“…So far, researchers have proposed the exact wave-based vibration approach for analyzing beams and better simplifying the vibration analysis of such structures [ 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. Based on the influence of discontinues and planar frame structure, especially on bending and longitudinal vibration, the further interpretation concerning the raised approach is shown by Mei [ 29 , 30 ], which greatly simplifies analysis of the vibration properties of planar frames.…”