Study On Network Models And Optimal Strategy Of Agricultural Products Supply Chain

In China, the "Agriculture, Rural and Peasant" problem has become an overall, fundamental and strategic problem which relations with the country's stability and so-ciety's harmonious development. The basic outlet that solves the problem lies in the agricultural modernization. One of the bottleneck factors that restrict the agricultural modernization is the inefficient agricultural products supply chains, which has seriously affected the industry competitiveness of our country agriculture, and make it very difficult to cope with the grim challenges brought about by global economic progress. Therefore, the problem about the agricultural products supply chain has become one of the most imminent and urgent problems to resolve. The study has great academic sense and real significance in optimizing the supply chain of agricultural products, reducing cost, improving efficiency and the products'quality.In view of the several above key problems, relevant research is done in this paper, which is based on supply chain management theory, game theory, contract theory, behavioral economics and optimization theory. The main creative work is as follows: 1. Optimization design of distribution network for agriculture products supply chainA new mathematical model of Location Allocation Problem for agriculture products distribution network is founded, which is based on inventory control. The objective is to determine the rational numbers and position of distribution centers, the demand points which served by each distribution center, and the optimal order strategy of every distribution center and demand point. In this model, comprehensively considered factors of multi-item, deteriorating, imbalance transportation cost, inventory cost, service level, depreciation of fixed assets, and limited investment budget etc.. Therefore it is more practical.According to the characteristics of optimal problem, A heuristic parallel tabu search algorithm is presented. This algorithm first made space partition of the feasible solution, which based on the limited investment budget, then overcome the shortcoming of single point departure by parallel tabu search. In the followed parallel tabu search process, the initial solutions are obtained based on lest transportation distance. The simulation results show that it can reduce the search space and improve solving speed effectively.2. Inventory-distribution routing optimization of agriculture products distribution networkIn view of the two management modes, coalition chain and regular chain, two mathematical models of inventory-distribution routing optimization for two-echelon agriculture products distribution network are established. These models are based on one-to-many, interval periodic order, demand depend on inventory, deteriorating treatment cost of agriculture products, start-up costs of vehicles etc.. In the coalition chain, the wholesale price contract is adopted.According to the model of coalition chain, an heuristic adaptive genetic algorithm is presented. And for the regular chain, a two-layer genetic algorithm based on oddment modification is proposed. In the two-layer genetic algorithm, the upper layer is to determine the distribution periodic and quantity, and the lower layer is to seek the optimal order cycle, quantity and distribution routes of the distributor. Furthermore, the lower layer determines the rational oddment modification number, and optimal results are sent back to the upper layer. Based on simulation experiment, the validity of the algorithms is demonstrated, the Influence of fixed order cost and wholesale price in the coalition chain is discussed, and the two management modes are compared.3. Production optimization and coordination of agriculture products supply chain based on random yieldAccording to additive and multiplicative random yield respectively, stackelberg game models of two-echelon agriculture products supply chain are founded, in which the manufacturer is the leader with deterministic demand, the supplier is the follower with random yield. These models are based on wholesale price contract and the contracts combined with wholesale price, penalty for insufficient yield and purchase for surplus yield, and the objective is to determine the optimal production strategy and contract parameter to maximize benefits of the supply chain members.By theory and simulation analysis, the following results are obtained:(1) In case of multiplicative random yield, there is direct ratio relations between market demand of agriculture products, optimal order quantity of manufacture and optimal input quantity of supplier, in which the proportional coefficients depend on the contract parameters. In case of additive random yield, the difference value between market demand of agriculture products, optimal order quantity of manufacture and optimal input quantity of supplier is constant values, which depend on the contract parameters.(2) The contracts in this paper can realize the perfect coordination of the supply chain under multiplicative random yield conditions, but can not under additive random yield conditions.(3) In view of maximization the total profit of supply chain, flexibility of profit distribution and simplify operation, in the four contracts, the wholesale price contract combined with purchase for surplus yield is the best, then the wholesale price contract combined with penalty for insufficient yield and purchase for surplus yield, the wholesale price contract, the wholesale price contract combined with penalty for insufficient yield in sequence.4. Quality inspection optimization of agriculture products based on fairness preferences and incentive mechanism of suppliersBy taking a two-echelon agriculture products supply chain as the research object, which consisted of one leader manufacturer and two follower suppliers, a principal-agent model based on quality sampling inspection and fairness preferences is established. The objective is to determine the optimal sampling inspection rate, the optimal compensation contract and its parameters, which can motivate the suppliers to work hard and improve quality with manufacture's lowest incentive cost.By theory and simulation analysis under the risk-neutral assumption, the following conclusions are obtained:(1) The optimal sampling inspection rate is significant negatively correlated with inspection cost coefficient, and positively correlated with the product randomness. (2) Positive income of motivation benefit can obtained under the extreme relation achievement evaluation contract and the middle joint contract, and the return is positively correlated with inspection cost coefficient, and negatively correlated with the product randomness.(3) In terms of contact selection, when the inspection cost coefficient is little and the product randomness is strong, the extreme team achievement evaluation contract should be adopted, otherwise, it is inclined to the middle joint contract.