MetroFreight

1.2a <p>Modeling for Local Impact Analysis</p>

Project Number

1.2a

Project Summary

Modeling for Local Impact Analysis

Project Status

In progress

Year

2014

Topic Area

Sustainable Urban Freight

P.I. Name & Address

Professor of Electrical Engineering Systems, Ming Hsieh Department of Electrical Engineering; USC Viterbi School of Engineering
University of Southern California
3740 McClintock Avenue
Hughes Aircraft Electrical Engineering Center (EEB) 200B
Los Angeles, CA 90089-2562
United States
ioannou@usc.edu

Under this project we are developing a traffic simulation model for the Los Angeles/Long Beach region that will allow us to estimate impacts of existing freight flows as well as impacts of policy interventions or of land use changes.  The area is important for freight as it involves the twin ports and warehouses and freight hubs. The way freight is consolidated and distributed affects what is going on within the terminals and roadway network. The simulation model has two parts: a macro-simulation model for the region, and a micro-simulation model for a small area. The macroscopic model will focus on flows and will cover a much larger area as it is computationally much more efficient than the microscopic one. The microscopic model will model the motion of each truck and vehicles, traffic lights, stop signs, speed limits, traffic rules, etc., and resembles the real situation as close as it gets.

The up to date progress includes the following:

Improvement of Previous Port Model: One of the difficulties in combining a terminal model with the road network to operate together in real time as well as interact with other modules such as the environmental model/emissions model, terminal cost model is to describe these models in a programming language that makes it easy to interface each model in a continuous manner. For this reason we developed an object-oriented, event-based terminal simulation module implemented with the C++ programming language based on our previous terminal model. It realizes high degree of continuous data exchange and software integration with the traffic simulation module via COM interface. The design of this terminal module is shown in Figure 1 that includes a terminal object and other three objects used to generate truck input & output, ships and trains. This terminal module provides a complete simulation environment where a lot of simulation parameters are able to be set such as inbound/outbound gate processing times, ship and train arrives, inflows and outflows of storage yards, yard capacities, etc. Various methods are supported for configuring the truck arrival: 1) setting the truck arrival distribution parameters in the user interface; 2) importing a truck log file that stores truck arrival quantities with respect to simulation time as simulation input; 3) obtaining truck arrivals from traffic simulation module via COM interface automatically. The terminal simulation module provides time dependent and cumulative graphs of any interested variables within the terminal after running simulation successfully.  With a developed terminal cost model we can evaluate impacts on terminal operation costs of different scenarios. The use of C++ and object classes makes the model computationally efficient, expandable and reconfigurable. We have finished the coding of simulation part and are developing the user interface.

Figure 1

Fig. 1     Design of Terminal Module

Development of the Microscopic Traffic Simulation Model for the selected area of study: The traffic simulation module models the microscopic traffic flows on the roadway network around the port area. This module is built based on the traffic simulation software VISSIM.  Figure 2 shows current layout of traffic simulation module that consists of important freeways (405, 110, 103, 710, etc.) and main roads in the Long Beach/Los Angeles Port surrounding area. Using VISSIM, we coded traffic detection, freeway speed control, intersection signal control, vehicle compositions, traffic demand and routing decisions to support the simulation and evaluation of the impacts of existing freight flows as well as impacts of policy interventions or of land use changes. We are currently working on tuning the model using real data and dynamic assignment. We are interacting with Prof. Giuliano’s student with regard to truck data and freight demand in the selected region of education.

Figure 2

Fig.2      Micro-Simulation Traffic Module

Macroscopic Traffic Model for the region of study: The area covered by the macroscopic road network model is shown in fig. 3 below:

Figure 3

Fig. 3 Macroscopic model area

All the link information is added together with traffic light information, delays etc. We are currently in the process of gathering the OD matrixes where real data are available and estimate those not available via dynamic assignment. We are interacting with Professor Giuliano’s group to expand the above network to the detailed and larger scale network (Converted from the ArcGIS data by Professor Giuliano’s group), by focusing on what is computationally feasible by paying attention to the most important routes followed by trucks.  

Funding Source(s) and
Amounts Provided (by each agency or organization)

Volvo Research and Education Foundation

$95,646

Total Project Cost

$95,646

Agency ID or Contract Number

CoE-2012-01

Start and End Dates

9/30/2013 to 9/30/2017

Describe Implementation of Research Outcomes (or why not implemented)

 

Impacts/Benefits of Implementation (actual, not anticipated)

 

Web Links, Reports, Project website

http://metrans.org/research-projects/metrofreight