In this paper, we formulated a dynamical model of COVID-19 to describe the transmission dynamics of the disease. The well possedness of the formulated model equations was proved. Both local and global stability of the disease free equilibrium and endemic equilibrium point of the model equation was established using basic reproduction number. The results show that, if the basic reproduction numb...

In this research, a two-dimensional mathematical model using  turbulence model was developed in a rectangular channel with granular permeable bed. Finite volume method was used for numerical solution of governing equations. The equations considered are discretized using Hybrid difference scheme while applying SIMPLE algorithm to correct velocity components in the continuity equation. In the dev...

Cross-shore sediment transport is one of the effective factors in erosion and sedimentation, and affects dynamics of the beach profile in coastal areas. Furthermore, sandbar migration due to cross-shore sediment transport mostly effects beach nourishment, displacement of pollutions trapped in sediments, and organism and plants’ lives.  In this manuscript, sandbar migration due to cro...

The regularized layered medium equation is proposed as a model of voltage distribution in a medium consisting of alternating thin films of conducting and dielectric materials. This equation is obtained from the layered medium equation by the introduction of a regularizing perturbation that takes account of the resistance at the interface between adjacent conducting and dielectric layers. The re...

Cube Attack is a successful case of Algebraic Attack. Cube Attack consists of two phases, linear equation extraction and solving the extracted equation system. Due to the high complexity of equation extraction phase in finding linear equations, we can extract nonlinear ones that could be approximated to linear equations with high probability. The probabilistic equations could be considered as l...

 An equation-oriented approach was developed for steady state flowsheeting of a commercial methanol plant. The loop consists of fixed bed reactor, flash separator, preheater, coolers, and compressor. For steady sate flowsheeting of the plant mathematical model of reactor and other units are needed. Reactor used in loop is a Lurgi type and its configuration is rather complex. Previously reactor ...

We consider one aspect of the general problem of unicast equation based rate control in the Internet, which we formulate as follows. When a so called “loss-event” occurs, a data source updates its sending rate by setting it to f(p̂n), where p̂n is an estimate of p, the rate of loss-events. Function f (the target loss-throughput function) defines the objective of the control method: we would like ...

The objective of this work is to develop a mathematical model for evaluating the effect of temperature on the rate of microbial growth. The new mathematical model is derived by combination and modification of the Arrhenius equation and the Eyring-Polanyi transition theory. The new model, suitable for both suboptimal and the entire growth temperature ranges, was validated using a collection of 2...

an internal ballistics model has been developed for performance prediction of a solid propellant rocket motor. inthis model a 1-d unsteady euler equation with source terms is considered. the flow is assumed as a non-reacting mixture of perfect gases with space and time varying thermo physical properties. the governing equations in the combustion chamber are solved numerically by using the stege...