SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
The paper determines the crystal structure of a synthetic sodium cadmium metasilicate phase in the Na2O, CdO, SiO2 system, with approximate composition Na2CdSi2O6. X-ray diffraction data, Patterson projections, and three-dimensional Fourier syntheses are used to establish a pseudotetragonal orthorho…
This note studies a general linear boundary value problem for a first order system of composite type in a simply connected planar domain, with one real and one complex unknown and boundary operators involving derivatives up to orders m and n. Under nonvanishing and endpoint compatibility conditions …
The paper studies a one-parameter family of positive approximation operators for continuous functions on the interval [0,1], extending a previously considered case corresponding to alpha equal to 2. It proves uniform convergence and gives estimates of the approximation error in terms of the modulus …
The paper addresses a combinatorial problem concerning arrangements of objects of several prescribed types in a chain such that no two adjacent objects have the same type, motivated by multidimensional order statistics and run distributions. Using a formula for chains with fixed transition numbers b…
This paper proves a central limit theorem for the number of upcrossings of a fixed level by a stationary Gaussian process. The argument studies the variance and higher moments of the crossing count, first showing that under decay of the correlation function the variance diverges, and then that, unde…
This paper gives an explicit classification framework for indecomposable Harish-Chandra modules over the Lie algebra of the proper Lorentz group. Decomposing a module into rotation-subgroup components, the authors express the Lorentz generators through auxiliary operators and derive the relations th…
This note studies complete regularity of stationary random processes through conditions on their spectral densities. For one-dimensional continuous-time processes, it gives sufficient and, in special factored cases, necessary criteria involving entire functions of finite exponential type, continuity…
This note develops a modification of Maslov’s regularizer construction for Cauchy problems involving pseudodifferential, pseudohyperbolic systems. It formulates a canonical operator on Lagrangian manifolds with values in Hilbert space scales associated with an unbounded self-adjoint operator, includ…
The paper addresses the inverse problem of Laval nozzle theory, in which streamlines and gas dynamic parameters are determined from a prescribed velocity distribution on the axis of symmetry. It formulates the problem for irrotational isentropic ideal gas flow in stream function coordinates and prop…
This note studies duality of functors in the category of separated locally convex spaces with morphisms continuous on bicompact sets, using internal Hom and tensor product constructions. It describes the dual functor through conjugate spaces, extremal topologies, and a special topology on values of …
The paper develops a method of lines construction for solutions of the Prandtl boundary-layer equations, principally for axisymmetric three-dimensional nonstationary incompressible flows and for related two-dimensional cases. After transforming variables by using the normalized velocity and introduc…
The paper studies constructive characterizations of nonperiodic function classes in integral metrics by approximation with algebraic polynomials on the interval [-1,1]. It compares the classes defined by ordinary moduli of smoothness and those defined by endpoint-adapted difference conditions, estab…
The paper studies a diffusion equation on a semi-infinite domain with a nonlinear, piecewise boundary condition arising in models of self-oscillations in electrochemical systems with a falling characteristic. It reduces the periodic boundary-value problem to a nonlinear integral equation by represen…
This paper establishes estimates for the Cauchy integral over the boundary of a Lyapunov domain in terms of the analytic capacity, or analytic C-capacity, of the set of singularities of the integrand. It proves bounds for continuous functions analytic off a closed exceptional set and for bounded fun…
The paper studies the stability of a boundary value problem for analytic functions with conjugation on the unit circle, under general assumptions on the coefficient functions. It reduces the problem, via analytic continuation, to a Riemann boundary value problem for two pairs of unknown functions an…
This paper studies local solvability for a class of pseudodifferential equations extending differential operators of constant strength and allowing certain nonconstant-strength operators with characteristics of arbitrary multiplicity. It defines operators with principal and subprincipal homogeneous …
This note studies rational surfaces equipped either with a Galois action over a perfect field or with an action of a finite group, with emphasis on birational invariants and applications to the Cremona group. Using the method of adjunction, it introduces standard models, including surfaces with rati…
This note studies analytic representations of disk type surfaces in Euclidean space with bounded integral mean curvature, using isothermic parametrizations whose generalized Laplacian is a vector valued measure of finite total variation. For polyhedral surfaces, the Laplacian of an isothermic parame…
This note studies the covering, small inductive, and large inductive dimensions of finite products of ordered continua, viewed as bicompact topological spaces. It proves that for a product of n ordered continua, all three dimensions are equal to n. The lower bound is obtained by constructing separat…
This paper examines coastal effects in the vertical component of bay-like geomagnetic variations on Far Eastern island arcs, where sharp conductivity contrasts between seawater and land can produce local anomalies. Using a simplified electromagnetic model for a narrow elongated island near an oceani…
The paper studies a boundary value problem for a generalized Laplace equation in Wiener function space, involving the Lévy Laplacian of a functional and a potential term. For domains defined by a smooth functional with constant positive Lévy Laplacian, it constructs solution functionals using Fourie…
This note applies the contour integral method to a mixed boundary value problem for a parabolic system describing heat and mass transfer in a three-dimensional domain. The argument reduces the problem to an associated spectral problem, constructs a fundamental matrix and Green matrix, and represents…
This paper extends classical ergodic theorems to dynamical systems whose time parameter is a measurable semigroup acting by measure-preserving transformations. It formulates conditions on averaging sets and measures, including Følner-type invariance and size bounds, and proves maximal inequalities t…
This paper gives a statistical derivation of the radiative transfer equation for a scalar wave field in a medium modeled as an ensemble of uncorrelated point isotropic scatterers. Starting from Foldy-type equations for the configuration-averaged field and field correlation, it applies a WKB approxim…
A formula is considered by which the value of the function $f(x)\in C^n$ on a given interval is determined through its values and the values of its derivatives at $m$ points ($m\ge2$) of the given interval. The considered examples demonstrate the possibility of effectively using the obtained general…
This paper describes a class of learning recognition algorithms for separating two disjoint subsets of the vertices of an n-dimensional unit cube, using finite training samples from each set. The method constructs systems of “tubes,” defined by selected essential binary features, centers, and radii,…
This paper considers the problem of free transverse vibrations of a finite visco-elastic rod where one end is fixed and the other is free. Mathematically, the problem is formulated as seeking a solution to the equation: \begin{equation} \frac{\partial^2u}{\partial t^2}+a\frac{\partial^4u}{\partial x…
This note extends previously defined classes of regular functions of several complex variables by introducing classes associated with bounded rotation and contracted distortion, formulated through restrictions to analytic plane sections of a bounded complete bicircular domain. It gives necessary and…
The paper studies the equivalence problem for associative calculi, focusing on how few defining relations are needed to obtain undecidability for equivalence to a fixed word. Starting from Tseitin’s calculi with seven relations, it constructs encodings by normal algorithms and proves reductions betw…
This paper presents a computational algorithm for refining the trajectory and momentum parameters of a charged particle in a liquid hydrogen bubble chamber, allowing for magnetic field inhomogeneity and, when necessary, momentum loss by slowing down. The method starts from a helical approximation, r…
The paper addresses the construction of finite difference analogues for multidimensional boundary value problems involving derivatives of arbitrary order, with the aim of achieving prescribed polynomial accuracy using the smallest possible number of grid unknowns. It derives an error representation …
This paper proposes a polyasthenospheric model of the Earth’s upper mantle based chiefly on seismological observations from the Kuril, Japan earthquake zone, supplemented by data from strong global earthquakes. The authors jointly analyze travel-time curve derivatives, limiting earthquake magnitudes…
This paper formulates a zero-sum dynamic pursuit game in Euclidean space for two particles with controllable force directions and prescribed force magnitudes, where the pursuer maximizes and the evader minimizes a terminal payoff. It derives a Hamilton-Jacobi type Cauchy equation as a necessary cond…
The paper studies the stable solution of linear functional equations in Hilbert spaces when both the right-hand side and the operator are known only approximately. It formulates a Tikhonov-type regularization functional on a weakly closed convex admissible set, proves existence and uniqueness of its…
The paper develops a theory for interpreting magnetic and gravitational anomalies by treating the inverse problem as the determination of singular points of the harmonic functions describing stationary fields. It compares three analytic-continuation approaches: locating boundaries of analyticity, ex…
This paper analyzes the Tashkent earthquake of April 26, 1966, and its aftershock sequence using macroseismic surveys, records from regional and temporary seismic stations, focal mechanism analysis, and geodetic observations. The main shock reached intensity 8, had an estimated focus near 8 km depth…
The paper studies analytic functions of integer order and finite type in the upper half-plane, with emphasis on completely regular growth and the relation between growth indicators and zero distribution. It gives a canonical representation for such functions, introduces argument-boundary and boundar…
This paper investigates short-range interaction potentials for H and He atoms and hydrogen molecules, motivated by their role in calculating gas transport properties and testing quantum-mechanical interaction calculations. Effective total elastic scattering cross sections were measured for fast neut…
The paper establishes maximum principles for a class of second order hyperbolic equations in a characteristic triangle under explicit sign and integral conditions on the coefficients. These principles are applied to generalized Tricomi type mixed equations, using elliptic maximum arguments, Hopf typ…
This notice provides errata for two previously published articles, one concerning equations of wave fields covariant with respect to the n-dimensional real unimodular group and another concerning a form of distribution for the spectral energy density of thermal radiation. It identifies specific misp…
Relay control systems of the form $$x^{(n)}+a_nx^{(n-1)}+\dotsb+a_2\dot{x}+a_1x=u,\\ u=-\operatorname{sign}(x^{(n-1)}+A_{n-1}x^{(n-2)}+\dotsb+A_2\dot{x}+A_1x),$$ are considered, where $x$ is the controlled coordinate; $u$ is the control action; and $a_1,a_2\dots,a_n$ and $A_1,A_2,\dots,A_{n-1}$ are …
The paper studies an assembly model in queueing theory with several independent Poisson input streams, where completed units require one element from each stream and the remaining elements form a queue vector. Using barycentric coordinates on a simplex lattice, it defines functions that express the …
The paper studies stability of the trivial solution of a general nonlinear system of differential equations under constantly acting perturbations in the neutral Lyapunov case, where the unperturbed system is stable but not assumed asymptotically stable. It proves a Lyapunov-type theorem showing that…
This paper studies a class of singular partial differential operators in a half-space-adjacent domain, involving the Bessel operator and acting in weighted spaces with weight y to the k. Under symmetry, smoothness, and a B-ellipticity positivity condition on the coefficients, the argument derives en…
