Author(s)

J L Kuhnau & K G Goulias

Abstract

Urban Airshed Models for estimating air pollution concentrations in a region require travel demand models that can produce hour-by-hour mobile source emission estimates, Regional simulation models of this type are currently created and tested in Australia, Europe, Japan, and the United States using a variety of theories, decision-making formalisms, and operational implementation methods. On one hand, these relatively new conceptualizations and models of transport systems have improved in a substantial way the realism of computerized decision support tools and have the potential of improving quantification of environmental impacts and transport management/control strategies. On the other hand, however, these systems require a substantial amount of data and understanding about behavior that very often are not readily available and for this require additional research. In this paper first a brief comparative overview of conceptual designs, data requirements, and models used in computer simulation of regional transport systems is provided. Then, the basic ingredients of a model system called Longitudinal Integrated Forecasting Environment (LIFE) that contains a demographic simulator, a daily time allocation and travel scheduling system, and a Geographic Information System are also presented. One component of this model system emphasizing the spatial and temporal dimensions of travel demand is described in more detail together with its validation using observed traffic data. The paper concludes with a summary and a few directions for model improvements.

Keywords