基于模块化仿真的共享汽车联合调度优化

运营商在调度车辆时单独采用员工或顾客调度策略均难以有效解决共享汽车分布不均衡导致的盈利难问题.为此，在传统时空网络基础上，考虑道路拥堵和用车需求随时间变化对运营的影响，基于C#语言和O2DES(object-oriented discrete event simulation)离散事件仿真框架，建立由模块化站点和路段模型组成、可高效率运行的共享汽车仿真系统；在此基础上，提出一个以运营商日均净收益最大化为目标，联合决策车辆库存量阈值和行程定价的仿真优化模型，并为解决随机环境下的全局优化问题，设计了EGA-OCBA (elitist genetic algorithm with optimal computing budget allocation)算法；最后，以成都市的5个共享汽车站点为例，验证了仿真优化模型的有效性.仿真优化结果表明：在相同车队规模下，与采用固定价格的顾客调度策略相比，联合策略可使日均净收益提升10.37%～162.30%；与单独的员工调度策略相比，联合策略可使日均净收益提升15.34%.

Optimization for Joint Relocation of Carsharing Based on Modular Simulation

It is difficult for operators to effectively solve the profitable difficulty caused by the imbalanced distribution of shared vehicles when considering staff-based and customer-based relocation alone. Thus, based on the traditional space-time network, the impact of time-varying road congestion and trip demands on the operation is considered. Based on C# language and O2DES (object-oriented discrete event simulation) framework, an efficient carsharing system model composed of modular station and road segment models is built. Moreover, a simulation-optimization model that jointly determines vehicle inventory thresholds and trip pricing is proposed to maximize the daily net revenue of operators. In order to solve the global optimization problem in a random environment, an elitist genetic algorithm (EGA) with optimal computing budget allocation (OCBA) is designed. Finally, a case study in Chengdu with five sites is conducted to demonstrate the efficiency of the proposed simulation-optimization model. The results show that with the same fleet size, the optimal design can increase the average daily net revenue by 10.37%?162.30% compared with customer-based relocation (fixed pricing); the optimized scheme can increase the profit by 15.34% compared with separate staff-based relocation.