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1.
Heliyon ; 9(7): e17628, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37539301

RESUMEN

The focus of this paper is the investigation of an Arrhenius-driven chemical reaction in an upstanding micro-channel over an imposed transverse magnetic field with fully developed constant free convection flow. Subject to suitable boundary conditions, the temperature and velocity equations are resolved in non-dimensional form employing the homotopy perturbation method (HPM). the fundamental flow behaviors of temperature, velocity, and volumetric flow are explored as a consequence of regulating characteristics such as fluid-wall interaction parameter, rarefaction parameter, chemical reaction parameters, wall-ambient temperature difference ratio, and Hartman number. The findings are carefully investigated and graphically represented in several mesh grid graphs. It was established that increasing the values of the rarefaction parameters and chemical reaction results in an upsurge in the fluid velocity and volume flow rate, respectively, whereas increasing the Hartman number results in observable flow retardation. Additionally, when the chemical reactant parameter is ignored, the numerical comparison is in excellent agreement with the previously published results.

2.
Healthc Anal (N Y) ; 3: 100179, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37101804

RESUMEN

The recent global Coronavirus disease (COVID-19) threat to the human race requires research on preventing its reemergence without affecting socio-economic factors. This study proposes a fractional-order mathematical model to analyze the impact of high-risk quarantine and vaccination on COVID-19 transmission. The proposed model is used to analyze real-life COVID-19 data to develop and analyze the solutions and their feasibilities. Numerical simulations study the high-risk quarantine and vaccination strategies and show that both strategies effectively reduce the virus prevalence, but their combined application is more effective. We also demonstrate that their effectiveness varies with the volatile rate of change in the system's distribution. The results are analyzed using Caputo fractional order and presented graphically and extensively analyzed to highlight potent ways of curbing the virus.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36694821

RESUMEN

Background: The COVID-19 pandemic has put the world's survival in jeopardy. Although the virus has been contained in certain parts of the world after causing so much grief, the risk of it emerging in the future should not be overlooked because its existence cannot be shown to be completely eradicated. Results: This study investigates the impact of vaccination, therapeutic actions, and compliance rate of individuals to physical limitations in a newly developed SEIQR mathematical model of COVID-19. A qualitative investigation was conducted on the mathematical model, which included validating its positivity, existence, uniqueness, and boundedness. The disease-free and endemic equilibria were found, and the basic reproduction number was derived and utilized to examine the mathematical model's local and global stability. The mathematical model's sensitivity index was calculated equally, and the homotopy perturbation method was utilized to derive the estimated result of each compartment of the model. Numerical simulation carried out using Maple 18 software reveals that the COVID-19 virus's prevalence might be lowered if the actions proposed in this study are applied. Conclusion: It is the collective responsibility of all individuals to fight for the survival of the human race against COVID-19. We urged that all persons, including the government, researchers, and health-care personnel, use the findings of this research to remove the presence of the dangerous COVID-19 virus.

4.
Adv Contin Discret Model ; 2022(1): 34, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35462615

RESUMEN

We investigate the fractional dynamics of a coronavirus mathematical model under a Caputo derivative. The Laplace-Adomian decomposition and Homotopy perturbation techniques are applied to attain the approximate series solutions of the considered system. The existence and uniqueness solution of the system are presented by using the Banach fixed-point theorem. Ulam-Hyers-type stability is investigated for the proposed model. The obtained approximations are compared with numerical simulations of the proposed model as well as associated real data for numerous fractional-orders. The results reveal a good comparison between the numerical simulations versus approximations of the considered model. Further, one can see good agreements are obtained as compared to the classical integer order.

5.
Microvasc Res ; 138: 104191, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34097918

RESUMEN

This article aims to outline the characteristics of the blood flow conveying copper (Cu) and gold (Au) nanoparticles (NPs) through a non-uniform endoscopic annulus with wall slip under the action of electromagnetic force and Hall currents. The flow of blood with the suspension of hybrid nanoparticles in the annulus is induced by the peristaltic pumping. The governing equations are modeled and then simplified with the postulate of lubrication theory. The resulting non-dimensional momentum equation after simplification is solved analytically by employing the He's homotopy perturbation method (HPM) with the computational software Mathematica program (version 11). The influential role of emerging physical parameters on the physiological features related to the blood flow is inferred graphically and physically. The analytical outcomes reveal that Hall parameter has a diminishing behavior on the blood flow while the inverse impact is endured for mounting Hartmann number. Electromagnetic field and Hall currents offer a superlative mode for regulating blood flow at the time of surgery. An increment in the volume fraction of nanoparticles causes a drop in the blood temperature profile. The trapping phenomenon is also explored with the help of contours. An expansion in Hartmann number reduces the size of entrapped bolus and ultimately vanishes when Hartmann number is very large. This prospective model may be applicable in electromagnetic micro-pumps, medical simulation devices, heart-lung machine (HLM), drug carrying and drug transport systems, cancer diagnosis, tumor selective photothermal therapy, etc.


Asunto(s)
Vasos Sanguíneos/fisiología , Cobre/sangre , Campos Electromagnéticos , Endoscopía , Aleaciones de Oro , Nanopartículas del Metal , Modelos Cardiovasculares , Flujo Pulsátil , Simulación por Computador , Análisis Numérico Asistido por Computador , Flujo Sanguíneo Regional , Reproducibilidad de los Resultados , Estrés Mecánico , Temperatura
6.
Microvasc Res ; 137: 104192, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34081994

RESUMEN

The rheological perspective of blood flow with the suspension of metallic or non-metallic nanoparticles through arteries having cardiovascular diseases is getting more attention due to momentous applications in obstructed hemodynamics, nano-hemodynamics, nano-pharmacology, blood purification system, treatment of hemodynamic ailments, etc. Motivated by the novel significance and research in this direction, a mathematical hemodynamics model is developed to mimic the hemodynamic features of blood flow under the concentration of hybrid nanoparticles through an inclined artery with mild stenosis in the existence of dominating electromagnetic field force, Hall currents, heat source, and porous substance. Copper (Cu) and copper oxide (CuO) nanoparticles are submerged into the blood to form hybrid nano-blood suspension (Cu-CuO/blood). The attribute of the medium porosity on the blood flow is featured by Darcy's law. The mathematical equations describing the flow are formulated and simplified under mild stenosis and small Reynolds number assumptions. To determine the analytical solution of the resulting nonlinear momentum equation, the homotopy perturbation method (HPM) is employed. Several figures are graphed to assess the hemodynamical contributions of various intricate physical parameters on blood flow phenomena through the inclined stenosed artery. Significant outcomes from graphical elucidation envisage that the hemodynamic resistance to the blood flow is reduced due to the dispersion of more hybrid nanoparticles in the blood. The hemodynamic resistance (impedance) increases approximately two times by dispersing 0.11% hybrid nanoparticles in the blood flow. The temperature of Cu-CuO/blood is found to be lower in comparison to Cu-blood and pure blood. Intensification of Hall parameter attenuates the wall shear stress at the arterial wall. The trapping phenomena are also outlined via streamline plots which exemplify the blood flow pattern in the stenosed artery under the variation of the emerging parameters. As anticipated, the addition of a large number of hybrid nanoparticles significantly modulates the blood flow pattern in the stenotic region. The novel feature of this model is the impressive impact of Hall currents on hybrid nanoparticle doped blood flow through the stenosed artery. There is another piece of significance is that HPM is the most suitable method to handle the nonlinear momentum equation under the aforementioned flow constraints. Outcomes of this simulation may be valuable for advanced study and research in biomedical engineering, bio-nanofluid mechanics, nano-pharmacodynamics.


Asunto(s)
Arteriopatías Oclusivas/fisiopatología , Arterias/fisiopatología , Cobre/química , Hemodinámica , Nanopartículas del Metal , Modelos Cardiovasculares , Nanotecnología , Animales , Constricción Patológica , Humanos , Porosidad , Flujo Sanguíneo Regional , Estrés Mecánico
7.
Results Phys ; 22: 103873, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33552882

RESUMEN

In the present work, we investigated the transmission dynamics of fractional order SARS-CoV-2 mathematical model with the help of Susceptible S ( t ) , Exposed E ( t ) , Infected I ( t ) , Quarantine Q ( t ) , and Recovered R ( t ) . The aims of this work is to investigate the stability and optimal control of the concerned mathematical model for both local and global stability by third additive compound matrix approach and we also obtained threshold value by the next generation approach. The author's visualized the desired results graphically. We also control each of the population of underlying model with control variables by optimal control strategies with Pontryagin's maximum Principle and obtained the desired numerical results by using the homotopy perturbation method. The proposed model is locally asymptotically unstable, while stable globally asymptotically on endemic equilibrium. We also explored the results graphically in numerical section for better understanding of transmission dynamics.

8.
Heliyon ; 5(12): e03060, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31890973

RESUMEN

In this paper, an approximate analytical solution of the bistable Allen-Cahn equation is given. The Allen-Cahn equation is a mathematical model to study the phase separation process in binary alloys and emerged as a convection-diffusion equation in fluid dynamics or reaction-diffusion equation in material sciences. A phase transition occurs at the interface when one material changes its composition or structure. The homotopy perturbation method and homotopy analysis method are used for finding the approximate solution. These methods don't need the use of any transformation, discretization, unrealistic restriction and assumption. The error estimates are computed by comparing with a numerical method, and a good agreement is observed.

9.
J Integr Neurosci ; 17(3-4): 503-523, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29710731

RESUMEN

In this work, a comparative study of seven well-known mathematical techniques for the coupled Burgers' equations is reported. The techniques involve in this comparison are as follows: Laplace transform Adomian decomposition method, Laplace transform homotopy perturbation method, Variational iteration method, Variational iteration decomposition method, Variational iteration homotopy perturbation method, the optimal homotopy asymptotic method, and OHAM with Daftardar-Jafari polynomial. Here we considered a practical example which consists of coupled Burgers' equations with the kinematic viscosity ε=1. Convergence and stability analysis is a major part of this analysis. After a careful observation, it is found that the variational iteration method has faster convergence than all the remaining methods. Adomian decomposition method and Homotopy perturbation method show weaker stability in comparison with other involved techniques.

10.
Bioprocess Biosyst Eng ; 41(2): 281-294, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29177718

RESUMEN

The theory of glucose-responsive composite membranes for the planar diffusion and reaction process is extended to a microsphere membrane. The theoretical model of glucose oxidation and hydrogen peroxide production in the chitosan-aliginate microsphere has been discussed in this manuscript for the first time. We have successfully reported an analytical derived methodology utilizing homotopy perturbation to perform the numerical simulation. The influence and sensitive analysis of various parameters on the concentrations of gluconic acid and hydrogen peroxide are also discussed. The theoretical results enable to predict and optimize the performance of enzyme kinetics.


Asunto(s)
Enzimas Inmovilizadas/química , Glucosa Oxidasa/química , Glucosa/química , Membranas Artificiales , Microesferas , Modelos Químicos , Alginatos/química , Quitosano/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química
11.
Neural Netw ; 96: 128-136, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28987976

RESUMEN

This paper presents an algorithm for solving the minimum-energy optimal control problem of conductance-based spiking neurons. The basic procedure is (1) to construct a conductance-based spiking neuron oscillator as an affine nonlinear system, (2) to formulate the optimal control problem of the affine nonlinear system as a boundary value problem based on Pontryagin's maximum principle, and (3) to solve the boundary value problem using the homotopy perturbation method. The construction of the minimum-energy optimal control in the framework of the homotopy perturbation technique is novel and valid for a broad class of nonlinear conductance-based neuron models. The applicability of our method in the FitzHugh-Nagumo and Hindmarsh-Rose models is validated by simulations.


Asunto(s)
Potenciales de Acción , Modelos Neurológicos , Neuronas , Potenciales de Acción/fisiología , Algoritmos , Neuronas/fisiología , Dinámicas no Lineales
12.
Math Biosci ; 283: 38-47, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27840282

RESUMEN

In the present study, the analytical study on blood flow containing nanoparticles through porous blood vessels is done in presence of magnetic field using Homotopy Perturbation Method (HPM). Blood is considered as the third grade non- Newtonian fluid containing nanoparticles. Viscosity of nanofluid is determined by Constant, Reynolds' and Vogel's models. Some efforts have been made to show the reliability and performance of the present method compared with the numerical method, Runge-Kutta fourth-order. The results reveal that the HPM can achieve suitable results in predicting the solution of these problems. Moreover, the influence of some physical parameters such as pressure gradient, Brownian motion parameter, thermophoresis parameter, magnetic filed intensity and Grashof number on temperature, velocity and nanoparticles concentration profiles is declared in this research. The results reveal that the increase in the pressure gradient and Thermophoresis parameter as well as decrease in the Brownian motion parameter cause the rise in the velocity profile. Furthermore, either increase in Thermophoresis or decrease in Brownian motion parameters results in enhancement in nanoparticle concentration. The highest value of velocity is observed when the Vogel's Model is used for viscosity.


Asunto(s)
Vasos Sanguíneos , Sangre , Fenómenos Magnéticos , Modelos Teóricos , Nanopartículas , Porosidad
13.
J Membr Biol ; 250(1): 89-101, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27904934

RESUMEN

A mathematical model developed by Abdekhodaie and Wu (J Membr Sci 335:21-31, 2009), which describes a dynamic process involving an enzymatic reaction and diffusion of reactants and product inside glucose-sensitive composite membrane has been discussed. This theoretical model depicts a system of non-linear non-steady state reaction diffusion equations. These equations have been solved using new approach of homotopy perturbation method and analytical solutions pertaining to the concentrations of glucose, oxygen, and gluconic acid are derived. These analytical results are compared with the numerical results, and limiting case results for steady state conditions and a good agreement is observed. The influence of various kinetic parameters involved in the model has been presented graphically. Theoretical evaluation of the kinetic parameters like the maximal reaction velocity (V max) and Michaelis-Menten constants for glucose and oxygen (K g and K ox) is also reported. This predicted model is very much useful for designing the glucose-responsive composite membranes for closed-loop insulin delivery.


Asunto(s)
Gluconatos/química , Glucosa/química , Insulina/administración & dosificación , Modelos Teóricos , Oxígeno/química , Algoritmos , Difusión , Gluconatos/metabolismo , Glucosa/metabolismo , Cinética , Oxígeno/metabolismo , Soluciones
14.
Springerplus ; 5(1): 1859, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27818897

RESUMEN

In this communication, we describe the Homotopy Perturbation Method with Laplace Transform (LT-HPM), which is used to solve the Lane-Emden type differential equations. It's very difficult to solve numerically the Lane-Emden types of the differential equation. Here we implemented this method for two linear homogeneous, two linear nonhomogeneous, and four nonlinear homogeneous Lane-Emden type differential equations and use their appropriate comparisons with exact solutions. In the current study, some examples are better than other existing methods with their nearer results in the form of power series. The Laplace transform used to accelerate the convergence of power series and the results are shown in the tables and graphs which have good agreement with the other existing method in the literature. The results show that LT-HPM is very effective and easy to implement.

15.
Springerplus ; 5(1): 1473, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27652048

RESUMEN

Modified homotopy perturbation method (HPM) was used to solve the hypersingular integral equations (HSIEs) of the first kind on the interval [-1,1] with the assumption that the kernel of the hypersingular integral is constant on the diagonal of the domain. Existence of inverse of hypersingular integral operator leads to the convergence of HPM in certain cases. Modified HPM and its norm convergence are obtained in Hilbert space. Comparisons between modified HPM, standard HPM, Bernstein polynomials approach Mandal and Bhattacharya (Appl Math Comput 190:1707-1716, 2007), Chebyshev expansion method Mahiub et al. (Int J Pure Appl Math 69(3):265-274, 2011) and reproducing kernel Chen and Zhou (Appl Math Lett 24:636-641, 2011) are made by solving five examples. Theoretical and practical examples revealed that the modified HPM dominates the standard HPM and others. Finally, it is found that the modified HPM is exact, if the solution of the problem is a product of weights and polynomial functions. For rational solution the absolute error decreases very fast by increasing the number of collocation points.

16.
Springerplus ; 5(1): 1267, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27540500

RESUMEN

In this paper, we successfully obtained the exact solutions and the approximate analytic solutions of the (2 + 1)-dimensional KP equation based on the Lie symmetry, the extended tanh method and the homotopy perturbation method. In first part, we obtained the symmetries of the (2 + 1)-dimensional KP equation based on the Wu-differential characteristic set algorithm and reduced it. In the second part, we constructed the abundant exact travelling wave solutions by using the extended tanh method. These solutions are expressed by the hyperbolic functions, the trigonometric functions and the rational functions respectively. It should be noted that when the parameters are taken as special values, some solitary wave solutions are derived from the hyperbolic function solutions. Finally, we apply the homotopy perturbation method to obtain the approximate analytic solutions based on four kinds of initial conditions.

17.
Springerplus ; 5: 449, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27119053

RESUMEN

Fuzzy integro-differential equations is one of the important parts of fuzzy analysis theory that holds theoretical as well as applicable values in analytical dynamics and so an appropriate computational algorithm to solve them is in essence. In this article, we use parametric forms of fuzzy numbers and suggest an applicable approach for solving nonlinear fuzzy integro-differential equations using homotopy perturbation method. A clear and detailed description of the proposed method is provided. Our main objective is to illustrate that the construction of appropriate convex homotopy in a proper way leads to highly accurate solutions with less computational work. The efficiency of the approximation technique is expressed via stability and convergence analysis so as to guarantee the efficiency and performance of the methodology. Numerical examples are demonstrated to verify the convergence and it reveals the validity of the presented numerical technique. Numerical results are tabulated and examined by comparing the obtained approximate solutions with the known exact solutions. Graphical representations of the exact and acquired approximate fuzzy solutions clarify the accuracy of the approach.

18.
Springerplus ; 5: 456, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27119060

RESUMEN

Based on a new trial function, an analytical coupled technique (a combination of homotopy perturbation method and variational method) is presented to obtain the approximate frequencies and the corresponding periodic solutions of the free vibration of a conservative oscillator having inertia and static non-linearities. In some of the previous articles, the first and second-order approximations have been determined by the same method of such nonlinear oscillator, but the trial functions have not been satisfied the initial conditions. It seemed to be a big shortcoming of those articles. The new trial function of this paper overcomes aforementioned limitation. The first-order approximation is mainly considered in this paper. The main advantage of this present paper is, the first-order approximation gives better result than other existing second-order harmonic balance methods. The present method is valid for large amplitudes of oscillation. The absolute relative error measures (first-order approximate frequency) in this paper is 0.00 % for large amplitude A = 1000, while the relative error gives two different second-order harmonic balance methods: 10.33 and 3.72 %. Thus the present method is suitable for solving the above-mentioned nonlinear oscillator.

19.
Springerplus ; 5: 387, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27047713

RESUMEN

In this article, we focus on linear and nonlinear fuzzy Volterra integral equations of the second kind and we propose a numerical scheme using homotopy perturbation method (HPM) to obtain fuzzy approximate solutions to them. To facilitate the benefits of this proposal, an algorithmic form of the HPM is also designed to handle the same. In order to illustrate the potentiality of the approach, two test problems are offered and the obtained numerical results are compared with the existing exact solutions and are depicted in terms of plots to reveal its precision and reliability.

20.
Springerplus ; 5: 276, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27006884

RESUMEN

This article proposes the application of Laplace Transform-Homotopy Perturbation Method and some of its modifications in order to find analytical approximate solutions for the linear and nonlinear differential equations which arise from some variational problems. As case study we will solve four ordinary differential equations, and we will show that the proposed solutions have good accuracy, even we will obtain an exact solution. In the sequel, we will see that the square residual error for the approximate solutions, belongs to the interval [0.001918936920, 0.06334882582], which confirms the accuracy of the proposed methods, taking into account the complexity and difficulty of variational problems.

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