Modeling

A Link-Based Variational Inequality Model for Dynamic Departure Time/Route Choice

Ran, Bin
Hall, Randolph
Boyce, David E.
1995

The dynamic user-optimal (DUO) departure time and route choice problem is to determine travelers’ best departure times and route choices at each instant of time. In a previous paper, we presented a route-based two-level optimal control model for the DUO departure time/route choice problem. However, this model is not appropriate for large scale transportation networks because some degree of route enumeration is necessary to solve the model. In this paper, we present a link-based variational inequality (VI) formulation for the DUO departure time/route choice problem so that route enumeration...

Institutional, Organizational and Market Aspects of Successful ITS Deployment: A Case Study Analysis

Conroy, Patrick
2003

This research follows on a previous study to explore key aspects of successful Intelligent Transportation Systems (ITS) deployment within existing institutional, organizational and market environments. The researcher developed three additional case studies of successful ITS deployment in the U.S. and Europe, and revisited one case from the previous work. Results from literature searches and surveys were analyzed, and findings on institutional, organizational and market factors are presented. Key words: ITS, deployment, institutional, value, business models, benefits, highway capacity

Integrated Traffic and Communications Modeling Environment for ATMIS

Varaiya, P.
Walrand, J.
Wu, F.F.
Polydoros, A.
Sylvester, J.
1997

The aims of this MOU were to create an integrated environment for modeling traffic flow, sensor data, and the communications infrastructure for ATMIS. The research plan was to build separate tools for measuring the communications requirements of ATMIS traffic, modeling a mobile radio communications environment, and communications network design, and then to integrate them in an object-oriented environment from which one could also access existing or new road traffic simulation packages.Section 1 of the report presents a framework for estimating the vehicle-roadside communications...

PATH ITS Research Digests

Chira-Chavala, Ted
2001

Ramp meters are commonly used to relieve congestion on freeways. What is the value of these systems? Ramp metering can alleviate recurrent, regular traffic congestion, such as that caused by the daily commute. The goal is usually to maintain uninterrupted freeway flow at a certain acceptable level, but it transfers delay to the entrance ramp, where excess demand is forced to wait. This report summarizes ramp metering technologies, reviews the algorithms commonly used with them, and uses a traffic simulation model to identify the benefits and costs of using these systems. We used a...

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)...

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...