METRANS Associate Director of Research Professor Petros Ioannou has recently released his research and development of complex real-time simulation models that could provide much more efficient routing decisions than currently made.  His research project is titled “Optimum Routing of Freight in Urban Environments under Normal Operations and Disruptions using a Co-simulation Optimization Control Approach.” His full research report can be viewed through this link.

The City of Los Angeles and the City of Long Beach are two important urbanized areas within the Los Angeles Metropolitan Area, especially when it comes to international trade and shipping industry. The ports of Los Angeles and Long Beach combined are United States’ busiest seaports and airports. Additionally, they are a hub for technology, petroleum, fashion apparel, and tourism. Due to its unique position on the supply chain, this area has become a central node that experiences a high level of both freight and passenger traffic. Transportation infrastructures are also mostly shared by both modes at this region. Freight transportation and passenger transportation differs in multiple aspects, vehicle sizes and fuel consumption to name a few. This leads to many challenges.

Previously, many researchers have tried to solve this multimodal transportation problem. Many of them deviated from optimality because of using oversimplified mathematical models. Besides, most of the models were not real time based, thus lacking the capability to deal with incidents during normal transportation operations. Ioannou has developed complex real-time simulation models that could provide much more efficient routing decisions. 

In his research, Ioannou proposed a method named COSMO (Co-Simulation Optimization). It is an approach that uses real-time simulation models to estimate marginal costs of the routes and then applies an optimization algorithm to calculate the minimum cost route. Ioannou added a novel load balancing algorithm in the COSMO approach to redistribute the freight loads among current used routes if they are no longer the minimum cost routes. As a result, the real-time simulation model, the load balancing algorithm and the optimization module are integrated into an iterative feedback loop (shown in the blow graph). The load is redistributed within the network iteratively to reduce the overall cost.

Case study results from Los Angeles and Long Beach using this new approach indicated that the COSMO approach is substantially more effective compared to initial solution, especially in the case of unpredicted events that cause congestion and accidents. Further application of this new approach may help increase transportation network efficiency in the Los Angeles Metropolitan Area.

Professor Petros Ioannou

Petros A. Ioannou received the B.Sc. degree with First Class Honors from University College, London, England, in 1978 and the M.S. and Ph.D. degrees from the University of Illinois, Urbana, Illinois, in 1980 and 1982, respectively. During the period 1975-1978, he held a Commonwealth Scholarship from the Association of Commonwealth Universities, London, England. He was awarded several prizes, including the Goldsmid Prize and the A. P. Head Prize from University College, London. From 1979 to 1982 he was a research assistant at the Coordinated Science Laboratory at the University of Illinois. In 1982, Dr. Ioannou joined the Department of Electrical Engineering-Systems, University of Southern California, Los Angeles, California. He is currently a Professor in the same Department and the Director of the Center of Advanced Transportation Technologies. His research interests are in the areas of control and applications, adaptive and nonlinear systems, vehicle dynamics and control, intelligent transportation systems, marine transportation, congestion control of computer networks and neural networks.

Read more at http://ee.usc.edu/faculty_staff/faculty_directory/ioannou.htm

Shichun Hu

Author Shichun Hu is a student assistant at METRANS Transportation Center specializing in and coordinating the METRANS Mentor Program. She is a 2nd-year graduate student majoring in Industrial and System Engineering in the Viterbi School of Engineering, USC. Her interests are using data and operation research methods to improve urban logistics and the supply chain. She is pursuing analytical and operational jobs in these fields.