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1.
ABSTRACT

This forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities.  相似文献   
2.
[目的/意义]大规模在线开放课程论坛具有丰富的用户评论数据。从大量未区分的评论数据中,自动识别出知识密度较高的探索型对话并挖掘其潜在价值,对于改善教师教学质量以及提高学生知识水平具有重要影响。[方法/过程]首先利用GloVe方法训练词向量,加强对文本语义的理解,然后利用卷积神经网络自动学习文本特征,提出一种基于深度学习的探索型对话自动识别模型,并在学堂在线平台《心理学概论》课程论坛标注数据集上进行实证与对比研究。[结果/结论]实验结果显示,利用GloVe方法预训练词向量以及在训练过程中不断对词向量进行学习修正能够提高模型效果。该模型识别探索型对话的F1值为0.94,相较于传统的朴素贝叶斯方法(0.88)、逻辑斯谛回归方法(0.89)、决策树方法(0.88)以及随机森林方法(0.88)取得较大提升,具有较高的实用性和较低的学习成本。  相似文献   
3.
Recently, models that based on Transformer (Vaswani et al., 2017) have yielded superior results in many sequence modeling tasks. The ability of Transformer to capture long-range dependencies and interactions makes it possible to apply it in the field of portfolio management (PM). However, the built-in quadratic complexity of the Transformer prevents its direct application to the PM task. To solve this problem, in this paper, we propose a deep reinforcement learning-based PM framework called LSRE-CAAN, with two important components: a long sequence representations extractor and a cross-asset attention network. Direct Policy Gradient is used to solve the sequential decision problem in the PM process. We conduct numerical experiments in three aspects using four different cryptocurrency datasets, and the empirical results show that our framework is more effective than both traditional and state-of-the-art (SOTA) online portfolio strategies, achieving a 6x return on the best dataset. In terms of risk metrics, our framework has an average volatility risk of 0.46 and an average maximum drawdown risk of 0.27 across the four datasets, both of which are lower than the vast majority of SOTA strategies. In addition, while the vast majority of SOTA strategies maintain a poor turnover rate of approximately greater than 50% on average, our framework enjoys a relatively low turnover rate on all datasets, efficiency analysis illustrates that our framework no longer has the quadratic dependency limitation.  相似文献   
4.
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   
5.
ABSTRACT

This article answers the question “Are the sourcing practices in Finnish online journalism trustworthy?” Here, trustworthiness is operationalized as the fulfillment of audience expectations towards sourcing practices. To this end, expectations of young Finnish adults (aged 18–28) were compared to the observed practices of Finnish online journalists. A total of 36 news items (from 12 journalists working in three newsrooms, published in 2013 and 2017) were analyzed. The analysis indicates that online journalists’ sourcing practices largely do not conform to this audience segment's expectations. Namely, the audience expects more comprehensive investigation and thorough verification than what is common practice in online journalism. The use of high-credibility sources is both expected and commonplace. The results imply that transparency may be harmful rather than beneficial to journalism's credibility, as the unveiled practices do not always meet audience expectations.  相似文献   
6.
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   
7.
8.
Most studies on O2O services have focused solely on the technological merits of mobile applications, overlooking the role of the value systems that underlie people’s lifestyles.In contrast, this research sheds light on how people’s value systems influence their decision to adopt food delivery applications. Particularly, it proposes that people’s moral obligation in meal preparation can change the mode of thinking that guides their adoption decision. Namely, moral obligation is assumed to restrict people from acting on their basic convenience orientation in meal preparation. Empirical results have supported this assumption by showing that people with a high moral obligation (or married people) are more reluctant to convert their basic convenience-seeking tendencies into actual adoption intention than those with a low moral obligation (or single people). The important theoretical and managerial implications of these results are also discussed.  相似文献   
9.
The implementation of digital contact tracing applications around the world to help reduce the spread of the COVID-19 pandemic represents one of the most ambitious uses of massive-scale citizen data ever attempted. There is major divergence among nations, however, between a “privacy-first” approach which protects citizens’ data at the cost of extremely limited access for public health authorities and researchers, and a “data-first” approach which stores large amounts of data which, while of immeasurable value to epidemiologists and other researchers, may significantly intrude upon citizens’ privacy. The lack of a consensus on privacy protection in the contact tracing process creates risks of non-compliance or deliberate obfuscation from citizens who fear revealing private aspects of their lives – a factor greatly exacerbated by recent major scandals over online privacy and the illicit use of citizens’ digital information, which have heightened public consciousness of these issues and created significant new challenges for any collection of large-scale public data. While digital contact tracing for COVID-19 remains in its infancy, the lack of consensus around best practices for its implementation and for reassuring citizens of the protection of their privacy may already have impeded its capacity to contribute to the pandemic response.  相似文献   
10.
This study enhances the existing literature on online trust by integrating the consumers’ product evaluations model and technology adoption model in e-commerce environments. In this study, we investigate how perceived value influences the perceptions of online trust among online buyers and their willingness to repurchase from the same website. This study proposes a research model that compares the relative importance of perceived value and online trust to perceived usefulness in influencing consumers’ repurchase intention. The proposed model is tested using data collected from online consumers of e-commerce. The findings show that although trust and e-commerce adoption components are critical in influencing repurchase intention, product evaluation factors are also important in determining repurchase intention. Perceived quality is influenced by the perceptions of competitive price and website reputation, which in turn influences perceived value; and perceived value, website reputation, and perceived risk influence online trust, which in turn influence repurchase intention. The findings also indicate that the effect of perceived usefulness on repurchase intention is not significant whereas perceived value and online trust are the major determinants of repurchase intention. Major theoretical contributions and practical implications are discussed.  相似文献   
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