Olumuyiwa J. Peter¹, Amjad S. Shaikh^2,*, Mohammed O. Ibrahim¹, Kottakkaran Sooppy Nisar³, Dumitru Baleanu^4,5,6, Ilyas Khan⁷, Adesoye I. Abioye¹

CMC-Computers, Materials & Continua, Vol.66, No.2, pp. 1823-1848, 2021, DOI:10.32604/cmc.2020.012314

Abstract We propose a mathematical model of the coronavirus disease 2019 (COVID-19) to investigate the transmission and control mechanism of the disease in the community of Nigeria. Using stability theory of differential equations, the qualitative behavior of model is studied. The pandemic indicator represented by basic reproductive number R₀ is obtained from the largest eigenvalue of the next-generation matrix. Local as well as global asymptotic stability conditions for the disease-free and pandemic equilibrium are obtained which determines the conditions to stabilize the exponential spread of the disease. Further, we examined this model by using Atangana–Baleanu fractional derivative operator and existence criteria… More >

S.Y. Wang^1,2, K.M. Lim^2,3, B.C. Khoo^2,3, M.Y. Wang⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.24, No.1, pp. 21-50, 2008, DOI:10.3970/cmes.2008.024.021

Abstract In topology optimization, filtering techniques have become quite popular in practice. In this paper, an accurate and efficient hybrid sensitivity filtering approach based on the traditional and bilateral sensitivity filtering approaches is proposed. In the present hybrid approach, the traditional sensitivity filter is applied to a sub-domain where numerical instabilities are likely to occur to overcome the numerical instabilites robustly. Filtering on mesh-independent holes identified by an image-processing-based technique is prohibited to reduce the computational cost. The bilateral approach is employed for the corresponding nearest neighboring elements of the mesh-independent holes to drive the 0-1 convergence of their boundaries. As… More >