Search academic texts

Information × Registration Number 0219U102086, 0119U002620 , R & D reports Title Constructive methods of analysis of boundary problems and recovery of functions popup.stage_title Head Shidlich Andrii , Доктор фізико-математичних наук Registration Date 18-12-2019 Organization The Institute of Mathematics of NASU popup.description2  In the project, we study the relation in various important functional spaces between the smooth properties of functions and the order of their best approximations using trigonometric polynomials, as well as the order of their approximations by linear summation methods of Fourier series (Zygmund, Fejer, Taylor-Abel-Poisson, etc). The special role is given to the proof of direct and inverse approximative theorems and, as a consequence, to obtain (in terms of the corresponding approximations) the structural characteristics of the functional classes. In the framework of this project we obtain a description of the type of Schur criterion for a class of bounded holomorphic functions in terms of their Fourier– Lager coefficients. In the study of boundary value problems for the linear evolutionary Schrödinger equation in Hilbert space, as well as for the system of integro-differential equations with a degenerate kernel in a non-critical case, the conditions for their solution were obtained. Product Description popup.authors Bondar Ivanna A. Pokutnyi Oleksandr O. Savchuk Viktor V. Yanchenko Sergiy Ya. popup.nrat_date 2020-04-02 Close