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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">kaz29</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Казахстанско-Британского технического университета</journal-title><trans-title-group xml:lang="en"><trans-title>Herald of the Kazakh-British Technical University</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1998-6688</issn><issn pub-type="epub">2959-8109</issn><publisher><publisher-name>Казахстанско-Британский Технический Университет</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.55452/1998-6688-2026-23-2-108-123</article-id><article-id custom-type="elpub" pub-id-type="custom">kaz29-2890</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>МАТЕМАТИЧЕСКИЕ НАУКИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATHEMATICAL SCIENCES</subject></subj-group></article-categories><title-group><article-title>ЧИСЛЕННОЕ РЕШЕНИЕ ОБРАТНОЙ КОЭФФИЦИЕНТНОЙ ЗАДАЧИ АКУСТИКИ С ПРИМЕНЕНИЕМ ПРЕОБРАЗОВАНИЯ ЛАПЛАСА И МЕТОДА ДИФФЕРЕНЦИАЛЬНОЙ ЭВОЛЮЦИИ</article-title><trans-title-group xml:lang="en"><trans-title>NUMERICAL SOLUTION OF THE INVERSE COEFFICIENT ACOUSTIC PROBLEM USING LAPLACE TRANSFORM AND DIFFERENTIAL EVOLUTION METHOD</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5828-7820</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Синица</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Sinitsa</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>PhD, ассистент-профессор.</p><p>Алматы</p></bio><bio xml:lang="en"><p>PhD, Assistant Professor.</p><p>Almaty</p></bio><email xlink:type="simple">a.sinitsa@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0003-0772-4319</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Цхай</surname><given-names>Ю. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Tskhay</surname><given-names>Yu. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Магистр, лектор.</p><p>Алматы</p></bio><bio xml:lang="en"><p>MSc, Lecturer.</p><p>Almaty</p></bio><email xlink:type="simple">y.tskhay@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0003-0402-4720</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шкорко</surname><given-names>А. К.</given-names></name><name name-style="western" xml:lang="en"><surname>Shkorko</surname><given-names>A. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Магистр, лектор.</p><p>Алматы</p></bio><bio xml:lang="en"><p>MSc, Lecturer.</p><p>Almaty</p></bio><email xlink:type="simple">a.ukassova@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8142-6710</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кардук</surname><given-names>А. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Karduck</surname><given-names>A. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>PhD, профессор.</p><p>Фуртванген</p></bio><bio xml:lang="en"><p>PhD, Professor.</p><p>Furtwangen</p></bio><email xlink:type="simple">achim.karduck@hs-furtwangen.de</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Казахстанско-Британский технический университет<country>Казахстан</country></aff><aff xml:lang="en">Kazakh-British Technical University<country>Kazakhstan</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Университет Фуртвангена<country>Германия</country></aff><aff xml:lang="en">Furtwangen University<country>Germany</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>27</day><month>06</month><year>2026</year></pub-date><volume>23</volume><issue>2</issue><fpage>108</fpage><lpage>123</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Синица А.В., Цхай Ю.А., Шкорко А.К., Кардук А.П., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Синица А.В., Цхай Ю.А., Шкорко А.К., Кардук А.П.</copyright-holder><copyright-holder xml:lang="en">Sinitsa A.V., Tskhay Y.A., Shkorko A.K., Karduck A.P.</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://vestnik.kbtu.edu.kz/jour/article/view/2890">https://vestnik.kbtu.edu.kz/jour/article/view/2890</self-uri><abstract><p>В данной статье рассматривается решение обратной коэффициентной задачи для волнового уравнения, направленной на восстановление пространственного распределения скорости звука в неоднородной среде. Для решения прямой задачи применяется преобразование Лапласа, позволяющее исключить временную зависимость и перейти к обыкновенным дифференциальным уравнениям в частотной области, что существенно снижает вычислительные затраты. Обратная задача формулируется как оптимизационная: минимизация функционала невязки между рассчитанными и измеренными значениями акустического давления осуществляется с помощью стохастического метода глобальной оптимизации, дифференциальной эволюции. Численные эксперименты проводились на модели многослойной среды (песок, грунт, камень, вода, воздух) с использованием синтетических данных, зашумленных случайным образом. Предложен адаптивный комбинированный метод восстановления, позволяющий снизить влияние ошибок на границах сред. Результаты показывают высокую точность метода: относительная погрешность восстановления профиля скорости звука составила около от 2,5 до 4,3%, что подтверждает эффективность подхода для задач акустической диагностики и томографии.</p></abstract><trans-abstract xml:lang="en"><p>This paper addresses the solution of the inverse coefficient problem for the wave equation aimed at reconstructing the spatial distribution of the speed of sound in an inhomogeneous medium. The Laplace transform is applied to solve the direct problem, eliminating time dependence and reducing the problem to ordinary differential equations in the frequency domain, which significantly decreases computational costs. The inverse problem is formulated as an optimization task: minimizing the residual functional between calculated and measured acoustic pressure values using the stochastic global optimization method, Differential Evolution. Numerical experiments were conducted on a multilayer medium model (sand, soil, rock, water, air) using synthetic data with added random noise. An adaptive combined reconstruction method is proposed to reduce errors at medium boundaries. The results demonstrate high accuracy: the relative error of the sound speed profile reconstruction was approximately from 2.5 to 4.3%, confirming the approach's effectiveness for acoustic diagnostics and tomography applications.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>обратная задача</kwd><kwd>акустическое давление</kwd><kwd>скорость звука</kwd><kwd>преобразование Лапласа</kwd><kwd>дифференциальная эволюция</kwd><kwd>неоднородная среда</kwd><kwd>оптимизация</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Inverse problem</kwd><kwd>acoustic pressure</kwd><kwd>speed of sound</kwd><kwd>Laplace transform</kwd><kwd>differential evolution</kwd><kwd>inhomogeneous medium</kwd><kwd>optimization</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Uhlmann, G., and Zhai, J. On an inverse boundary value problem for a nonlinear elastic wave equation. 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