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   13563篇
  免费   313篇
  国内免费   318篇
教育   7892篇
科学研究   2555篇
各国文化   11篇
体育   752篇
综合类   849篇
文化理论   22篇
信息传播   2113篇
  2024年   4篇
  2023年   103篇
  2022年   234篇
  2021年   437篇
  2020年   502篇
  2019年   471篇
  2018年   311篇
  2017年   377篇
  2016年   420篇
  2015年   484篇
  2014年   949篇
  2013年   1011篇
  2012年   883篇
  2011年   931篇
  2010年   606篇
  2009年   607篇
  2008年   717篇
  2007年   913篇
  2006年   843篇
  2005年   733篇
  2004年   633篇
  2003年   555篇
  2002年   406篇
  2001年   328篇
  2000年   236篇
  1999年   120篇
  1998年   79篇
  1997年   74篇
  1996年   58篇
  1995年   44篇
  1994年   37篇
  1993年   18篇
  1992年   18篇
  1991年   18篇
  1990年   10篇
  1989年   8篇
  1987年   1篇
  1985年   3篇
  1979年   1篇
  1976年   1篇
  1957年   10篇
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
1.
[目的/意义] 提升公民健康水平是经济社会发展到一定程度后的必然要求,健康数据协同治理体系的构建有助于从信息科学角度达成这一要求,治理体系需要以国家战略为宏观指导,全方位服务于公民健康水平提升的总体目标。[方法/过程] 通过对《"健康中国2030"规划纲要》文本精神的领会,在分析了各治理主体对健康信息治理需求的基础上,提出一种面向"健康中国2030"战略的健康数据协同治理体系,并针对关键环节提出保障措施。[结果/结论] 协调各层级、各部门与各利益主体的健康数据治理体系构建与保障,有助于在推动国家健康战略目标的同时实现健康数据的社会价值,拓展健康信息学的研究范畴。  相似文献   
2.
在抗击新型冠状病毒疫情的众多新闻报道之中,数据新闻作品及数据可视化产品表现抢眼,效果独特,影响广泛,充分体现出数据新闻在新闻事件统计、分析、研判上的独特优势。大数据工具的介入,更让数据新闻从之前的"可视化"阶段衍变进入"工具化"阶段,成为此次公共卫生报道中值得研究的新形态。  相似文献   
3.
[目的/意义] 在科研全面数据化和“十四五”规划的背景下,高校图书馆建设方向和路径对教学和科研具有重大影响,本文旨在提出图书馆智慧化转型的下一步落地和实践思路。[方法/过程] 梳理高校图书馆发展现状,解析发展新态势,以数据意识为出发点,尝试构建智慧图书馆在技术、服务、空间等方面的发展方案。[结果/结论] 智慧图书馆的建设应重点在智能设备、智慧服务平台和智慧空间上“下深功”,此外还需在馆员角色和联盟建设上深入思考。  相似文献   
4.
[目的/意义] 灰色预测法可有效处理情报研究中广泛存在的小样本数据,通过对灰色预测法在情报研究中的应用情况进行梳理,总结其在应用过程中存在的不足,为灰色预测法在情报研究中的进一步应用提供参考。[方法/过程] 通过综述情报研究中涉及灰色预测法的相关文献,从数据选取、模型构建和解决的问题等方面对情报研究中灰色预测法的应用进行概述,总结当前情报研究中灰色预测法的应用所存在的问题,并提出改进建议。[结果/结论] 在方法应用上,已有研究主要采用数列灰预测,且模型集中在单变量灰色预测模型,根据预测对象不同,灰色预测法已经在包括期刊分析、图书馆运行管理、热点主题分析及科研机构评价方面得到了很好的应用,未来可根据预测对象特点及研究目标尝试不同的灰色预测方法,扩宽灰色预测法在其他方面的情报研究问题中的应用。  相似文献   
5.
Abstract

How does a small community college library, without marketing experience or budget, advocate for its value to a campus community and its administrators? We did so by creating an engaging, bright, and easy-to-read “pocket-graphic.” In this column, we reflect on the process of shaping a multi-use product out of a mountain of data. Through research in design practices, field observations of popular information tools, and an uncomfortable step into braggadocio, we learned to articulate the successes of our library. Our “pocket-graphic” told our story, yes – but it also provoked surprise, questions (“you really have all that?”) and delight in the lesser known successes (“you really DO all that!”). In the process, we connected our students more deeply to helpful services and resources, faculty to supportive instruction, and positively changed the tone of conversation with all our stakeholders. By turning data points into selling points, we found insights and a focus that moved our own development forward, helping ourselves to define improved priorities for advancing our critical role in student success.  相似文献   
6.
This study examines the impact of the caste-class association on enrolment in elementary education in Uttar Pradesh (UP), the largest state of India. Using data from the 71st round of NSSO, with the help of a probit model, it is found that class has a stronger impact on the enrolment ratio than caste in UP. There is a strong and direct association between caste and class at the extremes of the caste system. The association between upper-caste and upper-class significantly augments the enrolment ratio, while the association between lower caste and lower class adversely affects it. However, the cross-associations at the higher side of class, i.e., lower caste with the upper class significantly augments enrolment but the association between lower class with upper-caste is found to be adversely affecting the enrolment, though some of the interaction terms are insignificant statistically. This also ensures the dominance of class effect. This pattern is observed in the case of both rural and urban UP across genders.  相似文献   
7.
Imbalanced sample distribution is usually the main reason for the performance degradation of machine learning algorithms. Based on this, this study proposes a hybrid framework (RGAN-EL) combining generative adversarial networks and ensemble learning method to improve the classification performance of imbalanced data. Firstly, we propose a training sample selection strategy based on roulette wheel selection method to make GAN pay more attention to the class overlapping area when fitting the sample distribution. Secondly, we design two kinds of generator training loss, and propose a noise sample filtering method to improve the quality of generated samples. Then, minority class samples are oversampled using the improved RGAN to obtain a balanced training sample set. Finally, combined with the ensemble learning strategy, the final training and prediction are carried out. We conducted experiments on 41 real imbalanced data sets using two evaluation indexes: F1-score and AUC. Specifically, we compare RGAN-EL with six typical ensemble learning; RGAN is compared with three typical GAN models. The experimental results show that RGAN-EL is significantly better than the other six ensemble learning methods, and RGAN is greatly improved compared with three classical GAN models.  相似文献   
8.
为给航海模拟器建立实用可靠的船舶在波浪中运动的数学模型,基于二维线性势流理论,采用多系数保角变换法对每个船舶横剖面进行高精度拟合,计算各个横剖面的水动力系数和波浪激励力,利用Visual Studio自主开发出船舶在规则波中的纵向运动数值模拟程序。为验证这个数值模拟程序的可靠性,对S175集装箱船在迎浪中运动的幅值响应因子(response amplitude operator, RAO)进行数值计算。结果表明:当弗劳德数为0.275时,RAO计算结果在大部分频率范围内与试验结果吻合良好。因此,这个数值模拟程序能准确地对船舶在波浪中的运动时历进行仿真。  相似文献   
9.
Assessing comfort of running footwear reliably is challenging. The purpose of this study was to compare the intra-rater reliability between different assessment types, to calculate intra-individual reliability scores and to evaluate the effect of rater selection based on individual reliability scores on group level reliability. Three assessment types: ranking, Visual Analogue Scale (VAS), and Likert Scale (LS) were provided twice in six separate sessions among 30 participants, who assessed comfort of five shoes after treadmill running. Spearman's rho provided an evaluation of inter-session relative reliability and typical error as a measure of absolute reliability for each assessment type. Ranking (r?=?0.70, 95% confidence interval [CI] 0.61–0.78) yielded the highest relative reliability for overall comfort, followed by VAS (r?=?0.67, 95% CI 0.56–0.75) and LS (r?=?0.63, 95% CI 0.52–0.72), with large-scale overlaps of CIs between assessment types. The same order of assessment types was found for the percentage of reliable raters (r?≥?0.7) with 60% in ranking scale, 47% in VAS and 37% in LS. Forming subgroups corresponding to the intra-individual reliability substantially increased group level reliabilities. Based on measures of relative reliability, an extreme reduction in resolution as provided by the ranking from pairwise comparisons seems to be a valuable tool in footwear comfort assessments if assessment time is of minor importance. No preference can be provided for the two investigated rating scales. Besides the assessment type, a selection of the best raters in additional reliability checks seems to be a prerequisite for further comfort-related studies.  相似文献   
10.
目的:探析短道速滑个人项目两届冬奥会及冬奥会与世锦赛体力分配策略规律差异。方法:收集整理索契、平昌冬奥会,以及2014—2017年世锦赛短道速滑个人项目相关数据,分析单圈用时、肯德尔相关系数。结果:(1)冬奥会各单项单圈用时不同程度地少于世锦赛,平昌不同程度地少于索契;(2)除2016世锦赛500 m,其他赛事均全程具有显著相关(P<0.05);(3)除索契冬奥会女子1 000 m,其他赛事均较早出现显著相关(P<0.05),平昌冬奥会男子与女子均在第7、8圈为高相关(r≥0.70);(4)平昌冬奥会1 500 m男子第12、13圈,女子第13圈为高相关(r≥0.70),两者均从第9圈开始出现显著相关(P<0.05)。结论:500 m出发位置尤为重要,高速滑行中稳固站位能力需求突出,冬奥会中对全程维持速度能力的要求逐步提高;冬奥会1 000 m与1 500 m比赛争夺有利位置战术的实施位置较以往更为靠后。  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