The step by step approximation method can be used to the new phase segment,however,the mixed phase segment can only be solved by .
纯新相段可用逐步近似法,混合相段则必须用数值方法求解。
Under certain conditions,these systems are proved by mean value method and successive approximation method to have almost periodic solutions.
研究具有两个时间变量的概周期微分方程系的概周期解的存在性问题,在某些条件下,利用平均值法和逐步逼近法证明了这类方程系具有概周期解。