Abstract. In this article, using DiPerna-Lions theory [1], we investigate linear second order stochastic partial differential equations with unbounded and degenerate non-smooth coefficients, and obtain several conditions for existence and uniqueness. Moreover, we also prove the L1integrability and a general maximal principle for generalized solutions of SPDEs. As applications, we study nonlinea...

In the case ω = 1, this space is denoted W (Ω). Sobolev spaces without weights occur as spaces of solutions for elliptic and parabolic partial differential equations. In various applications, we can meet boundary value problems for elliptic equations whose ellipticity is “disturbed” in the sense that some degeneration or singularity appears. This “bad” behaviour can be caused by the coefficient...

In this paper, non-similarity boundary-layer flow of a Newtonian fluid near an asymmetric plane stagnation point with a dimensionless external flow velocity ue = x/(x + 1) is studied. The original boundary-layer equations are transferred into a nonlinear partial differential equation (PDE) with variable coefficients. An analytic technique for strongly nonlinear equations, namely the homotopy an...

Метод остаточных степенных рядов эффективен для получения приближенных аналитических решений дифференциальных уравнений дробного порядка. Вычисление дробной производной коэффициентов степенного ряда, аппроксимирующего точное решение дифференциального уравнения, является недостатком этого метода. Другие известные методы приближенного интегрирования, такие как гомотопическое возмущение, разложени...

In this paper, we study the numerical solution to time-fractional partial differential equations with variable coefficients that involve temporal Caputo derivative. A spectral method based on Gegenbauer polynomials is taken for approximating the solution of the given time-fractional partial differential equation in time and a collocation method in space. The suggested method reduces this type o...

This review paper contains computational methods or solution methodologies for singularly perturbed differential difference equations with negative and/or positive shifts in a spatial variable. survey limits its coverage to singular perturbation arising the modeling of neuronal activity and developed by numerous researchers between 2012 2022. The covered ordinary delay small large shift(s), dif...