It has been recently shown that a macroscopic fundamental diagram (MFD) linking space-mean network flow, density and speed exists in the urban transportation networks under some conditions. An MFD is further well defined if the network is homogeneous with links of similar properties. This...

Travel time is an important performance measure for transportation systems, and dissemination of travel time information can help travelers make reliable travel decisions such as route choice or departure time. Since the traffic data collected in real time reflects the past or current conditions...

Transport systems in real cities are complex with many modes of transport sharing and competing for limited road space. This work intends to understand how space distributions for modes and interactions among modes affect network traffic performance. While the connection between performance of...

This dissertation deals with the application of Advanced Traveler Information Systems (ATIS) in incident management. Using an idealized traffic corridor and deterministic queuing methods, conditions under which route guidance information is useful are identified. Benefits to traffic guided with...

In this paper, a fuzzy traffic density homogenizer is proposed to alleviate or avoid congestion by smoothing the traffic density distribution profile over freeway lanes. The proposed fuzzy homogenizer consists of two parts: the fuzzy mean speed controller and the fuzzy on- ramp controller....

This paper presents microscopic time-space diagrams for several shock waves over 100-200m distances. The primary focus of the paper is on presenting the data rather than analysis. The diagrams should be of general interest to researchers studying traffic congestion.

This report evaluates several engine torque control laws for longitudinal vehicle control. The control laws are implemented and tested on a low speed test track. The test results and analysis show that engine manifold air-dynamics can not be neglected especially at low engine speed. An...

Focusing on neighborhood travel, this study first reviews the development of vehicles and roads suited to such travel. It then considers community development trends that might encourage or thwart the adoption and use of such vehicles. Demands for vehicles and travel patterns are then treated,...

Linear and nonlinear multivariate statistical analyses are applied to determine how the types of accidents that occur on heavily used freeways in Southern California are related to both the flow of traffic and weather and ambient lighting conditions. Traffic flow is measured in terms of time...