篇
  1994年   103篇
  1993年   82篇
  1992年   97篇
  1991年   54篇
  1990年   20篇
  1989年   26篇
  1988年   5篇
  1987年   6篇
  1985年   5篇
  1984年   3篇
  1983年   2篇
  1980年   1篇
  1979年   1篇
  1976年   1篇
  1957年   23篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
With the creation of interactive tasks that allow students to explore spatial ways of knowing in conjunction with their other ways of knowing the world, we create a space where students can make sense of information as they organize these new ideas into their already existing schema. Through the use of a Common Online Data Analysis Platform (CODAP) and data from Public Use Microdata Areas (PUMA), students can explore the communities in which they live and work, critically examining opportunities and challenges within a defined space.  相似文献   
52.
Despite embracing GCED themes, the Lebanese National Curriculum faces multifaceted challenges rooted in conflict. The 1997 curriculum is still in effect with revision attempts encumbered. Interviews with 56 public school teachers in Lebanon confirm prevalent knowledge transmission practices of prescribed civics content and lack of support for progressive teaching and critical dialogue. Findings suggest few teachers prioritise GCED constructs, while most promote nationalistic citizenship notions contributing to marginalisation. Moving forward, teacher education should develop teaching practice and mindsets for sustainable GCED with the intent of emancipating teachers and students from the limitations of national curricula.  相似文献   
53.
Schools in England are expected to ‘close the gap’ for a range of vulnerable pupils who are achieving below the levels seen amongst their same-aged peers. They are also highly accountable for additional funding that is provided to support this goal. The project reported here involved collating and analysing a range of data in order to evaluate the impact of a widely used computer-assisted-reading-intervention (CARI). Sixteen primary school pupils, all of whom were identified by their school as underachieving in literacy, used the CARI daily over a five-week period. The post-intervention data showed some clear gains in reading and spelling skills for all bar one of the children. The findings are discussed in relation to the wider literatures on CARIs. The research concludes that the CARI under investigation offers a useful and cost-effective adjunct to whole-class and group reading instruction and may be particularly beneficial for supporting the learning of pupils who are struggling to consolidate the knowledge and skills covered in their regular classroom reading instruction.  相似文献   
54.
This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results.  相似文献   
55.
基于虚拟现实技术的救助船对外消防培训仿真系统   总被引:1,自引:0,他引:1  
针对救助船消防训练中存在的海况复杂,对外消防炮射流受风影响大,往往无法准确控制其射向目标区域的问题,在理想状态下射流理论的基础上探究风对射流轨迹的影响,建立自然风条件下射流轨迹的数学模型,模拟对外消防炮射流的运动情况。应用3ds Max构建船舶模型,用Unity3D构建救助船在面临大风浪、遇险船着火等状况时对外消防系统的工作场景,提出一种精确构建粒子系统轨迹的方法,使射流模型能精确体现在场景中。通过虚拟现实设备能实现救助船对外消防培训仿真系统的立体显示和人机交互,起到更好的虚拟仿真和培训效果。  相似文献   
56.
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback.  相似文献   
57.
大数据时代个人信息保护研究综述   总被引:1,自引:1,他引:0  
姜盼盼 《图书情报工作》2019,63(15):140-148
[目的/意义]通过梳理大数据时代个人信息保护的研究文献,为未来研究个人信息保护提供借鉴。[方法/过程]利用CNKI数据库,系统收集关于大数据时代个人信息保护的国内核心期刊论文,对文献的内容进行分析,归纳研究主题,并进行论述。[结果/结论]将现有的研究成果按主题分为5类:国内外实践经验研究、基本理论问题研究、个人信息保护机制探索、个人信息安全风险与应对、相关法律法规研究,评述现有研究的不足之处并对未来的研究方向提出展望。  相似文献   
58.
59.
60.
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号