The amplitude curves

This paper investigates the nonlinear vibration of saturated porous functionally graded plate subjected to the combination of mechanical and thermal loadings. Three different distributions of porosity are considered. Based on the Biot and higher order shear deformation theories, the vibration characteristics including natural frequency, deflection amplitude – time curves and relation between frequency ratio and amplitude of the saturated porous plate are determined.

13p viambani 18-06-2024 3 1   Download

This paper studies the class of on-off damping controller, which switches the damping level from high to low and back at fixed times every quarter of period. Among this class, this paper shows the solution of the lower bound controller producing the lowest amplitude-frequency curve. The lower bound curve shows some fundamental natures of the system and gives some useful directions for a good on-off damping controller.

9p nguaconbaynhay11 07-04-2021 14 1   Download

In this paper, the continuous stiffness measurement (CSM) indentation is employed to investigate fatigue mechanical properties of structural steel under cyclic loading. For this purpose, several representative analytical approaches were introduced to estimate the basic mechanical properties including Young’s modulus and indentation hardness from the characteristics of the loading/unloading curves.

11p cothumenhmong8 04-11-2020 16 2   Download

Fatigue curve presents the relation between stress (mean stress, maximum stress or stress amplitude) and the number of stress cycles till a machine element is completely broken. This curve is served as the important basis of design as well as lifetime prediction for machine elements. In order to create a fatigue curve, the traditional fatigue test method is applied to specimens using a cyclic stress with constant amplitude.

10p angicungduoc5 13-06-2020 13 0   Download

In nonlinear systems, the first order of smallness terms of nonresonance forced and parametric excitations have no effect on the oscillation in the first approximation. However, they do interact one with another in the second approximation.

12p chikychiky 01-11-2018 26 0   Download

In the theory of nonlinear oscillations, in order to identify the resonance curve we usually try to eliminate the dephase in the equations of stationary oscillations. We obtain thus a certain frequency-amplitude relationship.

9p chikychiky 27-10-2018 34 0   Download

The nonlinear vibration of a pendulum whose support undergoes arbitrary rectilinear harmonic motion is studied. The main attention is paid to the resonant cases and the stationary vibrations. The resonant conditions are explained. The amplitude - frequency curves are plotted for various values of parameters and the stability of vibration is investigated. The rotating motion of the pendulum and its stability are also considered.

9p thienthanquydu 21-10-2018 17 1   Download