ANALYTICAL EXPRESSION OF TRANSITION BOUNDARIES OF THE SOLUTION OF DUFFING SYSTEMS
Duffing系统解的转迁集的解析表达式

The nonlinear Duffing equation is studied and fold boundaries of period T are obtained by introducing Burton's and Cheung's results and nonlinear frequency. Also, the transition boundaries of symmetric breaking are obtained by general Newton's method. Our results are in good agreement with Leung's by IHB method,and we overcome the difficulty of great quantities of computation by computer.