Modeling

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...

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...

Freeway Detector Data Analysis For Simulation Of The Santa Monica Freeway - Summary Report

Bloomberg, Loren D.
May, Adolf D.
1993

The objective of this study is to collect, organize, analyze, and summarize available detector data for the Santa Monica Freeway. The primary goal is to develop on/off ramp counts as input to a synthetic origin/destination model; mainline freeways counts are also needed. Strategies for synthesizing data from stations where current detector data are unavailable are also considered. This report is a revised version of UCB-ITS-PWP-93-1 (PATH Database record #4079)

Some Aspects of the Market for Broadcast Traffic Information

Malchow, Matthew
Kanafani, Adib
1999

In recent years, planners have looked toward traffic information systems as an immediate solution to the congestion on U.S. highways. ITS systems are low-cost relative to many alternatives, and simple implementation allows for quick results. Alongside these investments has been research investigating the use of information systems by drivers and the results to be expected. Many studies have shown that the primary source of information for drivers has been broadcast systems such as the radio (e.g. Yim et al., 1997). Additional research has addressed other media which are used to transmit...

Studies of Vehicle Collisions - A Documentation of the Simulation Codes: SMAC (Simulation Model of Automobile Collisions) [ Diskette Included ]

Chan, Ching-Yao
1998

This document describes part of the work conducted under MOU252 and MOU324, related to the studies of vehicle collisions in vehicle-following operations. This working paper is a detailed documentation of a computer program that is the core element of the simulation tools for vehicle collision dynamics. The program, SMAC (Simulation Model of Automobile Collisions), and its PC-platform version EDSMAC have been used extensively in recent work at PATH to investigate the consequences of vehicle collisions and the effects of vehicle-following parameters on collisions. A copy of the source codes...

Integrated Smart Feeder / Shuttle Bus Service

Ceder, Avishai
Yim, Youngbin
2003

This paper presents the design of an integrated smart feeder/shuttle system. The design of such a system was motivated by the need to provide easy access to main haul transit services. Park and ride lots in many train stations can no longer accommodate automobiles brought to the stations. Some train riders have switched their mode of transportation from public transit to solo driving. Shortage of parking spaces at rail stations encourages passengers to drive alone, hence more cars on freeways and worsening traffic congestion. The purpose of this study is to design an innovative feeder/...

LANE-OPT Users Manual Version 1.0

Lotspeich, David
Hall, Randolph W.
1996

This document is the user manual for LANE-OPT. LANE-OPT is a linear program based software package that optimally assigns traffic to lanes on an automated highway. The program is based on a workload model, such that each lane/segment has a fixed capacity than can be allocated among: (1) straight traffic, (2) lane changes into the lane, (3) lane changes out from the lane, and (4) lane changes that pass through the lane. Each of these four movements produces a user-specified workload. The computer program models the highway as a multi-commodity flow network, where commodities represent...

Are the Objectives and Solutions of Dynamic User-Equilibrium Models Always Consistent?

Lin, Wei-Hua
Lo, Hong
1996

Traffic assignment models are an important component in analyzing the relationship between demand and supply in the transportation network for design, planning, and control purposes. The static traffic assignment model has been used in practice for several decades. With the latest development in the area of Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS), there is an increasing demand for dynamic traffic assignment models to serve as a basis for studying various issues in these areas.Existing dynamic user-equilibrium traffic assignment (DUETA)...

Beyond Tele-substitution: A Broader Empirical Look at Communication Impacts

Mokhtarian, Patricia L.
Meenakshisundaram, Ravikumar
1998

Information on the number and types of communication activities (including travel) engaged in over a period of four consecutive days, at two points in time about six months apart, was collected from 91 respondents. A system of structural equations was developed and estimated, expressing the quantity of each type of communication at time 2 as a function of quantities of communication of each type at time 1, the elapsed time between measurements, and exogenous sociodemographic variables. All "own" lagged effects (that is, the effect of one communication type in wave 1 on the same type of...

Optimized Lane Assignment on an Automated Highway

Hall, Randolph
Lotspeich, David
1996

Highway automation entails the application of control, sensing and communication technologies to road vehicles, with the objective of improving highway performance. It has been envisioned that automation could increase highway capacity by a factor of three. To attain this capacity, it will be important to minimize the amount of lane-changing and optimally assign vehicles to lanes. This paper develops and applies a linear programming based lane assignment model. The highway system is modeled as a multi-commodity network, where the commodities represent trip destinations (i.e., exit ramps on...