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<article article-type="research-article" dtd-version="1.1" 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">
  <front>
    <journal-meta>
      <issn publication-format="print">1683-3414</issn>
      <issn publication-format="electronic">1814-0807</issn>
      <journal-title-group>
        <journal-title>Владикавказский математический журнал</journal-title>
        <trans-title-group xml:lang="en">
          <trans-title>Vladikavkaz Mathematical Journal</trans-title>
        </trans-title-group>
      </journal-title-group>
      <publisher>
        <publisher-name>Южный математический институт - филиал Федерального государственного бюджетного учреждения науки Федерального научного центра «Владикавказский научный центр Российской академии наук» (ЮМИ ВНЦ РАН)</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>О продолжении линейных селекторов</article-title>
      </title-group>
      <trans-title-group xml:lang="en">
        <trans-title>On Extension of Linear Selectors</trans-title>
      </trans-title-group>
      <article-id pub-id-type="doi">10.46698/o1056-6445-9027-m</article-id>
      <article-id pub-id-type="publisher-id">18586</article-id>
      <pub-date publication-format="electronic" date-type="pub">
        <month>03</month>
        <year>2026</year>
      </pub-date>
      <volume>28</volume>
      <issue>1</issue>
      <fpage>98</fpage>
      <lpage>107</lpage>
      <self-uri xlink:href="https://vmj.ru/archive/detail.php?ELEMENT_ID=18586&amp;SECTION_ID=656">https://vmj.ru/archive/detail.php?ELEMENT_ID=18586&amp;SECTION_ID=656</self-uri>
      <contrib-group>
        <contrib contrib-type="author">
          <name-alternatives>
            <name xml:lang="ru">
              <surname>Кусраева</surname>
              <given-names>З. А.</given-names>
            </name>
            <name xml:lang="en">
              <surname>Kusraeva</surname>
              <given-names>Z. A.</given-names>
            </name>
          </name-alternatives>
          <email>zali13@mail.ru</email>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name-alternatives>
            <name xml:lang="ru">
              <surname>Саадулаева</surname>
              <given-names>А. А.</given-names>
            </name>
            <name xml:lang="en">
              <surname>Saadulaeva</surname>
              <given-names>A. A.</given-names>
            </name>
          </name-alternatives>
          <email>gelieva00@mail.ru</email>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
      </contrib-group>
      <aff-alternatives id="aff1">
        <aff xml:lang="ru">Владикавказский научный центр РАН, Россия, 363110, с. Михайловское, ул. Вильямса, 1</aff>
        <aff xml:lang="en">Vladikavkaz Scientific Center of the Russian Academy of Sciences, 1 Williams St., Mikhaylovskoye Village 363110, Russia</aff>
      </aff-alternatives>
      <abstract>Рассматривается секвенциально полное топологическое векторное пространство \(Y\) и линейно инвариантное семейство \(\mathcal{E}\) выпуклых подмножеств \(Y\). Будем говорить, что: \(\mathcal{E}\) обладает счетным свойством бинарного пересечения, если всякое счетное подсемейство попарно пересекающихся множеств имеет непустое пересечение; пара \((Y, \mathcal{E})\) допускает счетное продолжение линейных операторов, если для любых сепарабельного метризуемого топологического векторного пространства, его подпространства, нечетного замкнутозначного полунепрерывного сверху веера (субаддитивное положительное однородное многозначное отображение) и линейного оператора, определенного на подпространстве, и являющегося селектором данного веера, существует линейный селектор, продолжающий линейный оператор с подпространства на все пространство. Основной результат утверждает, что пара \((Y, \mathcal{E})\) допускает счетное продолжение линейных непрерывных операторов, если \(\mathcal{E}\) обладает счетным свойством бинарного пересечения. Обращение этого результата также имеет место при том дополнительном предположении, что рассматриваемое топологическое векторное пространство локально ограничено.</abstract>
      <trans-abstract xml:lang="en">We consider a sequentially complete topological vector space \(Y\) and a linearly invariant family \(\mathcal{E}\) of convex subsets of \(Y\). We say that: \(\mathcal{E}\) has the countable binary intersection property if every countable subfamily of pairwise intersecting sets has a nonempty intersection; a pair \((Y, \mathcal{E})\) is said to admit a countable extension of linear operators if for any separable metrizable topological vector space, its subspace, odd closed-valued upper semicontinuous fan (subadditive positively homogeneous set-valued mapping), and a linear operator defined on the subspace and being a selector of the given fan, there exists a linear selector that extends given linear operator from a subspace to the entire space. The main result states that the pair \((Y, \mathcal{E})\) admits a countable extension of continuous linear operators if \(E\) has the countable binary intersection property. The inverse to this result also holds under the additional assumption that the topological vector space under consideration is locally bounded. </trans-abstract>
      <kwd-group xml:lang="ru">
        <kwd>веер</kwd>
        <kwd>продолжение линейных операторов</kwd>
        <kwd>свойство счетного бинарного пересечения</kwd>
        <kwd>сепарабельность</kwd>
        <kwd>векторная решетка.</kwd>
      </kwd-group>
      <kwd-group xml:lang="en">
        <kwd>fan</kwd>
        <kwd>extension of linear operators</kwd>
        <kwd>countable binary intersection property</kwd>
        <kwd>separability</kwd>
        <kwd>vector lattice.</kwd>
      </kwd-group>
      <funding-group>
        <award-group>
          <funding-source>Исследование выполнено за счет гранта Российского научного фонда № 24-71-10094, https://rscf.ru/project/24-71-10094/.</funding-source>
        </award-group>
      </funding-group>
    </article-meta>
  </front>
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