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Both China Railway Express (CRE) companies and international liner companies are faced with the problem of empty container repositioning. In order to reduce empty container repositioning cost and realize their sustainable development, this paper studies the optimization problem of empty container repositioning under the condition of their cooperation. To minimize the cost, three optimization models of empty container repositioning are established, which are based on the single repositioning and cooperative repositioning. Numerical experiments are carried out to analyze the three empty container repositioning optimization models solved by CPLEX. The results show that the total cost could be greatly reduced by the cooperative repositioning. The effects of cooperation become more obvious with the unit storage cost or repositioning cost increases and become weaker with the unit mutual rental cost increase. When the demand fluctuation is in a certain range, the cooperation is still effective, which can reduce the cost. But when it is beyond a certain range, the benefits will be greatly reduced. In reality,for the sustainability of their cooperation, both sides should pay attention to the proportion of supply and demand and set reasonable mutual rental cost.

In order to reduce the total cost of empty container repositioning, a multi-period empty container repositioning optimization model of the China Railway Express was established by using distributed robust chance-constrained programming based on partial information such as mean and variance of demand. This established model considered sea-land intermodal transportation, uncertain empty container demand and foldable containers. To simplify the model, the distributed robust chance constraints were transformed into equivalent ones that could be easily solved, and the empty container demands were determined. Numerical experiments were carried out to analyze the influence of different parameters on the total cost. The results showed that the total cost could be greatly reduced by sea-land intermodal transportation. Using foldable containers could reduce the total cost of empty container repositioning. With the improvement of service level, the numbers of empty container repositioning increased owing to the distributional robust chance constraints. When standard and foldable containers were used simultaneously, the total cost could be greatly reduced by appropriately using foldable containers under three different supply–demand relationships of containers. The optimization results may provide a greatly feasible reference for the decision makers of the China Railway Express.

Because demand for processed food products is uncertain, the processors face dilemma to satisfy their customers. The processors are unable to sell their products if demand turns out to be low. That is, some of the products will expire, the producer would have been better off by producing less. But if the processors choose to produce less to ensure that the entire products are sold, there will be an excess of demand if demand turns out to be high. In this case the processors would have been better off by choosing to produce large quantity. The dilemma is more experienced by SMEs food processors because they lack enough capital to acquire advanced technologies to assist in decision making. In this paper an attempt has been made to address the coordinating effects of ABD program in managing demand uncertainty. Fruits and vegetables drying factory has been focused as a case study. Theoretical expressions supported by explanatory mathematical equations have been offered. It is noted that the processor may achieve better decisions and managed demand uncertainty once they agree upon information sharing.

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