Chaos Solitons & Fractals最新文献

{"title":"Linear–quadratic optimal control of infinite-dimensional stochastic evolution equation with jumps","authors":"Shijun Wang ,&nbsp;Maoning Tang ,&nbsp;Qingxin Meng","doi":"10.1016/j.chaos.2025.116494","DOIUrl":"10.1016/j.chaos.2025.116494","url":null,"abstract":"<div><div>This paper discusses a stochastic linear–quadratic optimal control problem with jumps in an infinite-dimensional Hilbert space. The state equation of this linear–quadratic optimal control problem is a stochastic evolution equation driven by a Poisson random martingale measure and a one dimensional Brownian motion. The cost functional is a quadratic generalized function consisting of a state process and a control process. In order to ensure the suitability and solvability of the problem, firstly, by using the infinite-dimensional stochastic analysis theory, two types of semilinear forward and backward stochastic evolution equations are investigated separately to prove the continuous dependence on the generating elements as well as the existence and uniqueness of the solutions. Secondly, through Yosida approximation theory, a new infinite-dimensional duality relation is constructed between the state equations and the adjoint equations, which is used to obtain the dual representation of the optimal control and the solvability of the infinite-dimensional stochastic Hamiltonian system. Here the stochastic Hamiltonian system consisting of state equations, adjoint equations and stationarity conditions is a infinite-dimension fully coupled forward backward stochastic evolution equations. Finally, an infinite-dimensional Riccati equation for the control system is introduced to decouple the stochastic Hamiltonian system, and the state feedback representation of the optimal control and the corresponding value function are derived.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116494"},"PeriodicalIF":5.3,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-autonomous standard nontwist map","authors":"Marcos V. de Moraes ,&nbsp;Iberê L. Caldas ,&nbsp;Yves Elskens","doi":"10.1016/j.chaos.2025.116492","DOIUrl":"10.1016/j.chaos.2025.116492","url":null,"abstract":"<div><div>Area-preserving nontwist maps locally violate the twist condition, giving rise to shearless curves. Nontwist systems appear in different physical contexts, such as plasma physics, climate physics, classical mechanics, etc. Generic properties of nontwist maps are captured by the standard nontwist map, which depends on a convection parameter <span><math><mi>a</mi></math></span> and a modulation coefficient <span><math><mi>b</mi></math></span>. In the spirit of non-autonomous systems, we consider the standard nontwist map (SNM) with a linearly increasing modulation coefficient, and we investigate the evolution of an ensemble of points on the phase space that initially lie on the shearless invariant curve in the initial state, called shearless snapshot torus. Differently from the SNM with constant parameters — where we can see different scenarios of collision/annihilation of periodic orbits leading to global transport, depending on the region in the parameter space — for the SNM with time-dependent parameters, the route to chaos is not only related to the path in the <span><math><mrow><mo>(</mo><mi>a</mi><mo>,</mo><mi>b</mi><mo>)</mo></mrow></math></span> parameter space, but also to the scenario of the evolution of parameter <span><math><msub><mrow><mi>b</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span>. In this work, we identify power-law relationships between key parameters for the chaotic transition and the iteration time. Additionally, we analyze system reversibility during the chaotic transition and demonstrate an extra transport, where parameter variation modifies the diffusion coefficient.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116492"},"PeriodicalIF":5.3,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear steady-state traveling solutions of the Kuramoto-Sivashinsky equation coupled with the linear dissipative equation","authors":"Andrey A. Bocharov ,&nbsp;Oleg Yu. Tsvelodub","doi":"10.1016/j.chaos.2025.116572","DOIUrl":"10.1016/j.chaos.2025.116572","url":null,"abstract":"<div><div>A generalization of the known active-dissipative Kuramoto-Sivashinsky equation coupled with a linear dissipative equation is considered. In such a model the region of zero solution instability is shown to depend in a complex way on the specific values of the problem parameters. The families of periodic nonlinear steady-state traveling solutions bifurcating from the zero solution in the vicinity of neutral wave numbers are constructed numerically. The investigation of the stability of these solutions enables obtaining new families that appear as a result of subsequent bifurcations. Among these families the ones that extend into the region of small wave numbers and turn into soliton solutions in the limit by the wave numbers are found among them. Various two-hump solitons are constructed. The research results on the stability of a soliton solution are presented.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116572"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic behaviors of a reaction–diffusion competition system with road diffusion and nonlocal interaction","authors":"You Zhou ,&nbsp;Yao Xu ,&nbsp;Canrong Tian ,&nbsp;Zhi Ling","doi":"10.1016/j.chaos.2025.116458","DOIUrl":"10.1016/j.chaos.2025.116458","url":null,"abstract":"<div><div>We present a two-species competition system that incorporates road diffusion and non-local interactions, which describes a process of biological invasion. Using the modified comparison principle, we derive that the system possesses a unique global solution. We analyze the long-term behavior of the competing populations, that is, whether the invasion succeeds or fails. Our analysis reveals that in cases of weak–strong interaction between species, the weaker one tends to extinction, whereas the stronger one persists. In contrast, when the competition is characterized as weak-weak, both species are able to coexist simultaneously. Additionally, it is demonstrated that the invasion velocity exceeds the speed of traveling wave solutions when the road diffusion coefficient is sufficiently large.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116458"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Light-powered self-swing of a bistable magnetic pendulum utilizing liquid crystal elastomer fibers","authors":"Jun Zhao ,&nbsp;Xincheng Wang ,&nbsp;Yunlong Qiu ,&nbsp;Hongbin Chen ,&nbsp;Kai Li","doi":"10.1016/j.chaos.2025.116565","DOIUrl":"10.1016/j.chaos.2025.116565","url":null,"abstract":"<div><div>Light-powered self-oscillation allows for the direct absorption of heat from ambient illumination to maintain its movement, making it a valuable technology for sensors, energy harvesters and soft robots. However, achieving self-oscillation in pendulum systems remains experimentally challenging. To overcome this limitation, we experimentally proposes a bistable magnetic pendulum that utilizes magnetic forces to provide a lateral pulling force, where the interplay of gravity and magnetic forces allows the pendulum to transition between the light zone and the dark zone, offering a novel mechanism for self-oscillation. Base on the light-responsive characteristic curve of LCE fiber calibrated experimentally, a theoretical model for the bistable magnetic pendulum is established to investigate the dynamic behaviors of the self-swing. Numerical calculation shows that the bistable magnetic pendulum has three modes motion: static, single-periodic self-swing, and complex-periodic self-swing, which aligns with the experimental observations. The self-swing is originated from alternating gravity-to-magnetic transition in dark and magnetic-to-gravity transition in light. Furthermore, the motion state, amplitude, and period of the LCE magnetic pendulum can be controlled by adjusting the light power, magnetization coefficient and thermal time ratio. The proposed bistable magnetic pendulum, with advantages such as not requiring rapid material response, a wide range of adjustable periods, and a simple structure, can provide potential applications in environmental monitoring, robotics, and energy harvesting.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116565"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of next-nearest neighbor interactions on the dynamics of discrete energy transport within neuronal microtubules","authors":"R. Abouem A Ribama ,&nbsp;M. Youssoufa ,&nbsp;R.Y. Ondoua ,&nbsp;Z.I. Djoufack ,&nbsp;J.P. Nguenang","doi":"10.1016/j.chaos.2025.116538","DOIUrl":"10.1016/j.chaos.2025.116538","url":null,"abstract":"<div><div>In this study, we investigate the influence of next-nearest neighbor interactions or homodimer coupling on the dynamics of quantum breathers in neuronal microtubules (nMTs) using both analytical and numerical methods. From the classical model describing the dynamics of the microtubule using a Hamiltonian, we formulated its quantum equivalent through Bose operators. By employing Ehrenfest’s theorem and Glauber’s method of coherent states, we showed that nMT dynamics can be described by the discrete nonlinear Schrödinger equation (DNLSE). The analysis of modulational instability (MI) allowed us to define localization zones for breathers, revealing the impact of the second coupling term and well width on system’s behavior. We conducted numerical simulations to examine three scenarios based on homodimer and heterodimer coupling values in relation to breather propagation. We found that homodimer coupling enhances the temporal distribution of energy and extends breather localization towards the central site. Additionally, we observed that energy within nMTs is quantized with a linear profile, influenced by homodimer coupling. The interaction between two breathers indicated that this coupling also affects energy exchanges, impacting the collective dynamics of microtubules and potentially stabilizing or destabilizing configurations, thereby influencing neuronal responses. These findings enhance the understanding of energy transfer in biological systems such as the nervous system, which is responsible for coordinating actions and rapid communication within the body. This system, also known as the neuronal system, utilizes synapses to transmit signals. In this process, neurons release chemical neurotransmitters that can influence the activity of receiving cells.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116538"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced heat transfer in micropolar fluids with inclined magnetic field and chemical reaction used in solar and geothermal energy systems: A comparative solution with semi-analytical approaches","authors":"P.K. Pattnaik ,&nbsp;Subhajit Panda ,&nbsp;S.R. Mishra ,&nbsp;Rupa Baithalu","doi":"10.1016/j.chaos.2025.116566","DOIUrl":"10.1016/j.chaos.2025.116566","url":null,"abstract":"<div><div>Micropolar fluids have emerged as promising in modern energy systems due to their microstructure and enhanced thermal properties. This present study explores the behavior of free convective polar fluid subjected to an inclined magnetic field. Further, the impact of thermal radiation, internal heat generation, and chemical reaction effect enriches the flow phenomena. The study is vital for numerous real-world applications particularly, in solar thermal collectors, geothermal heat exchangers, electronic cooling systems and energy harvesting devices where the utmost control over heat is critical. The transport model with the governing equations is formulated and suitable dimensionless forms are utilized for the conversion of the non-dimensional form of the model which lead to the involvement of certain characterizing factors. Moreover, to ensure the accuracy, the system is handled through dual approach-employing the semi-analytical Adomian decomposition method (ADM) along-side the numerical approach of fourth-order Runge-Kutta combined with shooting technique. The comprehensive parametric analysis illustrates the impact of several factors involved in the flow phenomena. The results are depicted for the variation of different factors within their range and depicted graphically. Moreover, the important findings are; Assisting flow enhances the velocity distribution near to the lower wall of the channel and the impact is reversed for the opposing case at the upper wall. Thermal and solutal distributions are favourably enhances for the increasing Peclet number but the Nusselt number and Sherwood number retards significantly.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116566"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theoretical analysis and practical application of multi-patch infectious disease model","authors":"Yingzi He,&nbsp;Linhe Zhu","doi":"10.1016/j.chaos.2025.116519","DOIUrl":"10.1016/j.chaos.2025.116519","url":null,"abstract":"<div><div>Human movement plays a key role in the spread of infectious diseases. However, in real life, mobility behavior often exhibits significant heterogeneity. Therefore, secondary contact is considered, which increases the probability that susceptible populations turn exposed. Based on these considerations, a multi-patch system that incorporates the above factors is proposed. First, the dynamics of this system are analyzed. The system’s well-posedness and the impact of the global basic reproduction number on disease transmission are then established. Additionally, the uniqueness and stability of the endemic equilibrium point is proved when the global basic reproduction number exceeds 1. The relationship between the patch-specific basic reproduction number and the global reproduction number is also established. Next, a local analysis examines the internal dynamics of each patch, and the bifurcation phenomena in the system are demonstrated. Finally, in the numerical simulation section, the impact of the basic reproduction number on disease transmission is analyzed through the control variable method and the partial rank correlation coefficient <span><math><mrow><mo>(</mo><mi>P</mi><mi>R</mi><mi>C</mi><mi>C</mi><mo>)</mo></mrow></math></span> method. The model is fitted to actual Human Immunodeficiency Virus <span><math><mrow><mo>(</mo><mi>H</mi><mi>I</mi><mi>V</mi><mo>)</mo></mrow></math></span> data from Africa, with five countries selected as examples based on the clustering principle. The global basic reproduction number is calculated, and the results indicate that the disease does not outbreak when the global basic reproduction number falls below 1. Furthermore, the seasonal autoregressive integrated moving average <span><math><mrow><mo>(</mo><mi>S</mi><mi>A</mi><mi>R</mi><mi>I</mi><mi>M</mi><mi>A</mi><mo>)</mo></mrow></math></span> method is used for prediction to verify our hypothesis, which provides practical significance to the model.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116519"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How to maintain long-term euglycemia in a noisy environment: Insight from a stochastic glucose–insulin metabolism model with correlated Gaussian colored noise","authors":"Yu Zhao ,&nbsp;Damaola Buwajier ,&nbsp;Jie Ren","doi":"10.1016/j.chaos.2025.116536","DOIUrl":"10.1016/j.chaos.2025.116536","url":null,"abstract":"<div><div>Understanding the response of glucose homeostasis regulation mechanism to stochastic environmental fluctuation in vivo and in vitro may benefit to gain quantitative insight into the physiological processes of progression of hyperglycemia. In this paper, we propose a stochastic glucose insulin regulation model, which takes into account the correlated Gaussian color noises to describe the environmental internal and external variability. First, the noise-induced state transition from physiological steady state <span><math><msup><mrow><mi>N</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> to pathological steady state <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> is observed. Then, by analyzing stochastic stability and the stationary probability density (SDP) of the limiting Itô stochastic system, we theoretically explore the factors that influence the individuals to deviate from the physiological steady state. Additionally, the mean first passage time (MFPT) of the attraction domain of potential well corresponding to the physiological steady state is also calculated to validate the observations. These results demonstrate that the correlation direction of two noises presents different influence pathways of the state transition from <span><math><msup><mrow><mi>N</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> to <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>. More precisely, (i) for positive correlation degree, the higher intensity of noises may be more likely to induce the state transitions from <span><math><msup><mrow><mi>N</mi></mrow><mrow><mo>∗</mo></mrow></msup></math></span> to <span><math><msub><mrow><mi>N</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>. (ii) Multiplicative and additive noises with negative correlation present a non-monotonic U-shape trend of the probability of state transition, which indicates an antagonistic interaction effect. These findings may provide the theoretical and numerical explanations of the impact of correlated Gaussian color noises on the state transition in the glucose metabolism system and an insight into the mechanism of maintaining long-term euglycemia in a noisy environment.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116536"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lévy-noise-induced wavefront propagation for bistable systems","authors":"Vladimir V. Semenov","doi":"10.1016/j.chaos.2025.116533","DOIUrl":"10.1016/j.chaos.2025.116533","url":null,"abstract":"<div><div>The influence of the Lévy noise’s properties on wavefront propagation is analysed on examples of ensembles of locally coupled bistable oscillators and a single bistable delayed-feedback oscillator considered as a spatially-extended system evolving in quasi-space. It is shown that additive Lévy noise allows to induce wavefront propagation in ensembles of symmetric bistable oscillators. In such a case, the direction and velocity of the noise-sustained propagation is determined both by the noise’s skewness parameter and by the coupling topology (bidirectional and unidirectional coupling schemes are distinguished). In addition, additive Lévy noise induces wavefront propagation in a bistable delayed-feedback oscillator assumed to be symmetric such that its dynamics replicates the collective behaviour in the ensemble with unidirectional coupling. The wavefront propagation velocity used in this analysis is shown to be varied when adjusting the noise parameters. The revealed effects are demonstrated in the ensembles by using numerical simulation, whereas the numerical exploration of the delayed-feedback oscillator is complemented by physical experiments, showing a good correspondence and disclosing thereby the robustness of the observed phenomena.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"198 ","pages":"Article 116533"},"PeriodicalIF":5.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}