基于双曲正切函数改进蚁群算法的冷链物流配送路径优化

Optimization of Cold Chain Logistics Distribution Routing Based on Improved Ant Colony Algorithm with Hyperbolic Tangent Function

为研究冷链物流配送路径优化问题,考虑客户需求量、车辆最大承载量和客户时间窗要求等影响因素,构建了一个以油耗成本、惩罚成本等综合配送成本最小为目标函数的数学优化模型。针对原始蚁群算法收敛速度较慢、容易陷入局部最优等问题,设计了一种基于双曲正切函数改进的蚁群算法。将变参数思想引入蚁群算法,利用双曲正切函数实现算法在迭代过程中自动调整参数。首先,构建由配送中心与多个目标客户组成的冷链物流运输模型;其次,由于蚁群算法优化性能受启发式因子、信息素挥发率等关键参数影响,采用双曲正切函数改进蚁群算法的参数设计;最后,通过考虑和不考虑时间窗情形下的模拟实例进行仿真试验,验证模型和算法的有效性。通过与原始蚁群算法对比分析,证明了基于双曲正切函数改进的蚁群算法性能更加优越。结果表明:改进后的蚁群算法既保持了迭代初期优秀的全局搜索能力,又可以在迭代末期实现快速收敛。利用基于双曲正切函数改进的蚁群算法可以有效地解决冷链物流配送路径优化问题,对企业实现经济与环保双赢局面具有重要的现实意义。

With the continuous expansion of fresh market demand,cold chain logistics has become an important part of modern logistics.In order to study the distribution routing optimization problem of cold chain logistics,considering the influence of customer demand,maximum vehicle carrying capacity and customer time window requirements,a mathematical optimization model is constructed to minimize the comprehensive distribution cost,such as fuel consumption cost and penalty cost.An improved ant colony algorithm based on hyperbolic tangent function is designed to solve the problem that the original ant colony algorithm is slow in convergence and easy to fall into local optimum.The idea of variable parameters is introduced into ant colony algorithm.The hyperbolic tangent function is used to automatically adjust the parameters in the iterative process.First,a cold chain logistics transportation model composed of distribution centers and multiple target customers is constructed.Second,due to the optimization performance of ant colony algorithm is affected by heuristic factors,pheromone volatilization rate and other key parameters,hyperbolic tangent function is used to improve the parameter design of ant colony algorithm.Finally,the effectiveness of the model and algorithm is verified by simulation experiments with and without considering the time window.Comparing with the original ant colony algorithm,it is proved that the improved ant colony algorithm based on hyperbolic tangent function has better performance.The result shows that the improved ant colony algorithm not only maintains the excellent global search ability at the beginning of iteration,but also achieves fast convergence at the end of iteration.Ant colony algorithm based on hyperbolic tangent function can effectively solve the problem of cold chain logistics distribution routing optimization,that has important practical significance for enterprises to achieve a win-win situation of economy and environment pretection.