Chaos In New Polynomial Discrete Logistic Maps With Fractional Derivative And Applications For Text Encryption

In this paper, we propose new polynomial discrete logistic equations based on the classical logistic map, which exhibit chaotic behavior as control parameters vary. We also explore versions with fractional derivatives. Using the chaotic sequence generated by these equations, we develop an encryption scheme for text. The scheme relies on initial conditions, control parameters, and a transformation of text characters into values between 0 and 1, followed by a transformation to discrete chaotic values for transmissio

Analysis of the nonlinear dynamics of a single pendulum driven by a magnetic field using the magnetic charges interaction model and the experimentally fitted interaction model

In this work, we analyzed theoretically and experimentally the nonlinear dynamics of a magnetic pendulum driven by a coil-magnet interaction. The force between the magnetic elements and the resulting torque on the pendulum are derived using both the magnetic charges interaction model and the experimentally fitted interaction model. This enables the comparison between the two models. The current in the coil is taken first as a sinusoidal current and then as a square current. The comparison of the structure of each interaction model is conducted and it appears that they give qualitatively similar characteristics. The harmonic balance method is used to approximate the frequency responses of the pendulum leading to both symmetric and asymmetric or one-side (intrawell) oscillations. The two-parameters bifurcation diagrams are plotted showing the different dynamical behaviors considering the current amplitude and frequency as the control parameters. Good agreements are found between our theoretical results and experimental ones.Comment: Article published in the journal Mechanical Systems and Signal Processing. It consists of 18 page

Secondary frequency control stabilising voltage dynamics

The ongoing energy transition challenges the stability of the electrical power system. Stable operation of the electrical power grid requires both the voltage (amplitude) and the frequency to stay within operational bounds. While much research has focused on frequency dynamics and stability, the voltage dynamics has been neglected. Here, we study frequency and voltage stability in the case of simple networks via linear stability and bulk analysis. In particular, our linear stability analysis of the network shows that the frequency secondary control guarantees the stability of a particular electric network. Even more interesting, while we only consider secondary frequency control, we observe a stabilizing effect on the voltage dynamics, especially in our numerical bulk analysis.Comment: 10 pages, 7 figure

Quantum associative memory with improved distributed queries

The paper proposes an improved quantum associative algorithm with distributed query based on model proposed by Ezhov et al. We introduce two modifications of the query that optimized data retrieval of correct multi-patterns simultaneously for any rate of the number of the recognition pattern on the total patterns. Simulation results are given.Comment: 16 pages, 10 figures, submitted to Int J Theor Phy

Effects of asymmetry, transmission delay and noises on the stability of an elementary electricity network

We numerically study the effects of the asymmetry of the transmission lines capabilities, of the transmission delay and power noises, on the stability of an elementary electricity network consisting of one machine and two generators. It is found that the asymmetry increases the stability of the system. It is also found that the threshold value of the perturbation intensity leading to the network instability decreases as the time delay increases. When the system is subject to a stochastic perturbation, its stability depends not only on the noises intensity, but also on the time delay and the value of the transmission lines capabilities

Analysis of an electrostatic energy harvester with variable area, permittivity and radius

This paper reports on an electrostatic vibration energy harvester (e-VEH) system with variable area, variable permittivity, and variable radius. Nonlinear oscillator equations are established for each case, and solved analytically and numerically. The power produced by each configuration of the harvester is presented in terms of resistive load, frequency and external excitation