Chaos Solitons & Fractals最新文献

英文中文

Periodic and time-mean fluctuating heat transfer of Darcy nanofluid along nonlinear radiating plate with heat source/sink and oscillatory amplitude conditions

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-03 DOI: 10.1016/j.chaos.2025.116229

Serhan Alshammari , Zia Ullah , Md. Mahbub Alam , Mohamed Boujelbene , Ahmed Osman Ibrahim , Hanaa Abu-Zinadah

Influence of microgravity, heat source/sink, and nonlinear thermal radiation on Darcy Forchheimer nanofluid over vertical radiating plate is the prominent objective of this study. The effects of heat source and heat sink are prominently useful in cooling of electronic devices, polymer industry, metallic plates, optical fibers and pipe industry. Non-dimensional analysis is performed for governing model and converted into steady, real and imaginary form. Reduced models are elaborated numerically using implicit finite difference method, primitive transformation and Gaussian elimination scheme. The influence of governing parameters on fluid velocity, surface temperature, steady heat-mass rate, oscillatory skin friction and oscillatory heat-mass transfer is discussed geometrically. Form numerical results, it is observed that the variation in heat source and heat sink has prominent effect on steady and oscillatory outcomes. Enhancing amplitude in fluid velocity, surface temperature and concentration profile is recorded for microgravity and thermal radiation parameter with heat source. Decreasing behavior of steady results is reported with heat sink effects. Steady skin friction and mass transfer is enhanced for thermophoresis and heat source effects. For both Brownian and thermophoresis parameters, the steady heating rate is increased with heat sink impact. Prominent oscillating layer in the amplitude of heat and mass transfer is recorded for high Prandtl and Schmidt number. Lower amplitude with smaller oscillating frequency of skin-friction, heat and mass transmission is found for small Schmidt and Prandtl value.

{"title":"Periodic and time-mean fluctuating heat transfer of Darcy nanofluid along nonlinear radiating plate with heat source/sink and oscillatory amplitude conditions","authors":"Serhan Alshammari , Zia Ullah , Md. Mahbub Alam , Mohamed Boujelbene , Ahmed Osman Ibrahim , Hanaa Abu-Zinadah","doi":"10.1016/j.chaos.2025.116229","DOIUrl":"10.1016/j.chaos.2025.116229","url":null,"abstract":"<div><div>Influence of microgravity, heat source/sink, and nonlinear thermal radiation on Darcy Forchheimer nanofluid over vertical radiating plate is the prominent objective of this study. The effects of heat source and heat sink are prominently useful in cooling of electronic devices, polymer industry, metallic plates, optical fibers and pipe industry. Non-dimensional analysis is performed for governing model and converted into steady, real and imaginary form. Reduced models are elaborated numerically using implicit finite difference method, primitive transformation and Gaussian elimination scheme. The influence of governing parameters on fluid velocity, surface temperature, steady heat-mass rate, oscillatory skin friction and oscillatory heat-mass transfer is discussed geometrically. Form numerical results, it is observed that the variation in heat source and heat sink has prominent effect on steady and oscillatory outcomes. Enhancing amplitude in fluid velocity, surface temperature and concentration profile is recorded for microgravity and thermal radiation parameter with heat source. Decreasing behavior of steady results is reported with heat sink effects. Steady skin friction and mass transfer is enhanced for thermophoresis and heat source effects. For both Brownian and thermophoresis parameters, the steady heating rate is increased with heat sink impact. Prominent oscillating layer in the amplitude of heat and mass transfer is recorded for high Prandtl and Schmidt number. Lower amplitude with smaller oscillating frequency of skin-friction, heat and mass transmission is found for small Schmidt and Prandtl value.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"194 ","pages":"Article 116229"},"PeriodicalIF":5.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529191","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}

引用次数: 0

Heterogeneous Hopfield neural network with analog implementation

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-03 DOI: 10.1016/j.chaos.2025.116234

Bocheng Bao, Chunlong Zhou, Han Bao, Bei Chen, Mo Chen

The activation function plays a crucial role as a nonlinear factor in the Hopfield neural network. However, limited attention has been given to studying heterogeneous activation functions. In this study, we present a three-neuron heterogeneous Hopfield neural network incorporating two distinct activation functions, namely hyperbolic tangent function and sine function. The kinetics of the heterogeneous neural network is investigated theoretically and numerically, and the kinetic effect of the sine activation function is revealed thereby. The findings demonstrate the presence of intricate kinetics, including chaos, period, stable point, and coexisting attractors, and the enlargement of chaotic kinetics distribution on the parameter plane by sine activation function within the heterogeneous neural network. Notably, an analog circuit is designed on a hardware level to simplify the implementation of the heterogeneous Hopfield neural network and experimental measurements provide strong validation for the numerical findings.

引用次数: 0

Generalized kinetic theory of coarse-grained systems. II. Comparison of various approximations and coarse-grainings

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-02 DOI: 10.1016/j.chaos.2025.116093

Bernard Gaveau, Michel Moreau

In the first part of this article, recently published, the general kinetic theory of coarse-grained systems has been presented in the abstract formalism of communication theory developed by Shannon, Khinchin, Kolmogorov and other authors. In the second part of the article, presented below, we compare various approximations of this theory, and several kinds of coarse-grainings, focusing on their asymptotics. In particular, we introduce extensions of classical ergodic theorems and derive some rigorous results which allow for such comparison, although explicit calculations may be problematic.

在最近发表的这篇文章的第一部分中，我们用香农（Shannon）、钦钦（Khinchin）、科尔莫戈罗夫（Kolmogorov）和其他作者提出的通信理论的抽象形式主义，介绍了粗粒度系统的一般动力学理论。在下文第二部分中，我们将比较这一理论的各种近似值和几种粗粒度，重点关注它们的渐近性。我们特别介绍了经典遍历定理的扩展，并推导出一些严格的结果，从而可以进行这种比较，尽管明确的计算可能会有问题。

引用次数: 0

Stability, convergence, and energy preservation robust methods for fully implicit and fully explicit coupling schemes

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-01 DOI: 10.1016/j.chaos.2025.116131

Taj Munir , Can Kang , Hongchu Chen , Hussan Zeb , Muhammad Naveed Khan , Muhammad Usman Farid

This paper presents an analysis of the Godunov–Ryabenkii stability, Generalized Mini-mal Residual(GMRES) convergence, and energy-preserving properties of partitioned and monolithic approaches (fully implicit and fully explicit schemes) for solving coupled parabolic problems. Specifically, we consider a bi-domain parabolic diffusion problem with two types of coupling conditions at the interface: Dirichlet–Neumann and heat-flux coupling. Our findings shows that the Dirichlet–Neumann coupling is unconditionally stable for both approaches. In contrast, the heat-flux coupling requires additional conditions to ensure the stability of the coupled problem. For numerical approximations, finite volume and finite difference schemes are used. The results show that energy preservation is achieved with one-sided differences in the finite volume method, while the finite difference method achieves conservation when central difference approximations are used for both the coupling and boundary conditions in the heat-flux coupling case. Additionally, Dirichlet–Neumann coupling maintains stability and energy preservation in both methods using the one-sided approach without requiring extra conditions. However, for heat-flux coupling, an additional restriction is necessary to ensure stability. The challenge for the convergence of coupled interface problems arise due to strong domain interactions and sensitive interface conditions, like Dirichlet–Neumann or heat-flux coupling. The poor system conditioning and discretization choices can slow the rate of convergence. For this purpose we used the GMRES method. This work provides a comprehensive framework for addressing coupled parabolic diffusion problems using robust, stable, and energy-preserving numerical methods.

{"title":"Stability, convergence, and energy preservation robust methods for fully implicit and fully explicit coupling schemes","authors":"Taj Munir , Can Kang , Hongchu Chen , Hussan Zeb , Muhammad Naveed Khan , Muhammad Usman Farid","doi":"10.1016/j.chaos.2025.116131","DOIUrl":"10.1016/j.chaos.2025.116131","url":null,"abstract":"<div><div>This paper presents an analysis of the Godunov–Ryabenkii stability, Generalized Mini-mal Residual(GMRES) convergence, and energy-preserving properties of partitioned and monolithic approaches (fully implicit and fully explicit schemes) for solving coupled parabolic problems. Specifically, we consider a bi-domain parabolic diffusion problem with two types of coupling conditions at the interface: Dirichlet–Neumann and heat-flux coupling. Our findings shows that the Dirichlet–Neumann coupling is unconditionally stable for both approaches. In contrast, the heat-flux coupling requires additional conditions to ensure the stability of the coupled problem. For numerical approximations, finite volume and finite difference schemes are used. The results show that energy preservation is achieved with one-sided differences in the finite volume method, while the finite difference method achieves conservation when central difference approximations are used for both the coupling and boundary conditions in the heat-flux coupling case. Additionally, Dirichlet–Neumann coupling maintains stability and energy preservation in both methods using the one-sided approach without requiring extra conditions. However, for heat-flux coupling, an additional restriction is necessary to ensure stability. The challenge for the convergence of coupled interface problems arise due to strong domain interactions and sensitive interface conditions, like Dirichlet–Neumann or heat-flux coupling. The poor system conditioning and discretization choices can slow the rate of convergence. For this purpose we used the GMRES method. This work provides a comprehensive framework for addressing coupled parabolic diffusion problems using robust, stable, and energy-preserving numerical methods.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"194 ","pages":"Article 116131"},"PeriodicalIF":5.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527479","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}

引用次数: 0

Reservoir computing system using discrete memristor for chaotic temporal signal processing

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-01 DOI: 10.1016/j.chaos.2025.116230

Yue Deng , Shuting Zhang , Fang Yuan , Yuxia Li , Guangyi Wang

Reservoir computing (RC) is a highly efficient neural network for processing temporal signals, primarily due to its significantly lower training cost compared to standard recurrent neural networks. In this work, a novel discrete memristor (DM) model is investigated and a simple two-dimensional chaotic map based on the DM model is presented, in which complex dynamics are simulated. By utilizing this DM-based map as a reservoir, a dynamic DM-based RC system is constructed, and the performance is verified through nonlinear regression and time-series prediction tasks. Our system achieves a high accuracy rate of 99.99 % in the nonlinear recognitions, as well as a low root mean square error of 0.0974 in the time-series prediction of the Logistic map. This work may pave the way for the future development of high-efficiency memristor-based RC systems to handle more complex temporal tasks.

储层计算（RC）是一种处理时间信号的高效神经网络，主要原因是它的训练成本比标准递归神经网络低得多。在这项工作中，研究了一种新型离散忆阻器（DM）模型，并提出了一种基于 DM 模型的简单二维混沌图，其中模拟了复杂的动力学。利用这个基于 DM 的地图作为储库，构建了一个基于 DM 的动态 RC 系统，并通过非线性回归和时间序列预测任务验证了其性能。我们的系统在非线性识别中实现了 99.99 % 的高准确率，在 Logistic 地图的时间序列预测中实现了 0.0974 的低均方根误差。这项工作可能会为未来开发基于忆阻器的高效 RC 系统处理更复杂的时间任务铺平道路。

引用次数: 0

Model reference adaptive control of the nonlinear fractional order – stochastic model of the corona virus

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-03-01 DOI: 10.1016/j.chaos.2025.116225

Abedin Ranjbar , Ali Madady , Mehdi Ramezani , Alireza Khosravi

In this paper, the Model Reference Adaptive Control (MRAC) method along with a state feedback controller is employed for synchronizing NFSCV, a complex nonlinear fractional-order stochastic model of the coronavirus. MRAC is a methodology that combines both linear feedback controllers and adaptive law techniques for designing a simple but robust adaptive feedback system. We have added a stochastic noise term to the coronavirus model representing sudden mutations and external disturbances. Also, we will implement the realization of fractional-order differential equations, and it gives us a real representation of the virus. In this paper, we address the question of when the controlled model 'infective or slave system' states can be observed and tuned to the master or reference model 'healthy and vaccination' states for our objective functions attempting a minimization between tracking errors of the states of master and slave systems, variance, and squared error integrals. In this paper, we further show that the system is asymptotically stable using the stochastic analysis along with Lyapunov theory. Through these simulations, we are able to see that by using our control algorithm, the infected individuals can be driven to follow a trajectory close to the one followed by the vaccinated individuals.

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引用次数: 0

On the dynamics of coupled envelope structures for barotropic–baroclinic interaction with Bottom Topography

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-02-28 DOI: 10.1016/j.chaos.2025.116179

Jie Wang, Ruigang Zhang, Quansheng Liu, Liangui Yang

Nonlinear barotropic–baroclinic interaction is of great theoretical importance in gaining a deeper understanding of the physical mechanisms of atmospheric or oceanic motions. Based on the classical two-layer quasi-geostrophic potential vorticity (2LQGPV) conservation model, this paper derives the nonlinear Schrödinger equation describing the Rossby wave amplitude evolution under the

β

-plane approximation, combined with multiscale analysis and small-parameter expansion methods. The influence of different forms of bottom topography on the evolution mechanism of the nonlinear barotropic–baroclinic interaction and the blockage effect is highlighted. The results show that the barotropic stream function dominates the generation process of the baroclinic stream function, and at the same time the baroclinic stream function has a perturbing effect on the barotropic stream function. Topography is an essential factor for dipole excitation or decay, with up-convex topography more likely to cause dipole blockage, while sloped topography and down-concave topography have a weaker effect. This finding reveals the significant influence of topography in wave–wave interactions. These results further enrich the theory of nonlinear barotropic–baroclinic interactions and provide a new theoretical framework and explanation for understanding wave–wave and wave-stream interactions.

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引用次数: 0

Influences of the graphene reinforcements on the natural vibrational properties, nonlinear flutter responses, and the chaotic motions of the FG-GR laminated composite cantilever rectangular variable cross-section plate in the supersonic flow

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-02-28 DOI: 10.1016/j.chaos.2025.116221

Y. Jiang , Y. Wang , W. Zhang , Y.F. Zhang , S.F. Lu , X. Du

Due to the excellent mechanical and lightweight properties of the graphene-reinforced composite structure, it can meet the design requirements of modern aircraft comments. In this paper, the aircraft wings with low aspect ratio are modelled as the functionally graded graphene-reinforced laminated composite cantilever rectangular (FG-GRLCCR) variable cross-section plate. The influences of the graphene reinforcements on the natural vibrational properties, the nonlinear flutter responses, and the chaotic motions of the FG-GRLCCR variable cross-section plate are investigated. The extended Halpin-Tsai model is used to calculate the mechanical parameters for the graphene-reinforced composite materials. The first-order piston theory is applied to simulate the aerodynamic force on the FG-GRLCCR variable cross-section plate in supersonic flow. Considering the classical laminated theory, the von Karman large deformation theory, and the simple harmonic excitation, the dynamic partial differential equations for the FG-GRLCCR variable cross-section plate are derived by the Hamilton principle. The nonlinear ordinary partial equations of the system are given based on the Galerkin truncation technique. The frequency loci veering phenomenon and vibrational mode interaction for the FG-GRLCCR variable cross-section plate are obtained by the Rayleigh-Ritz method. The nonlinear flutter responses of the FG-GRLCCR variable cross-section plate are analyzed before and after critical flutter pressure. The bifurcation diagrams, Maximum Lyapunov exponent diagram, phase diagram, waveform diagram, and Poincaré cross-section diagram of the system are depicted for investigating the influence the graphene reinforcements on the nonlinear dynamic responses. The results showed that the graphene reinforcements and distributed patterns can change the frequency loci veering phenomenon, improve the critical flutter pressure and reduce the occurrence of chaotic motions of the FG-GRLCCR variable cross-section plate.

{"title":"Influences of the graphene reinforcements on the natural vibrational properties, nonlinear flutter responses, and the chaotic motions of the FG-GR laminated composite cantilever rectangular variable cross-section plate in the supersonic flow","authors":"Y. Jiang , Y. Wang , W. Zhang , Y.F. Zhang , S.F. Lu , X. Du","doi":"10.1016/j.chaos.2025.116221","DOIUrl":"10.1016/j.chaos.2025.116221","url":null,"abstract":"<div><div>Due to the excellent mechanical and lightweight properties of the graphene-reinforced composite structure, it can meet the design requirements of modern aircraft comments. In this paper, the aircraft wings with low aspect ratio are modelled as the functionally graded graphene-reinforced laminated composite cantilever rectangular (FG-GRLCCR) variable cross-section plate. The influences of the graphene reinforcements on the natural vibrational properties, the nonlinear flutter responses, and the chaotic motions of the FG-GRLCCR variable cross-section plate are investigated. The extended Halpin-Tsai model is used to calculate the mechanical parameters for the graphene-reinforced composite materials. The first-order piston theory is applied to simulate the aerodynamic force on the FG-GRLCCR variable cross-section plate in supersonic flow. Considering the classical laminated theory, the von Karman large deformation theory, and the simple harmonic excitation, the dynamic partial differential equations for the FG-GRLCCR variable cross-section plate are derived by the Hamilton principle. The nonlinear ordinary partial equations of the system are given based on the Galerkin truncation technique. The frequency loci veering phenomenon and vibrational mode interaction for the FG-GRLCCR variable cross-section plate are obtained by the Rayleigh-Ritz method. The nonlinear flutter responses of the FG-GRLCCR variable cross-section plate are analyzed before and after critical flutter pressure. The bifurcation diagrams, Maximum Lyapunov exponent diagram, phase diagram, waveform diagram, and Poincaré cross-section diagram of the system are depicted for investigating the influence the graphene reinforcements on the nonlinear dynamic responses. The results showed that the graphene reinforcements and distributed patterns can change the frequency loci veering phenomenon, improve the critical flutter pressure and reduce the occurrence of chaotic motions of the FG-GRLCCR variable cross-section plate.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"194 ","pages":"Article 116221"},"PeriodicalIF":5.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520049","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}

引用次数: 0

A parameter estimation method for neural mass model based on the improved chimp optimization algorithm and Riemannian geometry

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-02-28 DOI: 10.1016/j.chaos.2025.116219

Shaoting Yan , Xiaochu Shi , Ruiqi Li , Lipeng Zhang , Rui Zhang , Mingming Chen , Meng Li , Hui Zhang , Runtao Li , Li Shi , Yuxia Hu

Neural mass model (NMM) serves as an effective tool for understanding and exploring the complex dynamics of brain systems. Accurately estimating the model parameters of NMM is highly important for building brain models driven by observed electroencephalogram (EEG) data. However, existing methods for comparing model output with observed data primarily focus on one-dimensional linear comparisons, overlooking the high-dimensional nonlinear dynamics and Riemannian geometry characteristics of EEG data. To address this issue, we propose a novel parameter estimation method for NMM based on the improved chimp optimization algorithm (ChOA) and Riemannian geometry. First, ChOA is improved by incorporating the Aquila optimizer (AOChOA) is used to improve the convergence efficiency and accuracy of the nonlinear optimization problem. Then, a novel loss function based on the Riemannian geometry of symmetric positive definite matrices (LRSPD) is constructed to capture the high-dimensional nonlinear dynamics of EEG signals. Finally, we validate the effectiveness of the proposed method by using the model output with fixed model parameters and real EEG signals as observed data, respectively. When using the model output with fixed model parameters, the loss function LRSPD yielded more accurate parameter estimation results compared to others, with the fitted model closely matching the dynamics of the observed data. When using real EEG data, the proposed method successfully recovered differences in EEG dynamics for subjects at different consciousness levels. Additionally, our study reveals the neural mechanisms of decreased consciousness level in patients with disorders of consciousness (DOC), characterized by increased inhibitory neural activity of the brain.

{"title":"A parameter estimation method for neural mass model based on the improved chimp optimization algorithm and Riemannian geometry","authors":"Shaoting Yan , Xiaochu Shi , Ruiqi Li , Lipeng Zhang , Rui Zhang , Mingming Chen , Meng Li , Hui Zhang , Runtao Li , Li Shi , Yuxia Hu","doi":"10.1016/j.chaos.2025.116219","DOIUrl":"10.1016/j.chaos.2025.116219","url":null,"abstract":"<div><div>Neural mass model (NMM) serves as an effective tool for understanding and exploring the complex dynamics of brain systems. Accurately estimating the model parameters of NMM is highly important for building brain models driven by observed electroencephalogram (EEG) data. However, existing methods for comparing model output with observed data primarily focus on one-dimensional linear comparisons, overlooking the high-dimensional nonlinear dynamics and Riemannian geometry characteristics of EEG data. To address this issue, we propose a novel parameter estimation method for NMM based on the improved chimp optimization algorithm (ChOA) and Riemannian geometry. First, ChOA is improved by incorporating the Aquila optimizer (AOChOA) is used to improve the convergence efficiency and accuracy of the nonlinear optimization problem. Then, a novel loss function based on the Riemannian geometry of symmetric positive definite matrices (LRSPD) is constructed to capture the high-dimensional nonlinear dynamics of EEG signals. Finally, we validate the effectiveness of the proposed method by using the model output with fixed model parameters and real EEG signals as observed data, respectively. When using the model output with fixed model parameters, the loss function LRSPD yielded more accurate parameter estimation results compared to others, with the fitted model closely matching the dynamics of the observed data. When using real EEG data, the proposed method successfully recovered differences in EEG dynamics for subjects at different consciousness levels. Additionally, our study reveals the neural mechanisms of decreased consciousness level in patients with disorders of consciousness (DOC), characterized by increased inhibitory neural activity of the brain.</div></div>","PeriodicalId":9764,"journal":{"name":"Chaos Solitons & Fractals","volume":"194 ","pages":"Article 116219"},"PeriodicalIF":5.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511413","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}

引用次数: 0

Some mixed soliton wave interaction patterns and stabilities for Rabi-coupled nonlocal Gross–Pitaevskii equations

IF 5.3 1区数学 Q1 MATHEMATICS, INTERDISCIPLINARY APPLICATIONS

Chaos Solitons & Fractals

Pub Date : 2025-02-28 DOI: 10.1016/j.chaos.2025.116171

Li Li, Fajun Yu

Some mixed interactions of the soliton, breather and rogue wave(RW) formations and their dynamics are studied in Rabi-coupled Bose–Einstein condensates(BECs) with spatially varying dispersion and nonlinearity. We consider the 2-component inhomogeneous Rabi-coupled Gross–Pitaevskii (GP) equations through suitable three kinds of rotational and similarity transformations. The effects of inhomogeneity and optical lattice hyperbolic potentials of the RWs are investigated with two different forms of potential strengths, and some oscillating behaviors of dark–bright solitons, RWs and breather solitons with Rabi coupling terms are shown in 2-component condensates. We demonstrate creation of some RWs coexisting with dark–bright soliton part in second component of the 2-component GP equations. We show that some mixed interactions of vector soliton, breather and RW formations by employing parabolic cylinder modulations, and find a striking feature of Rabi coupling with spatial modulation. Further, the RWs can be converted into broad based zero background RW appearing on the top of a bright soliton by introducing spatial modulation in 2-component systems. Some dynamic behaviors of the RW solutions are investigated analytically with the external potentials, and the mixed waves, interaction patterns and stabilities for Rabi-coupled nonlocal GP systems are presented with modulation instability, which can be used to calculate nonautonomous mixed wave interactions and the potential applications for the RW phenomena.

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