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
This paper studies general mixed boundary value problems and the Cauchy problem for broad classes of linear parabolic systems with discontinuous coefficients in domains separated by an internal interface. It formulates algebraic complementing conditions for boundary, initial, and conjugation operato…
This paper proposes that late-type flare stars may produce detectable cosmic X-ray radiation during flares, motivated by the appearance of the He II 4686 Å line and the implied presence of sufficiently energetic photons or particles. It develops an inverse Compton interpretation in which infrared ph…
This paper studies measure-preserving dynamical systems that can be approximated by periodic, in particular cyclic, transformations with specified rates, and relates these approximation rates to entropy and spectral properties. It proves that sufficiently fast cyclic approximation implies zero entro…
The study investigates the ionic composition of the positive column of glow discharges in helium and argon with a small admixture of mercury vapor at pressures from 5 to 50 mm Hg. Using a mass spectrometer designed for high pressure gas phase ion processes, the authors examine pressure and current d…
This paper examines the negative resistance regime and the subsequent stable stimulated state in sublimated electroluminescent zinc sulfide films at 77 K. Using electroluminescence, probe measurements of the voltage drop in the phosphor, current voltage characteristics, thermoluminescence, and after…
This paper examines how postglacial uplift can be used to estimate the dynamic viscosity of the asthenosphere, arguing that earlier estimates neglected the finite thickness of the subcrustal flowing layer. The authors model the uplift of an axisymmetric depression in a viscous incompressible layer o…
This paper reports an experimental investigation of the stability of a cantilevered rod subjected to a follower compressive force, a problem previously treated mainly by theory for nonconservative loading. The setup used compressed air jets mounted at the free end to generate the follower force, wit…
The paper examines propagation of high frequency waves governed by a hyperbolic second order equation whose coefficients are random functions of space and time. Using a geometrical optics approximation, it separates the eikonal phase into an averaged part and a random fluctuation, expresses the latt…
This paper studies a coupled operator system of the form x equals mu A(x,y), y equals B(x,y) in products of Banach spaces, using Krasnosel’skii’s topological methods for completely continuous vector fields. It establishes formulas for rotations and fixed point indices in terms of a reduced linear op…
The paper studies bounds for the number of states arising in the optimal determinization of finite orthogonal systems of directed graphs, a construction motivated by automaton synthesis. Extending earlier one graph estimates of Lyubich and Ostrovskii, it proves an upper bound for systems with severa…
This note studies positive harmonic functions for convolution-type operators on nilpotent groups, extending known descriptions from the abelian case. Under a support-generation condition on the transition function, the argument uses compactness of normalized positive harmonic functions, Choquet repr…
This paper formulates necessary optimality conditions for controlled systems containing distributed-parameter elements, where the state is governed by parabolic partial differential equations with controlled boundary dynamics and additional ordinary differential equations at the endpoints. Extending…
The paper proves that every closed image of a metric space admits a condensation onto a metrizable space, with the essential interest lying in the nonseparable case. The proof uses a decomposition theorem of Lashnev to isolate a countable union of discrete sets over which fibers may fail to be compa…
This paper studies almost everywhere differentiability for functions in generalized Sobolev classes \(W_p^l(G)\), allowing the highest order derivatives to be measures when \(p=1\). It defines a complete differential of order \(l\) through convergence of rescaled remainders in a Banach function spac…
The paper studies linear operators on decomposed Banach spaces equipped with an indefinite J-metric, focusing on J-nonexpanding and related J-isometric operators defined on arbitrary linear manifolds rather than necessarily on the whole space. It establishes elementary structural properties of negat…
This note develops a model for constructing depreciation charges for a stationary machine fleet subject to an arbitrary stationary load. Machines are represented by their remaining resource, loads and assignments by distribution functions, and stationarity is expressed through measures linking resou…
This paper develops necessary conditions for local extrema of differentiable functionals on subsets of Banach spaces using the cone of admissible directions, with particular attention to pseudoconvex sets that include convex sets and boundaries of convex bodies. It derives extremum conditions for Fr…
This paper studies a class of linear dynamic programming problems in which admissible controls may be unbounded and are treated as generalized functions, while phase coordinates may be discontinuous. It formulates the control system with linear dynamics, endpoint conditions on linear manifolds, and …
This paper analyzes the deposition pattern produced when a cloud of interacting particles settles through the atmosphere and is gradually diluted by turbulent diffusion, causing separated particles to fall with their Stokes velocity and form a moving “dusting” source. The authors formulate and solve…
This paper develops a one-electron perturbation treatment of the short-wavelength region of x-ray K-absorption spectra for single crystals and polycrystalline samples. The crystal potential is separated into a quasiatomic central part, treated exactly, and a residual crystalline field, treated to fi…
The paper constructs variational difference schemes with improved boundary approximation for the third boundary-value problem for a linear two-dimensional second-order elliptic equation, with corresponding applicability to the first boundary-value problem. The method uses a polygonal domain fitted t…
This paper studies point sets called \(\{k;n\}_q\)-arcs in finite projective Galois planes, focusing on upper bounds for \(k\), existence cases, and completeness. Using Diophantine systems associated with secants through absolute and external points, it gives another proof of Barlotti’s bounds and a…
This paper studies the mean-square closure of integral functionals of the form obtained by integrating a Borel function of a stationary zero-mean Gaussian process over a finite interval. Using expansions in normalized Hermite polynomials and estimates for powers of the correlation function, it gives…
The paper studies uniqueness in an inverse problem of potential theory: determining a density in a given open set from the exterior values of its metaharmonic potential, an integral equation of the first kind. It proves that although uniqueness need not hold in general, it does hold for certain clas…
This note gives intrinsic characterizations of those T1 spaces that arise as closed continuous images of metric spaces, and of complete metric spaces. It introduces hereditarily conservative systems of closed sets and almost refining sequences of closed covers, showing that a T1 space is a closed im…
The paper studies solvability and regularity for a class of quasilinear elliptic boundary value problems whose principal part is a linear uniformly elliptic operator of order 2m with first boundary conditions. Using homeomorphism theorems for elliptic operators in Sobolev scales, resolvent estimates…
The paper studies bivariate distributions with prescribed normal marginals represented by bilinear Hermite expansions and defines a generalized normal correlation through nonnegativity of the resulting density. It proves that such an expansion is a valid density if and only if its coefficients are t…
This paper investigates how the noncentral gravitational field of the Moon affected the orbit of the artificial lunar satellite Luna-10, while also accounting for perturbations from the Earth, the Sun, and planets. Trajectory measurements from the satellite’s active lifetime in April to May 1966 wer…
This paper formulates the detuning of a finite vibrational system from a resonance-dangerous frequency interval as a convex programming problem in the space of adjustable stiffnesses. Using variational properties of eigenvalues, it characterizes the antiresonance region as convex, gives a parametric…
The paper studies a class of singular integral equations with a shift on a finite union of Lyapunov contours, where the shift is an orientation preserving homeomorphism generating a finite cyclic group. By reducing the scalar shifted equation to an associated system of singular integral equations an…
This paper examines how the operational metric of space-time may be defined when the only available physical signals are governed by nonlinear field equations, for which Lorentz invariance need not imply a constant signal velocity. Using a scalar field derived from a variational principle, it argues…
The paper develops a method for estimating fractional powers and related operators for weakly positive operators in Banach and Lebesgue spaces. It proves interpolation type inequalities for seminorms on domains of fractional powers, derives bounds for operators of the form BA to a negative fractiona…
This paper studies order-preserving automorphisms of the partially ordered set of submultiplicative norms on the ring of real square matrices of fixed order. It extends the setting to generalized norms associated with subrings, then analyzes the induced action on minimal one-dimensional subrings, ra…
The paper formulates and solves an inverse mixed boundary value problem for an analytic function in a simply connected domain whose boundary consists of prescribed polygonal parts, up to unknown stretching factors, and unknown arcs of prescribed lengths. Boundary data on the arcs prescribe the real …
The paper examines generalized Lagrange equations derived from identities for higher time derivatives of kinetic energy and from generalized forms of d’Alembert’s principle, with particular attention to the Nielsen and Tsenov equations. It shows how these equations can be transformed, by methods ass…
This paper develops the method of indexials for finite groups, addressing criteria for the existence of subgroups of prescribed orders, including cases where subgroup order and index need not be relatively prime. Building on earlier results on regular indexials, it introduces supplementary subgroups…
This paper studies when metrizability is preserved under quotient s-mappings from metrizable or locally separable metrizable spaces. It proves that a separable regular first-countable quotient s-image of a metric space is metrizable, extending Stone’s theorem, and shows that a regular weakly paracom…
The paper studies transcendence and algebraic independence of values of E-functions that satisfy second order linear nonhomogeneous differential equations. It introduces a lemma reducing certain algebraic differential relations for solutions of nonhomogeneous first order systems, and consequently hi…
The paper analyzes the covariant form of the Dirac equation in Riemannian space using tetrads, Lorentz group generators, and spinor parallel transport. By squaring the curved-space Dirac equation, it identifies an additional curvature-dependent term in the effective mass relation, interpreted as a s…
The paper extends the one-dimensional factorization of the scattering matrix for the Schrödinger operator to the multidimensional case. It introduces solutions defined through a modified Green function depending on a direction parameter and, assuming unique solvability of the associated integral equ…
The paper studies absolutely monotone segment functionals on polynomials of bounded degree, distinguishing nodal functionals with unique extremal structure from amorphous functionals lacking a definite nodal decomposition. It gives criteria, in terms of the number and placement of quota nodes, for w…
This study examines the dark conductivity and photoconductivity of bilirubin layers, a bile pigment structurally related to porphyrin pigments but containing an open conjugated chain. Bilirubin films between platinum electrodes were measured in high vacuum and under controlled oxygen pressures, with…
This note studies mixed best approximation of analytic functions in two opposite angular domains by entire functions of prescribed order and type in an \(L_p\) metric. Using a principle that reduces approximation questions in such unbounded domains to estimates on the boundary lines, the authors def…
