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1.
[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   
2.
In social networking services (SNSs), users’ unclear understanding of the large and invisible audience increases the chances of online turbulence, which is a key source of SNS-induced stress. This growing phenomenon has gained increasing attention in academia and industry due to the undesirable consequences for users and SNS platforms. In this study, we draw from the transactional model of stress to examine how audience management strategies impact online turbulence and lead to neglected unintended audience concern and lurking. We also investigate the role of self-monitoring as a stress inhibitor. We test our model with data collected from 301 SNS users. The results show that the four types of audience management strategies have different effects on online turbulence, which significantly impacts neglected unintended audience concern especially when users have high self-monitoring skills. We believe that this work contributes, both from scientific and practical standpoints, to the understanding of the interventions and stressful responses of online turbulence in SNSs.  相似文献   
3.
Cross-Company Churn Prediction (CCCP) is a domain of research where one company (target) is lacking enough data and can use data from another company (source) to predict customer churn successfully. To support CCCP, the cross-company data is usually transformed to a set of similar normal distribution of target company data prior to building a CCCP model. However, it is still unclear which data transformation method is most effective in CCCP. Also, the impact of data transformation methods on CCCP model performance using different classifiers have not been comprehensively explored in the telecommunication sector. In this study, we devised a model for CCCP using data transformation methods (i.e., log, z-score, rank and box-cox) and presented not only an extensive comparison to validate the impact of these transformation methods in CCCP, but also evaluated the performance of underlying baseline classifiers (i.e., Naive Bayes (NB), K-Nearest Neighbour (KNN), Gradient Boosted Tree (GBT), Single Rule Induction (SRI) and Deep learner Neural net (DP)) for customer churn prediction in telecommunication sector using the above mentioned data transformation methods. We performed experiments on publicly available datasets related to the telecommunication sector. The results demonstrated that most of the data transformation methods (e.g., log, rank, and box-cox) improve the performance of CCCP significantly. However, the Z-Score data transformation method could not achieve better results as compared to the rest of the data transformation methods in this study. Moreover, it is also investigated that the CCCP model based on NB outperform on transformed data and DP, KNN and GBT performed on the average, while SRI classifier did not show significant results in term of the commonly used evaluation measures (i.e., probability of detection, probability of false alarm, area under the curve and g-mean).  相似文献   
4.
Data from China demonstrate that the effect of the number of siblings on education is restricted by many factors, such as children’s gender, urban or rural household registration, whether there is only one child, the birth order of children within the family, and parents’ status. Chinese families have significant preferences for the eldest son and the youngest son. Moreover, research based on the natural experiment and instrumental variable approach suggests that market-oriented reform of education has increased the cost of family education expenditures since China’s reform and opening up, which further aggravates the negative impact on education of having many siblings in an urban setting.  相似文献   
5.
This study investigates the factors determining children's educational attainment, focusing on gender-differential intergenerational patterns, by employing a case study from rural Mindanao. The result mainly shows, unlike general trends in developing countries, educational attainment is more favorable for girls; maternal education level is equally associated with daughters’ and sons’ education levels, and paternal education level is preferentially favorable to their sons. To reduce the disparity, suggestions include providing boy-specific interventions to enhance the magnitude of the father–son educational virtuous circle and comparing the magnitude of gender-equal maternal and boy-preferential paternal education influences to specify which effect is larger.  相似文献   
6.
文章旨在通过对OCW和MOOC所采用的教学方式的对比,探索开放在线课程在由"重资源"向"重服务"变革的过程中,其教学方法所发生的适应性变化。文章通过四个常用的开放在线课程搜索引擎,随机抽样出51门OCW课程和51门MOOC课程作为研究样本,并从课程说明中获取课程周数、建议学时、学习方式、教学手段等信息。结果表明:与OCW相比,MOOC建议以较短的周数、每周投入较多的时间来完成课程,以提高课程完成率;少量课程采用了基于项目、基于研究和基于团队的学习方式,但MOOC环境下的在线协作学习仍存在难度;在线论坛和讲座视频是MOOC中使用较多、发展较成熟的教学手段;社会媒体和位置地图等则是OCW中未出现而在MOOC中发展形成的。最后,文章根据研究结果提出了相应的教学建议。  相似文献   
7.
嵌入班级网络中的大学生在交往中形成不同的小群体,这些小群体间的学业成就是否具有显著性差异?研究者将社会网络分析方法中的整体网分析与元分析(Meta分析)相结合,在对大学生班级内小群体的学业成就差异进行多项独立研究的基础上,运用元分析技术将29项研究(N=1076)的结果予以综合分析,得到如下结论:(1)每个班级的大学生都在互动过程中形成了不同数量的小群体,且每个小群体中的学生数量不同;(2)大学生学业成就存在着“人以群分”现象,即同一班级的大学生在互动中产生的小群体在学业成就上存在显著性差异。因此,大学生应加强与高学业成就水平的小群体之间的互动以提高学业成就;而高校管理者也应采用科学的方法识别班级中的不同小群体,从而采取相应的学业成就提升策略。  相似文献   
8.
区域创新系统外生结构性风险的识别及其解耦分析   总被引:1,自引:0,他引:1  
基于对区域创新系统(RIS)的理论回顾,指出了忽视RIS的外生性风险管理是部分地区区域创新系统衰退的重要原因.提出了区域创新系统外生结构性风险的概念和因素构成,给出了各要素之间的耦合关系,基于管理熵进一步构建了该耦合关系的量化描述模型,为区域创新系统外生结构性风险管理走向实用化奠定了基础.  相似文献   
9.
Despite the recognized value that mobile BI (m-BI) brings to firms, our understanding of the use of m-BI and its determinants are limited. In this study, we suggest that m-BI system quality characteristics may be among the factors that influence m-BI use. Yet, in the information systems (IS) literature there is mixed support for the relationship between system quality and system use at the individual level. Given there is research suggesting that engaged users are an indication of the technology’s success, we believe that ‘engagement’ may be the key to understanding the relationship discrepancy between system quality and use. To address this gap, we conducted a quantitative study of key informants who use m-BI, to understand what the key m-BI capabilities are and other success dimensions perceived as important by users. The results indicate that m-BI system quality attributes affect m-BI use indirectly through engagement, with this finding contributing to understanding of the complexity of IS use in mobile technologies.  相似文献   
10.
Research and development activities are regarded as one of the most influencing factors of the future of a country. Large investments in research can yield a tremendous outcome in terms of a country’s overall wealth and strength. However, public financial resources of countries are often limited which calls for a wise and targeted investment. Scientific publications are considered as one of the main outputs of research investment. Although the general trend of scientific publications is increasing, a detailed analysis is required to monitor the research trends and assess whether they are in line with the top research priorities of the country. Such focused monitoring can shed light on scientific activities evolution as well as the formation of new research areas, thus helping governments to adjust priorities, if required. But monitoring the output of the funded research manually is not only very expensive and difficult, it is also subjective. Using structural topic models, in this paper we evaluated the trends in academic research performed by federally funded Canadian researchers during the time-frame of 2000–2018, covering more than 140,000 research publications. The proposed approach makes it possible to objectively and systematically monitor research projects, or any other set of documents related to research activities such as funding proposals, at large-scale. Our results confirm the accordance between the performed federally funded research projects and the top research priorities of Canada.  相似文献   
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