In order to conduct research on order allocation of multi-period multi-product purchase with stochastic demand and price discount,a multi-objective mixed integer stochastic programming model is formulated.

Research on vendor selection & order quantity allocation problem under multi-product purchases;

Based on the reverse logistics theory,this paper focuses on inventory control of the multi-cyclical products,provides the strategy of the optimal order quantity for retailers who adopt fixed-interval system when the demand is a random variable.

Realizing product multi-life-cycle depending on remanufacturing engineering may maximally recovers added-valueembodied in worn product and decreases environment pollution, also remanufactures product which reprogressive would be ob-tained.

This paper introduces the background of product multi-lifecycle engineering and analyses its basic connotation,upon which its theoretical foundation,the main technical fields,the research situations at home and abroad,and developing tendency are discussed and introduced.