PATH

Revenue Models for Advanced Traveler Information Systems

Yim, Y. B.
2001

The paper describes current trends in the traveler information supply system and the prospect for potential markets for advanced traveler information in the United States and Europe. Alternative revenue models are identified that may be able to support the operation of the newly created traveler information centers in the post-field operational test phase. In the past, public agencies have been reluctant to share traffic management responsibilities with the private sector. However, this study found that the current trend is toward a public-private partnership in the form of a franchised or...

The Aerodynamic Forces On Misaligned Platoons

Marcu, Bogdan
Browand, Fred
1998

This report summarizes wind tunnel experimental measurementson the aerodynamic interaction between members of misaligned platoons. Experiments are conducted at the University of Southern California's Dryden Wind Tunnel Facility. All experiments are made using 1/8 scale models of 1991 Chevy Lumina minivan. Models are placed above a ground plane with a porous surface, through which slight suction is applied to remove the boundary layer. Refurbishing of the ground plane surface, and its repositioning to a 1 degree angle of attack produce significantly improved air flow through the test...

Section-Related Measures of Traffic System Performance: Prototype Field Implementation

Ritchie, Stephen G.
Sun, Carlos
Oh, Seri
Oh, Cheol
2001

In this project (MOU 336),an initial phase of a field implementation was accomplished of the results of a previous research project (MOU 224),in which a vehicle reidentification algorithm based on loop signature analysis was developed using freeway traffic data.This algorithm was extended to non-freeway cases, initially using a section of 2-lane major arterial in cooperation with the City of Irvine,California.The technique was enhanced to address problems such as "irregularities " in vehicle signatures associated with trucks,tail-gating vehicles and erroneous counting of vehicles,with the...

Dynamic Origin/Destination Estimation Using True Section Densities

Sun, Carlos
Porwal, Himanshu
2000

This final report presents a practical approach for dynamic origin/destination demandestimation. The proposed dynamic origin/destination estimation framework addressesmany of the shortcomings of the existing formulations and presents a formulation forgeneral networks and not just corridors. One unique feature of this framework is its useof section density as a variable instead of flow. The framework is built upon thefoundation of static origin/destination matrix estimation by adding the temporal aspect.Two traffic assignment models, namely DYNASMART and DTA are used for assigningdynamic...

Longitudinal Control Of A Platoon Of Vehicles. III, Nonlinear Model

Sheikholeslam, Shahab
Desoer, Charles A.
1990

This paper presents a systematic analysis of a longitudinal control law for a platoon of non-identical vehicles using a non-linear model for the vehicle dynamics.

Highway Electrification And Automation Technologies - Regional Impacts Analysis Project: Executive Summary

Scag
Path
1993

The Highway Electrification and Automation Technologies Regional Impacts Analysis Project (HE&A) addressed the transportation-related problems of freeway congestion, air pollution, and dependence on fossil fuels in southern California. The impacts of roadway electrification and highway automation were investigated to determine to what extent these advanced technologies could alleviate these problems. For the highway electrification technology, utility, environmental, and economic impacts were also studied. The feasibility of implementing one or more demonstrations in the six-county...

Some Theoretical Aspects Of The Benefits Of En-route Vehicle Guidance (ervg)

Al-Deek, Haitham M.
Kanafani, Adib K.
1989

This paper concerns the benefits from vehicle route guidance in urban networks. We suppose that vehicle routes can be altered by En-Route Vehicle Guidance (ERVG) in such a way as to achieve system optimal assignment. Benefits are measured by the savings in total travel time for a given demand when comparing this assignment with the user equilibrium, which is assumed to occur in the absence of route guidance. A continuum approach is used to analyze some idealized corridors in which a freeway is superimposed over a dense grid of surface streets. Two cases are considered: in the first, the...

Enhanced AHS Safety Through the Integration of Vehicle Control and Communication

Hedrick, J. K.
Uchanski, M.
Xu, Q.
2003

In fiscal year 2002/2003 we finished the study of the effect of vehicle-vehicle/vehicle-roadside communication on the performance of adaptive cruise control (ACC) systems. Two simulation studies were finished. The first is a single ACC vehicle simulation using MATLAB/SIMULINK. A cut-in scenario and a braking scenario are tested. Communication greatly saves control effort in the former scenario, while it has little effect in the latter. The other work simulates ACC controlled highway merging using SHIFT language. The results show the beneficial effects of communication in terms of the...

Caltrans Connected and Automated Vehicle Strategic Plan

McKeever, Ben
Wang, Peggy
West, Tom
2020

This report is the culmination of a year-long effort to develop a connected and automated vehicle (CAV) Strategic Plan for the California Department of Transportation (Caltrans). The purpose of the CAV Strategic Plan project is to define a vision and tactical strategy for Caltrans in preparation for CAV deployment in California and to begin a policy development process to keep California at the forefront of this emerging industry. This plan recommends actions for Caltrans to carry out within the next five years. Caltrans has a strong interest in planning for the fast-moving evolution in...

The Cell Transmission Model. Part I: A Simple Dynamic Representation Of Highway Traffic

Daganzo, Carlos
1993

This paper presents a simple representation of traffic on a highway with a single entrance and exit. The representation can be used to predict traffic's evolution over time and space, including transient phenomena such as the building, propagation and dissipation of queues. The easy-to-solve difference equations used to predict traffic's evolution are shown to be the discrete analog of the differential equations arising from a special case of the hydrodynamic model of traffic flow. The proposed method automatically generates appropriate changes in density at locations where the...