Modeling

Identification And Prioritization Of Environmentally Beneficial Intelligent Transportation Technologies

Shaheen, S.
Young, T.
Sperling, D.
Jordan, D.
Horan, T.
1998

This report presents an literature review on the energy and environmental impacts of Intelligent Transportation Systems (ITS) technologies, a presentation of the development of deployment/modeling scenarios, and a description of the modeling effort. It looks at the current polity context and regulatory arena in which ITS technologies will be deployed. It also provides scenarios and market penetration estimates developed to form the basis of modeling efforts with the INTEGRATION model.

Simulation Modeling Of The Santa Monica Freeway

Bloomberg, Loren D.
May, Adolf D.
1994

As part of a project investigating the benefits of Intelligent Vehicle Highway Systems (IVHS) technology using simulation, two models of the Santa Monica Freeway in Los Angeles were developed. This report describes the work performed to create, test, and apply these simulations. Two independent simulations were coded, using FREQ and INTEGRATION models, from the available data. The report describes the strategies, limitations, and assumptions needed to code the Santa Monica Freeway using the two simulation tools. After coding the models, calibrating the output to match traffic performance...

Dynamic Modeling Of Tractor-semitrailer Vehicles In Automated Highway Systems

Chen, Chieh
Tomizuka, Masayoshi
1995

This report is concerned with the dynamic modeling of the tractor- semitrailer vehicles in Automated Highway Systems (AHS). The objectives of the research are to characterize the dynamic response of articulated heavy-duty vehicles, identify the key system parameters, develop control algorithms to achieve automatic guidance, and conduct experiments on lateral guidance control of articulated heavy-duty vehicles. A modeling approach for roll, pitch and yaw motions of tractor-semitrailer vehicles is described.

Transit ITS Simulator (TRANSITS): Design Document

Dessouky, Maged
Singh, Ajay
Hall, Randolph
1997

This report describes a simulation model developed to evaluate the impact of using Intelligent Transportation Systems (ITS), such as Global Positioning Systems (GPS) for bus tracking, on controlling buses in wide-area transit networks. Control strategies with ITS will be compared against those without ITS (i.e., they do not rely on communication or tracking). The model is developed using a general-purpose simulation language, AweSim (Pritsker, 1997). The simulation model is generic and independent of any dedicated transit network. The model has high flexibility and can be used to simulate...

Validation of the Incremental Transfer Model

Robert, Tim
Lin, Wei-Hua
Cassidy, Michael
1999

This report documents our validation effort on the Incremental Transfer (IT) model, which is a macroscopic traffic flow model capable of handling freeway systems with special lanes and priority vehicles. The validation study is performed with field data from a 1.7-mile long freeway segment with a congested off-ramp in Oakland, California. In our study, vehicles exiting the off- ramp of this segment are treated as "regular vehicles" and through vehicles as "special vehicles." By assuming that the exiting or "regular" vehicles must stay on the "near" side lanes, we examine the spatial...

Ideal Dynamic User-Optimal Route Choice: A Link-Based Variational Inequality Formulation

Ran, Bin
Boyce, David E.
1995

The ideal dynamic user-optimal (DUO) route choice problem is to determine vehicle flows on each link at each instant of time resulting from drivers using actual minimal-time routes. Actual route time is the travel time incurred while driving along the route. In a previous paper, we presented a route-based optimal control model for the ideal DUO route choice problem. However, this model is not appropriate for largescale transportation networks because some degree of route enumeration is necessary to solve the model. In this paper, we first present the traffic network constraints and link-...

Freeway Performance Measurement System: Final Report

Varaiya, Pravin
2001

PeMS is a freeway performance measurement system for all of California. It processes 2GB/day of 30-second loop detector data in real time to produce useful information. Managers at any time can have a uniform and comprehensive assessment of freeway performance. Traffic engineers can base their operational decisions on knowledge of the current state of the freeway network. Planners can determine whether congestion bottlenecks can be alleviated by improving operations or by minor capital improvements. Travelers can obtain the current shortest route and travel time estimates. Researchers can...

Modeling of the Brake Line Pressure to Tire Brake Force Subsystem

Xu, Z.
Ioannou, P.
1994

One of the most challenging problems in automated vehicle control is when and how to apply the brakes. In order to deal with such a problem, a good understanding of the dynamical behavior of the braking mechanism is essential. In this report we use experimental data from a series of tests performed in collaboration with Ford research engineers to modelthe brake line pressure to tire brake force subsystem. This model will be used together with that of the master cylinder to line pressure currently under study, for developing an overall model for the braking mechanism. The brake model will...

Path ATMIS/Systems State of the Research: Annual Report Fiscal Year 1997/1998

Tam, Robert
1998

This report presents a summary of California PATH Advanced Traffic Management and Traffic Information Systems (ATMIS) and Systems research for FY 1997-1998. For each project, a brief description is given of the objectives, status outline, and principal results. The report is organized into the following research topics: Surveillance Systems, Traffic Management Systems, Traffic Modeling, Traveler Information Systems, Public Transportation Systems, and System Integration and Benefit/Cost Analysis.

TravInfo Evaluation: Traveler Response Element Willingness to Pay for Traveler Information: Analysis of Wave 2 Broad Area Survey

Wolinetz, Louis
Khattak, Asad J.
Yim, Youngbin
2001

TravInfo is a Field Operational Test (FOT) sponsored by the Federal Highway Administration (FHWA) and California Department of Transportation. It aimed to develop a multi-modal traveler information system for the San Francisco Bay Area, combining public and private sector talents. The Broad Area Study is part of the TravInfo FOT evaluation. This paper addresses issues on the willingness to pay for traveler information. Two waves of telephone surveys of Bay Area households were conducted, one prior to and one after the Field Operational Test. The initial survey was conducted in November...