The survival rate of the patients in medical emergencies depends on the minimize ambulance arrival time on-sites and promptly provides medical care to the patients. Advanced Life Support (ALS) ambulances play a critical role in reducing the fatal and severity rate of emergency patients. The several areas in big cities always encounter with traffic congestion, which is a significant obstacle for ALS ambulances to achieve their service time window target (predetermine as less than 8 min). In light of prior research, arranging appropriate parking locations can solve such a problem. This study proposes a mathematical model of facility location problem to identify the ALS ambulances parking locations. This paper simultaneously considers the minimize of the total number of ALS ambulance parking locations while covering the service areas and service time window are fulfilled. One part of business centers in Bangkok was chosen to correct the data and test the proposed model. This study is distinguished from others in these areas by the only possible parking places, i.e., schools, temples, police stations, and gas stations, which are taking into consideration. IBM ILOG CPLEX Optimization Studio Version 12.6.1 was utilized to solve the problem. The result indicates that there are 26 parking locations, which can enable the service coverage areas. As well as achieve a 54% service time window target.

Presently, the growing challenge of Reverse Logistics (RL) transportation has broadly received attentions in supply chain management area from both scholars and practitioners. When products have reached their end-of-life they have to enter into reverse chain for the purpose of either recycling, repair, re-manufacturing, or re-use. As a matter of fact that the cost of transporting products through a reverse supply chain is often higher than moving the original product from the manufacturer to the consumer. A well-organized reverse logistics network especial transportation can lead to save cost, increase revenue and customer satisfaction. The optimized reverse logistics transportation is one of the crucial tasks for enterprises to gain the competitive advantage from their supply chain network. This paper aims to optimize the transportation cost of end-of-life lead- acid batteries between the recycle consolidation centers and smelting manufacturers. A Linear Programming (LP) model was formulated in order to solve the transportation problem. The two scenarios of transportation service fees (cost per volume versus cost per trip) were comparison. The proposed approach was applied to real case in central region of Thailand. The numerical experiments was executed to minimize the transportation cost of the system on both scenarios. In term of total transportation cost of system, the result from this study indicated that cost per volume scenario is lower than cost per trip scenario.