Analysis of Traffic Congestion in Urban Space and the Second-best Pricing Policies

(1)交通拥堵空间模型的建立：该模型描述了城市空间中各个位置的出行行为和交通拥堵状态。出行成本取决于出行路径上的交通拥堵，交通拥堵是道路使用者出行决策的结果。该模型被表述为包含上述因素的微分方程组。(2)单中心城市的最优警戒线定价：在单中心城市，所有行程都以CBD为目的地。我们对问题进行了描述和求解，得到了警戒线位置和收费水平的最优组合，并研究了解的性质。在最优警戒线定价下，从警戒线内的地点出发的出行价格偏低，警戒线外的出行价格过高，城市边缘地区的出行价格过低。数值模拟表明，警戒线定价达到了非常接近第一最优的经济福利水平。(3)最优…非单中心城市的更多n定价：我们建立了一个非单中心城市交通拥堵的空间模型，其中出行发生在城市中任何两个地点之间。我们评估了无收费均衡、优先最优和最优警戒线定价三种方案的经济福利。数值模拟表明，警戒线定价的有效性取决于各种因素，包括城市的空间结构和其他参数。结果表明，引入警戒线定价后，当城市空间结构接近单中心、密度梯度较大、出行需求弹性较小、道路通行能力较大时，福利改善幅度较大。(4)大阪大都市区实证分析：利用大阪大都市区的数据估计出行需求函数和出行成本函数中的参数。将网络仿真模型应用于大阪都市圈，将大阪都市圈划分为36个区域，拥有241个节点和634个路段的路网。结果表明，单一警戒线定价使社会剩余水平提高21%，三层警戒线定价使社会剩余水平提高25%。较少

(1)Development of the spatial model of traffic congestion:The model describes trip making behavior and state of traffic congestion at each location on the urban space. Trip cost depends on traffic congestion along the path of trip, and, traffic congestion is the result of trip making decisions of road users. The model is formulated as a system of differential equations incorporating the above factors.(2)Optimal cordon pricing in a monocentric city:In a monocentric city, all trips are destined to the CBD. We formulate and solve the problem to obtain the optimal combination of cordon location and toll level, and investigate the properties of the solution. Under the optimal cordon pricing, trips from locations inside the cordon are under-priced, those just outside the cordon are over-priced and those in the fringe of the urban area are under-priced. Numerical simulations suggest that the cordon pricing attains an economic welfare Level very close to the first-best optimum.(3)Optimal cordo … More n pricing in a non-monocentric city:We develop a spatial model of traffic congestion in a non-monocentric city, where trips occur between any pair of locations in a city. We evaluate the economic welfare for three schemes no-toll equilibrium, first best optimum, and optimal cordon pricing. Numerical simulations demonstrated that effectiveness of the cordon pricing depends on various factors including spatial structure of the city and other parameters. It is shown that welfare improvement by introducing the cordon pricing, tends to be large, when the urban spatial structure is close to monocentric; density gradient is steeper; trip demand is less elastic; road capacity is larger.(4)Empirical analysis for Osaka Metropolitan Area:We estimate parameters in trip demand function and trip cost function using the data for Osaka metropolitan area. We apply the network simulation model to Osaka Metropolitan Area, which is divided into 36 zones, and has the road network with 241 nodes and 634 link. It is shown that pricing at the single cordon improves the level of social surplus by 21%, and three layers cordon improves by 25%. Less