Numerical solutions for the new Coronavirus (COVID 19) mathematical model by the operational matrix using the clique polynomials method.

In this paper, we consider a differential equation system and present a new method based on Clique polynomials (CP-M) to obtain numerical solutions of this system. The system of differential equations is a mathematical model of a new virus called Corona, which causes an infectious disease called COVID-19. By solving this system of equations, we check the transmissibility of the Coronavirus by the CPs method. In particular we turn the system of differential equations into an algebraic system to obtain solutions. Finally, we compare the numerical results obtained by the CPs method with the numerical results of other methods.

Experimental study on classical and metaheuristics algorithms for optimal nano-chitosan concentration selection in surface coating and food packaging.

In this study the Lagrange interpolation optimization algorithm based on two variables with respect to all experimental replicates (POA), was compared with two other heuristics methods (WOA and GOA). Modification of the apple surface by an edible nano coating solution in food packaging was used as case study. The experiment was performed as a factorial test based on completely randomized design by 100 permutations data sets. Results showed a significant difference between the three optimization methods (POA, WOA and GOA) which indicates the necessity of optimization and also efficiency of the present POA. The optimum result by POA, similar to a rose petal property, could rise 72% in surface contact angle (CA). The scanning electron microscopy (SEM) images of the derived surfaces showed almost a uniform spherical nanoparticles morphology. Remarkable advantages of this new approach are no additional material requirement, healthful, easy, inexpensive, fast and affordable technique for surface improvement.