Ashyralyev, A.; Ashyralyyev, C.

Abstract: In this paper, we study the integral type of the time-nonlocal boundary value problem for a parabolic equation. The well-posedness of these differential and difference problems in Hölder spaces is established. Numerical illustrations in a test case are presented.

Ashyralyev, Allaberen; Ashyralyyev, Charyyar; Cakalli, H.; Kocinac, L.D.R.; Ashyralyev, A.; Harte, R.; Dik, M.; Canak, I.; Kandemir, H.S.; Tez, M.

In this work, we study time-nonlocal boundary value problem for multi-dimensional parabolic partial differential equation. Two difference schemes for approximate solution of non-local boundary value problem are discussed. Theorems on stability of solutions both difference schemes are given without proof. Numerical results for test examples are outlined.

Dedeturk, Mutlu; Cakalli, H.; Kocinac, L.D.R.; Ashyralyev, A.; Harte, R.; Dik, M.; Canak, I.; Kandemir, H.S.; Tez, M.; Gurtug, O.

In this work, inverse problem for an elliptic equation is studied. We gave a numerical solution of inverse elliptic problem by differential transform method in test example.

Ashyralyyev, Charyyar; Gönenç, Ahmet; Ashyralyev, A.; Ashralyyev, C.; Erdogan, A.S.; Lukashov, A.; Sadybekov, M.

In this work, we consider approximation of nonlocal reverse parabolic problem with second kind boundary and integral conditions. Stability and coercive stability estimates for solution of difference scheme are obtained. Some illustrations of numerical results in examples of one and two dimensional reverse parabolic equations are presented.

Ashyralyyev, Charyyar; Akyuz, Gulzipa; Cakalli, H.; Kocinac, L.D.R.; Ashyralyev, A.; Harte, R.; Dik, M.; Canak, I.; Kandemir, H.S.; Tez, M.

In this work, we discuss a third order of accuracy difference scheme for approximate solution of the elliptic overdetermined multi-point problem in the Hilbert space. Functional operator approach is used to study existence and uniqueness of solution of difference problem. Stability, almost coercive stability and coercive stability estimates for solution of difference scheme are established.

Ashyralyyev, Charyyar; Ashyralyev, A.; Kalmenov, T.S.; Ruzhansky, M.V.; Sadybekov, M.A.; Suragan, D.

In the present paper, identification elliptic problem in a Hilbert space with Dirichlet and integral boundary conditions is discussed. Identification problem is reduced to auxiliary nonlocal boundary value problem with nonlocal integral condition. Operator approach is used to prove stability and coercive stability inequalities for solution of source identification elliptic problem in the case of a self-adjoint positive definite operator in a differential equation. As applications, four mixed boundary value problems for strongly elliptic multidimensional partial differential equation are investigated. Theorems on stability of solutions of these boundary value problems are established.

Ashyralyyev, Charyyar; Cakalli, H.; Kocinac, L.D.R.; Ashyralyev, A.; Harte, R.; Dik, M.; Canak, I.; Kandemir, H.S.; Tez, M.; Gurtug, O.

In this study, the first order of accuracy difference scheme for approximate solution of source identification elliptic problem with integral and second kind boundary conditions is considered. Stability and coercive stability estimates for solution of the difference scheme are described. Moreover, test example with computation results is given.

Ashyralyev, Allaberen; Ashyralyyev, Charyyar; Zvyagin, Viktor G.; Ashyralyev, A.; Ashralyyev, C.; Erdogan, A.S.; Lukashov, A.; Sadybekov, M.

We study the well-posedness of the source identification problem for the two dimensional elliptic differential equation with nonlocal boundary conditions. Applying operator approaches, the exact estimates for the solution of this problem in Hölder norms are established.

Ashyralyev, A.; Ashyralyyev, C.; Zvyagin, V.G.

We study the source identification problem for an elliptic differential equation in a Banach space. The exact estimates for the solution of source identification problem in Hölder norms are obtained. In applications, four elliptic source identification problems are investigated. Stability and coercive stability estimates for solution of source identification problems for elliptic equations are obtained.

Ashyralyev, Allaberen; Ashyralyyev, Charyyar; Cakalli, H.; Kocinac, L.D.R.; Harte, R.; Cavalcanti, V.N.D.; Ashyralyev, A.; Sakalli, I.; Canak, I.; Gurtug, O.

Ashyralyyev, Charyyar; Karabey, Suzan; Cakalli, H.; Kocinac, L.D.R.; Harte, R.; Cavalcanti, V.N.D.; Ashyralyev, A.; Sakalli, I.; Canak, I.; Gurtug, O.

In the present paper, Neumann type elliptic overdetermined multipoint boundary value problem is discussed. The first and second order of accuracy difference schemes (ADSs) for the numerical solution of elliptic overdetermined multipoint boundary value problems are presented. Stability estimates for solutions of difference schemes are obtained. Numerical results for mixed boundary value problem are given.

Ashyralyyev, Charyyar; Çay, Aysel; Ashyralyev, A.; Sadybekov, M.; Lukashov, A.

The current paper is devoted to overdetermined elliptic problem with integral condition for derivatives. This overde-termined problem is converted to auxiliary nonlocal boundary value problem (ANBVP) with integral boundary condition. Well-posedness of abstract problem is established. Then, obtained results are used to obtain stability inequalities for solution of three Neumann-type inverse elliptic problems with integral condition to multidimensional differential equation.

Ashyralyyev, Charyyar; Akyüz, Gulzlpa; Ashyralyev, A.; Sadybekov, M.; Lukashov, A.

In this study, a third order of accuracy difference scheme for Bitsadze-Samarskii type multi-point elliptic overdetermined problem is studied. For solution of constructed difference problem stability, almost coercive stability and coercive stability estimates are established. The theoretical statements for the solution of this difference problem are supported by numerical results in test example by using Matlab.

Ashyralyyev, Charyyar; Öztürk, Beyza; Ashyralyev, A.; Sadybekov, M.; Lukashov, A.

In this study, we generalize the well-known finite difference method to compute derivatives of a real-valued function to approximate complex derivatives wz and wz for complex-valued function w. Exploring different combinations of terms, we derive several approximations to compute the first order derivatives of complex-valued function. The first, second, third and fourth order of accuracy finite differences to calculate derivatives are studied. Error analysis in test examples are carried out by using Matlab program.

Ashyralyyev, Charyyar; Dedeturk, Mutlu; Lukashov, A.; Ashyralyev, A.

Approximation of Dirichlet type overdetermined multidimensional elliptic problem with Dirichlet-Neumann boundary conditions are discussed. A third order of accuracy difference scheme for its approximate solution is proposed. The stability, almost coercive stability and coercive stability inequalities for the solution of constructed difference scheme are established. Test example for a two-dimensional elliptic problem is presented.

Ashyralyev, Allaberen; Cakir, Zafer; Lukashov, A.; Ashyralyev, A.

In this work, we investigate initial-boundary value problems for fractional parabolic equations with the Neumann boundary condition. Stability estimates for the solution of this problem are established. Difference schemes for approximate solution of initial-boundary value problem are constructed. Furthermore, we give theorem on coercive stability estimates for the solution of the difference schemes.

Ashyralyyev, Charyyar; Akyüz, Gulzipa; Lukashov, A.; Ashyralyev, A.

In this study, we discuss well-posedness of Bitsadze-Samarskii type inverse elliptic problem with Dirichlet conditions. We establish abstract results on stability and coercive stability estimates for the solution of this inverse problem. Then, the abstract results are applied to three overdetermined problems for the multi-dimensional elliptic equation with different boundary conditions. Stability inequalities for solutions of these applications are obtained.

Ashyralyyev, Charyyar; Lukashov, A.; Ashyralyev, A.; Malkowsky, E.; Basar, F.

In the present paper, inverse elliptic problem with Neumann type overdetermination is discussed. A fourth order of accuracy difference scheme for the solution of this identification problem is presented. Stability, almost coercive stability and coercive inequalities for the solution of difference problem are obtained. In application, a fourth order approximation of the inverse problem for multidimensional elliptic equation with Neumann type overdetermination and Dirichlet boundary condition is studied.