Yazar "Rajagopal, Karthikeyan" için listeleme
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CHAOTIC CUTTLESH: KING OF CAMOUAGE WITH SELF-EXCITED AND HIDDEN FLOWS, ITS FRACTIONAL-ORDER FORM AND COMMUNICATION DESIGNS WITH FRACTIONAL FORM
Rajagopal, Karthikeyan; Çiçek, Serdar; Akgül, Akif; Jafari, Sajad; Karthikeyan, Anitha (Amer Inst Mathematical Sciences-Aims, 2020)There are many works on self-excited and hidden attractors. However the relationship between them is less investigated. In this study we present a system which can have both hidden self-excited attractors. Dynamical ... -
Chaotic Oscillations in a Fractional-Order Circuit with a Josephson Junction Resonator and Its Synchronization Using Fuzzy Sliding Mode Control
Ramakrishnan, Balamurali; Cimen, Murat Erhan; Akgul, Akif; Li, Chunbiao; Rajagopal, Karthikeyan; Kor, Hakan (Hindawi Ltd, 2022)A linear resistive capacitive inductive shunted model of a Josephson junction with a topologically nontrivial behaviour is considered in this paper. We have considered a fractional-order flux-controlled memristor to ... -
Complete analysis and engineering applications of a megastable nonlinear oscillator
Jahanshahi, Hadi; Rajagopal, Karthikeyan; Akgül, Akif; Sarı, Naeimeh Najafizadeh; Namazi, Hamidreza; Jafari, Sajad (Pergamon-Elsevier Science Ltd, 2018)In this paper, we investigate some unrevealed features of a newly introduced megastable chaotic oscillator. This oscillator has a rich dynamical behavior including limit cycle, torus and strange attractor. Also it has ... -
Control, synchronization with linear quadratic regulator method and FFANN-based PRNG application on FPGA of a novel chaotic system
Koyuncu, İsmail; Rajagopal, Karthikeyan; Alçın, Murat; Karthikeyan, Anitha; Tuna, Murat; Varan, Metin (Springer Heidelberg, 2021)In this work, LQR method is proposed for controlling and synchronizing newly developed chaotic system. The developed 4-D chaotic system has been investigated via time series, phase portraits and bifurcation diagrams. ... -
Dynamical analysis, sliding mode synchronization of a fractional-order memristor Hopfield neural network with parameter uncertainties and its non-fractional-order FPGA implementation
Rajagopal, Karthikeyan; Tuna, Murat; Karthikeyan, Anitha; Koyuncu, İsmail; Duraisamy, Prakash; Akgül, Akif (Springer Heidelberg, 2019)Recent developments in the applications of neural networks in various engineering and technology applications have motivated researchers to study the nonlinear behavior of such networks. In this work we investigate a ... -
Dynamical investigation and chaotic associated behaviors of memristor Chua's circuit with a non-ideal voltage-controlled memristor and its application to voice encryption
Rajagopal, Karthikeyan; Kaçar, Sezgin; Wei, Zhouchao; Duraisamy, Prakash; Kifle, Teweldbrhan; Karthikeyan, Anitha (Elsevier Gmbh, 2019)In this paper we modified the conventional Chua's circuit with a non-ideal voltage-controlled memristor with a quadratic internal state. Dynamical behaviors of Modified Memristor based Chua's Circuit (MMCC) are investigated ... -
An exponential jerk system, its fractional-order form with dynamical analysis and engineering application
Rajagopal, Karthikeyan; Akgül, Akif; Jafari, Sajad; Karthikeyan, Anitha; Çavuşoğlu, Ünal; Kaçar, Sezgin (Springer, 2020)A simple jerk system with only one exponential nonlinearity is proposed and discussed. Dynamic analysis of the integer-order jerk system shows the existence of chaotic oscillations. A model for the fractional-order jerk ... -
An Exponential Jerk System: Circuit Realization, Fractional Order and Time Delayed Form with Dynamical Analysis and Its Engineering Application
Rajagopal, Karthikeyan; Akgül, Akif; Jafari, Sajad; Karthikeyan, Anitha; Çavuşoğlu, Ünal; Kaçar, Sezgin (World Scientific Publ Co Pte Ltd, 2019)Simple dynamical systems are of interest always. In this paper, we propose a simple jerk system with one exponential nonlinearity. Dynamical properties of the proposed system are investigated. To show the practical ... -
A family of circulant megastable chaotic oscillators, its application for the detection of a feeble signal and PID controller for time-delay systems by using chaotic SCA algorithm
Rajagopal, Karthikeyan; Çimen, Murat Erhan; Jafari, Sajad; Singh, Jay Prakash; Roy, Binoy Krishna; Akmeşe, Ömer Faruk; Akgül, Akif (Pergamon-Elsevier Science Ltd, 2021)Chaotic systems with cyclic symmetry are very rare and have been less discussed in the literature. Similarly, megastable oscillators, which can have a finite or infinite number of coexisting attractors, have also attracted ... -
Fractional Order Simple Chaotic Oscillator with Saturable Reactors and Its Engineering Applications
Rajagopal, Karthikeyan; Jafari, Sajad; Kaçar, Sezgin; Karthikeyan, Anitha; Akgül, Akif (Kaunas Univ Technology, 2019)Chaos is often observed in forced nonlinear electrical circuits with saturable reactors. Simplest of such a circuit is presented and investigated in both integer order and non-integer (fractional) order form. For numerical ... -
Fractional-Order Analysis of Modified Chua's Circuit System with the Smooth Degree of 3 and Its Microcontroller-Based Implementation with Analog Circuit Design
Wang, Junxia; Xiao, Li; Rajagopal, Karthikeyan; Akgül, Akif; Çiçek, Serdar; Arıcıoğlu, Burak (Mdpi, 2021)In the paper, we futher consider a fractional-order system from a modified Chua's circuit system with the smooth degree of 3 proposed by Fu et al. Bifurcation analysis, multistability and coexisting attractors in the the ... -
Infinite attractors in a chaotic circuit with exponential memristor and Josephson junction resonator
Ramakrishnan, Balamurali; Durdu, Ali; Rajagopal, Karthikeyan; Akgül, Akif (Elsevier Gmbh, 2020)Memristors play a vital role in the design of high density and low power memory devices. Considering the complex behaviour of memristor devices because of the feature that its memductance changes with the input current, ... -
Multiscroll chaotic system with sigmoid nonlinearity and its fractional order form with synchronization application
Rajagopal, Karthikeyan; Durdu, Ali; Jafari, Sajad; Uyaroğlu, Yılmaz; Karthikeyan, Anitha; Akgül, Akif (Pergamon-Elsevier Science Ltd, 2019)In this paper, a multiscroll snap oscillator with hyperbolic tangent function is proposed. There is no limitation in the number of scrolls and it can be increased by proper choice of a specific function. The Lyapunov ... -
Multistability and Coexisting Attractors in a New Circulant Chaotic System
Rajagopal, Karthikeyan; Akgül, Akif; Viet-Thanh Pham; Alsaadi, Fawaz E.; Nazarimehr, Fahimeh; Alsaadi, Fuad E.; Jafari, Sajad (World Scientific Publ Co Pte Ltd, 2019)In this paper, a new four-dimensional chaotic flow is proposed. The system has a cyclic symmetry in its structure and shows a complicated, chaotic attractor. The dynamical properties of the system are investigated. The ... -
A novel dissipative and conservative megastable oscillator with engineering applications
Rajagopal, Karthikeyan; Singh, Jay Prakash; Akgül, Akif; Karthikeyan, Anitha; Duraisamy, Prakash; Roy, Binoy Krishna; Karaca, Ahmet (World Scientific Publ Co Pte Ltd, 2020)In this paper, we have proposed a new chaotic megastable oscillator which has both conservative and dissipative characters depending on the selection of parameters. Various dynamical characteristics including megastability ... -
Persistence and coexistence of infinite attractors in a fractal Josephson junction resonator with unharmonic current phase relation considering feedback flux effect
Karthikeyan, Anitha; Çimen, Murat Erhan; Akgül, Akif; Boz, Ali Fuat; Rajagopal, Karthikeyan (Springer, 2021)Josephson junction resonators are the devices which exhibit complex behaviours as a consequence of their inductive properties. Even though the insulating medium between Josephson junctions (JJs) is normally considered ... -
A Simple Chaotic System With Topologically Different Attractors
Rajagopal, Karthikeyan; Akgül, Akif; Moroz, Irene M.; Wei, Zhouchao; Jafari, Sajad; Hussain, Iqtadar (IEEE-Inst Electrical Electronics Engineers Inc, 2019)There have been many different investigations of nonlinear dynamical systems. In this paper, we introduce a new chaotic system. In the proposed system, the attractor can be modified by adding a nonlinear term to the third ... -
A simple fractional-order chaotic system based on memristor and memcapacitor and its synchronization application
Akgül, Akif; Rajagopal, Karthikeyan; Durdu, Ali; Pala, Muhammed Ali; Boyraz, Ömer Faruk; Yıldız, Mustafa Zahid (Pergamon-Elsevier Science Ltd, 2021)Memelements play an important part in the design of high density memory systems and low power memory. In this paper, we created a novel fractional-order chaotic circuit with a memristor and a memcapacitor with a linear ... -
Simulation and experimental implementations of memcapacitor based multi-stable chaotic oscillator and its dynamical analysis
Akgül, Akif; Kengne, Jacques; Rajagopal, Karthikeyan; Viet-Thanh Pham; Varan, Metin; Karthikeyan, Anitha; Kutlu, Mustafa Çağrı (Iop Publishing Ltd, 2021)In this work, linear quadratic regulator (LQR) method is proposed for controlling and synchronizing memcapacitor based chaotic system (MMCO). The MMCO is constructed with a charge controller memcapacitor, a resistor, a ... -
Spiral Waves in a Lattice Array of Josephson Junction Chaotic Oscillators with Flux Effects
Ramakrishnan, Balamurali; Ramamoorthy, R.; Li, Chunbiao; Akgül, Akif; Rajagopal, Karthikeyan (Hindawi Limited, 2021)Josephson junction devices play a significant role in various physical nonlinear systems because of their complex characteristics. Chaotic phenomenon in various types of Josephson junction devices has been widely reported, ...