短語詞組短語beam in vibration 梁振動beam type vibration frequency 梁型振動頻率beam vibration theory 梁振動理論beam vibration equations 梁的振動方程beam -plate vibration 自由振動solving beam vibration equations 解梁振動方程nonlinear beam vibration equations 非線性梁振動方程beam vibration equation 梁橫振動方程beam vibration eigenfunctions 梁振動特征函數(shù) 返回 beam vibration