We introduce and study a conserved version of the Fisher equation. Within a population biology context, this model describes spatially extended populations in which the total number of individuals is fixed due to either biotic or environmental factors. We find a rich spectrum of dynamical phases including a pseudotraveling wave and, in the presence of the Allee effect, a phase transition from a...

In recent years, numerous approaches have been applied for finding the solutions of functional equations. One of them is the optimal homotopy asymptotic method. In current paper, this method has been applied for obtaining the approximate solution of Fisher equation. The reliability of the method will be shown by solving some examples of various kinds and comparing the obtained outcomes with the ...

The Fisher-Stefan model involves solving the Fisher-KPP equation on a domain whose boundary evolves according to Stefan-like condition. alleviates two practical limitations of standard when applied biological invasion. First, unlike equation, solutions have compact support, enabling one define interface between occupied and unoccupied regions unambiguously. Second, admits for which population b...

We study a nonlocal reaction-diffusion-mutation equation modeling the spreading of a cane toads population structured by a phenotypical trait responsible for the spatial diffusion rate. When the trait space is bounded, the cane toads equation admits traveling wave solutions [7]. Here, we prove a Bramson type spreading result: the lag between the position of solutions with localized initial data...

Spreading of bacteria in a highly advective, disordered environment is examined. Predictions of super-diffusive spreading for a simplified reaction-diffusion equation are tested. Concentration profiles display anomalous growth and super-diffusive spreading. A perturbation analysis yields a crossover time between diffusive and super-diffusive behavior. The time’s dependence on the convection vel...

Abstract In this paper, we study the numerical solutions of Fisher’s equation and to a nonlinear diffusion equation of the Fisher type by differential quadrature method. Fisher's equation combines diffusion with logistic nonlinearity. The equation occurs in logistic population growth models, neurophysiology and nuclear reactions. Therefore, numerical study of these types of equations is very im...

Numerical solutions of the generalized Burgers-Fisher equation are presented based on a polynomial-based differential quadrature method with minimal computational effort. To achieve this, a combination of a polynomial-based differential quadrature method in space and a third-order strong stability preserving Runge-Kutta scheme in time have been used. The proposed technique successfully worked t...

in this paper, we consider the variational homotopy perturbation method (vhpm) to obtain an approximate series solution for the generalized fisher’s equation which converges to the exact solution in the region of convergence. comparisons are made among the variational iteration method (vim), the exact solutions and the proposed method. the results reveal that the proposed method is very effectiv...

Structure-preserving numerical schemes for a nonlinear parabolic fourthorder equation, modeling the electron transport in quantum semiconductors, with periodic boundary conditions are analyzed. First, a two-step backward differentiation formula (BDF) semi-discretization in time is investigated. The scheme preserves the nonnegativity of the solution, is entropy stable and dissipates a modified e...

The local fractional variational iteration method is applied to a modified Fisher?s equation defined on Cantor sets with the fractal conditions. solution process simple, and accuracy of approximate high. provides an unrivaled tool for differential equations. Key word: equation, analytical solutions, method, derivative