finite sets无穷集合和有穷集合finiteadj.有限的finite-time exergoeconomic performance有限时间火用经济性能finite singular transformation semigroup有限奇异变换半群finite element strength reduction method有限元强度折减法finite element mesh generation technique有限元网格生成技术finite-difference time-domain method时域有限差分法finite-element modal updating technique有限元修正技术Finite-difference time-domain methods时域有限差分finite difference beam propagation method有限差分光束传播法finite difference frequency domain method频域有限差分法finite difference of non-uniform meshes非等距差分