Abstract
We study singularly perturbed problems in the presence of spectral singularities of the limit operator using S.A. Lomov’s regularization method. In particular, a regularized asymptotic solution is constructed for a singularly perturbed inhomogeneous mixed problem on the half-line for a parabolic equation with a strong turning point of the limit operator. Based on the idea of asymptotic integration of problems with unstable spectrum, it is shown how regularizing functions and additional regularizing operators should be introduced, the formalism of the regularization method for this type of singularity is described in detail, this algorithm is justified, and an asymptotic solution of any order in a small parameter is constructed.
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Funding
The results by A.G. Eliseev (statement of the problem and the derivation of the equations for regularizing functions, the singular operators for regularizing the right-hand sides of iterative problems, and the boundary operator for describing the boundary layer in the vicinity of the point \(x=0 \)) were obtained with the support of the Ministry of Science and Higher Education of the Russian Federation as part of the state order, project no. FSWF-2023-0012.
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Translated by V. Potapchouck
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Eliseev, A.G., Ratnikova, T.A. & Shaposhnikova, D.A. Solution of a Singularly Perturbed Mixed Problem on the Half-Line for a Parabolic Equation with a Strong Turning Point of the Limit Operator. Diff Equat 59, 1032–1049 (2023). https://doi.org/10.1134/S0012266123080037
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DOI: https://doi.org/10.1134/S0012266123080037