Güngör, Nihan; Sağır, Birsen

Petranuarat and Kemprasit (Southeast Asian Bull Math 21:139–147, 1997) characterized continuity of the superposition operator acting from the sequence space lp into lq where 1 ≤ p, q < ∞. Sağır and Güngör defined the superposition operator Pg by Pg(x) = (g(k, s, xks))∞k,s=1 for all real double sequences (xks) where g: N2 × R → R and gave continuity of the superposition operator acting from the double sequence spaces Lp into Lq for 1 ≤ p, q < ∞. In this paper, we characterize the continuity of the superposition operator acting from Maddox double sequence spaces L(p) into L(q)where p = (pks) and q = (qks) are bounded double sequences of positive numbers.

Merdan, M.

In this article, an analytical approximate solution of nonlinear fractional convection-diffusion with modified Riemann-Liouville derivative was obtained with the help of fractional variational iteration method (FVIM). A new application of fractional variational iteration method (FVIM) was extended to derive analytical solutions in the form of a series for this equation. It is indicated that the solutions obtained by the FVIM are reliable and an effective method for strongly nonlinear partial equations with modified Riemann-Liouville derivative.

Merdan, M.; Gokdogan, A.; Erturk, V.S.

In this paper, the approximate solution of the differential system modeling HIV infection of CD4+ T cells is obtained by a reliable algorithm based on an adaptation of the standard variational iteration method (VIM), which is called the multi-stage variational iteration method(MSVIM). A comparison between MSVIM and the fourthorder Runge-Kutta method (RK4-method) reveal that the proposed technique is a promising tool to solve the considered problem.