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131.
为科学管理共享停车资源,构建一种共享停车泊位的分配-定价-收益分配机制。首先,以存在多个地块的区域为对象,根据出行者对不同地块及停车时间模式的选择偏好构建停车许可证的最优分配-定价模型,其中,最优分配模型为组合拍卖竞胜标确定问题(NP困难问题)。其次,利用Benders分解原理、对偶理论及新型升价拍卖代理系统构建调优法对停车许可证进行拍卖。最后,为调动共享泊位提供者的积极性,利用沙普利值法构建基于对社会福利贡献程度的停车收益分配模型。由理论分析及数值试验可知,运用上述机制可精确实现社会福利最优状态,最小竞争均衡价格与公平的收益分配。结果表明:①相较VCG机制与Leonard机制,调优法不仅可精确求解停车许可证的最优分配-定价,而且在算法最坏时间复杂度方面拥有更高效率;②在调优法的每个步骤中,即使停车许可证的分配并非最优,通过机制所实现的收费定价依然具有防止策略性操作的重要性质;③调优法可在较少的步骤之内实现较高的社会福利;④新型升价拍卖代理系统拥有多项式型的最坏时间复杂度;⑤通过最优分配-定价机制可获得每位出行者的选择偏好,进而可计算不同泊位提供者组合条件下的社会福利,实现沙普利值法在现实应用中的可计算性。 相似文献
132.
The impacts of the already decided increase in rail infrastructure charges in Sweden are described for various market segments within the rail transport system and on the aggregate level for society as a whole. The need for complementary measures in the road transport system is also discussed. Likewise, the paper also mentions the impact of increased rail infrastructure charges on certain significant industrial sectors. An increase in rail charges may reduce social welfare even though the reduction in rail transport mileage is small. This is mainly due to large non-internalised absolute externalities for road freight. For commuter trains, the infrastructure charges' share of the costs of rail transport is expected to rise to 13 percent, which in an international perspective still will be small. 相似文献
133.
道路拥挤定价下的公交收费模型研究 总被引:3,自引:2,他引:3
为了在执行道路拥挤定价政策的前提下制定公共交通的收费标准,提出可行的定价模型,根据交通行为科学的有关理论和方法,采用了两层规划技术建立了道路拥挤定价下的公交收费模型,上层规划为交通系统优化,下层规划为拥挤定价下的路网随机平衡问题。以广州市为研究对象,计算了拥挤定价下广州市公交线网的最优价格体系。研究结果表明:所提出的模型能够描述出行者和交通管理部门分别在出行和交通管理中的决策行为,较好地解释了用户平衡、路段路径流量和阻抗、交通需求、拥挤费、公交票价、出行成本等相互之间的逻辑关系。 相似文献
134.
135.
Road Pricing models with maintenance cost 总被引:2,自引:0,他引:2
According to the Federal Highway Administration of the United States, maintenance expenditure takes up more than 25% of road revenue disbursement and this percentage has been increasing gradually. The reason for the increment in maintenance cost is that there lacks incentives for road users to take this cost component into their driving behavior. That is, different classes of vehicles should be levied different levels of congestion tax due to the different degrees of damage on the highway if a road pricing policy is implemented. This paper intends to incorporate this concept into road pricing literature by introducing two types of vehicles. After the analysis of the problem, we find that different types of vehicles should be charged different tolls. The toll includes not only the travel delay cost of one's own vehicle and the other types of vehicles, but also the marginal maintenance cost that is dependent on the traffic flow. A set of numerical examples is provided to demonstrate the theoretical analyses. The result shows that both the welfare and cost coverage rate will increase when the road pricing mechanism takes the maintenance cost factor into account. 相似文献
136.
The build-operate-transfer (BOT) approach has become an attractive instrument for public facility provision, especially for a project that faces difficulty with public finance. This study analyzes the regulation alternatives on private highway investment under a BOT scheme and their impacts on traffic flows, travel costs, toll, capacity, and social welfare (total user-benefit in the traffic system including congestion). For comparison, five cases are analyzed: (1) No BOT with maximizing welfare, (2) No BOT with breaking even on finance, (3) BOT without regulation, (4) BOT with a minimum flow constraint (the total users will not be less than those in Case 1), and (5) BOT with a maximum travel cost constraint (the travel cost for users on a non-tolled road will not exceed the maximum tolerance). After each case is modeled and simulated on some functional forms, we find that the case of BOT with regulations performs between the cases of maximizing welfare and that of maximizing profit. From the perspective of the government, regulation has less power in a project with low elastic demand. Furthermore, even when the regulation is strict, a high cost-efficient firm with BOT could result in a higher level of social welfare than that without a BOT scheme. 相似文献
137.
道路收费作为交通需求管理的一种有效措施在许多国家和地区开始提倡 .笔者研究了混合交通平衡下如何制定车辆的道路收费策略 ,提出了满足Wardrop平衡原则和车种分离函数的数学模型及求解算法 ,最后给出了算例 相似文献
138.
Private provision of public infrastructure (PPP) is meant to give incentives to increased efficiency in construction as well in operation and maintenance of the infrastructure e.g. within the transport sector. Efficiency is not only (private) economic efficiency, but also social efficiency e.g. social marginal cost pricing of use of the infrastructure.Is it possible to design contracts concerning payment mechanisms and financial instruments for transport infrastructure that will stimulate social efficiency and optimal allocation of risks between parties? The paper discusses whether different targets can be met and whether compromises may lead to acceptable second best solutions.PPP implies an opportunity to let the user-payment give desired incentives in the form of Social Marginal Cost Pricing (SMCP). A PPP project is a set of contracts and agreements between several parties, including the Government, the private contractor, subcontractors, banks and infrastructure users. These contracts should be designed to give the right incentives to the parties to achieve optimal risk allocation and utilising of resources.Long contract-periods are a common feature of PPPs. The paper examines the way that financial solutions should be designed to achieve the goals for the PPP-projects concerning economic and social efficiency. The expected size and variation of the income stream from the project will influence the loan conditions offered by banks concerning interest rates, guarantees and repayment and also the ability to attract investors. The balance between equity and loans again influences the conditions of the loans. An additional problem is asymmetric information between parties. The private contractor usually knows more about the task than the Government (hidden knowledge), and the Government cannot have full knowledge of the efforts of the contractor (hidden actions). 相似文献
139.
Congestion in transport stations could result in stampede development and deadly crush situations. Closed circuit television (CCTV) cameras enable station managers to monitor the crowd and reduce overcrowding risks. However, identifying congestion conditions is a very laborious task for a human operator who has to monitor multiple locations at the same time. This paper presents a new approach to automated image-based identification of congestion as measured by level of service (LOS), which is the most widely accepted standard for measuring congestion. Existing methods for measuring LOS based on crowd density estimation from images have the disadvantages that, crowd density cannot be estimated accurately. In addition, the calculation of flow parameters involves a complex process, and consequently these parameters are not indicative of congestion in real-time. This paper proposes a novel method based on machine learning to directly classify LOS without calculating flow parameters. In the proposed method, visual features extracted by a deep convolutional neural network are classified using a support vector machine classifier and the classification results are further refined by using a long short-term memory network. A second contribution of this research is to develop a web-based LOS map visualization platform to monitor pedestrian distribution and variation of distribution in real-time. Experimental evaluation at Flinders Street Station in Melbourne shows that this method can achieve an accuracy of 81.9% and efficiency of 0.40?seconds per frame in LOS classification using CCTV images. 相似文献
140.
在复合期权的定价研究中,Geske(1979)公式的不足之处在于其假设利率和波动率均为常数.Geman-El Karoui-Rochet(1995)、Hull(1998,2000)等人也是假设波动率或利率之一为常数.本文对Geske公式加以推广,得出了利率和波动率都随机波动时的复合期权定价公式,具有更强的实践意义. 相似文献