Transportation engineers and planners attempt to understand urban travel characteristics to
develop, formulate, and analyze problems and opportunities better. Transportation
professionals use urban transportation models and typically implemented the four-step
urban transportation planning process. This study examined a modified planning process
that preassigned external trips to the transportation network before distributing and
assigning internal trips. The preassignment, or preloading, of external trips helped to ensure …

Transportation planners use urban transportation planning models, which are
representations of the existing or future transportation infrastructure in order to determine the
impacts of future changes on the transportation system. Included in the sequential modeling
process are trips that begin or end outside the study area. These trips are referred to as
external trips in the model. There are two distinct external trips purposes typically modeled:
internal-external and external-external. Internal-external trips have either an origin or …