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51.
This editorial article introduces the papers presented at the ITS Seoul 2018 and seven papers selected for the special issue of ITS Seoul 2018. Specifically, this article provides the results of keyword networks, research agendas and coauthor networks of ITS Seoul 2018. A summary of the seven papers accepted for the special issue of ITS Seoul 2018 is also included. Finally, this article concludes by introducing another paper that empirically explores the value of special issues by analyzing the characteristics of special issues of Telecommunications Policy.  相似文献   
52.
The collapse of real estate prices has historically jeopardized banking stability and triggered systemic banking crises. This paper studies risk contagion in a banking system in real estate price shock by adopting complex network theory. Modelling the real estate-related asset as a common exposure of banks to the real estate market, we propose a model that incorporates two main risk contagion channels, i.e., the financial network and asset fire sales, and reveal how the real estate price shock is transmitted and propagated across banks. We demonstrate that banking stability is highly sensitive to the real estate price shock. Moreover, due to the particularly low liquidity of the real estate market, the asset fire-sales of real estate assets overwhelms the financial network, playing the dominant role in risk contagion. Our model can be adopted by regulators to conduct stress testing and to forge effective risk management strategies.  相似文献   
53.
Regional paved roads are low volume roads with a prevalence of heavy traffic. In the world, these roads concern about 80% of the total road network; however, the traffic that affects these roads is about 20%. Since regional roads are characterized by weak demand, budget for their management/maintenance is very low. This produces considerable difficulties in the choice of strategies for maintenance planning and scheduling. For this reason, the recurring topics of research in this field deal with typical roads issues and aim to develop low cost tools and methods. The study proposes a decision support system to evaluate regional paved roads operating condition in relation to the hydrogeological situation. In particular, the system allows to evaluate in a quick and easy manner, the operating conditions of the road, through low-cost tools (i.e. using low economic resources). This is very useful in the case of LVRs because administrations for these roads have a limited budget. The procedure is developed on a regional paved roads network based on more than 80 roads located in Southern Italy. Data is collected by direct surveys in the field and is integrated with cartography and information available in road agency records. From data analysis, obtained using two different techniques, an easy and quick use procedure is made. In particular, Model 1 is built through multivariate analysis and Model 2 using the artificial neural network (ANN) technique. The results show the validity of the two models in Regional paved roads operating conditions estimation in relation to hydrogeological situations of sites. Both models show good reliability. In particular, the first model (Model 1) is characterized by a high level of significance (p < 0.01) and by a coefficient of determination equal to 0.82. Comparative tests between the second model (Model 2) on which standard tests cannot be performed for obvious reasons, and the first model (Model 1). The results show that the ANN model (model 2), characterized by lower residual, simulates more accurately than the second (Model 1).  相似文献   
54.
55.
The advanced development of broadband access is an inevitable step toward supportive daily lives and sustainable economic growth. However, the decisive outcome of the development relies heavily on the demand side. Consumer choice among advanced Internet broadband technologies will determine the achievement of the development. This study aims to illustrate that consumer decisions on choices of advanced Internet access are influenced by the emergence of the Internet of Things (IoT) applications. A bivariate probit model is applied to examine the effects of IoT, consumer's individual characteristics, and their current use of networks on their decision pertaining to the choice of advanced Internet access. Using Thailand as a case study, the result indicates that the emergence of IoT applications accelerates the adoption of both advanced mobile broadband (5G) and advanced fixed broadband (FTTH). This finding may help policy makers to optimize the future direction of the Internet infrastructure development in Thailand, and also countries in a similar stage.  相似文献   
56.
This paper investigates the high-speed broadband situation in the EU and its prospects. It uses a deployment model to estimate the investment required to meet the Digital Agenda for Europe (DAE) broadband targets set by the European Commission in its Europe 2020 strategy at different stages: as of 2016, after expected operators’ deployment, after public subsidies and leveraged investment, and as expected in 2020. The model uses data at the NUTS3 level, which is the most granular level that has data available on the status of broadband deployment, to arrive at a coherent and comparable framework. From the different perspectives on the investment to meet DAE targets, the paper concludes on the need for an appropriate combination of incumbent and alternative operators investments, public subsidies and leveraged investments, and new investments, both public and private and non-existing as of 2016, examining their feasibility and the impact of different regulatory, technical, and policy strategies.  相似文献   
57.
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   
58.
A large body of research shows that the migration of managers from one professional service firm to another weakens the old employer’s relationship with its clients, because migrating managers remove their relationship-specific knowledge and expertise – i.e., human and social capital – from their old employers, redeploying it to their new employers. This study extends this research by introducing a bi-directional perspective of social capital in which both firms and managers may exploit these relationship-specific resources. We use theory on social capital to build arguments about how one form of manager mobility, manager migration between two service providers in a single market, can both lead and lag the movement of client ties between those providers, and signaling theory to hypothesize the conditions under which this is likely to occur. Analyses using longitudinal data on New York City advertising agencies generally support our arguments. Our findings contribute to theory and research on manager migration, social capital, and signaling, and raise new questions for how the portability of relationship-specific social capital shapes markets.  相似文献   
59.
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   
60.
周梓渝  蒋惠园 《物流技术》2020,(2):65-70,145
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   
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