Bierlaire, M., Mishalani, R., and Ben-Akiva, M. (2000)

General framework for Dynamic Demand Simulation

The development and evaluation of Dynamic Traffic Management Systems (DTMS) for Intelligent Transportation Systems (ITS) applications require sophisticated simulation tools. Many traffic simulators representing traffic at various levels of aggregation have been developed and used. Despite the importance of demand in this context, these tools focus mainly on the supply aspects of the transportation systems. Demand is usually just an input to the simulator. The lack of dynamic demand simulators seems to be due to the difficulty of combining different models (like discrete choice models and OD matrix estimation) within a common environment. Therefore, a unifying framework, where different models can cooperate, will provide the necessary incentives for the development and implementation of a new class of dynamic demand simulators. In this paper, we propose a general framework for the design and development of dynamic demand simulators. It is sufficiently general to encapsulate a wide variety of applications, models, data and algorithms. The paper not only describes the conceptual framework, but also provides several practical considerations. The framework is illustrated using a dynamic demand simulator implemented within DynaMIT, a real-time dynamic traffic assignment system.