液化天然气库存路径问题建模与算法  

Model and Algorithm for Inventory Routing Problem of Liquified Natural Gas

作　　者：巫威眺[1] 王殿雷 马昌喜[2] WU Wei-tiao;WANG Dian-lei;MA Chang-xi(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,Guangdong,China;School of Traffic and Transportation,Lanzhou Jiaotong University,Lanzhou 730070,Gansu,China)

机构地区：[1]华南理工大学土木与交通学院,广东广州510641 [2]兰州交通大学交通运输学院,甘肃兰州730070

出　　处：《中国公路学报》2022年第11期252-270,共19页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(72071079,52272310,71861023)。

摘　　要：考虑液化天然气(LNG)的在途挥发、转移挥发与库存挥发对配送成本与风险的影响,根据LNG风险特性采用蒸汽爆炸模型量化库存和运输风险,并针对传统单因素风险评估方法的不足,结合多源数据(兴趣点密度、土地生产总值产出率和人口密度)构建多因素复合风险评估指标反映事故严重程度的空间异质性,建立库存路径问题双目标优化模型,实现多周期LNG库存和配送方案的联合优化。根据问题的特征,设计基于贪婪策略预优化并结合变邻域搜索(VNS)的多目标粒子群(MOPSO)混合优化算法,且通过标准测试函数对改进前后的MOPSO算法和非支配遗传算法(NSGA-Ⅱ)进行比较;与NSGA-Ⅱ相比,MOPSO在结合VNS前后分别具有32%和42%的收敛性优势,结合VNS混合优化相比原始MOPSO有15%的收敛性优势。最后,以广州地区LNG加气站供应体系进行案例分析。研究结果表明:库存与运输成本存在利益背反关系,且在短暂缺货时总成本较低;忽略挥发的影响会导致小批量频繁补货,从而增加不必要的运输成本;LNG挥发成本占总成本的10%~20%,库存挥发率对成本影响较大,但对风险影响很小,当库存挥发率低于2%时投资降低挥发率带来的经济效益较大,当超过2%时,投入产出比迅速降低;风险限值约束对路径选择和成本影响较大,20%风险限值的降低带来了10%总成本的提高,但20%风险限值的提高仅降低5%的总成本,说明总成本在逐步接近不考虑风险时的最低值,存在优化上限。In this study, we considered the impact of in-transit, transfer, and inventory volatilization of liquefied natural gas(LNG) on distribution costs and risks. According to the risk characteristics of LNG, a steam explosion model was adopted to quantify the inventory and transportation risks. To overcome the drawbacks of traditional single-factor risk assessment methods, we developed a multi-factor compound risk assessment index combining multi-source data(point of interest density, gross domestic product output rate, and population density) to capture the spatial heterogeneity of accidents. In this study, a two-objective optimization model of the inventory routing problem was developed to jointly optimize the multi-period LNG inventory and distribution schemes. Based on the characteristics of the problem, a hybrid optimization algorithm of multi-objective particle swarm optimization(MOPSO) based on greedy strategy pre-optimization and integration of variable neighborhood search(VNS) was designed. The MOPSO algorithm and NSGA-Ⅱ(non-dominated sorting genetic algorithm II) algorithm were tested using the standard test functions. Compared to NSGA-Ⅱ, MOPSO shows a convergence advantage of 32% before combining VNS, which increases to 42% when VNS is combined. Combining the VNS hybrid optimization also leads to a 15% convergence advantage over the original MOPSO. Finally, the case analysis of the LNG filling station supply system in Guangzhou shows the existence of a trade-off between the inventory and transportation costs;when there is a short-term shortage, the total cost is lower. Neglecting volatilization leads to frequent small-volume replenishment, which increases unnecessary transportation costs. The cost of LNG volatilization accounts for 10%-20% of the total cost. The inventory volatilization rate has a significant impact on the cost but has little impact on the risk. When the inventory volatilization rate is lower than 2%, the economic benefit, brought by the investment reduction in the volatilization rate,

关 键 词：交通工程 LNG 混合优化算法 危险品运输管理 多因素风险评估 库存路径问题 

分 类 号：U491.11[交通运输工程—交通运输规划与管理]