Improving Emergency Goods Transportation Performance in Metropolitan Areas under Multi-echelon Queuing Conditions

AbstractA transportation network plays a crucial role in delivering emergency goods to people affected by natural and manmade disasters. The purpose of emergency goods transportation is to rapidly provide the appropriate emergency supplies to the disaster-struck areas. This requires a systemic coordination to prioritize the allocation of goods to desired locations. The concept of queuing is well documented in social service literature and transportation engineering literature. However, the queuing concept is limited for analyzing multi-echelon emergency transportation systems which are much more complex than other traffic networks. This paper develops a multi-echelon queuing network model of an emergency goods transportation intended to accelerate goods transportation and to reduce the waste time. The methodology captures differences in humanitarian relief demands, arrival patterns, volumes, and efficiencies of processes in logistics systems of disaster-struck areas. The relief goods stored in multi-echelon locations in a metropolitan area are delivered with an optimization method of the queuing equations by using sojourn time, waiting time, queue length, and overflow probability as quality of service. The multi-echelon queuing model is to minimize both response time in the emergency and transportation time on the road network, and a genetic algorithm is developed to solve the model. Then this method is applied to the comprehensive emergency goods transportation network in the Shanghai metropolitan region. The proposed analysis can be used as tools for improving coordination performance of an emergency goods transportation network