ITS Berkeley

CALSIG an Analysis and Design Procedure for Signalized Intersections

Cassidy, M. J.
May, A. D.
1988

Research Problem for the 1985 Highway Capacity Manual

Cassidy, M. J.
May, A. D.
1988

The 1985 Highway Capacity Manual: Supplemental Report for California Conditions

Cassidy, M. J.
May, A. D.
1988

CALSIG Software User's Manual

Sanchez, I.
Cassidy, M. J.
May, A. D.
1988

A Proposed Analytical Technique for the Design and Analysis of Major Freeway Weaving Sections

Cassidy, Michael James
1990

Weaving occurs when merging traffic streams entering a freeway from an on-ramp cross over diverging traffic streams exiting the freeway via a nearby off-ramp. The intense lane-changing activity which typically occurs in weaving areas can create significant operational problems. Thus, weaving sections often represent bottleneck locations in urban freeway systems. The prevalence of weaving areas on U.S. freeways warrants the need for analytical techniques which can reliably analyze and/or design these critical freeway components. However, previous research at the Institute of Transportation...

Proposed Analytical Technique for Estimating Capacity and Level of Service of Major Freeway Weaving Sections

Cassidy, Michael J.
May, Adolf D.
1991

Weaving typically occurs where merging traffic movements cross over diverging movements. The prevalence of weaving areas on freeways warrants the need for analytical techniques that can reliably analyze or design these critical freeway components. However, previous research at the University of California suggested that existing analytical procedures may not predict weaving operation with a sufficient degree of reliability. Consequently, a more reliable procedure for evaluating weaving performance was developed. Unlike most existing procedures, the proposed technique evaluates...

An Application of Advanced Technologies for Freeway Traffic Management: An Indiana Case Study

Cassidy, Michael J.
Sinha, Kumares C.
1991

This paper presents a summary of technologies being proposed for an electronic surveillance and control system on the Borman Expressway in Indiana. The system would consist of three elements: 1) Traffic surveillance; 2) Motorist information; and, 3) Congestion management.

Evaluating the Capacity of Freeway Weaving Sections

Wang, Mu-han
Cassidy, Michael J.
Chan, Patrick
May, Adolf D.
1993

The research described in this paper employed simulation modeling and empirical observations in an effort to: (1) Identify the traffic flow phenomena that characterize freeway weaving section capacity; and (2) determine appropriate traffic flow rate values that reflect weaving section capacity. The INTRAS microscopic simulation model was calibrated and validated using empirical data collected at a weaving site. Increasing traffic demands were then sequentially input into repeated simulation runs to identify the boundary between uncongested and congested operation. Where a weaving...

Application of Fuzzy Logic and Neural Networks to Automatically Detect Freeway Traffic Incidents

Hsiao, Chien-Hua
Lin, Ching-Teng
Cassidy, Michael
1994

To date, efforts to manage freeway congestion have been seriously impeded by the inability to promptly and reliably detect the presence of traffic incidents. Traditional incident‐detection algorithms distinguish between congested and uncongested operation by comparing measured traffic‐stream parameters with predefined threshold values. Given the range of possible operating conditions in the traffic stream, selecting a single threshold value, and the suitability of that selected threshold, is full of uncertainty. This inherent uncertainty makes fuzzy logic a promising approach to...

An Electronic Surveillance and Control System for Traffic Management on the Borman Expressway. Part II, Calibrating a Simulation Model

Wang, Mu-Han
Cassidy, Michael J.
1995

This report presents a project whose purpose was to calibrate a freeway simulation model to emulate traffic operating conditions on the Borman Expressway. The computer simulation model can then be used to predict impacts created by a host of possible conditions including incident occurrences, maintenance, reconstruction and the deployment of various freeway control and management strategies. The results of the simulation model can be used as a decision-making tool for adopting suitable policies to address operating needs.