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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="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Programming and Computer Software</journal-id><journal-title-group><journal-title xml:lang="en">Programming and Computer Software</journal-title><trans-title-group xml:lang="ru"><trans-title>Программирование</trans-title></trans-title-group></journal-title-group><issn publication-format="print">0132-3474</issn><issn publication-format="electronic">3034-5847</issn><publisher><publisher-name xml:lang="en">The Russian Academy of Sciences</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">695669</article-id><article-id pub-id-type="doi">10.7868/S3034584725040017</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>COMPUTER ALGEBRA</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>КОМПЬЮТЕРНАЯ АЛГЕБРА</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Computer-algebraic study of the asymptotic method for modeling waveguide propagation of electromagnetic radiation</article-title><trans-title-group xml:lang="ru"><trans-title>Компьютерно-алгебраическое исследование асимптотического метода моделирования волноводного распространения электромагнитного излучения</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Starikov</surname><given-names>D. A.</given-names></name><name xml:lang="ru"><surname>Стариков</surname><given-names>Д. А.</given-names></name></name-alternatives><email>starikov_da@pfur.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Divakov</surname><given-names>D. V.</given-names></name><name xml:lang="ru"><surname>Диваков</surname><given-names>Д. В.</given-names></name></name-alternatives><email>divakov_dv@pfur.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Tyutyunnik</surname><given-names>A. A.</given-names></name><name xml:lang="ru"><surname>Тютюнник</surname><given-names>А. А.</given-names></name></name-alternatives><email>tyutyunnik_aa@pfur.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Peoples' Friendship University of Russia</institution></aff><aff><institution xml:lang="ru">Российский университет дружбы народов</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-08-15" publication-format="electronic"><day>15</day><month>08</month><year>2025</year></pub-date><issue>4</issue><issue-title xml:lang="en">NO4 (2025)</issue-title><issue-title xml:lang="ru">№4 (2025)</issue-title><fpage>3</fpage><lpage>10</lpage><history><date date-type="received" iso-8601-date="2025-11-01"><day>01</day><month>11</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Russian Academy of Sciences</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Российская академия наук</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Russian Academy of Sciences</copyright-holder><copyright-holder xml:lang="ru">Российская академия наук</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/" start_date="2026-08-31"/></permissions><self-uri xlink:href="https://transsyst.ru/0132-3474/article/view/695669">https://transsyst.ru/0132-3474/article/view/695669</self-uri><abstract xml:lang="en"><p>This paper formulates an asymptotic method for investigating vector electromagnetic fields of waveguide modes in the adiabatic approximation. The asymptotic method in the zero approximation is reduced to the symbolic investigation of a homogeneous system of ordinary differential equations; higher approximations correspond to inhomogeneous systems of ordinary differential equations with a similar matrix of coefficients. Using the asymptotic method, symbolic solutions in the zero and first approximations are obtained.</p></abstract><trans-abstract xml:lang="ru"><p>В работе формулируется асимптотический метод исследования векторных электромагнитных полей волноводных мод в адиабатическом приближении. Асимптотический метод в нулевом приближении сводится к символьному исследованию однородной системы обыкновенных дифференциальных уравнений, старшим приближениям соответствуют неоднородные системы обыкновенных дифференциальных уравнений с аналогичной матрицей коэффициентов. В рамках асимптотического метода приводятся символьные решения в нулевом и первом приближениях.</p></trans-abstract><kwd-group xml:lang="en"><kwd>symbolic solution of linear equations</kwd><kwd>symbolic solution of differential equations</kwd><kwd>smoothly irregular waveguide</kwd><kwd>guided modes</kwd><kwd>asymptotic method</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>символьное решение линейных уравнений</kwd><kwd>символьное решение дифференциальных уравнений</kwd><kwd>плавно-нерегулярный волновод</kwd><kwd>направляемые моды</kwd><kwd>асимптотический метод</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Публикация выполнена при поддержке Программы стратегического академического лидерства РУДН, проект № 021934-0-000.</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Stevenson A.F. General Theory of Electromagnetic Horns // Journal of Applied Physics. 1951. Vol. 22. No. 12. 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