Abstract: In view of the salvage value or replenishment problem caused by the output and demand uncertainty, considering a bilateral random supply chain consisting of a single manufacturer and retailer, the two sides take the form of pre-order to construct two different spot-market replenishment strategy models, and study the optimal decision-making behaviors of input quantity of raw materials and order quantity of finished products, and supply chain coordination problem under random environment. The research shows that when the retailer replenishes the products by itself, the revenue sharing contract cannot cope with the risk of output uncertainty, and the manufacturer will reduce the input to avoid the overproduction, which will lead to the contract failure. However, the revenue sharing contract attached with the two-way mechanism of penalty for shortage and compensation for surplus can work effectively. When the manufacturer replenishes the products, the spot market reduces the output uncertainty risk and improves the ratio of output on input of the chain system, and can make the original revenue sharing contract work again. After the coordination of effective contracts, the profits of all parties are affine functions of the optimal profits of the system, and the distribution coefficient is controlled by the revenue sharing proportion after negotiation. Theoretical analysis and numerical simulation demonstrate the effectiveness of contract coordination. It is also found from the numerical analysis that the designed revenue-sharing and risk-sharing contract can better reduce the impact of uncertainty on revenues than the single contract.

Key words: uncertain environment, spot market, replenishment strategy, supply chain contract