Article
Automation & Control Systems
Liang Feng, Juan Yu, Cheng Hu, Chengdong Yang, Haijun Jiang
Summary: This article addresses the synchronization issue in finite and fixed time for fully complex-variable delayed neural networks with discontinuous activations and time-varying delays. By introducing a complex-valued sign function and developing two discontinuous control strategies, synchronization criteria and estimates of settling time are derived using nonsmooth analysis and novel inequality techniques in the complex field. The unified control strategy designed under a new norm framework reveals that a parameter value in the controller determines whether the networks synchronize in finite or fixed time, supported by numerical results for an example provided in the article.
IEEE TRANSACTIONS ON CYBERNETICS
(2021)
Article
Computer Science, Theory & Methods
Lian Duan, Min Shi, Lihong Huang
Summary: This paper studies the finite-/fixed-time synchronization problem for delayed diffusive Hopfield neural networks and designs a novel state feedback controller using Filippov regularization approaches, inequality techniques, and a generalized stability theorem. The theoretical results obtained generalize and improve existing literature, and a numerical example is presented to demonstrate the effectiveness of the results.
FUZZY SETS AND SYSTEMS
(2021)
Article
Computer Science, Artificial Intelligence
Ruoyu Wei, Jinde Cao, Sergey Gorbachev
Summary: This paper focuses on the fixed-time synchronization control of quaternion-valued memristive neural networks (QVMNNs). By decomposing the QVMNNs model into four real-valued systems and designing discontinuous control schemes based on the sign function, novel criteria for fixed-time synchronization are derived using nonsmooth analysis and inequality techniques.
COGNITIVE COMPUTATION
(2023)
Article
Engineering, Multidisciplinary
Xiaona Song, Jingtao Man, Choon Ki Ahn, Shuai Song
Summary: This paper explores a novel class of nonlinear interconnected neural networks in the complex domain, obtaining a finite/fixed-time synchronization criterion for N subsystems with the design of a suitable nonlinear controller. The criteria for synchronization in finite time and fixed time are integrated into a unified theorem, and a secret communication example is presented to verify the validity and practicability of the research.
IEEE TRANSACTIONS ON NETWORK SCIENCE AND ENGINEERING
(2021)
Article
Mathematics, Interdisciplinary Applications
Lian Duan, Jinzhi Liu, Chuangxia Huang, Zengyun Wang
Summary: This paper focuses on the finite-/fixed-time anti-synchronization (FFTAS) problem of neural networks with leakage delays under discontinuous disturbances. By designing new negative exponential controllers and using Fillipov's theory and the Lyapunov functional method, novel FFTAS criteria are established for the considered drive-response network systems, and the corresponding settling time is estimated. The established theoretical results extend and cover the existing ones, and a numerical example is provided to verify the practicality of the obtained results.
CHAOS SOLITONS & FRACTALS
(2022)
Article
Mathematics, Interdisciplinary Applications
Liang Feng, Cheng Hu, Juan Yu, Haijun Jiang, Shiping Wen
Summary: This article introduces a new theorem for fixed-time stability, simplifies control laws for complex-valued neural networks through the complex-valued sign function framework, and obtains synchronization conditions for coupled complex-valued neural networks using the theory of complex-variable functions and improved stability.
CHAOS SOLITONS & FRACTALS
(2021)
Article
Computer Science, Artificial Intelligence
Qintao Gan, Liangchen Li, Jing Yang, Yan Qin, Mingqiang Meng
Summary: This article introduces new methods for synchronization in memristive complex-valued neural networks within fixed time and preassigned time, optimizing synchronization results by introducing different norms of complex numbers and new control strategies, with numerical simulations demonstrating the effectiveness of the proposed methodology.
IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS
(2022)
Article
Computer Science, Information Systems
Yanli Huang, Fang Wu
Summary: The paper discusses the finite-time passivity and synchronization issues for two categories of coupled complex-valued memristive neural networks with and without time-varying delay. It proposes conditions and criteria for finite-time passivity and synchronization, and validates the results with numerical examples.
INFORMATION SCIENCES
(2021)
Article
Computer Science, Artificial Intelligence
Tao Peng, Yanqiu Wu, Zhengwen Tu, A. S. Alofi, Jianquan Lu
Summary: A control strategy based on Lyapunov functions is proposed for the fixed-time synchronization of a time-delay quaternion-valued neural network (QVNN). This strategy is further extended to the prescribed-time synchronization of the QVNN. Another improved two-step switching control strategy is also proposed based on this flexible control strategy. Numerical examples demonstrate the advantages of the proposed methods.
Article
Mathematics
Wanlu Wei, Cheng Hu, Juan Yu, Haijun Jiang
Summary: This article investigates fixed-time synchronization and preassigned-time synchronization for quaternion-valued neural networks with time-varying delays and discontinuous activation functions. A direct analytical method is proposed to design quaternion-valued controllers for fixed-time synchronization, based on the quaternion-valued signum function and related properties. Moreover, preassigned-time synchronization is explored using quaternion-valued control design with preassigned synchronization time and finite control gains. Compared to existing methods, the direct method without separation presented in this article simplifies theoretical analysis, and the proposed quaternion-valued control schemes are simpler and more effective than traditional designs. Two numerical examples are provided to support the theoretical results.
ACTA MATHEMATICA SCIENTIA
(2023)
Article
Mathematics, Applied
Yanli Huang, Limei Su
Summary: This paper investigates the general decay anti-synchronization problem and H infinity general decay anti-synchronization problem for coupled reaction-diffusion complex-valued memristive neural networks with and without time delays. The concept of general decay H infinity anti-synchronization under the complex-valued case is introduced, followed by the proof of a crucial lemma which provides a new sufficient condition for achieving general decay anti-synchronization in complex field. By using this lemma and designing a suitable nonlinear feedback controller, criteria for realizing general decay anti-synchronization are established for both cases. Numerical examples are provided to validate the effectiveness of the anti-synchronization results.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Engineering, Mechanical
Runan Guo, Junwei Lu, Yongmin Li, Wenshun Lv
Summary: This paper investigates the problem of fixed-time synchronization for delayed complex-valued neural networks with inertial term, proposing two different controllers that can achieve perfect synchronization in a fixed time for networks with different types of activation functions. Synchronization criteria in terms of matrix inequalities and estimates of the settling times are derived, utilizing innovative inequalities in the complex field, representing an advancement of existing research progress. Numerical simulations for various types of activation functions are provided to support the theoretical results.
NONLINEAR DYNAMICS
(2021)
Article
Automation & Control Systems
Chaouki Aouiti, Mayssa Bessifi
Summary: This article focuses on the synchronization of fuzzy Clifford-valued Cohen-Grossberg neural networks with discontinuous activations and time-varying delays. Effective conditions and a novel fixed-time convergence method are derived to ensure synchronization, with estimated settling times provided. Numerical examples with simulations confirm the effectiveness of the proposed synchronization criteria.
INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING
(2021)
Article
Mathematics, Applied
Changqing Long, Guodong Zhang, Junhao Hu
Summary: This paper investigates the problem of p-norm fixed-time synchronization for a class of delayed inertial complex-valued neural networks, establishing new algebraic criteria using non-smooth Lyapunov function and inequality analytical techniques. The settling time of synchronization is theoretically estimated and simulations demonstrate the validity and availability of the results.
APPLIED MATHEMATICS AND COMPUTATION
(2021)
Article
Computer Science, Artificial Intelligence
Zengyun Wang, Jinde Cao, Zuowei Cai, Xuegang Tan, Rensi Chen
Summary: This study investigates the issue of finite-time synchronization of discontinuous reaction-diffusion neural networks with time-varying coefficients. The effects caused by discontinuous activations are handled by differential inclusion theory, and a relaxed Lyapunov function method is introduced to design control algorithms to achieve finite-time synchronization. The results are substantiated by two numerical simulations.
Article
Computer Science, Interdisciplinary Applications
Chuangxia Huang, Renli Su, Jinde Cao, Songlin Xiao
MATHEMATICS AND COMPUTERS IN SIMULATION
(2020)
Article
Mathematics, Interdisciplinary Applications
Jinde Cao, Usman Ali, Muhammad Javaid, Chuangxia Huang
Article
Mathematics, Applied
Chuangxia Huang, Xin Long, Jinde Cao
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2020)
Article
Mathematics, Applied
Anbalagan Pratap, Ramachandran Raja, Jehad Alzabut, Jinde Cao, Grienggrai Rajchakit, Chuangxia Huang
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2020)
Article
Mathematics, Applied
Ruoyu Wei, Jinde Cao, Chuangxia Huang
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2020)
Article
Mathematics, Applied
Anbalagan Pratap, Ramachandran Raja, Jinde Cao, Chuangxia Huang, Michal Niezabitowski, Ovidiu Bagdasar
Summary: The dynamics of discrete-time neural networks in fractional-order cases are documented for the first time in this manuscript. The manuscript focuses on the stability criterion of discrete-time fractional-order complex-valued neural networks with time delays, providing sufficient criteria and a global Mittag-Leffler stability criterion. Computer simulations of numerical examples demonstrate the correctness and effectiveness of the presented stability results.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Mathematics
Chuangxia Huang, Yanxiang Tan
Summary: This paper explores the global behavior of a reaction-diffusion system describing bacterial infection in a population, considering the pathogens' incubation period. The study uses operator semigroup theory and dynamical system approaches to investigate the global dynamics with respect to the homogeneous Dirichlet problem. The analysis includes the positivity, boundedness, topology, permanence, and threshold dynamics for special models with different infectivity nonlinearities.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Multidisciplinary Sciences
Chuangxia Huang, Jian Zhang, Jinde Cao
Summary: This paper investigates the influence of delay on global attractivity in a tick population dynamics model with two distinctive time-varying delays. By using differential inequality techniques and the fluctuation lemma, the study proves the persistence and positiveness of all solutions in the equation, and derives a delay-dependent criterion for global attractivity of the positive equilibrium point. Numerical simulations are presented to verify the improved and complementary results.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2021)
Article
Business, Finance
Chuangxia Huang, Yunke Deng, Xiaoguang Yang, Jinde Cao, Xin Yang
Summary: This paper uses a complex network approach to study the interrelationships between individual stocks in the Chinese stock market, revealing the long-term investment value of stocks, driving factors, and the impact factors of the comovement structure. It is worth noting that the relationships between these influencing factors may change during crisis periods.
INTERNATIONAL REVIEW OF FINANCIAL ANALYSIS
(2021)
Article
Computer Science, Interdisciplinary Applications
Chuangxia Huang, Bingwen Liu, Chaofan Qian, Jinde Cao
Summary: This article examines a class of high-order proportional delayed cellular neural networks incorporating D operator, confirming the boundedness and global existence of positive solutions, and establishing conditions for the positivity and global exponential stability of pseudo almost periodic solutions of the models. A numerical example is provided to validate the effectiveness and feasibility of the theoretical findings. (C) 2021 International Association for Mathematics and Computers in Simulation (IMACS). Published by Elsevier B.V. All rights reserved.
MATHEMATICS AND COMPUTERS IN SIMULATION
(2021)
Article
Multidisciplinary Sciences
Wenke Wang, Le Li, Xuejun Yi, Chuangxia Huang
Summary: This paper focuses on neutral functional differential equations in population dynamics and analyzes the convergence behavior and the subtle relations of the omega-limited set and special point through monotonicity techniques and functional methods. The results show that every bounded solution converges to a constant vector as t tends to positive infinity, which also leads to an improved Haddock conjecture.
Article
Business, Finance
Xin Yang, Cheng Jin, Chuangxia Huang, Xiaoguang Yang
Summary: This article examines the effect of the Engle-Granger (E-G) price spillover network characteristics on firm's stock liquidity using a longitudinal dataset of FTSE 350 from 2006 to 2021. The study finds that the subprime crisis, European debt sovereign crisis, British Brexit, and COVID-19 caused significant changes in the network structure. It also reveals that firms with higher centrality are more likely to experience price shocks, leading to lower stock liquidity. Additionally, the study establishes a general framework for network characteristics and stock liquidity to some extent.
FINANCE RESEARCH LETTERS
(2023)
Article
Mathematics
Chuangxia Huang, Jianhong Wu
Summary: We argue that self-regulation in tick population dynamics in the natural world is not associated with egg-production saturation. Instead, it is related to the nonlinearity and self-regulatory inhibition in the synergistic effect of tick cooperation and crowding within groups. We propose the sub-linear Gamma-Ricker function as an appropriate nonlinearity. Furthermore, we highlight the significance of diapaused development in causing multiple time lags in structured tick population dynamics models and introduce sharp conditions for persistence and global convergence behaviors in such models.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2023)
Article
Mathematics, Applied
Chuangxia Huang, Xiaodan Ding
Summary: This paper addresses the dynamic behaviors of a diffusive Nicholson's blowflies equation with two distinct distributed delays, i.e., diapause and developmental delays. Two novel criteria are established to ensure global exponential stability and characterize long time dynamic behavior. The obtained theoretical results encompass some existing ones. Two explanatory examples are performed to substantiate the analytical findings.
APPLIED MATHEMATICS LETTERS
(2023)
Article
Mathematics, Interdisciplinary Applications
Bo Li, Tian Huang
Summary: This paper proposes an approximate optimal strategy based on a piecewise parameterization and optimization (PPAO) method for solving optimization problems in stochastic control systems. The method obtains a piecewise parameter control by solving first-order differential equations, which simplifies the control form and ensures a small model error.
CHAOS SOLITONS & FRACTALS
(2024)
Article
Mathematics, Interdisciplinary Applications
Guram Mikaberidze, Sayantan Nag Chowdhury, Alan Hastings, Raissa M. D'Souza
Summary: This study explores the collective behavior of interacting entities, focusing on the co-evolution of diverse mobile agents in a heterogeneous environment network. Increasing agent density, introducing heterogeneity, and designing the network structure intelligently can promote agent cohesion.
CHAOS SOLITONS & FRACTALS
(2024)
Article
Mathematics, Interdisciplinary Applications
Gengxiang Wang, Yang Liu, Caishan Liu
Summary: This investigation studies the impact behavior of a contact body in a fluidic environment. A dissipated coefficient is introduced to describe the energy dissipation caused by hydrodynamic forces. A new fluid damping factor is derived to depict the coupling between liquid and solid, as well as the coupling between solid and solid. A new coefficient of restitution (CoR) is proposed to determine the actual physical impact. A new contact force model with a fluid damping factor tailored for immersed collision events is proposed.
CHAOS SOLITONS & FRACTALS
(2024)
