Results 11 to 20 of about 836 (186)

Uniqueness Results of Semilinear Parabolic Equations in Infinite-Dimensional Hilbert Spaces

Mathematics
This paper is devoted to the uniqueness of solutions for a class of nonhomogeneous stationary partial differential equations related to Hamilton–Jacobi-type equations in infinite-dimensional Hilbert spaces.
Carlo Bianca, Christian Dogbe
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Regional Enlarged Observability of Fractional Differential Equations with Riemann—Liouville Time Derivatives

Axioms, 2018
We introduce the concept of regional enlarged observability for fractional evolution differential equations involving Riemann⁻Liouville derivatives. The Hilbert Uniqueness Method (HUM) is used to reconstruct the initial state between two prescribed
Hayat Zouiten, Ali Boutoulout, Delfim F. M. Torres   +2 more
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Approximate Controllability of a 3D Nonlinear Stochastic Wave Equation

Journal of Applied Mathematics, 2014
We study the well-posedness of a 3D nonlinear stochastic wave equation which derives from the Maxwell system by the Galerkin method. Then we study the approximate controllability of this system by the Hilbert uniqueness method.
Peng Gao
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The behavior of solutions of non-linear differential equations in Hilbert space. I

International Journal of Mathematics and Mathematical Sciences, 1988
This paper deals with the behavior of solutions of ordinary differential equations in a Hilbert Space. Under certain conditions, we obtain lower estimates or upper estimates (or both) for the norm of solutions of two kinds of equations.
Vladimir Schuchman
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Using a Divergence Regularization Method to Solve an Ill-Posed Cauchy Problem for the Helmholtz Equation

Abstract and Applied Analysis, 2022
The ill-posed Helmholtz equation with inhomogeneous boundary deflection in a Hilbert space is regularized using the divergence regularization method (DRM).
Benedict Barnes, Anthony Y. Aidoo, Joseph Ackora-Prah   +2 more
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Observability and uniqueness theorem for a coupled hyperbolic system

International Journal of Mathematics and Mathematical Sciences, 2000
We deal with the inverse inequality for a coupled hyperbolic system with dissipation. The inverse inequality is an indispensable inequality that appears in the Hilbert Uniqueness Method (HUM), to establish equivalence of norms which guarantees uniqueness
Boris V. Kapitonov, Joel S. Souza
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A source inverse problem for the pseudo–parabolic equation with the fractional Sturm–Liouville operator

Қарағанды университетінің хабаршысы. Математика сериясы, 2020
A class of inverse problems for restoring the right-hand side of the pseudo-parabolic equation with one fractional Sturm–Liouville operator is considered.
D. Serikbaev, N. Tokmagambetov
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Inverse Sturm–Liouville Problem with Spectral Parameter in the Boundary Conditions

Mathematics, 2023
In this paper, for the first time, we study the inverse Sturm–Liouville problem with polynomials of the spectral parameter in the first boundary condition and with entire analytic functions in the second one.
Natalia P. Bondarenko, Egor E. Chitorkin
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The Regional Enlarged Observability for Hilfer Fractional Differential Equations

Axioms, 2023
In this paper, we investigate the concept of regional enlarged observability (ReEnOb) for fractional differential equations (FDEs) with the Hilfer derivative. To proceed this, we develop an approach based on the Hilbert uniqueness method (HUM). We mainly
Abu Bakr Elbukhari, Zhenbin Fan, Gang Li
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Regional Controllability and Minimum Energy Control of Delayed Caputo Fractional-Order Linear Systems

Mathematics, 2022
We study the regional controllability problem for delayed fractional control systems through the use of the standard Caputo derivative. First, we recall several fundamental results and introduce the family of fractional-order systems under consideration.
Touria Karite, Adil Khazari, Delfim F. M. Torres   +2 more
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