Urban Population Mobility Simulation Technologies (UPMoST)

The Urban Population Mobility Simulation Technologies Module provides a common interface for the flow of information between UIS sector simulations. UPMoST serves as the central link of the UIS that allows us to model and analyze the complex interdependencies among various urban infrastructures.

All information describing the synthetic population and elements of the built urban environment generated by the Transportation Analysis Simulation System (TRANSIMS) flows through UPMoST to the other UIS modules. In addition, changes in the urban infrastructure arising during the course of a simulation that constrain activities and locations of the population pass between the modules through UPMoST, where sector-specific information is transformed into a common format.

Key Features

UPMoST makes information available to the other UIS modules in the form of a consistent data structure called an UPMoST entity. An entity can represent a person, a vehicle, or an infrastructure element such as a hospital. Each entity is identified by a unique identification number.

Entity information is divided into two types: (1) static information that does not change over the course of a simulation, such as age, income, and home location, and (2) time-dependent information such as an individual’s location, activity type, and health status.

UPMoST contains an Entity Creator module that takes population-mobility data from TRANSIMS, filters and collates the data, and produces UPMoST entities, which are sent to the other UIS modules.

The figure at right shows the data flow into the Entity Creator module. The figure below shows the process used by the Entity Creator module to create UPMoST entities.

UPMoST’s ability to handle data sets larger than 10 gigabytes, for instance to simulate a metropolitan area, is due to the parallel-execution capability of the Entity Creator module. All of the UIS modules use a common architecture for data exchange that originates in UPMoST. Accessing the data usually requires an indexed-lookup capability that is supported by UPMoST. UPMoST entities encapsulate city-specific information in a generic data format; the generic methods used to generate UPMoST entities can be applied to any city.