This paper describes a new variant of the averaging of the Navier–Stokes equations for axisymmetric flow of a viscous incompressible fluid with a minimum number of simplifying hypotheses. The complete system is spatially one-dimensional differential equations describing the dynamics of blood flow in the large arteries.
An inverse spectral problem is studied for arbitrary order differential operators on noncompact graphs. A uniqueness theorem of recovering potentials from the Weyl matrices is proved.
The structure of idempotent matrices in partial semigroups of matrices of arbitrary sizes with elements from arbitrary Boolean algebra with conjunctive and disjunctive partial multiplications is investigated. The connection of solvability of the simplest matrix equations with some kind of idempotent matrices which are called “secondary idempotents” is shown. Also we show the connection of arbitrary idempotent matrices with secondary idempotents and investigate their properties.
The article is devoted to the investigation of three-element boundary value problem of Carleman type for bianalytic functions. A constructive method for solution in a circle was found for the case when the problem was not reducible to a two-element boundary value problems without a shift.
In this paper some properties of periodic groups of operators which connected with frames theory are considered. We proof that there are no strongly continuous and uniformly bounded periodic one-parameter group of operators in Banach space which eigenvectors are cross-frame.
In this paper we study equiconvergence expansions in trigonometric Fourier series, and in eigenfunctions and associated functions of an integral operator whose kernel suffers jumps at the sides of the square inscribed in the unit square.
The paper is devoted to investigation of the spectrum of some classes of matrix operators. The relations between the parts of the spectrum of the matrix operators with corresponding parts of its elements are established.
