This work presents a hybrid (experimental-computational) application for improving the vibration behavior of structural components using a lightweight multilayer composite. The vibration behavior of a flat steel plate has been improved by the gluing of a lightweight composite formed by a core of polyurethane foam and two paper mats placed on its faces. This composite enables the natural frequen...

In machine systems where a rotor spins within a finite clearance space supported by bearings, contact between the rotor and its surround can result in persistent coupled vibration of the rotor and stator. When the vibration response is driven predominantly by friction forces, rotordynamic stability becomes a serious issue. This paper introduces a theory for model-based verification of dynamic s...

This paper aims to investigate the train-induced ground vibration and appropriate countermeasures using numerical modeling by Abaqus. First, the effect of appropriate boundary modeling in wave propagation studies is addressed by illustrating the application of nonreflecting boundaries in Abaqus using infinite elements. Second, the propagation of waves in the ground was investigated by applying ...

The changing of certain types of energy into other types in machines and mechanisms, the transformation of movement forms and carrying out certain working processes inevitably causes the emergence of variable forces and vibration-causing momentum. Vibration control and management are important tasks in aerospace field. This thesis solves the problem of the development of an effective control sy...

Vibrations are usually undesired phenomena as they may cause discomfort, disturbance, damage, and sometimes destruction of machines and structures. It must be reduced or controlled or eliminated. One of the most common methods of vibration control is the dynamic absorber. In this paper, the non-linear dynamics of a two-degree-of freedom vibration system including quadratic and cubic non-lineari...

To reduce engine vibration, a semi-active controlled magnetorheological suspension is designed. First, the magnetic circuit of new simulated. Furthermore, non-parametric forward and inverse dynamic models with Elman neural network are established, where modeling results accuracy analyzed. Second, according to characteristics vibration control suspension, an improved fruit fly optimized proporti...

In this study, we consider the vibration mitigation problem for a structural system using a magneto-rheological (MR) damper. For this purpose, through the use of Lyapunov-based design techniques, a nonlinear adaptive controller which can compensate the parametric uncertainties related to both the structural system and the MR damper has been constructed. To overcome effects of the unmeasurable i...

The response of the microchip solid-state Nd:YAG laser, which is subjected to external frequency-shifted feedback, is experimentally and theoretically analysed. The continuous weak response of the laser to the phase and amplitude of the feedback light is achieved by controlling the feedback power level, and this system can be used to achieve contact-free measurement of displacement, vibration, ...

The classical time-frequency distributions represent timeand frequency-localized energy. However, it is not an easy task to analyze multiple signals that have been simultaneously collected. In this paper, a new concept of non-parametric detection and classification of the signals is proposed using the mutual information measures in the time-frequency domain. The time-frequency-based self and mu...

Nanoelectromechanical resonator sensors based on graphene sheets (GS) show ultrahigh sensitivity to vibration. However, many factors such as the layer number and dimension of the GSs will affect the sensor characteristics. In this study, an analytical model is proposed to investigate the vibration behavior of double-layered graphene sheets (DLGSs) with attached nanoparticles. Based on nonlocal ...