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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">mathnas</journal-id><journal-title-group><journal-title xml:lang="ru">Труды Института математики НАН Беларуси</journal-title><trans-title-group xml:lang="en"><trans-title>Proceedings of the Institute of Mathematics of the NAS of Belarus</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1812-5093</issn><publisher><publisher-name>Институт математики НАН Беларуси</publisher-name></publisher></journal-meta><article-meta><article-id custom-type="elpub" pub-id-type="custom">mathnas-43</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>ДИСКРЕТНАЯ МАТЕМАТИКА И МАТЕМАТИЧЕСКАЯ КИБЕРНЕТИКА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>DISCRETE MATHEMATICS AND MATHEMATICAL CYBERNETICS</subject></subj-group></article-categories><title-group><article-title>Невыступающие фасады конуса полностью положительных матриц</article-title><trans-title-group xml:lang="en"><trans-title>Non-exposed faces of the cone of completely positive matrices</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Костюкова</surname><given-names>О. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Kostyukova</surname><given-names>O. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Минск</p></bio><bio xml:lang="en"><p>Minsk</p></bio><email xlink:type="simple">kostyukova@im-bas-net.by</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Институт математики НАН Беларуси</institution></aff><aff xml:lang="en"><institution>Institute of Mathematics of the National Academy of Sciences of Belarus,</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2024</year></pub-date><pub-date pub-type="epub"><day>03</day><month>03</month><year>2025</year></pub-date><volume>32</volume><issue>2</issue><fpage>56</fpage><lpage>68</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Костюкова О.И., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Костюкова О.И.</copyright-holder><copyright-holder xml:lang="en">Kostyukova O.I.</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://mathnas.ejournal.by/jour/article/view/43">https://mathnas.ejournal.by/jour/article/view/43</self-uri><abstract><p>В данной работе мы рассматриваем конус полностью положительных матриц. К настоящему время в литературе были построены некоторые семейства невыступающих полиэдральных фасадов этого конуса. Мотивированные этими результатами, в данной работе мы продолжаем изучение свойств невыступающих фасадов конуса полностью положительных матриц. Доказаны условия, выполнение которых необходимо и достаточно для того, чтобы фасад этого конуса был невыступающим. Также получены достаточные условия, которые можно легко проверить численно. Показано, что для любого $p\geqslant 6$ существуют невыступающие неполиэдральные фасады конуса $p\times p$ полностью положительных матриц. Приведены иллюстративные примеры</p></abstract><trans-abstract xml:lang="en"><p>In this paper, we consider the cone of completely positive matrices. Currently, some families of non-exposed polyhedral faces of this cone were constructed. Inspired by these results, in this paper, we continue the study of the existence and properties of non-exposed faces of the cone of completely positive matrices. We prove a criterion for a face of this cone to be non-exposed. We also provide sufficient conditions that can be easily checked numerically. We show that for any $p\geqslant 6$, there exist non-exposed non-polyhedral faces of the cone of $p\times p$ completely positive matrices. Illustrative examples are given</p></trans-abstract><kwd-group xml:lang="ru"><kwd>коническая оптимизация</kwd><kwd>полностью положительные матрицы</kwd><kwd>$K$-полуопределенные матрицы</kwd><kwd>фасад конуса</kwd><kwd>выступающие и невыступающие фасады конуса</kwd></kwd-group><kwd-group xml:lang="en"><kwd>conic optimization</kwd><kwd>completely positive matrices</kwd><kwd>$K$-semidefinite matrices</kwd><kwd>a face of a cone</kwd><kwd>exposed and non-exposed faces of a cone</kwd></kwd-group><funding-group><funding-statement xml:lang="en">This work was supported by the Institute of Mathematics of the National Academy of Sciences of Belarus within the framework of the state programme ”Convergence–2025”, tasks 1.3.01 and 1.3.04.</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">Anjos M. F., Lasserre J. B. (eds). 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