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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="other" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Yugra State University Bulletin</journal-id><journal-title-group><journal-title xml:lang="en">Yugra State University Bulletin</journal-title><trans-title-group xml:lang="ru"><trans-title>Вестник Югорского государственного университета</trans-title></trans-title-group></journal-title-group><issn publication-format="print">1816-9228</issn><issn publication-format="electronic">2078-9114</issn><publisher><publisher-name xml:lang="en">Yugra State University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">688837</article-id><article-id pub-id-type="doi">10.18822/byusu20250354-59</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Mathematical modeling and information technology</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Математическое моделирование и информационные технологии</subject></subj-group><subj-group subj-group-type="article-type"><subject>Unknown</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Determination of the absorption coefficient from discrete data</article-title><trans-title-group xml:lang="ru"><trans-title>Определение коэффициента поглощения по точечным данным</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Tukmacheva</surname><given-names>Julia A.</given-names></name><name xml:lang="ru"><surname>Тукмачева</surname><given-names>Юлия Андреевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Postgraduate student, Engineering School of Digital Technologies</p></bio><bio xml:lang="ru"><p>аспирант 2 года обучения направления, «Математическое моделирование, численные методы и комплексы программ» Инженерной школы цифровых технологий</p></bio><email>y_tukmacheva@ugrasu.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Pyatkov</surname><given-names>Sergey G.</given-names></name><name xml:lang="ru"><surname>Пятков</surname><given-names>Сергей Григорьевич</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><email>s_pyatkov@ugrasu.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Yugra State University</institution></aff><aff><institution xml:lang="ru">Югорский государственный университет</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-09-30" publication-format="electronic"><day>30</day><month>09</month><year>2025</year></pub-date><volume>21</volume><issue>3</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>54</fpage><lpage>59</lpage><history><date date-type="received" iso-8601-date="2025-08-07"><day>07</day><month>08</month><year>2025</year></date><date date-type="accepted" iso-8601-date="2025-08-28"><day>28</day><month>08</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Yugra State University</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Югорский государственный университет</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Yugra State University</copyright-holder><copyright-holder xml:lang="ru">Югорский государственный университет</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-sa/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://vestnikugrasu.org/byusu/article/view/688837">https://vestnikugrasu.org/byusu/article/view/688837</self-uri><abstract xml:lang="en"><p>Subject of research: inverse problems concerning the determination of an absorption coefficient in a parabolic equation from discrete (pointwise) data.</p> <p>Purpose of research: establishing the well-posedness of the problem of determining the lower-order coefficient in a parabolic equation from pointwise overdetermination conditions; proving the existence and uniqueness of a solution in Sobolev spaces.</p> <p>Research methods: a priori estimates, Schauder’s fixed-point theorem, and the theory of parabolic operators.</p> <p>Objects of research: parabolic equations with an unknown absorption coefficient represented as a linear combination of known functions with unknown coefficients.</p> <p>Research findings: a theorem on the existence and uniqueness of solutions in Sobolev spaces is proven, and a priori estimates are derived. The method is constructive and can serve as a foundation for developing a numerical algorithm for the approximate solution of the inverse problem.</p></abstract><trans-abstract xml:lang="ru"><p>Цель исследования: установление корректности задачи определения младшего коэффициента в параболическом уравнении по точечным условиям переопределения, доказательство существования и единственности решения в пространствах Соболева.</p> <p>Методы исследования: априорные оценки, теорема Шаудера, теория параболических операторов.</p> <p>Объекты исследования: параболические уравнения с неизвестным коэффициентом поглощения, представляемым в виде линейной комбинации известных функций с неизвестными коэффициентами.</p> <p>Основные результаты исследования: доказана теорема существования и единственности решений в пространствах Соболева, получены априорные оценки. Метод носит конструктивный характер и может служить основой для построения численного алгоритма приближённого решения обратной задачи.</p></trans-abstract><kwd-group xml:lang="en"><kwd>inverse problem</kwd><kwd>absorption parameter</kwd><kwd>parabolic equation</kwd><kwd>heat and mass transfer</kwd><kwd>Sobolev spaces</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>обратная задача</kwd><kwd>коэффициент поглощения</kwd><kwd>параболическое уравнение</kwd><kwd>тепломассоперенос</kwd><kwd>пространство Соболева</kwd></kwd-group><funding-group><funding-statement xml:lang="en">This work was supported by the Russian Science Foundation and the Government of the Khanty-Mansiysk Autonomous Okrug – Yugra (Grant no. 25-11-20026).</funding-statement><funding-statement xml:lang="ru">Работа выполнена при финансовой поддержке Российского научного фонда и Правительства Ханты-Мансийского автономного округа – Югры (грант № 25-11-20026).</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Алифанов, О. М. Обратные задачи сложного теплообмена / О. М. Алифанов, Е. А. Артюхов, А. В. Ненарокомов. – Москва : Янус-К, 2009. – 299 с.</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>Ozisik, M. N. Inverse Heat Transfer / M. N. Ozisik, H. R. B. Orlande. – New York : Taylor &amp; Francis, 2000. – 350 p.</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>Marchuk, G. I. Mathematical Models in Environmental Problems / G. I. Marchuk. – Amsterdam : Elsevier Science Publishers, 1986. – Vol. 16. – 216 p.</mixed-citation></ref><ref id="B4"><label>4.</label><mixed-citation>Prilepko, A. I. Methods for solving inverse problems in Mathematical Physics / A. I. Prilepko, D. G. Orlovsky, I. A. Vasin. – New-York : Marcel Dekker, Inc., 1999. – 744 p.</mixed-citation></ref><ref id="B5"><label>5.</label><mixed-citation>Glagolev, M. V. Determination of gas exchange on the border between ecosystem and atmosphere: inverse modeling / M. V. Glagolev, A. F. Sabrekov // Mathematical Biology and Bioinformatics. – 2012. – Vol. 7, № 1. – P. 81–101.</mixed-citation></ref><ref id="B6"><label>6.</label><mixed-citation>Sabrekov, A. F. Determination of the specific flux of methane from soil using inverse modeling based on conjugate equations / A. F. Sabrekov, M. V. Glagolev, I. E. Terentyeva // Reports of the International Conference «Mathematical Biology and Bioinformatics» / ed. V. D. Lakhno. – Pushchino : IMPB RAS, 2018. – Vol. 7. – P. e94.</mixed-citation></ref><ref id="B7"><label>7.</label><mixed-citation>Assessment of methane emission from measured concentrations in the atmospheric surface layer / A. I. Borodulin, B. D. Desyatkov, G. A. Makhov, S. R. Sarmanaev // Russian meteorology and hydrology. – 1997. – № 1. – P. 49–55.</mixed-citation></ref><ref id="B8"><label>8.</label><mixed-citation>Soil Methanotrophy Model (MeMo v1.0): a process-based model to quantify global uptake of atmospheric methane by soil / F. Murguia-Flores, S. Arndt, A. L. Ganesan [et al.] // Geoscientific Model Development. – 2018. – Vol. 11. – P. 2009–2032.</mixed-citation></ref><ref id="B9"><label>9.</label><mixed-citation>Identification of the methane consumption rate in soils by the inverse problem method / A. F. Sabrekov, M. V. Glagolev, I. E. Terentyeva, S. Yu. Mochenov // Reports of the International Conference «Mathematical Biology and Bioinformatics» / ed. V. D. Lakhno. – Pushchino : IMPB RAS, 2018. – Vol. 7. – P. 951–955.</mixed-citation></ref><ref id="B10"><label>10.</label><mixed-citation>Идентификация скорости потребления метана в почвах методом обратной задачи / А. Ф. Сабреков, М. В. Глаголев, И. Е. Терентьева, С. Ю. Моченов // Материалы VI конференции «Математическое моделирование в экологии». – Пущино, 2019. – С. 179–180.</mixed-citation></ref><ref id="B11"><label>11.</label><mixed-citation>Prather, M. J. Overexplaining or underexplaining methane’s role in climate change / M. J. Prather, C. D. Holmes // Proceedings of the National Academy of Sciences. – 2017. – Vol. 114. – P. 5324–5326.</mixed-citation></ref><ref id="B12"><label>12.</label><mixed-citation>Прилепко, А. И. О разрешимости обратных краевых задач определения коэффициента перед младшей производной в параболическом уравнении / А. И. Прилепко, В. В. Соловьев // Дифференциальные уравнения. – 1987. – Т. 23, № 1. – С. 136–143.</mixed-citation></ref><ref id="B13"><label>13.</label><mixed-citation>Prilepko, A. I. Inverse Source and Coefficient Problems for Elliptic and Parabolic Equations in Holder and Sobolev Spaces / A. I. Prilepko, A. B. Kostin, V. V. Solov’ev // Journal of Mathematical Sciences. – 2019. – Vol. 237, № 3. – P. 576–594.</mixed-citation></ref><ref id="B14"><label>14.</label><mixed-citation>Choulliy, M. Generic well-posedness of an inverse parabolic problem – the Hölder-space approach / M. Choulliy, M. Yamamoto // Inverse Problems. – 1996. – Vol 12. – P. 195–205.</mixed-citation></ref><ref id="B15"><label>15.</label><mixed-citation>Choulliy, M. Inverse problem for a semilinear parabolic equation / M. Choulliy // Inverse Problems. – 1994. – Vol. 10. – P. 1123–1132.</mixed-citation></ref><ref id="B16"><label>16.</label><mixed-citation>Kozhanov, A. I. Parabolic Equations with an Unknown Absorption Coefficient / A. I. Kozhanov // Doklady Mathematics. – 2006. – Vol. 74, № 1. – P. 573–576.</mixed-citation></ref><ref id="B17"><label>17.</label><mixed-citation>Кожанов, А. И. Параболические уравнения с неизвестным коэффициентом поглощения / А. И. Кожанов // Вестник Челябинского государственного университета. Математика. Механика. Информатика. – 2011. – № 13. – С. 5–19.</mixed-citation></ref><ref id="B18"><label>18.</label><mixed-citation>Hao, D. N. A noncharacteristic Cauchy problem for linear parabolic equation and related inverse problems / D. N. Hao // Inverse Problems. – 1994. – Vol. 10. – P. 295–315.</mixed-citation></ref><ref id="B19"><label>19.</label><mixed-citation>Beretta, E. Identifying a space dependent coefficient in a reaction-diffusion equation / E. Beretta // Inverse Problems and Imaging. – 2011. – Vol. 5, № 2. – P. 285–296.</mixed-citation></ref><ref id="B20"><label>20.</label><mixed-citation>Kamynin, V. L. The inverse problem of determining the lower-order coefficient in parabolic equations with integral observation / V. L. Kamynin // Mathematical Notes. – 2013. – Vol. 94, № 2. – P. 205–213.</mixed-citation></ref><ref id="B21"><label>21.</label><mixed-citation>Pyatkov, S. G. Identification of thermophysical parameters in mathematical models of heat and mass transfer / S. G. Pyatkov // Journal of Computational and Engineering Mathematics. – 2022. – Vol. 9, № 2. – P. 52–66.</mixed-citation></ref><ref id="B22"><label>22.</label><mixed-citation>Пятков, С. Г. О некоторых классах линейных обратных задач для параболических систем уравнений / С. Г. Пятков, Е. И. Сафонов // Сибирские электронные известия. – 2014. – Т. 11. – С. 777–799. – URL: http://semr.math.nsc.ru/v11/p777-799.pdf (дата обращения: 15.08.2025).</mixed-citation></ref><ref id="B23"><label>23.</label><mixed-citation>Pyatkov, S. G. Inverse problems of recovering lower-order coefficients from boundary integral data / S. G. Pyatkov, O. A. Soldatov // Axioms. – 2025. – Vol. 14, № 2. – P. 116.</mixed-citation></ref><ref id="B24"><label>24.</label><mixed-citation>Pyatkov, S. Coefficient inverse problems of identification of thermophysical parameters from boundary integral data / S. Pyatkov, T. Pronkina // Journal of Mathematical Sciences. – 2024. – Vol. 282, № 2. – P. 241–252.</mixed-citation></ref><ref id="B25"><label>25.</label><mixed-citation>Вабищевич, П. Н. Вычислительная идентификация младшего коэффициента параболического уравнения / П. Н. Вабищевич, В. И. Васильев // Доклады академии наук. Математика. – 2014. – Т. 455, № 3. – С. 258–260.</mixed-citation></ref><ref id="B26"><label>26.</label><mixed-citation>Hussein, M. S. Simultaneous determination of time-dependent coefficients and heat source / M. S. Hussein, D. Lesnic // International Journal for Computational Methods in Engineering Science and Mechanics. – 2016. – Vol. 17, № 5-6. – P. 401–411.</mixed-citation></ref><ref id="B27"><label>27.</label><mixed-citation>Mamonov, A. V. Point source identification in nonlinear advection-diffusion-reaction systems / A. V. Mamonov, Y-H. R. Tsai // Inverse Problems. – 2013. – Vol. 29, № 3. – P. 1–26.</mixed-citation></ref><ref id="B28"><label>28.</label><mixed-citation>Triebel, H. Interpolation theory. Functional spaces. Differential Operators / H. Triebel. – Berlin : VEB Deutscher Verlag der Wissenschaften, 1978. – 532 p.</mixed-citation></ref><ref id="B29"><label>29.</label><mixed-citation>Ladyzhenskaya, O. A. Linear and Quasilinear Equations of Parabolic Type / O. A. Ladyzhenskaya, N. N. Uraltseva, V. A. Solonnikov. – Providence : American Mathematical Society, 1968. – 648 p.</mixed-citation></ref><ref id="B30"><label>30.</label><mixed-citation>Denk, R. Optimal L_p-L_q-estimates for parabolic boundary value problems with inhomogeneous data / R. Denk, M. Hieber, J. Prüss // Mathematische Zeitschrift. – 2007. Vol. 257, № 1. – P. 193–224.</mixed-citation></ref><ref id="B31"><label>31.</label><mixed-citation>Meyries, M. Maximal regularity with temporal weights for parabolic problems with inhomogeneous boundary conditions / M. Meyries, R. Schnaubert // Mathematische Nachrichten. – 2012. – Vol. 285, № 8-9. – P. 1032–1051.</mixed-citation></ref><ref id="B32"><label>32.</label><mixed-citation>Hummel, F. Elliptic and parabolic boundary value problems in weighted function spaces / F. Hummel, N. Lindemulder // Potential Analysis. – 2022. – Vol. 57. – P. 601–669.</mixed-citation></ref><ref id="B33"><label>33.</label><mixed-citation>Liebermann, G. M. Second order parabollic differential equations / G. M. Liebermann. – Singapure : World Scientific Publishing Co. Pte. Ltd., 2005. – 452 p.</mixed-citation></ref><ref id="B34"><label>34.</label><mixed-citation>Linear and Quasilinear Parabolic Problems : Vol. II: Function Spaces / H. Amann. – Cham : Springer Nature Switzerland AG, 2019. – 462 p.</mixed-citation></ref></ref-list></back></article>
