scholarly journals An SVEIRE Model of Tuberculosis to Assess the Effect of an Imperfect Vaccine and Other Exogenous Factors

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 327 ◽  
Author(s):  
Fatima Sulayman ◽  
Farah Aini Abdullah ◽  
Mohd Hafiz Mohd
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Disease Burden ◽  
Backward Bifurcation ◽  
Effective Control ◽  
General Effect ◽  
Tuberculosis Transmission ◽  
Proposed Model ◽  
Exogenous Factors ◽  
The Impact

This study extends a deterministic mathematical model for the dynamics of tuberculosis transmission to examine the impact of an imperfect vaccine and other exogenous factors, such as re-infection among treated individuals and exogenous re-infection. The qualitative behaviors of the model are investigated, covering many distinct aspects of the transmission of the disease. The proposed model is observed to show a backward bifurcation, even when Rv<1. As such, we assume that diminishing Rv to less than unity is not effective for the elimination of tuberculosis. Furthermore, the results reveal that an imperfect tuberculosis vaccine is always effective at reducing the spread of infectious diseases within the population, though the general effect increases with the increase in effectiveness and coverage. In particular, it is shown that a limited portion of people being vaccinated at steady-state and vaccine efficacy assume a equivalent role in decreasing disease burden. From the numerical simulation, it is shown that using an imperfect vaccine lead to effective control of tuberculosis in a population, provided that the efficacy of the vaccine and its coverage are reasonably high.

scholarly journals KGPMH: A hybrid approach for solving a novel facility location problem

2021 ◽  
Author(s):  
Maryam DehghanChenary ◽  
Arman Ferdowsi ◽  
Fariborz Jolai ◽  
Reza Tavakkoli-Moghaddam
Keyword(s):  
Mathematical Model ◽  
Location Problem ◽  
Hybrid Approach ◽  
Facility Location Problem ◽  
Evaluation Function ◽  
Genetic Approach ◽  
Hub Location ◽  
Hub Location Problem ◽  
Proposed Model ◽  
The Impact

<pre>The focus of this paper is to propose a bi-objective mathematical model for a new extension of a multi-period p-mobile hub location problem and then to devise an algorithm for solving it. The developed model considers the impact of the time spent traveling at the hubs' network, the time spent at hubs for processing the flows, and the delay caused by congestion at hubs with specific capacities. Following the unveiled model, a hybrid meta-heuristic algorithm will be devised that simultaneously takes advantage of a novel evaluation function, a clustering technique, and a genetic approach for solving the proposed model.</pre>

scholarly journals Key Aspects of the Proper Formulation of the Model in Numerical Analysis of the Influence of Mining Exploitation on Buildings

2015 ◽  
Vol 36 (2) ◽  
pp. 17-28
Author(s):  
Lucyna Florkowska ◽  
Jan Walaszczyk
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Numerical Modelling ◽  
Underground Mining ◽  
Structural Characteristics ◽  
Number Of Factors ◽  
Proper Formulation ◽  
Key Aspects ◽  
The Impact ◽  
Complex Matter

Abstract Numerical modelling is an important tool used to analyse various aspects of the impact of underground mining on existing and planned buildings. The interaction between the building and the soil is a complex matter and in many cases a numerical simulation is the only way of making calculations which will take into consideration the co–existence of a number of factors which have a significant influence on the solution. The complexity of the matter also makes it a difficult task to elaborate a proper mathematical model – it requires both a thorough knowledge of geologic conditions of the subsoil and the structural characteristics of the building. This paper discusses the most important problems related to the construction of a mathematical model of a building-mining subsoil system. These problems have been collected on the basis of many years of experience the authors have in observing the surveying and tensometric deformations of the rock–mass and buildings as well as in mathematical and numerical modelling of the observed processes.

Assessing the impact of agrochemicals on schistosomiasis transmission: A mathematical study

2021 ◽  
pp. 2150049
Author(s):  
Liming Cai ◽  
Peixia Yue ◽  
Mini Ghosh ◽  
Xuezhi Li
Keyword(s):  
Mathematical Model ◽  
Sensitivity Analysis ◽  
Numerical Simulations ◽  
Disease Transmission ◽  
Agricultural Pollution ◽  
Parasitic Disease ◽  
Mathematical Study ◽  
Proposed Model ◽  
Existence And Stability ◽  
The Impact

Schistosomiasis is a snail-borne parasitic disease, which is affecting almost 240 million people worldwide. The number of humans affected by schistosomiasis is continuously increasing with the rise in the use of agrochemicals. In this paper, a mathematical model is formulated and analyzed to assess the effect of agrochemicals on the transmission of schistosomiasis. The proposed model incorporates the effects of fertilizers, herbicides and insecticides on susceptible snails and snail predators along with schistosomiasis disease transmission. The existence and stability of the equilibria in the model are discussed. Sensitivity analysis is performed to identify the key parameters of the proposed model, which contributes most in the transmission of this disease. Numerical simulations are also performed to assess the impact of fertilizers, herbicides and insecticides on schistosomiasis outbreaks. Our study reveals that the agricultural pollution can enhance the transmission intensity of schistosomiasis, and in order to prevent the outbreak of schistosomiasis, the use of pesticides should be controlled.

Simulation the sedimentation of a finely dispersed medium under the impact of pressure waves

2012 ◽  
Vol 9 (2) ◽  
pp. 80-85
Author(s):  
C.I. Mikhaylenko ◽  
Yu.R. Valeeva
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Disperse System ◽  
Dispersion Medium ◽  
Solid Particles ◽  
Pressure Waves ◽  
Dispersed Particles ◽  
Coagulation Of Particles ◽  
Dispersed Medium ◽  
The Impact

A mathematical model for a disperse system of gas-solid particles when passing pressure waves is decribed. The following assumptions are made: dispersed particles are capable of coagulation with increasing concentration; the dispersed particles are acted upon by the Stokes forces on the side of the dispersion medium and by gravity. The results of numerical simulation of the processes of sedimentation of a dispersed medium are presented. It is shown that one of the mechanisms of precipitation of fine disperced medium can be coagulation of particles during the passage of pressure waves.

scholarly journals Real and false goals of artificial intelligence

2021 ◽  
pp. 43-48
Author(s):  
Oleg Figovsky ◽  
◽  
Oleg Penskiy ◽  
Keyword(s):  
Artificial Intelligence ◽  
Mathematical Model ◽  
Negative Impact ◽  
Modern Society ◽  
Modern World ◽  
Human Psychology ◽  
Proposed Model ◽  
Numerical Assessment ◽  
Human Thinking ◽  
The Impact

The paper describes and justifies the possible dangers of artificial intelligence to human psychology. The manifestations of this danger in the modern world are illustrated by examples. Authors formulated and proved the hypothesis that under the influence of artificial intelligence on a person some changes in the ways of human thinking are possible. A mathematical model for calculating the influence of artificial intelligence on the psychological parameters of a person is proposed. In order to control the influence of artificial intelligence on society authors suggested to formulate specific goals for the integration of artificial intelligence into society, taking into account the negative impact of this intelligence on human psychology. Based on the formulated goals, a simple mathematical model is offered. This model allows for a quick numerical assessment of the impact society on the "psychology" of the robot and vice versa. Simple example of calculating this influence in modern society demonstrates the work of the proposed model.

scholarly journals On Mathematical Modelling of the Indian Human Hair Industry in the Post-COVID-19 Era

2021 ◽  
Vol 8 (3) ◽  
pp. 447-452
Author(s):  
Shibam Manna ◽  
Tanmay Chowdhury ◽  
Asoke Kumar Dhar ◽  
Juan Jose Nieto
Keyword(s):  
Mathematical Model ◽  
Mathematical Modelling ◽  
Human Hair ◽  
Control Parameter ◽  
Employment Opportunities ◽  
Alternative Employment ◽  
Job Opportunities ◽  
Proposed Model ◽  
The Stability ◽  
The Impact

An attempt to model the human hair industry in the post-COVID-19 pandemic situation using mathematical modelling has been the goal of this article. Here we introduce a novel mathematical modelling using a system of ordinary differential equations to model the human hair industry as well as the human hair waste management and related job opportunities. The growth of human hair in the months of nationwide total lockdown has been taken into account and graphs have been plotted to analyze the effect of Lockdown in this model. The alternative employment opportunities that can be created for collecting excessive hair in the post-pandemic period has been discussed. A probable useful mathematical model and mechanism to utilize the migrant labours who became jobless due to the pandemic situation and the corresponding inevitable lockdown situation resulting out of that crisis has been discussed in this paper. We discussed the stability analysis of the proposed model and obtained the criteria for an optimal profit of the said model. Graphs have also been plotted to analyze the impact of the control parameter on the optimal profit.

scholarly journals CORRELATION-REGRESSION ANALYSIS OF THE COMPETITIVENESS OF ENTERPRISE PRODUCTS

2020 ◽  
Vol 10 (86) ◽  
Author(s):  
Volodymyr Ulanchuk ◽  
◽  
Olena Zharun ◽  
Serhiy Sokolyuk ◽  
◽  
...  
Keyword(s):  
Mathematical Model ◽  
Regression Analysis ◽  
Correlation Equation ◽  
Regression Equation ◽  
Short Term ◽  
Flexible Tool ◽  
Proposed Model ◽  
Using Data ◽  
Short Term Forecasting ◽  
The Impact

The economic purpose of correlation-regression analysis is to determine the possible options for product competitiveness management, as well as an assessment of possible ways to achieve the desired result. The developed model can be used to improve planning and increase the level of product competitiveness. The forecast of results, though for the short term, gives the chance to learn about the prospects of obtaining the appropriate level of competitiveness of products in accordance with the degree of application of the impact on it. The forecast is dynamic and adapts to changes based on the latest data. The proposed model can be integrated into the existing decision support system to increase the competitiveness of products. In addition, correlation-regression analysis makes it possible to estimate the current situation using a regression equation. The mathematical reflection of the study of product competitiveness is the economic-mathematical model, which determines its functioning and assessment of changes in its effectiveness in the event of possible changes in the characteristics of economic activity. The parameters of economic models are estimated using the methods of mathematical statistics according to real statistical information. The task of correlation-regression analysis is to construct and analysis of the economic-mathematical model of the regression equation (correlation equation, which reflects the dependence of the resultant feature on several factor features and gives an estimate of the degree of connection density. Using data on the magnitude and direction of action of the analyzed factors, you can get the data that can be obtained to assess the relevant impact on the current level of product competitiveness. That is, such an analysis is a powerful and flexible tool for studying the relationships between product competitiveness indicators. The use of this method makes it possible to better understanding of the level of influence of factors on the competitiveness of products, and, accordingly, learn to manage the processes that take place, as well as more accurately predict their further interaction. These studies are important for the formation and implementation of management decisions to increase the competitiveness of products, because it narrows the choice of indicators with the greatest impact on its level. The ability to determine short-term forecasting of such impacts makes it possible to determine regional perspectives under the conditions of implemented measures.

scholarly journals Improving Bus Operations through Integrated Dynamic Holding Control and Schedule Optimization

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Shuozhi Liu ◽  
Xia Luo ◽  
Peter J. Jin
Keyword(s):  
Numerical Simulation ◽  
Travel Time ◽  
Optimal Choice ◽  
Fleet Size ◽  
Slack Time ◽  
Proposed Model ◽  
Average Travel Time ◽  
Bus Bunching ◽  
Bus Services ◽  
The Impact

Bus bunching can lead to unreliable bus services if not controlled properly. Passengers will suffer from the uncertainty of travel time and the excessive waiting time. Existing dynamic holding strategies to address bus bunching have two major limitations. First, existing models often rely on large slack time to ensure the validity of the underlying model. Such large slack time can significantly reduce the bus operation efficiency by increasing the overall route travel times. Second, the existing holding strategies rarely consider the impact on the schedule planning. Undesirable results such as bus overloading issues arise when the bus fleet size is limited. This paper explores analytically the relationship between the slack time and the effect of holding control. The optimal slack time determined based on the derived relationship is found to be ten times smaller than in previous models based on numerical simulation results. An optimization model is developed with passenger-orient objective function in terms of travel cost and constraints such as fleet size limit, layover time at terminals, and other schedule planning factors. The optimal choice of control stops, control parameters, and slack time can be achieved by solving the optimization. The proposed model is validated with a case study established based on field data collected from Chengdu, China. The numerical simulation uses the field passenger demand, bus average travel time, travel time variance of road segments, and signal timings. Results show that the proposed model significantly reduce passengers average travel time compared with existing methods.

scholarly journals Predicting the evolution and control of the COVID-19 pandemic in Portugal

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 283 ◽  
Author(s):  
Ricardo J. Pais ◽  
Nuno Taveira
Keyword(s):  
Mathematical Model ◽  
Exponential Growth ◽  
Hospital Care ◽  
Effective Control ◽  
Social Distancing ◽  
And Control ◽  
The Impact

Coronavirus disease 2019 (COVID-19) is a worldwide pandemic that has been affecting Portugal since 2 March 2020. The Portuguese government has been making efforts to contradict the exponential growth through lockdown, social distancing and the usage of masks. However, these measures have been implemented without controlling the compliance degree and how much is necessary to achieve an effective control. To address this issue, we developed a mathematical model to estimate the strength of Government-Imposed Measures (GIM) and predict the impact of the degree of compliance on the number of infected cases and peak of infection. We estimate the peak to be around 650 thousand infected cases with 53 thousand requiring hospital care by the beginning of May if no measures were taken. The model shows that the population compliance of the GIM was gradual between   30% to 75%, contributing to a significant reduction on the infection peak and mortality. Importantly, our simulations show that the infection burden could have been further reduced if the population followed the GIM immediately after their release on 18 March.

Numerical Simulation of the Coffee-ring Effect Inside Containers with Time-dependent Evaporation Rate

2021 ◽  
Author(s):  
Hyundong Kim ◽  
Junxiang Yang ◽  
Sangkwon Kim ◽  
Chaeyoung Lee ◽  
Sungha Yoon ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Numerical Experiments ◽  
Evaporation Rate ◽  
Gravitational Force ◽  
Time Dependent ◽  
Coffee Ring ◽  
Proposed Model ◽  
Coffee Ring Effect ◽  
Ring Effect

Abstract In this work, using a mathematical model and numerical simulation, we investigate the effect of time-dependent evaporation rates on stripe formation inside containers, which is driven by the coffee-ring effect. The coffee particles inside a container move according to random walk and under the gravitational force. Because of the non-uniform evaporation rate, we can observe stripe formation inside a container filled with liquid carrying coffee particles. We perform various numerical experiments to demonstrate the proposed model can simulate the stripe formation in a container.

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