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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   
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[目的/意义]针对当前知识发现服务中存在的个性化程度不高和推荐效果不佳等问题,提出一种基于用户兴趣度量和内容分析的推荐算法。[方法/过程]文章通过特征词分布、LDA主题分布、引文结构网络三个维度构建学术资源模型,并通过对用户行为的度量,计算用户对其浏览学术资源的兴趣度,结合学术资源模型构建用户兴趣模型。将用户兴趣模型与学术资源模型匹配,计算其相似度,得到用户对每条学术资源的兴趣值,最后将兴趣值最高的TOP-N学术资源推荐给用户。[结果/结论]通过实验检验算法的有效性和推荐准确率,结果显示,本文从实时动态度量兴趣的角度,提出的推荐算法能较好地预测用户兴趣,推荐效果显著,为实现发现服务精准推荐提供思路。  相似文献   
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Drawing on psychological ownership and social exchange theories, this study suggests theoretical arguments and empirical evidence for understanding employee reactions to distributive, procedural, and interactional (in)justice — three crucial bases of employees’ feelings of social self-worth. Utilizing field data and artificial intelligence technique, this paper reveals that distributive, procedural, and interactional (in)justice contribute to higher levels of knowledge hiding behavior among employees and that this impact is non-linear (asymmetric). By reuniting the discourses of organizational justice and knowledge management, this study indicates that feelings of psychological ownership of knowledge and the degree of social interaction are mechanisms that work with organizational (in)justice to influence knowledge hiding behavior. The current research may inform contemporary theories of business research and provide normative guidance for managers.  相似文献   
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Sentiment lexicons are essential tools for polarity classification and opinion mining. In contrast to machine learning methods that only leverage text features or raw text for sentiment analysis, methods that use sentiment lexicons embrace higher interpretability. Although a number of domain-specific sentiment lexicons are made available, it is impractical to build an ex ante lexicon that fully reflects the characteristics of the language usage in endless domains. In this article, we propose a novel approach to simultaneously train a vanilla sentiment classifier and adapt word polarities to the target domain. Specifically, we sequentially track the wrongly predicted sentences and use them as the supervision instead of addressing the gold standard as a whole to emulate the life-long cognitive process of lexicon learning. An exploration-exploitation mechanism is designed to trade off between searching for new sentiment words and updating the polarity score of one word. Experimental results on several popular datasets show that our approach significantly improves the sentiment classification performance for a variety of domains by means of improving the quality of sentiment lexicons. Case-studies also illustrate how polarity scores of the same words are discovered for different domains.  相似文献   
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ABSTRACT

The basic aim of this paper is to discuss the concept ‘Knowledge Democracy’ (KD) and what it can mean in the school context, its implications on knowledge production and dissemination and on the educational practices. We try to enrich this discussion by presenting action research projects to provide case studies of how thinking about KD can reshape educational practice. We consider that the discussion on KD has to be enriched as the concept seems very promising with good prospects towards school’s democratization. On the other hand, as it is quite new, it can encompass internal contradictions that can cause problems at the level of practice. So, we consider very important any contribution to this discussion not as another theoretical sample of the debate on the ‘politics of knowledge’, but because any improvement at the thinking of the issue can be reflected on school practices. Any challenge to traditional politics of knowledge can lead to a deeper understanding of the world of schooling and to transformations through new discourses and new approaches to teaching and learning in school.  相似文献   
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王思茗  滕广青 《图书情报知识》2020,(3):109-118,F0003
[目的/意义]领域知识的跨学科交叉研究能够打破学科间的壁垒,有助于发现重大科学问题的解决方案。[研究设计/方法]基于图书情报学领域文献题录信息构建轻量级领域知识图谱,从中提取学科信息、国家信息、时间信息及其关联,采用时间与空间相结合的多维度分析方法,对学科交叉的演化进程以及国家差异进行跟踪与分析。[结论/发现]图书情报学领域内学科交叉现象日渐显著,各国家的学科交叉程度与倾向存在差异,一些目前尚不突出的交叉学科方向值得关注。[创新/价值]采用多维度视角分析学科交叉现象,相关结论可以为国家科技战略制定及学科发展规划提供有益参考。  相似文献   
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[目的/意义] 梳理人文社科专著众筹OA出版的发展现状,分析具有公益性特点的OA出版物和具有商业性特点的众筹出版所引起的冲突,以期对学术专著众筹出版提出有价值的思考。[方法/过程] 从发起者、投资者和众筹平台3个基本要素梳理Open Book Publishers和Knowledge Unlatched的众筹模式,比较异同点,探讨两者在竞争中引起的问题。[结果/结论] 目前,欧美国家的学术专著众筹出版分为高校、众筹商和OA出版社3种模式。Knowledge Unlatched是期望通过对图书馆的优质服务获得收益的众筹商,Open Book Publishers是借助网络开展众筹出版的OA出版社,两者属于商业化大型公司和非营利性OA出版社的竞争关系,在OA出版物的商业化开发、财务公开透明、垄断性的销售模式和审核制度方面值得高度关注。  相似文献   
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Among existing knowledge graph based question answering (KGQA) methods, relation supervision methods require labeled intermediate relations for stepwise reasoning. To avoid this enormous cost of labeling on large-scale knowledge graphs, weak supervision methods, which use only the answer entity to evaluate rewards as supervision, have been introduced. However, lacking intermediate supervision raises the issue of sparse rewards, which may result in two types of incorrect reasoning path: (1) incorrectly reasoned relations, even when the final answer entity may be correct; (2) correctly reasoned relations in a wrong order, which leads to an incorrect answer entity. To address these issues, this paper considers the multi-hop KGQA task as a Markov decision process, and proposes a model based on Reward Integration and Policy Evaluation (RIPE). In this model, an integrated reward function is designed to evaluate the reasoning process by leveraging both terminal and instant rewards. The intermediate supervision for each single reasoning hop is constructed with regard to both the fitness of the taken action and the evaluation of the unreasoned information remained in the updated question embeddings. In addition, to lead the agent to the answer entity along the correct reasoning path, an evaluation network is designed to evaluate the taken action in each hop. Extensive ablation studies and comparative experiments are conducted on four KGQA benchmark datasets. The results demonstrate that the proposed model outperforms the state-of-the-art approaches in terms of answering accuracy.  相似文献   
10.
罗天强  殷正坤 《科学学研究》2016,34(9):1287-1293
自然规律是随着宇宙的演化而自然生成的,而人类能够通过自己的实践活动实现新规律的人工生成。科学实验作为科学研究的重要基础和手段,人们能够通过纯化简化实验发现自然界原本存在的自然规律,也能够通过强化激化及特殊实验和技术科学实验人工生成自然界原本不存在的新规律。人工生成新规律,改变了人与规律关系的传统认识,并使人们充分认识到在科学研究和技术开发活动中,设定新技术目标、加强实验仪器和设备的研制、加强稀有资源的研究开发与保护、加强技术科学研究等具有特别重要的意义。  相似文献   
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