Researches On Supply Chain Inventory And Finance Decision With Stochastic Demand Based On Partial Trade Credit

Capital is the first impetus for a firm to carry out business activities,as well as one of the biggest problems firms face with in their development.Trade credit helps a firm solve funds restriction because of delay payment.In practice,the supplier usually requires that the retailer pay for the partial amount of the purchased items immediately when ordering and the account for the rest of the purchased items can be settled at the end of trade credit period.This is socalled partial trade credit.Trade credit with down payment could be regarded as partial trade credit.Partial trade credit not only helps the downstream firm alleviate the financial difficulty,but also can increase the upstream firm's sales and avoid financial risks caused by trade credit to some extent.Hence,partial trade credit has been widely used in the reality.Scholars both at home and abroad are paying the growing attention to the theoretical analysis of this trading behavior.After investigating the practice of partial trade credit and some related results deduced recently for trade credit in supply chain optimization,the purpose of this dissertation is to analyze the operation decision of supply chain members.The research in this paper extends and improves the content of the inventory management theory and method,which has certain actual application value.The main work and innovations of the dissertation are summarized as follows:(1)Retailer's single-period inventory and payment model with partial trade credit.We consider the ordering and payment issues for a retailer facing stochastic demand.We assume that the retailer can enjoy the partial trade credit from his supplier and borrow money from bank as well if needed,and he can also earn return by investing his superfluous on-hand cash(if any).The retailer's objective is to maximize the expected cash level at the end of the selling period.We formulate the model of this problem by taking initial inventory and capital levels as the two-dimensional state.First,given the exogenous fraction of immediate payment,we show that unlike the critical fractile solution the retailer's optimal ordering strategy is a twothreshold policy,which is independent of the retailer's initial inventory level and capital level.Second,we consider an extensive model where the fraction of immediate payment is decided by the retailer.The extensive problem is a two-variable optimization problem.We employ the sequential optimization procedure to reduce the two-variable problem to an optimization problem over a single variable,and present the structure of the retailer's optimal policies under different partial-trade-credit penalty rates.Interestingly,we show that: 1)if the fraction of immediate payment is exogenous,both partial trade credit and loan opportunity are detrimental to the capital-constrained retailer in many cases,although they can stimulate the retailer to order more in general.Moreover,when the retailer doesn't lack initial capital,the financing opportunity like partial trade credit and loan may lead to conservative ordering decision.2)Facing with imperfect information about retailer's initial working capital,suppliers can design an appropriate trade credit interest rate to elicit information on retailer's cash status if the fraction of immediate payment is decided by the retailers.(2)Supplier's optimal policy of newsvendor-type product under partial trade credit.This dissertation consider a supply chain with a supplier and a retailer: a capital-limited retailer who sells a newsvendor-type product to the market.In the presence of partial trade credit,we model their strategic interaction as a Stackelberg game with the supplier as the leader to maximize the supplier's expected terminal cash.We present the structure of the supplier's optimal policy under the scenarios of both given and decided fraction of payment fraction when ordering.Two transformation play important role in the analysis of the model.The first is to transform the two-dimensional area into a one dimensional range,and on the basis of the transformation,we present the retailer's optimal ordering response under different capital levels.The second transformation is to employ the retailer's one-to-one map between order quantity and wholesale price to transform the wholesale price into equivalent order quantity,for the supplier's joint wholesale price and order payment proportion decision.(3)Retailer's dynamic inventory control model with stochastic demand and partial trade credit.In inventory management theory,periodic review stochastic inventory system is an important research object.This dissertation consider two kinds of products,one remains the same value in the whole sales phase,another is called perishable product,whose value remains a constant only in a fixed period of validity,and when more than the period of validity,cost is needed to dispose the remaining products.In this dissertation,stochastic dynamic inventory models are developed for the two kinds of products respectively where in each model a retailer periodically purchases a product from a supplier and sells it to a market with random demand.The objective is to maximize the retailer's expected terminal cash at the end of the planning horizon.The existence and uniqueness of the optimal polices are proved for given initial capital and inventory level and the critical-number policy is presented for the last period.We also show an interesting phenomena that the optimal order-up-to level is in general not monotone in initial capital except for the last period.For the last period,it is always optimal for the retailer to order more when he has more capital;however,when there are several remaining periods,under certain circumstances,it can be optimal for the retailer to order less.(4)Joint inventory and financing decision for multi-product with partial trade credit.Multiproduct inventory problem is an important research subject in logistics and supply chain management,which is also a problem of firms,especially for capital-constraint ones to decide how to allocate funds to order different products.Therefore,we consider a supply chain with a supplier and a retailer: a capital-limited retailer who sells two products from the supplier to satisfy the market.In the presence of partial trade credit,we first develop retailer's inventory model to maximize his expected terminal cash,and present the structure of the retailer's optimal order quantity and the allocation of the fund,and show the effect of demand fluctuations on capital allocation proportion of two products.Then,for supplier's problem,we employ numerical experiments to investigate the effect of demand fluctuations and retailer's bankrupt cost on the supplier's profit in the presence of retailer's bankrupt cost.We also present the retailer's optimal order policy and the supplier's optimal payment proportion in the absence of retailer's bankrupt cost.We show an interesting phenomena that the optimal order quantity decreases with the increase of retailer's initial capital under certain circumstances.The main reason is that the joint effect of partial trade credit and bankruptcy can transfer part of demand uncertainty to the supplier.The less initial capital the retailer owns,the bigger the bankrupt threshold will be,which leads to higher bankruptcy risk and more effective uncertainty-transfer.However,when order quantity rises to certain level,the bankruptcy threshold decreases with the increase of initial capital,and the uncertainty transferred through bankruptcy and partial trade credit decreases.Therefore,it can be optimal for the retailer to order less to reduce risks.