Integration Of Ab Models And Microsimulation Models

摘要

Both activity-based (AB) models on the demand side and traffic microsimulation (TM) models on the supply side have been intensively developed as an alternative to traditional 4-step aggregate models that are based on static assignment procedures. AB models are based on microsimulation of individual behavior in terms of activities and trips undertaken during the day. TM models deal with individual vehicles' behaviour in the highway network. In both cases, moving from aggregate into disaggregate framework ensures a better behavioural realism and avoids aggregation biases. AB and TM Models are compatible in terms of temporal resolution. Advanced AB models today operate with 30 min intervals in terms of activity and trip schedules. TM models operate with even finer temporal resolution in terms of demand slices. Traditional 4-step models operate with broad 3-4-hour time-of-day periods and cannot provide an input to TM models with the necessary level of temporal detail. In the same vein, conventional static assignment represents a very problematic counter-partner for an AB model with a limited functionality. In particular, it has been recognised that travel times generated by static assignment under congestion' conditions are very crude since they do not account for queuing as well as for dynamic time-dependent effects.