PATH

Developing Operating Rules and Simulating Performance for One-dedicated-lane Bus Rapid Transit/Light Rail System

Tsao, H.-S Jacob
Dessouky, Yasser
Ingham, Kevin
Ongkowidjojo, Rocky
Tsao, Jason R.
2010

Caltrans has recently funded a project, through the Mineta Transportation Institute (MTI) at San Jose State University, about geometric and performance feasibility of using virtually only one dedicated but dynamically reversible lane to provide two-way Bus Rapid Transit (BRT) or light-rail services at the same or similar service levels as those achievable with two dedicated lanes, along the median of a busy commute corridor with at-grade crossings and regular provision of left-turn lanes. This project extended that deterministic performance study in four complementary directions. We (i)...

Video Vehicle Detector Verification System (V2DVS)

MacCarley, Art
Slonaker, John
2008

A practical need to assess the accuracy and attributes of each of the many types of roadway sensors and detectors motivated the California Department of Transportation to construct a traffic detector test bed on I-405 in Southern California. With up to ten detectors of different types under concurrent test in each of six lanes, a means for automating the testing process became imperative, since traditional human verification methods were not practical.This project involved the development of an automated data acquisition and verification system that utilizes a consensus of the results from...

String Stability Of Interconnected Systems: An Application To Platooning In Automated Highway Systems

Swaroop, D.v.a.h.g
1997

This dissertation investigates various platooning strategies and their impact on the performance of the platoon. Various decentralized control algorithms are designed and their performance is characterized in terms of the minimum attenuation of the maximum spacing errors that can be guaranteed from vehicle to vehicle in the platoon. A direct adaptive control algorithm that guarantees improved performance is also designed.

Factors Influencing Productivity and Operating Cost of Demand Responsive Transit

Palmer, Kurt
Dessouky, Maged
Zhou, Zhiqiang
2008

Since the enactment of the Americans with with Disabilities Act, in 1991, operating expenses for Demand Responsive Transit have more than doubled as demand for this mandated service has expanded. Many advanced technologies and management practices have been proposed and implemented to improve the efficiency of the service; but, evidence for the effectiveness of these actions has been based upon projections or small pilot studies. We present the results of a nationwide study involving 67 large transit agencies. We evaluate the impact of implemented technologies and practices upon...

Development of Integrated Meso/Microscale Traffic Simulation Software for Testing Fault Detection and Handling in AHS

Horowitz, Roberto
2004

In this report, we describe the research carried out under PATH Task Order 4208. The objective of this project was to bridge the gap between the Automated Highway System (AHS) simulators SmartAHS and SmartCAP, by implementing an integrated AHS micro-meso simulation environment for analyzing a large-scale AHS network. In fulfillment of this goal, a meso-microscale traffic simulator was developed that allows a stationary region of microsimulation to be defined within a larger, mesosimulated AHS. This simulator permits analysis of traffic behavior in situations where both vehicle-level (...

Longitudinal Control Of Heavy Duty Vehicles: Experimental Evaluation

Yanakiev, Diana
Eyre, Jennifer
Kanellakopoulos, Ioannis
1998

This report describes the results of experimental evaluation of longitudinal control algorithms for commercial heavy vehicles (CHVs). Given the problem of delays in the fuel and brake actuators of automated CHVs, the researchers present improved modeling of air brakes for CHVs, and novel nonlinear algorithms for the longitudinal control of CHVs without intervehicle communication. The significance of these results in terms of Intelligent Transportation Systems (ITS) deployment is that one of the major obstacles to autonomous vehicle following for CHVs has now been removed The authors also...

Identifying Density-Flow Relations on Arterial Surface Streets

Ahn, Soyoung
Cassidy, Michael J.
2002

A simple car-following rule was verified by studying vehicles discharging from long queues at signalized intersections. These observations indicated that the time-space trajectory of a jth vehicle discharging on a homogeneous intersection approach was essentially the same as the j−1th vehicle except for a translation in space and time. This is in agreement with a simplified theory proposed by G.F. Newell. The finding indicates that the congested branch of a density-flow curve is linear in form.

SmartBRT: A Tool for Simulating, Visualizing, and Evaluating Bus Rapid Transit Systems

VanderWerf, Joel
2005

Evaluation of BRT systems. SmartBRT is for designed for modeling and simulating hypothetical transit systems, especially those making use of Bus Rapid Transit (BRT) technologies and policies. SmartBRT can be used to evaluate new technologies and policies that haven't been fully explored in deployed systems. SmartBRT does not output emissions or cost data. SmartBRT does not calculate the longterm effects of BRT deployment, such as changes in mode choice. To aid in evaluation, SmartBRT provides features for data gathering and statistics. The model report has a complete list of variables that...

A Comparison Of Traffic Models: Part 1, Framework

Lo, Hong K.
Lin, Wei-hua
Lawrence, C.
Chang, Elbert
Tsao, Jacob
1996

This report defines a framework for comparing dynamic traffic models. It emphasizes four dimensions: functionality, traffic dynamics, route choice dy namics, and overall network performance. The first dimension compares the models through a check-list of model functions. Regarding the last three comparison dimensions, a total of five networks and twelve scenarios are defined. These test scenarios are designed to accentuate model properties and differences. Also included in the report are a list of performance measures for comparison purpose, and a discussion of the interpretation of...

A Comparison Of Traffic Models: Part 1, Framework

Lo, Hong K.
Lin, Wei-hua
Liao, Lawrence C.
Chang, Elbert
Tsao, Jacob
1996

This report defines a framework for comparing dynamic traffic models. It emphasizes four dimensions: functionality, traffic dynamics, route choice dy namics, and overall network performance. The first dimension compares the models through a check-list of model functions. Regarding the last three comparison dimensions, a total of five networks and twelve scenarios are defined. These test scenarios are designed to accentuate model properties and differences. Also included in the report are a list of performance measures for comparison purpose, and a discussion of the interpretation of...