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21.
Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.  相似文献   
22.
Under increasing regulatory pressure to disclose environmental impacts, corporate environmental information disclosure (EID) is becoming more prevalent. However, the motives for EID and disclosure approaches (i.e., symbolic or substantive) remain controversial. Using a sample of data for 742 listed manufacturing firms in China across 3 years, we provide evidence to show that the level of EID is significantly positively associated with a firm's advertising intensity and that firms in moderately competitive industries have a higher propensity for adopting an EID‐based differentiated strategy than firms in stronger or weaker competitive industries. We also find that firms that are more sensitive to environmental issues strategically understate their environmental impact when directly facing consumers. Our results suggest that the implementation of corporate EID is strategic and that firms have strong market motives, even under regulatory pressure to demonstrate legitimacy. We discuss this study's contributions to research on EID theory and implications for strategic EID management.  相似文献   
23.
监测对于国家公园的科学保护管理与规划具有重要意义。中国正处于国家公园体制建设初期,有必要深入研究如何建立国家公园监测体系。以近20年来发展迅速的美国、加拿大和英国的国家公园监测体系为研究对象,基于文献调查和比较分析,从监测内容框架与指标、数据管理与转化、组织和保障3个方面梳理在各自资源与管理背景下国家公园监测体系的基本特点,并提取出面向规划管理的国家公园监测体系建设的16个基本要点,为我国提供借鉴和启示。  相似文献   
24.
Many optimization-based portfolio rules fail to beat the simple 1/N rule out-of-sample because of parameter uncertainty. In this paper we suggest a grouping strategy in which we first form groups of equally weighted stocks and then optimize over the resulting groups only. This strategy aims at balancing the trade-off between the benefits from optimization and the losses from estimation risk. We rely on Monte-Carlo simulations to illustrate the performance of the strategy, and we derive the optimal group size for a simplified setup. Furthermore, we show that estimation risk also has an impact via the criterion by which the assets are sorted into groups (like the expected excess returns or betas), but does not negate the grouping approach. We relate our work to linear asset pricing models, and we conduct out of sample back-tests in order to confirm the validity of our grouping strategy empirically.  相似文献   
25.
I analyze the competition among different countries for ‘desirable’ and ‘undesirable’ potential immigrants, using both an immigration quota and a level of (imperfect) ‘scrutiny’ that would‐be immigrants face. Scrutiny imposes costs on immigrants and therefore makes it less attractive to immigrate. The number of applying undesirable immigrants increases in immigration quota and decreases in the level of scrutiny. In contrast, the number of desirable applicants can go in either direction as scrutiny increases and is independent of the immigration quota, because an increase in the immigration quota is completely crowded out by more applications by undesirable immigrants.  相似文献   
26.
We establish that the effect of intensified deposit market competition, measured by reduced switching costs, on the probability of bank failures depends critically on whether we focus on competition with established customer relationships or competition for the formation of such relationships. With inherited customer relationships, intensified competition due to lower switching costs destabilizes the banking market, whereas it stabilizes the market if we focus on competition for the formation of customer relationships. We characterize the factors important for evaluating the effects of intensified competition on stability in a market with unattached as well as locked-in depositors.  相似文献   
27.
This research investigates the effect of the separation between firm ownership and control on the cost of debt, with attention to the moderating role of state ownership and bank competition. We make use of a sample of 1744 Chinese A-share firms for the years 2011–2017. We find that separation between ownership and control is positively associated with the cost of debt. This is consistent with the view that separation of control from ownership allows controlling shareholders to engage in tunneling and other behaviors that increase the risk of default. State ownership weakens this positive link because government debt guarantees mitigate the risk of default. Greater competition in the banking industry generally reduces the cost of debt for non-state enterprises while having no effect for state enterprises. At the same time, greater bank competition amplifies the positive effect of ownership and control separation on debt cost for non-state enterprises as banks must still cover the higher default risk. Finally, the global financial crisis raised the cost of debt for non-state enterprises but had no effect for state enterprises.  相似文献   
28.
以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。  相似文献   
29.
《The World Economy》2018,41(5):1378-1414
This paper investigates the impact of US Export‐Import Bank (EXIM ) on US exports particularly in the wake of international competition from foreign national export credit agencies (ECA s). We employ a gravity framework on a country‐industry‐year‐level panel data set that matches EXIM authorisations with US bilateral exports. Our results depict the general ineffectiveness of the Bank in promoting exports within and across industries. Some heterogeneities behind the general finding are also uncovered: industries other than aerospace parts and products are more likely to benefit from EXIM authorisations, and EXIM authorisations to larger businesses seem to be more effective in encouraging exports. Furthermore, we find no evidence that EXIM encourages US exports by offsetting foreign ECA competition. These results are neither affected by competing countries’ membership to the OECD Arrangement nor by the size of American firms that received EXIM support. Our results cast doubt on the ubiquitously positive claims made by the Bank and its supporters, yet also provide policy lessons for countries that are either in the inception stages of establishing their own ECA s or are now placing greater importance on ECA financing in encouraging exports.  相似文献   
30.
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