scholarly journals Suppression of COVID-19 infection by isolation time control based on the SIR model and an analogy from nuclear fusion research

2020 ◽  
Author(s):  
Osamu Mitarai ◽  
Nagato Yanagi
Keyword(s):  
Control Parameter ◽  
Reproduction Number ◽  
Nuclear Fusion ◽  
Sir Model ◽  
Vaccination Rate ◽  
High Population Density ◽  
Control Effect ◽  
Particle Loss ◽  
Time Control ◽  
Loss Term

AbstractThe coronavirus disease 2019 (COVID-19) has been damaging our daily life after declaration of pandemic. Therefore, we have started studying on the characteristics of Susceptible-Infectious-Recovered (SIR) model to know about the truth of infectious disease and our future.After detailed studies on the characteristics of the SIR model for the various parameter dependencies with respect to such as the outing restriction (lockdown) ratio and vaccination rate, we have finally noticed that the second term (isolation term) in the differential equation of the number of the infected is quite similar to the “helium ash particle loss term” in deuterium-tritium (D-T) nuclear fusion. Based on this analogy, we have found that isolation of the infected is not actively controlled in the SIR model. Then we introduce the isolation time control parameter q and have studied its effect on this pandemic. Required isolation time to terminate the COVID-19 can be estimated by this proposed method.To show this isolation control effect, we choose Tokyo for the model calculation because of high population density. We determine the reproduction number and the isolation ratio in the initial uncontrolled phase, and then the future number of the infected is estimated under various conditions. If the confirmed case can be isolated in 3∼8 days by widely performed testing, this pandemic could be suppressed without awaiting vaccination. If the mild outing restriction and vaccination are taken together, the isolation control time can be longer. We consider this isolation time control might be the only solution to overcome the pandemic when vaccine is not available.

scholarly journals Fractional SIR-Model for Estimating Transmission Dynamics of COVID-19 in India

J ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 86-100
Author(s):  
Nita H. Shah ◽  
Ankush H. Suthar ◽  
Ekta N. Jayswal ◽  
Ankit Sikarwar
Keyword(s):  
Basic Reproduction Number ◽  
Reproduction Number ◽  
Transmission Rate ◽  
Sir Model ◽  
Time Dependent ◽  
Contact Rate ◽  
Distribution Maps ◽  
Fundamental Parameters ◽  
Different Order ◽  
The Basic Reproduction Number

In this article, a time-dependent susceptible-infected-recovered (SIR) model is constructed to investigate the transmission rate of COVID-19 in various regions of India. The model included the fundamental parameters on which the transmission rate of the infection is dependent, like the population density, contact rate, recovery rate, and intensity of the infection in the respective region. Looking at the great diversity in different geographic locations in India, we determined to calculate the basic reproduction number for all Indian districts based on the COVID-19 data till 7 July 2020. By preparing district-wise spatial distribution maps with the help of ArcGIS 10.2, the model was employed to show the effect of complete lockdown on the transmission rate of the COVID-19 infection in Indian districts. Moreover, with the model's transformation to the fractional ordered dynamical system, we found that the nature of the proposed SIR model is different for the different order of the systems. The sensitivity analysis of the basic reproduction number is done graphically which forecasts the change in the transmission rate of COVID-19 infection with change in different parameters. In the numerical simulation section, oscillations and variations in the model compartments are shown for two different situations, with and without lockdown.

scholarly journals Impact of early detection and vaccination strategy in COVID-19 eradication program in Jakarta, Indonesia

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Dipo Aldila ◽  
Brenda M. Samiadji ◽  
Gracia M. Simorangkir ◽  
Sarbaz H. A. Khosnaw ◽  
Muhammad Shahzad
Keyword(s):  
Mathematical Model ◽  
Basic Reproduction Number ◽  
Reproduction Number ◽  
Vaccination Strategy ◽  
Vaccination Rate ◽  
Rapid Testing ◽  
Social Distancing ◽  
Rapid Spread ◽  
Vaccine Potential ◽  
The Basic Reproduction Number

Abstract Objective Several essential factors have played a crucial role in the spreading mechanism of COVID-19 (Coronavirus disease 2019) in the human population. These factors include undetected cases, asymptomatic cases, and several non-pharmaceutical interventions. Because of the rapid spread of COVID-19 worldwide, understanding the significance of these factors is crucial in determining whether COVID-19 will be eradicated or persist in the population. Hence, in this study, we establish a new mathematical model to predict the spread of COVID-19 considering mentioned factors. Results Infection detection and vaccination have the potential to eradicate COVID-19 from Jakarta. From the sensitivity analysis, we find that rapid testing is crucial in reducing the basic reproduction number when COVID-19 is endemic in the population rather than contact trace. Furthermore, our results indicate that a vaccination strategy has the potential to relax social distancing rules, while maintaining the basic reproduction number at the minimum possible, and also eradicate COVID-19 from the population with a higher vaccination rate. In conclusion, our model proposed a mathematical model that can be used by Jakarta’s government to relax social distancing policy by relying on future COVID-19 vaccine potential.

Estimation of the number of affected people due to the Covid-19 pandemic using susceptible, infected and recover model

2020 ◽  
Vol 31 (08) ◽  
pp. 2050111
Author(s):  
Md. Enamul Hoque
Keyword(s):  
Simple Model ◽  
Basic Reproduction Number ◽  
Numerical Solutions ◽  
Reproduction Number ◽  
Sir Model

The Susceptible, Infected and Recover (SIR) model is a very simple model to estimate the dynamics of an epidemic. In the current pandemic due to Covid-19, the SIR model has been used to estimate the dynamics of infection for various infected countries. Numerical solutions are used to obtain the value of parameters for the SIR model. The maximum and minimum basic reproduction number (14.5 and 2.3) are predicted to be in Turkey and China, respectively.

Optimization of the real-time control strategy in petroleum-refining catalyst production wastewater treatment with shortcut nitrification

RSC Advances ◽  
2015 ◽  
Vol 5 (105) ◽  
pp. 86490-86496 ◽  
Author(s):  
Tianqi Ma ◽  
Shaohui Guo ◽  
Zhihui Guo ◽  
Qiushi Zhu ◽  
Jinfu Chen
Keyword(s):  
Wastewater Treatment ◽  
Real Time ◽  
Control Strategy ◽  
Control Parameter ◽  
Petroleum Refining ◽  
Real Time Control ◽  
High Ph ◽  
The Real ◽  
Time Control ◽  
Catalyst Production

Indicated high pH benefits the accuracy of real-time control strategy, explained why DO as a control parameter is unreliable.

Evolution of SARS-CoV-2 in the state of Alagoas-Brazil via an adaptive SIR model

2020 ◽  
pp. 2150040
Author(s):  
I. F. F. Dos Santos ◽  
G. M. A. Almeida ◽  
F. A. B. F. De Moura
Keyword(s):  
Basic Reproduction Number ◽  
Reproduction Number ◽  
Sir Model ◽  
The State ◽  
Epidemic Dynamics ◽  
Historical Series ◽  
Input Parameters ◽  
Number Formula ◽  
Near Future ◽  
The Basic Reproduction Number

We investigate the spreading of SARS-CoV-2 in the state of Alagoas, northeast of Brazil, via an adaptive susceptible-infected-removed (SIR) model featuring dynamic recuperation and propagation rates. Input parameters are defined based on data made available by Alagoas Secretary of Health from April 19, 2020 on. We provide with the evolution of the basic reproduction number [Formula: see text] and reproduce the historical series of the number of confirmed cases with less than [Formula: see text] error. We offer predictions, from November 16 forward, over the epidemic situation in the near future and show that it will keep decelerating. Furthermore, the same model can be used to study the epidemic dynamics in other countries with great easiness and accuracy.

Mathematical analysis of a tuberculosis model with imperfect vaccine

2019 ◽  
Vol 12 (07) ◽  
pp. 1950073 ◽  
Author(s):  
A. O. Egonmwan ◽  
D. Okuonghae
Keyword(s):  
Reproduction Number ◽  
Transmission Rate ◽  
Disease Incidence ◽  
Vaccination Rate ◽  
Endemic Equilibrium ◽  
Transmission Dynamics ◽  
Treatment Rate ◽  
Globally Asymptotically Stable ◽  
Fast Disease Progression ◽  
Latently Infected

Since 1921, the Bacille Calmette–Guerin (BCG) vaccine continues to be the most widely used vaccine for the prevention of Tuberculosis (TB). However, the immunity induced by BCG wanes out after some time making the vaccinated individual susceptible to TB infection. In this work, we formulate a mathematical model that incorporates the vaccination of newly born children and older susceptible individuals in the transmission dynamics of TB in a population, with a vaccine that can confer protection on older susceptible individuals. In the absence of disease-induced deaths, the model is shown to undergo the phenomenon of backward bifurcation where a stable disease-free equilibrium (DFE) co-exists with a stable positive (endemic) equilibrium when the associated reproduction number is less than unity. It is shown that this phenomenon does not exist in the absence of imperfect vaccine, exogenous reinfection, and reinfection of previously treated individuals. It is further shown that a special case of the model has a unique endemic equilibrium point (EEP), which is globally asymptotically stable when the associated reproduction number exceeds unity. Uncertainty and sensitivity analysis are carried out to identify key parameters that have the greatest influence on the transmission dynamics of TB in the population using the total population of latently infected individuals, total number of actively infected individuals, disease incidence, and the effective reproduction number as output responses. The analysis shows that the top five parameters of the model that have the greatest influence on the effective reproduction number of the model are the transmission rate, the fraction of fast disease progression, modification parameter which accounts for reduced likelihood to infection by vaccinated individuals due to imperfect vaccine, rate of progression from latent to active TB, and the treatment rate of actively infected individuals, with other key parameters influencing the outcomes of the other output responses. Numerical simulations suggest that with higher vaccination rate of older susceptible individuals, fewer new born children need to be vaccinated, in order to achieve disease eradication.

scholarly journals Dynamic modelling of strategies for the control of acute haemorrhagic conjunctivitis outbreaks in schools in Changsha, China (2004–2015)

2016 ◽  
Vol 145 (2) ◽  
pp. 368-378 ◽  
Author(s):  
S. L. CHEN ◽  
R. C. LIU ◽  
F. M. CHEN ◽  
X. X. ZHANG ◽  
J. ZHAO ◽  
...  
Keyword(s):  
Attack Rate ◽  
Reproduction Number ◽  
Intervention Strategy ◽  
Dynamic Modelling ◽  
Sir Model ◽  
School Closure ◽  
School Closures ◽  
Intervention Efficacy ◽  
Combined Intervention ◽  
Lower Morbidity

SUMMARYOutbreaks of acute haemorrhagic conjunctivitis (AHC) – a rapidly progressing and highly contagious infection – often occur in schools during summer and autumn. We used dynamic modelling to evaluate the efficacy of interventions to control AHC outbreaks in schools. A susceptible-infected-recovered (SIR) model was built to simulate AHC outbreaks in Chinese schools, with isolation or school closure added into the model. We used outbreak data from the period 2004–2015 in our models to estimate the effective reproduction number and assess the efficacy of interventions. The median effective reproduction number (uncontrolled) of AHC outbreaks was 7·00 (range 1·77–25·87). The median effective reproduction number (controlled) of AHC outbreaks was 0·16 (range 0·00–2·28). Intervention efficacy is affected by the timing of isolation; earlier isolation is associated with a lower morbidity peak and smaller total attack rate (TAR). School closures were not effective; TARs were almost 100% and did not change even when different school closure durations were adopted. Isolation and school closure as a combined intervention strategy was used to simulate outbreak control, but the efficacy was the same as isolation alone. An isolation programme could be an effective primary intervention during AHC outbreaks in schools. However, school closure is not recommended.

Research on Real-Time Performance of the Distributed Control System Based on RTLinux

2014 ◽  
Vol 945-949 ◽  
pp. 1372-1375
Author(s):  
Peng Zhang ◽  
Qin Guo ◽  
Bin Wang
Keyword(s):  
Control System ◽  
Real Time ◽  
Robot Control ◽  
Real Time Control ◽  
Control Effect ◽  
The Real ◽  
Time Performance ◽  
Time Control ◽  
Testing Experiment ◽  
Time Systems

Through the analysis of RTLinux source code and real-time performance of various testing experiment on the RTLinux, and its application in a distributed robot control system using CAN bus, realize the real-time control of robot joints. Write the code of real-time module on RTLinux, analyzing the real-time performance using related kernel time testing function. Under Linux using QT write user interface for robot control, running on the Linux user space. The interface program and the real-time program communicate via RT-FIFO. Specify the location of each robot joint in the interface program, compared with the feedback from the actual joint position trajectory, evaluate the control effect of real-time systems.

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