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## Chaos and hyperchaos after secondary Neimark-Sacker bifurcation in a model of radio-physical generator

Nonlinear Dynamics. 2019. Vol. 97. P. 2355-2370.

Using an example of a radiophysical generator model, scenarios for the formation of various chaotic attractors are described, including chaos and hyperchaos. It is shown that as a result of a secondary Neimark–Sacker bifurcation, a hyperchaos with two positive Lyapunov exponents can occur in the system. A comparative analysis of chaotic attractors born as a result of loss of smoothness of an invariant curve, as a result of period-doubling bifurcations, and as a result of secondary Neimark–Sacker bifurcation was carried out.

Stankevich N., Kuznetsov A., Seleznev E., Chaos, Solitons and Fractals 2021 Vol. 147 Article 110998

Appearance of chaotic dynamics as a result of multi-frequency tori destruction is carried out on the example of a model of a multimode generator. Quasiperiodic bifurcations occurring with multi-frequency tori are discussed in the context of the Landau-Hopf scenario. Structure of the parameter space is studied, areas with various chaotic dynamics, including chaos and hyperchaos, ...

Added: May 12, 2021

Stankevich N., Volkov E., Nonlinear Dynamics 2018 Vol. 94 No. 4 P. 2455-2467

The emergence of multistability in a simplethree-dimensionalautonomousoscillatorisinvestigatedusingnumericalsimulations,calculationsofLyapunov exponents and bifurcation analysis over a broad area of two-dimensional plane of control parameters. Using Neimark–Sacker bifurcation of 1:1 limit cycle asthestartingregime,manyparameterislandswiththe coexisting attractors were detected in the phase diagram,includingthecoexistenceoftorus,resonantlimit cycles and chaos; and transitions between the regimes were considered in detail. The overlapping between resonant limit cycles ...

Added: December 2, 2019

Stankevich N., Kazakov A., Gonchenko S., Chaos 2020 Vol. 30 Article 123129

The generalized four-dimensional Rössler system is studied. Main bifurcation scenarios leading to a hyperchaos are described phenomenologically and their implementation in the model is demonstrated. In particular, we show that the formation of hyperchaotic invariant sets is related mainly to cascades (finite or infinite) of nondegenerate bifurcations of two types: period-doubling bifurcations of saddle cycles with a ...

Added: January 18, 2021

Кузнецов А. П., Stankevich N., Щеголева Н. А., Известия высших учебных заведений. Прикладная нелинейная динамика 2021 Т. 29 № 1 С. 136-159

The purpose of this study is to describe the complete picture of synchronization of two coupled generators of quasi-periodic oscillations, to classify various types of synchronization, to study features of occurrence and destruction of multi-frequency quasi-periodic oscillations. Methods. The object of the research is systems of ordinary differential equations of various dimensions. The work uses the fourth-order Runge–Kutta ...

Added: February 2, 2021

Stankevich N., Shchegoleva N. A., Sataev I. R. et al., Journal of Computational and Nonlinear Dynamics 2020 Vol. 15 No. 11 P. 111001

Using an example a system of two coupled generators of quasiperiodic oscillations, we study the occurrence of chaotic dynamics with one positive, two zero and several negative Lyapunov exponents. It is shown that such dynamic arises as a result of a sequence of bifurcations of two-frequency torus doubling and involve saddle tori occurring at their ...

Added: September 4, 2020

Sataev I. R., Stankevich N., Chaos 2021 Vol. 31 No. 2 Article 023140

We study the hyperchaos formation scenario in the modified Anishchenko–Astakhov generator. The scenario is connected with the existence of sequence of secondary torus bifurcations of resonant cycles preceding the hyperchaos emergence. This bifurcation cascade leads to the birth of the hierarchy of saddle-focus cycles with a two-dimensional unstable manifold as well as of saddle hyperchaotic sets resulting ...

Added: February 26, 2021

Alexeeva T., Barnett W. A., Kuznetsov N. V. et al., Chaos, Solitons and Fractals 2020 Vol. 140 Article 110239

Forecasting and analyses of the dynamics of financial and economic processes such as deviations of macroeconomic aggregates (GDP, unemployment, and inflation) from their long-term trends, asset markets volatility, etc., are challenging because of the complexity of these processes. Important related research questions include, first, how to determine the qualitative properties of the dynamics of these ...

Added: October 21, 2020

Stankevich N., Volkov E., Chaos 2021 Vol. 31 No. 10 Article 103112

We investigate the dynamics of three identical three-dimensional ring synthetic genetic oscillators (repressilators) located in different cells and indirectly globally coupled by quorum sensing whereby it is meant that a mechanism in which special signal molecules are produced that, after the fast diffusion mixing and partial dilution in the environment, activate the expression of a ...

Added: October 12, 2021

Garashchuk I., Kazakov A., Sinelshchikov D. et al., Chaos 2019 Vol. 29 No. 6 P. 063131-1-063131-16

We study nonlinear dynamics of two coupled contrast agents that are micrometer size gas bubbles encapsulated into a viscoelastic shell. Such bubbles are used for enhancing ultrasound visualization of blood flow and have other promising applications like targeted drug delivery and noninvasive therapy. Here, we consider a model of two such bubbles interacting via the ...

Added: December 16, 2019

Stankevich N., Dvorak A., Astakhov V. et al., Regular and Chaotic Dynamics 2018 Vol. 23 No. 1 P. 120-126

The dynamics of two coupled antiphase driven Toda oscillators is studied. We demonstrate three diﬀerent routes of transition to chaotic dynamics associated with diﬀerent bifurcations of periodic and quasi-periodic regimes. As a result of these, two types of chaotic dynamics with one and two positive Lyapunov exponents are observed. We argue that the results obtained ...

Added: December 2, 2019

Kruglov V., Krylosova D., Sataev I. R. et al., Chaos 2021 Vol. 31 No. 7 Article 073118

Transition to chaos via the destruction of a two-dimensional torus is studied numerically using an example of the Hénon map and the Toda oscillator under quasiperiodic forcing and also experimentally using an example of a quasi-periodically excited RL–diode circuit. A feature of chaotic dynamics in these systems is the fact that the chaotic attractor in ...

Added: July 15, 2021

Skripchenko A., Hubert P., Avila A., Diffusion for chaotic sections of 3-periodic surfaces / Cornell University. Series math "arxiv.org". 2014. No. 1412.7913.

We study chaotic plane sections of some particular family of triply periodic surfaces. The question about possible behavior of such sections was posed by S. P. Novikov. We prove some estimations on diffusion rate of these sections using the connection between Novikov's problem and systems of isometries - some natural generalization of interval exchange transformations. ...

Added: January 27, 2015

Avila A., Hubert P., Skripchenko A., Inventiones Mathematicae 2016 Vol. 206 No. 1 P. 109-146

We study chaotic plane sections of some particular family of triply periodic surfaces. The question about possible behavior of such sections was posed by S. P. Novikov. We prove some estimations on the diffusion rate of these sections using the connection between Novikov’s problem and systems of isometries—some natural generalization of interval exchange transformations. Using ...

Added: November 9, 2016

Stankevich N., Mosekilde E., Koseska A., European Physical Journal: Special Topics 2018 Vol. 227 P. 747-756

Complex biochemical networks are commonly characterised by the coexistence of multiple stable attractors. This endows living systems with plasticity in responses under changing external conditions, thereby enhancing their probability for survival. However, the type of such attractors as well as their positioning can hinder the likelihood to randomly visit these areas in phase space, thereby ...

Added: December 2, 2019

Karatetskaia E., Шыхмамедов А. И., Kazakov A., Chaos 2021 Vol. 31 Article 011102

A Shilnikov homoclinic attractor of a three-dimensional diffeomorphism contains a saddle-focus fixed point with a two-dimensional unstable invariant manifold and homoclinic orbits to this saddle-focus. The orientation-reversing property of the diffeomorphism implies a symmetry between two branches of the one-dimensional stable manifold. This symmetry leads to a significant difference between Shilnikov attractors in the orientation-reversing ...

Added: September 8, 2021

Kuryzhov E., Karatetskaia E., Mints D., Russian Journal of Nonlinear Dynamics 2021 Vol. 17 No. 2 P. 165-174

We consider the system of two coupled one-dimensional parabola maps. It is well known that the parabola map is the simplest map that can exhibit chaotic dynamics, chaos in this map appears through an infinite cascade of period-doubling bifurcations. For two coupled parabola maps we focus on studying attractors of two types: those which resemble ...

Added: September 8, 2021

Kazakov A., Козлов А. Д., Журнал Средневолжского математического общества 2018 Т. 20 № 2 С. 187-198

In the paper a new method of constructing of three-dimensional flow systems with different chaotic attractors is presented. Using this method, an example of three-dimensional system possessing an asymmetric Lorenz attractor is obtained. Unlike the classical Lorenz attractor, the observed attractor does not have symmetry. However, the discovered asymmetric attractor, as well as classical one, ...

Added: October 26, 2018

Купцов П. В., Kuptsova A. V., Stankevich N., Russian Journal of Nonlinear Dynamics 2021 Vol. 17 No. 1 P. 5-21

We suggest a universal map capable of recovering the behavior of a wide range of dynamical systems given by ODEs. The map is built as an artificial neural network whose weights encode a modeled system. We assume that ODEs are known and prepare training datasets using the equations directly without computing numerical time series. Parameter ...

Added: April 3, 2021

Fougeron C., Skripchenko A., Monatshefte fur Mathematik 2021 Vol. 194 No. 4 P. 767-787

We introduce a new strategy to prove simplicity of the spectrum of Lyapunov exponents that can be applied to a wide class of Markovian multidimensional continued fraction algorithms. As an application we use it for Selmer algorithm in dimension 2 and for the Triangle sequence algorithm and show that these algorithms are not optimal.
There is ...

Added: February 10, 2021

СПб.: Главная (Пулковская) астрономическая обсерватория РАН, 2018

Сборник содержит доклады, представленные на XXII Всероссийскую ежегодную конференцию по физике Солнца «Солнечная и солнечно-земная физика – 2018» (8 – 12 октября 2018 года, ГАО РАН, Санкт-Петербург). Конференция проводилась Главной (Пулковской) астрономической обсерваторией РАН при поддержке Российского фонда фундаментальных исследований, секции «Солнце» Научного совета по астрономии РАН и секции «Плазменные процессы в магнитосферах планет, атмосферах ...

Added: November 21, 2018

Garashchuk I., Sinelshchikov D., Kudryashov N. A., Regular and Chaotic Dynamics 2018 Vol. 23 P. 257-272

Contrast agent microbubbles, which are encapsulated gas bubbles, are widely used to enhance ultrasound imaging. There are also several new promising applications of the contrast agents such as targeted drug delivery and noninvasive therapy. Here we study three models of the microbubble dynamics: a nonencapsulated bubble oscillating close to an elastic wall, a simple coated ...

Added: December 16, 2019

Kuznetsov A., Kuznetsov S., Shchegoleva N. et al., Physica D: Nonlinear Phenomena 2019 Vol. 398 P. 1-12

A problem of synchronization of quasiperiodic oscillations is discussed in application to an example of coupled systems with autonomous quasiperiodic dynamics. Charts of Lyapunov exponents are presented that reveal characteristic domains on the parameter plane such as oscillator death, complete synchronization, phase synchronization of quasiperiodic oscillations, broadband synchronization, broadband quasiperiodicity. Features of each kind of ...

Added: December 2, 2019

Кузнецов А. П., Седова Ю. В., Stankevich N., Журнал технической физики 2021 Т. 91 № 11 С. 1619-1624

Исследована возбуждаемая гармоническим сигналом система двух диссипативно связанных генераторов,
способных демонстрировать автономные квазипериодические колебания. Представлены ляпуновские карты,
выявляющие режимы инвариантных торов разной размерности и хаоса. Представлены фазовые портреты в
стробоскопическом сечении и двойном сечении Пуанкаре. Обсуждено сосуществование различных режимов,
в частности, бифуркации инвариантных торов. ...

Added: October 6, 2021

Kuznetsov N. V., Mokaev T. N., Alexeeva T., Ekaterinburg: Институт математики и механики УрО РАН им. Н.Н. Красовского, 2019

Added: October 30, 2019