Research On Model And Algorithm For Economic Lot Scheduling Problem With Shelf Life Product

Economic Lot Scheduling Problem (ELSP) is the production scheduling problem that a single facility manufactured multiple products in order to minimize the total cost of production. Products with shelf life have a strong timeliness in custody and will bring additional cost for deterioration. In most of previous literature on ELSP with shelf life product, it is assumed that the production satisfied customer's demand, orders are not allowed in arrears, and the system is perfect. Common cycle approach is used to construct model. As a matter of fact, shortage is inevitable. Facility may also be partly damaged by the long-term use, and time-varying lot size approach costs lower. So these factors should be considered in the research on ELSP with shelf life product.Firstly, ELSP model with shelf life product under the condition of shortage is considered. Time-varying lot size approach is used to solve the problem. Shortage is allowed when the stock time is more than the shelf life. The model of expecting total cost per unit time with shortage is constructed. A Changed sequence searching heuristic algorithm is used to solve the model. Finally a numerical example is also provided to illustrate the problem.Secondly, ELSP model with shelf life product under imperfected production system is considered. Time-varying lot size approach is used to solve the problem. The model of expecting total cost per unit time with periodic review is constructed. In the beginning, we producted at the demand speed. When the idle time is used up, we produced at the maximum speed. A new algorithm is used to solve the production cycle. Improved Dobson heuristic algorithm is used to solve the procuction sequence. Lastly the feasibility and validity of the model and algorithm is illustrated by using simulation data.Finally, the development of a production management system is introduced. The production decision of ELSP with shelf life product under the condition of shortage is used to verify the theoretical results. The feasibility and application value of ELSP model with shelf life product is displayed fully.