说明：  将铁路视为周期结构，通过声子晶体的传递矩阵法，计算的钢轨的横波和纵波的色散曲线。两程序分别将钢轨视为欧拉梁和Timoshenko梁。
(Regarding the railway as a periodic structure, the dispersion curves of the transverse and longitudinal waves of the rail are calculated by the transfer matrix method of phononic crystals.The two programs regard the rails as Euler beams and Timoshenko beams, respectively.)