Results 31 to 40 of about 539 (137)
Karpatsʹkì Matematičnì Publìkacìï, 2023 The solution of the investigated problem with an unknown coefficient in the equation was constructed by using the method of separation of variables. The properties of the induced spectral problem for the second-order differential equation with involution
Ya.O. Baranetskij +2 more
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Convergence of Hermite expansions in modulation spaces
Bulletin of the London Mathematical Society, Volume 58, Issue 8, August 2026.Abstract The aim of this paper is to give an elementary proof that the Hermite expansion of a function f$f$ in the modulation space Mp(R)$M^p({\mathbb {R}})$ converges to f$f$ in Mp(R)$M^p({\mathbb {R}})$ when 1
Philippe Jaming, Michael Speckbacher
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Operator Characterizations and Some Properties of g-Frames on Hilbert Spaces
Journal of Function Spaces and Applications, 2013 Given the g-orthonormal basis for Hilbert space H, we characterize the g-frames, normalized tight g-frames, and g-Riesz bases in terms of the g-preframe operators.
Xunxiang Guo
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Low eigenvalues of the p$p$–Laplacian in general open sets
Journal of the London Mathematical Society, Volume 114, Issue 2, August 2026.Abstract We consider the minmax Ljusternik–Schnirelmann levels of the constrained p$p$–Dirichlet integral on a general open set of the Euclidean space. We show that, whenever one of these levels lies below the threshold given by the Lp$L^p$ Poincaré constant “at infinity,” it actually defines an eigenvalue of the Dirichlet p$p$–Laplacian. We also prove
Lorenzo Brasco +2 more
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Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2014 We made the comparison study and characterize the spectral properties of differential operators induced by the Dirichlet problem for the hyperbolic system without the lowest terms of the form $$ \cfrac{\partial^2{u^1}}{\partial{t}^2}+\cfrac{\partial^2{u ...
Olesya V Alexeeva +2 more
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Finite Element Approximation for a Reformulation of a 3D Fluid–2D Plate Interaction System
Numerical Methods for Partial Differential Equations, Volume 42, Issue 4, July 2026.ABSTRACT We study a finite element approximation of a coupled fluid‐structure interaction consisting of a three‐dimensional incompressible viscous fluid governed by the unsteady Stokes equations and a two‐dimensional elastic plate. To avoid the use of H2−$$ {H}^2- $$conforming or nonconforming ℙ2$$ {\mathbb{P}}_2 $$‐Morley plate elements, the fourth ...
Lander Besabe, Hyesuk Lee
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The Canadian Journal of Chemical Engineering, Volume 104, Issue 6, Page 3018-3037, June 2026.Abstract We develop a delay‐aware estimation and control framework for a non‐isothermal axial dispersion tubular reactor modelled as a coupled parabolic‐hyperbolic PDE system with recycle‐induced state delay. The infinite‐dimensional dynamics are preserved without spatial discretization by representing the delay as a transport PDE and adopting a late ...
Behrad Moadeli, Stevan Dubljevic
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Қарағанды университетінің хабаршысы. Математика сериясыIn this paper, the inverse problem for a fourth-order parabolic equation with a variable complex-valued coefficient is studied by the method of separation of variables.
A.B. Imanbetova +2 more
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Spectral Properties of Non-Self-Adjoint Perturbations for a Spectral Problem with Involution
Abstract and Applied Analysis, 2012 Full description of Riesz basis property for eigenfunctions of boundary value problems for first order differential equations with involutions is given.
Asylzat A. Kopzhassarova +2 more
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ON THE INVERSE PROBLEM OF THE BITSADZE–SAMARSKII TYPE FOR A FRACTIONAL PARABOLIC EQUATION
Проблемы анализа, 2023 In this paper, the inverse problem of the Bitsadze–Samarsky type is studied for a fractional order equation with a Hadamard–Caputo fractional differentiation operator. The problem is solved using the spectral method.
R. R. Ashurov +2 more
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