Multiple period vehicle scheduling problem with stochastic demand and delivery smoothing

This paper proposes modified vehicle scheduling problem to maximize resource utilization, so as to minimize necessary stocking spaces, inventory levels and shortages. Multiple period delivery scheduling problem in a system with one depot and N retailers is considered. The depot is responsible for replenishing inventories in the retailers. Stochastic demand is considered, and an algorithm for the delivery scheduling is presented introducing surplus delivery and backward approach of delivery smoothing. Through numerical experiment using real data of AVM (Automatic Vending Machine) and common test data from an ftp site, resource utilization is increased to 99.67%, while the average stocking space is decreased by 17.35%, average level of inventory is decreased by 25.7%, and average ratio of stock out is decreased by 14.77%.