This paper uses empirical traffic data collected from three locations in Europe and the US to reveal a three-phase fundamental diagram with two phases located uncongested regime. Model-based clustering, hypothesis testing regression analyses are applied speed–flow–occupancy relationship represented three-dimensional space rigorously validate identify their gaps. The finding is consistent across...

Abstract Urban rail transit often operates with high service frequencies to serve heavy passenger demand during rush hours. Such operations can be delayed by two types of congestion: train congestion and congestion, both which interact each other. This delay is problematic for many systems, since it amplified due the interaction. However, there are no tractable models describing them; makes dif...

A recent study reported that the Macroscopic Fundamental Diagram of a medium size city exhibited a clockwise hysteresis loop on a day in which a major disturbance caused many drivers to switch to unfamiliar routes. This paper shows that clockwise loops are to be expected when there are disturbances, especially if the disturbances cause a significant fraction of the drivers to not change routes ...

Congestion pricing schemes have been traditionally derived based on analytical representations of travel demand and traffic flows, such as in bottleneck models. A major limitation of these models, especially when applied to urban networks, is the inconsistency with traffic dynamics and related phenomena such as hysteresis and the capacity drop. In this study we propose a new method to derive ti...

Traffic control requires looking at traffic models of all types in finer details. This paper is to investigate lane-wise flow-density (or equivalently speed-density) relationship which is traditionally called Fundamental Diagram (FD) over a stretch of homogeneous freeway section using the microscopic NGSIM data. Particularly, it investigates how a homogenous traffic further drop (breakdown) thr...

Greenshields [13] captures the empirical relation between speed, flow and density for uninterrupted traffic in the fundamental diagram, see Figure 1. Mathematical models for uninterrupted traffic have been developed and the fundamental diagram in its basic form is now well-understood, see e.g. Newell [29, 30, 31] for a concise exposition. Traffic jams are a major concern for highway operation a...

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