In this study we quantify and interpret the inherent memory in fractional-order capacitors when subjected to constant current charging/discharging waveforms. This is done via a finite difference approximation of the fractional order rate equation I(t) = Cαdαv(t)/dtα (0 le; α ≤ 1) relating current to voltage in these devices. It is found that as the fractional exponent α decreases, the weight of the voltage memory trace that results from the contribution of past voltage activity increases, and thus the measured response of the device at any time is increasingly correlated to its past. Ideal

A novel scheme suitable for the emulation of fractional-order capacitors and inductors of any order less than 2 is presented in this work. Classically, fractional-order impedances are characterized in the frequency domain by a fractional-order Laplacian of the form s± α with an order 0 < α< 1. The ideal inductor and capacitor correspond, respectively, to setting α= ± 1. In the range 1 < α< 2 , fractional-order impedances can still be obtained before turning into a Frequency- Dependent Negative Resistor (FDNR) at α= ± 2. Here, we propose an electronically tunable fractional-order impedance

In this letter, a third-order wideband voltage-mode all-pass filter (APF) is proposed for application as a true time delay (TTD) cell. The advantages of designing a single-stage higher order filter over cascading several lower order stages are illustrated. The proposed APF circuit is based on a single metal-oxide-semiconductor (MOS) transistor and is canonical because it requires one resistor, one inductor, and two capacitors. To the best of the authors' knowledge, this is the first single-transistor third-order APF circuit to be reported in the literature. The operation of the proposed APF is

This paper presents a generalization, attractor control and multi-scroll generation method for fractional-order chaotic systems through rotation transformation. A novel synchronization-dependent colored image encryption and secure communication scheme is also proposed. The systems with dynamic rotation angle fit successfully in a generalized dynamic switched synchronization scheme. Dynamic control switches specify whether the system acts as a master or slave. Dynamic scaling factors determine whether the master is a single system or a combination of two or more systems. Simulation results

This paper proposes an efficient encryption technique based on Dynamic and Secure Substitution Box (DS2B) design suitable for IoT and resource-constrained platforms. The DS2B has the advantages of simple structure and good encryption performance. A different number of strong S-boxes could be generated with minor variations in the DS2B parameters. Performance analyses of the DS2B, including differential/linear cryptanalysis, bijective, nonlinearity, strict avalanche criterion (SAC), and bit independence criterion (BIC) have been presented where high nonlinearity , and low differential

The main goal of this work is to exploit different tools in order to approximate a general double exponent fractional-order transfer function. Through the appropriate selection of the two fractional orders of this function, different types of filters can be derived. The investigated approximation tools are either curve fitting based tools or the Padé approximation tool, and the derived approximated transfer functions in all cases have the form of rational integer-order polynomials, which can be easily realized electronically. © 2020, Springer Science+Business Media, LLC, part of Springer

This paper presents the modelling and control of a 2-DOFs Twin rotor multi input multi output (MIMO) system which is a laboratory setup resembling the dynamics of a helicopter. In this paper, the system modelling process is done using the common conventional mathematical model based on Euler-Lagrange method. The transfer functions of the model are used in the different tuning methods to reach the optimal PID gain values. The study uses conventional Proportional-Integral (PI) and Proportional-Integral-Derivative (PID) controllers to obtain a robust controller for the system. Particle Swarm

This article presents the parametric analysis of the optical microring resonator. It includes the numerically simulated analysis. The mathematical formulation represents the several relations that could influence the performance of optical microring resonator. The simulations give the graphical representations of ring resonator performances by the alteration of various parameters. In this paper, we have analyzed the variations in quality factor, extinction ratio and the resonance peak of an optical microring resonator with changes in effective refractive index, length of the ring and the group

the proposed paper aims to design and model an air levitation system, which is a highly nonlinear system because of its fast dynamics and low damping. The system is trained using a Nonlinear Autoregressive model with exogenous input (NARX model). An enhanced height measurement system, modified setup, and several training techniques have been used to overcome the restrictions that the non-linearity of the system imposes in the literature. The system mathematical model has been illustrated, followed by an identified model using NARX model trained on several input-output data from the physical

In this paper, a new scheme for the realization of an optical logic circuit using Mach–Zehnder modulators (MZM) with direct detection has been proposed. Amplitude and phase information of the optical signals have been used for the differentiation of optical signals into four different states that can be represented using two binary inputs, while direct detection has been used for the effective mapping of these states with their respective binary outputs. The realization of seven logic gates, two reversible optical logic gates (Feynman and double Feynman gates) and half adder and half