Traffic Operations and Management

The Cell Transmission Model: A Dynamic Representation of Highway Traffic Consistent with the Hydrodynamic Theory

Daganzo, Carlos F.
1994

This paper presents a simple representation of traffic on a highway with a single entrance and exit. The representation can be used to predict traffic's evolution over time and space, including transient phenomena such as the building, propagation, and dissipation of queues. The easy-to-solve difference equations used to predict traffic's evolution are shown to be the discrete analog of the differential equations arising from a special case of the hydrodynamic model of traffic flow. The proposed method automatically generates appropriate changes in density at locations where the...

A Continuum Theory of Traffic Dynamics for Freeways with Special Lanes

Daganzo, Carlos F.
1995

This paper presents a generalized theory of kinematic waves for freeways with two vehicle types and a set of lanes reserved for one of the vehicle classes. The theory is not restricted to freeways on which the special lanes are clearly identified by signs and pavement markings; e.g. for high occupancy vehicles. It may also apply if the restrictions are self-imposed, such as would occur on a freeway segment upstream of a busy off-ramp where the existing traffic naturally avoids the ‘far-side’ lanes. Of particular interest are oversaturated time periods because the original theory of...

An Informal Introduction to Transportation and Traffic Operations

Daganzo, Carlos F.
1995

The Nature of Freeway Gridlock and How to Prevent it

Daganzo, Carlos F.
1995

Steady State Conditions on Automated Highways

del Castillo, Jose M.
Lovell, David J.
Daganzo, Carlos F.
1995

This paper is concerned with technical investigations of traffic operations on automated highways. Estimates are made of the steady-state capacity of such freeways, paying particular attention to the effect of entry and exit maneuvers. The possibility of scheduling departing vehicles appropriately into platoons to minimize extraneous maneuvers is investigated. Characteristics of urban areas likely to be candidates for automated freeways are discussed, and some shortcomings of automated freeways, vis-à-vis conventional freeways, are pointed out. Finally, some areas of future research needs...

Dymanic Traffic Assignment With Queues For ATIS : Final Report For Project MOU 90

Daganzo, Carlos F.
1996

This document reports on a project whose overall objective was to develop a traffic flow model capable of predicting the evolution of multicommodity (multiple destination) network traffic flows consistent with the hydrodynamic theory of traffic flow. The output of this research should enhance the realism of modeling capabilities in representing traffic flows and especially physical queues. This should provide a solid platform for the evaluation of Intelligent Transportation Systems (ITS) improvements, environmental impacts, and dynamic control strategies. In particular, it holds...

Effects of Queue Spillovers in Transportation Networks with a Route Choice

Daganzo, Carlos F.
1996

Determining the Spatial and Temporal Extents of a Queue Upstream of a Bottleneck

Daganzo, Carlos F.
Lovell, David J.
Lawson, Timothy
1996

A simple approach is presented for modifying an input-output (or queueing) diagram to measure the time and distance spent by vehicles in a queue. The fundamental diagram and input-output diagrams are described. The extent of queues in time and space also is described.

Using Input-Output Diagram To Determine Spatial and Temporal Extents of a Queue Upstream of a Bottleneck

Lawson, Tim W.
Lovell, David J.
Daganzo, Carlos F.
1997

A simple approach is described for modifying an input-output (or queue-ing) diagram to measure the time and distance spent by vehicles in a queue in a much simpler and self-serving manner than a time-space diagram. The graphic technique requires construction of a curve depicting the cumulative number of vehicles to have reached the back of the queue as a function of time, but, as indicated here, the technique can be easily automated with a spreadsheet. The technique is applied to the simple case of a constant departure rate from a bottleneck and to the slightly more general case of a...

A Continuum Theory of Traffic Dynamics for Freeways with Special Lanes

Daganzo, Carlos F.
1997

This paper presents a generalized theory of kinematic waves for freeways with two vehicle types and a set of lanes reserved for one of the vehicle classes. The theory is not restricted to freeways on which the special lanes are clearly identified by signs and pavement markings; e.g. for high occupancy vehicles. It may also apply if the restrictions are self-imposed, such as would occur on a freeway segment upstream of a busy off-ramp where the existing traffic naturally avoids the ‘far-side’ lanes. Of particular interest are oversaturated time periods because the original theory of...