Urban Transport Modelling

Principal Investigators: Assoc. Prof. Lee Der-Horng

Executive summary

In literature, urban economists have focused extensively on the relationship between road transportation and land development. Large scale computable models such as those treated the efficient allocation of land between roads and other uses and modeled the relationship between road capacity, road use and equilibrium congestion with or without congestion tolls. However, this and other models developed within urban economics tend to focus on simple geometries and do not deal with real transport networks.

This project aims to adopt an integrative approach to address the interaction between land use and transportation.

The traditional land-use and transportation modeling, at urban activity level, considers the residential location and employment location problems. With the realization of urban activity, aggregate sequential travel demand forecasting with feedback loop will be conducted encompassing trip generation, trip distribution, mode choice (modal split), and route choice (traffic assignment). Note that analytical-based mathematical models used to be adopted in realizing the resulting travel and traffic patterns in the aggregate sequential travel demand forecasting procedure.

While no network representation with high resolution of the transportation system exists in the traditional modeling framework, hence, route choice and congestion fail to be treated explicitly. Scenarios of travel characteristics such as road pricing, public transportation systems, and pedestrian movements are also usually missing from the picture.

Consequently, a vital division of the proposed project is to establish the linkage between strategic planning and microscopic simulation of road traffic. With the advancements in computer technology, it is now feasible to represent and model urban transportation environment using computer simulation techniques with detailed and comprehensive delineations including but not limited to: traffic networks (road, arterial, expressway, freeway), traffic control devices (computerized traffic signal systems), traffic information (congestion advisory, parking guidance), traffic operations (bus lane, lane restriction, turn restriction, roadside parking), transportation modes (passenger cars, taxis, buses, transit lines, pedestrians), through visualized and microscopic traffic simulation. More importantly, inputs of travel patterns (in the form of trip origin and destination data originated from different land use patterns), travel behaviors (preferences in mode and route choices, driving behaviors) and perceptions of en-route/evolving traffic conditions can be modeled and integrated with simulation model.

Such type of integrated model will broaden our understanding upon the interaction between urban activities and transportation. It will also enable the systematic apprehension of urban activities centered by land use and transportation.

To summarize, this study will model the land use and transport and will evaluate a range of solutions that promote public transport usage and reduce car dependency. Given the time frame, there will be a real-life scale study based on an identified precinct within the city. The results can be pilot tested and where appropriate, the study can be extended to an island-wide coverage in future.