| With the rapid development of ro-ro transportation,the traditional terminal handling operation mode based on manual experience has been difficult to adapt to the increasingly largescale and professional ro-ro terminal handling operation.How to ensure that the ro-ro terminal improves the transportation efficiency of ro-ro ships on the basis of existing facilities is becoming a research hotspot.In this paper,a mathematical model is established for the stowage problem of ro-ro ships,and a stowage algorithm of ro-ro ships based on species selection genetics is designed.The constraint theory is used to optimize the vehicle loading and unloading operation of ro-ro terminals,and a prototype system for optimizing the loading and unloading operation of ro-ro terminals is designed.The whole process simulation and optimization from stowage to loading and unloading are realized.The specific work of this paper is as follows:Firstly,the research status of ro-ro ship loading problem and terminal loading and unloading operation problem is introduced.Based on the analysis of ro-ro ship terminal loading and unloading operation process,loading requirements and vehicle loading and unloading process,combined with the shortcomings of existing research on ro-ro ship terminal loading and unloading problem,the overall research framework of ro-ro ship loading problem and roro terminal vehicle loading and unloading operation optimization problem studied in this paper is designed.Secondly,in order to solve the problem of ro-ro ship stowage,a mathematical model of ro-ro ship stowage is established,and a stowage algorithm based on species selection genetics is designed to solve the stowage problem.The genetic algorithm based on species selection is used as the main framework,and the linear programming algorithm is used to generate the initial population.Three fitness functions of relative value density,relative space utilization rate and maximum horizontal line height ratio were designed to evaluate the stowage scheme,and the crossover and mutation were optimized according to the population division.The case comparison analysis is carried out for the sensitivity and superiority of the parameters,and the reasonable use range and superiority of the algorithm parameters are determined.Thirdly,in order to improve the efficiency of ro-ro terminal handling operations,based on the five-step theory of constraint theory,an optimization strategy for ro-ro terminal handling operations based on constraint theory is designed to identify the bottleneck factors that limit the production efficiency of the terminal.According to the characteristics of bottleneck factors related to personnel and standards,the improved A*algorithm and the dispatching sequence generation algorithm are integrated to estimate the vehicle dispatching time,and the ro-ro terminal handling operations are optimized from the perspective of improving bottlenecks and obeying bottlenecks.Finally,on the basis of the above research,the prototype system of ro-ro ship stowage and terminal loading and unloading operation optimization is designed,and the whole process optimization from stowage to loading and unloading is realized.The system is used to solve the problem,and the results are compared with the standard genetic algorithm loading case and vehicle loading and unloading case respectively,which verifies the effectiveness and feasibility of the loading algorithm and the optimization strategy of wharf loading and unloading operation. |
