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1.
Viewer gifting is an important business mode in live streaming industry, which closely relates to the income of the platforms and streamers. Previous studies on gifting prediction are often limited to cross-section data and consider the problem from the macro perspective of the whole live streaming. However, the multimodal information and the time accumulation effect of live streaming content on viewer gifting behavior are ignored. In this paper, we put forward a multimodal time-series method (MTM) for predicting real-time gifting. The core module of the method is the multimodal time-series analysis (MTA), which targets at effectively fusing multimodal information. Specifically, the proposed orthogonal projection (OP) model can promote cross-modal information interaction without introducing additional parameters. To achieve the interaction of multi-modal information at the same level, we also design a stackable joint representation layer, which makes each target modality's representation (visual, acoustic and textual modality) can benefit from all the other modalities. The residual connections are introduced as well to ensure the integration of low-level and high-level information. On our dataset, our model shows improved performance compared to other advanced models by at least 8% on F1. Meanwhile, the MTA is able to meet the real-time requirements of the live streaming setting, and has demonstrated its robustness and transferability in other tasks. Our research may offer some insights about how to efficiently fuse multimodal information, and contribute to the research on viewer gifting behavior prediction in the live streaming context.  相似文献   
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[目的/意义] 探究用户使用电子书意愿的影响因素,以有助于电子书产业走出缓慢的发展困境。[方法/过程] 以UTAUT2、使用满足理论为基础,从需求满足和外部情景因素两个层面构建影响因素模型,并将需求满足细化为内容需求、社交互动需求和休闲娱乐需求3个测量变量。采用问卷调查方法收集有效样本1 013份,使用AMOS21软件对模型进行验证。[结果/结论] 研究发现,需求满足、阅读习惯、价格价值、社会影响对使用意愿有正向影响作用,而激励措施对使用意愿有负向影响作用,努力期望对使用意愿的影响不显著,并依据研究结果提出促进电子书产业发展的建议。  相似文献   
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2019-2020年之交,我国暴发新型冠状病毒肺炎疫情(下文简称“新冠肺炎疫情”)。新冠肺炎疫情给国家各项事业的正常运行带来了严峻挑战,为打赢这场新冠肺炎疫情攻坚战,全国科技工作者纷纷从各自不同的领域为疫情防控贡献着自己的力量。体育事业作为国民事业的重要组成部分,如何积极应对新冠肺炎疫情给各项体育事业带来的冲击,深刻思考新冠肺炎疫情背景下各项体育事业的发展路径,是体育事业健康发展的必然诉求,也是体育科技工作的应然使命。学者当以天下苍生为己任,为国家出谋,为社会担当,为人民谋福。体育学术期刊亦须做好学术担当,肩负起应有的使命与责任,传播体育科技工作者针对此次疫情所开展的社会服务和智慧贡献,探究体育事业逆疫发展之道。为此,《体育学研究》编辑部从开展征稿活动的50余篇来稿中,聚焦群众体育、竞技体育和体育产业等领域,对钟秉枢、黄志剑、王凯、车冰清、宋昱等体育专家及青年学者的观点和思考进行集成,形成了《困境与应对:聚焦新型冠状病毒肺炎疫情对体育事业的影响》一文。以期为疫情的科学防控和推动体育事业健康发展提供理论和实践参考。  相似文献   
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运用文献资料法和逻辑分析法,以互动仪式链理论为视角,从文化资本互动与情感能量互动两方面对CBA球场暴力行为的发生机制进行研究。指出,赛前与赛中的互动仪式相互联系,赛前不良的互动仪式会将负向的情感能量带入比赛,使共享情感破裂,产生球场暴力现象。球员个体间情境互动会过渡到球队群际间,暴力行为会通过互动仪式链不断扩散到其他球队。比赛中双方都存在冲突性紧张,谁能抢占情感能量主导权谁就会在博弈中占据优势地位,处于压制的一方将转化为恐惧感。恐惧与冲突性紧张塑造了暴力情景,导致了球场暴力行为的发生。提出,应规范球员行为表现,防止球员暴力惯习的形成;加强球队球员间的沟通交流,修复断裂的互动仪式链条;注重裁判执裁能力建设,维持现场球队双方情感能量的平衡;营造有序的观赛环境,激发球迷潜在的道德情感。旨在为CBA健康有序发展提供建议与参考。  相似文献   
6.
Aspect-based sentiment analysis aims to determine sentiment polarities toward specific aspect terms within the same sentence or document. Most recent studies adopted attention-based neural network models to implicitly connect aspect terms with context words. However, these studies were limited by insufficient interaction between aspect terms and opinion words, leading to poor performance on robustness test sets. In addition, we have found that robustness test sets create new sentences that interfere with the original information of a sentence, which often makes the text too long and leads to the problem of long-distance dependence. Simultaneously, these new sentences produce more non-target aspect terms, misleading the model because of the lack of relevant knowledge guidance. This study proposes a knowledge guided multi-granularity graph convolutional neural network (KMGCN) to solve these problems. The multi-granularity attention mechanism is designed to enhance the interaction between aspect terms and opinion words. To address the long-distance dependence, KMGCN uses a graph convolutional network that relies on a semantic map based on fine-tuning pre-trained models. In particular, KMGCN uses a mask mechanism guided by conceptual knowledge to encounter more aspect terms (including target and non-target aspect terms). Experiments are conducted on 12 SemEval-2014 variant benchmarking datasets, and the results demonstrated the effectiveness of the proposed framework.  相似文献   
7.
The domain about what it means to give responsible and human centric recommendations in the context of Artificial Intelligence (AI)-based insurance has not yet been fully explored. In this article, we therefore, first provide an in-depth analysis and perform a systematic literature review on (i) the specifications and requirements for such systems from a regulation point of view, (ii) instructions on which data they can rely upon, (iii) which recommender techniques can be used for developing such an advisor, (iv) off-the-shelf components for the trustworthy, responsible, and ethical behavior of this AI-empowered tool. Then, we present a novel approach, based on AI, to suggest insurance coverage for users and families, as well as instructions on how to design such a system. The solution, as proposed in our paper, will be transparent, trustworthy, and responsible to the final users and thus, hopefully, better accepted by customers. After describing a possible system design and architecture, we critically discuss the challenges and opportunities for the deployment of such systems in insurance companies.  相似文献   
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Recently, models that based on Transformer (Vaswani et al., 2017) have yielded superior results in many sequence modeling tasks. The ability of Transformer to capture long-range dependencies and interactions makes it possible to apply it in the field of portfolio management (PM). However, the built-in quadratic complexity of the Transformer prevents its direct application to the PM task. To solve this problem, in this paper, we propose a deep reinforcement learning-based PM framework called LSRE-CAAN, with two important components: a long sequence representations extractor and a cross-asset attention network. Direct Policy Gradient is used to solve the sequential decision problem in the PM process. We conduct numerical experiments in three aspects using four different cryptocurrency datasets, and the empirical results show that our framework is more effective than both traditional and state-of-the-art (SOTA) online portfolio strategies, achieving a 6x return on the best dataset. In terms of risk metrics, our framework has an average volatility risk of 0.46 and an average maximum drawdown risk of 0.27 across the four datasets, both of which are lower than the vast majority of SOTA strategies. In addition, while the vast majority of SOTA strategies maintain a poor turnover rate of approximately greater than 50% on average, our framework enjoys a relatively low turnover rate on all datasets, efficiency analysis illustrates that our framework no longer has the quadratic dependency limitation.  相似文献   
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俄罗斯国家奥委会遭国际奥委会(IOC)暂停成员资格,导致很多无辜运动员无法参加平昌冬奥会,国际体育仲裁院(CAS)平昌冬奥会特别仲裁机构处理的数起案件均涉及俄罗斯运动员的参赛资格问题。俄罗斯运动员在仲裁程序中败诉的主要原因是《奥林匹克宪章》规定:奥运会是IOC的专属财产、任何人不拥有参加奥运会的所谓权利、IOC可以拒绝任何人参赛而无须出具理由。IOC运用对奥运会的专属权利,无正当合理理由拒绝符合参赛条件的俄罗斯清白运动员参赛,有构成垄断的嫌疑。符合参赛选拔条件、且不存在禁止性限制因素(如兴奋剂禁赛处罚在身)的清白运动员参加奥运会,是他们的权利,而不是IOC赋予他们的特权。切实保护运动员参赛权利是各国法院和国际体育仲裁院在处理体育参赛资格案件中的一贯立场,平昌冬奥会仲裁庭的实践过于保守。奥林匹克运动体育善治的改革,要求必须对《奥林匹克宪章》进行修改,最大限度地保护运动员的参赛权利,实现《运动员权利与义务宣言》的宗旨。  相似文献   
10.
目的:分析舞龙运动对女大学生血常规及内皮祖细胞含量的影响。方法:选取2017级舞龙队女大学生10人为训练组,2017级普通女大学生10人作为对照组。舞龙队女大学生备战比赛进行连续4周,每周3次,每次90min的赛前集训,普通女大学生除日常活动外,没有额外进行任何其他运动队的集训。集训结束后,在受试者都处于空腹状态下对两组受试者进行静脉采血并进行血常规、早期内皮祖细胞和晚期内皮祖细胞的检测。所得数据进行统计学分析。结果:参加舞龙集训的女大学生的血常规指标与普通女大学生的血常规指标无显著差异,早期EPCs和晚期EPCs无显著性差异,但在数值上显示出不同的趋势。结论:参加舞龙集训的女大学生身体处于健康状态。参加舞龙集训有可能增强运动员血管的自我修复能力。  相似文献   
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