Study On Vehicle Routing Robust Optimization For Hazardous Materials Transportation

Hazardous materials transportation vehicles routing optimization is one of the basic links to ensure the safety of hazardous materials transportation. Due to the safety requirements of hazardous materials transportation, the risk factors must be considered, so hazardous materials transportation vehicles routing optimization problem is a multi-objective optimization problem, and it has a certain complexity. If we want to find one or more valid paths with the smallest risk, time, or some other attribute values in the hazardous materials transportation network, the corresponding data information needs to be known in each section. However, due to the uncertainty of some data, some hazardous materials transportation routes are also uncertain, sometimes when an attribute value has subtle changes on the road, the obtained hazardous materials transportation routes are also likely to be unacceptable. Therefore, in the uncertain environment, to design the scientific and reasonable hazardous materials transportation vehicle routing considering the factors such as transportation risk and transportation and find a stronger robustness vehicle routing are very important for hazardous materials transportation.This paper researches on the hazardous materials transportation vehicles routing problem. Through analysis the problem can be divided into 4 sub-problems, i.e., single distribution center single vehicle distribution routing problem for hazardous materials transportation, single distribution center multi-vehicle distribution routing problem for hazardous materials transportation, multi-distribution center single vehicle distribution routing problem for hazardous materials transportation and multi-distribution center multi-vehicle distribution routing problem for hazardous materials transportation, then respectively established adjustable robustness multi-objective Bertsimas robust optimization model for hazardous materials transportation route under the uncertain environment. For hazardous materials transportation route multi-objective robust model of single distribution center with single vehicle transportation, we design a multi-objective partheno-genetic algorithm which adopts banker method to structure non-dominant individuals and uses gathering distance to keep distribution of evolve population to solve it; for hazardous materials transportation route multi-objective robust model of single distribution center with multi-vehicle transportation, an improved multi-objective genetic algorithm is given to solve it; for hazardous materials transportation route multi-objective robust model of multi-distribution center with single vehicle transportation, we design a "two stage method" to solve the model, first we find customer need points served by distribution center through the global search clustering method in the first stage, and then use multi-objective partheno-genetic algorithm to solve each distribution center in the second stage; for hazardous materials transportation route multi-objective robust model of multi-distribution center with multi-vehicle transportation, we design a hybrid multi-objective genetic algorithm to solve it which takes multiple distribution centers and multi-customer need points into account. Finally, an example is given for each sub-problem in every section, and the designed algorithm is used to solve the example. we can find Pareto solutions set with different robust for hazardous materials transportation vehicle routings by using the designed algorithm, and the result can provide certain reference value for decision makers to find out one or more relatively robust hazardous materials transportation routes.