PATH

Impacts of Computer-Mediated Communication on Travel and Communication Patterns: The Davis Community Network Study

Balepur, Prashant Narayan
1998

This report examines the interactions among different forms of communication, where travel is also considered a form of communication. Data for this study comes from 148 respondents to the "Activity Diary" survey instrument of the Davis Community Network (DCN) project, which obtained information on 636 uses of DCN. Generation, elimination and modification were considered to be the three major potential results of the present DCN communication and the five major types of communication considered were: in-person, physical object, electronic, in-person with travel, and physical object with...

TMDD Standards Update Recommendations – Data and System Security

Peterson, Brian
2022

This document provides recommendations for modifications to the current TMDD standard. Its goal is to provide a foundation for modernizing the standard. This document specifically provides recommendations for implementing this project’s gap analysis recommendations related to providing security guidance for each approved transmission protocol. Included in this document are recommendations related to a new volume of the specification dealing with minimum security requirements and security recommendations for each data transmission protocol.

On the Numerical Treatment of Moving Bottlenecks

Daganzo, Carlos
Laval, Jorge A.
2003

This report is part of PATH Task Order 4141 and shows how moving obstructions can be modeled numerically with kinematic wave theory. It shows that if a moving obstruction is replaced by a sequence of fixed obstructions at nearby locations with the same "capacity", then the error in vehicle number converges uniformly to zero as the maximum separation between the moving and fixed bottlenecks is reduced. This result implies that average flows, densities, accumulations and delays can be predicted as accurately as desired with this method. Thus, any convergent finite difference scheme can now...

A Time Headway Autonomous Intelligent Cruise Controller: Design and Simulation

Ioannou, P.A.
Ahmed-Zaid, F.
Wuh, D.H.
1994

Autonomous Intelligent Cruise Control (AICC) design is an important part of Advanced Vehicle Control Systems (AVCS). In this report, we design an AICC scheme for vehicle following with constant time headway spacing. The scheme maintains a steadystate inter-vehicle spacing decided by a desired time headway set by the driver. The longitudinal model of the Lincoln Town Car is used for simulations and testing. The vehicle is assumed to be equipped with a relative distance and speed measuring sensor,as well as an absolute speed measuring device.

Automated Highway Systems Operating Strategies and Events: A Driver’s Perspective

Tsao, H.-S. Jacob
Hall, Randolph
Shladover, Steven
1997

Automated Highway Systems (AHS) have the potential for offering large capacity and safety gains without requiring significant amounts of additional right-of-way. Since the general public will be the users of the AHS, human factors must play a pivotal role in the research and development of AVCS technologies and AHS operation. This paper focuses on fully automated AHS.To ensure the identification of all major human factors issues, we have identified major options for operating fully automated AHS. These options are categorized in the following four dimensions: separation of traffic,...

California System Architecture For Intelligent Transportation: Models For Transportation Systems Management

Hall, Randolph
Thakker, Viral
1998

In 1996, the Federal Highway Administration completed a program to develop a national system architecture (NSA) for intelligent-transportation-systems. This report presents recommendations on methodologies by which system architecture can be used to improve the deployment of transportation management projects, with emphasis on multi-jurisdictional projects. The report is part of a larger project addressing the deployment of an ITS system architecture in California. The project as a whole is led by Claremont Graduate School, and is documented in a separate report.

Supply Side Evaluation of Radio Traffic Information

Yim, Youngbin
Pfeifle, Brian
Hellman, Paul
1997

The study investigated data collection and dissemination processes of radio traffic information in the San Francisco Bay Area. Program directors from thirty two radio stations were interviewed to understand the processes and radio traffic reports were analyzed to evaluate the contents. The study showed that morning traffic conditions were broadcast most frequently. During morning peak hours from 6AM-9AM, the majority of the stations broadcast traffic conditions every 15 minutes. The content of the radio information is limited to traffic flow, incident conditions and transit schedule. The...

Configuration And Maneuvers In Safety-consciously Designed Ahs Configuration

Hitchcock, Anthony
1995

This paper sets out a configuration for an Automated Highway System (AHS) which is believed to have advantages from a safety viewpoint. The configuration and operating principles are described. The scheme requires that vehicles change lanes directly from platoon to platoon, and that entry and exit be made also without platoons merging or splitting on the automated lanes. The protocols for the maneuvers needed are described in detail.

Travinfo Evalution (technology Element) Traveler Information Center (tic) Study (september 1996 - June 1997)

Miller, Mark A.
Loukakos, Dimitri
1998

TravInfo is a Field Operational Test of advanced traveler information systems for the San Francisco Bay Area, sponsored by the Federal Highway Administration (FHWA). The project involves a public/private partnership which seeks to compile, integrate and broadly disseminate timely and accurate multi-modal traveler information through commercial products and services. The public sector component centers on the Traveler Information Center (TIC), which collects and integrates both static and dynamic traveler information. The TIC began operations in September 1996 and will operate as an FOT...

Travinfo Evaluation: Institutional Element Phase 1 Results

Hall, Randolph
Yim, Y. B.
Pfeifle, Brian
Weissenberger, Stein
1995

The TravInfo project aims to develop a multi-modal traveler information system for the San Francisco Bay Area, developing a partnership between the public and private sectors. This report presents the results of the first wave of institutional interviews, as part of the TravInfo evaluation.