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The coffee berry borer, Hypothenemus hampei, is one of the plagues with the highest incidence and affectation in the coffee plantation. Colombia is a region that promotes the growth and infestation of this plague. The infestation is due to several factors such as Colombia’s climate, geographic location and continuous coffee production. Coffee production is one of the most important agricultural activities in the country. Therefore, it is important to carry out studies concerning the dynamics of the coffee borer. For this reason, this article adapts the behavior of the coffee borer with an epidemiological model type SIR proposed by Kermack y Mckendrick. This model and the final size relation (proposed by Castillo Chavez) will be used to estimate the coefficient that represents the infestation of the plague in terms of the other parameters involved in the dynamic. Besides, different numerical simulations were done in Matlab environment by changing the values of the parameters of the dynamic system.

Modeling wave reflection and transmission is important for a diversity of applications in physics and engineering. Examples can be found in acoustics and electromagnetism. Computational wave propagation requires high order accuracy both in space and time to get accurate phase and dissipation properties. In this paper we derive and evaluate a high order accurate method based on Discontinuous Galerkin Spectral Element Method (DGSEM) to compute reflection and transmission of electromagnetic waves traveling in two homogeneous and isotropic media, separated by a thin plane interfaz, with different physical properties of permittivity " and permeability . To discretize in Space we used DGSEM over a two dimensional Transverse Electric Maxwell Equations. We derived a Riemann solver to compute the numerical flux between the interfaces of two elements of the computational mesh and to add boundary conditions. To discretize in time we use a third order low storage Runge-Kutta of Williamson. Results when compared with the analytical solution, showed spectral convergence in space and third order convergence in time.