回收物流设施多层选址模型及其算法

针对废弃物品的收集、预处理和再制造问题，建立了回收物流设施选址混合整数规划（MILP）模型，用分枝定界法求解，为提高分枝定界法的收敛速度、减少运算量，先用遗传算法为MILP找到较好的可行解，以其对应的目标函数值为分枝界定法上界，从而可以在分枝界定法的搜索中剪去大量分枝．用算例证明了算法的有效性和可行性．

Facility Location Model for Multi-level Returned Logistics and Its Algorithm

A facility location model for multi-level returned logistics was proposed to study the issuesof collection, preprocessing and remanufacture of end-of-life products. This model is a mixed integerlinear program (MILP), and is solved with a branch and bound (B&B) algorithm. To make B&Bfaster in convergence and less in calculation, a genetic algorithm is used to obtain a reasonably goodresolution at the beginning of B&B. The objective value corresponding to the resolution is taken as theupper bound of B&B to prune a large number of branches from the searching tree. An example waspresented to verify the effectiveness and feasibility of the proposed method.