PATH

Light Rail System Safety Improvements Using ITS Technologies

Chira-chavala, Ted
Coifman, Ben
Empey, Dan
Hansen, Mark
Lechner, Ed
Porter, Chris
1997

This report describes research which studied identifying and analyzing the effectiveness of countermeasures designed to reduce light rail crashes. Focus is in collisions with road vehicles at intersections. The light rail system for the Santa Clara County Transportation Agency in California served as the focus of the study.

University of California, Davis Long-Range Development Plan: A Davis Smart Mobility Model

Shaheen, Susan
Rodier, Caroline J.
Finson, Rachel S.
2003

The goal of the Smart Mobility Model project was to optimize individual mobility options through improved connectivity among modes, enhanced techniques to link landuse planning and transportation system design, advanced information technologies, and clean-fuel vehicles. The California PATH/Caltrans partnership with the University of California, Davis (UC Davis) was initiated after campus planners expressed interest in learning how innovative mobility services and technologies (such as carsharing and smart parking management) might help to alleviate the transportation impacts of a campus...

Developing Calibration Tools for Microscopic Traffic Simulation Final Report Part III: Global Calibration - O-D Estimation, Traffic Signal Enhancements and a Case Study

Zhang, Michael
Ma, Jingtao
Singh, Shailendra P.
Chu, Lianyu
2008

The central goal of this research is to develop a systematic framework and the support tools to ease, streamline and speed up the calibration of micro simulation projects. Part III of the final report documents the accomplishments achieved in the second phase of the research project. They include the following.First, to overcome the lengthy time it takes for GA to obtain local and global driving behavior modeling parameters, we implemented a faster heuristic optimization technique, the simultaneous perturbation stochastic approximation (SPSA) and compared its performance with other...

Literature Review Report on Benefit/Cost Studies and Evaluations of Transit Management Systems

Jia, Xudong
Sullivan, Edward
Nuworsoo, Cornelius
Hockaday, Neil
2008

This study addresses the benefits and costs of Advanced Public Transportation Systems (APTS) applications in small and medium sized transit agencies using the research test implementation of a small transit oriented Intelligent Transportation System (ITS) on San Luis Obispo Transit as a case study. The Smart Transit System at San Luis Obispo is in a pre-commercialized state and implements the Efficient Development of Advanced Public Transportation Systems (EDAPTS) framework concept (Gerfen, 2001). The system has many potential benefits that will be identified and evaluated from a cost of...

New Approach to Bottleneck Capacity Analysis: Second Interim Report, Work Accomplished During Fiscal Year 2004-2005

Banks, James
2006

This report documents work accomplished during Fiscal Year 2005-2005 as a part of a research project entitled “New Approach to Bottleneck Capacity.” This project is developing an alternative to the traditional Highway Capacity Manual approach to capacity analysis in which capacity flow [either pre-queue flow (PQF) or queue discharge flow (QDF)] is related to a set of intervening variables, including the average time gaps in the critical lane (i. e., that with the highest flow rate) and the distribution of flow across the lanes, represented by the critical lane flow ratio (i. e., the flow...

Regulation Layer Software Integration

Deshpande, Akash R.
1999

The project reuses the sensor and actuator interface software developed by California PATH for the DEN1097 automated highway system demonstration on Highway I17 in San Diego during August 1997. This software is provided on the QNX operating system. It interfaces with the magnetometers, radars, and the various intenal sensors such as wheel speed, engine speed, steering angle, etc, as well as with the actuators such as throttle, brake, and steering. In this project, we wrote an interface process that communicates between the driver process described above and the controller process described...

Collision Avoidance Analysis for Lane Changing and Merging

Jula, Hossein
Kosmatopoulos, Elias B.
Ioannou, Petros A.
1999

One of the riskiest maneuvers that a driver has to perform in a conventional highway system is tomerge into the traffic and/or to perform a lane changing maneuver. Lane changing/mergingcollisions are responsible for one-tenth of all crash-caused traffic delays often resulting incongestion. Traffic delays and congestion, in general, increases travel time and has a negativeeconomic impact.In this paper, we analyze the kinematics of the vehicles involved in a lane changing/mergingmaneuver, and study the conditions under which lane changing/merging crashes can be avoided.That is, given a...

Potential Erroneous Degradation of High Occupancy Vehicle (HOV) Facilities

Fournier, Nicholas, PhD
Farid, Yashar Zeinali, PhD
Patire, Anthony David, PhD
2021

This document is the final report for Task ID 3710 (65A0759), a project titled “Potential Erroneous Degradation of High Occupancy Vehicle (HOV) Facilities”. This report contains a compilation of three previous technical memorandums titled “Survey of Data-Mining Methods”, “Performance of Methods”, and “Magnitude of HOV Degradation”. HOV lane sensors in Caltrans’ Performance Management System (PeMS), are sometimes misconfigured as general-purpose lanes. In this situation, HOV lane data is mistakenly aggregated with general-purpose lane data and vice versa. The purpose of this project was to...

Quantifying the Performance of Countermeasures for Collision Concentration Related to Ramp/Freeway Mainline Junctions

Lee, Joon ho, PhD
Chan, Ching-Yao, PhD
Ragland, David R., PhD
2009

This study performed before-and-after analyses (comparisons of collisions before and after the construction of auxiliary lanes) on collision rate at nine study sites in California in order to achieve two objectives: (i) to estimate the freeway Crash/Collision Reduction Factor (CRF) for auxiliary lanes, and (ii) to develop design guidelines for the construction of auxiliary lanes. Findings indicate that on average, collision rates decreased by 17.3 percent at nine study sites. The study also found that after construction of auxiliary lanes at two study sites, collision rates increased when...

A Review of the Optimized Policies for Adaptive Control Strategy (OPAC)

Liao, Lawrence C.
1998

Optimized Policies for Adaptive Control (OPAC) is a real-time demand-responsive traffic signal timing optimization algorithm for individual intersections. It was developed at University of Lowell under the sponsorship of U.S. Department of Transportation in the early 80s. OPAC distinguishes itself from traditional cycle-split signal control strategies by dropping the concept of cycle. In OPAC, the signal control problem consists of a sequence of switching decisions made at fixed time intervals. At each decision point the question is whether to extend or terminate current phase. Dynamic...