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991.
ABSTRACT Research on media substitution theory has examined substitutional and/or complementary relationships between new and existing media. This study focuses on the growth of mobile platforms and investigates the relationship between mobile devices and personal computers. Using Nielsen’s panel data that provide electronically recorded media usage (N = 2,396), this study analyzes yearly changes in time allocation to mobile devices and PCs at total and content-specific usage levels during mobile 4G transition. Results suggest a complementarity dynamic between mobile devices and PCs; however, the patterns were more nuanced in light of the role of individual and structural factors when determining media choice. 相似文献
992.
Yang Liu Binghong Gao Jiru Li Zuchang Ma Yining Sun 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(2):168-179
AbstractThe aim of this study was to investigate whether changes on foot-stretcher height were associated with characteristics of better rowing performance. Ten male rowers performed a 200 m rowing trial at their racing rate at each of three foot-stretcher heights. A single scull was equipped with an accelerometer to collect boat acceleration, an impeller with embedded magnets to collect boat speed, specially designed gate sensors to collect gate force and angle, and a compact string potentiometer to collect leg drive length. All sensor signals were sampled at 50 Hz. A one-way repeated measures ANOVA showed that raising foot-stretcher position had a significant reduction on total gate angle and leg drive length. However, a raised foot-stretcher position had a deeper negative peak of boat acceleration at the catch, a lower boat fluctuation, a faster leg drive speed, a larger gate force for the port and starboard side separately. This could be attributed to the optimisation of the magnitude and direction of the foot force with a raised foot-stretcher position. Although there was a significant negative influence of a raised foot-stretcher position on two kinematic variables, biomechanical evidence suggested that a raised foot-stretcher position could contribute to the improvement of rowing performance. 相似文献
993.
后脱钩时代,全国单项体育协会坚持依法自治不仅是"依法治体"的基本要求,而且也是脱钩改革有效落实的基本保证。针对全国单项体育协会存在的自治权性质界定不统一、非营利性属性规定不明确、体育行政权力异化、内部法人治理机制不健全的法治困境,从实体和程序上两方面来保障实现全国单项体育协会自治的法治化,以便真正实现单项协会的实体化,具体提出了单项协会自治主体性质的明确、相关法律规定的完善、非营利性标准的明晰界定等措施。 相似文献
994.
[目的/意义]颠覆性技术能变革传统生产模式和消费结构,使产业格局巨变。识别潜在颠覆性技术有助于抢占科技制高点,在科技竞争中取得先发优势。[方法/过程]通过主题检索和引文回溯搜集文献,梳理颠覆性技术现阶段的主要识别方法。[结果/结论]发现方法的选择与研究人员学科背景密切相关,根据研究人员的主要研究领域,将其划分为图书情报、工程管理、经济研究和Christansen流派4类识别方法。在此基础上对识别方法进行7个维度的比较,指出现有方法存在3个问题:过度依赖专家评价、识别标准针对性不足和超前识别效果不佳,其中识别标准针对性不足是核心问题。鉴于此,在后续研究中应当从多种角度不断探究和完善技术颠覆潜力的评价方法。 相似文献
995.
996.
唐诗知识图谱的构建及其智能知识服务设计 总被引:2,自引:0,他引:2
[目的/意义]立足于当前大数据环境下的唐诗知识服务需求,以大规模唐诗数据为基础构建唐诗知识图谱并提供智能知识服务,推动人工智能环境下唐诗知识管理和知识服务方式的创新。[方法/过程]本文在对领域知识服务需求调研的基础上,设计领域知识服务驱动的唐诗本体模型,然后利用从Web上爬取的多源异构数据,采用知识抽取、知识融合、知识推理等技术自动构建唐诗知识图谱,统一表示和组织唐诗领域数据,实现对大规模唐诗数据的语义化处理。[结果/结论]本文设计基于唐诗知识图谱的智能知识服务平台KnowPoetry,提供唐诗领域的知识探索、时空轨迹、语义查询等智能化知识服务,推动人工智能环境下唐诗数字人文研究方法的创新转型。 相似文献
997.
[目的/意义]采用被引次数衡量学术论文影响力存在诸多弊端。本文认为学术论文影响力包括其传播的深度、速度和广度3个方面,熵可用于衡量学术论文影响力传播的广度。[方法/过程]选择1901-2017年生物医学领域的诺贝尔奖论文作为最具影响力的论文纳入实验组,并根据1:1配对原则设立对照组,比较两组论文发表后5年内其施引文献所属学科数量、熵以及熵与被引次数的相关性。[结果/结论]实验组中65%以上的论文施引文献学科数量高于对照组;实验组熵的均值介于0.552-0.772,对照组介于0.251-0.481,有显著性差异(P<0.05);两组论文的被引次数与熵的相关性较弱,均小于0.3。结果表明:①70%以上的高影响力论文在发表早期能够影响较多的学科;②采用熵对论文影响力广度进行识别具有可行性。 相似文献
998.
高逢亮 《佳木斯教育学院学报》2014,(6):194-195
高级阶段埃及学生的写作偏误具有高度的一致性特点,大致可从微观方面及宏观方面两个角度来分析,其中微观方面指的是句子内部及句际的写作偏误,宏观方面则是指文章整体所体现出来的特点。对汉语学习者写作偏误的分析,必定能为我们进一步改进对外汉语写作教学提供指导意见。 相似文献
999.
María-Ángeles Chaparro-Domínguez Juan-Carlos Suárez-Villegas Ruth Rodríguez-Martínez 《Journalism Practice》2020,14(7):812-829
ABSTRACT This paper analyses to whom Spanish journalists feel responsible. To achieve this objective, we sent out a survey to Spanish journalists to ascertain their opinion on this question. The journalists’ point of view was then compared with that of the general public though six focus groups consisting of Spanish citizens from six cities in Spain (Barcelona, Castellón, Madrid, Sevilla, Mondragón and Santiago de Compostela). Lastly, five in-depth interviews were conducted with journalism experts (e.g., directors of professional journalist associations). The main results show that the journalists feel particularly responsible to their conscience, the journalism code of ethics and their sources. The citizens, in contrast, believe that journalists should be responsible to the audience. We contextualised the Spanish finding in the European context by comparing our results with those derived from a study among European journalists. 相似文献
1000.
Human collaborative relationship inference is a meaningful task for online social networks and is called link prediction in network science. Real-world networks contain multiple types of interacting components and can be modeled naturally as heterogeneous information networks (HINs). The current link prediction algorithms in HINs fail to effectively extract training samples from snapshots of HINs; moreover, they underutilise the differences between nodes and between meta-paths. Therefore, we propose a meta-circuit machine (MCM) that can learn and fuse node and meta-path features efficiently, and we use these features to inference the collaborative relationships in question-and-answer and bibliographic networks. We first utilise meta-circuit random walks to obtain training samples in which the basic idea is to perform biased meta-path random walks on the input and target network successively and then connect them. Then, a meta-circuit recurrent neural network (mcRNN) is designed for link prediction, which represents each node and meta-path by a dense vector and leverages an RNN to fuse the features of node sequences. Experiments on two real-world networks demonstrate the effectiveness of our framework. This study promotes the investigation of potential evolutionary mechanisms for collaborative relationships and offers practical guidance for designing more effective recommendation systems for online social networks. 相似文献