Optimal Procurement of COVID-19 Vaccine with Time-Dependent Holding Cost and Shortages under Cloud Fuzzy Demand Rate

COVID-19 vaccine has emerged as the most powerful weapon against the spread of the coronavirus. Therefore, the management of the vaccine inventory is undoubtedly the most influential and important task for the global distribution of the vaccine. This paper is an attempt to model the vaccine inventory system having time-varying holding costs and partially backlogged shortages. The concept of fuzzy set and cloud pentagonal fuzzy number has been incorporated to make the models more realistic and applicable. Models are solved and validated through numerical examples and graphical representation. Further, sensitivity analysis has been done to identify the most sensitive parameters of all. Finally, managerial insights and conclusions have been drawn to make the vaccine inventory system more robust. © 2023 World Scientific Publishing Company.

IMPACT OF COVID-19 ON FILM INDUSTRY

During the COVID-19 pandemic, almost every sector has paid the price;from which the film industry cannot be excluded. As lockdown and social distancing were imposed during this phase, film industry was also being put on halt. Film industry restored restricted activities in unlock phase. This led to physical working instead of digital. During the shoot, the intensity of spread of COVID-19 among crew members advances through asymptomatic infected individuals. In response to ongoing situation in film industry, a mathematical model is designed. This model suggests that people work in film industry are at the high risk of COVID-19 exposure. Stability analysis along with bifurcation are observed to uphold the findings. © 2022 Watam Press.

Bifurcation Analysis for COVID-19 Model With Inhibitory Effect

Different stages of unlocking have begun for COVID-19 pandemic in some parts of the world. Therefore, it becomes important to focus on inhibitory or psychological effects that help in controlling the spread of COVID-19 pandemic in the society. Considering this, we formulate a SEIQHR mathematical model representing COVID-19 scenario with an incidence function of two infectious classes, namely symptomatic and asymptomatic with the inhibitory effect. The model is said to exhibit two equilibria, namely diseasefree equilibrium (DFE) and endemic equilibrium (EE). Basic reproduction number is computed for the model. The local stability analysis is carried out for both the equilibria using Routh-Hurwitz criterion. The result shows stability of DFE when R0 < 1 and persistence of COVID-19 when R0 > 1. Sensitivity analysis of R0 is also studied to understand the effect of various parameters used in modeling the spread of COVID-19. At the end, numerical results have been studied for the formulated model, showing existence of various bifurcations. The largest Lyapunov exponent is also calculated, indicating complexity of the model with low inhibitory rates. © 2021 River Publishers.

Inventory Model for COVID-19 Medicine under Carbon Emissions Sensitive Demand

In the second wave of COVID-19 pandemic, there is another challenge to face: how to effectively dispense some medicines (like Remdesivir injection) amongst the multitudes to quickly achieve immunity against the corona infection. To overcome this situation, researchers and doctors are continuously active. This result into infected people get recovered. In this context, nations are now getting ready to face one more big challenge that is increases biomedical waste which causes carbon emissions. Since spoilage and deterioration results into a significant loss in medicines which hampers consumer’s satisfaction level as well affect the green environment. Keeping this in mind, the proposed article is addressed for an inventory model with carbon emissions sensitive demand which is a more realistic assumption and carbon tax policy is levied to diminish carbon emissions. A non-linear formulation is revealed with an objective to determine the optimum cycle length as to minimize total cost. The validity of the proposed model is demonstrated by presenting a numerical example. Sensitivity analysis is carried out to verify its factual practice. © 2021, International Forum of Management Scholars. All rights reserved.

Investigation of carbon emissions due to COVID-19 vaccine inventory

Inventory model for vaccine of COVID-19 pandemic is the subject of analysis in the proposed article. The initial registration for vaccination and vaccination of registered individuals is taken during the period under consideration. The paper considers the utility of vaccine during storage, holding cost, purchase cost, manufacturing cost and inspection cost. A fraction of registered individuals who do not turn up for a vaccination is taken into account. All the actions by the player incur carbon emissions. During the whole procedure of vaccination starting from raw material to end user carbon emissions are observed. Carbon emissions in stocking raw material, during inspection, during purchase activity, during set-up and transportation phase and holding it at point of delivery. Maximum carbon emission of 28% occur during purchase activity followed by 21% during transportation at the point of delivery and stocking it at respective places. To follow green policy, carbon tax is levied. A non-linear formulation of the proposed problem is modelled to compute optimum cycle time without allowing shortages. The convexity of the objective function is established through the numerical data. Analysis of carbon emissions and carbon tax levied is carried out through the data. Research Objective: Carbon Emission is one of a cause for ozone layer depletion. Moreover, it causes many ecological disturbances resulting into several environmental temperature variations. These all problem affect an individual’s health. So, there arise a need to frame a mathematical model to decipher relationship between COVID-19 vaccine inventory and effect of carbon emissions. © 2021, The Society for Reliability Engineering, Quality and Operations Management (SREQOM), India and The Division of Operation and Maintenance, Lulea University of Technology, Sweden.

Bio-waste Management During COVID-19

Ever since the transmission of novel coronavirus through human-to-human hit the world. As this disease is spreading every day, hospitalisation of individuals increased. Consequence of this, there is a sudden surge of millions of gloves, masks, hand sanitizers and the other essential equipment in each month. Disposal of these commodities is a big challenge for hospitals and COVID-centre, as they may became the reason of creating pollution and infect the surroundings. Increasing hospitalisation cases of COVID-19 results in raising bio-waste which creates pollution. Observing the scenario, a mathematical model with four compartments is constructed in this article. The threshold value indicates the intensity of pollution that emerged from bio-waste. Stability of the equilibrium point gave the necessary condition. Optimal control theory is outlined to achieve the purpose of this chapter by reducing pollution. Outcomes are analytically proven and also numerically simulated. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Global Stability Analysis Through Graph Theory for Smartphone Usage During COVID-19 Pandemic

During the pandemic due to coronavirus disease-19 (COVID-19), technology is regarded as a boon as well as a curse to human life which has a great impact on surroundings, people and the society. One of the innovative, however, perilous (if misused) inventions of humans is the smartphone which is becoming more and more alarmingly common yet an urgent question to be addressed. A wide application of smartphone technology is observed during this pandemic. It has both positive as well as negative impact on the prominent areas which include education, business, health, social life and furthermore. Moreover, the impact of such an addiction is observed not only among youngsters but has influenced all age groups. This scenario is modelled in this research through non-linear ordinary differential equations, where individuals susceptible to smartphone use will be either positively or negatively infected/addicted, may suffer from health issues procuring medication. Threshold is calculated using the next generation matrix method. Stability analysis is done using graph theory, and for the validation of data, numerical simulation is carried out. This study gives results explaining positive and negative issues on health due to excessive use of smartphone. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Controlling the Transmission of COVID-19 Infection in Indian Districts: A Compartmental Modelling Approach

The widespread of the novel coronavirus (2019-nCoV) has adversely affected the world and is treated as a Public Health Emergency of International Concern by the World Health Organization. Assessment of the basic reproduction number with the help of mathematical modeling can evaluate the dynamics of virus spread and facilitate critical information for effective medical interventions. In India, the disease control strategies and interventions have been applied at the district level by categorizing the districts as per the infected cases. In this study, an attempt has been made to estimate the basic reproduction number R0 based on publically available data at the district level in India. The susceptible-exposed-infected-critically infected-hospitalization-recovered (SEICHR) compartmental model is constructed to understand the COVID-19 transmission among different districts. The model relies on the twelve kinematic parameters fitted on the data for the outbreak in India up to May 15, 2020. The expression of basic reproduction number R0 using the next-generating matrix is derived and estimated. The study also employs three time-dependent control strategies to control and minimize the infection transmission from one district to another. The results suggest an unstable situation of the pandemic that can be minimized with the suggested control strategies. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Effective Lockdown and Plasma Therapy for COVID-19

COVID-19 is a major pandemic threat of 2019–2020 which originated in Wuhan. As of now, no specific anti-viral medication is available. Therefore, many countries in the world are fighting to control the spread by various means. In this chapter, we model COVID-19 scenario by considering compartmental model. The set of dynamical system of nonlinear differential equation is formulated. Basic reproduction number R0 is computed for this dynamical system. Endemic equilibrium point is calculated and local stability for this point is established using Routh-Hurwitz criterion. As COVID-19 has affected more than 180 countries in several ways like medically, economy, etc. It necessitates the effect of control strategies applied by various government worldwide to be analysed. For this, we introduce different types of time dependent controls (which are government rules or social, medical interventions) in-order to control the exposure of COVID-19 and to increase recovery rate of the disease. By using Pontryagins maximum principle, we derive necessary optimal conditions which depicts the importance of these controls applied by the government during this epidemic. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Transmission Dynamics of Covid-19 from Environment with Red Zone, Orange Zone, Green Zone Using Mathematical Modelling

The novel corona virus or Covid-19 spread had its inception in November of 2019, and in March 2020, it was declared as a pandemic. Since its initial stage, it has now already infected over 5 million people, leading to the lockdown of countries around the world, and a halt on global as well as national travel across the globe. Based on this, the research proposes a mathematical Covid-19 model to study the outcome of these classified zones under different control strategies. In the nonlinear mathematical model, the total population has been divided into seven compartments, namely Susceptible, Exposed, Red zone, Orange zone, Green zone, Hospitalized, and Recovered. The spectral radius is calculated to analyze dynamics of the Covid-19. To control the spread of the virus, the parameters of controls are Medical Intervention, Partial Lockdown, and Strict Lockdown. This model has been validated with numerical data. The conclusion validates the implementation of lockdown in curbing Covid-19 cases. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Modelling the Impact of Nationwide BCG Vaccine Recommendations on COVID-19 Transmission, Severity and Mortality

Coronavirus Disease 2019 (COVID-19) is declared as pandemic on 11 March 2020 by World Health Organization (WHO). There are apparent dissimilarities in incidence and mortality of COVID-19 cases in different parts of world. Developing countries in Asia and Africa with fragile health system are showing lower incidence and mortality compared to developed countries with superior health system in Europe and America. Most countries in Asia and Africa have national Bacillus Calmette-Guerin (BCG) vaccination programme, while Europe and America do not have such programme or have ceased it. At present, there is no known Food and Drug Administration (FDA)-approved treatment available for COVID-19 disease. There is no vaccine available currently to prevent COVID-19 disease. As mathematical modelling is ideal for predicting the rate of disease transmission as well as evaluating efficacy of possible public health prevention measures, we have created a mathematical model with seven compartments to understand nationwide BCG vaccine recommendation on COVID-19 transmission, severity and mortality. We have computed two basic reproduction numbers, one at vaccine-free equilibrium point and other at non-vaccine-free equilibrium point, and carried out local stability, sensitivity and numerical analysis. Our result showed that individuals with BCG vaccinations have lower risk of getting COVID-19 infection, shorter hospital stays and increased rate of recovery. Furthermore, countries with long-standing universal BCG vaccination policies have reduced incidence, mortality and severity of COVID-19. Further research will focus on exploring the immediate benefits of vaccination to healthcare workers and patients as well as benefits of BCG re-vaccination. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.