Data

Distributed Surveillance and Control on Freeways

Coifman, Benjamin
2004

Efficient management of a road network requires continuous decision-making based on conditions on the network and an understanding of the impacts of the decisions made. These conditions are usually measured with fixed-point surveillance systems, most of which are deployed in such a manner as to require communication links that are always connected and are polled at regular intervals. All of the sensor data are typically sent to a Traffic Management Center (TMC) for assessment, yet most of the time no action is taken in response to the data, leading to unnecessarily high communication costs...

Effectiveness of VMS Using Empirical Loop Detector Data

Huo, Hong
Levinson, David
2006

This study employs traffic data and incident data from the Twin Cities of Minneapolis and St. Paul, Minnesota. The conclusion in this study provides guidance on making policy about investing in VMS systems.Few studies utilize empirical traffic data. They either use costly surveys or conduct traffic simulation, which are expensive and may not conform well to reality. This study uses empirical traffic flow and occupancy data on both mainline and ramps, collected every 30 seconds to estimate the effectiveness of VMS. The variation of diversion rate before and after warning messages is...

Augmented Speed Enforcement Project at UC Berkeley - Executive Summary

Chan, Ching-Yao
Gupta, Somak Datta
2015

In this project, a speed alert and augmented enforcement system (aSE) was developed with a combination of sensing, image processing and recognition, wireless communication. The system includes a speed camera that captures speeding vehicles, and a changeable message sign that displays speeder’s license plate number and measured speed, and a web page that allows police officers to monitor the incidence of violators traveling at excessive speeds. The aSE system was field tested for a work zone application on a rural highway. With data collected over multiple weeks, under a baseline scenario...

Virtual Weigh Stations in California: A Preliminary Cost-Effectiveness Analysis

Santero, Nicholas
Nokes, William
Harvey, John
2005

A new technology known as Virtual Weigh Stations (VWS) is intended to transform data-collecting weigh-in-motion (WIM) sites to weight enforcement mechanisms. This study investigates the possible benefits to the highway pavements in California from potential use of VWS. The investigation proceeded in two steps: (1) determining the damage currently caused by overweight trucks and (2) modeling the potential pavement life saved with VWS. The data used for analysis is from the California Department of Transportation (Caltrans) WIM database.

Evaluation of ITS Technology for Bus Transit Systems

Hall, Randolph
Dessouky, Maged
Zhang, Lei
Singh, Ajay
Patel, Vishal
1999

Recently, bus transit service providers have begun to adopt Intelligent Transportation Systems (ITS) technologies such as Global Positioning Systems (GPS) and Mobile Data Terminals. These systems taken together have the potential to reduce the cost of providing transportation services through the execution of real-time control strategies, performance monitoring systems and data collection to support service realignment. We evaluate bus control strategies using ITS against those without ITS. Two levels of ITS are considered: (1) system with centralized tracking and (2) system with...

Implementation of a Tool for Measuring ITS Impacts on Freeway Safety Performance

Golob, Thomas F.
Marca, James
Recker, Will
2007

The research was undertaken to develop a tool for assessing the impacts of changes in freeway traffic flow on the level of traffic safety. Safety is measured in terms of the probability of a reportable accident, and the tool is so far restricted to urban freeway mainlines with substantial traffic levels. The tool will: (1) monitor the safety level of freeway operations (2) aid in freeway planning. The tool was calibrated by applying advanced statistical models to actual data combined from two sources: Vehicle Detector Station (VDS) data for freeways in Orange County (District 12), and data...

Survey on Status of Knowledge and Interest of Smartcard Fare Collection Systems Among US Transit Agencies

Iseki, Hiroyuki
Yoh, Allison C.
Taylor, Brian D.
2006

This study analyzes data collected from an on-line survey of U.S. transit agencies to (1) gauge current levels of interest in smart card technologies, (2) document the current status of smart card system adoption among transit agencies, the degree of planning and implementation, and levels of participation in interagency collaborations, and (3) examine factors common to agencies that have adopted smart card technology and those that have not.Reflecting significant diversity in their goals and objectives, operating environments, financial conditions, and clients served, transit agencies...

A Statewide Optimal Resource Allocation Tool Using Geographic Information Systems, Spatial Analysis, and Regression Methods

Goulias, Konstadinos G.
Golob, Thomas F.
Yoon, Seo Youn
2008

The overall objective of this project is to develop an optimal resource allocation tool for the entire state of California using Geographic Information Systems and widely available data sources. As this tool evolves it will be used to make investment decisions in transportation infrastructure while accounting for their spatial and social distribution of impacts. Tools of this type do not exist due to lack of suitable planning support tools, lack of efforts in assembling data and information from a variety of sources, and lack of coordination in assembling the data. Suitable planning...

PEDAMACS: Power Efficient and Delay Aware Medium Access Protocol for Sensor Networks

Coleri, Sinem
Varaiya, Pravin
2004

We consider a class of sensor networks with two special characteristics. First, the nodes periodically generate data for transfer to a distinguished node called the access point. Second, the nodes are (transmit) power and energy limited, but the access point, which communicates with the ‘outside world’, is not so limited. Such networks might be used for instance when a geographically distributed physical process, such as traffic on a freeway or at an urban street intersection, is periodically sensed for purposes of process control. We propose a medium access control scheme, called PEDAMACS...

Modeling And Control Design For A Computer Controlled Brake System

Raza, H.
Xu, Z.
Ioannou, P.
Yang, B.
1995

In this paper, the problem of modeling and control design of a computer controlled brake system is addressed. A nonlinear model for the brake system is developed by analyzing the input-output data obtained from the test bench. A controller for the brake system is designed by applying feedback linearization techniques along with intuitive modifications to meet the closed loop specifications.