International Journal of Bifurcation and Chaos最新文献_第2页

Complex Dynamics of a Discrete Prey–Predator Model Exposing to Harvesting and Allee Effect on the Prey Species with Chaos Control 一个离散猎物-捕食者模型的复杂动力学：猎物物种面临的捕食和混沌控制下的近邻效应

International Journal of Bifurcation and Chaos Pub Date : 2024-07-11 DOI: 10.1142/s0218127424501141

Deniz Elmacı, Figen Kangalgil

引用次数: 0

Combined Impact of Multidelay Feedback Number and Interval: A Novel Mechanism for Controlling the Stability of Stochastic Duffing Systems 多延迟反馈数量和间隔的综合影响：控制随机达芬系统稳定性的新机制

International Journal of Bifurcation and Chaos Pub Date : 2024-07-08 DOI: 10.1142/s0218127424501086

Zhouyu Hu, Zikun Han, Yanling Yang, Qiubao Wang

{"title":"Combined Impact of Multidelay Feedback Number and Interval: A Novel Mechanism for Controlling the Stability of Stochastic Duffing Systems","authors":"Zhouyu Hu, Zikun Han, Yanling Yang, Qiubao Wang","doi":"10.1142/s0218127424501086","DOIUrl":"https://doi.org/10.1142/s0218127424501086","url":null,"abstract":"In this paper, we study a class of nonlinear stochastic Duffing oscillators with multidelay feedback. We propose an effective reduction approach with the help of center manifold theory and stochastic averaging method. Taking the initial time-delay [Formula: see text] as the parameter, we reduce the original system to a one-dimensional averaged Itô equation. Our analysis reveals that the original system exhibits stochastic bifurcations, including stochastic D and P bifurcations. Once we have a clear understanding of the bifurcation structure, we can use this knowledge to choose appropriate system parameters and place the system in the desired state. For instance, by adjusting the initial time-delay [Formula: see text] of the control system, we can stabilize the system and achieve the desired outcome. Numerical simulations also verify the theoretical results. With appropriate parameter choices, multiple time delays can destabilize the equilibrium and promote chaotic behaviors, and can also lead to more stable dynamical behavior. Remarkably, we discovered that increasing the interval of time delays and feedback numbers can enhance system stability. It may potentially serve as a novel mechanism for stabilizing stochastic systems. The study provides a solid theoretical foundation for exploring stochastic systems subject to complex time-delay feedback control, and offers a valuable framework for related fields.","PeriodicalId":506426,"journal":{"name":"International Journal of Bifurcation and Chaos","volume":" 1117","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141668829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Memristor-Based Progressive Hierarchical Conformer Architecture for Speech Emotion Recognition 用于语音情感识别的基于 Memristor 的渐进式分层构形器架构

International Journal of Bifurcation and Chaos Pub Date : 2024-07-05 DOI: 10.1142/s0218127424501177

Tianhao Zhao, Yue Zhou, Xiaofang Hu

{"title":"Memristor-Based Progressive Hierarchical Conformer Architecture for Speech Emotion Recognition","authors":"Tianhao Zhao, Yue Zhou, Xiaofang Hu","doi":"10.1142/s0218127424501177","DOIUrl":"https://doi.org/10.1142/s0218127424501177","url":null,"abstract":"Speech Emotion Recognition (SER) is a challenging task characterized by the diversity and complexity of emotional expression. Due to its powerful feature extraction capabilities, Transformer Network (TN) demonstrates advantages and potential in SER. However, the limited size of available datasets and the difficulty of decoupling emotional features restrain its performance and present challenges in implementing SER on edge devices. To address these issues, we present a Memristor-based Progressive Hierarchical Conformer Architecture (MPCA) and design a conformer submodule that leverages convolution to mitigate TN’s limitations in SER. We propose attention-based feature decoupling, employing hierarchical extraction to decouple speaker characteristics and retain the relevant components, thereby obtaining reliable emotional features. Furthermore, we propose a reconfigurable circuit implementation scheme for MPCA based on operator multiplexing achieving flexible modules that can be dynamically adjusted based on the resources of edge devices, and the stability of the designed circuit is analyzed by simulation experiments with PSPICE. We show that the suggested MPCA demonstrates state-of-the-art performance in SER while significantly reducing system power consumption, offering a solution for SER implementation on edge devices.","PeriodicalId":506426,"journal":{"name":"International Journal of Bifurcation and Chaos","volume":" 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141675497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bifurcation and Instability of a Spatial Epidemic Model 空间流行病模型的分岔与不稳定性

International Journal of Bifurcation and Chaos Pub Date : 2024-07-05 DOI: 10.1142/s0218127424501098

Hailong Yuan, You Zhou, Xiaoyi Yang, Yang Lv, Gaihui Guo

{"title":"Bifurcation and Instability of a Spatial Epidemic Model","authors":"Hailong Yuan, You Zhou, Xiaoyi Yang, Yang Lv, Gaihui Guo","doi":"10.1142/s0218127424501098","DOIUrl":"https://doi.org/10.1142/s0218127424501098","url":null,"abstract":"This paper is concerned with a spatial [Formula: see text] epidemic model with nonlinear incidence rate. First, the existence of the equilibrium is discussed in different conditions. Then the main criteria for the stability and instability of the constant steady-state solutions are presented. In addition, the effect of diffusion coefficients on Turing instability is described. Next, by applying the normal form theory and the center manifold theorem, the existence and direction of Hopf bifurcation for the ordinary differential equations system and the partial differential equations system are given, respectively. The bifurcation diagrams of Hopf and Turing bifurcations are shown. Moreover, a priori estimates and local steady-state bifurcation are investigated. Furthermore, our analysis focuses on providing specific conditions that can determine the local bifurcation direction and extend the local bifurcation to the global one. Finally, the numerical results demonstrate that the intrinsic growth rate, denoted as [Formula: see text], has significant influence on the spatial pattern. Specifically, different patterns appear, with the increase of [Formula: see text]. The obtained results greatly expand on the discovery of pattern formation in the epidemic model.","PeriodicalId":506426,"journal":{"name":"International Journal of Bifurcation and Chaos","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141676397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sliding Homoclinic Bifurcations in a Class of Three-Dimensional Piecewise Affine Systems 一类三维片断仿射系统中的滑动同室分岔

International Journal of Bifurcation and Chaos Pub Date : 2024-07-05 DOI: 10.1142/s0218127424300192

Tiantian Wu, Zhe Zhao, Songmei Huan

引用次数: 0

Modeling the Effect of Informal and Formal Jobs on the Dynamics of Unemployment 模拟非正规工作和正规工作对失业动态的影响

International Journal of Bifurcation and Chaos Pub Date : 2024-07-03 DOI: 10.1142/s0218127424501165

A. K. Misra, Mamta Kumari

{"title":"Modeling the Effect of Informal and Formal Jobs on the Dynamics of Unemployment","authors":"A. K. Misra, Mamta Kumari","doi":"10.1142/s0218127424501165","DOIUrl":"https://doi.org/10.1142/s0218127424501165","url":null,"abstract":"The limited availability of formal jobs in developing nations always heightens the challenge for unemployed individuals in securing regular employment. Temporary employment in the informal sector serves as a source to fulfill their basic needs and enhance their employable skills. In this paper, we introduce a nonlinear mathematical model to study the effect of informal and formal jobs on the dynamics of unemployment. For the model formulation, we categorize the labor force into three classes: unemployed, temporary employed, and regularly employed. A separate dynamical variable is used to represent the available temporary vacancies. It is assumed that temporarily employed individuals may transition into regular employment or self-employment. Furthermore, self-employed individuals contribute to generating temporary vacancies within the informal sector. The long-term behavior of the proposed system is analyzed using the qualitative theory of differential equations. A quantity known as the reproduction number of the system is derived, and it is found that the occurrence of multiple bifurcations for the proposed system is influenced by the value of this threshold quantity. Furthermore, we validate our analytical findings numerically. The findings of this study illustrate that an increase in the shifting rate of individuals from temporary to regular employment is not always effective in increasing the number of regularly employed individuals. Additionally, an increase in the transition of temporarily employed individuals into self-employment, coupled with their involvement in creating more temporary jobs, proves beneficial in reducing unemployment.","PeriodicalId":506426,"journal":{"name":"International Journal of Bifurcation and Chaos","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141682324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Some Interesting Bifurcation Phenomena in the Generalized KdV–mKdV-Like Equation 广义 KdV-mKdV 类似方程中一些有趣的分岔现象

International Journal of Bifurcation and Chaos Pub Date : 2024-07-03 DOI: 10.1142/s0218127424501189

Yiren Chen, Yan Liang, Xuefeng Gao, Si Chen, Yu Han

引用次数: 0

Chaotic Dynamic Behavior of a Fractional-Order Financial System with Constant Inelastic Demand 具有恒定非弹性需求的分数阶金融系统的混沌动态行为

International Journal of Bifurcation and Chaos Pub Date : 2024-07-03 DOI: 10.1142/s0218127424501116

Xiao-Long Gao, Zhiyuan Li, Yu-Lan Wang

引用次数: 0

Hopf Bifurcation and Turing Instability of a Delayed Diffusive Zooplankton–Phytoplankton Model with Hunting Cooperation 具有狩猎合作的延迟扩散浮游动物-浮游植物模型的霍普夫分岔和图灵不稳定性

International Journal of Bifurcation and Chaos Pub Date : 2024-06-07 DOI: 10.1142/s0218127424500901

Xin-You Meng, Li Xiao

引用次数: 0

Local and Global Dynamics of a Ratio-Dependent Holling–Tanner Predator–Prey Model with Strong Allee Effect 具有强阿利效应的依赖比率的霍林-坦纳捕食者-猎物模型的局部和全局动态变化

International Journal of Bifurcation and Chaos Pub Date : 2024-06-07 DOI: 10.1142/s0218127424500925

Weiping Lou, Pei Yu, Jia-Fang Zhang, Claudio Arancibia-Ibarra

引用次数: 0