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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">Contemporary Mathematics. Fundamental Directions</journal-id><journal-title-group><journal-title xml:lang="en">Contemporary Mathematics. Fundamental Directions</journal-title><trans-title-group xml:lang="ru"><trans-title>Современная математика. Фундаментальные направления</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2413-3639</issn><issn publication-format="electronic">2949-0618</issn><publisher><publisher-name xml:lang="en">Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">46625</article-id><article-id pub-id-type="doi">10.22363/2413-3639-2025-71-3-443-451</article-id><article-id pub-id-type="edn">FMBVJU</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Articles</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Статьи</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">Continuous generation population model with discontinuous life cycle characteristics</article-title><trans-title-group xml:lang="ru"><trans-title>Непрерывная популяционная модель поколений с разрывными характеристиками жизненного цикла</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Perevaryukha</surname><given-names>A. Yu.</given-names></name><name xml:lang="ru"><surname>Переварюха</surname><given-names>А. Ю.</given-names></name></name-alternatives><email>madelf@rambler.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Saint Petersburg Institute for Informatics and Automation of the RAS</institution></aff><aff><institution xml:lang="ru">Санкт-Петербургский Федеральный исследовательский центр РАН</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-10-15" publication-format="electronic"><day>15</day><month>10</month><year>2025</year></pub-date><volume>71</volume><issue>3</issue><issue-title xml:lang="en">Proceedings of the Crimean Autumn Mathematical School-Symposium</issue-title><issue-title xml:lang="ru">Труды Крымской осенней математической школы-симпозиума</issue-title><fpage>443</fpage><lpage>451</lpage><history><date date-type="received" iso-8601-date="2025-10-23"><day>23</day><month>10</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Perevaryukha A.Y.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Переварюха А.Ю.</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Perevaryukha A.Y.</copyright-holder><copyright-holder xml:lang="ru">Переварюха А.Ю.</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-nc/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/CMFD/article/view/46625">https://journals.rudn.ru/CMFD/article/view/46625</self-uri><abstract xml:lang="en"><p>Traditionally, continuous models of mathematical biology are focused on the dynamics of interacting populations as stationary homogeneous entities. The state of the populations in the equations is governed by factors common to all individuals <span class="math">\( \forall t,N(t) \)</span>: reproductive efficiency, mortality, living space limitations, or resource limitations. Many species exist with nonoverlapping generation sequences, replacing each other under different seasonal conditions. The number of annual generations is an important characteristic of the ecology of a species when occupying a new range. The length of the life cycle and the index of reproductive activity <italic>r </italic>in adjacent generations of insects in a range vary due to the need for wintering. Fluctuations in these values affect rapid population outbreaks. It is shown that the use of discrete models <span class="math">\( x_{n+1}=\psi(x_n;r)\varphi(x_{n-i})-\Xi \)</span> is unrealistic for fundamental reasons. The appearance of cycles <span class="math">\( p\neq2^i \)</span> in the order of Sharkovsky's theorem is excessive for the analysis of populations and the forecast of mass reproductions of insects. The article proposes a method for organizing models of the conjugate development of a succession of generations in a system of discontinuous differential equations as a sequence of boundary-value problems. The model is event-based redefined to obtain a solution on time intervals corresponding to the conditions of the season. The model taking into account competition and delayed regulation is relevant for the analysis of a sequence of peaks in pest activity, which are characterized by individual extremely numerous generations.</p></abstract><trans-abstract xml:lang="ru"><p>Традиционно непрерывные модели математической биологии направлены на динамику взаимодействующих популяций как стационарных гомогенных общностей. Состояние популяций в уравнениях регулируется общими для всех особей <span class="math">\( \forall t,N(t) \)</span> факторами эффективности воспроизводства, гибели, ограничения жизненного пространства или лимитом ресурсов. Существуют много видов с неперекрывающейся последовательностью поколений, сменяющих друг друга в разных сезонных условиях. Число годовых поколений --- важная характеристика экологии вида при захвате нового ареала. Длина жизненного цикла и показатель репродуктивной активности r у смежных поколений насекомых в ареале различны из-за необходимости зимовки. Колебания этих величин влияют на стремительные вспышки численности. Показано, что применение дискретных моделей <span class="math">\( x_{n+1}=\psi(x_n;r)\varphi(x_{n-i})-\Xi \)</span>  оказывается нереалистично по фундаментальным причинам. Появление циклов <span class="math">\( p\neq2^i \)</span> в порядке теоремы Шарковского избыточно для анализа популяций и прогноза массовых размножений насекомых. В статье предложен метод организации моделей сопряженного развития череды поколений в системе разрывных дифференциальных уравнений как последовательности краевых задач. Модель событийно переопределяется для получения решения на отрезках времени, соответствующих условиям сезона. Модель с учетом конкуренции и запаздывающей регуляции актуальна для анализа череды пиков активности вредителей, для которых характерны отдельные чрезвычайно многочисленные поколения.</p></trans-abstract><kwd-group xml:lang="en"><kwd>population modeling</kwd><kwd>continuous model</kwd><kwd>generational modeling</kwd><kwd>population cycle</kwd><kwd>survival dynamics</kwd><kwd>discontinuous differential equations</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>популяционное моделирование</kwd><kwd>непрерывная модель</kwd><kwd>моделирование поколений</kwd><kwd>популяционный цикл</kwd><kwd>динамика выживаемости</kwd><kwd>разрывные дифференциальные уравнения</kwd></kwd-group><funding-group/></article-meta><fn-group/></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Abbas S., Niezabitowski M., Grace S. 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