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This paper investigates the economic implications of the liberalization of air transportation across the Taiwan Strait to the region's aviation industries. Our analysis suggests that (1) liberalization has brought substantial benefits to airports and airlines in Mainland China and Taiwan. Negative impacts to Hong Kong are largely compensated by traffic increase in routes linking Mainland China. (2) In general, Taiwanese airports and airlines have benefited more from liberalization compared to airports and airlines on the mainland and Hong Kong. Such asymmetric effect is due to the larger size of the Mainland Chinese aviation market, which allows Taiwanese airlines to exploit network-related benefits. (3) Our investigation suggests that foreign hub carriers and medium sized Chinese airports will benefit most from China's future liberalizations. 相似文献
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以一辆2009款丰田卡罗拉自动空调前出风口无风的故障为例,介绍其自动空调系统的基本组成、工作原理、各主要部件的功用以及故障检修方法。 相似文献
115.
In order to explore the control method of the intake air state in utility tunnels when the outside fresh air humidity is too high, taking the ventilation works of a utility tunnel section in Pingtan comprehensive experimental area as the research background, this paper proposes the control method of intake air state parameters for ventilation and dehumidification in utility tunnels under normal and accident conditions, by means of the effective ventilation and dehumidification duration prediction model, the evolutionary multi-objective algorithm (EMOA), and in combination with the ventilation control requirements. The results show that the intake air state parameter controller can be adjusted freely according to the different requirements of decision makers for ventilation fan working duration and dehumidifier working temperature and moisture content, and the optimized appropriate control objectives can be achieved, which is conducive to the real-time decision-making of the intake air state parameter control for ventilation and dehumidification in utility tunnels. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
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We estimate the effect of a road pricing policy introduced in Milan in 2008 on concentrations of benzene, carbon monoxide, particulates, nitrogen dioxide and sulphur dioxide. We found a sizeable effect of the Ecopass on air quality in terms of reduction in the concentration of carbon monoxide and particulates a few days after its introduction, although this effect disappeared after only one week. We interpret these results as indicative of an inefficient policy design: motorbikes were not charged and the treated area is too limited to generate positive outcomes for the whole city. Further evidence from a natural experiment given by a temporary suspension of the charge in 2012 confirms our hypothesis on the incentives for motorbike usage. 相似文献
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A moving sidewalk system installed at an airport pier finger is analyzed. The optimal length of the moving sidewalk and the optimal spacing between the access points which minimize the total cost of the system are obtained using methods of calculus, for a number of cases based on the different proportions of arriving, departing and transferring passengers and for two different types of moving sidewalks: elevated, at‐grade. The optimal length of the moving sidewalk is shown to be linearly related to the length of the concourse, and to the total passenger demand. The effect due to preticketed transferees is insignificant. The optimal spacing between access points is shown to be proportional to the square‐root of either the cost of an access escalator or the cost of inconvenience to a passenger due to an intermediate gap, depending on the moving sidewalk system under consideration. It also changes with the percentage of preticketed transferees. 相似文献
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In an earlier work, Sun and Bayen built a Large-Capacity Cell Transmission Model for air traffic flow management. They formulated an integer programming problem of minimizing the total travel time of flights in the National Airspace System of the United States subject to sector capacity constraints. The integer program was relaxed to a linear program for computational efficiency. In this paper the authors formulate the optimization problem in a standard linear programming form. We analyze the total unimodular property of the constraint matrix, and prove that the linear programming relaxation generates an optimal integral solution for the original integer program. It is guaranteed to be optimal and integral if solved by a simplex related method. In order to speed up the computation, we apply the Dantzig–Wolfe Decomposition algorithm, which is shown to preserve the total unimodularity of the constraint matrix. Finally, we evaluate the performances of Sun and Bayen’s relaxation solved by the interior point method and our decomposition algorithm with large-scale air traffic data. 相似文献
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针对某中型客车,利用ADAMS软件建立了空气悬架客车动力学仿真模型,并进行了随机路面输入及三角凸台路面输入的平顺性仿真分析。仿真结果与试验数据对比表明,在测量点处的最大加速度、自功率谱密度及其对应的频率点比较接近,说明所建立的仿真模型是准确的。对影响客车平顺性的2个参数在ADAMS中进行了优化。 相似文献
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