Results 61 to 70 of about 5,416,832 (202)
Boundary Value Problems, 2020 In this paper we consider singular Sturm–Liouville problems with eigenparameter dependent boundary conditions and two singular endpoints. The spectrum of such problems can be approximated by those of the inherited restriction operators constructed.
Maozhu Zhang, Kun Li, Hongxiang Song
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Scattering theory for difference equations with operator coefficients
Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.Abstract We investigate a class of second‐order difference equations featuring operator‐valued coefficients with the aim of approaching problems of stationary scattering theory. We focus on various compact perturbations of the discrete Laplacian given in a Hilbert space of bi‐infinite square‐summable sequences with entries from a fixed Hilbert space ...
David Sher +3 more
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Spectral Parameter Power Series Representation for Regular Solutions of the Radial Dirac System
Mathematical Methods in the Applied Sciences, Volume 49, Issue 3, Page 2098-2113, February 2026.ABSTRACT A spectral parameter power series (SPPS) representation for the regular solution of the radial Dirac system with complex coefficients is obtained, as well as a SPPS representation for the (entire) characteristic function of the corresponding spectral problem on a finite interval. Based on the SPPS representation, a numerical method for solving
Emmanuel Roque, Sergii M. Torba
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Inequalities among eigenvalues of Sturm–Liouville problems
Journal of Inequalities and Applications, 1999 There are well-known inequalities among the eigenvalues of Sturm–Liouville problems with periodic, semi-periodic, Dirichlet and Neumann boundary conditions.
Kong Q, Wu H, Zettl A, Eastham MSP
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Maxwell Fronts in the Discrete Nonlinear Schrödinger Equations With Competing Nonlinearities
Studies in Applied Mathematics, Volume 156, Issue 2, February 2026.ABSTRACT In discrete nonlinear systems, the study of nonlinear waves has revealed intriguing phenomena in various fields such as nonlinear optics, biophysics, and condensed matter physics. Discrete nonlinear Schrödinger (DNLS) equations are often employed to model these dynamics, particularly in the context of Bose–Einstein condensates and optical ...
Farrell Theodore Adriano, Hadi Susanto
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Controllability and Observability of Nonautonomous Riesz-Spectral Systems
Abstract and Applied Analysis, 2018 There are many industrial and biological reaction diffusion systems which involve the time-varying features where certain parameters of the system change during the process.
Sutrima Sutrima +2 more
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Mathematical Methods in the Applied Sciences, Volume 49, Issue 2, Page 521-530, 30 January 2026.ABSTRACT This paper investigates the generalized Hyers–Ulam stability of the Laplace equation subject to Neumann boundary conditions in the upper half‐space. Traditionally, Hyers–Ulam stability problems for differential equations are analyzed by examining the system's error, particularly in relation to a forcing term.
Dongseung Kang +2 more
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Space versus energy oscillations of Prufer phases for matrix Sturm-Liouville and Jacobi operators
Electronic Journal of Differential Equations, 2020 This note considers Sturm oscillation theory for regular matrix Sturm-Liouville operators on finite intervals and for matrix Jacobi operators. The number of space oscillations of the eigenvalues of the matrix Prufer phases at a given energy, defined ...
Hermann Schulz-Baldes, Liam Urban
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A Spectral Theory for a λ-Rational Sturm–Liouville Problem
Journal of Differential Equations, 2001 Linearizing the Navier-Stokes equations with a magnetic field for a velocity field of a plasma with axial symmetry, the axial and the azimuthal components of the velocity can be eliminated at the expense of a rational dependence on the eigenvalue parameter in the equation for the remaining velocity component. Corresponding eigenvalue problems such as \[
Adamjan, V., Langer, Heinz, Langer, M.
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IET Radar, Sonar &Navigation, Volume 20, Issue 1, January/December 2026.This study quantifies the impact of internal solitary wave–induced magnetic disturbances on underwater geomagnetic navigation performance in the South China Sea. A physics‐guided volumetric reconstruction framework integrating SWOT altimetry is developed to recover spatiotemporal subsurface magnetic fields.
Zhikuan Pan +6 more
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