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出行者的选择行为分析是交通系统中的一项重要内容,随着城市的发展,交通出行方式大体分为三大类:公共交通出行、辅助公共交通出行和私人交通出行。本文在以往的研究基础上,采用演化博弈的方法研究公共交通、共享汽车以及私家车三者之间的博弈关系,模拟出行者的选择行为,分析博弈均衡点稳定性及参数条件。通过模型仿真实验,演化结果中各项比例大小取决于各项收益、补贴、损失以及额外收益,要增加公共交通的配套设施,增收拥堵费以及增加对共享汽车的补贴及配套服务。 相似文献
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基于杭州城西9个街区1 365份大型超市出行数据,利用居民个体属性、出行距离和土地利用特征3组变量,构建了多项逻辑斯蒂克决策模型,分析了街区土地利用特征对大型超市出行模式的影响.结论为大城市街区的“可达性提高”和“商住混合度增加”,可以明显提高大型超市出行的步行(2 km内)、自行车(4 km内)选择概率;公交服务水平的提升可鼓励大型超市出行的非机动化,但公交密度本身不足以抑制小汽车的选择.提出在“社区商圈”尺度中,有必要遵循空间组织的渐进规划思路,通过“土地利用-交通”一体化措施,优化大型超市的出行结构. 相似文献
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This paper models and solves a capacitated version of the Non-Preemptive Swapping Problem. This problem is defined on a complete digraph G=(V,A), at every vertex of which there may be one unit of supply of an item, one unit of demand, or both. The objective is to determine a minimum cost capacitated vehicle route for transporting the items in such a way that all demands are satisfied. The vehicle can carry more than one item at a time. Three mathematical programming formulations of the problem are provided. Several classes of valid inequalities are derived and incorporated within a branch-and-cut algorithm, and extensive computational experiments are performed on instances adapted from TSPLIB. 相似文献
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Most solution methods for the vehicle routing problem with time windows (VRPTW) develop routes from the earliest feasible departure time. In practice, however, temporary traffic congestion make such solutions non-optimal with respect to minimizing the total duty time. Furthermore, the VRPTW does not account for driving hours regulations, which restrict the available travel time for truck drivers. To deal with these problems, we consider the vehicle departure time optimization (VDO) problem as a post-processing of a VRPTW. We propose an ILP formulation that minimizes the total duty time. The results of a case study indicate that duty time reductions of 15% can be achieved. Furthermore, computational experiments on VRPTW benchmarks indicate that ignoring traffic congestion or driving hours regulations leads to practically infeasible solutions. Therefore, new vehicle routing methods should be developed that account for these common restrictions. We propose an integrated approach based on classical insertion heuristics. 相似文献
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考虑实际坡度条件下, 提出了基于压力传感器的汽车重心与安全车速实时监测系统的多元力学模型. 建立了考虑车辆重心高度、路面纵横双向坡度及路面半径等因素的车辆安全车速控制力学模型, 并在三维模型分析的基础上提出监测与报警机理, 可为汽车安全系统提供安全车速与重心计算的多维力学模型, 为研制汽车安全车速实时监测系统提供了必要参数与依据. 相似文献
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In the vehicle routing literature, there is an increasing focus on time-dependent routing problems, where the time (or cost) to travel between any pair of nodes (customers, depots) depends on the departure time. The aim of such algorithms is to be able to take recurring congestion into account when planning logistics operations. To test algorithms for time-dependent routing problems, time-dependent problem data is necessary. This data usually comes in the form of three-dimensional travel time matrices that add the departure time as an extra dimension. However, most currently available time-dependent travel time matrices are not network-consistent, i.e., the travel times are not correlated both in time and in space. This stands in contrast to the behavior of real life congestion, which generally follows a specific pattern, appearing in specific areas and then affecting all travel times to and from those areas. As a result of the lack of available network-consistent travel time matrices, it is difficult to develop algorithms that are able to take this special structure of the travel time data into account. 相似文献
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拥挤收费是改善城市交通的有效手段.对拥挤收费定价的研究方法之一,就是针对固定的出行量进行收费设计.由于出行量预测不确定的因素,应针对长期出行量预测不确定的情况,利用灵敏度分析的方法,对拥挤收费定价的问题进行研究.首先研究了出行者出行的广义费用,然后考虑出行者的出行决策及出行量预测不确定的因素,给出一个拥挤收费定价模型,为交通管理者提供理论依据. 相似文献
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This paper considers the problem of locating a single facility in the presence of a line barrier that occurs randomly on a given horizontal route on the plane. The objective is to locate this new facility such that the sum of the expected rectilinear distances from the facility to the demand points in the presence of the probabilistic barrier is minimized. Some properties of the problem are reported, a solution algorithm is provided with an example problem, and some future extensions to the problem are discussed. 相似文献