共查询到20条相似文献,搜索用时 0 毫秒
1.
E. H. Nugrahani 《PAMM》2007,7(1):2150033-2150034
The behavior of traffic systems controlled by traffic lights on a single lane is presented using the optimal velocity model. The effect of different traffic light control strategies on the traffic flow is discussed using three different strategies, i.e. the synchronized, green wave, and random offset. Some simulation results on the model using cellular automata are presented. The flow-density diagrams are analyzed using these strategies. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
2.
F. Siebel W. Mauser 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(1):83-97
We present a new numerical code which solves the Lighthill – Whitham model, the classic macroscopic model for vehicular traffic flow, in a network with multi-destinations. We use a high-resolution shock-capturing scheme with approximate Riemann solver to solve the partial differential equations of the Lighthill – Whitham theory. These schemes are very efficient, robust and moreover well adapted to simulations of traffic flows. We develop a theory of dynamic routing including a procedure for traffic flow assignment at junctions which reproduces the correct propagation of irregularities and ensures at the same time conservation of the number of vehicles. 相似文献
3.
We prove the existence and uniqueness of a continuous solution F = φ + w of the initial-value problem for vehicular traffic according to the nonlinear Prigogine-Herman model, where φ is a suitable t- and x-independent car distribution.We then show that the perturbation w is strongly continuous and strongly differentiable any number of times with respect to the probability of not passing q. Moreover, the derivatives (in the strong sense) satisfy linear systems.We finally investigate the behavior of w(t) as t → + ∞ and, under the assumption that the probability of not passing remains unchanged after the instant t = 0, we prove that lim ∥w(t)∥ = 0 as t → + ∞. 相似文献
4.
5.
《Applied Mathematics Letters》2006,19(9):908-912
This work deals with a two-scale vehicular traffic model, where the mass conservation equation is closed by a velocity probability distribution, parameterized with respect to each density of vehicles. The above probability distribution is identified on the basis of both experimental information and theoretical conjectures. 相似文献
6.
7.
This paper deals with the identification of the parameters of a model of vehicular traffic flow using experimental data obtained on the highway Padova–Venezia. Subsequently, simulations of the model are developed corresponding to steady uniform flow conditions. These simulations allow us to describe the velocity distribution in the above conditions corresponding to the parameters obtained by identification on the basis of experimental data. 相似文献
8.
Rinaldo M. Colombo Francesca Marcellini 《Mathematical Methods in the Applied Sciences》2015,38(7):1292-1302
We present a traffic flow model consisting of a gluing between the Lighthill–Whitham and Richards macroscopic model with a first‐order microscopic following the leader model. The basic analytical properties of this model are investigated. Existence and uniqueness are proved, as well as the basic estimates on the dependence of solutions from the initial data. Moreover, numerical integrations show some qualitative features of the model, in particular the transfer of information among regions where the different models are used. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
9.
《Applied Mathematical Modelling》2005,29(11):1054-1072
A merge is a point of a highway where two or more streams of traffic flow into one. It is always easy to solve the demand–supply problem at a merge when the merge is operating under uncongested condition. However, when congestion backs up exceeding the merging point where multiple streams of traffic meet, one is typically faced with splitting downstream supply among the merging branches. Solutions of this situation are multiple and several merge queuing models have been proposed in the past. To address the drawbacks of the past models, this paper proposes a capacity-based weighted fair queuing (CBWFQ) model that is characterized by its fidelity (approximation to real situation), simplicity, and extensibility. Based on the CBWFQ merge queuing model, a simplified kinematic wave model is formulated to model traffic operation at a merge bottleneck. 相似文献
10.
In this paper we consider an open queueing network having multiple classes, priorities, and general service time distributions.
In the case where there is a single bottleneck station we conjecture that normalized queue length and sojourn time processes
converge, in the heavy traffic limit, to one-dimensional reflected Brownian motion, and present expressions for its drift
and variance. The conjecture is motivated by known heavy traffic limit theorems for some special cases of the general model,
and some conjectured “Heavy Traffic Principles” derived from them.
Using the known stationary distribution of one-dimensional reflected Brownian motion, we present expressions for the heavy
traffic limit of stationary queue length and sojourn time distributions and moments. For systems with Markov routing we are
able to explicitly calculate the limits. 相似文献
11.
12.
Motivated by the similarity between the fundamental diagram of vehicular traffic and the Maxwell–Boltzmann distribution of ideal gases, this paper proposed a methodology to model the fundamental diagram as a stochastic process which also applies to other real-world systems with similar nature. A concrete example is provided to illustrate the application of the methodology where the fundamental diagram of vehicular traffic is modeled as a stochastic process to capture the scattering effect in flow–density relationship. A verification study was conducted on the model using empirical data and the statistical analysis shows that the overall quality of the fitted stochastic process is acceptable. Related existing efforts are referenced to the proposed stochastic fundamental diagram where their similarities and differences are elaborated. Further discussion is carried out on the significance of the stochastic fundamental diagram as well as the proposed methodology with an additional real-world example to illustrate its applications. 相似文献
13.
14.
《Mathematical and Computer Modelling》2002,35(5-6):591-606
In the present paper, a kinetic model for vehicular traffic is presented and investigated in detail. For this model, the stationary distributions can be determined explicitly. A derivation of associated macroscopic traffic flow equations from the kinetic equation is given. The coefficients appearing in these equations are identified from the solutions of the underlying stationary kinetic equation and are given explicitly. Moreover, numerical experiments and comparisons between different macroscopic models are presented. 相似文献
15.
E. Dal Santo M. D. Rosini N. Dymski M. Benyahia 《Mathematical Methods in the Applied Sciences》2017,40(18):6623-6641
In this paper, we present a general phase transition model that describes the evolution of vehicular traffic along a one‐lane road. Two different phases are taken into account, according to whether the traffic is low or heavy. The model is given by a scalar conservation law in the free‐flow phase and by a system of 2 conservation laws in the congested phase. The free‐flow phase is described by a one‐dimensional fundamental diagram corresponding to a Newell‐Daganzo type flux. The congestion phase is described by a two‐dimensional fundamental diagram obtained by perturbing a general fundamental flux. In particular, we study the resulting Riemann problems in the case a local point constraint on the flow of the solutions is enforced. 相似文献
16.
This paper offers the proof of the existence for large times of the Cauchy problem for a class of vehicular traffic models with discrete velocities derived from the mathematical tools of the kinetic theory for active particles. This approach has the ability to capture some basic aspects concerning the complexity of the systems under consideration through an appropriate modeling, via stochastic games, of the interactions at the microscopic scale. The proof is related to specific aspects of the real system and hopefully can contribute towards improving the modeling approach. 相似文献
17.
This work deals with the derivation and the analysis of a new mathematical model for vehicular traffic along a one-way road obtained by the coupling of a uniform and an adaptive discretization of the velocity variable in the framework of the kinetic theory. Interactions are modelled by stochastic games where the output of interactions depends on the local density and is not linearly additive. 相似文献
18.
19.
A. N. Sesekin A. A. Chentsov A. G. Chentsov 《Proceedings of the Steklov Institute of Mathematics》2011,272(1):165-185
An extremal routing problem with a criterion that has the sense of the largest edge length of a polygonal line is considered. It is assumed that the costs at every step (stage) of the travel may depend on a list of tasks that have not been fulfilled by the beginning of this step. In addition, there are constraints in the form of precedence conditions. An economical variant of the procedure is constructed based on the dynamic programming method. 相似文献
20.
Jong-Shi Pang Lanshan Han Gitakrishnan Ramadurai Satish Ukkusuri 《Mathematical Programming》2012,133(1-2):437-460
This paper formally introduces a linear complementarity system (LCS) formulation for a continuous-time, multi-user class, dynamic user equilibrium (DUE) model for the determination of trip timing decisions in a simplified single bottleneck model. Existence of a Lipschitz solution trajectory to the model is established by a constructive time-stepping method whose convergence is rigorously analyzed. The solvability of the time-discretized subproblems by Lemke’s algorithm is also proved. Combining linear complementarity with ordinary differential equations and being a new entry to the mathematical programming field, the LCS provides a computational tractable framework for the rigorous treatment of the DUE problem in continuous time; this paper makes a positive contribution in this promising research venue pertaining to the application of differential variational theory to dynamic traffic problems. 相似文献