Browsing by Author "Asamoah, Joshua Kiddy K."

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    A comprehensive cost-effectiveness analysis of control of maize streak virus disease with Holling’s Type II predation form and standard incidence
    (Elsevier, 2022-06) Seidu, Baba; Asamoah, Joshua Kiddy K.; Wiah, Eric Neebo; Ackora-Prah, Joseph; 0000-0002-7066-246X
    Maize streak virus disease, caused by the maize streak virus, has been identified as severe vector-borne disease in Africa. In most regions of the continent, the disease is generally uncontrolled, and in epidemic years, it contributes to massive yield losses and famine. We propose a Holling-type predation functional response to explore the disease transmission. We show the sensitivity indices of various embedded parameters in the basic reproduction number. To illustrate the dynamics of the disease of the maize–leafhopper interaction, we perform a numerical simulation, and the results are graphically displayed. Incorporating four control methods (infection control, predation control, removal of infected maize plants, and insecticide application) into the basic model yields an optimal control issue. We used the Incremental Cost-Effectiveness Ratio technique to evaluate the most cost-effective combination of the four controls. We notice that the most cost-effective strategy combines the simultaneous adoption of the four controls.
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    A fractal–fractional order model for exploring the dynamics of Monkeypox disease
    (Elsevier, 2023-08) Wireko, Fredrick Asenso; Adu, Isaac Kwasi; Sebil, Charles; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    This study explores the biological behaviour of the Monkeypox disease using a fractal–fractional operator. We discuss the existence and uniqueness of the solution of the model using the fixed-point concept. We further show that the Monkeypox fractal–fractional model is stable through the Hyers–Ulam and Hyers–Ulam Rassias stability criteria. The epidemiological threshold of the model is obtained. The numerical simulation for the proposed model is obtained using the Newton polynomial. For instance, the disease dies out at lower fractional values. We investigated the effects of some key parameters on the dynamics of the disease. The variation of the parameters shows that quarantine and isolation are effective approaches to managing, controlling, or eradicating the Monkeypox disease.
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    A fractional order age-specific smoke epidemic model
    (Elsevier, 2023) Addai, Emmanuel; Asamoah, Joshua Kiddy K.; Zhang, Lingling; Essel, John Fiifi; 0000-0002-7066-246X
    This paper presents a nonlinear fractional mathematical model for the smoke epidemic that includes two age groups. To solve the smoke epidemic, the Atangana-Baleanu-Caputo fractional derivative is used. The Banach and Krasnoselskii type fixed point theorem is used to determine existence and uniqueness. We explored model stability using the Hyers-Ulam form of stability. Using Lagrange interpolation, the behaviour of the smoke epidemic of the 2-age group model is generated. The numerical simulation shows that the model has po- tential for both groups, and that age-specific interventions can be used to reduce smoking rates in the general population.
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    A fractional order Ebola transmission model for dogs and humans
    (Elsevier, 2024-05) Adu, Isaac K.; Wireko, Fredrick A.; Osman, Mojeeb Al-R. El-N.; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    Ebola is a serious disease that affects people; in many cases, it results in death. Ebola outbreaks have also occurred in communities where residents keep pets, particularly dogs. Due to a lack of food, the dogs must hunt for food. Dogs eat the internal organs of wildlife that the locals have killed and eaten, as well as small dead animals that are found within the communities which may contain the Ebola virus. This study introduces a mathematical model based on the Caputo–Fabrizio derivative to describe the Ebola transmission dynamics between dogs and humans. The model’s existence and the uniqueness of its solution were investigated using fixedpoint theory. Furthermore, through the Sumudu transform criterion, we established that the Caputo–Fabrizio Ebola model is Picard stable. Some qualitative analysis was also carried out to investigate the Ebola propagation trend in the dog-to-human model. The proposed model is fitted to the reported Ebola incidence in Uganda between October 15, 2022, and November 2, 2022. The Ebola reproduction number obtained using the cumulative data was 2.65. It is noticed that as the fractional order reduces, the Ebola reproduction number also reduces. We derived a numerical scheme for our model using the two-step Lagrange interpolation. It has been discovered that the fractional orders significantly influence the model, indicating that natural occurrences could affect the dynamics of Ebola. It is observed that when the recovery rate is enhanced, such as through the hospitalisation of Ebola-infected individuals, the disease will reduce. Finally, as we ensure a reduction in the contact rate among the dog’s compartments, the disease does not spread adiabatically. Therefore, we urge that quarantine measures be put in place to control interactions among the dogs during the outbreak.
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    A fractionalcontrolmodeltostudyMonkeypox transportnetwork-relatedtransmission
    (World Scientific, 2024-08) Zhang, Nan; Emmanuel, Addai; Mezue, MaryNwaife; Rashid, Saima; Akinnubi, Abiola; Abdul-Hamid, Zalia; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    Effective disease control measures to manage the spread of Monkeypox (Mpox) virus are crucial, especially given the serious public health risks posed by the ongoing global epidemic in regions where the virus is both prevalent and not. This study introduces a precise model, based on the Caputo fractional derivative, which takes into account both human and non-human populations as well as public transportation, to delve into the transmission characteristics of Mpox outbreaks. By employing the fixed-point theorem, we have precisely determined the solutions regarding existence and uniqueness. We have analyzed the stability of various equilibrium states within the model to assess Mpox’s transmission capabilities. Additionally, through detailed numerical simulations, we have gauged the impact of critical model parameters that contribute to enhancing Mpox prevention and management strategies. The insights gained from our research significantly enrich epidemiological understanding and lay the foundation for improved disease containment approaches.
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    A hierarchical intervention scheme based on epidemic severity in a community network
    (Springer, 2023-07) He, Runzi; Luo, Xiaofeng; Asamoah, Joshua Kiddy K.; Zhang, Yongxin; Li, Yihong; Jin, Zhen; Sun, Gui-Quan; 0000-0002-7066-246X
    As there are no targeted medicines or vaccines for newly emerging infectious diseases,isolation among communities (villages, cities, or countries) is one of themost effectiveintervention measures. As such, the number of intercommunity edges (NIE) becomesone of themost important factor in isolating a place since it is closely related to normallife. Unfortunately, how NIE affects epidemic spread is still poorly understood. In this paper, we quantitatively analyzed the impact of NIE on infectious disease transmissionby establishing a four-dimensional SIR edge-based compartmental model with two communities. The basic reproduction number R0( l ) is explicitly obtained subjectto NIE l . Furthermore, according to R0(0) with zero NIE, epidemics spreadcould be classified into two cases. When R0(0) > 1 for the case 2, epidemics occurwith at least one of the reproduction numbers within communities greater than one,and otherwise when R0(0) < 1 for case 1, both reproduction numbers within communitiesare less than one. Remarkably, in case 1, whether epidemics break out stronglydepends on intercommunity edges. Then, the outbreak threshold in regard to NIEis also explicitly obtained, below which epidemics vanish, and otherwise break out.The above two cases form a severity-based hierarchical intervention scheme for epidemics.It is then applied to the SARS outbreak in Singapore, verifying the validityof our scheme. In addition, the final size of the system is gained by demonstrating theexistence of positive equilibrium in a four-dimensional coupled system. Thoretical results are also validated through numerical simulation in networks with the Poisson and Power law distributions, respectively. Our results provide a new insight into controlling epidemics.
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    A Mathematical Analysis of the Impact of Immature Mosquitoes on the Transmission Dynamics of Malaria
    (Wiley, 2024-09) Sualey, Nantogmah Abdulai; Akuka, Philip N. A.; Seidu, Baba; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    This study delves into the often-overlooked impact of immature mosquitoes on the dynamics of malaria transmission. By employing a mathematical model, we explore how these aquatic stages of the vector shape the spread of the disease. Our analytical findings are corroborated through numerical simulations conducted using the Runge–Kutta fourth-order method in MATLAB. Our research highlights a critical factor in malaria epidemiology: the basic reproduction number R0 . We demonstrate that when R0 is below unity R0 < 1 , the disease-free equilibrium exhibits local asymptotic stability. Conversely, when R0 surpasses unity R0 > 1 , the disease-free equilibrium becomes unstable, potentially resulting in sustained malaria transmission. Furthermore, our analysis covers equilibrium points, stability assessments, bifurcation phenomena, and sensitivity analyses. These insights shed light on essential aspects of malaria control strategies, offering valuable guidance for effective intervention measures.
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    A mathematical model of corruption dynamics endowed with fractal–fractional derivative
    (Elsevier, 2023-08) Nwajeri, Ugochukwu Kizito; Asamoah, Joshua Kiddy K.; Ugochukwu, Ndubuisi Rich; Omamea, Andrew; Jin, Zhen; 0000-0002-7066-246X
    Numerous organisations across the globe have significant challenges about corruption, characterised by a systematic, endemic, and pervasive nature that permeates various societal establishments. Hence, we propose the fractional order model of corruption, which encompasses the involvement of corrupt individuals across various stages of education and employment. Specifically, we examine the presence of corruption among children in elementary schools, youths in tertiary institutions, adults in civil services, adults in government and public offices, and individuals who have renounced their involvement in corrupt practices. The basic reproduction number of the system was determined by utilising the next-generation matrix. The strength number was obtained by calculating the second derivative of the corruption-related compartments. The examined model solution’s existence, uniqueness, and stability were established using the Krasnoselski fixed point theorem, the Banach contraction principle, and the Ulam–Hyers theorem, respectively. Based on the numerous figures presented, our simulations indicate a positive correlation between the decline in fractal– fractional order and the increase in the number of individuals susceptible to corruption. This phenomenon results in an increase in the prevalence of corruption among designated sectors of the general population. The persistence of corruption in society is a significant challenge to its eradication, as individuals who see personal gains from engaging in corrupt practices tend to exhibit a recurring inclination towards such behaviour. Nevertheless, it is recommended that to mitigate corruption within various corruption-prone subcategories, there is a need to enhance the level of consciousness and promotion of anti-corruption measures throughout all societal establishments.
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    A nonlinear fractional epidemic model for the Marburg virus transmission with public health education
    (Scientific Reports, 2023) Addai, Emmanuel; Adeniji, Adejimi; Ngungu, Mercy; Tawiah, Godfred Kuffuor; Marinda, Edmore; Asamoah, Joshua Kiddy K.; Khan, Mohammed Altaf; 0000-0002-7066-246X
    In this study, a deterministic model for the dynamics of Marburg virus transmission that incorporates the impact of public health education is being formulated and analyzed. The Caputo fractional-order derivative is used to extend the traditional integer model to a fractional-based model. The model’s positivity and boundedness are also under investigation. We obtain the basic reproduction number R0 and establish the conditions for the local and global asymptotic stability for the disease-free equilibrium of the model. Under the Caputo fractional-order derivative, we establish the existenceuniqueness theory using the Banach contraction mapping principle for the solution of the proposed model. We use functional techniques to demonstrate the proposed model’s stability under the Ulam-Hyers condition. The numerical solutions are being determined through the Predictor- Corrector scheme. Awareness, as a form of education that lowers the risk of danger, is reducing susceptibility and the risk of infection. We employ numerical simulations to showcase the variety of realistic parameter values that support the argument that human awareness, as a form of education, considerably lowers susceptibility and the risk of infection.
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    A Novel Analysis of Generalized Perturbed Zakharov–Kuznetsov Equation of Fractional-Order Arising in Dusty Plasma by Natural Transform Decomposition Method
    (Hindawi, 2022-06) Alhazmi, Sharifah E.; Abdelmohsen, Shaimaa A. M.; Alyami, Maryam Ahmed; Ali, Aatif; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    The natural transform decomposition method (NTDM) is a relatively new transformation method for finding an approximate differential equation solution. In the current study, the NTDM has been used for obtaining an approximate solution of the fractional-order generalized perturbed Zakharov–Kuznetsov (GPZK) equation. The method has been tested for three nonlinear cases of the fractional-order GPZK equation. The absolute errors are analyzed by the proposed method and the q-homotopy analysis transform method (q-HATM). 3D and 2D graphs have shown the proposed method’s accuracy and effectiveness. NTDM gives a much-closed solution after a few terms.
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    A Novel Image Encryption Technique Based on Cyclic Codes over Galois Field
    (Hindawi, 2022-02) Asif, Muhammad; Asamoah, Joshua Kiddy K.; Hazzazi, Mohammad Mazyad; Alharbi, Adel R.; Ashraf, Muhammad Usman; Alghamdi, Ahmed M.; 0000-0002-7066-246X
    In the modern world, the security of the digital image is vital due to the frequent communication of digital products over the open network. Accelerated advancement of digital data exchange, the importance of information security in the transmission of data, and its storage has emerged. Multiple uses of the images in the security agencies and the industries and the security of the confidential image data from unauthorized access are emergent and vital. In this paper, Bose Chaudhary Hocquenghem (BCH) codes over the Galois field are used for image encryption. )e BCH codes over the Galois field construct MDS (maximum distance separable) matrices and secret keys for image encryption techniques. )e encrypted image is calculated, by contrast, correlation, energy, homogeneity, and entropy. Histogram analysis of the encrypted image is also assured in this paper. )e proposed image encryption scheme’s security analysis results are improved compared to the original AES algorithm. Further, security agencies can utilize this work for their confidential image data.
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    A Study on Dynamics of CD4+ T-Cells under the Effect of HIV-1 Infection Based on a Mathematical Fractal-Fractional Model via the Adams-Bashforth Scheme and Newton Polynomials
    (MDPI, 2022-04) Najafi, Hashem; Etemad, Sina; Patanarapeelert, Nichaphat; Asamoah, Joshua Kiddy K.; Rezapour, Shahram; Sitthiwirattham, Thanin; 0000-0002-7066-246X
    In recent decades, AIDS has been one of the main challenges facing the medical community around the world. Due to the large human deaths of this disease, researchers have tried to study the dynamic behaviors of the infectious factor of this disease in the form of mathematical models in addition to clinical trials. In this paper, we study a new mathematical model in which the dynamics of CD4+ T-cells under the effect of HIV-1 infection are investigated in the context of a generalized fractal-fractional structure for the first time. The kernel of these new fractal-fractional operators is of the generalized Mittag-Leffler type. From an analytical point of view, we first derive some results on the existence theory and then the uniqueness criterion. After that, the stability of the given fractal-fractional system is reviewed under four different cases. Next, from a numerical point of view, we obtain two numerical algorithms for approximating the solutions of the system via the Adams-Bashforth method and Newton polynomials method. We simulate our results via these two algorithms and compare both of them. The numerical results reveal some stability and a situation of lacking a visible order in the early days of the disease dynamics when one uses the Newton polynomial.
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    A theoretical and numerical analysis of a fractal–fractional two-strain model of meningitis
    (Elsevier, 2022-06) Rezapour, Shahram; Asamoah, Joshua Kiddy K.; Hussain, Azhar; Ahmad, Hijaz; Banerjee, Ramashis; Etemad, Sina; Botmart, Thongchai; 0000-0002-7066-246X
    Meningitis is an inflammation of the membranes that surround and protect the brain and spinal cord. Typically, the enlargement is caused by a bacterial or viral infection of the fluid around the brain and spinal cord. For many years, licensed vaccinations against meningococcal, pneumococcal, and Haemophilus influenzae diseases have been accessible. Vaccines are meant to protect against the most dangerous strains of these germs, which are known as serotypes or serogroups. There have been significant increases in strain coverage and vaccine availability throughout time, but there is no universal vaccine against these illnesses. In this study, we explore the mathematical features of a new six-compartmental fractal–fractional two-strain model of meningitis. With the use of compact functions and 𝜙 − 𝜓-contractions, we establish the existence of solutions. To study the unique solutions, we employ the Banach principle. On the basis of the Hyers-Ulam definition for the fractal– fractional two-strain model of meningitis, stable solutions are examined. From the numerical simulations, we notice that as the fractal–fractional order decreases, the number of infected individuals with strain 1 of meningitis decreases, while the number of infected individuals with strain 2 rises. This means that all serotypes or serogroups need to be controlled effectively for the disease to be closed up.
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    Comparison of the anisotropic and isotropic macroscopic traffic flow models
    (Engineering and Applied Science Letters, 2023-06) Fosu, Gabriel Obed; Gogovi, Gideon K.; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    Second-order macroscopic vehicular traffic flow models are categorized under two broad headings based on the direction of their characteristics. Faster-than-vehicle waves are often called isotropic models vis-á-vis anisotropic models with slower-than-vehicle characteristic speed. The dispute on the supremacy among these families of models is the motivation for this paper. This paper compares and contrasts six distinctive second-order macroscopic models using a numerical simulation and analysis. Three models are characterized by faster-than-vehicle waves with their corresponding anisotropic counterparts. Simulation results on the formation of deceleration waves and the dissolution of acceleration fans are presented to graphically compare the wave profiles of the selected isotropic and anisotropic traffic models. Observably, these opposing models can all characterize these physical traffic phenomena to the same degree. Thus, faster characteristic speed conceptualization of second-order macroscopic equations does not tantamount to model failure but rather lies in the explanation of this property.
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    Cost–benefit analysis of the COVID-19 vaccination model incorporating different infectivity reductions
    (2024-05) Asamoah, Joshua Kiddy K.; Appiah,, Raymond Fosu; Jin, Zhen; Yang, Junyuan; 0000-0002-7066-246X
    The spread and control of coronavirus disease 2019 (COVID-19) present a worldwide economic and medical burden to public health. It is imperative to probe the effect of vaccination and infectivity reductions in minimizing the impact of COVID-19. Therefore, we analyze a mathematical model incorporating different infectivity reductions. This work provides the most economical and effective control methods for reducing the impact of COVID-19. Using data fromGhana as a sample size, we study the sensitivity of the parameters to estimate the contributions of the transmission routes to the effective reproduction number Re. We also devise optimal interventions with cost–benefit analysis that aim to maximize outcomes while minimizing COVID-19 incidences by deploying cost-effectiveness and optimization techniques. The outcomes of this work contribute to a better understanding of COVID-19 epidemiology and provide insights into implementing interventions needed to minimize the COVID-19 burden in similar settings worldwide.
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    Evaluation of the Efficacy of Wolbachia Intervention on Dengue Burden in a Population: A Mathematical Insight
    (IEEE, 2022-05) Abidemi, Afeez; Fatoyinbo, Hammed Olawale; Asamoah, Joshua Kiddy K.; Muni, Sishu Shankar; 0000-0002-7066-246X
    This paper discusses the development and analysis of a nonlinear mathematical model to describe the transmission dynamics and control of dengue disease within the interacting human and mosquito populations. The model, governed by a twelve-dimensional system of ordinary differential equations, captures the subpopulation of symptomatic infected humans with severe dengue symptoms and Wolbachia-infected mosquito population. The dengue-free equilibrium is globally asymptotically stable with respect to the key dengue threshold, 𝑅0. Numerical simulations assess Wolbachia coverage and the fraction of symptomatic infectious humans that develop severe symptoms. The impact of various Wolbachia coverage levels on disease spread is quantified through efficiency analysis.
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    Examining Dynamics of Emerging Nipah Viral Infection with Direct and Indirect Transmission Patterns: A Simulation-Based Analysis via Fractional and Fractal-Fractional Derivatives
    (Hindawi, 2023-10) Ullah, Saif; Li, Shuo; AlQahtani, Salman A.; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    (contaminated foods-to-human) transmission routes via the Caputo fractional and fractional-fractal modeling approaches. +e model is vigorously analyzed both theoretically and numerically. +e possible equilibrium points of the system and their existence are investigated based on the reproduction number. +e model exhibits three equilibrium points, namely, infection-free, infected 6ying foxes free, and endemic. Furthermore, novel numerical schemes are derived for the models in fractional and fractalfractional cases. Finally, an extensive simulation is conducted to validate the theoretical results and provide an impact of the model on the disease incidence. We believe that this study will help to incorporate such mathematical techniques to examine the complex dynamics and control the spread of such infectious diseases.
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    Fractal-Fractional Caputo Maize Streak Virus Disease Model
    (MDPI, 2023-02) Ackora-Prah, Joseph; Seidu, Baba; Okyere, Eric; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    Maize is one of the most extensively produced cereals in the world. The maize streak virus primarily infects maize but can also infect over 80 other grass species. Leafhoppers are the primary vectors of the maize streak virus. When feeding on plants, susceptible vectors can acquire the virus from infected plants, and infected vectors can transmit the virus to susceptible plants. However, because maize is normally patchy and leafhoppers are mobile, leafhoppers will always be foraging for food. Therefore, we want to look at how leafhoppers interact on maize farms using Holling’s Type III functional response in a Caputo fractal-fractional derivative sense. We show that the proposed model has unique positive solutions within a feasible region. We employed the Newton polynomial scheme to numerically simulate the proposed model to illustrate the qualitative results obtained. We also studied the relationship between the state variables and some epidemiological factors captured as model parameters. We observed that the integer-order versions of the model exaggerate the impact of the disease. We also observe that the increase in the leafhopper infestation on maize fields has a devastating effect on the health of maize plants and the subsequent yield. Furthermore, we noticed that varying the conversion rate of the infected leafhopper leads to a crossover effect in the number of healthy maize after 82 days. We also show the dynamics of varying the maize streak virus transmission rates. It indicates that when preventive measures are taken to reduce the transmission rates, It will reduce the low-yielding effect of maize due to the maize streak virus disease.
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    Fractal-fractional order dynamics and numerical simulations of a Zika epidemic model with insecticide-treated nets
    (2022-06) Addai, Emmanuel; Zhang, Lingling; Ackora-Prah, Joseph; Gordon, Joseph Frank; Asamoah, Joshua Kiddy K.; Essel, John Fiifi; 0000-0002-7066-246X
    Fractional order and fractal order are mathematical tools that can be used to model realworld problems. In order to demonstrate the usefulness of these operators, we develop a new fractal-fractional model for the propagation of the Zika virus. This model includes insecticide-treated nets and the generalized fractal-fractional Mittag-Leffler kernel. The existence, uniqueness, and Ulam–Hyres stability conditions for the given system are determined. Using the Newton polynomial, the numerical scheme is described. From the numerical simulations, we notice that a change in the fractal-fractional order directly affects the dynamics of the Zika virus. We also notice that the use of fractal order only converges to faster than the use of fractional order only. Testing the inherent potency of insecticide-treated nets when the fractal-fractional order is 0.99 indicates that increased use of insecticide-treated nets increases the number of healthy humans. The fractalfractional analysis captures the geometric pattern of the Zika virus that is repeated at every scale, which cannot be captured by classical geometry. This backs up the idea that the best way to control the disease is to know enough about how it spread in the past.
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    Fractal-Fractional SIRS Epidemic Model with Temporary Immunity Using Atangana-Baleanu Derivative
    (Commun. Math. Biol. Neurosci., 2022-05) Okyere, Eric; Seidu, Baba; Nantomah, Kwara; Asamoah, Joshua Kiddy K.; 0000-0002-7066-246X
    The basic SIRS deterministic model is one of the powerful and important compartmental modeling frameworks that serve as the foundation for a variety of epidemiological models and investigations. In this study, a nonlinear Atangana-Baleanu fractal-fractional SIRS epidemiological model is proposed and analysed. The model’s equilibrium points (disease-free and endemic) are studied for local asymptotic stability. The existence of the model’s solution and its uniqueness, as well as the Hyers-Ulam stability analysis, are established. Numerical solutions and phase portraits for the fractal-fractional model are generated using a recently constructed and effective Newton polynomial-based iterative scheme for nonlinear dynamical fractal-fractional model problems. Our numerical simulations demonstrate that fractal-fractional dynamic modeling is a very useful and appropriate mathematical modeling tool for developing and studying epidemiological models.