Optimizing Empty Container Allocation Based On Hybrid Genetic Algorithm

The imbalance of economy's development results in the unbalance of trade flow that caused serious imbalance between the supply and demand of empty containers.So, there are a great deal of empty containers have to be allocated and disposed which account for 20 percent of the whole containers in transportation per year.In the various operating costs of a shipping company,container management cost has become the second largest cost only inferior to the cost of ports fee.At the same time,empty container allocation cost and container leasing cost which are highly related to the empty container allocation account for more than half of the container management cost. As a result,it's very central for every shipping company to organize the flow of empty container effectively and raise the efficiency of empty container allocation.Genetic algorithm(GA) is a random global search and optimization method that imitate the evolutional process of the natural creature,which based on the theories of Darwin's evolutionism and Mendelian's heredity.In essence,GA is an efficient,parallel and global search method that could automatically obtain and accumulate relevant knowledge of search space during the search process.Recently,it shows significant theory and practical value in function optimization,artificial intelligence,fuzzy control and so on.However,it has drawbacks like premature phenomena,weakness of local search ability etc.In contrast,traditional optimization algorithms such as steepest descent method are easy to literately exploit the optimal solutions around the existing candidate solutions,which have powerful local search capability.Thus,bringing the steepest descent method to GA could make up the low local search ability of genetic algorithm.In this paper,the hybrid genetic algorithm(HGA) is applied to solve the modified optimization problem.Firstly,the workflow of empty container allocation in shipping lines is analyzed and constituted as two parts,planning the empty container allocation assignments and transiting enough empty containers to the leaving ports in the assignments.So,focusing on the latter part firstly,the shipping container allocation model is established,seeking the minimization of the total cost for empty containers in a certain time.Then,an integer code hybrid genetic algorithm combining with the steepest descent method is proposed to solve the optimal problem.Finally,the simulation results show that the improved hybrid genetic algorithm more effectively finds the global optimal solution than the conventional genetic algorithm.The method is capable of resolving the problem and has good performance to find the best container allocation strategy.It has some guiding value for the shipping companies' empty container allocation management.