Replenishment Cycle Optimization of JIT Manufactory

In order to improve the JIT logistics theories, logistics optimization between JIT manufactory and supplier with mixed line production is researched in the paper. Inventory cost, transportation cost and production cost of both manufactory and supplier are integrated optimized. Logistics flow of the JIT system is analyzed. Inventory trend figure during JIT production is drawn. Optimization model of the logistics system is set up. The problem is solved with mathematics methods. The optimal shipping cycle time is obtained, and the minimal total cost is calculated. The research results indicates that the shipping cycle time affects the inventory cost, the transportation cost, the manufacturing cost, and consequently affects the supply system cost, and the optimal solution of the supply system exists and can be solved with the mathematics methods.