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Expectations of the High Performance Computing Cluster File System Selection Lobachevskii J. Math. Pub Date : 2024-03-25 O. S. Aladyshev, B. M. Shabanov, A. V. Zakharchenko
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Global Existence of Classical Solutions to an Aggregation Model with Logistic Source Lobachevskii J. Math. Pub Date : 2024-03-25 J. O. Takhirov, B. B. Anvarjonov
Abstract In this article, a class of systems of cross-diffusion chemotaxis is studied. Using the entropy dissipation method and assuming that chemotactic sensitivity mainly separates cell density and chemical signal, it is established the existence of global solutions with cross-diffusion effects. The global existence and uniqueness of the classical solutions of this system is proved by the contraction
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On Conditions for the Approximability of the Fundamental Groups of Graphs of Groups by Root Classes of Groups Lobachevskii J. Math. Pub Date : 2024-03-25 E. V. Sokolov
Abstract Suppose that \(\Gamma\) is a non-empty connected graph, \(\mathfrak{G}\) is the fundamental group of a graph of groups over \(\Gamma\), and \(\mathcal{C}\) is a root class of groups (the last means that \(\mathcal{C}\) contains non-trivial groups and is closed under taking subgroups, extensions, and Cartesian powers of a certain type). It is known that \(\mathfrak{G}\) is residually a \(\mathcal{C}\)-group
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The Hilbert Problem in a Half-plane for Generalized Analytic Functions with a Super-singular Point on the Contour of the Boundary Condition Lobachevskii J. Math. Pub Date : 2024-03-25 P. L. Shabalin, E. N. Khasanova
Abstract In this paper, we study an inhomogeneous Hilbert boundary value problem with a finite index for one generalized Cauchy–Riemann equation with a supersingular point on the contour of the boundary condition. We obtain a structural formula for the general solution of this equation under constraints leading to an infinite index of the accompanying Hilbert boundary value problem for analytic functions
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A Special Type of Anti-invariant Riemannian Submersions Lobachevskii J. Math. Pub Date : 2024-03-25 M. Gülbahar, E. Erkan, F. Maksut
Abstract A special type of anti-invariant Riemannian submersions is investigated. It is shown that the base space of an anti-invariant submersion is an almost contact metric manifold. The basic properties of these anti-invariant Riemannian submersions are presented. Some relations involving the Riemannian curvature invariants of these submersions are obtained.
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On Annihilators and Quasi-Frobenius Rings Lobachevskii J. Math. Pub Date : 2024-03-25 Tran Hoai Ngoc Nhan, M. Tamer Koşan, Truong Cong Quynh
Abstract Ginn and Moss proved that a two sided Noetherian ring with essential right socle is right and left Artinian. We prove that \(R\) is a right Artinian ring whose the Jacobson radical is equivalent to the right singular ideal if and only if \(R\) is a right Noetherian ring whose the left socle is essential as a right ideal. We also give some characterizations of quasi-Frobenius rings in terms
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Mixed Problem for a Nonlinear Parabolic Equation with Involution Lobachevskii J. Math. Pub Date : 2024-03-25 T. K. Yuldashev
Abstract In this paper, we consider a nonlinear parabolic differential equation with involution. With respect to spatial variable is used Dirichlet boundary value conditions and spectral problem with involution is obtained. Eigenvalues and eigenfunctions of the spectral problems are found. The Fourier series method of separation of variables is applied. The countable system of nonlinear integral equations
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Projective Disk and the Action of SL( $$\boldsymbol{3,\mathbb{R}}$$ ): Exploring Orthogonality Lobachevskii J. Math. Pub Date : 2024-03-25 Debapriya Biswas, Ipsita Rajwar
Abstract This paper presents a comprehensive investigation of the mappings establishing correspondences between the elliptic, parabolic, and hyperbolic upper half planes and the interior, boundary, and exterior of the projective unit circle in \(\mathbb{RP}^{2}\). Characterizations of Möbius-invariant cycle images are provided, and the definition of orthogonality for quadrics within the projective
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Approximative Solar Properties of Sets and Local Geometry of the Unit Sphere Lobachevskii J. Math. Pub Date : 2024-03-25 A. R. Alimov
Abstract Given a nonempty subset \(M\) of a normed space, a point \(s\) of the unit sphere is said to be \(M\)-acting if some ball \(B(x,r)\) touches the set \(M\) by an analogue \(y\) of the point \(s\), i.e., \(s=(y-x)/r\). Balayage theorems of geometric approximation theory are obtained in terms of \(M\)-acting points. The concepts of \(M\)-strictly convex and \(M\)-uniformly convex spaces are introduced
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Solvability of Nonlinear Equilibrium Problems for Timoshenko-type Shallow Shells in Curvilinear Coordinates Lobachevskii J. Math. Pub Date : 2024-03-25 S. N. Timergaliev
Abstract We prove the existence of solutions to the boundary value problem of equilibrium of elastic shallow inhomogeneous isotropic shells with free edges in the framework of Timoshenko beam model. The research is conducted in arbitrary curvilinear coordinates. The boundary value problem is reduced to a nonlinear operator equation with respect to generalized displacements in a Sobolev space. The solvability
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Ricci Bi-Conformal Vector Fields on Lorentzian Walker Manifolds of Low Dimension Lobachevskii J. Math. Pub Date : 2024-03-25 Mahin Sohrabpour, Shahroud Azami
Abstract In the present paper, we classify the Ricci bi-conformal vector fields on four-dimensional Lorentzian Walker manifolds. Also, we show that which of them are gradient vector fields and Killing vector fields.
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A Nobel Variation of 16th-Order Iterative Scheme for Models in Blood Stream, Chemical Reactor, and Its Dynamics Lobachevskii J. Math. Pub Date : 2024-03-25 Saima Akram, Hareem Khalid, Tulkin Rasulov, Maira Khalid, Mutti-Ur Rehman
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On a Hadamard–Haar Discrete Wavelet Transform and Its Inversion Lobachevskii J. Math. Pub Date : 2024-03-25 Nassar H. S. Haidar
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Boundary Value Problems for a Mixed Equation of Parabolic-Hyperbolic Type of the Third Order Lobachevskii J. Math. Pub Date : 2024-03-25 Yu. P. Apakov, A. A. Sopuev
Abstract In this article, the existence and uniqueness of solution of the conjugation problem in a rectangular domain for a third-order partial differential equation is proved, when the characteristic equation has 3 multiple roots for \(y>0\), and it has 1 simple and 2 multiple roots for \(y<0\). Using the Green’s functions and the method of integral equations, the solution of the problem is equivalently
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On o-Stable Expansions of $$\boldsymbol{(\mathbb{Z},<,+)}$$ Lobachevskii J. Math. Pub Date : 2024-03-25 V. V. Verbovskiy, A. D. Yershigeshova
Abstract Roughly speaking, an ordered structure \((M,<,\dots)\) is o-stable if any cut in \(M\) has a few extensions up to complete 1-types over \(M\). A theory is o-stable if all its models are. O-stability is a generalization of (weak) o-minimality and quasi-o-minimality by using the notion of a stable theory. In the paper, we prove that no proper (essential) expansion of the ordered group of integers
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Small Dual-ADS Modules, Small ADS $${}^{\mathbf{\#}}$$ and Small ADS* Modules Lobachevskii J. Math. Pub Date : 2024-03-25 Adel Abyzov, Bui Tien Dat, Truong Cong Quynh
Abstract A right module \(M\) over a ring \(R\) is called small dual-ADS, if for each decomposition \(M=A\oplus B,\) then \(A\) and \(B\) are mutually small projective. Small dual-ADS modules are the dual analogue of LADS modules, a class of modules recently studied. In this article, we study several properties of these modules. It is shown that a module \(M\) is small dual-ADS if and only if for every
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Impact of Parallel Code Optimization on Computer Power Consumption Lobachevskii J. Math. Pub Date : 2024-03-25 E. A. Kiselev, P. N. Telegin, A. V. Baranov
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An Approach to Assessing the Effectiveness of Radiation Conformal Multi-Element Structures with Chiral Filling Lobachevskii J. Math. Pub Date : 2024-03-14 A. L. Buzov, M. A. Buzova, D. S. Klyuev, A. M. Neshcheret, Yu. V. Sokolova, S. V. Morozov
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Bivariate Sushila Distribution Based on Copulas: Properties, Simulations, and Applications Lobachevskii J. Math. Pub Date : 2024-03-14 Sirinapa Aryuyuen, Wattana Panphut, Chookait Pudprommarat
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On Geometric Form of a Hahn–Banach Theorem’s Version for Idempotent Probability Measures Lobachevskii J. Math. Pub Date : 2024-03-14 A. O. Tagaymurotov, A. A. Zaitov
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Compression Pulse Propagation in Fractured Porous Medium Lobachevskii J. Math. Pub Date : 2024-03-14 A. A. Gubaidullin, O. Yu. Boldyreva, D. N. Dudko
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The Sine Modified Power-Generated Family of Distributions with Application to Practical Data and Ruin Probability Lobachevskii J. Math. Pub Date : 2024-03-14 Christophe Chesneau, Hassan S. Bakouch, Kadir Karakaya, Abouzar Bazyari
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Analysis of a Dependent Perturbed Renewal Risk Model with Heavy-tailed Distributions Lobachevskii J. Math. Pub Date : 2024-03-14 Abouzar Bazyari
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Approximation Results by Statistical Convergence Based on a Power Series in Modular Spaces Lobachevskii J. Math. Pub Date : 2024-03-14 E. Tas, T. Yurdakadim
Abstract In this study, we present some approximation results in modular spaces for positive linear operators with the use of \(P\)-statistical convergence which is recently added to literature by combining statistical convergence and power series. As an application, we provide an example which shows that our theorems are efficient to use since \(P\)-statistical convergence assigns a limit to a divergent
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Sequential d-Posterior Procedure for Selecting the Most Probable Multinomial Outcome Lobachevskii J. Math. Pub Date : 2024-03-14 I. A. Kareev
Abstract A selection problem for finding the most probable outcome of a multinomial distribution is considered. We present a sequential procedure for solving a d-posterior variation of the problem. For the procedure the convergence and sample size properties are investigated. The paper is concluded with numerical illustrations of the actually achievable d-posterior reliability, average sample size
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Probability of Net Superiority for Comparing Two Groups or Group Means Lobachevskii J. Math. Pub Date : 2024-03-14 Hening Huang
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Investigation of Light Scattering by Plasmonic Core-Shell Nanoparticles via the Discrete Sources Method Accounting for the Surface Quantum Effect Lobachevskii J. Math. Pub Date : 2024-03-14 Yu. A. Eremin, V. V. Lopushenko
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Regularity and Optimality Necessary Conditions for System of G-Stochastic Differential Equations Lobachevskii J. Math. Pub Date : 2024-03-14 H. Ben Gherbal, A. Redjil, Z. Arab
Abstract In the current paper, we deal with a system of G-stochastic differential equations (G-SDEs in short) driven by G-Brownian motion. Under some assumptions on the coefficients, we prove the temporal Hölder regularity of the solution. Moreover, we establish the Pontryagin’s maximum principle for optimal control of such system. An example is given to support the effectiveness of our main results
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Self-Sufficient Algorithm of the Method of Surface Integral Equations in the Problems of Electromagnetic Scattering by Magneto-dielectric Cylinders Lobachevskii J. Math. Pub Date : 2024-03-14 D. A. Borisov, S. P. Skobelev
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Evolution of the Surface Computational Mesh in the Ice Accretion Process Lobachevskii J. Math. Pub Date : 2024-03-14 A. O. Meshcheryakov, A. A. Rybakov
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Nonisothermal Fluid Filtration to a Vertical Well in Naturally Fractured Reservoir Lobachevskii J. Math. Pub Date : 2024-01-28 M. N. Shamsiev, M. Kh. Khairullin, P. E. Morozov, V. R. Gadil’shina, A. I. Abdullin, A. V. Nasybullin
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Non-Newtonian Flow on Homogeneous-Heterogeneous Pore-Scale Reactive Transport: A Computational Analysis Lobachevskii J. Math. Pub Date : 2024-01-28 V. V. Grigoriev, W. Xie
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Lattice Boltzmann Simulations of the Dynamic Adsorption of Gas in Porous Media: Effect of Grain Size Distribution Lobachevskii J. Math. Pub Date : 2024-01-28 T. R. Zakirov, M. G. Khramchenkov, A. N. Kolchugin, A. A. Galeev
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Optimization of the Movement of a Cylindrical Vibration-Driven Robot in a Viscous Fluid, Induced by Pendulum Oscillations of the Internal Mass Lobachevskii J. Math. Pub Date : 2024-01-28 A. G. Egorov, A. N. Nuriev, V. D. Anisimov
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Online Coupled Generalized Multiscale Finite Element Method for the Poroelasticity Problem in Three-Dimensional Media Lobachevskii J. Math. Pub Date : 2024-01-28 A. A. Tyrylgin, J. Huang
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An Online Generalized Multiscale Finite Element Method for Dual-continuum Unsaturated Filtration Problem in Domains with Rough Boundaries Lobachevskii J. Math. Pub Date : 2024-01-28 D. A. Spiridonov, J. Huang
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Partial Learning Using Partially Explicit Discretization for Heterogeneous Transport Problem Simulation Lobachevskii J. Math. Pub Date : 2024-01-28 V. N. Alekseev, U. S. Kalachikova, Y. Yang
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Integration of a Nonlinear Hirota Type Equation with Finite Density in the Class of Periodic Functions Lobachevskii J. Math. Pub Date : 2024-01-28 A. Khasanov, R. Eshbekov, Kh. Normurodov
Abstract In this paper, the inverse spectral problem method is used to integrate a nonlinear Hirota-type equation with a finite density in the class of periodic functions. The evolution of the spectral data of the periodic Dirac operator is introduced and the coefficient of the Dirac operator is a solution of the nonlinear Hirota equation with a finite density. The solvability of the Cauchy problem
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An Exponential-Trigonometric Optimal Interpolation Formula Lobachevskii J. Math. Pub Date : 2024-01-28 Kh. M. Shadimetov, A. K. Boltaev
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Criteria for Approximative Properties of Systems of Sines and Cosines in Grand Lebesgue Space Lobachevskii J. Math. Pub Date : 2024-01-28 T. Hagverdi
Abstract In this article the trigonometric systems of sine \(\sin\left(n-\alpha\right)t\), \(n=1,2,...\) and cosine \({\cos}\left(n-\alpha\right)t\), \(n=0,1,2,...\) are considered in the grand Lebesgue space \(L_{p)}(0,\pi)\), where \(\alpha\) is a real parameter. The basis properties: criteria for minimality, completeness and basicity of these trigonometric systems with respect to the parameter \(\alpha\)
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A Problem with Shift for Mixed-Type Equation in Domain, the Elliptical Part of Which Is a Horizontal Strip Lobachevskii J. Math. Pub Date : 2024-01-28 R. T. Zunnunov
Abstract In this article, the issue of the unique solvability of a problem with shift in an unbounded domain is investigated; the elliptical part of the domain is a horizontal strip. The uniqueness of the theorem is proven by the method of energy integrals under constraints of unequal type on known functions and different orders of fractional differentiation operators in the boundary condition. Problem
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A Diffusive Leslie–Gower Type Predator–Prey Model with Two Different Free Boundaries Lobachevskii J. Math. Pub Date : 2024-01-28 A. N. Elmurodov, A. I. Sotvoldiyev
Abstract In this paper, we study the diffusive mutualist model with advection and different free boundaries in one space dimension. These two free boundaries may intersect each other as time evolves and can be used to describe the spreading of invasive and native species directly. Methods for obtaining a priori estimates in the norms of Hölder spaces for the solution are proposed. On the basis of these
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Arithmetic and Combinatorics of Recurrent Sequences Lobachevskii J. Math. Pub Date : 2024-01-28 R. V. Urazbakhtin
Abstract The arithmetic properties of integer sequences responsible for the number of tiling rings divided into a finite number of identical cells using two polyominoes are investigated. Recurrent sequences associated with Pascal’s triangle are also studied.
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On the Maximum and Minimum Areas of the Necklace Lobachevskii J. Math. Pub Date : 2024-01-28 R. R. Gazizov
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Polubarinova–Galin Equation for Hele-Shaw Flows with Two Free Boundaries Lobachevskii J. Math. Pub Date : 2024-01-28 M. M. Alimov
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Inverse Problems for Kelvin–Voigt System with Memory: Global Existence and Uniqueness Lobachevskii J. Math. Pub Date : 2024-01-28 Kh. Khompysh, A. G. Shakir
Abstract This paper deals with the global unique solvability of two inverse problems for Kelvin–Voigt system with memory that governs the flow of incompressible non-Newtonian fluids with relaxation and elastic properties. Inverse problems that study here, consist of determining a time dependent intensity of the density of external forces, along with a velocity and a pressure of fluids. As additional
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The Equations of the Darcy–Brinkman Flow: the Lie Symmetry Classification, Conservation Laws, and Traveling Wave Solutions Lobachevskii J. Math. Pub Date : 2023-12-11 I. S. Krasil’shchik, O. I. Morozov
Abstract We consider the differential equations that describe the Darcy–Brinkman flow. We provide the Lie symmetry classification of this system, construct conservation laws and study the system that describes the traveling wave solutions. We show that the integration of the last system is reducible to the Abel ordinary differential equation and indicate a case when this ordinary differential equation
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Contact Transformations in Theory of Frontal Oil Displacement Lobachevskii J. Math. Pub Date : 2023-12-11 S. S. Mukhina
Abstract The paper deals with Barenblat’s model of non-stationary two-phase filtration of oil and water with active reagents. This model describes frontal It is described by the first order hyperbolic system of two nonlinear partial differential equations. We show that this system is equivalent to the symplectic Monge–Ampère equation. In the case of carbonized water this equation is contact equivalent
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A Lax Representation of the Charney–Obukhov Equation for the Ocean Lobachevskii J. Math. Pub Date : 2023-12-11 O. I. Morozov
Abstract We find a Lax representation of the 4D Charney–Obukhov equation for the ocean in the \(\beta\)-plane approximation. We prove that a parameter involved in the Lax representation is non-removable. Then we derive a special Bäcklund transformation for the equation under the study.
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Method of Volume Singular Equations for Solving a Nonlinear Problem of Diffraction in a Semi-Infinite Rectangular Waveguide Lobachevskii J. Math. Pub Date : 2023-12-11 A. O. Lapich, M. Yu. Medvedik
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Spectral Characteristics of the Integral Operator of the Internal Problem of Electrodynamics for Cylindrical Spiral Structure Lobachevskii J. Math. Pub Date : 2023-12-11 D. P. Tabakov, A. G. Majorov, R. M. Valiullin, D. S. Klyuev
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Comparison of Approximate and Numerical Methods for Solving the Homogeneous Dirichlet Problem for the Helmholtz Operator in a Two-Dimensional Domain Lobachevskii J. Math. Pub Date : 2023-12-11 E. G. Apushkinskiy, V. A. Kozhevnikov, A. V. Biryukov
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Perturbations of Differential Equations Retaining Conserved Quantities Lobachevskii J. Math. Pub Date : 2023-12-11 A. Samokhin
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On the Application of Mosaic-Skeleton Approximations of Matrices in Electrodynamics Problems with Impedance Boundary Conditions Lobachevskii J. Math. Pub Date : 2023-12-11 A. V. Setukha, S. L. Stavtsev
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Integral Equations of Coordinate Diffraction Problems of Elastic Waves in Stratified Media Lobachevskii J. Math. Pub Date : 2023-12-11 I. E. Pleshchinskaya, N. B. Pleshchinskii, K. N. Stekhina
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The Exponentiated Additive Teissier-Exponential Distribution Lobachevskii J. Math. Pub Date : 2023-12-11 V. P. Jha, V. Kumaran
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Generalized Ratio-Cum-Exponential-Log Ratio Type Estimators of Population Mean under Simple Random Sampling Scheme Lobachevskii J. Math. Pub Date : 2023-12-11 Subhash Kumar Yadav, Diksha Arya, Gajendra K. Vishwakarma, Mukesh Kumar Verma
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The Method of Integral Variational Relations in the Problem of Eigenwaves of a Plane Dielectric Layer Coated with Graphene Lobachevskii J. Math. Pub Date : 2023-12-11 Yu. G. Smirnov, E. G. Smolkin
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Scaling Invariance of the $$\boldsymbol{k[S]}$$ -Hierarchy and Its Strict Version Lobachevskii J. Math. Pub Date : 2023-12-11 G. F. Helminck, J. A. Weenink
Abstract Let \(LT_{\mathbb{N}}(R)\) denote the algebra of \(\mathbb{N}\times\mathbb{N}\)-matrices with coefficients from the commutative \(k\)-algebra \(R\), \(k=\mathbb{R}\) or \(\mathbb{C}\), that possess only a finite number of nonzero diagonals above the central diagonal. In a previous paper we discussed integrable deformations inside \(LT_{\mathbb{N}}(R)\) of various commutative subalgebras of
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Critical Phenomena of Massieu–Plank Potential for Gas Mixtures Described by the Beattie–Bridgeman Equations of State Lobachevskii J. Math. Pub Date : 2023-12-11 I. A. Galyaev, M. I. Kostiuchek, A. V. Batov, A. M. Salnikov