快捷货运服务网络设计研究综述

服务网络设计是快捷货运运营管理层面的重要内容，也是交通运输领域的关键科学问题。本文分析了快捷货运服务网络设计的内涵，并从研究内容、优化模型、求解算法这3个方面对国内外相关研究现状展开详细论述。在研究内容上，对不同运输方式和多式联运进行归类总结，单一运输方式下和综合运输体系下的快捷货运服务网络设计都涵盖了路径规划、流量分配、时刻优化等方面，且内涵和外延都在不断拓展。在模型构建上，有基于节点-弧和基于路径两种角度的建模方式，其中，基于时空网络角度建模成为近年动态服务网络模型设计的重要方向；建模的背景以确定条件为主，不确定条件下的模型大多仅是考虑需求的不确定，并未揭示出各种不确定性参数对网络结构和流量分配的影响机制；所考虑的因素从初期的需求总量、服务成本、服务频率，逐渐增加能力约束、时刻影响、设备利用等方面。在求解算法上，以启发式算法为主，其中，大多基于智能算法，随着计算机运算效率的提高及商业求解软件功能的强大，基于列生成和基于模型松弛或分解的算法在近年呈上升趋势。最后，结合快捷货运内外部条件的变化，提出快捷货运服务网络设计在考虑低碳因素、不确定条件、演化机理等方面有待进一步研究的方向。

Review of Service Network Design for Express Freight Transportation

Service network design is an important content of express freight operation management, and as well as a key scientific problem in the field of transportation. In this paper, the connotation of service network design for express freight is analyzed firstly, and then, the state of the art is discussed in detail from research content, optimization models, and solution algorithms. In terms of research content, different transport modes and multimode transport are classified and summarized, the service network design of express freight covers path planning, flow distribution, and scheduling optimization under either a single transport mode environment or integrated transportation system. Meanwhile, the connotation and extension of the research contents are constantly expanding. In the aspect of model construction, there are node-arc formulation and path formulation, and the space-time network has been widely used in dynamic service network model design in recent years. The considered modeling background is mainly based on deterministic conditions, while most models under uncertain conditions only consider the uncertainty of demand, and do not reveal the influence mechanism of various uncertain parameters on network structure and flow distribution. The factors considered include the total demand volume, service cost, service frequency in the initial stage, and gradually increasing capacity constraints, time impact, equipment utilization, et al. Heuristic algorithm is the main solution method, and there are many methods based on intelligent algorithms. With the improvement of computer operation efficiency and the powerful function of commercial software, the proportion of algorithms based on column generation and model relaxation or decomposition is on the rise in recent years. Finally, combined with the changes of internal and external conditions of express freight, the further research direction of express freight service network design in the aspects of considering uncertain conditions, low-carbon factors, and evolution mechanism is discussed.