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1.
This article examines peer influences from network relationships within a social network game (i.e., embeddedness) and across such games (i.e., multiplexity). Drawing on social influence theory, we develop a bivariate Poisson model of users’ repeated visits and latent attrition that accommodates peer interaction after controlling for homophily. We estimate the model using data from two social network games with considerable overlap among network members. We find that friends who are only multiplex across games exert greater peer influence on users’ game visits than members who are embedded within a single game. We also determined that ignoring network multiplexity across games may lead firms to mistarget users due to biased peer influences of embedded friends. This result provides an unresearched explanation—strength of peer influence—for the mixed findings in previous literature on network embeddedness. We utilized our results to conduct several scenario analyses to demonstrate how firms can effectively manage users’ engagement and target users in multiple social network games.  相似文献   
2.
碳达峰和碳中和的提出对城市群发展提出新的要求,城市群高速发展与环境问题间的矛盾日益加剧,绿色低碳发展路径亟待研究.以京津冀城市群为研究对象,在梳理城市群发展影响因素的基础上,分析城市群循环系统构成中要素间的关联关系,并通过量化模型,搭建基于系统动力学的城市群绿色低碳发展系统;重点从经济、能源、环境和城市聚合4个角度构建仿真系统,建立要素间量化函数,设定基本场景,以2010—2019年数据为基础,对系统进行仿真运行.算例结果表明,构建的仿真系统通过了检验,拟合程度较好;通过设计不同场景,验证相关参数变化时对系统运行的影响程度,发现综合场景对未来系统运行效益最佳,兼顾了经济发展与碳减排问题,能够促进城市向群绿色低碳发展.  相似文献   
3.
苏南乡村地区一直是中国乡村建设的先行区域,特殊的纵横交错的水网结构构成了一个错综复杂的系统,呈现出其他地区不具有的复杂性和生态特殊性。随着城镇的扩张,乡村的发展建设使其水网空间的平衡发展面临极大的挑战。传统单一静态的规划方法逐渐显示出无法适应经济、社会等发展要求的缺陷。苏南乡村地区以水为核心,从水生态系统服务供需关系的视角下探究水网乡村的适应性规划策略更加适应当前的乡村现状和需求。以传统水网乡村空间形态转译为基础,建立水生态系统供需服务评估体系,在评估水生态系统服务供需能力的基础上,分析供需分异模式及供需矛盾。从构建乡村水域空间生态格局、乡村水域空间功能分区规划,以及乡村水域空间多情景预判3个方面,提出苏南水网乡村的适应性规划策略,并为水网乡村的生态实践提出新思路。  相似文献   
4.
许瑾  刘炫均  冯冠钦 《科技和产业》2021,21(10):302-308
随着电力变压器朝着大容量、高电压、高负荷的方向发展,其结构也越发复杂,故障逐渐增加.当前广泛使用的改良三比值法在对电力变压器进行故障诊断的过程中,容易出现准确率低和漏判率高等问题.鉴于此,提出一种NBC模型,该模型将朴素贝叶斯网络和改良三比值法的优势结合,在对电力变压器当前状态数据和历史样本数据充分学习的基础上,利用朴素贝叶斯分类器对当前电力变压器故障的编码组合进行故障预测分类,将预测所得到的诊断结果进行排序整理输出,实现了对电力变压器各类故障的有效分类.仿真结果表明,该NBC模型能较好地适应电力变压器各类故障的诊断,故障综合诊断正确率为95%,相较于改良三比值法,诊断准确率提升了50%,具有较强的工程实用性.  相似文献   
5.
Marine‐protected areas (MPAs) are an effective means of improving habitat quality and biodiversity in the world’s oceans. While the advantages of MPAs as a mechanism for conservation and biodiversity are well established, the potential improvements to fishery performance resulting from a network of MPAs are still being established. Countries around the world have committed to establishing networks of MPAs within their waters by 2020, in response to the United Nations Convention on Biological Diversity. This, coupled with the increasing global demand for seafood and heavy reliance on fishery resources as a source of economic development for many coastal communities, means that an understanding of how these networks can be expected to impact fishery performance is extremely important. We use a difference‐in‐difference modelling approach to isolate the change in the fishery performance associated with the south‐east marine reserve network in Australia. We find no evidence that the economic performance of adjacent fisheries was negatively impacted by the network. This lack of impact is likely due to a network design explicitly intended to avoid effort displacement in key fisheries, along with fishery management changes intended to remove excess fishing capacity.  相似文献   
6.
丁可心  李雨婷 《物流科技》2021,(2):59-61,68
近些年来,我国众多城市都出现了"垃圾围城"的现象,垃圾回收处理也成为了社会广泛关注的热点,但是众多学者对相关理论的研究成果并没有被系统性的总结。文章将在绿色物流视角下,对生活垃圾回收处理的相关研究进行全面梳理,从居民垃圾分类意识、垃圾回收处理服务网络构建、垃圾回收站点及中转站的选址等三个方面进行综述,最后进行述评和研究展望。  相似文献   
7.
Circular business models (CBMs) have huge potential to deliver economic, social, and environmental benefits, but CBMs have yet to be implemented widely in industrial settings. One reason is that they are often presented as one-size-fits-all solutions, but this is misplaced because product-specific criteria and company capabilities determine the correct choice and implementation of CBMs. Therefore, the purpose of this paper is to investigate how CBM selection and capability development facilitates the implementation of CBMs. For this purpose, we have adopted a qualitative research approach and undertaken 25 explorative interviews in three large Swedish manufacturing companies. In this paper, a CBM implementation framework consisting of two parts has been developed. The first part addresses the choice of the appropriate CBM based on tactical configurations. The second part provides a capability development path by explicating underlying routines that need to be progressively developed in order to move smoothly to more advanced CBMs.  相似文献   
8.
随着当前社会与经济的发展,对于石油等能源物质的需求量不断增加,石油在物流运输过程中所产生的成本也在不断提升。为降低我国石油物流运输工作过程中的成本,需要对当前石油物流的整体发展进行研究,并且基于此构建中国石油物流网络系统,从而使石油物流网络的整体运转效率得到提升并且降低成本。  相似文献   
9.
Online-to-offline (O2O) has become a rapidly growing e-commerce model worldwide, but the factors influencing consumers' purchase decision-making have not been examined well. After exploring the working mechanism of the O2O model, we extract eleven indexes of consumers' overall evaluation in the O2O model with Crawlzilla and R techniques. Social network analysis (SNA) is adopted to build social networks reflecting consumers' overall evaluation in the O2O model. Based on the modified social network and the extracted subgraph, this study (N = 768) reveals consumers' overall evaluation behavior patterns in the O2O model by calculating network density, central potential, edge betweenness. The results show that shoppers overall evaluate the eleven indexes, especially perceived product quality, online product price, promotion intensity, business reputation, and product brand, which reflects the significant associations between the indexes. Among all the eleven evaluation indexes, perceived product quality, online product price, and business reputation dominate consumers’ decision-making behavior. When making purchase decisions, consumers not only overall consider online product price, perceived product quality, and business reputation but also balance perceived product quality, business reputation, and promotion intensity. Finally, we make some suggestions on marketing strategy for e-commerce companies.  相似文献   
10.
李培哲 《技术经济》2020,39(6):34-43,53
战略性新兴产业是近几年新出现的研究热点,对其科研合作网络的研究,有助于探究该领域的科研合作现状与发展趋势。基于社会网络分析方法,以中国知网(CNKI)作为数据来源,构建了战略性新兴产业领域作者合作网络、关键词共现网络、作者-关键词耦合网络及机构合作网络,对合作网络的结构及特性等进行了分析。结果表明:战略性新兴产业领域论文合著率基本呈上升趋势,但该领域整体合作仍较为松散,存在较多的小团体;合作网络具有小世界和无标度特性,具有较大影响力的节点作为合作网络的中心,影响着网络内的学术交流和科研工作的开展。  相似文献   
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