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1.
Collaborations in funded teams are essential for understanding funded research and funding policies, although of high interest, are still not fully understood. This study aims to investigate directed collaboration patterns from the perspective of the knowledge flow, which is measured based on the academic age. To this end, we proposed a project-based team identification approach, which gives particular attention to funded teams. The method is applicable to other funding systems. Based on identified scientific teams, we detected recurring and significant subgraph patterns, known as network motifs, and under-represented patterns, known as anti-motifs. We found commonly occurred motifs and anti-motifs are remarkably characterized by different structures matching certain functions in knowledge exchanges. Collaboration patterns represented by motifs favor hierarchical structures, supporting intensive interactions across academic generations. Anti-motifs are more likely to show chain-like structures, hindering potentially various knowledge activities, and are thus seldom found in real collaboration networks. These findings provide new insights into the understanding of funded collaborations and also the funding system. Meanwhile, our findings are helpful for researchers, the public and policymakers to gain knowledge on research(ers) evolution, particularly in terms of primordial collaboration patterns.  相似文献   
2.
Making adversarial samples to fool deep neural network (DNN) is an emerging research direction of privacy protection, since the output of the attacker's DNN can be easily changed by the well-designed tiny perturbation added to the input vector. However, the added perturbation is meaningless. Why not embed some useful information to generate adversarial samples while integrating the functions of copyright and integrity protection of data hiding? This paper solves the problem by modifying only one pixel of the image, that is, data hiding and adversarial sample generation are achieved simultaneously by the only one modified pixel. In CIFAR-10 dataset, 11 additional bits can be embedded into the host images sized 32 × 32, and the successful rate of adversarial attack is close to the state-of-the-art works. This paper proposes a new idea to combine data hiding and adversarial sample generation, and gives a new method for privacy-preserved processing of image big data.  相似文献   
3.
In text classification, it is necessary to perform feature selection to alleviate the curse of dimensionality caused by high-dimensional text data. In this paper, we utilize class term frequency (CTF) and class document frequency (CDF) to characterize the relevance between terms and categories in the level of term frequency (TF) and document frequency (DF). On the basis of relevance measurement above, three feature selection methods (ADF based on CTF (ADF-CTF), ADF based on CDF (ADF-CDF), and ADF based on both CTF and CDF (ADF-CTDF)) are proposed to identify relevant and discriminant terms by introducing absolute deviation factors (ADFs). Absolute deviation, a statistic concept, is first adopted to measure the relevance divergence characterized by CTF and CDF. In addition, ADF-CTF and ADF-CDF can be combined with existing DF-based and TF-based methods, respectively, which results in new ADF-based methods. Experimental results on six high-dimensional textual datasets using three classifiers indicate that ADF-based methods outperform original DF-based and TF-based ones in 89% cases in terms of Micro-F1 and Macro-F1, which demonstrates the role of ADF integrated in existing methods to boost the classification performance. In addition, findings also show that ADF-CTDF ranks first averagely among multiple datasets and significantly outperforms other methods in 99% cases.  相似文献   
4.
Research trends are the keys for researchers to decide their research agenda. However, only a few works have tried to quantify how scholars follow the research trends. We address this question by proposing a novel measurement for quantifying how a scientific entity (paper or researcher) follows the hot topics in a research field. Based on extended dynamic topic modeling, the degree of hotness tracing of papers and scholars is explored from three perspectives: mainstream, short-term direction, and long-term direction. By analyzing a large-scale dataset containing more than 270,000 papers and 45,000 authors in Computer Vision (CV), we found that the authors’ orientation is more in the established mainstream rather than based on incremental directions and makes little difference in the choice of long-term or short-term direction. Moreover, we identified six groups of researchers in the CV community by clustering research behavior, who differed significantly in their patterns of orientation, topic selection, and impact. This study provides a new quantitative method for analyzing topic trends and scholars’ research interests, capturing the diversity of research behavior patterns to address the phenomenon of canonical and ubiquitous progress in research fields.  相似文献   
5.
As a hot spot these years, cross-domain sentiment classification aims to learn a reliable classifier using labeled data from a source domain and evaluate the classifier on a target domain. In this vein, most approaches utilized domain adaptation that maps data from different domains into a common feature space. To further improve the model performance, several methods targeted to mine domain-specific information were proposed. However, most of them only utilized a limited part of domain-specific information. In this study, we first develop a method of extracting domain-specific words based on the topic information derived from topic models. Then, we propose a Topic Driven Adaptive Network (TDAN) for cross-domain sentiment classification. The network consists of two sub-networks: a semantics attention network and a domain-specific word attention network, the structures of which are based on transformers. These sub-networks take different forms of input and their outputs are fused as the feature vector. Experiments validate the effectiveness of our TDAN on sentiment classification across domains. Case studies also indicate that topic models have the potential to add value to cross-domain sentiment classification by discovering interpretable and low-dimensional subspaces.  相似文献   
6.
The era of big data has promoted the vigorous development of many industries, boosting the full potential of holistic data-driven analysis, yet it has also been accompanied by uninterrupted data breaches. In recent years, especially in China, data security laws and regulations have been promulgated continuously, and many of them have made clear requirements for data classification. As the support of data security initiatives, data classification has received the bulk of attention and has been hailed by all walks of life. There is a lot of valuable information contained in the issued regulations, which has already been well exploited in the research of privacy policy compliance verification, whereas few scholars have drawn on such information to guide data classification for security and compliance. As a step towards this direction, in this paper, we define two information types: one is “regulated data” mentioned in external laws and regulations, another is “non-regulated data”, indicating internal business data produced in a certain organization, and develop a novel generalization-enhanced decision tree classification algorithm called Gen-DT to classify data. In this way, data covered by the relevant data security regulatory mandates can be quickly identified and handled in full compliance as well. Furthermore, we evaluate the proposed compliance-driven data classification scheme using datasets collected from two famous universities in China and validate that our approach can achieve better performance than existing popular machine learning techniques.  相似文献   
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8.
Misinformation on social media is a nonnegligible phenomenon that causes successive adverse impacts. Numerous scholarly efforts have been devoted to automatic misinformation detection to address this problem. The effective feature is the key to achieving high identification performance. However, the effectiveness of the feature may change in different issues and time considering the manifold social contextual reasons. Most extant literature on misinformation detection does not differentiate between topics, issues or domains. Although some research compares detection across domains, they concentrate on the model's overall performance, neglecting the effectiveness of individual features. Furthermore, the comparison studies mainly incorporate single-domain issues rather than issues that cover multiple domains. It is still difficult to determine which domain's misinformation characteristics will match those of multi-dimensional issues. Since the misinformation nowadays covers multiple domains, finding robust features in misinformation detection over issues and time is an urgent research agenda. In this study, we collected datasets of two issues, climate change and genetically modified organisms (GMOs), between January 1st, 2010 and December 31st, 2020 on Weibo, manually annotated the veracity status of the posts, and compared the performance of the proposed features in identifying misinformation by applying logistic regression. The results demonstrate that (1) the predicting power of content-based features, including topic and sentiment, is relatively robust compared to user-based and propagation-based features across issues and time. (2) The feature effectiveness varied at different time points. Our findings imply that future research could consider focusing more on content-based features, especially implicit features from the content in misinformation detection. Moreover, researchers should evaluate the feature effectiveness at different time stages to improve the efficiency of misinformation detection.  相似文献   
9.
从SARS论文的组稿看编辑的信息意识   总被引:3,自引:3,他引:0  
曾星  李恩江 《编辑学报》2004,16(3):219-221
通过对SARS的组稿实践,认为编辑要具有信息搜集意识和信息传播意识.为此,编辑需要有对信息的敏锐洞察力和强烈的社会责任感,同时要转变编辑本位为受众本位.  相似文献   
10.
文章剖析了“世界记忆”的概念及其理论基础,在此基础上探讨了有关“世界记忆”的实践价值,以期促进档案学理论创新,谋求现代社会档案价值共创,档案资源共享以及全球合作的有效呈现.  相似文献   
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