FRISM 2.0.0

The Freight Integrated Simulation Model (FRISM) is an agent-based freight model for medium-term (day-to-day) shipping decisions. This model has the capability of linking between shipments generated at the firm level and vehicle operations to delivery shipments. FRISM focuses on determining a vehicle type for a shipment, assigning shipments to a fleet owned by a shipper or carrier, and then making a fleet operations plan. As of now, it is limited to on-road vehicle operations at a regional scale but can be extended to non-road modes. Additionally, acknowledging the rise in the e-commerce market and its impact on regional freight traffic, FRISM can predict households’ e-commerce demand as part of their daily shopping activity. Simulating e-commerce demand and associated last-mile delivery truck movement is expected to fill the gap in conventional freight models focusing on firm-based commodity trade.

The operational FRISM, including the main functionality summarized below, has been developed and implemented. Work is ongoing to enhance certain models, such as on-demand delivery assignments to carriers and parking/charging location choices in tour plans.

1. Daily shipment generation: FRISM simulates daily firm-to-firm shipments using exogenous inputs from an upstream model (e.g., SynthFirm) and individual/household’s online shopping demand. For the firm-to-firm shipments, the demand for on-road vehicle modes is utilized in the current implementation with a focus on on-road fleet operations plans. For the online shopping demand, FRISM predicts grocery and prepared meal shopping (defined as food shopping) and shopping for other items (defined as general shopping) using a set of synthetic population data, which is an exogenous input from a passenger model.
2. Shipments assignment to fleets: A carrier agent is a key agent in FRISM. Carriers can be shippers who have their own fleets or logistics companies who provide delivery services. Shipments generated by firms and households are assigned to those carriers based on shipment characteristics and vehicle availability. Heuristics approaches based on the observed probability have been applied to capture the relationship between vehicle types and commodity types and the contract between shippers and logistics companies.
3. Fleet operations planning: FRISM generates pre-day tour plans for the available freight vehicles to transport shipments from their shippers to receivers. By assuming that each carrier makes plans to optimize its operations, a vehicle routing problem (VRP) is applied for each carrier, constraining the receiver’s time window and vehicle capacity.