Questioner or question: Predicting the response rate in social question and answering on Sina Weibo     

Bernard J. Jansen 《Information processing & management》2018,54(2):159-174

With the noted popularity of social networking sites, people increasingly rely on these social networks to address their information needs. Although social question and answering is potentially an important venue seeking information online, it, unfortunately, suffers from a problem of low response rate, with the majority of questions receiving no response. To understand why the response rate of social question and answering is low and hopefully to increase it in the future, this research analyzes extrinsic factors that may influence the response probability of questions posted on Sina Weibo. We propose 17 influential factors from 2 different perspectives: the content of the question, and the characteristics of the questioner. We also train a prediction model to forecast a question's likelihood of being responded based on the proposed features We test our predictive model on more than 60,000 real-world questions posted on Weibo, which generate more than 600,000 responses. Findings show that a Weibo's question answerability is primarily contingent on the questioner versus the question. Our findings indicate that using appreciation emojis can increase a question's response probability, whereas the use of hashtags negatively influences the chances of receiving answers. Our contribution is in providing insights for the design and development of future social question and answering tools, as well as for enhancing social network users’ collaboration in supporting social information seeking activities.  相似文献   

Ancient Mural Classification Method Based on Improved AlexNet Network     

Jianfang Cao  Hongyan Cui  Qi Zhang  Zibang Zhang 《文物保护研究》2020,65(7):411-423

ABSTRACT

As an important part of art and culture, ancient murals depict a variety of different artistic images, and these individual images have important research value. For research purposes, it is often important to first determine the type of objects represented in a painting. However, the mural painting environment makes datasets difficult to collect, and long-term exposure leads to underlying features that are not distinct, which makes this task challenging. This study proposes a convolutional neural network model based on the classic AlexNet network model and combines it with feature fusion to automatically classify ancient mural images. Due to the lack of large-scale mural datasets, the model first expands the dataset by applying image enhancement algorithms such as scaling, brightness conversion, noise addition, and flipping; then, it extracts the underlying features (such as fresco edges) shared by the first stage of a dual channel structure. Subsequently, a second-stage deep abstraction is conducted on the features extracted by the first stage using a two-channel network, each of which has a different structure. The obtained characteristics from both channels are merged, and a loss function is constructed to obtain the classification result. This approach improves the model's robustness and feature expression ability. The model achieves an accuracy of 84.24%, a recall rate of 84.15%, and an F1-measure of 84.13% when applied to a constructed mural image dataset. Compared with the AlexNet model and other improved convolutional neural network models, the proposed model improves each evaluation index by approximately 5%, verifying the rationality and effectiveness of the model for automatic mural image classification. The mural classification model proposed in this paper comprehensively considers the influences of network width and depth and can extract rich details from mural images from multiple local channels. An effective classification method could help researchers manage and protect mural images in an orderly fashion and quickly and effectively search for target images in a digital mural library based on a specified image category, aiding mural condition monitoring and restoration efforts as well as archaeological and art historical research.  相似文献   

基于二模复杂网络的隐性知识发现方法研究——以潜在药物靶点挖掘为例     

李东巧  陈芳  韩涛  杨艳萍  王学昭  王燕鹏  Cynthia Liu  Yingzhu Li 《图书情报工作》2020,64(21):120-129

[目的/意义] 通过构建二模复杂网络模型，揭示隐藏在海量文献中的隐性知识。[方法/过程] 通过NetworkX复杂网络工具包，依据任意两个节点的共现关系构建二模复杂网络模型；对网络模型中节点的共现关系进行加权，计算网络的拓扑信息并进行AP聚类，提取节点间的直接关系；采用AUC方法对AA、JC、加权改进的wAA和wJC等4种链路预测算法进行评价，遴选出最合适的预测算法，并对复杂网络的隐性关系进行预测分析。[结果/结论] 以潜在药物靶点挖掘为例进行的实证研究结果表明，wAA链路预测算法为最优的链路预测算法；二模复杂网络模型、指标和方法体系在美国化学文摘社数据库中的药物靶点挖掘中具有一定的有效性。下一步计划在其他数据库中或其他研究领域中进行尝试，以进一步验证该模型的通用性和有效性。  相似文献   

人工智能时代情报学发展走向之辨——对本体论、感知论、方法论、服务论的再思考     

曹文振  赖纪瑶  王延飞 《情报学报》2020,39(5):557-564

人工智能相关技术的迅猛发展和逐步普及,使得情报学难以避免人工智能的融合趋势,无论这种融合是主动为之或是被动选择。然而学界对人工智能时代情报学学科的发展走向并未予以充分探讨,大部分研究均将焦点置于大数据与下一代互联网环境中进行论述。本研究将人工智能时代情报学学科走向解构为"本体论""感知论""方法论""服务论"四个论题,对每个论题借由理论面向与实践面向的二分法展开阐释,并从整体视角上提出应在人工智能洪流中找准情报学定位,不能忽视"人"在情报学中的价值以及重视跨学科融合、跨领域应用的发展趋势。  相似文献   

基于DE-SVM的船舶航迹预测模型     

刘娇  史国友  杨学钱  朱凯歌 《上海海事大学学报》2020,41(1):34-39

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   

基于神经网络的认知无线电合作频谱感知     

薛建伟  唐亮  卜智勇 《中国科学院大学学报》2020,37(3):379-386

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   

Social network data to alleviate cold-start in recommender system: A systematic review     

Lesly Alejandra Gonzalez Camacho  Solange Nice Alves-Souza 《Information processing & management》2018,54(4):529-544

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   

From shanzhai chic to Gangnam style: seven practices of cultural-economic mediation in China and Korea     

Tommy Tse  Victor Shin  Ling Tung Tsang 《Journal of Cultural Economy》2020,13(5):511-530

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   

The cumulative and residual fatigue response associated with soccer-specific activity performed on different playing surfaces     

Richard Michael Page  Ben Langley  Mitchell James Finlay  Matt Greig  Christopher Brogden 《Journal of sports sciences》2020,38(5):568-575

ABSTRACT

This study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rad·s^-1, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT.  相似文献   

从传递信息到营造体验:体育传播产品转型初探——基于传播游戏理论的考察     

付晓静  潘陈青  罗幽诗 《武汉体育学院学报》2020,54(2):11-17

传播游戏理论强调传播作为一种主观性游戏的存在，体育传播与此具有天然的契合点。该文在界定体育传播产品内涵、分析传播游戏理论观点的基础上，提出体育传播产品要从传递信息走向营造体验，要开发体育视频资源，利用VR技术增强赛事体验，借助机器人提升体育信息传播速度，采用数据可视化增强体育传播的趣味性与观赏性。  相似文献