In this paper, a new path integration algorithm is proposed specifically for the stochastic vibro-impact system. By introducing the concept of absorption surface and the impact completion condition, this new path integration algorithm can be directly used to study the stochastic response of vibro-impact systems without any non-smooth approximation. The algorithm is suitable for arbitrary recovery coefficients

The multi-soliton solutions and breathers to the coupled higher-order nonlinear Schrödinger (CH-NLS) equation are derived in this work via the Riemann–Hilbert approach. Firstly, the spectral structure of the CH-NLS equation is investigated and then a matrix Riemann–Hilbert problem on the real axis is strictly formulated. Secondly, by solving the special Riemann–Hilbert problem with no reflection where

We study the performance of vibrational energy harvesting systems with piezoelectric and magnetic inductive transducers, assuming the power of external disturbance concentrated around a specific frequency. Both linear and nonlinear harvester models are considered. We use circuit theory and equivalent circuits to show that a large improvement in both the harvested energy and the power efficiency is

This paper studies the faster attitude stabilization problem of receiver aircraft during the refueling phase. Dynamic models of receiver aircraft subject to practical uncertainties and disturbances are established, where the uncertain inertia, the wind disturbance, the time-varying inertia, and the shift of the center of mass are explicitly considered. A faster finite-time stable system is preliminarily

One of the widely-used ways in chaos-based cryptography to generate pseudo-random sequences is to use the least significant bits or digits of finite-precision numbers defined by the chaotic orbits. In this study, we show that the results obtained using such an approach are very prone to rounding errors and discretization effects. Thus, it appears that the generated sequences are close to random even

In this paper, a review of the nonlinear aspects of the mechanical inerter will be presented. The historical context goes back to the development of isolators and absorbers in the first half of the twentieth century. Both mechanical and fluid-based nonlinear inerter devices were developed in the mid- and late twentieth century. However, interest in the inerter really accelerated in the early 2000s

In this study, a generalized equal-peak principle is established to suppress the multimodal vibration of a multiple-degree-of-freedom (M-DOF) nonlinear system. Based on the proposed generalized principle, the design procedure of the multiple time-delayed vibration absorbers (TDVAs) is carried out. By four conditions in the proposed generalized principle, the objective of suppressing all the resonance

In this paper, a variable-coefficient nonlinear Schrödinger equation that describes the optical soliton propagation in dispersion management fiber systems is studied. Two- and three-soliton solutions are obtained by using the Hirota bilinear method. Based on those solutions, the effects of related parameters on optical soliton propagation are discussed. By choosing different values of the third-order

Since the outbreak in Brazil, Zika has received the worldwide attention. Zika virus is mainly transmitted via the bites of Aedes mosquito. Recently, experimental evidence demonstrates that Zika virus in contaminated aquatic environments can be transmitted to aquatic mosquitoes through breeding. To study the effects of contaminated aquatic environments on Zika transmission, we propose a new Zika model

The bifurcation characteristics of the active magnetic bearing-rotor system subjected to the external excitation were investigated analytically when it was operating at a speed far away from its natural frequencies. During operation of the system, some nonlinear factors may be prominent, for example, the nonlinearity of bearing force and current saturation. Nonlinear factors can lead to some complicated

This note points out that the proof for a widely and mostly used (uniform) asymptotic stability theorem for Caputo fractional-order systems, presented by the article “Stability analysis of Caputo fractional-order nonlinear systems revisited” published in Nonlinear Dynamics, is incorrect.

How populations distribute in both space and time is one of the key issues in ecological systems, which can characterize the relationship between populations, space–time structure and evolution law. Consequently, pattern dynamics in ecosystems has been widely investigated including their causes and ecological functions. In order to systematically understand the interactions in ecosystems, we summarize

The Editor-in-Chief is issuing an Editorial Expression of Concern for this Article.

The article “MDOF extension.

By March 2020, China and Singapore had achieved remarkable results in the prevention and control of COVID-19, but in April Singapore’s outbreak began to deteriorate, while China’s remained controlled. Using detailed data from Tianjin, China, and Singapore, a stochastic discrete COVID-19 epidemic model was constructed to depict the impact of the epidemic. Parameter estimation and sensitivity analysis

Motivated by today’s huge volume of data that needs to be handled in secrecy, there is a wish to develop not only fast and light but also reliably secure cryptosystems. Chaos allows for the creation of pseudo-random numbers (PRNs) by low-dimensional transformations that need to be applied only a small number of times. These two properties may translate into a chaos-based cryptosystem that is both fast

The Wada index based on the weighted and truncated Shannon entropy is presented in this paper. The proposed Wada index can detect if a given basin boundary is a Wada boundary. Moreover, the Wada index does represent the number and the distribution of different colors (attractors) in the two-dimensional phase space of initial conditions. The Wada index is based on the standard box counting algorithm

This paper seeks to address the problem of finite-time stabilization for a class of uncertain Hamiltonian systems via sliding mode control approach. A novel sliding function in connection with the state and energy function of the considered system is constructed, and then, a suitable controller is designed to drive the state trajectories onto the specified sliding surface before the given finite-time

Drive-side teeth engaging, tooth disengagement and back-side teeth contacting are three meshing states of the spur gear pair. The influence of different meshing states on system safety is different. The safety performances of the system are classified into three safety levels, i.e., safe, quasi-safe and unsafe according to the influence of the meshing state. Three safety domains corresponding to three

The conventional linear control methods are difficult to meet the control requirements of high-performance speed regulation of asynchronous motor due to the nonlinear and multi-variable problems of induction motor. A passive-based control method of induction motor with the full-order state observer is proposed with the Euler–Lagrange equation of motion of the induction motor. Based on the relationship

In this work, we develop a general model of a mass sensor made of N weakly mechanically coupled microbeams subject to electric actuation. The developed model is verified by comparing the simulated pull-in voltages, natural frequencies, and frequency response of a two-weakly coupled beam system against their experimental counterparts reported in the literature. The sensitivity of the mass sensor in

Variable coefficients nonlinear evolution equations offer us with more real aspects in the inhomogeneities of media and nonuniformities of boundaries than their counter constant coefficients in some real-world problems. Under consideration is a nonlinear variable coefficients Schrödinger’s equation with spatio-temporal dispersion in the Kerr law media. We are aimed at constructing novel solutions to

The ability to robustly and efficiently control the dynamics of nonlinear systems lies at the heart of many current technological challenges, ranging from drug delivery systems to ensuring flight safety. Most such scenarios are too complex to tackle directly, and reduced-order modelling is used in order to create viable representations of the target systems. The simplified setting allows for the development

We present an example of demonstration for the basin boundaries in classical rearrangement scattering with particular emphasis on the breakup channel. Whereas the basin boundaries of the other arrangement channels are given by stable manifolds of periodic orbits in the interaction region, the basin boundary of the breakup channel is given by the stable manifold of a particular subset in the set of

Pseudo-random number generator (PRNG) has been widely used in digital image encryption and secure communication. This paper reports a novel PRNG based on a generalized Sprott-A system that is conservative. To validate whether the system can produce high quality chaotic signals, we numerically investigate its conservative chaotic dynamics and the complexity based on the approximate entropy algorithm

When an isolated equilibrium of a nonlinear system is locally attractive, it might be difficult to estimate and then enlarge its Region of Attraction (RA). To solve this problem, this paper, by means of impulsive control, provides an effective method, i.e., state-dependent edge impulse (STDEI) combining with SOS programming and trajectory reversing with convex hull. Based on SOS programming and trajectory

This paper investigates mixed-mode oscillations (MMOs) with a three-dimensional conductance-based cardiac action potential model, which makes the heart beat in a nonrenewable way. The 3D model was entailed by utilizing voltage-dependent timescales to describe the mechanism in which MMOs are generated. As expected, motivated by geometric singular perturbation theory, our analysis explains in detail

A noticeable research topic in optics is optical phenomena associated with the nonstatic waves. If the parameters of a medium vary by a periodic or randomly exerted perturbation, the waves become nonstatic, leading to a variation in their shapes. The decay of wave amplitudes through dissipation is also an outcome of wave nonstaticity. In this research, we demonstrate that Schrödinger equation allows

In this paper, outcomes of the study on the Bäcklund transformation, Lax pair, and interactions of nonlinear waves for a generalized (2 + 1)-dimensional nonlinear wave equation in nonlinear optics, fluid mechanics, and plasma physics are presented. Via the Hirota bilinear method, a bilinear Bäcklund transformation is obtained, based on which a Lax pair is constructed. Via the symbolic computation,

MicroRNAs are able to modulate gene expression at the posttranscriptional level and play an essential role in various biological processes. In this paper, we establish a general model of an miRNA-mediated gene regulatory network motif with extracellular stimulus. Dynamical properties of the regulatory motif without stimulus focus on diverse codimension-1 and codimension-2 bifurcation analyses of two

The occurrence of synchronization and amplitude death phenomena due to the coupled interaction of limit cycle oscillators (LCO) has received increased attention over the last few decades in various fields of science and engineering. Studies pertaining to these coupled oscillators are often performed by studying the effect of various coupling parameters on their mutual interaction. However, the effect

Atomic force microscope (AFM) is one of the most versatile and powerful devices capable of producing high-resolution images of nanomaterial. Many researchers are widely investigating to improve the scanning speed and image quality of AFM by proposing different techniques. Here, we aim to present a novel approach based on the smooth orthogonal decomposition for the estimation of the surface topography

Nowadays, vehicles are being fitted with systems that improve their maneuverability, stability, and comfort in order to reduce the number of accidents. Improving these aspects is of particular interest thanks to the incorporation of autonomous vehicles onto the roads. The knowledge of vehicle sideslip and roll angles, which are among the main causes of road accidents, is necessary for a proper design

In this paper, the robust finite-time tracking problem is addressed for a square fully actuated class of nonlinear systems subjected to disturbances and uncertainties. Firstly, two applicable lemmas are derived and novel nonlinear sliding surfaces (manifolds) are defined by applying these lemmas. Secondly, by developing the nonsingular terminal sliding mode control, two different types of robust nonlinear

In this paper, a neural network-based event-triggered fault detection scheme is addressed within the finite-frequency domain for a class of nonlinear Markov jump system. Initially, an approximation model based on multilayer neural network to alternate the nonlinear Markov jump system is constructed. For the purpose of saving the communication network bandwidth, a transmission mechanism based on the

This is the first paper of a trilogy intended by the authors in what concerns a unified approach to the stability of thermoelastic arched beams of Bresse type under Fourier’s law. Our main goal in this starting work is to develop an original observability inequality for conservative Bresse systems with non-constant coefficients. Then, as a powerful application, we prove mathematically that the stability

The Hopf bifurcation behavior is an important issue for the nonlinear dynamic analysis of gas foil bearing (GFB)-rotor systems. However, there is a lack of detailed study on different types of Hopf bifurcation and their corresponding characteristics for GFB-rotor systems. This paper is intended to provide a clear and systematic insight into the nonlinear dynamic characteristics of GFB-rotor systems

Juggling a devil-stick can be described as a problem of non-prehensile manipulation. Assuming that the devil-stick remains confined to the vertical plane, the problem of juggling the stick between two symmetric configurations is considered. Impulsive forces are applied to the stick intermittently and the impulse of the force and its point of application are modeled as control inputs to the system.

The dynamic force transmissibility (DFT) of aerospace flywheel rotor system (FRS) supported by angular contact ball bearings (ACBBs) is examined in this paper. The influence of combined loads and contact angle variation is considered in the Sjovall formula to accurately solve the load distribution and nonlinear stiffness of ACBB. Subsequently, the lateral vibration model of FRS is established by considering

This paper focuses on the output feedback tracking control for fractional-order interconnected systems with unmodeled dynamics. The reduced order high gain K-filters are designed to construct the estimation of the unavailable system state. Unmodeled dynamics is extended to the general fractional-order dynamical systems for the first time which is characterized by introducing a dynamical signal r(t)

This work investigates the dynamics of a microbeam-based MEMS device in the neighborhood of a 2:1 internal resonance between the third and fifth vibration modes. The saturation of the third mode and the concurrent activation of the fifth are observed. The main features are analyzed extensively, both experimentally and theoretically. We experimentally observe that the complexity induced by the 2:1 internal

We have presented in the current analytic research the generating formulae and results of direct mathematical modelling of non-classical trends for COVID-19’s evolution in world which, nevertheless, can be divided into two types: (1) the general trends for European countries such as Germany presented by the curve of modified sigmoid-type with up-inclination of the upper limit of saturation (at the

The lift force acting on a purely translational galloping oscillator can be well approximated by using the quasi-steady theory, which states that the flow around a galloping body in motion is very similar to the known flow around a fixed body provided a minimum free stream velocity threshold and a similarity principle are satisfied. However, for oscillators undergoing coupled translational–rotational

We investigate the inhomogeneous higher-order nonlinear Schrödinger (INHLS) equation including cubic–quintic–septic (CQS) nonlinear terms and gain or loss with variable coefficients. The exact analytic solution that describes dark soliton-type pulse propagation is found for the model by employing the ansatz method. Unlike the traditional \(\text {tanh}\) dark soliton in Kerr-type media, the functional

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 homogeneous, the fact that lithography is used to form the layer, it has fractal substrates. Such JJs are identified as fractal Josephson junctions (FJJs). In this paper, a new chaotic

Distributed-order calculus can be understood as a further generalisation of integer- and fractional-order calculus. Such a general case allows the modelling and understanding of a more extensive engineering and physical systems class. This paper proposes a controller design that enforces the predefined-time convergence of the solution of a distributed-order dynamical system. Besides, a predefined-time

We report experimental evidence of the destabilization of a 3D torus obtained when a small subharmonic perturbation is added to a 2D torus characteristic of a driven relaxation oscillator. The Poincaré sections indicate that the torus breakup is sensitive to the phase difference between the main driving frequency and its first subharmonic perturbing component. The observed transition confirms the Newhouse

In this paper, a new four-dimensional dissipative chaotic system which can produce multiple asymmetric attractors is designed and its dynamical behaviors are analyzed. The basin of attraction reveals the asymmetric multistability of the system. In addition, it is very interesting to observe different types of asymmetric coexisting attractors as the bifurcation parameters change. The spectral entropy

The neural firing activities related to information coding maintaining the information transmission vary qualitatively considering the electromagnetic induction. The firing of a single neuron can be investigated by Hopf bifurcation analysis. In this paper, with the help of the center manifold theory and algebraic invariants method, general parameter conditions are obtained for the existence and stability

NiTiNOL-steel wire rope (NiTi-ST) is a new vibration absorber with nonlinear stiffness and hysteretic damping. Although there are many studies on NiTi-ST nonlinear identification, there are few studies on vibration suppression for laminated structures with NiTi-ST. In the present work, the NiTi-ST is integrated with a composite laminated beam for structural vibration suppression for the first time

This manuscript explores the effect of viscoelasticity on static bifurcations: such as pitchfork, saddle-node, and transcritical bifurcations, of a single-degree-of-freedom mechanical oscillator. The viscoelastic behavior is modeled via a differential form, where the extra degree of freedom represents the internal force provided by the viscoelastic element. The governing equations are derived from

In this work, we demonstrate numerically that two-frequency excitation is an effective method to produce chaotification over very large regions of the parameter space for the Duffing oscillator with single- and double-well potentials. It is also shown that chaos is robust in the last case. Robust chaos is characterized by the existence of a single chaotic attractor which is not altered by changes in

Agitator tanks are widely used in industrial fields. Improvement in their efficiency is critical to achieving high productivity. That is to say, an agitator tank system should have a short response time to produce a desired reagent with an accurate solution concentration and a moderate liquid level. Therefore, a noise-rejection zeroing dynamics (NRZD) model for the control of the agitator tank based

In order to solve the constrained-input problem and reduce the computing resources, a novel event-triggered optimal control method is proposed for a class of discrete-time nonlinear systems. In the proposed method, the event-triggered control policy is applied to the globalized dual heuristic dynamic programming (GDHP) algorithm. Compared with the traditional adaptive dynamic programming (ADP) control

In this paper, the finite-time non-fragile boundary feedback control problem is investigated for a class of nonlinear parabolic systems, where both the multiplicative and additive controller gain variations are considered to describe the actuator parameter perturbation. Non-fragile boundary control strategies are designed with respect to two controller gain variations via collocated or non-collocated

This paper proposes two novel adaptive control designs for the feedback signals used in the control-based continuation paradigm to track families of periodic orbits of periodically excited dynamical systems, including black box simulation models and physical experiments. The proposed control designs rely on modifications to the classical model reference adaptive control framework and the more recent

In this paper, by introducing the definition of the solution, we prove the existence and uniqueness of the solution for nonlinear on–off switched systems with switching at variable times (NVTSS). Based on this result, the continuous dependence and differentiability of the solution of NVTSS (4) with respect to the initial state are presented. Besides, the switching phenomenon (the integral curve of

To simulate the price fluctuation dynamics of financial markets, a novel financial price model is developed by the voter dynamic system on the Watts-Strogtz small-world network and the random jump process. The voter system is a classical statistical physics system, which describes the dynamics of voters’ attitudes towards a certain topic in the mutual influence. The Watts-Strogtz small-world network

The paper presents a generalized composite noncertainty-equivalence adaptive control system for the control of a prototypical aeroelastic wing section using a single trailing-edge control surface. The plunge–pitch (two-degree-of-freedom) dynamics of this aeroelastic system include torsional pitch-axis nonlinearity. The open-loop system exhibits limit cycle oscillations beyond a critical free-stream

This paper investigates the effect of model uncertainty on the nonlinear dynamics of a generic aeroelastic system. Among the most dangerous phenomena to which these systems are prone, Limit Cycle Oscillations are periodic isolated responses triggered by the nonlinear interactions among elastic deformations, inertial forces, and aerodynamic actions. In a dynamical systems setting, these responses typically