The association coefficient was taken for the similar degree of amphibians in every two zoogeographical zones.The cluster analysis was taken by group average method. 建立物种有无分布的二元数据列联表，利用联合系数表示每两个地理小区内两栖动物的相似程度，以类平均法进行了聚类分析。
A Small signal model set up through the aid of state space average method can do a world of good for Conducting high frequency Switching Power supply stable analysis. 推证出用状态空间平均法建立小信号模型对高频开关电源进行稳定性分析的方法。
