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61.
Virtual interlining, which covers the actively marketed or ‘non-hidden’ segment of all potential self-connecting flight itineraries, is often assumed to be a money-saving travel strategy. In this paper we assess the price difference between virtual interlined and ‘traditional’ flight itineraries within the intra-European airport network. We query Kiwi.com's recently developed Tequila platform, one of the few specialised online travel agencies (OTAs) offering both ‘traditional’ and virtual interlined flight itineraries, to obtain information on all available flights in the first week of August, October and December 2019. Using a series of sign tests, we investigate whether a statistically significant fare difference exists between the cheapest available (direct and/or indirect) ‘traditional’ and virtual interlined flight itineraries. Our results indicate a statistically significant fare difference between the cheapest indirect ‘traditional’ and the virtual interlined flight itineraries in favour of the latter. However, with regard to direct traditional flight itineraries the results are mixed. We explore the size and the scope of these patterns in more detail, and outline possible avenues for further research. 相似文献
62.
David Ahlstrom Jean-Luc Arregle Michael A. Hitt Gongming Qian Xufei Ma Dries Faems 《Journal of Management Studies》2020,57(3):411-437
A New Normal environment for business has emerged in the years after the 2008 financial crisis based on numerous changes in the world's economic, technological, demographic, and sociopolitical factors. This combination of changes has created a New Normal environment for firms with major implications for managers, strategists, and entrepreneurs alike. It has resulted in an environment with new challenges and opportunities that are considerably different from what firms had to contend with in the years previous. In this paper, we present the main changes that characterize the current New Normal business environment and highlight some key implications for strategy and management. Then, we present the nine articles in this special issue dealing with different dimensions of this new environment for firms. Subsequently, we outline some future research questions that could help to advance our knowledge of the New Normal environment and its implications for firms and management theories. In examining the New Normal, it is important to be reminded that the world is indeed round and even small actions on one side of the globe can have a major impact on organizations on the other side of the globe. 相似文献
63.
《Socio》2020
Electricity generation capacity expansion is driven by both economic and socio-political realities. Policy makers determine public infrastructural decisions, such as climate and renewable targets, and transmission infrastructure, and the optimal generation capacity expansion follows. Policy makers therefore require planning models that can determine the optimal generation capacity mix in the long run under various scenarios, including policy choices. This work presents a planning model based on linearised alternating current optimal power flow which determines optimal generation capacity expansion and operation, in a least-cost manner, given global and local technical constraints, as well as policy decisions. We apply the model to a test case of the island of Ireland, which has two weakly interconnected systems, high renewable generation targets and low storage and interconnection. We determine the optimal generation expansion and operation out to 2030 considering the effects of increased multi-area interconnection, existing fossil fuel generation phase-out and increased renewable generation targets and carbon prices. Our results find that costs and emissions are driven primarily by the decommissioning of old inefficient generation units. High renewable targets, on the other hand, render increased carbon prices relatively ineffective in reducing system emissions. Furthermore, high renewable generation targets crowd out low-carbon power generation options such as carbon capture and storage (CCS). The strategic north-south interconnection has little effect on renewable energy source installations required to achieve renewable power generation targets but does impact on security of supply and the congestion level across the island. 相似文献
64.
运用中国家庭金融调查(CHFS)数据,研究社会互动与家庭金融资产配置之间的关系。研究发现,适当增强社会互动会促进家庭更多地参与风险金融市场,增加投资风险资产的比例,提高金融资产的分散化程度,优化资产的配置效率。但当社会互动达到一定程度后,过度的社会互动则会抑制家庭参与风险市场,减少风险资产的投资比重,降低金融资产的分散化程度以及资产配置的有效性。因此,家庭需要建立适度而高质量的社会互动,这有助于家庭获得更多的外部资源,缓解信息不对称,降低交易成本,从而优化家庭金融资产配置。 相似文献
65.
针对冷链物流时效性强这一特性,应用软时间窗反映客户满意度,并结合T.T.T理论换算货损成本。在考虑满足客户时间窗的条件下,寻找配送中心建设及操作成本、车辆成本、惩罚成本及货损成本所构成的总成本最小时的最优配送方案,建立冷链物流配送选址及路径优化的双层规划模型,并将改进的遗传算法运用到该模型中,借助Matlab软件对具体实例进行求解,得到最优结果,为冷链物流网络多目标优化问题提供理论依据。 相似文献
66.
资本市场认为互联网公司市值的驱动因素应包括盈利因子、运营因子、流量因子和协同因子。将协同效应指标考虑到公司估值体系中,意图构造互联网公司优化估值模型。使用美股上市的互联网企业数据建立了评价指标体系,通过因子分析实现了二级指标降维,通过实证分析确认了四个因子与公司市值的相关关系,最后构建了基于人工神经网络BP算法的互联网公司估值模型,通过预测数据的检验发现模型的准确度较高。随着2018年互联网公司美股上市潮的持续,该模型能有效为资本市场估值提供参考。 相似文献
67.
This paper investigates the systemic risk spillovers and connectedness in the sectoral tail risk network of Chinese stock market, and explores the transmission mechanism of systemic risk spillovers by block models. Based on conditional value at risk (CoVaR) and single index model (SIM) quantile regression technique, we analyse the tail risk connectedness and find that during market crashes, stock market exposes to more systemic risk and more connectedness. Further, the orthogonal pulse function shows that Herfindahl-Hirschman Index (HHI) of edges has a significant positive effect on systemic risk, but the impact shows a certain lagging feature. Besides, the directional connectedness of sectors shows that systemic risk receivers and transmitters vary across time, and we adopt PageRank index to identify systemically important sector released by utilities and financial sectors. Finally, by block model we find that the tail risk network of Chinese sectors can be divided into four different spillover function blocks. The role of blocks and the spatial spillover transmission path between risk blocks are time-varying. Our results provide useful and positive implications for market participants and policy makers dealing with investment diversification and tracing the paths of risk shock transmission. 相似文献
68.
随着我国科学技术的不断发展,计算机被广泛应用于各行各业的发展建设以及人们日常生活和学习中,在给人们带来较大便利的同时,也存在安全隐患。网络安全问题威胁到了计算机信息的保密性,给计算机的可持续发展带来了安全隐患,若用户的信息被泄露会给用户带来巨大的财产损失及心理伤害。因此,出现了数据加密技术,其为计算机网络安全提供了很好的保障。基于此,论文对数据加密技术在提高网络安全性中的应用方面作了简要阐述。 相似文献
69.
ABSTRACTR&D network structures have crucial impacts on firm's innovation performance. However, most previous studies have been based on the whole or ego network perspective, few studies have investigated the influence of community structure that a firm is engaged in on its innovation performance, and it is still unclear how a firm's relation to network community affect its innovation performance. This research aims to address this gap by focusing on the dynamics of firm's network community associations, empirically investigate the relationship between dynamics of firm's network community associations and its innovation performance. Based on the unbalanced panel data of smartphone R&D network during year 2004–2017, the results demonstrate that change in community member associations and movement across communities both have inverted-U-shaped effects on firm's innovation performance. Moreover, innovation openness depth has moderating effects on the relationships between dynamics of firm's network community associations and its innovation performance. 相似文献
70.
ABSTRACT Firm innovation is embedded in a collaboration network among researchers and a knowledge network composed of knowledge elements; the two networks are decoupled. Guided by social network theory, this study puts forward the definition and the classification of firm dual network structure, probes into the influence of dual network structure on firm performance, and explores the alignment between innovation strategy and firm dual network structure. We conduct an empirical study of 183 listed companies in China from 2004 to 2018. It is found that the four types of dual network structure all have positive impacts on firm performance, and the impact of a collaboration network is slightly higher than that of a knowledge network. Besides, innovation strategy plays a positive moderating role in the relationship between dual network structure and firm performance. Our findings provide new ideas for firms to identify and optimise knowledge and collaboration network structures and match them with innovation strategy to improve performance. 相似文献