Water Effects on the First-Order Transition in a Model of Earthquakes

Dongmo, M. W.; Kagho, L.Y.; Pelap, F. B.; Tanekou, G. B.; Makenne, Y. L.; Fomethe, A.

doi:10.1155/2014/160378

Cited by 11 publications

(4 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It should be noted that all our numerical simulations are performed using MATLAB/SIMULINK. Other software such as C++, Fortran, or Python could also be used [40][41][42][43][44]. Blocks 3, 4, and 5 allow us to always work at the maximum power point.…”

Section: Methodsmentioning

confidence: 99%

Photovoltaic Systems Based on Average Current Mode Control: Dynamical Analysis and Chaos Suppression by Using a Non-Adaptive Feedback Outer Loop Controller

et al. 2023

View full text Add to dashboard Cite

This paper deals with the modeling and theoretical study of an average-current-mode-controlled photovoltaic power conversion chain. It should be noted that current mode control is a superior scheme for controlling DC–DC power electronic converters for photovoltaic applications. Bifurcation diagrams, largest Lyapunov exponents, Floquet theory, and time series are used to study the dynamics of the system. The theoretical results show the existence of subharmonic oscillations and period-1 oscillations in the system. The results of the numerical simulations showed that when the battery voltage at the output of the converter is fixed and ramp amplitude is taken as a control parameter, the photovoltaic power system exhibits the phenomenon of period doubling leading to chaotic dynamics. Furthermore, bifurcation diagrams showed that both the critical value of ramp amplitude for the occurrence of border collision bifurcation and the critical value of ramp amplitude for the occurrence of period-1 in the proposed system increased with the value of the battery terminal voltage. The numerical results are in accordance with the theoretical ones. Finally, an external control based on a non-adaptive controller having a sinusoidal function as a target is applied to the overall system for the suppression of chaotic behavior.

show abstract

Section: Methodsmentioning

confidence: 99%

Photovoltaic Systems Based on Average Current Mode Control: Dynamical Analysis and Chaos Suppression by Using a Non-Adaptive Feedback Outer Loop Controller

et al. 2023

View full text Add to dashboard Cite

show abstract

“…is developed in the linear approximation in terms of the Taylor series according to Langer and Tang [31] as follows:…”

Section: First-order Approximate Analytical Solutionmentioning

confidence: 99%

Delayed and fractional-order dynamics of a model for earthquake induced by stress perturbations

Bisong,

Mofor,

Fomekong

et al. 2024

Phys. Scr.

View full text Add to dashboard Cite

Fractional calculus and time delay provide a powerful tool to model complex systems with memory, fractal systems and viscoelastic systems. Earthquakes are both complex systems with long-memory and some of their faults have fractal properties and, the rocks constituting faults have viscoelastic behavior. In this paper, we examined the dynamics of the spring-block considering the fractional viscous damping force and interaction between the blocks. The shear stress response is studied using the harmonic balance method and the numerical simulations are performed through Adams-Bashforth-Moulton scheme. The effects of the fractional-order and time delay on the amplitude-frequency curves and on the transition between steady state and seismic regime are investigated. The system response shows the existence of the resonance and anti-resonance. It appears that the resonance amplitude and resonance frequency are strongly dependent on the time delay and fractional-order. This resonance phenomenon results in an accumulation of energy which can lead to the destabilization of the fault system. At the anti-resonance the system response has minimum amplitude, and the blocks move without accumulated energy. The results show that the delay and fractional viscous can affect the properties of the rock, which is characterized by the modified linear stiffness coefficient, modified linear damping coefficient and the modified linear friction coefficient. The stability and hopf bifurcation are investigated and the critical value of the time delay for the occurrence of Hopf bifurcation is determined. The transition from stationary state to the periodic orbit and vice-versa through the hopf bifurcation is observed in the system.

show abstract

“…Since we are dealing with nonlinear differential equations, a large number of numerical solution methods can be used, for example using software such as PYTHON, FORTRAN, C++ etc [57][58][59][60][61]. In this work, the curves are obtained using the Runge-Kutta method of order 4.…”

Section: Sa Av Pf mentioning

confidence: 99%

On the heart rhythm analysis using a nonlinear dynamics perspective: analytical study and electronic simulation

Fonkou,

Kengne,

Wamba

et al. 2024

Phys. Scr.

View full text Add to dashboard Cite

Biological systems are highly complex, so understanding them requires extensive analysis. Cardiac rhythms are one such analysis. These rhythms are linked to a complex dynamic system defined on the basis of the electrical activity of cardiac cells. This electrical activity is essential to human physiology, defining numerous behaviours that include normal or pathological rhythms, generally measured by the electrocardiogram (ECG). This article presents a mathematical model to describe the electrical activity of the heart, using a nonlinear dynamics perspective. The stability analysis of this model in its autonomous state, uni-directionally coupled, shows a very rich dynamical behaviour characterized by periodical regions of stability and unstability. The model studied makes it possible to construct synthetic ECGs. These ECGs demonstrate a variety of responses, including normal and pathological rhythms: ventricular flutter, ventricular fibrillation, ventricular tachycardia and ventricular extrasystole. A quantitative analysis of the model is also carried out using bifurcation diagrams and the corresponding maximum Lyapunov exponents. In addition, variations in sinus rhythm are described by a time-dependent frequency (a dynamic variable varying in a disordered manner or following a given law), representing transient disturbances. This type of situation can represent transitions between different pathological behaviours or between normal and pathological physiologies. In this respect, the perspective of nonlinear dynamics is used to describe cardiac rhythms, which makes it possible to represent normal or pathological behaviours. An electronic simulation performed with the OrCAD-Pspice software for a real implementation of the cardiac system is carried out. The results obtained are in agreement with those obtained numerically.

show abstract

Water Effects on the First-Order Transition in a Model of Earthquakes

Cited by 11 publications

References 16 publications

Photovoltaic Systems Based on Average Current Mode Control: Dynamical Analysis and Chaos Suppression by Using a Non-Adaptive Feedback Outer Loop Controller

Photovoltaic Systems Based on Average Current Mode Control: Dynamical Analysis and Chaos Suppression by Using a Non-Adaptive Feedback Outer Loop Controller

Delayed and fractional-order dynamics of a model for earthquake induced by stress perturbations

On the heart rhythm analysis using a nonlinear dynamics perspective: analytical study and electronic simulation

Contact Info

Product

Resources

About