中文摘要：

针对改进型Duffing混沌系统检测微弱信号,求解Lyapunov阈值时间过长问题,提出二分法实现快速求解Duffing系统由混沌到周期态的阈值。首先,以0.1步长的Lyapunov指数确定一个粗略的阈值;然后根据对分法快速收索DuffingHolmes振子混沌阈值的精确值,这一算法大大提高了阈值搜索速度,通过识别微弱信号仿真事例证明这种方法的有效性。

英文摘要：

In the improved Duffing system,detection signal is quite weak,hence,solving the chaos threshold takes a lot of time when one applies Lyapunov exponent criterion. The paper proposes a bisection algorithm to solve the problem.The algorithm can figure out the threshold value whcih makes Duffing system transfer from chaos state to period state.First,we take 0. 1 as the step length to find a threshold roughly based on the Lyapunov exponent. Then the bisection algorithm figures out the exact value for the threshold. The speed of calculating is speeded a lot,Simulation result proves the validity of this method.