PATH

Investigation Of An Optical Method To Determine The Presence Of Ice On Road Surfaces

Misener, James
1998

This report presents a review of alternative techniques to determine the presence of ice on road surfaces. It examines techniques ranging from passive, in-pavement technologies, to different remote sensing techniques. The author presents the Polarized Reflectance Infrared Signature Method (PRISM) technique which uses differences in measured near infrared reflectance between ice, water and dry road due to absorption, in addition to the effect of polarization to discount the contribution of specutacular reflectance off the front surface.

Field Deployment and Operational Test of an Agent-based, Multi-Jurisdictional Traffic Management System

Rindt, Craig R.
McNally, Michael G.
2007

This report describes a reinterpretation of how the philosophy underlying the Cartesiusmulti-jurisdictional incident management prototype can be used as an organizing princi-ple for real-world multi-jurisdictional systems. This interpretation focuses on the power ofthe Distributed Problem Solving (DPS) approach Cartesius uses to partition analysis andoptimization functions in the system across jurisdictions. This partitioning minimizes theamount of local information that must be shared between jurisdictions and paves the way fordefining a collection of TMC-to-TMC messages that support the...

Implementing A Dynamic O-D Estimation Algorithm within the Microscopic Traffic Simulator Paramics

Garcia, Reinaldo C.
2002

California has long recognized the potential for applying electronic and other transportation systems technologies to address the significant mobility and economic challenges in the state,and the rest of the nation.Through an aggressive Advanced Transportation Systems Program,Intelligent Transportation Systems (ITS)are being researched,built,and tested for deployment.These ITS will address today s transportation needs and those of the twenty-first century.An important element of this program is the California Advanced Transportation Management Systems Testbed (California ATMS Testbed)...

The Spatial Evolution of Traffic Under the Two Wave Speed Assumption: A Shortcut Procedure and Some Observations

Daganzo, Carlos F.
1993

This paper describes the behavior of traffic in a homogeneous highway according to the hydrodynamic theory, in the special casewhere the flow-density relationship is triangular; i.e. when only two wave velocities exist. It presents an exact formula thatpredicts the vehicle that would be found at position x at time t, given the locations of all the vehicles at time zero. The formula, which does not require identification of the vehicle positions at intermediate times, automatically accounts for the creation and dissipation of any shocks. It can be used to calculate system performance...

DYN-OPT Users Manual

Caliskan, C.
Hall, R.W.
1997

This document is a users manual for DYN-OPT, a linear program that optimally and dynamically assigns traffic to lanes on an automated highway. The program maximizes the total flow across the highway over a pre-specified length of time. DYN-OPT solves a path-based formulation in which the highway is represented by discrete segments, time is divided into periods and traffic between origins and destinations follows a user- specified distribution.

Event-based ATIS: Practical Implementation and Evaluation of Optimized Strategies (Part I)

Jayakrishnan, R.
Tsai, Wei K.
Oh, Jun-Seok
Adler, Jeffrey
1999

This project will further adapt and enhance the previous research of relevance to event-based Advanced Traveler Information Systems (ATIS) and implement the algorithms for traffic management in Anaheim. The implementation involves the Caltrans-UCI ATMS research testbed framework at the UCI Institute of Transportation Studies, as well as the physical hardware available for communication to the city of Anaheim. The analytical algorithms proposed for use here include those for static and dynamic traffic assignment. and the modeling schemes used are the result of previous PATH and Testbed...

The Aerodynamic Performance Of Platoons: A Final Report

Zabat, Michael
Stabile, Nick
Farascaroli, Stefano
Browand, Frederick
1995

This report details the aerodynamic performance of individual members of 2, 3, and 4-vehicle platoons. The primary purpose of the tests described is to quantify the behavior of vehicle drag as a function of vehicle spacing.

Optimized Vehicle Control/Communication Interaction in an Automated Highway System

Hedrick, J. K.
Chen, Y.
Mahal, S.
2001

One of the main goals of an Automated Highway System environment is to increase the throughput of vehicles traveling on the highway. By moving vehicles in a platoon (a group of tightly spaced vehicles), the traffic flow capacity can be greatly increased. The control law developed for vehicles to safely travel in a platoon is dependent on the lead and preceding vehicle's velocity and acceleration profiles. This information guarantees string stability (i.e. spacing errors between vehicles do not increase down the chain of vehicles). These profiles are transmitted to the vehicle via wireless...

Integration Of Probe Vehicle And Induction Loop Data: Estimation Of Travel Times And Automatic Incident Detection

Westerman, Marcel
Litjens, Remco
Linnartz, Jean-Paul
1996

This research investigates methodologies for fusing and further processing real-time road traffic data collected by probe vehicles and induction loop detectors in order to obtain relevant traffic information that is essential for effective deployment of Advanced Traffic Management Information Systems (ATMIS). Methods for estimating travel times and performing automatic incident detection for ATMIS based on induction loop or probe vehicle data are developed. By properly incorporating additional traffic data from the other source the performance of the developed methods is shown to improve...

Highway Electrification And Automation Technologies - Regional Impacts Analysis Project: Phase II: Scenario For Advanced Highway Technologies

Scag
Partners for Advanced Transportation Technology (PATH)
1993

This report completes the second phase of the Highway Electrification and Automation Technologies Regional Impacts Analysis Project, a three-year investigation of the potential regional mobility and air quality benefits that could result from implementation of advanced highway technologies in the greater Los Angeles area. This Phase II report focuses on development of a modelling framework for evaluation of the impacts of the alternative advanced technologies applied to selected freeway lanes. The advanced technology system scenarios were chosen from several alternatives based on...