This paper describes a comparison of some numerical methods for solving the advection-diffusion (AD) equation which may be used to describe transport of a pollutant. The one-dimensional advection-diffusion equation is solved by using cubic splines (the natural cubic spline and a ”special” AD cubic spline) to estimate first and second derivatives, and also by solving the same problem using two s...

In this paper, we define the multicubic-quartic and multimixed cubic-quartic mappings characterize them. other words, unify system of functional equations defining a (resp., multicubic-quartic) mapping to single equation, namely, equation. We also show that under what conditions can be multicubic, multiquartic multicubic-quartic. Moreover, by using fixed point theorem, study generalized Hyers-U...

Abstract In this paper, the functional variable method is used to obtain new optical soliton solutions for perturbed stochastic nonlinear Schrödinger equation with generalized anti-cubic nonlinearity and multiplicative white noise. Using some transformations, rational, Jacobi elliptic, Weierstrass, hyperbolic are obtained. Several were proposed, including dark, bright, compacton solutions. Grap...

in cite{p}, park introduced the quadratic $rho$-functional inequalitiesbegin{eqnarray}&& |f(x+y)+f(x-y)-2f(x)-2f(y)| && qquad le  left|rholeft(2 fleft(frac{x+y}{2}right) + 2 fleft(frac{x-y}{2}right)- f(x) -  f(y)right)right|,  nonumberend{eqnarray}where $rho$ is a fixed complex number with $|rho|andbegin{eqnarray}&& left|2 fleft(frac{x+y}{2}right) + 2 fleft(frac{x-y}{2}r...

We use an inverse scattering approach to study multi-peakon solutions of the Degasperis–Procesi (DP) equation, an integrable PDE similar to the Camassa–Holm shallow water equation. The spectral problem associated to the DP equation is equivalent under a change of variables to what we call the cubic string problem, which is a third order non-selfadjoint generalization of the well-known equation ...