This dissertation concerns efficient numerical treatment of the elliptic partial differential equations with high-contrast coefficients. High-contrast means that the ratio between highest and lowest values of the coefficients is very high, or even infinite. A finite-element discretization of such equations yields a linear system with an illconditioned matrix which leads to significant issues in...

Adaptive multilevel finite element methods are developed and analyzed for certain elliptic systems arising in geometric analysis and general relativity. This class of nonlinear elliptic systems of tensor equations on manifolds is first reviewed, and then adaptive multilevel finite element methods for approximating solutions to this class of problems are considered in some detail. Two a posterio...

In this paper we deal with performance analysis of Monte Carlo algorithm for large linear algebra problems. We consider applicability and efficiency of the Markov chain Monte Carlo for large problems, i.e., problems involving matrices with a number of non-zero elements ranging between one million and one billion. We are concentrating on analysis of the almost Optimal Monte Carlo (MAO) algorithm...

E.H. DOHA1,a, A.H. BHRAWY2,3,b, D. BALEANU4,5,6,c, M.A. ABDELKAWY3,d 1Department of Mathematics, Faculty of Science, Cairo University, Giza, Egypt, E-mail: [email protected] 2Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia, E-mail: [email protected] 3Department of Mathematics, Faculty of Science, Beni-Suef University, Beni-Suef 62511, E...

In its most widespread, classical formulation, the Nernst–Planck– Poisson system for ion transport in electrolytes fails to take into account finite ion sizes. As a consequence, it predicts unphysically high ion concentrations near electrode surfaces. Historical and recent approaches to an approriate modification of the model are able to fix this problem. Several appropriate formulations are co...

Thermal treatment of fresh juice is vital to neutralize harmful bacteria that would pose threat to human health. This work is dedicated to simulate the thermal inactivation of Salmonella enteritidis and e coli and its impact on the degradation of four nutrition compounds: β-carotene, β-cryptozanthin, zeinoxanthin, and ascorbic acid that give fresh fruit juice its benefits. The simulation is con...

For simulations of fluid dynamics in astrophysics, physical viscosity and diffusion are typically neglected. However, in this high Reynolds number regime, real fluids become highly turbulent and turbulent processes mediate substantial transport of momentum and heat that is diffusive in nature. In the absence of models for these processes, code-dependent numerical effects dominate how diffusion ...

Because of random nature of many dependent variables in coastal engineering, treatment of effective parameters is generally associated with uncertainty. Numerical models are often used for dynamic analysis of complex structures, including mechanical systems. Furthermore, deterministic models are not sufficient for exact anticipation of structure’s dynamic response, but probabilistic models...

the rank-k numerical range has a close connection to the construction of quantum error correction code for a noisy quantum channel. for noisy quantum channel, a quantum error correcting code of dimension k exists if and only if the associated joint rank-k numerical range is non-empty. in this paper the notion of joint rank-k numerical range is generalized and some statements of [2011, generaliz...