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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">mireabulletin</journal-id><journal-title-group><journal-title xml:lang="ru">Russian Technological Journal</journal-title><trans-title-group xml:lang="en"><trans-title>Russian Technological Journal</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2782-3210</issn><issn pub-type="epub">2500-316X</issn><publisher><publisher-name>RTU MIREA</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32362/2500-316X-2024-12-4-51-58</article-id><article-id custom-type="edn" pub-id-type="custom">VOQEBL</article-id><article-id custom-type="elpub" pub-id-type="custom">mireabulletin-962</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>РОБОТИЗИРОВАННЫЕ КОМПЛЕКСЫ И СИСТЕМЫ. ТЕХНОЛОГИИ ДИСТАНЦИОННОГО ЗОНДИРОВАНИЯ НЕРАЗРУШАЮЩЕГО КОНТРОЛЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MULTIPLE ROBOTS (ROBOTIC CENTERS) AND SYSTEMS. REMOTE SENSING AND NON-DESTRUCTIVE TESTING</subject></subj-group></article-categories><title-group><article-title>Решение томографической задачи с использованием дихотомической схемы дискретизации в полярных координатах и парциальных системных матриц, инвариантных к вращениям</article-title><trans-title-group xml:lang="en"><trans-title>Tomographic task solution using a dichotomous discretization scheme in polar coordinates and partial system matrices invariant to rotations</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0009-8428-9588</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Манушкин</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Manushkin</surname><given-names>A. А.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Манушкин Алексей Анатольевич, к.ф.-м.н., ведущий научный сотрудник</p><p>109316, Россия, Москва, Волгоградский просп., д. 42</p><p>Scopus Author ID 6507658966</p></bio><bio xml:lang="en"><p>Alexey A. Manushkin, Cand. Sci. (Phys.-Math.), Leading Researcher</p><p>42, Volgogradskii pr., Moscow, 109316</p><p>Scopus Author ID 6507658966</p></bio><email xlink:type="simple">manushkinaa@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8806-0603</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Потрахов</surname><given-names>Н. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Potrachov</surname><given-names>N. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Потрахов Николай Николаевич, д.т.н., заведующий кафедрой электронных приборов и устройств; главный научный сотрудник</p><p>197022, Санкт-Петербург, ул. Профессора Попова, д. 5, литера Ф</p><p>Scopus Author ID 8689381700</p></bio><bio xml:lang="en"><p>Nikolay N. Potrachov, Dr. Sci. (Eng.), Head of the Department of Electronic Instruments and Devices; Chief Researcher</p><p>5, ul. Professora Popova, St. Petersburg, 197022</p><p>Scopus Author ID 8689381700</p></bio><email xlink:type="simple">nnpotrahov@epu.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0000-0760-6222</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Степанов</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Stepanov</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Степанов Александр Вячеславович, к.т.н., начальник отдела промышленной интроскопии и диагностики</p><p>109316, Москва, Волгоградский просп., д. 42</p></bio><bio xml:lang="en"><p>Alexander V. Stepanov, Cand. Sci. (Eng.), Head of the Department of Industrial Introscopy and Diagnostics</p><p>42, Volgogradskii pr., Moscow, 109316</p></bio><email xlink:type="simple">stepanov_a@x-ray.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5197-2465</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Усачев</surname><given-names>Е. Ю.</given-names></name><name name-style="western" xml:lang="en"><surname>Usachev</surname><given-names>E. Yu.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Усачев Евгений Юрьевич, к.т.н., учредитель</p><p>109316, Россия, Москва, Волгоградский просп., д. 42</p><p>Scopus Author ID 55193172600</p></bio><bio xml:lang="en"><p>Evgeny Yu. Usachev, Cand. Sci. (Eng.), Founder</p><p>42, Volgogradskii pr., Moscow, 109316</p><p>Scopus Author ID 55193172600</p></bio><email xlink:type="simple">usachev_e@x-ray.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ООО «Диагностика-М»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Diagnostika-M</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ФГАОУ ВО «Санкт-Петербургский государственный электротехнический университет «ЛЭТИ» им. В.И. Ульянова (Ленина) (СПбГЭТУ «ЛЭТИ»)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Saint Petersburg Electrotechnical University LETI</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>05</day><month>08</month><year>2024</year></pub-date><volume>12</volume><issue>4</issue><elocation-id>51–58</elocation-id><permissions><copyright-statement>Copyright &amp;#x00A9; Манушкин А.А., Потрахов Н.Н., Степанов А.В., Усачев Е.Ю., 2024</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Манушкин А.А., Потрахов Н.Н., Степанов А.В., Усачев Е.Ю.</copyright-holder><copyright-holder xml:lang="en">Manushkin A.А., Potrachov N.N., Stepanov A.V., Usachev E.Y.</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://www.rtj-mirea.ru/jour/article/view/962">https://www.rtj-mirea.ru/jour/article/view/962</self-uri><abstract><p>Цели. Цель работы состояла в создании эффективного итерационного алгоритма для томографической реконструкции объектов с большими объемами исходных данных. В отличие от сверточного алгоритма проецирования, широко используемого в коммерческих промышленных и медицинских томографах, алгебраические итерационные методы реконструкции используют значительные объемы памяти и характеризуются большими временными затратами на реконструкцию. В то же время итерационные методы позволяют решать более широкий круг диагностических задач, где требуется большая точность реконструкции, а также в случаях использования ограниченного объема данных при малоракурсной съемке или съемке с ограниченным угловым диапазоном.Методы. Особенностью созданного алгоритма является использование полярной системы координат, в которой проекционные системные матрицы инвариантны по отношению к вращению объекта. Это дает возможность значительно сократить объемы памяти для хранения проекционных матриц и использовать для реконструкции графические процессоры. В отличие от простой полярной системы координат, используемой ранее, нами была использована система координат с дихотомическим делением поля реконструкции, что позволяет обеспечить инвариантность к вращениям и в тоже время достаточно равномерное распределение пространственного разрешения по полю реконструкции.Результаты. Был разработан алгоритм реконструкции, основанный на использовании парциальных системных матриц, соответствующих дихотомическому делению поля изображения на парциальные кольцевые области реконструкции. С использованием цифровых фантомов Шеппа – Логана и Де Фриза были исследованы особенности работы предложенного алгоритма реконструкции и показана его применимость для решения томографических задач.Выводы. Предложенный алгоритм дает возможность реализовать алгебраическую реконструкцию изображения с использованием стандартных библиотек для работы с разреженными матрицами на базе настольных компьютеров с графическими процессорами.</p></abstract><trans-abstract xml:lang="en"><p>Objectives. The purpose of this work was to create an effective iterative algorithm for the tomographic reconstruction of objects with large volumes of initial data. Unlike the convolutional projection algorithm, widely used in commercial industrial and medical tomographic devices, algebraic iterative reconstruction methods use significant amounts of memory and typically involve long reconstruction times. At the same time, iterative methods enable a wider range of diagnostic tasks to be resolved where greater accuracy of reconstruction is required, as well as in cases where a limited amount of data is used for sparse-view angle shooting or shooting with a limited angular range.Methods. A feature of the algorithm thus created is the use of a polar coordinate system in which the projection system matrices are invariant with respect to the rotation of the object. This enables a signification reduction of the amount of memory required for system matrices storage and the use of graphics processors for reconstruction. Unlike the simple polar coordinate system used earlier, we used a coordinate system with a dichotomous division of the reconstruction field enabling us to ensure invariance to rotations and at the same time a fairly uniform distribution of spatial resolution over the reconstruction field.Results. A reconstruction algorithm was developed on the basis of the use of partial system matrices corresponding to the dichotomous division of the image field into partial annular reconstruction regions. A 2D and 3D digital phantom was used to show the features of the proposed reconstruction algorithm and its applicability to solving tomographic problems.Conclusions. The proposed algorithm allows algebraic image reconstruction to be implemented using standard libraries for working with sparse matrices based on desktop computers with graphics processors.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>неразрушающий контроль</kwd><kwd>компьютерная томография</kwd><kwd>итерационный алгоритм</kwd><kwd>системная матрица</kwd></kwd-group><kwd-group xml:lang="en"><kwd>nondestructive technics</kwd><kwd>X-ray computed tomography</kwd><kwd>iterative algorithm</kwd><kwd>system matrix</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа проводится при финансовой поддержке Министерства образования и науки Российской Федерации (по Соглашению с Минобрнауки России от 09 февраля 2023 г. № 075-11-2023-006, идентификатор государственного контракта – 000000S407523Q6V0002).</funding-statement><funding-statement xml:lang="en">The work was financially supported by the Ministry of Education and Science of the Russian Federation (Agreement with the Ministry of Education and Science of the Russian Federation dated February 09, 2023, No. 075-11-2023-006, State Contract Identifier 000000S407523Q6V0002).</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">Feldkamp L.A., Davis L.C., Kress J.W. 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