Abstract:
We consider the ill-posed problem of localizing (finding the position) the discontinuity lines of a function of two variables, provided that the function of two variables is smooth outside of the discontinuity lines, and at each point on the line has a discontinuity of the first kind. There is a uniform grid with the step ττ. It is assumed that we know the averages on the square τ×τ of the perturbed function at each node of the grid. The perturbed function approximates the exact one in space L2(R2). The perturbation level δ is known. Earlier, the authors investigated (obtained accuracy estimates) the global discrete regularizing algorithms for approximating a set of discontinuity lines of a noisy function. However, stringent smoothness conditions were superimposed on the discontinuity line. The main result of this paper is the improvement of localizing the accuracy estimation methods, which allows replacing the smoothness requirement with a weaker Lipschitz condition. Also, the conditions of separability are formulated in a more general form, as compared to previous studies. In particular, it is established that the proposed algorithm make it possible to obtain the localization accuracy of the order O(δ). Also, estimates of other important parameters characterizing the localization algorithm are given.
Citation:
A. L. Ageev, T. V. Antonova, “New accuracy estimates for methods for localizing
discontinuity lines of a noisy function”, Sib. Zh. Vychisl. Mat., 23:4 (2020), 351–364; Num. Anal. Appl., 13:4 (2020), 293–305
\Bibitem{AgeAnt20}
\by A.~L.~Ageev, T.~V.~Antonova
\paper New accuracy estimates for methods for localizing
discontinuity lines of a noisy function
\jour Sib. Zh. Vychisl. Mat.
\yr 2020
\vol 23
\issue 4
\pages 351--364
\mathnet{http://mi.mathnet.ru/sjvm753}
\crossref{https://doi.org/10.15372/SJNM20200401}
\transl
\jour Num. Anal. Appl.
\yr 2020
\vol 13
\issue 4
\pages 293--305
\crossref{https://doi.org/10.1134/S1995423920040011}
\isi{https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=Publons&SrcAuth=Publons_CEL&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=000600885900001}
Linking options:
https://www.mathnet.ru/eng/sjvm753
https://www.mathnet.ru/eng/sjvm/v23/i4/p351
This publication is cited in the following 3 articles:
A. L. Ageev, T. V. Antonova, “A Study of New Methods for Localizing Discontinuity Lines on Extended Correctness Classes”, Proc. Steklov Inst. Math. (Suppl.), 323, suppl. 1 (2023), S19–S31
A. L. Ageev, T. V. Antonova, “O lokalizatsii fraktalnykh linii razryva po zashumlennym dannym”, Izv. vuzov. Matem., 2023, no. 9, 27–44
A. L. Ageev, T. V. Antonova, “On the Localization of Fractal Lines of Discontinuity from Noisy Data”, Russ Math., 67:9 (2023), 23