Showing 50 of 25357 papers

ON THE SOLUTION OF ITERATED CAUCHY PROBLEMS IN BASIS SERIES

Unknown
1969 SovietRxiv: ru-196901.74832

The paper studies iterated Cauchy problems for singular differential operator equations involving a parameter dependent radial derivative term, a linear operator in auxiliary variables, and spectral constants. It develops basis series representations that express solutions of higher order problems t…

Heat propagation in plasma along a magnetic field (replacement wave)

A. A. Ivanov, L. L. Kozorovitskii, V. D. Rusanov
1969 SovietRxiv: ru-196901.74573

Experiments are reported on heat propagation along a magnetic field in a cylindrical hydrogen or argon plasma column after localized rapid heating by a nonlinear oblique magnetosonic wave. Diamagnetic, magnetic, interferometric, and electric probe measurements show that the plasma pressure perturbat…

GENERAL CONCAVE-CONVEX GAMES

N. T. Tynyanskii
1969 SovietRxiv: ru-196901.74217

The paper studies two-person games on arbitrary convex subsets of finite-dimensional Euclidean spaces with a closed concave-convex payoff function. Using a representation of the payoff as a sum of closed concave-convex functions, it constructs conjugate functions, associated primal and dual optimiza…

LINEAR AND NONLINEAR PARABOLIC SYSTEMS IN THE PLANE

Unknown
1969 SovietRxiv: ru-196901.74206

This paper studies first boundary-value and Cauchy problems for higher-order strongly parabolic linear and nonlinear systems in one spatial dimension. It establishes a priori estimates in anisotropic Sobolev spaces for linear equations with merely measurable bounded coefficients, including L2 bounds…

ON TRIGONOMETRIC SUMS

Unknown
1969 SovietRxiv: ru-196901.74036

The paper studies asymptotic estimates for incomplete trigonometric sums of the form \(\sum_{x\leq P}\exp(2\pi i ax^n/q)\), with \(q\) a high power of a prime and \(P=q^{1/r}\), extending earlier results on short sums and correcting previously misstated formulations. By separating the complete-sum c…

On integral invariants in systems of hydrodynamic type

Unknown
1969 SovietRxiv: ru-196901.74013

The paper defines a broad class of finite dimensional dynamical systems of hydrodynamic type, characterized by quadratic nonlinear equations, conservation of phase volume, and a positive definite quadratic energy integral, as a framework for studying integral invariants relevant to turbulence statis…

ORIENTED CRYSTALLIZATION ON HIGH-POLYMER BOUNDARY LAYERS THAT COPY, BY AN ELECTRET MECHANISM, THE ELECTRIC RELIEF OF THE SURFACE OF SUBSTRATE CRYSTALS

G. I. Distler, S. A. Kobzareva
1969 SovietRxiv: ru-196901.73995

This study examines how amorphous polymer boundary layers can retain and transmit the orienting influence of crystalline substrates during crystallization. Anthraquinone was sublimed onto NaCl and mica surfaces and onto the contact sides of separated polyvinyl chloride and nitrocellulose films prepa…

ON INVARIANTS OF THE GROUP OF TRIANGULAR MATRICES OF ORDER \(n\) WITH ONES ON THE MAIN DIAGONAL

I. B. Brodskii
1969 SovietRxiv: ru-196901.73978

This note studies invariants for the action induced by conjugation of the group of upper triangular unipotent matrices on lower triangular matrices, a problem connected with Kirillov’s reduction of the classification of irreducible unitary representations. It introduces “tensor” sections determined …

ON THE QUESTION OF THE SEISMIC EFFECT OF POWERFUL EXPLOSIONS

Unknown
1969 SovietRxiv: ru-196901.73881

This paper examines why powerful underground explosions can produce damaging seismic effects in buildings at ground vibration velocities well below the commonly used Soviet critical value of 10 cm/sec. It argues that, unlike smaller shallow explosions, large explosions create a much wider hazardous …

ON THE DECOMPOSABILITY OF SPACES

A. G. El'kin
1969 SovietRxiv: ru-196901.73720

This note studies decomposability and maximal decomposability of Hausdorff spaces using dispersion character, pi-bases, characteristic spaces, and relaxations of topologies by ideals. It proves that spaces with sufficiently small pi-weight, and more generally dense-in-itself pi-spaces, are maximally…

ON STOCHASTIC “HEATING” OF A NONLINEAR WAVE

N. N. Filonenko
1969 SovietRxiv: ru-196901.73686

The paper examines stochastic energy pumping into nonlinear waves as an analogue of stochastic acceleration of charged particles in random fields. Using the Korteweg de Vries equation with a weak stationary random external force, it derives an evolution equation for the wave energy and shows that, f…

ON THE COMPLETENESS OF SYSTEMS OF ANALYTIC FUNCTIONS GENERATED BY SUCCESSIVE DERIVATIVES OF ANALYTIC FUNCTIONS

I. I. Ibragimov
1969 SovietRxiv: ru-196901.73344

The paper studies completeness in domains of systems of analytic functions obtained by taking successive derivatives with respect to a parameter in a generating function \(F(z,u)=\sum \varphi_n(z)u^n\), evaluated at prescribed nodes. Using the Abel Goncharov interpolation formula, it derives criteri…

PROBLEMS OF STATISTICAL PHYSICS IN STRONGLY ELONGATED BODIES

Yu. S. Tyupkin, A. S. Schwarz
1969 SovietRxiv: ru-196901.73282

The paper examines statistical-physics problems in strongly elongated Bose systems, questioning claims that elongation by itself lowers the onset temperature of Bose condensation, superfluidity, or superconductivity. For an ideal Bose gas, the authors analyze particle occupation, thermodynamic funct…

DIFFRACTION THEORY OF SHADOW PHOTOMETRIC KNIFE-EDGE AND SLIT METHODS

L. A. Vasil'ev, È. P. Kazandjan, V. S. Sukhorukikh
1969 SovietRxiv: ru-196901.73265

This paper develops a diffraction-theoretical treatment of shadow photometric knife-edge and slit methods, in which geometrical optics predicts a linear relation between ray deflection angle and image-plane illumination. Using the Huygens-Fresnel principle for the focal plane and image plane of the …

ON THE QUESTION OF MEASURING THE AMOUNT OF A MEDIUM IN A CLOSED VOLUME

B. N. Petrov, V. A. Viktorov, B. V. Lunkin
1969 SovietRxiv: ru-196901.73092

The paper addresses measurement of the quantity of a dielectric medium distributed arbitrarily within a closed vessel, where conventional readings may depend on the shape and position of the filled region. It develops a resonant electromagnetic method in which metallic surfaces or lines form a field…

CRYSTAL STRUCTURE OF SYNTHETIC Na,Sc-SILICATE

S. M. Skehat, V. I. Simonov, N. V. Belov
1969 SovietRxiv: ru-196901.73077

The paper reports the synthesis and crystal-structure determination of the scandium sodium diorthosilicate Na3Sc[Si2O7], obtained as transparent rhombic single crystals in the Na2O, Sc2O3, SiO2, H2O system. X-ray diffraction, Patterson and electron-density syntheses, and least-squares refinement in …

EXPONENTIAL DECAY OF THE SOLUTION OF THE WAVE EQUATION IN THE EXTERIOR OF AN ALMOST STAR-SHAPED DOMAIN

V. Ya. Ivrii
1969 SovietRxiv: ru-196901.72868

The paper studies local energy decay for the exterior Dirichlet problem for the wave equation in odd-dimensional Euclidean space outside a bounded obstacle. It introduces the class of almost star-shaped domains, defined by the existence of a family of strictly convex level surfaces satisfying a geom…

HYPERFINE STRUCTURE OF BRAGG MAXIMA IN MÖSSBAUEROGRAPHY

M. A. Andreeva, R. N. Kuz'min
1969 SovietRxiv: ru-196901.72793

This paper analyzes the hyperfine structure of Bragg maxima in Mössbauer diffraction and compares the information obtainable from diffraction peaks with that from conventional resonance absorption. It argues that, although the energy positions of hyperfine components are governed by the same nuclear…

ON A CONDITION FOR REGULARITY OF A GAUSSIAN STATIONARY PROCESS

I. A. Ibragimov, V. N. Solev
1969 SovietRxiv: ru-196901.72627

This note studies Kolmogorov’s weak dependence condition for the past and future of Gaussian stationary processes, expressed through the coefficient beta. For discrete time, it gives a necessary and sufficient spectral characterization: the spectral density must factor as the squared modulus of a po…

THE INFLUENCE OF THE CHARACTER OF INTRAMOLECULAR ORIENTATIONAL MOTION ON MAGNETIC RELAXATION IN SOLIDS

M. R. Zaripov, M. M. Bildanov, G. M. Kadievskii
1969 SovietRxiv: ru-196901.72569

This paper examines how different types of intramolecular orientational motion affect proton spin-lattice magnetic relaxation in crystalline amino acids. Measurements of relaxation times over a range from 77 K to the melting point show separate low-temperature and high-temperature minima, attributed…

On the Distribution of the Extreme Terms of a Variation Series

Yu. N. Blagoveshchenskii
1969 SovietRxiv: ru-196901.72044

This paper studies the asymptotic distribution of extreme order statistics \(x_{kn}\) when \(k\to\infty\) and \(k/n\to 0\), emphasizing conditions for both integral and local asymptotic normality. It introduces a class of locally regular distributions, formulated through the behavior of \(p_F(\lambd…

PHRAGMÉN–LINDELÖF TYPE THEOREMS FOR SOLUTIONS OF SOME DIFFERENTIAL EQUATIONS IN AN INFINITE SLAB

V. M. Borok
1969 SovietRxiv: ru-196901.71769

This paper establishes Phragmén-Lindelöf type estimates for solutions of second order evolution equations with constant complex coefficients in an infinite slab, under two-point boundary conditions in the time variable. For equations previously characterized as well posed, it shows that suitably str…

ON AN INVERSE PROBLEM IN DIFFRACTION THEORY

G. D. Malyuzhinets
1969 SovietRxiv: ru-196901.71624

This note formulates an inverse problem for scalar diffraction of a plane wave by a sphere whose surface admittance is expanded in Legendre polynomials with coefficients depending on the nondimensional parameter kr0. The objective is to choose these coefficients so that, in the low-frequency limit, …

DIFFUSION IN THE Cu—Zn SYSTEM UNDER THE ACTION OF ALTERNATING DEFORMATIONS

A. V. Kulemin, A. M. Mitskevich
1969 SovietRxiv: ru-196901.71485

This paper investigates whether ultrasonic alternating deformation accelerates diffusion in the Cu-Zn system, focusing on growth of gamma and epsilon intermetallic phases around zinc inserts in copper rods. Copper specimens were subjected to longitudinal ultrasound at 18.6 kHz during isothermal hold…

A PRIORI ESTIMATES OF SOLUTIONS OF ELLIPTIC EQUATIONS IN THE CLASS OF ANALYTIC FUNCTIONS AND THEIR APPLICATIONS TO THE CAUCHY–POISSON PROBLEM

V. I. Nalimov
1969 SovietRxiv: ru-196901.71348

This paper establishes a priori estimates up to the boundary for solutions of elliptic boundary value problems in norms adapted to functions analytic in tangential variables. Using Schauder-type estimates and commutator bounds, it proves an estimate for uniformly elliptic operators in a layer with b…

REPRESENTING SPACES FOR THE \(K\)-FUNCTOR WITH COEFFICIENTS

V. M. Bukhshtaber
1969 SovietRxiv: ru-196901.71233

The paper studies complex K-theory with coefficients for an odd prime p, relating Adams-Toda homotopy operations to differentials in the Atiyah-Hirzebruch spectral sequence. It constructs cellular spaces representing mod p K-theory with prescribed homotopy groups and uses them to define 2(p-1)-perio…

ELECTRON PARAMAGNETIC RESONANCE OF Mn\(^{2+}\) AND Gd\(^{3+}\) IONS IN THE CHALCOGENIDE GLASSES TlAsSe\(_2\) AND TlAsS\(_2\) IN THE 2 AND 0.8 cm BANDS

I. V. Chepeleva
1969 SovietRxiv: ru-196901.71160

Electron paramagnetic resonance spectra of Mn2+ and Gd3+ ions in TlAsSe2 and TlAsS2 chalcogenide glasses were studied in the 2 and 0.8 cm bands and compared with earlier 3 cm results to clarify the origin of anomalous lines with effective g factors greater than 2. The frequency dependence of the Mn2…

THE MAXIMUM PRINCIPLE IN THE CLASS OF VARIATIONS SMALL IN ABSOLUTE VALUE, FOR OPTIMAL CONTROL PROBLEMS WITH MIXED CONSTRAINTS OF EQUALITY AND INEQUALITY TYPE

A. Ya. Dubovitskii, A. A. Milyutin
1969 SovietRxiv: ru-196901.71137

This note derives necessary optimality conditions for an optimal control problem with fixed endpoints, differential dynamics, mixed equality constraints, and set constraints of inequality type, considering variations that are small in absolute value. Under stated smoothness, cone, and nondegeneracy …

ELLIPTIC PSEUDODIFFERENTIAL OPERATORS ON A CLOSED MANIFOLD DEGENERATING ON A SUBMANIFOLD

M. I. Vishik, V. V. Grushin
1969 SovietRxiv: ru-196901.70200

This paper studies pseudodifferential operators on a smooth compact manifold that are elliptic away from a hypersurface but degenerate on it in a prescribed quasihomogeneous manner. It introduces adapted Sobolev-type spaces and analyzes boundary and coboundary conditions imposed on the degeneracy su…

ON THE THEORY OF BRANCHING SYSTEMS

Academician B. N. PETROV, G. A. STEPAN’YANTS
1969 SovietRxiv: ru-196901.69718

The paper develops a probabilistic framework for branching systems described by ordinary differential equations whose right-hand sides may change across prescribed time intervals according to probability measures depending on prior states. It defines state spaces, branching solution processes, reali…

Features of Diffuse X-ray Scattering at the Zone Stage of Aging of the $\mathrm{AlAg}$ Alloy

G. V. Kleshchev, A. I. Sheinkman, D. V. Shumilov, A. E. Vanin
1969 SovietRxiv: ru-196901.69419

This paper investigates diffuse X-ray scattering in AlAg single crystals containing 20 and 40 wt.% silver during the zone stage of aging. Using the crystal-rotation method after quenching and short tempering, the authors reconstruct diffuse-scattering regions near multiple reciprocal-lattice nodes a…

OPTIMAL QUESTIONNAIRES WITH UNEQUAL COSTS OF QUESTIONS

Unknown
1969 SovietRxiv: ru-196901.69399

The paper studies optimal questionnaires for identifying one event from a finite weighted set when questions may have different arities and unequal costs. It models a questionnaire as a rooted tree or pragraph, defines the expected traversal cost as the weighted sum of path costs, and analyzes trans…

RADIATION OF AN ELECTRON–POSITRON PAIR

V. E. Pafomov
1969 SovietRxiv: ru-196901.69239

The paper calculates the angular and spectral radiation of a relativistic electron-positron pair moving through the atmosphere while undergoing multiple scattering in the presence of the Earth’s magnetic field. It derives averaged expressions for two linear polarizations, including separate particle…

SYSTEMS OF SECOND-ORDER PARTIAL DIFFERENTIAL EQUATIONS OF COMPOSITE TYPE WITH ONE DOUBLE FAMILY OF REAL CHARACTERISTICS

A. Dzhuraev
1969 SovietRxiv: ru-196901.69094

The paper studies systems of second-order partial differential equations of composite type in two variables, represented by a complex equation whose characteristics include one double real family and two imaginary families. It shows that a general equation of this type can be reduced, under suitable…

VIBRATIONAL RELAXATION OF OSCILLATORS WITH CLOSE FREQUENCIES

E. I. Dashevskaya
1969 SovietRxiv: ru-196901.69087

This paper examines vibrational relaxation in collisions of two diatomic molecules modeled as harmonic oscillators with close but not necessarily identical frequencies. By retaining quasiresonant one-quantum exchange terms while neglecting strongly adiabatic single-molecule and two-quantum transitio…

THERMAL PHENOMENA IN THE FIELD OF A TROPICAL HURRICANE

V. V. Shuleikin
1969 SovietRxiv: ru-196901.68877

This paper examines thermal processes in a tropical hurricane, focusing on how heat from a warm ocean surface supplies energy to the hurricane core between the outer boundary of the eye and the radius where vertical motion changes sign. Using a previously derived simplified hydrodynamic model, hypso…

THE CRYSTAL STRUCTURE OF RAMSAITE

Chin-khan, M. A. Simonov, N. V. Belov
1969 SovietRxiv: ru-196901.68863

The paper reports an independent X-ray refinement of the crystal structure of ramsaite, Na2Ti2Si2O9, undertaken to verify and improve an earlier closest-packing-based model. Single-crystal Weissenberg data and three-dimensional least-squares refinement in space group Pnca gave atomic coordinates for…

LOCAL PROPERTIES OF THE SOLUTION OF THE TRANSPORT EQUATION

T. A. Germogenova
1969 SovietRxiv: ru-196901.68648

This paper studies local smoothness, differentiability, and singular behavior of generalized solutions to an inhomogeneous one-speed transport equation in a bounded three-dimensional domain decomposed into finitely many subdomains with piecewise smooth interfaces. Using integral representations alon…

The Sample Mean as an Estimate of a Location Parameter under Certain Losses Different from Quadratic

A. A. Zinger, A. M. Kagan, L. B. Klebanov
1969 SovietRxiv: ru-196901.68288

This paper studies when the sample mean is an admissible estimator of a one-dimensional location parameter under loss functions other than the quadratic loss. For Laplace loss, and for samples from a distribution with a continuously differentiable unimodal density, the authors derive an integral con…