Article
Computer Science, Interdisciplinary Applications
J. Waku, K. Oshinubi, J. Demongeot
Summary: This paper aims to study the epidemic state during the COVID-19 pandemic, proposing a continuous estimation of the maximum reproduction number and comparing it with the basic reproduction number. The transmission rate is estimated using the Bernoulli S-I equation by identifying the inflection point of daily new infectious cases. Real data from Cameroon and global outbreak are analyzed, showing significant correlations between socio-economic parameters and epidemiology parameters.
MATHEMATICS AND COMPUTERS IN SIMULATION
(2022)
Article
Materials Science, Multidisciplinary
Oyoon Abdul Razzaq, Daniyal Ur Rehman, Najeeb Alam Khan, Ali Ahmadian, Massimiliano Ferrara
Summary: The whole world is currently fighting against the deadly pandemic COVID'19 with various strategies, such as promoting the use of medical masks, social distancing, and frequent use of sanitizers. By establishing an optimal control dynamical model, the efficacy of each strategy in reducing the virulence of COVID'19 can be evaluated. Among these measures, social distancing and supportive care of infected individuals are found to play significant roles in decreasing the basic reproduction number more rapidly.
RESULTS IN PHYSICS
(2021)
Article
Automation & Control Systems
Marcelo M. Morato, Igor M. L. Pataro, Marcus V. Americano da Costa, Julio E. Normey-Rico
Summary: This study proposes a Nonlinear Model Predictive Control (NMPC) scheme to plan social distancing measures and relaxations in order to mitigate the impact of COVID-19. The proposed scheme is based on an adapted data-driven SIRD model, which adequately represents the contagion curves and is validated with real data and simulation results.
Article
Environmental Sciences
Jiachen Ning, Yuhan Chu, Xixi Liu, Daojun Zhang, Jinting Zhang, Wangjun Li, Hui Zhang
Summary: The COVID-19 pandemic has had significant impacts on global health and economy. Analyzing the early spread patterns can help mitigate losses in future public health emergencies.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Review
Automation & Control Systems
Johannes Koehler, Lukas Schwenkel, Anne Koch, Julian Berberich, Patricia Pauli, Frank Allgoewer
Summary: The study shows that adaptive feedback strategies are required to reliably contain the COVID-19 outbreak, and well-designed policies can significantly reduce the number of fatalities. In dealing with uncertain data and model mismatch, using model predictive control (MPC) to implement a feedback strategy that updates the policy weekly can achieve reliable performance.
ANNUAL REVIEWS IN CONTROL
(2021)
Article
Multidisciplinary Sciences
Liangjian Hu, Meisong Shi, Meili Li, Junling Ma
Summary: In March 2022, the Omicron variant of SARS-CoV-2 spread rapidly in Shanghai, China. Strict non-pharmacological intervention measures, including lockdown and blanket PCR testing, were implemented. However, these measures were not sufficient to reduce the reproduction number to below unity and earlier intervention had limited effect on reducing cases.
Article
Biophysics
Dorothee Lippold, Andreas Kergassner, Christian Burkhardt, Matthias Kergassner, Jonas Loos, Sarah Nistler, Paul Steinmann, Dominik Budday, Silvia Budday
Summary: The COVID-19 pandemic has put the world on edge for over a year. In Germany, local political decisions play a crucial role in controlling the epidemic. A reparameterized SIQRD network model accurately predicts the spread of the pandemic in different counties, providing support for decision makers.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2022)
Article
Medicine, General & Internal
Nancy Vicente-Alcalde, Esther Ruescas-Escolano, Carlos Franco-Paredes, Jose Tuells
Summary: The rapid spread of highly transmissible respiratory infections in carceral settings occurred in a prison in Alicante, Spain during the COVID-19 pandemic. Interventions such as early medical isolation, quarantining of contacts, and regular testing played a crucial role in containing the outbreak.
FRONTIERS IN MEDICINE
(2022)
Article
Engineering, Mechanical
Debashis Saikia, Kalpana Bora, Madhurjya P. Bora
Summary: The study presents a modeling and analysis of the COVID-19 outbreak in India using the SEIR model, accurately predicting the first phase of the pandemic and identifying a critical day representing a sudden shift in transmission patterns. This research provides valuable guidance for future pandemics in developing countries.
NONLINEAR DYNAMICS
(2021)
Article
Infectious Diseases
Philippe Gautret, Philippe Colson, Jean Christophe Lagier, Laurence Camoin-Jau, Audrey Giraud-Gatineau, Sophia Boudjema, Julie Finance, Herve Chaudet, Didier Raoult
Summary: The characteristics of COVID-19 patients in Marseille, France differed between March-April and June-August 2020, with younger and more male patients in the latter period. Patients in June-August were less likely to be hospitalized, transferred to ICU, or die, and had higher viral load compared to those in March-April.
INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES
(2021)
Article
Mathematics
Rana Yousif, Aref Jeribi, Saad Al-Azzawi
Summary: Since the identification of new mutations in the coronavirus, the number of COVID-19 cases worldwide has increased, leading to a new wave of the pandemic. This study used a fractional-order SEIRD model with a Caputo derivative to investigate the spread of COVID-19. The analysis included the characteristics of the system, such as solution boundedness, existence, uniqueness, non-negativity, equilibrium points, and basic reproduction number. The simulation results showed that the current wave of virus spread will continue for the next few months, with an increasing number of infections. The comparison of different fractional-order derivatives indicated that the Caputo derivative better aligned with real data. Moreover, the obtained reproduction number suggested the need for further control measures.
Article
Engineering, Mechanical
Chuanliang Han, Meijia Li, Naem Haihambo, Pius Babuna, Qingfang Liu, Xixi Zhao, Carlo Jaeger, Ying Li, Saini Yang
Summary: Two main mechanisms strongly correlated with the extent of recurrent outbreaks of COVID-19 were identified in the study: sudden increase in cases imported from overseas and relaxation of local government epidemic prevention policies. The compartmental dynamical model demonstrated that imported infected cases and relaxation of government policies have a causal effect on the emergence of a new wave of outbreak, along with variations in the temperature index.
NONLINEAR DYNAMICS
(2021)
Article
Computer Science, Artificial Intelligence
Munish Bhatia, Ankush Manocha, Tariq Ahamed Ahanger, Abdullah Alqahtani
Summary: COVID-19 is a life-threatening contagious virus that has necessitated remote patient surveillance. In this study, a comprehensive framework based on RFID and body-wearable sensors is proposed for the identification and management of COVID-19 patients. By utilizing techniques such as decision trees and temporal network analysis, the framework achieves enhanced classification accuracy and effective tracking of the virus spread.
ARTIFICIAL INTELLIGENCE IN MEDICINE
(2022)
Article
Mathematics, Applied
Azhar Iqbal Kashif Butt, Doremure Badalge Duresha Chamaleen, Muhammad Imran, Saira Batool, Muneerah Al Nuwairan
Summary: In this manuscript, a new COVID-19 epidemic model is designed by incorporating the hospitalization, diagnosed, and isolation compartments into the classic SEIR model. The isolation compartment is further divided into asymptomatic infected and symptomatic infected compartments. The existence of a unique solution and the positivity and boundedness of the solution are proven to validate the proposed model. Equilibrium points and the reproduction number R0 are computed to study disease dynamics. Local and global stabilities at the equilibrium points are also investigated. Sensitivity analysis is conducted to observe the effect of transmission parameters on R0. Two different optimal control problems are designed for optimal control analysis. Pontryagin's maximum principle is used to establish optimality conditions, and computing algorithms are developed for numerical solution. Numerical solutions with discussion are displayed graphically.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Letter
Medicine, General & Internal
N. W. A. N. Y. Wijesekara, Nayomi Herath, K. A. L. C. Kodituwakku, H. D. B. Herath, Samitha Ginige, Thilanga Ruwanpathirana, Manjula Kariyawasam, Sudath Samaraweera, Anuruddha Herath, Senarupa Jayawardena, Deepa Gamge
Summary: In response to a cluster outbreak of COVID-19 among Navy personnel in Sri Lanka, the Ministry of Health initiated an aggressive outbreak management program using the CHIME model to predict case numbers under different social distancing scenarios. Increasing social distancing led to a flattening of the epidemiological curve and a delayed peak. While the actual case numbers initially exceeded projections, they later fell below all predicted trends. Predictive modelling is a useful tool for controlling outbreaks like COVID-19 in closed communities.
MILITARY MEDICAL RESEARCH
(2021)
Article
Engineering, Multidisciplinary
Guoyuan Qi, Jianbing Hu, Ze Wang
APPLIED MATHEMATICAL MODELLING
(2020)
Article
Mathematics, Interdisciplinary Applications
Philippe Faradja, Guoyuan Qi
CHAOS SOLITONS & FRACTALS
(2020)
Article
Mathematics, Interdisciplinary Applications
Hongyan Jia, Wenxin Shi, Lei Wang, Guoyuan Qi
CHAOS SOLITONS & FRACTALS
(2020)
Article
Mathematics, Interdisciplinary Applications
Haiyun Bi, Guoyuan Qi, Jianbing Hu, Philippe Faradja, Guanrong Chen
CHAOS SOLITONS & FRACTALS
(2020)
Article
Engineering, Mechanical
Jianzhe Huang, Guoyuan Qi
NONLINEAR DYNAMICS
(2020)
Article
Mathematics, Applied
Guoyuan Qi, Ting Gou, Jianbing Hu, Guanrong Chen
Summary: In this paper, a four-dimensional conservative system of Euler equations producing periodic orbit has been constructed and studied. By analyzing the Hamiltonian and Casimir functions, three invariants of the conservative system have been found, proving complete integrability as the mechanism for generating periodic orbits. The study reveals hidden dynamics in the transition from periodic orbit to conservative chaos.
Article
Physics, Multidisciplinary
Ze Wang, Guoyuan Qi
Summary: This paper constructs a three-terminal memristor and embeds it into a newly proposed four-dimensional Euler equation, which leads to the establishment of a novel conservative chaotic system. A non-Hamiltonian conservative chaotic system is proposed, where the Hamiltonian of the conservative part determines the chaos generation in the system. Analysis of the dynamic behavior of the system suggests that mechanism adjustment can be used to achieve chaos in the system.
Article
Mathematics, Interdisciplinary Applications
Jianbing Hu, Guoyuan Qi, Ze Wang, Guanrong Chen
Summary: A general formalism describing a type of energy-conservative system is established and analyzed for possible dynamic behaviors from the perspective of geometric invariance. The specific 4D chaotic energy-conservative system constructed shows energy-conservative attractors with chaotic 2-torus and quasiperiodic behaviors. The hidden nature of chaotic attractors and the impact of system parameters on dynamic behaviors are further discussed.
INTERNATIONAL JOURNAL OF BIFURCATION AND CHAOS
(2021)
Article
Automation & Control Systems
Xitong Guo, Guoyuan Qi, Xia Li, Shengli Ma
Summary: The small-scale UAV helicopter has a complex structure and can be stabilized in chaotic oscillations using different controllers, with the HODFC showing the best control performance.
INTERNATIONAL JOURNAL OF CONTROL
(2022)
Article
Engineering, Mechanical
Jianbing Hu, Guoyuan Qi, Xinchen Yu, Lin Xu
Summary: Researchers have developed a compartmental model to assess the controllability of the spread of COVID-19, finding that the effective reproduction number at the inflection point is equal to one. They have also parameterized the effectiveness of quarantine and treatment in different stages to increase modeling accuracy. Adequate vaccinations can lead to an early appearance of the inflection point and significantly reduce subsequent increases in newly confirmed cases.
NONLINEAR DYNAMICS
(2021)
Article
Engineering, Mechanical
Xi Li, Guoyuan Qi, Limin Zhang
Summary: This paper proposes a formation technique for UAVs based on Voronoi graph theory, which transforms all constraints of each UAV in the formation into constraints of the leader UAV. By changing the virtual rigid body structure or shape, it effectively adapts to different constraints, and ultimately proposes an efficient trajectory optimization method.
NONLINEAR DYNAMICS
(2021)
Article
Automation & Control Systems
Xia Li, Guoyuan Qi, Xitong Guo, Zengqiang Chen, Xu Zhao
Summary: This article presents an improved extended state observer (IESO) for estimating the unknown model and disturbance of a quadrotor unmanned aerial vehicle (QUAY), and designs an improved high-order differential feedback controller (IHODFC) to counteract the undesired force. Experimental results demonstrate the superiority of this control scheme.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Automation & Control Systems
Guoyuan Qi, Xia Li, Zengqiang Chen
Summary: This paper introduces the application of the extended state observer (ESO) and the linear compensation function observer (CFO) in estimating unknown models for nonlinear systems. The CFO outperforms the ESO in terms of accuracy and convergence, making a significant improvement in observation quality.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2022)
Article
Automation & Control Systems
Guoyuan Qi, Jiahao Deng, Xia Li, Xinchen Yu
Summary: This study considers the dynamical equations of a quadrotor UAV with uncertainties and disturbances during flight. A model-compensated control idea is proposed for attitude and position tracking, and a controller is designed based on a compensation function observer. Simulation results and experimental validation demonstrate the superiority of this approach in terms of tracking performance, transient performance, interference ability, load variation resistance, and unknown information estimation.
CONTROL ENGINEERING PRACTICE
(2023)