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In this paper, a non-linear mathematical model is formulated to examine the impact of rhinoceros beetles on coconut plantations through the interactions among healthy coconut trees, infected trees, and the beetle population. The model consists of three coupled non-linear ordinary differential equations (ODEs) with a Holling type II functional response to describe beetle-induced infection. Positivity and boundedness analyses ensure the biological feasibility of the system. The basic reproduction number (R₀) is derived using the next-generation matrix method to determine the threshold for beetle persistence. Local and global stability analyses of the equilibrium points are performed to investigate the long-term behavior of the system. The biological interpretation of equilibrium points explains the conditions for pest eradication and persistence. Optimal control strategies are incorporated to identify effective measures for reducing beetle infestation. The homotopy perturbation method (HPM) is employed to obtain approximate analytical solutions of the non-linear system. Sensitivity analysis identifies the parameters that strongly influence pest dynamics. Numerical simulations validate the analytical findings and show that reducing the contact rate between beetles and healthy trees can effectively control infestation and protect coconut plantations.

In this paper, a non-linear mathematical model is formulated to examine the impact of rhinoceros beetles on coconut plantations through the interactions among healthy coconut trees, infected trees, and the beetle population. The model consists of three coupled non-linear ordinary differential equations (ODEs) with a Holling type II functional response to describe beetle-induced infection. Positivity and boundedness analyses ensure the biological feasibility of the system. The basic reproduction number (R₀) is derived using the next-generation matrix method to determine the threshold for beetle persistence. Local and global stability analyses of the equilibrium points are performed to investigate the long-term behavior of the system. The biological interpretation of equilibrium points explains the conditions for pest eradication and persistence. Optimal control strategies are incorporated to identify effective measures for reducing beetle infestation. The homotopy perturbation method (HPM) is employed to obtain approximate analytical solutions of the non-linear system. Sensitivity analysis identifies the parameters that strongly influence pest dynamics. Numerical simulations validate the analytical findings and show that reducing the contact rate between beetles and healthy trees can effectively control infestation and protect coconut plantations.

Представленная работа посвящена молекулярно-динамическому моделированию процессов термического воздействия на металлический образец, который состоит из атомов никеля. Для решения этой задачи используется континуальная математическая модель, основанная на уравнениях классической механики Ньютона, выбран численный метод, использующий в основе схему Верле, предложен параллельный алго- ритм и осуществлена его реализация в рамках MPIи OpenMP. С помощью разработанной параллельной программы было проведено исследование термодинамического равновесия атомов никеля при условии нагрева образца до желаемой температуры. В численных экспериментах определены оптимальные параметры методики расчета и физические параметры исследуемого процесса. Полученные численные результаты хорошо согласуются с известными теоретическими и экспериментальными данными.

This work is devoted to molecular dynamic modeling of the thermal impact processes on the metal sample consisting of nickel atoms. For the solution of this problem, a continuous mathematical model on the basis of the classical Newton mechanics equations has been used; a numerical method based on the Verlet scheme has been chosen; a parallel algorithm has been offered, and its realization within the MPI and OpenMP technologies has been executed. By means of the developed parallel program, the investigation of thermodynamic equilibrium of nickel atoms’ system under the conditions of heating a sample to desired temperature has been executed. In numerical experiments both optimum parameters of calculation procedure and physical parameters of analyzed process have been defined. The obtained numerical results are well corresponding to known theoretical and experimental data.