Research On The Economic Lot Scheduling Problem With Stochastic Demand

According to the seller's market change into the buyer's market, the customer's demand has become increasingly diversified, personalized, and customer's demand has become more random. The stochastic demand is a serious challenge for production system that it is difficult to schedule production plans. At the same time diversifications of production demand require enterprises to invest in flexible production systems to reduce setup time and setup cost. So research on how economic and reasonable scheduling to minimize the cost of production to meet the random demand under the changes the flexible and do not change the flexible of production have great significance.In this paper, first summed up the domestic and international research current situation of the economic lot scheduling problem, focusing on random customer demand, and then innovative propose the method of resolving the economic lot size scheduling problem under the both case that consider the setup cost and do not consider the setup cost. Specific researches of this article are as follows:(1) In this paper, based on review the economic lot and economic lot size scheduling theory and literature. Understand the economic lot size scheduling problem, as well as the research background and what the problem want to solve. On this basis, expounded the starting point for this paper and the problems want to solve.(2) Under don't consider the setup costs circumstances, use of the time-varying lot sizes method build based on stochastic demand scheduling economic lot size model, the model is based on the average cost of a minimum target, at the same time given a model algorithm to solve variables, and compared with the lower bound cost model and the common-cycle cost model. Analysis by the numerical calculation:in the same conditions, the cost of the time-varying lot sizes method to solve the stochastic economic lot scheduling problem close to the cost of the lower bound and lower than the cost of common cycle approach.(3) Consider enterprise invest to improve production systems and then reduce the setup cost. The setup cost reduction has some influences in reducing the production lot sizes, the production cycle. This paper establish the stochastic economic lot scheduling problem that the target of minimum sum of capital investment, inventory costs, and setup cost minimum cost and the capital investment and the year production frequency as the variable. On the basis, we give an algorithm to solve the scheduling economic lot size model, and to count the variables. By numerical analysis showed that:Compared with the setup cost unchanged, the economic lot scheduling approach with considering reduction setup cost reduce the total cost, increase production frequency, reduce the lot sizes of production. Study shows that under certain conditions, enterprises improve production systems can receive good economic benefits.In this paper, economic lot size scheduling as study object, give full consideration of the actual variety circumstances in enterprises production, and to give a solution to solve the scheduling problem. In this paper, the results of research have a certain degree of guidance to determine the production lot sizes and production sequence.