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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">Discrete and Continuous Models and Applied Computational Science</journal-id><journal-title-group><journal-title xml:lang="en">Discrete and Continuous Models and Applied Computational Science</journal-title><trans-title-group xml:lang="ru"><trans-title>Discrete and Continuous Models and Applied Computational Science</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2658-4670</issn><issn publication-format="electronic">2658-7149</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">44730</article-id><article-id pub-id-type="doi">10.22363/2658-4670-2025-33-1-10-26</article-id><article-id pub-id-type="edn">AMSSFO</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Computer Science</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Информатика и вычислительная техника</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">Modeling and optimization of an M/M/1/K queue with single working vacation, feedback, and impatience timers under N-policy</article-title><trans-title-group xml:lang="ru"><trans-title>Моделирование и оптимизация очереди M/M/1/K с одиночным рабочим отпуском, обратной связью и таймерами нетерпимости в рамках N-политики</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0000-6668-0270</contrib-id><name-alternatives><name xml:lang="en"><surname>Kadi</surname><given-names>Abir</given-names></name><name xml:lang="ru"><surname>Кади</surname><given-names>Абир</given-names></name></name-alternatives><bio xml:lang="en"><p>PhD student, at Department of Mathematics, Laboratory of Applied Mathematics</p></bio><email>abir.kadi@univ-bejaia.dz</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9414-714X</contrib-id><name-alternatives><name xml:lang="en"><surname>Boualem</surname><given-names>Mohamed</given-names></name><name xml:lang="ru"><surname>Буалем</surname><given-names>Мохамед</given-names></name></name-alternatives><bio xml:lang="en"><p>Full Professor of Applied Mathematics at the Department of Automation, Telecommunications, and Electronics at the University of Bejaia, Algeria. Permanent Researcher at the Research Unit LaMOS</p></bio><email>mohammed.boualem@univ-bejaia.dz</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-9185-3433</contrib-id><name-alternatives><name xml:lang="en"><surname>Touche</surname><given-names>Nassim</given-names></name><name xml:lang="ru"><surname>Туш</surname><given-names>Нассим</given-names></name></name-alternatives><bio xml:lang="en"><p>Full Professor of Mathematics at Department of Operations research, Faculty of Exact Sciences, Research Unit LaMOS</p></bio><email>nassim.touche@univ-bejaia.dz</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0009-1221-9898</contrib-id><name-alternatives><name xml:lang="en"><surname>Dehimi</surname><given-names>Aimen</given-names></name><name xml:lang="ru"><surname>Дехими</surname><given-names>Аймен</given-names></name></name-alternatives><bio xml:lang="en"><p>PhD student, at Department of Mathematics, Laboratory of Applied Mathematics</p></bio><email>aimen.dehimi@univ-bejaia.dz</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">University of Bejaia</institution></aff><aff><institution xml:lang="ru">Университет Беджаи</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2025-06-15" publication-format="electronic"><day>15</day><month>06</month><year>2025</year></pub-date><volume>33</volume><issue>1</issue><issue-title xml:lang="en">VOL 33, NO1 (2025)</issue-title><issue-title xml:lang="ru">ТОМ 33, №1 (2025)</issue-title><fpage>10</fpage><lpage>26</lpage><history><date date-type="received" iso-8601-date="2025-06-27"><day>27</day><month>06</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2025, Kadi A., Boualem M., Touche N., Dehimi A.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2025, Кади А., Буалем М., Туш Н., Дехими А.</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="en">Kadi A., Boualem M., Touche N., Dehimi A.</copyright-holder><copyright-holder xml:lang="ru">Кади А., Буалем М., Туш Н., Дехими А.</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/miph/article/view/44730">https://journals.rudn.ru/miph/article/view/44730</self-uri><abstract xml:lang="en"><p style="text-align: justify;">This work presents an intensive study of a single server finite-capacity queueing model with impatience timers which depend on the server’s states, feedback, and a single working vacation policy operating under an <span class="math inline">\(N\)</span>-policy discipline. We examine the scenario where the server must wait for the number of customers to reach <span class="math inline">\(N\)</span> to start a regular busy period; otherwise, the server will initiate a working vacation or switch to the dormant state if the number of customers increases. By applying the Markov recursive method, the steady-state probabilities were derived. Various performance metrics were visually depicted to assess diverse system parameter configurations. After constructing the expected cost function of the model, Grey Wolf Optimization (GWO) algorithm is utilized to determine the optimum values of the service rates <span class="math inline">\(\mu^{*}\)</span> and <span class="math inline">\(\mu_{v}^{*}\)</span>. Numerical examples are provided to validate the theoretical findings, offering insights into this intricate system.</p></abstract><trans-abstract xml:lang="ru"><p style="text-align: justify;">Этот труд представляет собой интенсивное исследование модели очереди с одним сервером и конечной ёмкостью, с таймерами нетерпимости, зависящими от состояний сервера, с обратной связью и политикой одиночного рабочего отпуска, функционирующей в рамках дисциплины <span class="math inline">\(N\)</span>-политики. Мы рассматриваем сценарий, при котором сервер должен дождаться, пока количество клиентов не достигнет <span class="math inline">\(N\)</span>, чтобы начать обычный рабочий период; в противном случае сервер начнёт рабочий отпуск или перейдёт в неактивное состояние, если количество клиентов увеличится. С помощью метода Марковской рекурсии были получены вероятности в установившемся состоянии. Различные показатели производительности были визуально изображены для оценки различных конфигураций параметров системы. После построения ожидаемой функции стоимости модели используется алгоритм Оптимизация серых волков (GWO) для определения оптимальных значений коэффициентов обслуживания <span class="math inline">\(\mu^{}\)</span> и <span class="math inline">\(\mu\_{v}^{}\)</span>. Приведены числовые примеры для проверки теоретических выводов, что позволяет глубже понять эту сложную систему.</p></trans-abstract><kwd-group xml:lang="en"><kwd>Queueing system with impatience, N-policy, vacation policy, feedback, GWO algorithm, cost optimization</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>система очередей с нетерпимостью, N-политика, политика отпуска, обратная связь, алгоритм GWO, оптимизация стоимости</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Bouchentouf, A. A., Cherfaoui, M. &amp; Boualem, M. 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