At present, most literatures related to inventory decisionmaking are based on evendemand. Some literatures consider demand timevarying, but they don't study mutualinfluence and coordination of supplier and buyer's inventory decisionmaking. Along withincreasingly fierce competition, demand timevarying becomes more apparent. Supply chaininventory decisionmaking under timevarying demand longs for theory innovation. Basedon above reasons, this paper deeply studies supply chain inventory decisionmaking undertimevarying demand, puts forward corresponding inventory decisionmaking models, inorder to decrease supply chain inventory cost by optimization of supply chain inventorydecisionmaking. This research is based on Supply Chain Management theory, optimization theory,decisionmaking theory, game theory and inventory management theory. The researchmethods include model analysis, numeral analysis, comparative analysis and so on. In thecase timevarying demand is deterministic and there exist alternative supply source, basedon model derivation, this paper firstly obtains analytic models of supplierbuyer parties'optimal shortages times and service level, and analyses local and global optimization ofreorder cycle by comparison. The main conclusions are: global optimization of shortagestimes effectively decreases supply chain inventory cost; global optimization of reorder cyclemakes supply chain inventory cost decreasing, and decrease of inventory cost increases withdemand timevarying. This paper more studies optimization and coordination of supplychain inventory decisionmaking under nonequal cycle replenishment, puts forward localand global optimization equations of reorder times at the two parties, their computer processand computer programs. Main conclusions are: interval of local optimization reorder timeschanges with time under timevarying demand; under onetoone reorder, local optimizationof reorder times can decrease supply chain inventory cost; In general case, globaloptimization of nonequalcycle reorder times causes apparent decrease of supply chaininventory cost under timevarying demand. In the case timevarying demand is deterministicand there doesn't exist alternative source, this paper firstly studies game equilibrium ofshortages times and reorder frequency, based on model derivation, obtains the followingconclusion: the larger balance of supplier and buyer's reorder frequency is, using alternativesupply source more contributes to decrease of both parties' inventory cost; when supplier IIIand buyer's reorder frequency is near, supply chain inventory cost in two cases are almostequal, so using alternative source is unnecessary. Thereafter, this paper studies supplierbuyer game relation under nonequal cycle replenishment based on game theory, andobtains Nash equilibrium of both parties' shortages times, reorder frequency, reorder times,and puts forward supplierbuyer cooperation mode: the wholesaler fully satisfy retailer'sdemand and retailer globally optimize its reorder times. Main conclusion is: supply chaininventory cost without alternative source is apparently larger than that with alternativesource, and supplierbuyer cooperation becomes more necessary. Main conclusions are:supply chain inventory cost without alternative source is larger than that with alternativesource, and supplierbuyer cooperation becomes more necessary. In the case timevaryingdemand is random and there exists alternative source, this paper firstly studies optimizationof base inventory levels under equal cycle replenishment, based on model derivation,obtains local and global optimization equations of supplier and buyer's base inventorylevels. Main conclusion is: base inventory level by local optimization is timevarying, andthe more larger demand timevarying is, the more apparent base inventory level change.Global optimization's base inventory level waves round local...
