finite sets无穷集合和有穷集合finiteadj.有限的finite/infinite element coupling method有限形无限元耦合方法Finite-length Y-shaped carbon nanotube有限长Y型碳纳米管finite -difference time -domain method时域有限差分法finite simple groups classification theorem单群分类定理finite-difference time-domain algorithm时域有限差分法finite simulation element analysis software有限元仿真分析软件finite-difference frequency domain method频域有限差分finite element-boundary element eou piing耦合算法finite-difference frequency-domain method频域有限差分（FDFD）方法finite differential strength reduction method有限差分法