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Ludovic Leclercq - One of the best experts on this subject based on the ideXlab platform.
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multiscale traffic flow model based on the mesoscopic Lighthill whitham and richards models
Transportation Research Record, 2015Co-Authors: Mahtab Joueiai, Ludovic Leclercq, Hans Van Lint, S P HoogendoornAbstract:This article reviews the multiscale modeling concept as an adaptive strategy in traffic flow modeling. The central objective for the multiscale model is to describe and to predict traffic phenomena (e.g., individual accelerations, queuing) that occur at different scales by switching between modeling paradigms. The emphasis in this paper is placed on resolving inconsistencies that arise in the process of integrating models, which are addressed with the mesoscopic Lighthill–Whitham and Richards models—together, widely known as the Lighthill–Whitham–Richards (LWR) model—as the coarse-scale model in the framework. The mesoscopic model is fully consistent at the macroscopic scale with the classic LWR model but does facilitate tracking of individual vehicles. Because of this characteristic, this model can be combined with microscopic models, because no disaggregation or aggregation process is needed. It is thus implied, for example, that travel information (e.g., destination) can be carried over this model with...
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meso Lighthill whitham and richards model designed for network applications
Transportation Research Board 91st Annual MeetingTransportation Research Board, 2012Co-Authors: Ludovic Leclercq, Cecile BecarieAbstract:The aim of this paper is to propose a new event-based mesoscopic model, fully consistent at a macroscopic scale with the LWR model. This model is parsimonious, has a low computational cost while keeping an individual tracking of vehicles. It is ready for dynamic traffic assignment applications. It can also be easily hybrided with any microscopic models to propose a bi-level traffic flow representation on networks. This model revisits the link traffic flow model early proposed by Mahut (2003) by integrating heterogeneous vehicle characteristics and moving bottlenecks treatment. It also introduces a simple node model that (i) generalizes the supply allocation scheme at merges proposed by Daganzo (ii) naturally respects the FIFO rules at diverges and (iii) accounts for traffic signals timing. This model adapts to a vehicular description the global behavior reproduced by classical macroscopic nodes models and notably merge ratios.
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moving bottlenecks in Lighthill whitham richards model a unified theory
Transportation Research Record, 2004Co-Authors: Ludovic Leclercq, Stephane Chanut, J B LesortAbstract:A unified general framework for the moving-bottleneck models based on the Lighthill-Whitham-Richards theory is proposed. It is shown that all existing models may be considered as particular cases of the general model, differing only by the phenomenology involved, that is, by the shape of the flow-density relationship used for the restricted section. Possible generalization of the model through various flow-density relationships is discussed, as well as the possibilities of experimental validation.
Uday Narayan Ghosh - One of the best experts on this subject based on the ideXlab platform.
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the effect of q distributed electrons on the head on collision of ion acoustic solitary waves
Physics of Plasmas, 2012Co-Authors: Uday Narayan Ghosh, Prasanta Chatterjee, Rajkumar RoychoudhuryAbstract:The head-on collision of ion acoustic solitary waves (IASWs) in two component plasma comprising nonextensive distributed electrons is investigated. Two opposite directional Kortewg-de-vries (KdV) equations are derived and the phase shift due to collision is obtained using the extended version of Poincare-Lighthill-Kuo method. Different ranges of nonextensive parameter q are considered and their effects on phase shifts are observed. It is found that the presence of nonextensive distributed electrons plays a significant role on the nature of collision of ion acoustic solitary waves.
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head on collision of ion acoustic solitary waves in electron positron ion plasma with superthermal electrons and positrons
European Physical Journal D, 2011Co-Authors: Prasanta Chatterjee, Uday Narayan GhoshAbstract:The head-on collision of ion acoustic solitary waves are studied in an electron-positron-ion plasma composed of superthermal electrons, superthermal positrons, and cold ions using the extended Poincare-Lighthill-Kuo (PLK) method. The effects of the ratio of electron to positron temperature, the spectral index of electron and positron, and the concentration of positron component on the phase shift are studied. It is found that the presence of superthermal electrons and superthermal positrons play a significant role on the collision of ion acoustic solitary waves. It is also been observed that the temperature ratio plays a significant role on the collision of ion acoustic solitary waves.
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head on collision of ion acoustic solitary waves in an electron positron ion plasma with superthermal electrons
Physics of Plasmas, 2010Co-Authors: Prasanta Chatterjee, Uday Narayan Ghosh, S V Muniandy, C S Wong, Biswajit SahuAbstract:The head-on collision of ion acoustic solitary waves in a three-component unmagnetized plasma with cold ions, Boltzmann distributed positrons, and superthermal electrons is investigated using the extended Poincare–Lighthill–Kuo method. The effects of the ratio of electron temperature to positron temperature, the spectral index, κ, of the electron kappa distribution, and fractional concentration of positron component (p) on the phase shift are studied. It is found that the presence of superthermal electrons play a significant role on the collision of ion acoustic solitary waves.
Prasanta Chatterjee - One of the best experts on this subject based on the ideXlab platform.
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head on collision of dust ion acoustic solitary waves in magnetized quantum dusty plasmas
Astrophysics and Space Science, 2013Co-Authors: Malay Kumar Ghorui, Prasanta Chatterjee, C S WongAbstract:The Head on collision of dust ion acoustic solitary waves (DIASWs) in a magnetized quantum dusty plasma is investigated. Two sides Korteweg-de Vries (KdV) equations are obtained, the analytical phase shifts and the trajectories after the head-on collision of two DIASWs in a three species quantum dusty plasma are derive by using the extended version of Poincare-Lighthill-Kuo (PLK) method. It is observed that the phase shifts are significantly affected by the quantum parameters like quantum diffraction, the ion cyclotron frequency and the ratio of the densities of electrons to ions.
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the effect of q distributed electrons on the head on collision of ion acoustic solitary waves
Physics of Plasmas, 2012Co-Authors: Uday Narayan Ghosh, Prasanta Chatterjee, Rajkumar RoychoudhuryAbstract:The head-on collision of ion acoustic solitary waves (IASWs) in two component plasma comprising nonextensive distributed electrons is investigated. Two opposite directional Kortewg-de-vries (KdV) equations are derived and the phase shift due to collision is obtained using the extended version of Poincare-Lighthill-Kuo method. Different ranges of nonextensive parameter q are considered and their effects on phase shifts are observed. It is found that the presence of nonextensive distributed electrons plays a significant role on the nature of collision of ion acoustic solitary waves.
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head on collision of ion acoustic solitary waves in electron positron ion plasma with superthermal electrons and positrons
European Physical Journal D, 2011Co-Authors: Prasanta Chatterjee, Uday Narayan GhoshAbstract:The head-on collision of ion acoustic solitary waves are studied in an electron-positron-ion plasma composed of superthermal electrons, superthermal positrons, and cold ions using the extended Poincare-Lighthill-Kuo (PLK) method. The effects of the ratio of electron to positron temperature, the spectral index of electron and positron, and the concentration of positron component on the phase shift are studied. It is found that the presence of superthermal electrons and superthermal positrons play a significant role on the collision of ion acoustic solitary waves. It is also been observed that the temperature ratio plays a significant role on the collision of ion acoustic solitary waves.
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head on collision of ion acoustic solitary waves in an electron positron ion plasma with superthermal electrons
Physics of Plasmas, 2010Co-Authors: Prasanta Chatterjee, Uday Narayan Ghosh, S V Muniandy, C S Wong, Biswajit SahuAbstract:The head-on collision of ion acoustic solitary waves in a three-component unmagnetized plasma with cold ions, Boltzmann distributed positrons, and superthermal electrons is investigated using the extended Poincare–Lighthill–Kuo method. The effects of the ratio of electron temperature to positron temperature, the spectral index, κ, of the electron kappa distribution, and fractional concentration of positron component (p) on the phase shift are studied. It is found that the presence of superthermal electrons play a significant role on the collision of ion acoustic solitary waves.
S P Hoogendoorn - One of the best experts on this subject based on the ideXlab platform.
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multiscale traffic flow model based on the mesoscopic Lighthill whitham and richards models
Transportation Research Record, 2015Co-Authors: Mahtab Joueiai, Ludovic Leclercq, Hans Van Lint, S P HoogendoornAbstract:This article reviews the multiscale modeling concept as an adaptive strategy in traffic flow modeling. The central objective for the multiscale model is to describe and to predict traffic phenomena (e.g., individual accelerations, queuing) that occur at different scales by switching between modeling paradigms. The emphasis in this paper is placed on resolving inconsistencies that arise in the process of integrating models, which are addressed with the mesoscopic Lighthill–Whitham and Richards models—together, widely known as the Lighthill–Whitham–Richards (LWR) model—as the coarse-scale model in the framework. The mesoscopic model is fully consistent at the macroscopic scale with the classic LWR model but does facilitate tracking of individual vehicles. Because of this characteristic, this model can be combined with microscopic models, because no disaggregation or aggregation process is needed. It is thus implied, for example, that travel information (e.g., destination) can be carried over this model with...
Paola Goatin - One of the best experts on this subject based on the ideXlab platform.
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Comparative study of macroscopic traffic flow models at road junctions
Networks and Heterogeneous Media, 2020Co-Authors: Paola Goatin, Elena RossiAbstract:We qualitatively compare the solutions of a multilane model with those produced by the classical Lighthill-Whitham-Richards equation with suitable coupling conditions at simple road junctions. The numerical simulations are based on the Godunov and upwind schemes. Several tests illustrate the models' behaviour in different realistic situations.
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Uncertainty quantification in a macroscopic traffic flow model calibrated on GPS data
Mathematical Biosciences and Engineering, 2020Co-Authors: Enrico Bertino, Régis Duvigneau, Paola GoatinAbstract:The objective of this paper is to analyze the inclusion of one or more random parameters into the deterministic Lighthill-Whitham-Richards traffic flow model and use a semi-intrusive approach to quantify uncertainty propagation. To verify the validity of the method, we test it against real data coming from vehicle embedded GPS systems, provided by Autoroutes Trafic.
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The Lighthill-Whitham- Richards traffic flow model with non-local velocity: analytical study and numerical results
2015Co-Authors: Paola Goatin, Sheila ScialangaAbstract:We consider an extension of the classical Lighthill-Whitham-Richards traffic flow model, in which the mean velocity is assumed to be dependent on the downstream traffic density. We generalize the results of [BlandinGoatin] to a general velocity function v, and propose a second order numerical scheme to compute approximate solutions.
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the aw rascle vehicular traffic flow model with phase transitions
Mathematical and Computer Modelling, 2006Co-Authors: Paola GoatinAbstract:We introduce a new model of vehicular traffic flow with phase transitions. The model is obtained by coupling together the classical Lighthill-Whitham-Richards equation with the 2x2 system proposed by Aw and Rascle. This allows us both to correct some drawbacks of the original 2x2 system, and to obtain results that fit experimental data well. We describe the solutions of the Riemann problem, and we compare the results with those obtained using other models.