Contemporary Mathematics, Volume 3 Issue 4 (2022), 386-561 < Previous vol / issue Next vol/issue >

This issue is in progress but contains articles that are final and fully citable.

Geodesic Triangles in H² with Short Sides

by Gitik Rita

Abstract: We prove that if M is an orientable hyperbolic surface without boundary (possibly compact, possibly with infinitely generated fundamental group) and γ is a closed geodesic in M then any side of any...

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Generalization of Tail Inequalities for Random Variables in the Martingale Theory

by Formica Maria Rosaria,Ostrovsky Eugeny,Sirota Leonid

Abstract: We generalize the tail Doob's inequality, concerning two non-negative random variables, arising in the martingale theory, in three directions: on the more general source data, on the random variables ...

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On the Classical Solutions for the Kuramoto-Sivashinsky Equation with Ehrilch-Schwoebel Effects

by Coclite Giuseppe Maria ,Di Ruvo Lorenzo

Abstract: The Kuramoto-Sivashinsky equation with Ehrilch-Schwoebel effects models the evolution of surface morphology during Molecular Beam Epitaxy growth, provoked by an interplay between deposition of atoms o...

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The Existence of Solution to Fractional Boundary Value Problem with Riemann-Liouville Type History-State-Based Variable-Order Derivative

by Zhang Shuqin,Wang Jie

Abstract: The paper is devoted to studying the solutions of boundary value problem for nonlinear fractional differential equation with Riemann-Liouville type history-state-based variable-order derivative. Using...

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Adaptive Identification of System with Bouc-Wen Hysteresis Modifications

by Karabutov Nikolay

Abstract: The adaptive identification method developed to evaluate the parameters of the Bouc-Wen hysteresis (BWH). The adaptive approach based on the use of adaptive observer. We synthesize adaptive identifica...

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Algebraic Method for Approximate Solution of Scattering of Surface Waves by Thin Vertical Barrier Over a Stepped Bottom Topography

by Kumar Naveen,Goyal Deepali,Martha S. C.

Abstract: A study on interaction of surface water waves by thin vertical rigid barrier over a step type bottom topography is analysed. The associated mixed boundary value problem is solved using the eigenfuncti...

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A Jordan-Schur Algorithm for Solving Sylvester and Lyapunov Matrix Equations

by Petkov P. H.

Abstract: This paper presents a version of the Bartels-Stewart algorithm for solving the Sylvester and Lyapunov equations that utilizes the Jordan-Schur form of the equation matrices. The Jordan-Schur form is a...

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Freudenthal Suspension Theorem And James-Hopf Invariant of Spheres

by Golasiński Marek

Abstract: This paper relates more precisely the image of the suspension map Σ:π2n+k(Sn) → π2n+k+1(Sn+1) with the kernel of James-Hopf invariant h2:π2n+k+1(Sn+1) → π2n+k+1(S2n+1) for k ≤ 9....

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Moving Averages that Preserve the Monotonicity of Quotients

by Estrada Ricardo

Abstract: There are operators that have the property that when applied to both the numerator and the denominator of a monotonic quotient of functions or sequences produce another monotonic quotient. Such operat...

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