“第三方代管”参与下的共享单车回收路线优化问题

以共享单车回收为背景，研究了“第三方代管”参与下的回收路线优化问题。针对代管员和调度卡车的特征，提出激励代管员将零散分布的损坏单车运送至附近的中转点，然后派遣卡车将这些集中起来的损坏单车从中转点运送至维修中心。以总成本最小为目标建立混合整数规划模型，针对问题特性设计改进遗传算法。数值实验论证了问题特性，并论证得出在所提回收策略下及时回收损坏单车，不仅可以减轻公共空间被损坏单车挤占的问题，还可以有效减少回收成本。实验结果还表明所设计算法在短时间内能获得高质量解。

A Bike Recycling Problem with Third-party Participation in Bike Sharing Systems

In bike sharing systems, broken bikes may be piled up as high as a mountain in many stations due to the lack of recycling. Therefore, the recycling problem of broken bikes is significant to develop a sustainable bike sharing system. To improve the recycling efficiency of broken bikes, a bike recycling routing optimization problem with third-party managementis proposed. Based on the characteristics of third-party employees and trucks, third-party employees are incentivized to relocate broken bikes to transshipment stations to facilitate centralized recycling, while trucks are deployed to transport these broken bikes from transshipment stations to the repair center. The problem is formulated as a mixed-integer programming model to minimize the total cost. To solve the proposed problem, an improved genetic algorithm is developed. Numerical experiments demonstrate the characteristics of the proposed problem, and reveal that the proposed recycling strategy can solve the problem of public space occupied by broken bikes and effectively reduce the operation cost. Numerical experiments also illustrate that the proposed solution method can obtain high-quality solutions within a short computation time.