In this study, the vibration behavior of functional graded (FG) circular and annular nanoplate embedded in a Visco-Pasternak foundation and coupled with temperature change is studied. The effect of in-plane pre-load and temperature change are investigated on the vibration frequencies of FG circular and annular nanoplate. To obtain the vibration frequencies of the FG circular and annular nanopla...

In this paper, a new and simple approach for the vibration control of flexible spacecrafts during the attitude maneuvering is proposed. Our control strategy integrates the command input shaping and Reference Model Variable Structure Output Feedback Control (RMVSOFC) techniques. In this method, the input shaper is implemented outside of the feedback loop to achieve the exact elimination of the r...

In this paper a high order sliding manifold control approach is adopted as a technique to effectively reduce the vibrations of a metal rectangular panel. A novel theoretical result for an output feedback control law is presented to show how the singular perturbation theory can be used to tackle the problem of active vibration control. In this paper we address the problem of reducing vibration o...

The rolling element bearing is a key part in many mechanical facilities and the diagnosis of its faults is very important in the field of predictive maintenance. Till date, the resonant demodulation technique (envelope analysis) has been widely exploited in practice. In complex machines, the vibration generated by a component is easily affected by the vibration of other components or is corrupt...

A simple model presented here is to study the thermal effect on vibration of non-homogeneous orthotropic visco-elastic rectangular plate of parabolically varying thickness having clamped boundary conditions on all the four edges. For non-homogeneity of the plate material, density is assumed to vary linearly in one direction. Using the separation of variables method, the governing differential e...

THE TECHNIQUE OF DETERMINATION OF STRUCTURAL PARAMETERS FROM FORCED VIBRATION TESTING Wai Fan Tsang This thesis details the results of an investigation into a technique for determination of "useful" structural parameters from forced vibration testing. The implementation of this technique to full scale civil engineering structures was achieved by several developments in the experimental and comp...

Certain diseases produce changes in the elastic properties of soft tissues. Conventional imaging modalities in some cases have poor performance in diagnosing these types of diseases. To overcome this problem, elastographic imaging techniques that focus on evaluating the elastic properties of tissues, i.e., tissue stiffness, have been developed in the past three decades. Soft tissues, however, i...

The vibration signatures of a normally aspirated diesel engine contain valuable information on the health of the combustion chamber components. It could be used to detect incipient faults in the engine. Several commonly occurring faults were induced in a 4-stroke diesel engine and the ensuing vibration signals recorded. Three diierent feature extraction techniques: Domain expertise, wavelet ana...

For an induction machine, we suggest a theoretical development of the mechanical unbalance effect on the analytical expressions of radial vibration and stator current. Related spectra are described and characteristic defect frequencies are determined. Moreover, the stray flux expressions are developed for both axial and radial sensor coil positions and a substitute diagnosis technique is propos...

Modern electronics, computers, and software have made it possible to greatly improve the testing of optical components and optical systems and the resulting improvements in the new optical instruments and devices we use are evident. Until recently a major limitation of interferometry for precision metrology was the sensitivity to the environment. In recent years many techniques for performing h...