Research On Ordering And Production Strategy Contains Imperfect Products

Product ordering decisions and inventory management play an important part in the production and operation of enterprises. Enterprises often encounter decision problems of economic order quantities such as how much does each batch order or how many ordering times a year is the most economic and reasonable. In the ordinary analysis of economic order quantities, there are two necessary assumptions:one is the no limit warehouse capacity of enterprise and the other is all the products are qualified products. However, in the reality, the two assumptions are not practical. The warehouse capacity of enterprise is always limited and the products may include certain defective products for not checked before leaving assembly line and damaged in the process of loading, transportation and warehousing. These defective products also called imperfect products whose quality, performance and appearance are substandard. The products which are not perfect can be sold in a form of "substandard goods" or "defective goods" and dealers should tell consumers what aspects they have flaws. To some extent, the imperfect products have substitution effect of perfect products for its high performance and price ratios. On this basis, the thesis researches a ordering and inventory management model considering the substitutability of products.In recent years, the study of diversified products、alternative products and other studies related to ordering and inventory have become a hot issue of many scholars and experts at home and abroad and a hot issue of supply chain and ordering inventory management in the theory research and practice. Most theses are based on the typical newsboy problem、single-period problem or the further studies. The paper will inherit the idea and take the single-period problem as the basic direction and add the specific alternative of perfect products and imperfect products. It will research from the following aspects:Firstly, in the supply chain which only has distributors, there are two kinds of products when distributors are ordering. In order to prevent the market conflicts, distributors put the two products into different markets for sale. This is the one-way alternative situation which has the certain alternative costs and alternative rate. On this basis, the optimal ordering strategies are put forward on the situation of facing certain market demands. Secondly, in the supply chain which only has distributors, two different products exist in the ordering products, namely perfect products and imperfect products. Imperfect products can partly replace the perfect products. The rate of substitution relate to the price, the perfect degree of products. And these will influence the consumer demand. In this case, it proves the existence of optimal ordering quantity and optimal price. It also proves that the price difference should be limited in a certain range; otherwise the total profits will decline.Thirdly, based on the research of EOQ model, the EPQ model with fuzzy deteriorating production process and allowable shortage is investigated. Based on the credibility theory, the total cost per unit time function with shortage cost and fuzzy rework cost is derived. Some properties of the total cost function are revealed. The optimal production run length which can minimize the expected total cost per unit time is proved to exist and be unique. The upper and lower bounds of the optimal production run length are determined. Finally, numerical examples are presented to illustrate the effects of the rework cost and the percentage of the defective items on the optimal production policy.Furthermore, all conclusions of this thesis have been given the practical management meaning. At the end of the thesis, the summary and outlook are maken.