01349731

Component

http://www.trb.org/Publications/Blurbs/165625.aspx

Mesoscopic traffic simulation models combine macroscopic supply (e.g., link performance functions and capacities) with microscopic demand (e.g., individual drivers and disaggregate behavior models) to capture the time-varying evolution of congestion patterns, queues, and spillbacks on traffic networks. Such systems are being applied to solve a variety of off-line and online traffic management problems. Often, the link performance function takes the form of a speed–density relationship for each link or segment in the study network. These functions are based on the fundamental diagram and model the variation of average vehicle speed with traffic density. Since each network link or segment can have a separate speed–density function (each with a few parameters), the total number of parameters to be calibrated is potentially very large. This paper presents some experiences with calibrating speed–density functions on a variety of real networks. Flexible off-line and on-line calibration frameworks are discussed. The calibrated functions are embedded within the DynaMIT dynamic traffic assignment model, whose accuracy is evaluated against real data. The expected benefits from recalibrating speed–density functions during on-line operations using real-time sensor data are also illustrated.

01349716

English

pp 199-209

2011-6

Transportation Research Circular

Greenshields 75 Symposium

Web

Figures (2) ; Maps (2) ; References (33) ; Tables (3)

Calibration; Dynamic traffic assignment; Mesoscopic traffic flow; Network links; Operating speed; Real time information; Traffic congestion; Traffic density; Traffic flow theory; Traffic queuing; Traffic simulation

DynaMIT (Computer program)

Fundamental diagram; Speed-density relationships; Spillback effects (Traffic)

Highways; Operations and Traffic Management; I71: Traffic Theory

TRIS, TRB

Aug 15 2011 9:58AM

• A Macroscopic Fundamental Diagram of Urban Traffic: Recent Findings
• A Simple and Pragmatic Representation of Traffic Flow
• A Stochastic Macroscopic Modeling Framework to Interpret the Fundamental Diagram
• Airborne Traffic Flow Data and Traffic Management
• Analysis of LWR Model with Fundamental Diagram Subject to Uncertainty
• Bird’s Eye Perspective on Traffic Flow: New Insights from Observing Traffic from a Helicopter
• Calibration of Steady-State Car-Following Models Using Macroscopic Loop Detector Data
• Effect of Lane-Change Maneuvers on a Simplified Car-Following Theory
• Empirical Relation Between Stochastic Capacities and Capacities Obtained from the Speed-Flow Diagram
• From Inductance Loops to Vehicle Trajectories
• Fundamental Diagram for Signalized Arterials: An Empirical Analysis Using High-Resolution Traffic Data
• Fundamental Diagram on Urban Roads: Myth or Truth?
• Greenshields’ Legacy: Highway Traffic
• Greenshields’ Legacy: Urban Streets
• Influence of Various Restrictions on Speed-Flow Models
• Lane-Change Maneuver Detection with Differential Global Positioning System Data from Probe Vehicle
• Measuring Traffic Flow Using Real-Time Data
• Modern Approaches to Basic Traffic Modeling: Three-Phase Traffic Theory
• Quality of Service Beyond the Traditional Fundamental Diagram
• Strategies to Improve Dissipation into Destination Networks Using Macroscopic Network Flow Models
• Traffic Flow Prospectives: From Fundamental Diagram to Energy Balance
• Traffic Flow Theory Historical Research Perspectives
• Treiterer’s Legacy: Traffic Flow Measurements and Characteristics