Abstract: Considering a system with multi-suppliers and a manufacturer,the lot size models of both respective replenishment and cycle replenishment from suppliers in the situation of supply-hub are presented.The analytical result shows that,when the freight cost of unit spare parts is sensitive to the volume of carrier,the cycle replenishment along milk road from suppliers is superior to the respective replenishment from suppliers.However,when the freight cost of unit spare parts is rigid to the volume of carrier,it is vice versa.Moreover,the difference of demandfor different spare parts has impact on the choice of replenishment methods.

Key words: supply chain, respective replenishment, cycle replenishment, lot size model