We consider traveling wave solutions to a class of diierential-diierence equations. Our interest is in understanding propagation failure, directional dependence due to the discrete Laplacian, and the relationship between traveling wave solutions of the spatially continuous and spatially discrete limits of this equation. The diierential-diierence equations that we study include damped and undamp...

A special nonlinear fuzzy controller is presented to control the output signal of an undamped one-degree-of-freedom oscillating system with nonlinear characteristic. Basically, this controller consists of a feedback part and a feed-forward part. Whereas the feedback part is made up by a classical fuzzy controller, the feed-forward part is based on a fuzzy model taking into account the nonlinear...

The slow passage problem through a resonance is considered. As a model problem, we consider a damped harmonically-forced oscillator whose forcing frequency is slowly ramped linearly in time. The set-up is similar to the familiar slow passage through a Hopf bifurcation problem, where for slow variations of the control parameter, oscillations are delayed until the parameter has exceeded the criti...

the current paper focuses on some analytical techniques to solve the non-linear duffing oscillator with large nonlinearity. four different methods have been applied for solution of the equation of motion; the variational iteration method, he’s parameter expanding method, parameterized perturbation method, and the homotopy perturbation method. the results reveal that approximation obtained by th...

in this study, a new efficient semi-analytical method is introduced to give approximate solutions of strongly nonlinear oscillators. the proposed method is based on combination of two different methods, the multi-step homotopy analysis method and spectral method, called the multi-step spectral homotopy analysis method (msham). in this method, firstly, we propose a new spectral homotopy analysis...

in this paper, solution of nonlinear optimal control problems and the controlled duffing oscillator, as a special class of optimal control problems, are considered and an efficient algorithm is proposed. this algorithm is based on state parametrization as a polynomial with unknown coefficients. by this method, the control and state variables can be approximated as a function of time. also, the ...

in this paper a new form of the homptopy perturbation method is used for solving oscillator differential equation, which yields the maclaurin series of the exact solution. nonlinear vibration problems and differential equation oscillations have crucial importance in all areas of science and engineering. these equations equip a significant mathematical model for dynamical systems. the accuracy o...

A simple relaxation oscillator is designed by directly coupling a RC timing network to a passive S-shaped current-controlled nonlinear resistor and is then modified for chaos. The resulting chaotic oscillator inherits the main features of the relaxation oscillator, which are its low-power consumption and low-voltage operation from single or dual power supplies. These features are attributed to ...

As the wind power generation develops, the Doubly Fed Induction Generator (DFIG) based wind power system may suffer Sub Synchronous Resonance (SSR) and High Frequency Resonance (HFR) in the series and parallel compensated weak network. The principle and frequency of HFR have been discussed using the Bode diagram as an analysis tool. However, the HFR can be categorized into two different types: ...

The strong stabilizability of linear second order equation is investigated in this paper. It supposed that there exists a feedback law makes the origin closed-loop system globally asymptotically stable. Then control subject to cone-bounded nonlinearity. Well-posedness and stability results under such (nonlinear) are stated. first result proven by using nonlinear semigroups techniques Schauder f...