3,078 research outputs found

    Estimation of origin-destination matrix from traffic counts: the state of the art

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    The estimation of up-to-date origin-destination matrix (ODM) from an obsolete trip data, using current available information is essential in transportation planning, traffic management and operations. Researchers from last 2 decades have explored various methods of estimating ODM using traffic count data. There are two categories of ODM; static and dynamic ODM. This paper presents studies on both the issues of static and dynamic ODM estimation, the reliability measures of the estimated matrix and also the issue of determining the set of traffic link count stations required to acquire maximum information to estimate a reliable matrix

    Estimation of origin-destination matrix from traffic counts: the state of the art

    Get PDF
    The estimation of up-to-date origin-destination matrix (ODM) from an obsolete trip data, using current available information is essential in transportation planning, traffic management and operations. Researchers from last 2 decades have explored various methods of estimating ODM using traffic count data. There are two categories of ODM; static and dynamic ODM. This paper presents studies on both the issues of static and dynamic ODM estimation, the reliability measures of the estimated matrix and also the issue of determining the set of traffic link count stations required to acquire maximum information to estimate a reliable matrix

    Cost-effectiveness of cordon studies for trip matrix estimation from traffic counts

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    Cordon studies can substantially improve estimation of origin-destination (O/D) trip matrices from link traffic counts. This paper proposes a method for integrating cordon survey results in O/D matrix estimation. This method is applied to 5 inter-urban networks in the Valencia Region, focusing on the specific formulation of the O/D matrix estimation technique, the assignment model to be implemented, the selection of traffic count locations in the cordoned area and, especially, the selection of cordon survey stations and data collection. Cost-effectiveness of cordon survey selection is addressed. The results show that cost-effectiveness ratios tend to decrease with the number of surveyed cordons in the 5 networks analyzed. This is due to non-linear reduction of origin-destination estimation errors and economies of scale on conducting cordon surveys. The results of this study can be useful to assess decision-making when conducting cordon surveys in interurban networks. Once such decisions have been taken, the method presented in this paper can be applied to the whole O/D matrix estimation procedure.Torres Martínez, AJ. (2012). Cost-effectiveness of cordon studies for trip matrix estimation from traffic counts. http://hdl.handle.net/10251/1496

    Dispatching and Rescheduling Tasks and Their Interactions with Travel Demand and the Energy Domain: Models and Algorithms

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    Abstract The paper aims to provide an overview of the key factors to consider when performing reliable modelling of rail services. Given our underlying belief that to build a robust simulation environment a rail service cannot be considered an isolated system, also the connected systems, which influence and, in turn, are influenced by such services, must be properly modelled. For this purpose, an extensive overview of the rail simulation and optimisation models proposed in the literature is first provided. Rail simulation models are classified according to the level of detail implemented (microscopic, mesoscopic and macroscopic), the variables involved (deterministic and stochastic) and the processing techniques adopted (synchronous and asynchronous). By contrast, within rail optimisation models, both planning (timetabling) and management (rescheduling) phases are discussed. The main issues concerning the interaction of rail services with travel demand flows and the energy domain are also described. Finally, in an attempt to provide a comprehensive framework an overview of the main metaheuristic resolution techniques used in the planning and management phases is shown

    Sensitivity analysis of the variable demand probit stochastic user equilibrium with multiple user classes

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    This paper presents a formulation of the multiple user class, variable demand, probit stochastic user equilibrium model. Sufficient conditions are stated for differentiability of the equilibrium flows of this model. This justifies the derivation of sensitivity expressions for the equilibrium flows, which are presented in a format that can be implemented in commercially available software. A numerical example verifies the sensitivity expressions, and that this formulation is applicable to large networks
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