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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Solar-Terrestrial Physics</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Solar-Terrestrial Physics</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Солнечно-земная физика / Solnechno-Zemnaya Fizika / Solar-Terrestrial Physics</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">2712-9640</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">50155</article-id>
   <article-id pub-id-type="doi">10.12737/szf-84202206</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>Результаты  исследований</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>Results of current research</subject>
    </subj-group>
    <subj-group>
     <subject>Результаты  исследований</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">The first comparative analysis of meteor echo and sporadic scattering identified by a self-learned neural network in EKB and MAGW ISTP SB RAS radar data</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Первый сравнительный анализ метеорного эхо и спорадического рассеяния, идентифицированных самообучившейся нейронной сетью по данным радаров EKB и MAGW ИСЗФ СО РАН</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3837-8207</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Бернгардт</surname>
       <given-names>Олег Игоревич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Berngardt</surname>
       <given-names>Oleg Igorevich</given-names>
      </name>
     </name-alternatives>
     <email>berng@iszf.irk.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Институт солнечно-земной физики СО РАН</institution>
     <city>Иркутск</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Institute of Solar-Terrestrial Physics SB RAS</institution>
     <city>Irkutsk</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2022-12-24T19:09:02+03:00">
    <day>24</day>
    <month>12</month>
    <year>2022</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2022-12-24T19:09:02+03:00">
    <day>24</day>
    <month>12</month>
    <year>2022</year>
   </pub-date>
   <volume>8</volume>
   <issue>4</issue>
   <fpage>66</fpage>
   <lpage>76</lpage>
   <history>
    <date date-type="received" iso-8601-date="2022-05-04T00:00:00+03:00">
     <day>04</day>
     <month>05</month>
     <year>2022</year>
    </date>
    <date date-type="accepted" iso-8601-date="2022-09-19T00:00:00+03:00">
     <day>19</day>
     <month>09</month>
     <year>2022</year>
    </date>
   </history>
   <self-uri xlink:href="https://naukaru.ru/en/nauka/article/50155/view">https://naukaru.ru/en/nauka/article/50155/view</self-uri>
   <abstract xml:lang="ru">
    <p>В работе описана текущая версия алгоритма автоматической классификации сигналов (v.1.1), принимаемых радарами декаметрового когерентного рассеяния ИСЗФ СО РАН. Алгоритм представляет собой самообучающуюся нейронную сеть, определяющую тип рассеянных сигналов по результатам физического моделирования распространения радиоволн с использованием радарных данных и международных ссылочных моделей ионосферы и магнитного поля Земли. Используя данные радаров MAGW и EKB ИСЗФ СО РАН за 2021 г., алгоритм самостоятельно обучается группировать рассеянные сигналы на изначально неизвестные классы. Такое деление основано на физически интерпретируемых параметрах распространения радиоволн и измеренных радаром данных, при этом из 20 возможных скрытых классов выделяются 15 часто наблюдаемых, из которых 14 могут быть интерпретированы с физической точки зрения. Для демонстрации работы алгоритма представлен первый статистический анализ наблюдений сигналов, отнесенных алгоритмом к двум классам, интерпретируемым нами как рассеяние на метеорных следах и рассеяние с участием спорадического слоя E соответственно. На основе статистического анализа данных радаров EKB и MAGW за 2021–2022 гг. определены дальностно-высотные характеристики сигналов этих классов, показана корреляция между среднечасовыми количествами наблюдений обоих классов, а также их среднечасовыми продольными скоростями. Полученные результаты позволяют интерпретировать сигналы этих классов как метеорное эхо и спорадическое рассеяние соответственно и использовать их для изучения процессов взаимодействия нейтральной атмосферы, изучаемой по данным метеорного рассеяния, и нижней ионосферы, изучаемой по наблюдениям за спорадическим рассеянием. В настоящее время представленный алгоритм классификации работает на радарах ИСЗФ СО РАН в автоматическом режиме.</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>The paper describes the current version (v.1.1) of the algorithm for automatic classification of signals received by ISTP SB RAS decameter coherent scatter radars. The algorithm is a self-learning neural network that determines the type of scattered signals from the results of physical modeling of radio wave propagation, using radar data and international reference models of the ionosphere and geomagnetic field. According to MAGW and EKB ISTP SB RAS radar data for 2021, the algorithm self-learns to classify scattered signals into initially unknown classes based on physically interpreted parameters of radio wave propagation and data measured by the radar, with 15 frequently observed out of 20 possible hidden classes identified, 14 of which can be interpreted from a physical point of view. To demonstrate the operation of the algorithm, we present the first statistical analysis of observations of signals assigned by the algorithm to classes which we interpret as scattering by meteor trails and scattering with the sporadic E layer respectively. Through a statistical analysis of EKB and MAGW radar data during 2021–2022, we demonstrate the range-altitude characteristics of signals of these types. A correlation is shown between the hourly average numbers of observations of both classes, as well as between the hourly average line-of-sight velocities obtained for both classes. The results obtained make it possible to interpret these classes as a meteor echo and sporadic scattering respectively, and to use radar data to study the interaction between the neutral atmosphere (studied from meteor scattering data) and the lower ionosphere (studied from observations of sporadic scattering). Currently, this classification algorithm works in ISTP SB RAS radars in automatic mode.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>машинное обучение</kwd>
    <kwd>классификация сигналов</kwd>
    <kwd>радары когерентного рассеяния</kwd>
    <kwd>метеорное эхо</kwd>
    <kwd>спорадическое рассеяние</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>machine learning</kwd>
    <kwd>signal classification</kwd>
    <kwd>coherent scatter radars</kwd>
    <kwd>meteor echo</kwd>
    <kwd>sporadic scattering</kwd>
   </kwd-group>
   <funding-group>
    <funding-statement xml:lang="ru">Работа выполнена при финансовой поддержке совместного гранта РФФИ-CNRS № 21-55-15012. Эксплуатация радаров осуществлялась при финансовой поддержке Министерства науки и высшего образования Российской Федерации (субсидия № 075-ГЗ/С3569/278)</funding-statement>
    <funding-statement xml:lang="en">The work was financially supported by RFBR-CNRS Grant No. 21-55-15012. The radars were operated with the financial support of the Ministry of Science and Higher Education of the Russian Federation (subsidy No. 075-GZ/S3569/278)</funding-statement>
   </funding-group>
  </article-meta>
 </front>
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