The inversion of gravity data by using hybrid encoding ge netic algorithm
求解位场反演问题的混合编码遗传算法

Genetic algorithm has some advantages in solving the inversion problems of complex non linear geophysical equation. Its multi point searching is able to find the global optimal solution, avoiding falling into a local optimum. The searching efficiency of genetic algorithm largely depends on encoding mechanism. Standard genetic algorithm (SGA) can not make search effective, because the crossover and mutation do not get most effectively searching in either binary or decimal encoding mechanism. The operation of crossover in binary encoding mechanism may produce more new individuals. On the other hand, decimal encoding mechanism makes the operation of mutation have larger searching range to find solutions. This paper gives the comparison of the searching capabilities of mutation operators in binary and decimal, and presents a hybrid encoding genetic algorithm (HEGA) mechanism. The method is based on hybrid encoding in genetic procedure, in which, the mutation operation is executed in decimal code and other operations in binary code. It actually introduces the two encoding mechanisms into genetic algorithm procession and has the mutation operated with high probability. HEGA may solve the inversions of complex non linear geophysical equations. In this paper, the inversions of synthetic 2D models and an observed gravity anomaly by using HEGA are shown.