...Venkatanarayanan Ramakrishnan; Brian F. Feeny This work concerns the response of a damped Mathieu equation with hard cyclic excitation at the same frequency as the parametric excitation. A second-order perturbation analysis using the method of multiple scales unfolds resonances and stability...

...Venkatanarayanan Ramakrishnan; Brian F. Feeny The present study deals with the response of a damped Mathieu equation with hard constant external loading. A second-order perturbation analysis using the method of multiple scales (MMS) unfolds resonances and stability. Non-resonant and low-frequency...

... on the time required to compute the resonant frequencies of nonproportionally damped linear systems. It is shown that, for degrees-of-freedom greater than or equal to nine, the dual-oscillator approach is significantly faster (on average) than the conventional approach, and that the relative computation speed...

... perturbations or random disturbances to infer the approach of a critical speed (resonance). Such disturbances, that may be based on intentional probing, or simply the result of naturally occurring fluctuations, cause small transients. It is the changing nature of these transients (as characterized...

..., such as subsea fishing, accumulator replacements are challenging. In-line dampeners provide a straightforward solution but have never been designed to cater for resonance dampening as such. Commercially developed in-line dampeners also have nitrogen-filled bladders or act like and behave as accumulators, posing...

... for the response of the system with five different boundary conditions are illustrated. Traditional excited static strings show nodes when resonance occurs. However, it is found in this study that the static nodes of axially moving strings appear under arbitrary frequency even far away from resonance...

...Ashu Sharma The dynamics of parametrically excited systems are characterized by distinct types of resonances including parametric, combination, and internal. Existing resonance conditions for these instability phenomena involve natural frequencies and thus are valid when the amplitude...

... is discussed. An optimal distance between window and thin film is successfully derived and used in some practical examples. Resonance takes place for a suitable input frequency, and thus such transducers can be used to either generate acoustic waves of specific frequency or to filter specific resonant...

... in a very slender continuous rotor. When the rotor is supported horizontally, the difference in support stiffness and the asymmetrical nonlinearity appear as a result of shifting from the equilibrium position. By the influences of the internal resonance and the initial axial force, the nonlinear resonance...

... developed yet. In the previous paper, the authors proposed a simple method by utilizing discontinuous spring characteristics, which can suppress steady-state resonances. This paper shows that this method is also effective to suppress unstable vibrations. By using this method, the unstable vibrations can...

.... Because the rotor is slender, the natural frequency p f n of a forward whirling mode and p b n of a backward whirling mode have the relation of internal resonance p f n : p b n = 1 : ( − 1 ) . Due to the influence of the internal resonance, various phenomena occur, such as Hopf bifurcation, an almost...

... frequencies and mode shapes for the linear problem are found. The correction terms are obtained from the last order of expansion. Nonlinear frequencies are calculated and then amplitude and phase modulation figures are presented for different forcing and damping cases. The 3:1 internal resonances...

... components. The extent of the mitigation varies for different excitation frequency ranges. The critical amplitude of the dry friction torque beyond which the system operates with a locked arm is determined analytically. Superharmonic resonances are observed in the responses of the generalized span...

...Mark H. Holdhusen; Kenneth A. Cunefare A state-switched absorber (SSA) is a device that is capable of switching between discrete stiffnesses; thus, it is able to instantaneously switch between resonance frequencies. The state-switched absorber is essentially a passive vibration absorber between...

...Tsuyoshi Inoue; Yukio Ishida Rotating machinery has effects of gyroscopic moments, but most of them are small. Then, many kinds of rotor systems satisfy the relation of 1 to ( − 1 ) type internal resonance approximately. In this paper, the dynamic characteristics of nonlinear phenomena, especially...

... frequency of a forward-whirling mode p f > 0 and that of a backward-whirling mode p b < 0 have the relation of internal resonance p f : p b = 1 : − 1 . Recently, many researchers analyzed nonlinear phenomena by using the Jeffcott rotor with nonlinear elements. However, they did not take this internal...

...D. F. Shi; W. J. Wang; L. S. Qu In order to overcome the shortcomings in the traditional envelope analysis in which manually specifying a resonant frequency band is required, a new approach based on the fusion of the wavelet transform and envelope spectrum is proposed for detecting and localizing...

... . Manuscript received September 2002; Revised April 2003. Associate Editor: K. Grosh. 01 September 2002 01 April 2003 30 07 2004 gyroscopes nonlinear dynamical systems vibrations micromechanical devices resonance The boundary conditions on micromachined beams...

..., in essence, as a nonlinear energy sink (NES). Energy pumping is caused by 1:1 resonance captures on resonant manifolds of the damped systems. We show that the NES is capable of absorbing significant portions of the energies generated by transient, broadband external excitations. By performing a series...

... conditions are derived considering the static friction of the rotating motion at the supporting point (pivot) of the pendulum. It is theoretically shown that the static friction at the pivot of the pendulum plays a dominant role in the suppression of parametric resonance. The boundary conditions...