{"title":"Global analyses of a ratio-dependent state feedback control system for infectious disease","authors":"Chenxi Huang, Qianqian Zhang, Sanyi Tang","doi":"10.1016/j.cnsns.2025.109068","DOIUrl":null,"url":null,"abstract":"<div><div>This paper constructs a state feedback control system grounded in the SIS model to study infectious disease prevention and control measures. A proportional threshold is defined: when the proportion of infected individuals is below the threshold, no interventions will be carried out. However, once the proportion exceeds the predefined threshold, measures like vaccination and isolation will be initiated. After clarifying the ODE system properties, the Poincaré map is defined and classified. Its properties like domain, range, and monotonicity are studied to analyze positive periodic solutions (PSs). We find that if the boundary equilibrium is globally stable and there exists no endemic equilibrium, the state feedback control SIS system, i.e., IDE system, does not possess PSs. When the endemic equilibrium is unique and stable, conditions for the existence and stability of the order-1 positive PS are presented, and the higher-order solutions may exist. What is more, if the endemic equilibrium is unique and unstable, and the ODE system generates a stable limit cycle, the conditions for the existence of order-<span><math><mi>k</mi></math></span> PSs for the IDE system are similarly derived. Finally, through numerical simulations, this study demonstrates that when the endemic equilibrium is unique and unstable, the IDE system exhibits complex bifurcation behavior in response to key control parameters, including period-doubling bifurcations, period-halving bifurcations, and chaos.</div></div>","PeriodicalId":50658,"journal":{"name":"Communications in Nonlinear Science and Numerical Simulation","volume":"151 ","pages":"Article 109068"},"PeriodicalIF":3.4000,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Communications in Nonlinear Science and Numerical Simulation","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1007570425004794","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
This paper constructs a state feedback control system grounded in the SIS model to study infectious disease prevention and control measures. A proportional threshold is defined: when the proportion of infected individuals is below the threshold, no interventions will be carried out. However, once the proportion exceeds the predefined threshold, measures like vaccination and isolation will be initiated. After clarifying the ODE system properties, the Poincaré map is defined and classified. Its properties like domain, range, and monotonicity are studied to analyze positive periodic solutions (PSs). We find that if the boundary equilibrium is globally stable and there exists no endemic equilibrium, the state feedback control SIS system, i.e., IDE system, does not possess PSs. When the endemic equilibrium is unique and stable, conditions for the existence and stability of the order-1 positive PS are presented, and the higher-order solutions may exist. What is more, if the endemic equilibrium is unique and unstable, and the ODE system generates a stable limit cycle, the conditions for the existence of order- PSs for the IDE system are similarly derived. Finally, through numerical simulations, this study demonstrates that when the endemic equilibrium is unique and unstable, the IDE system exhibits complex bifurcation behavior in response to key control parameters, including period-doubling bifurcations, period-halving bifurcations, and chaos.
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The journal publishes original research findings on experimental observation, mathematical modeling, theoretical analysis and numerical simulation, for more accurate description, better prediction or novel application, of nonlinear phenomena in science and engineering. It offers a venue for researchers to make rapid exchange of ideas and techniques in nonlinear science and complexity.
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Topics of interest:
Nonlinear differential or delay equations, Lie group analysis and asymptotic methods, Discontinuous systems, Fractals, Fractional calculus and dynamics, Nonlinear effects in quantum mechanics, Nonlinear stochastic processes, Experimental nonlinear science, Time-series and signal analysis, Computational methods and simulations in nonlinear science and engineering, Control of dynamical systems, Synchronization, Lyapunov analysis, High-dimensional chaos and turbulence, Chaos in Hamiltonian systems, Integrable systems and solitons, Collective behavior in many-body systems, Biological physics and networks, Nonlinear mechanical systems, Complex systems and complexity.
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