Alireza Moradi, Alireza Shaterzadeh^*

CMC-Computers, Materials & Continua, Vol.82, No.1, pp. 223-257, 2025, DOI:10.32604/cmc.2024.059441 - 03 January 2025

Abstract For the first time, the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work. The plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to it. For this purpose, the partial differential equations of motion have been derived based on the first-order shear deformation theory, employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain relations. Then, the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation… More >

Y. A. Amer¹, A. T. El-Sayed², M. N. Abd El-Salam^3,*

Sound & Vibration, Vol.54, No.3, pp. 149-161, 2020, DOI:10.32604/sv.2020.08469 - 31 August 2020

Abstract In this paper, we used time delay feedback to minimize the vibrations of a hybrid Rayleigh–van der Pol–Duffing oscillator. This system is a one-degree-offreedom containing the cubic and fifth nonlinear terms and an external force. We applied the multiple scales method to get the solution from first approximation. Graphically and numerically, we studied the system before and after adding time delay feedback at the primary resonance case (Ω ≌ ω). We used MATLAB program to simulate the efficacy of different parameters and the time delay on the main system. More >