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1.
ABSTRACT

This article suggests that situations in which multiple research teams are convened under similar conditions present an opportunity to discover factors that lead to productive collaboration. It argues that social network analysis of research team outputs becomes more valuable when paired with data about research participant perceptions; and that any variables used as indicators of collaboration need to be calibrated using datasets from multiple studies with cross-team comparisons. The article provides an example of the kind of methodology needed to achieve this, describing a study with data from four research teams based at an Australian university campus, reporting their research performance over four years under conditions in which many variables were controlled and with results augmented by a survey of participant perceptions. Findings from the study indicate that there were exceptions to hypothesized associations between participant perceptions of collaboration and specific social network analysis measures over co-authorship data. The article suggests that, given the methodological challenges of studying research teams in the field, multiple datasets combining findings such as those in the present study are a path towards the development of indicators of productive higher education research collaboration.  相似文献   
2.
Majority opinions are often observed in the process of social interaction in online communities, but few studies have addressed this issue with empirical data. To identify an appropriate theoretical lens for explaining majority opinions in online environments, this study investigates the skewness statistic, which indicates how many “Likes” are skewed to major comments on a Facebook post; 3489 posts are gathered from the New York Times Facebook page for 100 days. Results show that time is not an influential factor for skewness increase, but the number of comments has a logarithmic relation to skewness increase. Regression models and Chow tests show that this relationship differs depending on topic contents, but majority opinions are significant in overall. These results suggest that the bandwagon effect due to social affordance can be a suitable mechanism for explaining majority opinion formation in an online environment and that majority opinions in online communities can be misperceived due to overestimation.  相似文献   
3.
[目的/意义] 公共图书馆地理空间布局影响着读者到馆方式和成本花费,进而影响读者对图书馆访问的体验和频次。[方法/过程] 基于出行链理论和场域理论,围绕公共图书馆地理空间布局,对读者访问公共图书馆的便利性进行了解析,分析了城市公共交通和生活设施分布和公共图书馆网络布局之间的动态关系和量化评价,利用ArcGIS对苏州城市公共图书馆布局进行了案例分析。[结果/结论] 提出建立与公共交通互动关系、接入图书馆馆外空间以及延伸到读者生活圈的策略,以提升公共图书馆地理空间布局便利性。  相似文献   
4.
Recommender Systems are currently highly relevant for helping users deal with the information overload they suffer from the large volume of data on the web, and automatically suggest the most appropriate items that meet users needs. However, in cases in which a user is new to Recommender System, the system cannot recommend items that are relevant to her/him because of lack of previous information about the user and/or the user-item rating history that helps to determine the users preferences. This problem is known as cold-start, which remains open because it does not have a final solution. Social networks have been employed as a good source of information to determine users preferences to mitigate the cold-start problem. This paper presents the results of a Systematic Literature Review on Collaborative Filtering-based Recommender System that uses social network data to mitigate the cold-start problem. This Systematic Literature Review compiled the papers published between 2011–2017, to select the most recent studies in the area. Each selected paper was evaluated and classified according to the depth which social networks used to mitigate the cold-start problem. The final results show that there are several publications that use the information of the social networks within the Recommender System; however, few research papers currently use this data to mitigate the cold-start problem.  相似文献   
5.
李慧  胡吉霞 《图书情报工作》2020,64(18):114-125
[目的/意义] 针对包含单一类型知识单元的知识网络难以全面反映学科知识结构的问题,提出一种从多维度进行知识网络结构融合的方法,为学科领域知识结构挖掘提供借鉴。[方法/过程] 利用LDA及TF-IDF方法抽取学科知识单元,然后运用语义相似度和关键词共现分析方法构建3个学科知识子网络:主题网络、关键词网络和实体网络,并采用空间节点传递对齐方法对齐子网络节点,接着设计基于图卷积操作的自编码模型对知识节点进行表示,最后通过计算余弦相似度重构学科知识网络。[结果/结论] 实验部分以人工智能领域为例,构建融合主题、关键词和实体的学科知识网络并展开分析,实验结果表明,本文所提方法能有效地揭示学科领域研究内容和知识结构,为学科知识发现与组织研究提供有益参考。  相似文献   
6.
ABSTRACT

This paper examines the social construction of ‘fashionability’ – namely, what is ‘desirable’ and ‘fashionable’ – with reference to the concept ‘cultural mediators’ that foregrounds agency, negotiation and the contested practices of market actors in cultural production. It zeroes in on the cultural mediators’ attitudes and positions in the two markets by drawing on 25 in-depth interviews with industry veterans. It shows that the mediators in South Korea and China increasingly occupy hybrid occupational roles and social positions across industries and sectors yet achieve limited success in countering the status quo of Western fashion through mediation. The analysis contributes to the literature with a categorisation of seven mediation practices that shape the valuation of fashion products (i.e. ‘fashionability’) in two ways. Empirically, this categorisation illuminates how cultural mediators make reference habitually to the broader social and cultural contexts to co-construct cultural-aesthetic objects. Theoretically, it advances a cultural-economic approach to the understanding of cultural mediation and challenges the reductionist viewpoint of actor–network theory through the notion of a matrix of cultural-economic agency.  相似文献   
7.
抗阻力训练是军校体能训练常用的训练方法,而训练至肌肉失败(TMF)作为抗阻力训练中一种新兴的训练方法,已经在健身领域引起越来越广泛的关注,并已经逐步应用于专业运动员训练中。TMF在军校这类对体能要求较高的机构内具有广阔的应用前景,但现阶段TMF在军校还未得到推广,大部分军校仍然沿用过去的传统抗阻力训练模式。本文从介绍抗阻力训练与TMF的相关概念出发,分析了TMF的作用机制,提出了在军校训练中引入TMF的可行训练项目。为了进一步研究TMF对于军校学员体能训练效果的影响,本文选取成绩相近的部分学员进行分组对照实验,运用统计学方法处理实验结果,从而证明了TMF对于学员体能具有明显提升作用,最后对本次研究工作进行了总结和展望。  相似文献   
8.
为提高船舶航迹预测精度,解决准确建模难度大和神经网络易陷入局部最优的问题,考虑实时获取目标船AIS数据较少的特点,提出一种基于支持向量机(support vector machine,SVM)的航迹预测模型。选择AIS数据中的航速、航向和船舶经纬度作为样本特征变量;采用小波阈值去噪的方法处理训练数据;采用差分进化(differential evolution,DE)算法对模型内部参数寻优以提高模型收敛速度和预测精度。选取天津港实船某段航迹的AIS数据,比较基于DE-SVM与基于BP神经网络的航迹预测模型的仿真结果。结果表明,基于DE-SVM的航迹预测模型具有更高的预测精度,简单、可行、高效,且耗时少。  相似文献   
9.
为识别与评价集装化危险品物流作业的风险因素,通过鱼骨图分析法构建风险因素评价指标体系。以风险发生的概率和后果为决策变量建立基于熵权 层次分析法(analytic hierarchy process, AHP)约束的数据包络分析(data envelopment analysis, DEA)法的风险评价模型。利用熵权 AHP解决传统DEA法的权重无限性问题,利用DEA法求解风险极大、极小值并对风险因素进行评价与排序。研究发现,人员风险、包装风险达到风险极大值,集装箱风险达到风险极小值。研究得到各风险因素决策单元的风险降低比例,并根据风险因素的特点提出集装化危险品物流作业风险管理的建议。结果表明了该评价模型的适用性和评价方法的科学性。  相似文献   
10.
认知无线电是一种可用于有效缓解当前频谱资源紧张的技术,而频谱感知是认知无线电的前提。针对低信噪比情况下频谱感知性能差的问题,提出一种将信号高阶统计量、协方差矩阵特征值与神经网络相结合的合作频谱感知算法。该算法考虑到认知用户与授权用户的信道衰落情况,利用神经网络较强的多分类能力,将最大-最小特征值之比、平均-最小特征值之比以及高阶统计量作为特征参数,通过神经网络实现合作频谱感知。仿真结果表明,该算法不仅在低信噪比情况下较其他算法具有更高的频谱检测率,而且对频谱中信号的调制类型也有较高的识别率。  相似文献   
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