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<article article-type="research-article" dtd-version="1.3" 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" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">matmess</journal-id><journal-title-group><journal-title xml:lang="ru">Математические заметки СВФУ</journal-title><trans-title-group xml:lang="en"><trans-title>Mathematical notes of NEFU</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2411-9326</issn><issn pub-type="epub">2587-876X</issn><publisher><publisher-name>Северо-Восточный федеральный университет имени М.К. Аммосова</publisher-name></publisher></journal-meta><article-meta><article-id custom-type="elpub" pub-id-type="custom">matmess-493</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ</subject></subj-group></article-categories><title-group><article-title>NUMERICALLY SOLVING THE IDENTIFICATION PROBLEM FOR THE LOWER COEFFICIENT OF A PARABOLIC EQUATION</article-title><trans-title-group xml:lang="en"><trans-title>NUMERICALLY SOLVING THE IDENTIFICATION PROBLEM FOR THE LOWER COEFFICIENT OF A PARABOLIC EQUATION</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Vabishchevich</surname><given-names>P. N.</given-names></name><name name-style="western" xml:lang="en"><surname>Vabishchevich</surname><given-names>P. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>P. N. Vabishchevich</p><p>Nuclear Safety Institute, Russian Academy of Sciences 115191, Moscow, Russia </p></bio><bio xml:lang="en"><p>P. N. Vabishchevich</p><p>Nuclear Safety Institute, Russian Academy of Sciences 115191, Moscow, Russia</p></bio><email xlink:type="simple">vabishchevich@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Vasil′ev</surname><given-names>V. I.</given-names></name><name name-style="western" xml:lang="en"><surname>Vasil′ev</surname><given-names>V. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>V. I. Vasil′ev</p><p>North-Eastern Federal University, 677000, Yakutsk, Russia </p></bio><bio xml:lang="en"><p>V. I. Vasil′ev</p><p>North-Eastern Federal University, 677000, Yakutsk, Russia </p></bio><email xlink:type="simple">vasvasil@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Nuclear Safety Institute, Russian Academy of Sciences</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Nuclear Safety Institute, Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>North-Eastern Federal University</institution><country>Россия</country></aff><aff xml:lang="en"><institution>North-Eastern Federal University</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2014</year></pub-date><pub-date pub-type="epub"><day>10</day><month>07</month><year>2026</year></pub-date><volume>21</volume><issue>4</issue><fpage>71</fpage><lpage>87</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Vabishchevich P.N., Vasil′ev V.I., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Vabishchevich P.N., Vasil′ev V.I.</copyright-holder><copyright-holder xml:lang="en">Vabishchevich P.N., Vasil′ev V.I.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://matmess.elpub.ru/jour/article/view/493">https://matmess.elpub.ru/jour/article/view/493</self-uri><abstract><p>In the theory and practice of inverse problems for partial differential equations (PDEs) much attention is paid to the identification problem of coefficients from some additional information. This article deals with the problem of determining in a multidimensional parabolic equation the lower coefficient that depends only on time. To solve numerically a nonlinear inverse problem, linearized approximations in time are constructed using standard finite element procedures in space. The computational algorithm is based on a special decomposition, where the transition to a new time level is implemented via solving two standard elliptic problems. The numerical results presented here for a model 2D problem demonstrate capabilities of the proposed computational algorithms for approximate solving inverse problems.</p></abstract><trans-abstract xml:lang="en"><p>In the theory and practice of inverse problems for partial differential equations (PDEs) much attention is paid to the identification problem of coefficients from some additional information. This article deals with the problem of determining in a multidimensional parabolic equation the lower coefficient that depends only on time. To solve numerically a nonlinear inverse problem, linearized approximations in time are constructed using standard finite element procedures in space. The computational algorithm is based on a special decomposition, where the transition to a new time level is implemented via solving two standard elliptic problems. The numerical results presented here for a model 2D problem demonstrate capabilities of the proposed computational algorithms for approximate solving inverse problems.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>inverse problem</kwd><kwd>identification of the coefficient</kwd><kwd>parabolic partial differential equation</kwd><kwd>finite element approximation</kwd><kwd>difference scheme</kwd></kwd-group><kwd-group xml:lang="en"><kwd>inverse problem</kwd><kwd>identification of the coefficient</kwd><kwd>parabolic partial differential equation</kwd><kwd>finite element approximation</kwd><kwd>difference scheme</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">The authors were supported by the Russian Foundation for Basic Research (Grants 13–01– 00719 and 14–01–00785).</funding-statement><funding-statement xml:lang="en">The authors were supported by the Russian Foundation for Basic Research (Grants 13–01– 00719 and 14–01–00785).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Alifanov O. 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