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1The second Strategic Highway Research Program (SHRP 2) Project C10B, Partnership to Develop an Integrated, Advanced Travel Demand Model with Fine-Grained, Time-Sensitive Networks: Sacramento-Area Application, is an important step in the evolution of travel modeling from an aggregate, trip-based approach to a completely dynamic, disaggregate methodology. In this proj- ect, an existing disaggregate activity-based model (ABM) was integrated with an existing traffic simulation model to create a new, completely disaggregate model. This report describes the DynusT (Dynamic Urban Systems for Transportation) dynamic traffic assignment (DTA) model and the FAST-TrIPs (Flexible Assignment and Simulation Tool for Transit and Intermodal Passengers) DTA package and how these two model systems interact with each other and with the DaySim ABM implemented in Sacramento, California, to compose an integrated ABM and DTA model. This work was performed as part of the SHRP 2 Project C10B, Partner- ship to Develop an Integrated, Advanced Travel Demand Model with Fine-Grained, Time-Sensitive Networks. DynusT is a simulation-based DTA model capable of performing daily regional simula- tions of large metropolitan areas that involve many millions of trips, a feature necessary for DTA and ABM integration. This document describes in detail the traffic simulation and assignment capabilities of DynusT that capture capacity constraints, congestion, and queue propagation for various types of vehicles, including transit vehicles, and allow the generation of time-dependent level-of-service (LOS) measures that are closer to traffic theory. It also describes in detail the meth- odology that is used internally by DynusT to determine the time-dependent least-cost path route for each driver, a concept that is described as âdynamic user equilibrium.â FAST-TrIPs is a region- wide DTA model that determines an individual-specific transit route for each transit traveler in the system, taking into account published transit schedules and transit vehicle run times that are con- gestion responsive and are provided by the traffic simulation component of DynusT. FAST-TrIPs deals with both transit-only and park-and-ride trips and is able to maintain multiple constraints associated with activity time-windows and the choice of modes in multimodal travel tours. This report describes how DynusT and FAST-TrIPs interoperate with each other to provide a model system in which the highway and transit assignments influence each other and are based on the same set of LOS variables. Executive Summary
