Research On Variational Inequalities Equilibrium Model Of Multi-commodity Supply Chain Network With Random Demand

With the development of modern science and technology, the market demand is more and more difficult to grasp, then the supply chain mode which is based on the mutual cooperation between enterprises. But in reality each node enterprise of the supply chain can has multiple precursors and multiple successors, and the supply chain network is formed when these node enterprises in turn connected each other. In the supply chain network, the interests of the individual often inconsistent, policymakers will compete with each other to obtain more resources, so how to depict the supply chain network structure and competition or coordination relations between internal members in order to achieve the balanced state of the supply chain network system is very important.The first chapter elaborates the background and significance of supply chain network research, summarizes the effect of random demand to supply chain network, and describes the background and current situation of closed loop supply chain network research.The second chapter introduces the variational inequality theory including the relationship between variational inequality and optimization theory, variational inequalities and complementary problem, variational inequalities and Nash equilibrium, and the solution algorithm of variational inequality.The third chapter analyses influence of advertisement on demand, and the study shows that the advertisement is good for the increase of market demand. For a multi-commodity flow supply chain network which consists of multi-manufacturer, multi-retailer and demand-market, under the assumption that the manufacturer is responsible for the nationwide advertising investment, retailers bear regional advertising costs, this paper studies the influence of advertisement on demand. The competitive equilibriums among manufacturers and retailers are studied by Nash equilibrium analysis method and the variational inequality method. Stochastic utility theory is used to analyze stochastic choice in demand market, and the variational inequality model of the multi-commodity flow supply chain network is set up. Finally, a numerical example is given to show the rationality of the model.The fourth chapter gives the equilibrium conditions and economic interpretation of supply market, retail market and demand market in multi-commodity supply chain network with random demand by using Nash equilibrium theory and variational inequality method. Variational inequality models are set up to characterize the equilibrium states of each layer and whole supply chain network. When market demand is disrupted by an unexpected event, the original equilibrium state of supply chain network can’t be kept. The fluctuation of price at demand market led by the contraction between supply and demand will result in the operational risk of supply chain. Assume that manufacturers allow retailers having opportunities to replenish inventory and return residual products, this paper analyzes the change of equilibrium states of supply market, retail market and demand market with disrupted demand respectively, and puts forward the equilibrium model of multi-commodity supply chain network with random demand coping with demand disruption. Numerical examples show the reasonableness of models and the validity of the second order and return contracts coping with demand disruption.The fifth chapter presents a multi-commodity flow supply chain network model with multiple tiers of decision-makers, consisting, respectively, manufacturers, retailers, demand markets and recycling centers, who can compete within a tier but may cooperate between tiers. This section studies the manufacturers’and the retailers’ multi-criteria decision-making and the retailers’decision-making under random demand. Then the paper analyzes the multi-commodity closed-loop supply chain network and gives the sensitivity analysis on environmental protection consciousness and subsidies.In this thesis, the methods of economics, management, game theory and variational inequality theory are applied comprehensively to study the supply chain network with random demand under three situations such as advertising, demand disruption and multi-criteria. The results in this thesis have some theoretical value for the supply chain management.