Translated papers from the Chinese Preprint site, Chinaxiv
Showing 50 of 15540 papers
Generated abstract This paper analyzes deep seismic sounding data from a 214 km profile in Kazakhstan to evaluate how deterministic and random heterogeneities in the Earth’s crust affect first-arrival amplitudes and travel times. The authors formulate a statistical crustal model in which longitudinal-wave velocity is …
Generated abstract This note studies a class of singular integral operators in a half-space whose kernels have singularities on a hypersurface and are related to the generalized shift operator. The authors formulate the operators in several equivalent forms, identify a necessary and sufficient cancellation condition f…
Generated abstract This paper develops consequences of a previously established local criterion for the existence of wave operators for pairs of self-adjoint operators. It formulates sufficient trace-class conditions ensuring subnormality and normality, including unitary equivalence of absolutely continuous parts, and…
Generated abstract This note defines a class of strictly hyperbolic difference operators intended to preserve key properties of strictly hyperbolic differential operators on sequences of grids. Using Fourier representations on the grid, it formulates homogeneity, regularity, and root separation conditions analogous to…
Generated abstract The paper addresses the decomposition of direct products of irreducible representations of crystal space groups, a problem needed for applying selection rules and constructing exciton and related states in solid-state physics. It formulates a method, mainly for symmorphic space groups, for determini…
Generated abstract This paper studies two person zero sum games whose payoff is a continuous function on the unit square, focusing on the size and structure of the set of games with unique optimal strategies. It proves that games with a unique solution and finite spectra of optimal strategies are dense in the space of…
Generated abstract The paper studies the existence, uniqueness, and construction of periodic solutions for differential equations in a complex Banach space with coefficients or nonlinear terms periodic in time. It develops fixed point operators related to Cesari’s method, first deriving criteria for first order linear…
Generated abstract The paper studies continuous mappings under which covering dimension is constrained more sharply than in classical Hurewicz-type inequalities. It introduces the notion of a strongly closed mapping and proves that if such a mapping sends a normal space onto a paracompact space, with image dimension a…
Generated abstract This paper introduces a generalized continuous interval, defined through connectedness properties of point deletions, and shows how such spaces carry natural linear orders and interval-type topologies. It characterizes ordered sets that admit suitable T1 topologies making them segments, proves a con…
Generated abstract The paper applies model theory and nonstandard analysis to questions of topological equivalence for Banach spaces, revisiting the theorem that all infinite-dimensional separable Banach spaces are homeomorphic. It constructs nonstandard Banach spaces through internal function spaces and ultrapowers, …
Generated abstract This paper formulates a generalized rheological model for rocks intended to represent elasticity, viscous and plastic flow, elastic aftereffect, and shear and tensile strength under variable physical conditions. The model combines Burgers and Shvedov, Bingham elements and derives tensor deformation …
Generated abstract The paper studies almost sure growth rates for sums of independent random variables under moment conditions expressed through a general even increasing function g. It proves upper bounds of the form S_n = o(g^{-1}(A_n psi(A_n))) for functions psi whose associated series converges, with appropriate c…
Generated abstract This paper studies sequential estimation plans for basic Markov processes, focusing on first-entry stopping rules and the extent to which such plans are determined by properties of their stopping times. For binomial and multinomial schemes, Poisson processes, and Brownian motion with unknown drift, …
Generated abstract This note studies the enumeration of precomplete classes in finite k-valued logics, a central component of completeness criteria for such logics. Using Rosenberg’s classification of precomplete classes into six families, the authors reduce the asymptotic count to the enumeration of central predicate…
Generated abstract Vinogradov develops a variant of Morse theory for incomplete spaces of the form M setminus K, where M is complete and K is a closed subset, by introducing responsible and noncritical points and proving a fundamental homotopy invariance lemma under admissibility conditions. The method is applied to t…
Generated abstract This paper studies nonassociative algebras over a fixed commutative associative ring with identity that contain no nilpotent elements, in the sense that x squared equals zero only for x equal to zero. It gives necessary and sufficient conditions, involving a conditional associativity type identity a…
Generated abstract This paper studies minimax optimization problems of the form minimizing the maximum of a smooth function over an auxiliary set. It derives first-order stationarity conditions using directional derivatives of the max function and replaces generally discontinuous criteria by equivalent continuous func…
Generated abstract The paper introduces pseudodevelopable spaces, defined by the existence of a sigma-biconservative pairbase, and studies their role in problems concerning symmetrizability. It gives equivalent characterizations of this class, establishes preservation under hereditary operations, countable products, c…
Generated abstract This paper analyzes the spectral composition of induced radiation generated in a laser resonator with frequency-dependent losses. Using stationary rate equations for photon populations and inverted population density, the authors derive conditions for the number of oscillating modes when the resonat…
Generated abstract This paper analyzes stepwise ionization of atoms in discharge plasmas under conditions of large tube dimensions, high electron density, and electron temperatures small compared with the ionization energy. It derives scaling relations showing how the stepwise ionization constant depends on electron t…
Generated abstract The paper develops a generalization of Cauchy’s fundamental theorem for finite-dimensional associative algebras over the real numbers. It defines line integrals of continuous algebra-valued functions along rectifiable arcs and proves that, for every closed rectifiable contour, the integral of a powe…
Generated abstract The paper studies boundary values and traces of generalized solutions of properly elliptic differential equations in a bounded smooth domain. Using Sobolev type spaces with boundary components and integration by parts identities, it proves equivalence between a norm involving interior Sobolev regula…
Generated abstract The paper proposes a method for treating extremal problems in the theory of univalent functions by applying Pontryagin’s maximum principle. Using the Löwner equation, it reduces the problem of minimizing the real part of a prescribed coefficient of \(G(f(z))\) over the class of normalized univalent …
Generated abstract This paper develops iterative methods for nonlinear systems of finite difference equations, with emphasis on difference analogues of strongly elliptic boundary value problems in a parallelepiped. It formulates abstract monotonicity and differentiability conditions in finite-dimensional Hilbert space…
Generated abstract The paper presents algorithms for the square assignment problem, seeking one matrix element in each row and column with minimum total sum. It introduces a vector adjustment framework in which selected row bases are maintained as minimal relative to column potentials, and an iteration reduces the num…
Generated abstract This paper studies estimation of a shift parameter for distributions supported on a bounded interval, with emphasis on equivariant Pitman estimates and their sequential analogues. It proves an upper bound for the mean squared error of the fixed-sample Pitman estimate in terms of the sample size and …
Generated abstract The paper analyzes why the sputtering coefficient of a solid target under ion bombardment initially increases with incidence angle but reaches a maximum and then decreases at grazing incidence. Using focuson theory and a scattering model that includes refraction of incident particles in the medium, …
Generated abstract This paper examines the generation of surface waves when an acoustic plane wave is scattered by a statistically rough interface between two liquid media. Using a perturbation approach modified to include attenuation of waves initially scattered in grazing directions, it derives effective boundary im…
Generated abstract This paper studies whether exhaustive search can be avoided when computing a function using an oracle for its own graph, where computation proceeds by questions of the form “is the value at this argument equal to this number?” It formalizes guessing strategies by Turing machines with such oracles, d…
Generated abstract The article examines whether discrepancies between repeated gravity measurements in the Aral-Caspian region can be interpreted as secular changes in gravity rather than instrumental or reference-point errors. Using gravimetric observations from 1954 to 1966 tied to high-precision control points, the…
Generated abstract This paper studies nonlinear multidimensional differential equations in finite-dimensional Banach spaces with almost periodic dependence on the independent variable. It derives algebraic conditions, based on a Frobenius-type complete integrability criterion and power-series representations, for comp…
Generated abstract The paper proposes a macromodel for evaluating the efficiency of large information control systems consisting of a controlled object and a controlling subsystem linked by a flow of control information. It defines efficiency as the difference between the positive effect released in the object and the…
Generated abstract This note extends Glicksberg’s generalization of Kakutani’s fixed point theorem in locally convex Hausdorff linear topological spaces to a broader class of set-valued mappings. After recalling closed multifunctions, it introduces a weaker notion of partial closedness, defined by a limiting condition…
Generated abstract The paper studies perturbations of the continuous spectrum for the multiplication operator in \(L_2(-\infty,\infty)\) under a class of infinite-dimensional completely regular perturbations represented as \(V=A^*B\). Using an operator-valued function \(K(\zeta)=1+BS_\zeta A^*\), it characterizes nonr…
Generated abstract This paper examines whether finite amplitude drift waves in an inhomogeneous magnetized plasma can exhibit nonlinear excitation mechanisms absent from linear theory. Using a drift kinetic treatment with quasineutrality, the authors analyze a standing drift wave and isolate the contribution of electr…
Generated abstract This paper studies defect indices and self-adjointness of minimal symmetric differential operators with polynomial coefficients in spaces of square-integrable functions. By representing the operators in bases of Hermite functions, the analysis reduces them to infinite Jacobi matrices with matrix coe…
Generated abstract The paper studies closed convex hypersurfaces in Euclidean space whose elementary symmetric function of the principal radii of curvature is prescribed as a function of the exterior normal. It proves an a priori upper estimate for every radius of normal curvature in terms of the corresponding mean ra…
Generated abstract This paper studies infinitesimal bendings of a surface with boundary and positive exterior curvature in a three-dimensional Riemannian space, subject to a generalized sliding boundary condition. Using isothermally conjugate coordinates, the geometric problem is reduced to boundary value problems for…
Generated abstract This paper studies exponential stabilization of finite-dimensional linear control systems with respect to a prescribed positive definite quadratic form and a prescribed decay rate. It formulates algebraic conditions under which feedback matrices can be chosen so that the Lyapunov inequality holds wi…
Generated abstract The paper develops a general framework for applying the Bogolyubov-Krylov averaging method to evolution equations, including equations with retarded arguments and generalized time transformations. It defines averaged right hand sides and averaged generalized times in suitable spaces of continuous an…
Generated abstract The paper studies the asymptotic stability of nonlinear pulse systems with a single pulse element whose pulse frequency is modulated by the input signal and includes a dead zone. The system is formulated as a nonlinear integral equation with exponentially decaying impulse response, and Popov-type fr…
Generated abstract The paper studies the large-time behavior of solutions to a two-component quasilinear hyperbolic conservation system under the Lax genuine nonlinearity condition. For smooth initial data that approach two constant states at spatial infinity and satisfy a nondegeneracy and monotonicity condition in R…
