“…They obtained the response to the initial conditions using the method of D'Alembert. Chen et al [9][10][11] investigated a reflected wave superposition method, which was proposed for a finite axially traveling string with classical and nonclassical boundaries at the two ends, and analyzed the total mechanical energy as well as its time rate of change. Huang et al [12] investigated the dynamic responses of high-dimensional nonlinear models of a fixed-fixed translating beam, and analyzed continuous energy exchange and the beating waveform phenomenon of high-dimensional models.…”