A study of the combined helicopter noise and vibration problem was conducted. A refined aerodynamic model capable of calculating the unsteady surface pressure distribution on rotor blade/flap combinations is developed and coupled with an aeroelastic analysis simulation code. An acoustic prediction tool based on WOPWOP is combined with the aeroelastic analysis based on a flexible blade with coup...

This paper discusses a detailed study carried out on vibration characteristics of transversely loaded pultruted composite beams. A considerable discrepancy was noticed in the measured vibration of the transversely loaded beam and the calculated natural frequencies of the beam using Euler-Bernoulli beam theory. It has been observed that the natural frequencies of the beam were increased after la...

Micro-cantilevers are frequently used as scanning probes and sensors in micro-electromechanical systems (MEMS). Usually micro-cantilever based sensors operate by detecting changes in cantilever vibration modes (e.g., bending or torsional vibration frequency) or surface stresses when a target analyte is adsorbed on the surface. The catalyst for chemical reactions (i.e., for a specific analyte) c...

Directing at the problem of torsional vibration occurred in the start-up procedures of long shaft drive transmission existed in printing equipment, we raised a variable structure control method based on Variable parameters fuzzy. The method not only displays feature of traditional non-linear variable structure control like nondeference derivation, planning the dynamic process and good capacity ...

Article history: Received: 27.6.2015. Received in revised form: 26.11.2015. Accepted: 1.12.2015. This paper presents experimental and numerical study with the objective of exploring the effect of suction control on vortex-induced vibration (VIV) of a bridge deck. The vertical and torsional responses of the model with or without suction control during this experiment were measured. The results d...

The association of internuclear ophthalmoplegia (INO) with torsional nystagmus is rare. We report the case of a 63-year-old man presenting with sudden onset of diplopia. On ocular examination, he had left INO and a torsional nystagmus with counter-clockwise quick-phases from the patient's point of view in the primary position, ipsiversive to the side of the medical longitudinal fasciculus (MLF)...

in this paper a new element for analysis of thin-walled structures is presented, and the effects of secondary shear stresses on longitudinal displacements are examined. since the interpolation functions are based on non-uniform torsional differential equations, the analysis of stiffness matrix is facilitated. therefore, its ability to produce accurate results with the least number of elements i...