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1.
Dongbei Daxue Xuebao/Journal of Northeastern University ; 44(4):486-494, 2023.
Article in Chinese | Scopus | ID: covidwho-20245271

ABSTRACT

Based on the SEIR model, two compartments for self-protection and isolation are introduced, and a more general infectious disease transmission model is proposed.Through qualitative analysis of the model, the basic reproduction number of the model is calculated, and the local asymptotic stability of the disease-free equilibrium point and the endemic equilibrium point of the model is analyzed through eigenvalue theory and Routh-Hurwitz criterion.The numerical simulation and fitting results of COVID-19 virus show that the proposed SEIQRP model can effectively describe the dynamic transmission process of the infectious disease.In the model, the three parameters, i.e.protection rate, incubation period isolation rate, and infected person isolation rate play a very critical role in the spread of the disease.Raising people's awareness of self-protection, focusing on screening for patients in the incubation period, and isolating and treating infected people can effectively reduce the spread of infectious diseases. © 2023 Northeastern University.All rights reserved.

2.
Kongzhi yu Juece/Control and Decision ; 38(3):699-705, 2023.
Article in Chinese | Scopus | ID: covidwho-20245134

ABSTRACT

To study the spreading trend and risk of COVID-19, according to the characteristics of COVID-19, this paper proposes a new transmission dynamic model named SLIR(susceptible-low-risk-infected-recovered), based on the classic SIR model by considering government control and personal protection measures. The equilibria, stability and bifurcation of the model are analyzed to reveal the propagation mechanism of COVID-19. In order to improve the prediction accuracy of the model, the least square method is employed to estimate the model parameters based on the real data of COVID-19 in the United States. Finally, the model is used to predict and analyze COVID-19 in the United States. The simulation results show that compared with the traditional SIR model, this model can better predict the spreading trend of COVID-19 in the United States, and the actual official data has further verified its effectiveness. The proposed model can effectively simulate the spreading of COVID-19 and help governments choose appropriate prevention and control measures. Copyright ©2023 Control and Decision.

3.
Journal of Managerial Issues ; 35(2):220-239, 2023.
Article in English | ProQuest Central | ID: covidwho-20244152

ABSTRACT

The COVID-19 pandemic has cost the lives of an enormous number of individuals around the world, isolated people, and disrupted businesses. These are the direct and devastating consequences of the disease, however there are other peripheral impacts as well. The pandemic is continuing to threaten the work-life balance (WLB) of employees, disrupting their domestic lives, intensifying their general stress levels, and impacting their ability to focus on their careers. This is a significant problem for both working women as well as men, however this study suggests the negative impact is more disruptive to women. Women represent approximately 46% of the human resources for organizations and they are major contributors to advancements in domains such as healthcare, education, government, and commercial development. Organizations, as a defensive measure, need to adapt policies and procedures in an attempt to moderate the disruptive influences the virus is having on their human resources. This paper explores the extant literature and defragments diverse COVID-19 studies to capture an overall picture of the unique impact the pandemic is having on working women. A qualitative study involving semi-structured in-depth interviews with 20 professional women was conducted. Interviews were reviewed holistically with themes across interviews identified. Resulting themes include WLB expectations post-COVID-19, childcare, employers and expectations, and return to work. Thematic findings are discussed and observations relative to organizational implications are provided. Also offered are thoughts and suggestions for the enhancement of WLB, thereby benefiting both women and their organizations.

4.
Journal of Southeast European & Black Sea Studies ; 23(2):339-363, 2023.
Article in English | Academic Search Complete | ID: covidwho-20243679

ABSTRACT

To counterbalance the deep systemic global crisis triggered by the COVID-19, many countries introduced a vast arsenal of fiscal policy instruments coupled with monetary accommodation. Yet, Turkey's response had almost exclusively relied on credit expansion and loan guarantees while minimizing the role of fiscal policy. Within that context, this article has three interrelated objectives. Firstly, we evaluate the effects of the crisis and the implemented policies on poverty and income distribution. Second, we measure the macroeconomic impacts of COVID-19 on the Turkish economy through a general equilibrium model. We find that these policies had a limited impact on reducing crisis-induced poverty. Finally, we propose alternatives to mitigate the effects of the COVID-19 crisis, which are compatible with fiscal constraints. Our results suggest that by pursuing a targeted fiscal income transfer programme covering wage earners and small-sized enterprises, Turkey could have achieved a more egalitarian and effective response to the Covid-19 crisis. [ FROM AUTHOR] Copyright of Journal of Southeast European & Black Sea Studies is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

5.
IEEE Access ; 11:46956-46965, 2023.
Article in English | Scopus | ID: covidwho-20241597

ABSTRACT

Knowledge payment is a new method of electronic learning that has developed in the era of social media. With the impact of the COVID-19 pandemic, the market for knowledge payment is rapidly expanding. Exploring the factors that influence users' sustained willingness is beneficial for better communication between knowledge payment platforms and users, and for achieving a healthier and more sustainable development of the knowledge payment industry. The model of unsustainable usage behavior of knowledge payment users was constructed on the basis of expectation inconsistency theory, price equilibrium theory, and perceived value theory, using the 'cognitive-emotional-behavioral' model framework of cognitive emotion theory. The data were collected from 348 users through a web-based questionnaire and analyzed using structural equation modeling. Findings show that expectation inconsistency, price equilibrium, and quality value, emotional value, and social value have significant effects on discontinuous use intentions. Discontinuous use intentions also significantly affect discontinuous use behavior. © 2013 IEEE.

6.
Journal of Agricultural & Food Industrial Organization ; 21(1):21-34, 2023.
Article in English | CAB Abstracts | ID: covidwho-20240509

ABSTRACT

This research determines the impacts of COVID-19 US on crawfish production and consumption for 2020 and 2021 using an Equilibrium Displacement Model. In the US, crawfish is one of the seafood commodities where most production is consumed by domestic consumers (7% of domestic consumption is from imports). Crawfish and rice are complementary. Therefore, the impacts of COVID-19 on crawfish consumption simultaneously influence rice production and crawfish producers and consumers. In the first year of COVID-19 (2020), the reduction in crawfish retail demand caused negative effects on final consumers and producers. However, crawfish consumption recovered significantly in the second year (2021), which could compensate for the loss in 2020. Overall, consumer and producer gains ranged from $549 to $626 million if the COVID-19 pandemic only impacted retail consumption. However, in 2021, the increase in production costs due to higher oil/diesel prices and other input prices caused the farm supply to decrease. As a result, total welfare gains ranged from $200 to $228 million. If the demand in 2021 did not increase, but the crawfish farm supply decreased, consumer and producer losses ranged from $929 to $1045 million. Overall, the total effects of COVID-19 on consumers and producers for 2020 and 2021 depend on its effects in 2021. If the demand in 2021 increased following the decrease in farm supply, consumers and producers would benefit from the shocks of COVID-19 due to higher post-COVID-19 demand.

7.
Mathematics ; 11(11):2423, 2023.
Article in English | ProQuest Central | ID: covidwho-20238645

ABSTRACT

As tuberculosis (TB) patients do not have lifetime immunity, environmental transmission is one of the key reasons why TB has not been entirely eradicated. In this study, an SVEIRB model of recurrent TB considering environmental transmission was developed to explore the transmission kinetics of recurrent TB in the setting of environmental transmission, exogenous infection, and prophylaxis. A more thorough explanation of the effect of environmental transmission on recurrent TB can be found in the model's underlying regeneration numbers. The global stability of disease-free and local equilibrium points can be discussed by looking at the relevant characteristic equations. The Lyapunov functions and the LaSalle invariance principle are used to show that the local equilibrium point is globally stable, and TB will persist if the basic reproduction number is larger. Conversely, the disease will disappear if the basic reproduction number is less than one. The impact of environmental transmission on the spread of tuberculosis was further demonstrated by numerical simulations, which also demonstrated that vaccination and reducing the presence of the virus in the environment are both efficient approaches to control the disease's spread.

8.
Advances in Differential Equations and Control Processes ; 28:119-134, 2022.
Article in English | Web of Science | ID: covidwho-20235836

ABSTRACT

Despite ranking amongst the highest in medical systems in Africa and spending a substantial amount on health sector than other African nations, Algeria suffered a major blow in the first wave of the Covid-19 pandemic. Vaccine hesitancy also affected the country adversely in subsequent waves of the disease. This study estimates the number of Covid-19 cases for Algeria in January 2022 using two numerical methods Multi-step Differential Transform Method (MsDTM) and Repeated MsDTM. Stability analysis of the pandemic for the country has also been discussed in the paper.

9.
Fractal and Fractional ; 7(5), 2023.
Article in English | Scopus | ID: covidwho-20234870

ABSTRACT

In this paper, we introduce a SIVR model using the Laplace Adomian decomposition. This model focuses on a new trend in mathematical epidemiology dedicated to studying the characteristics of vaccination of infected communities. We analyze the epidemiological parameters using equilibrium stability and numerical analysis techniques. New mathematical strategies are also applied to establish our epidemic model, which is a pandemic model as well. In addition, we mathematically establish the chance for the next wave of any pandemic disease and show that a consistent vaccination strategy could control it. Our proposal is the first model introducing a vaccination strategy to actively infected cases. We are sure this work will serve as the basis for future research on COVID-19 and pandemic diseases since our study also considers the vaccinated population. © 2023 by the authors.

10.
Lecture Notes in Electrical Engineering ; 954:91-98, 2023.
Article in English | Scopus | ID: covidwho-20234834

ABSTRACT

Beside the unexpected toll of mortality and morbidity caused by COVID-19 worldwide, low- and middle-income countries are more suffering from the devastating issues on economic and social life. This disease has fostered mathematical modelling. In this paper, a SEIAR mathematical model is presented to illustrate how policymakers may apply efficient strategies to end or at least to control the devastating wide spread of COVID-19. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

11.
Revista de Patologia Tropical ; 52(1):11-24, 2023.
Article in English | CAB Abstracts | ID: covidwho-20233213

ABSTRACT

The world is facing a serious viral infection caused by the new Severe Acute Respiratory Syndrome Coronavirus 2. We aimed to evaluate and map the high-risk clusters of COVID-19 in the State of Alagoas, a touristic area in northeastern Brazil, after two years of pandemic by a population-based ecological study, using COVID-19 cases reported in the State of Alagoas, between March, 2020 and April, 2022. We performed a descriptive and statistical analysis of epidemiological data. We then map high-risk areas for COVID-19, using spatial analysis, considering the incidence rate by municipality. 297,972 positive cases were registered;56.9% were female and 42.7% aged between 20 and 39 years old. Men (OR = 1.59) and older than 60 years old (OR = 29.64) had a higher risk of death, while the highest incidence rates of the disease occurred in the metropolitan region. Our data demonstrate the impact of COVID-19 in the State of Alagoas, through the two years of pandemic. Although the number of cases were greater among women and young adults, the chance of death was greater among men and older adults. High-risk clusters of the disease initially occur in metropolitan cities and tourist areas.

12.
Appl Math Model ; 122: 401-416, 2023 Oct.
Article in English | MEDLINE | ID: covidwho-20245397

ABSTRACT

Purpose: The ongoing COVID-19 pandemic imposes serious short-term and long-term health costs on populations. Restrictive government policy measures decrease the risks of infection, but produce similarly serious social, mental health, and economic problems. Citizens have varying preferences about the desirability of restrictive policies, and governments are thus forced to navigate this tension in making pandemic policy. This paper analyses the situation facing government using a game-theoretic epidemiological model. Methodology: We classify individuals into health-centered individuals and freedom-centered individuals to capture the heterogeneous preferences of citizens. We first use the extended Susceptible-Exposed-Asymptomatic-Infectious-Recovered (SEAIR) model (adding individual preferences) and the signaling game model (adding government) to analyze the strategic situation against the backdrop of a realistic model of COVID-19 infection. Findings: We find the following: 1. There exists two pooling equilibria. When health-centered and freedom-centered individuals send anti-epidemic signals, the government will adopt strict restrictive policies under budget surplus or balance. When health-centered and freedom-centered individuals send freedom signals, the government chooses not to implement restrictive policies. 2. When governments choose not to impose restrictions, the extinction of an epidemic depends on whether it has a high infection transmission rate; when the government chooses to implement non-pharmacological interventions (NPIs), whether an epidemic will disappear depends on how strict the government's restrictions are. Originality/value: Based on the existing literature, we add individual preferences and put the government into the game as a player. Our research extends the current form of combining epidemiology and game theory. By using both we get a more realistic understanding of the spread of the virus and combine that with a richer understanding of the strategic social dynamics enabled by game theoretic analysis. Our findings have important implications for public management and government decision-making in the context of COVID-19 and for potential future public health emergencies.

13.
Build Environ ; 241: 110486, 2023 Aug 01.
Article in English | MEDLINE | ID: covidwho-20230628

ABSTRACT

It is now widely recognised that aerosol transport is major vector for transmission of diseases such as COVID-19, and quantification of aerosol transport in the built environment is critical to risk analysis and management. Understanding the effects of door motion and human movement on the dispersion of virus-laden aerosols under pressure-equilibrium conditions is of great significance to the evaluation of infection risks and development of mitigation strategies. This study uses novel numerical simulation techniques to quantify the impact of these motions upon aerosol transport and provides valuable insights into the wake dynamics of swinging doors and human movement. The results show that the wake flow of an opening swinging door delays aerosol escape, while that of a person walking out entrains aerosol out of the room. Aerosol escape caused by door motion mainly happens during the closing sequence which pushes the aerosols out. Parametric studies show that while an increased door swinging speed or human movement speed can enhance air exchange across the doorway, the cumulative aerosol exchange across the doorway is not clearly affected by the speeds.

14.
American Economic Review ; 113(4):939-981, 2023.
Article in English | Web of Science | ID: covidwho-2327496

ABSTRACT

We provide theory and evidence on the relationship between global-ization and pandemics. Business travel facilitates trade and travel leads to human interactions that transmit disease. Trade-motivated travel generates an epidemiological externality across countries. If infections lead to deaths, or reduce individual labor supply, we establish a general equilibrium social distancing effect, whereby increases in relative prices in unhealthy countries reduce travel to those countries. If agents internalize the threat of infection, we show that their behavioral responses lead to a reduction in travel that is larger for higher-trade-cost locations, which initially reduces the ratio of trade to output. (JEL D91, F14, F60, I12, N30, N70, Z31)

15.
International Journal of Health Governance ; 28(2):117-136, 2023.
Article in English | ProQuest Central | ID: covidwho-2324047

ABSTRACT

PurposeThe main motivation of the present study is to understand the severity of the effect of health shock on Iran's oil economy and analyze the role of government under these conditions.Design/methodology/approachDynamic stochastic general equilibrium (DSGE) models can show the precise interactions between market decision-makers in the context of general equilibrium. Since the duration of the virus outbreak and its effect on the economy is not known, it is more appropriate to use these models.FindingsThe results of the survey of hands-on policies scenarios compared to the state of hands-off policy indicate that the effect of government expending shocks on the economy under pandemic disease conditions has much less feedback on macroeconomic variables.Originality/valueAs a proposed policy, it is recommended that the government play a stabilizing role under pandemic disease conditions.Key messages There is no study regarding health shock and its economic effects in Iran using DSGE models. Also, in foreign studies, the health shock in an oil economy has not been modeled.The general idea in the present study is how the prevalence of a pandemic infectious disease affects the dynamics of macroeconomic variables.In three different scenarios, according to the persistence of health disaster risk and the deterioration rate of health capital due to this shock, the model is simulated.In modeling pandemic diseases, quarantine hours are considered as part of the total time of individuals.According to the research findings, it is recommended that the government, as a policy-maker, play a stabilizing role under pandemic crises conditions.

16.
International Journal of Health Governance ; 28(2):100-107, 2023.
Article in English | ProQuest Central | ID: covidwho-2323080
17.
RAIRO: Recherche Opérationnelle ; 57:351-369, 2023.
Article in English | ProQuest Central | ID: covidwho-2320508

ABSTRACT

Information is important market resource. High-quality information is beneficial to increase enterprise's reputation and reduce consumer's verification cost. This paper constructs a two-layer dynamic model, in which enterprises simultaneously conduct price and information game. The goal of profit maximization integrates two types of games into one system. The complex evolution of the two-layer system are studied by equilibrium analysis, stability analysis, bifurcation diagram, entropy and Lyapunov exponent. It is found that improving the information quality through regulations will increase involution and reduce stability of the market. Then, the block chain technology is introduced into the model for improving information quality of the market. It is found that increasing enterprises' willingness to adopt block chain can improve the information quality quickly and effectively, and that is verified by entropy value. Therefore, the application and promotion of new technologies are more effective than exogenous regulations for improving information quality in market.

18.
International Journal of Fuzzy System Applications ; 11(1), 2022.
Article in English | Scopus | ID: covidwho-2319302

ABSTRACT

The COVID-19 pandemic has affected the whole world quite seriously. The number of new infectious cases and death cases are rapidly increasing over time. In this study, a theoretical linguistic fuzzy rule-based susceptible-exposed-infectious-isolated-recovered (SEIIsR) compartmental model has been proposed to predict the dynamics of the transmission of COVID-19 over time considering population immunity and infectiousness heterogeneity based on viral load in the model. The model's equilibrium points have been calculated, and stability analysis of the model's equilibrium points has been conducted. Consequently, the fuzzy basic reproduction number, R0f, of the fuzzy model has been formulated. Finally, the temporal dynamics of different compartmental populations with immunity and infectiousness heterogeneity using the fuzzy Mamdani model are delineated, and some disease control policies have been suggested to get over the infection in no time. Copyright © 2022, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited.

19.
Revista de Análisis Ecónomico ; 38(1):101-135, 2023.
Article in Spanish | ProQuest Central | ID: covidwho-2317821

ABSTRACT

Se ha adaptado un modelo de equilibrio general computado de Argentina para analizar el impacto de la pandemia Covid-19 en la economía y el rol de las políticas anticíclicas para mitigar dicho impacto. Las simulaciones del modelo arrojan resultados consistentes con lo observado en 2020 mostrando un fuerte impacto negativo en el PBI, el desempleo y el bienestar de los hogares. El paquete de políticas anticíclicas logra mitigar en el corto plazo el impacto adverso acerca de algunas variables macroeconómicas y, en particular, respecto del bienestar. Pero a mediano y largo plazo, la menor acumulación de capital y creciente endeudamiento implican menor crecimiento y bienestar. Una política fiscal sostenible -que estabilice la relación deuda-productopermite mediante mayor inversión y empleo que la economía y el bienestar recuperen los niveles del escenario base (recién) al cabo de 10 años.Alternate :A computable general equilibrium model of Argentina was adapted to analyze the impact of the Covid-19 pandemia on the economy and to assess the mitigating effects of anticyclicalpolicies. The simulations are consistent with the observed performance of GDP, unemployment and social welfare. The anticyclical program is effective in reducing the short term adverse impact on several economic and social indicators, particularly, on social welfare. But over the medium and long term, smaller capital accumulation and sovereign indebtment imply lower growth and welfare. A sustainable fiscal policy -that stabilizes the debt-GDP ratio- allows the economy to, through higher investment and employment creation recover the base scenario levels (only) after 10 years.

20.
Revista de Analisis Economico ; 38(1):101-135, 2023.
Article in English, Spanish | Scopus | ID: covidwho-2317820

ABSTRACT

A computable general equilibrium model of Argentina was adapted to analyze the impact of the Covid-19 pandemia on the economy and to assess the mitigating effects of anticyclical policies. The simulations are consistent with the observed performance of GDP, unemployment and social welfare. The anticyclical program is effective in reducing the short term adverse impact on several economic and social indicators, particularly, on social welfare. But over the medium and long term, smaller capital accumulation and sovereign indebtment imply lower growth and welfare. A sustainable fiscal policy –that stabilizes the debt-GDP ratio– allows the economy to, through higher investment and employment creation recover the base scenario levels (only) after 10 years. © 2023, Revista de Analisis Economico. All Rights Reserved.

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