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441.
Travel time, travel time reliability and monetary cost have been empirically identified as the most important criteria influencing route choice behaviour. We concentrate on travel time and travel time reliability and review two prominent user equilibrium models incorporating these two factors. We discuss some shortcomings of these models and propose alternative bi-objective user equilibrium models that overcome the shortcomings. Finally, based on the observation that both models use standard deviation of travel time within their measure of travel time reliability, we propose a general travel time reliability bi-objective user equilibrium model. We prove that this model encompasses those discussed previously and hence forms a general framework for the study of reliability related user equilibrium. We demonstrate and validate our concepts on a small three-link example. 相似文献
442.
This study proposes a coordinated online in-vehicle routing mechanism for smart vehicles with real-time information exchange and portable computation capabilities. The proposed coordinated routing mechanism incorporates a discrete choice model to account for drivers’ behavior, and is implemented by a simultaneously-updating distributed algorithm. This study shows the existence of an equilibrium coordinated routing decision for the mixed-strategy routing game and the convergence of the distributed algorithm to the equilibrium routing decision, assuming individual smart vehicles are selfish players seeking to minimize their own travel time. Numerical experiments conducted based on Sioux Falls city network indicate that the proposed distributed algorithm converges quickly under different smart vehicle penetrations, thus it possesses a great potential for online applications. Moreover, the proposed coordinated routing mechanism outperforms traditional independent selfish-routing mechanism; it reduces travel time for both overall system and individual vehicles, which represents the core idea of Intelligent Transportation Systems (ITS). 相似文献
443.
随着我国现代化城市聚集性发展,城市居民越来越多,由于出行需要,容易集中聚集到中心城区的商业圈内,极易出现交通拥堵和停车困难的问题.本文针对现在城市商圈普遍存在的车位紧张,停车困难的问题,希望通过引入停车诱导系统,通过对停车车辆和车位信息进行收集整理,并反馈引导车辆驾驶员,在商圈内进行更高效的停车.从而改善商圈停车环境,... 相似文献
444.
This paper aims to develop a hybrid closed-form route choice model and the corresponding stochastic user equilibrium (SUE) to alleviate the drawbacks of both Logit and Weibit models by simultaneously considering absolute cost difference and relative cost difference in travelers’ route choice decisions. The model development is based on an observation that the issues of absolute and relative cost differences are analogous to the negative exponential and power impedance functions of the trip distribution gravity model. Some theoretical properties of the hybrid model are also examined, such as the probability relationship among the three models, independence from irrelevant alternatives, and direct and indirect elasticities. To consider the congestion effect, we provide a unified modeling framework to formulate the Logit, Weibit and hybrid SUE models with the same entropy maximization objective but with different total cost constraint specifications representing the modelers’ knowledge of the system. With this, there are two ways to interpret the dual variable associated with the cost constraint: shadow price representing the marginal change in the entropy level to a marginal change in the total cost, and dispersion/shape parameter representing the travelers’ perceptions of travel costs. To further consider the route overlapping effect, a path-size factor is incorporated into the hybrid SUE model. Numerical examples are also provided to illustrate the capability of the hybrid model in handling both absolute and relative cost differences as well as the route overlapping problem in travelers’ route choice decisions. 相似文献
445.
When drivers do not have complete information on road travel time and thus choose their routes in a stochastic manner or based on their previous experience, separate implementations of either route guidance or road pricing cannot drive a stochastic network flow pattern towards a system optimum in a Wardropian sense. It is thus of interest to consider a combined route guidance and road pricing system. A road guidance system could reduce drivers' uncertainty of travel time through provision of traffic information. A driver who is equipped with a guidance system could be assumed to receive complete information, and hence be able to find the minimum travel time routes in a user-optimal manner, while marginal-cost road pricing could drive a user-optimal flow pattern toward a system optimum. Therefore, a joint implementation of route guidance and road pricing in a network with recurrent congestion could drive a stochastic network flow pattern towards a system optimum, and thus achieve a higher reduction in system travel time. In this paper the interaction between route guidance and road pricing is modeled and the potential benefit of their joint implementation is evaluated based on a mixed equilibrium traffic assignment model. The private and system benefits under marginal-cost pricing and varied levels of market penetration of the information systems are investigated with a small and a large example. It is concluded that the two technologies complement each other and that their joint implementation can reduce travel time more efficiently in a network with recurrent congestion. 相似文献
446.
河都高速公路顺安至高岭段项目地形复杂、工程量艰巨,路线布设困难,如何选择最优的路线方案,是河都高速公路勘察设计要突破的重点和难点。文章结合工程概况拟定了两种路线方案,并从工程地质条件、工程规模、占地拆迁、营运效益和工程造价等方面对这两种方案进行比较,选出推荐使用的路线方案。 相似文献
447.
现实生活中,驾驶员往往依据自身偏好来选择路径,对不同的路径属性有不同的要求,且对其属性值存在一个可接受范围,而不是一个精确值. 本文对存在驾驶员偏好的最优路径选择问题进行了研究,提出了一种能够综合反映驾驶员偏好的最优路径选择方法. 首先基于可能度和区间数相离度的多属性决策方法,建立驾驶员偏好与路径属性总偏差最小的优化模型,并解出路径属性权重;其次算出各路径的综合属性值,建立路径间的可能度矩阵及其排序向量,据此选出最优路径;最后以算例进行验证,结果表明本文给出的路径选择方法具有很好的可行性和适用性. 相似文献
448.
应用非线性最优控制方法, 研究了高速公路网的匝道控制和路径诱导的集成问题, 构造了集成控制的最优控制模型。在模型中, 以路网总耗时最小为优化目标, 以METANET模型为网络交通流模型, 考虑了控制变量的更新周期约束, 采用粒子群优化技术求解优化模型。仿真结果表明: 无控制时, 路网总耗时为3376 veh·h; 仅实施匝道控制时, 路网总耗时为3005 veh·h; 仅实施路径诱导时, 路网总耗时为2768 veh·h; 集成控制时, 路网总耗时为2464 veh·h。可见, 集成控制效果最优。 相似文献
449.
450.