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The paper characterizes the behavior of the cell transmission model of a freeway, divided into N sections or cells, each with one on-ramp and one off-ramp. The state of the dynamical system is the N-dimensional vector n of vehicle densities in the N sections. A feasible stationary demand pattern induces a unique equilibrium flow in each section. However,(More)
The onramp metering control problem is posed using a cell transmission-like model called the asymmetric cell transmission model (ACTM). The problem formulation captures both freeflow and congested conditions, and includes upper bounds on the metering rates and on the onramp queue lengths. It is shown that a near-global solution to the resulting nonlinear(More)
We present a method for automated, empirical calibration of freeway traffic flow characteristics. The method uses 5-min flow and density values for a section of freeway and rapidly and reliably estimates key parameters such as free flow speed, capacity, critical density, congestion wave speed and jam density, which are key inputs to many macroscopic traffic(More)
TOPL is a suite of software tools for specifying freeway operational improvement strategies, such as ramp metering, demand and incident management, and for quickly estimating the benefits of such improvements. TOPL is based on the macroscopic cell transmission model. The paper summarizes the theory of the cell transmission model and describes the procedure(More)
A mathematical programming approach to the freeway on-ramp metering problem is formulated. The objective function is a linear combination of mainline and on-ramp flows, termed the generalized total travel time. The underlying freeway model - the asymmetric cell transmission model (ACTM) - is similar to the original cell transmission model (CTM), except that(More)
The contents of this report refl ect the views of the authors who are re spon si ble for the facts and the accuracy of the data pre sent ed herein. The con tents do not necessarily refl ect the offi cial views or policies of the State of Cal i for nia. This report does not constitute a standard, spec i fi ca tion, or regulation. Abstract This dissertation(More)
An advanced machine vision system is presented that automatically extracts vehicle trajectories over long freeway sections from video data. For each vehicle, its dimension and initial position are robustly given by the vehicle detection algorithm, and a separate tracking algorithm is used to extract the vehicle's trajectory from the images of multiple(More)