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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">cndcgs</journal-id>
      <journal-title-group>
        <journal-title>Challenges to national defence in contemporary geopolitical situation</journal-title>
      </journal-title-group>
      <issn pub-type="epub">2538-8959</issn>
      <issn pub-type="ppub">2669-2023</issn>
      <publisher>
        <publisher-name>LKA</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id">63_NAKONECHNYI</article-id>
      <article-id pub-id-type="doi">10.47459/cndcgs.2026.63</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Article</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Guaranteed RMS Estimates of Spectral Functions and Radiation Sources from Observations with Random Disturbances</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Nakonechnyi</surname>
            <given-names>Oleksandr</given-names>
          </name>
          <email xlink:href="mailto:oleksandrnakonechny@knu.ua">oleksandrnakonechny@knu.ua</email>
          <xref ref-type="aff" rid="j_cndcgs_aff_000"/>
          <xref ref-type="corresp" rid="cor1">∗</xref>
        </contrib>
        <aff id="j_cndcgs_aff_000">Department of System Analysis and Decision Making Theory, Faculty of Computer Science and Cybernetics, Taras Shevchenko National University of Kyiv, Ukraine</aff>
        <contrib contrib-type="author">
          <name>
            <surname>Zinko</surname>
            <given-names>Petro</given-names>
          </name>
          <xref ref-type="aff" rid="j_cndcgs_aff_001"/>
        </contrib>
        <aff id="j_cndcgs_aff_001">Department of System Analysis and Decision Making Theory, Faculty of Computer Science and Cybernetics, Taras Shevchenko National University of Kyiv, Ukraine</aff>
        <contrib contrib-type="author">
          <name>
            <surname>Zinko</surname>
            <given-names>Taras</given-names>
          </name>
          <xref ref-type="aff" rid="j_cndcgs_aff_002"/>
        </contrib>
        <aff id="j_cndcgs_aff_002">Department of System Analysis and Decision Making Theory, Faculty of Computer Science and Cybernetics, Taras Shevchenko National University of Kyiv, Ukraine</aff>
        <contrib contrib-type="author">
          <name>
            <surname>Losieva</surname>
            <given-names>Mariia</given-names>
          </name>
          <xref ref-type="aff" rid="j_cndcgs_aff_003"/>
        </contrib>
        <aff id="j_cndcgs_aff_003">Department of System Analysis and Decision Making Theory, Faculty of Computer Science and Cybernetics, Taras Shevchenko National University of Kyiv, Ukraine</aff>
      </contrib-group>
      <author-notes>
        <corresp id="cor1"><label>∗</label>Corresponding author.</corresp>
      </author-notes>
      <volume>2026</volume>
      <issue>1</issue>
      <fpage>549</fpage>
      <lpage>558</lpage>
      <pub-date pub-type="epub">
        <day>09</day>
        <month>07</month>
        <year>2026</year>
      </pub-date>
      <permissions>
        <license license-type="open-access">
          <license-p>Creative Commons Attribution International License (CC BY)</license-p>
        </license>
      </permissions>
      <abstract>
        <p>In this article, we investigate the problem of estimating the spectral characteristics of the intensity of moving objects under stochastic uncertainty based on the results of measuring the magnitudes of wave fields at separate points. We assume that the unknown spectral functions belong to known sets from the functional space, and certain restrictions are given for the unknown correlation matrices. For linear guaranteed estimates of the set of linear functionals from spectral functions, we prove that the guaranteed mean square estimates are expressed in terms of solutions of a certain system of linear algebraic equations.</p>
      </abstract>
      <kwd-group>
        <label>Keywords</label>
        <kwd>linear estimate of the vector</kwd>
        <kwd>guaranteed estimate of the vector</kwd>
        <kwd>vector estimation error</kwd>
        <kwd>spectral function</kwd>
        <kwd>moving radiation source</kwd>
        <kwd>stochastic uncertainty</kwd>
        <kwd>observation</kwd>
      </kwd-group>
    </article-meta>
  </front>
</article>
