Research On Decision-making Of Input Quantities And Coordination With Random Yields

With the development of economy and the progress of technology,customers’individualized and diversified needs are growing,the life cycle of products is shortening.The competition focus between enterprises includes not only price,quality and costs,but also customer service and response time.For the short-life-cycle products,regardless of traditional retail channels or online direct selling,under the mode of MTO,the demands that the manufacturers face may be determined.For the supply chain consisting of a manufacturer and a supplier,the supplier offers core materials to the manufacturer,as the customers placing the orders,the manufacturer determine the ordering quantities(or input quantities)of materials,then the supplier makes decision of input quantities of materials.Under the influence of random factors such as environment,process,employees,equipment,emergencies,materials and management,the yields rate of each enterprise may be random.As the outputs and demands are not matched,it raises a series of problems such as resources waste,high inventories of WIP,delayed delivery time,and low customer satisfaction.When the members of supply chain or the production organizations of the manufacturer make decisions under decentralized situation,the double marginal effects would exist.Therefore,it is necessary to establish a supply chain contract coordination mechanism to improve performances.Considering that the demands are determined and the yields of the manufacturer and supplier are random,the paper studies the problems of input quantities decision-making about the manufacturer and the manufacturer-supplier supply chain based on Newsboy Model,and it compares the optimal input quantities and expected profits of various organizations under different situations such as purchasing strategies,transaction contracts and operation decisions.From the perspective of quantitative research,it proposes the supply chain coordination mechanism about revenue sharing,risk sharing,wholesale price discount,insufficient outputs penalty and option contract.From the perspective of qualitative research,the paper puts forward measures to improve the yields rate and save production costs,and analyzes the functions of the Amoeba organization and gives the basic conditions for the implementation of Amoeba operation,and studies the impacts of lack of coordination on supply chain performance.Finally it informs the supply chain coordination mechanism and option contract coordination mechanism under fixed procurement strategy and flexible procurement strategy.The above research provides theoretical and methodological support to strengthen manufacturers’ schedule control and costs control,and promote cooperation between the members of supply chain,and improve the demand resilience,and promote strategy,it proposes a coordination mechanism about comprehensive contracts of revenues sharing,risk sharing and outputs insufficient punishment.The main conclusions are showed as follows:(1)The existence and uniqueness of the optimal solutions are feasible under certain conditions regardless of decentralization or centralized decision-making.(2)For both the procurement strategy,the optimal input quantities of the manufacturer and the supplier under centralized decision is greater than the ones under decentralized decision,and the total profits of the supply chain under centralized decision is also greater than the ones under decentralized decision.(3)For the decentralized decision,the optimal input quantities of the supplier are closer to the ones of the manufacturer under flexible procurement strategy compared to the fixed procurement strategy.(4)The changes of parameters related to the manufacturer have a great impact on decisions of the supplier,while the changes of ones related to the supplier have little impact on decisions of the manufacturer.(5)To achieve supply chain coordination,the wholesale price can be appropriately reduced,but in order to achieve Pareto improvement about each player,the manufacturer should undertake some output risks of the supplier.For the supply chain consisting of a manufacturer and two suppliers that the manufacturer signing a wholesale price contract with the primary supplier and an option contract with the alternative supplier(named as comprehensive contract),the paper establishes the Stackelberg game models about the fix and flexible procurement strategies under decentralized decision,obtains the expression about the manufacturer’s optimal initial input quantities,option ordering quantities and the primary supplier’s input quantities,and the optimal performance of all players,then it proposes a supply chain coordination mechanism based on comprehensive contract and qualitatively analyzes coordination strategies for the members of supply chain.It compares and analyzes the ordering/input quantities and optimal performance of all players under eight situations such as different contracts,different procurement strategies and different operating decisions,so that the conclusions are followed as below:(1)Under the two purchasing strategies,the optimal solutions of various models are existent and unique.(2)The manufacturer’s optimal input quantities and the supplier’s input quantities are different under various circumstances.In general,the manufacturer’s initial order quantities are minimal under flexible procurement strategy and whole price/option contract and maximum under flexible procurement strategy/centralized decision,while the supplier’s input quantities are minimal under flexible procurement strategy and whole price/option contract and maximum under fix procurement strategy/centralized decision.(3)For the manufacturer,the relatively best option may be the fixed procurement strategy and option contract.For suppliers,the relatively best option may manufacturers’ transformation and upgrading.The specific contents and main conclusions are as follows:For the input quantities decision of single-stage of the manufacturer,it considers that the yields rate of the initial production and rework rate are constant or random,and establishes models to proves the existence and uniqueness of the optimal solutions and gets the optimal performance under various circumstances.The main conclusions are showed as follows:(1)The internal and external environment is more stable,the profits are larger.(2)The fluctuation of demands or outputs is greater,the profits are lower.(3)The factors of unit price or costs affect the profits of the manufacturer from the largest to the smallest are the unit production costs,the price of finished goods,the unit rework costs,the unit residual value and the unit costs of expedited production.For the input quantities decision of internal multi-level stage of the manufacturer,it designs the management mechanism based on the mode of Amoeba operation,the workshop is divided into multiple organizations of Amoeba that are relatively independent and the adjacent Amoebas can decide the price and trade with each other.Under decentralized decision-making,it establishes the Stackelberg game model about decision of planned input quantities of each Amoeba and the guaranteed delivery time of the manufacturer based on the mechanism of insufficient outputs penalty.Under the centralized decision-making,it establishes a Nash game model about multiple variables of input quantities based on the resource sharing mechanism.the performance distribution for each Amoeba is realized based on the mechanism of penalty costs sharing and the spot market procurement costs sharing.Then it analyzes the incentive mechanism for each production organization of the manufacturer.The main conclusions are as follows:(1)The expected profits function of each Amoeba organization under decentralized decision-making and the overall expected profits function of the workshop under centralized decision are concave.(2)For the same Amoeba organization,the optimal input quantities under centralized decision-making is less than the decentralized decision.(3)When the average yields rate of each stage is smaller,the volatility of the yields rate is greater;the unit purchasing costs from the spot market and the unit expedited production costs is higher,the manufacturer has less profits.For the supply chain consisting of a manufacturer and a supplier based on a wholesale price,it establishes the game models about input quantities decision of each player under the decentralized and centralized circumstances respectively for the fixed procurement strategy and flexible procurement strategy,and obtains the optimal solutions and corresponding performance.For the fixed procurement strategy,it proposes a coordination mechanism of revenues sharing,wholesale price discount and risk sharing.For the flexible procurement be the flexible procurement strategy and wholesale price contract.For the supply chain,regardless of any strategies,the whole profits of all the members under whole price/option contract is generally higher than the ones under centralized decision or wholesale price contract-decentralized decision.(4)Generally,under the option contract,the smaller the option price and the option executive price,the more beneficial to the manufacturer;the larger the option price and the option executive price,the more favorable to the primary supplier.Under different purchasing strategies,the relationship between the expected profits of the alternative supplier and the change of option price and the option executive price is obviously different.(5)Under the whole price/option contract,the larger the wholesale price,the more harmful it is for the manufacturer while more favorable for the suppliers,the influence on the whole performance of all the players is not regular.The profits of the entirety is maximum when the wholesale price is a certain appropriate value.