<!DOCTYPE article
PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.4 20190208//EN"
       "JATS-journalpublishing1.dtd">
<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" article-type="research-article" dtd-version="1.4" xml:lang="en">
 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Russian Journal of Earth Sciences</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Russian Journal of Earth Sciences</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Russian Journal of Earth Sciences</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">1681-1208</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">49571</article-id>
   <article-id pub-id-type="doi">10.2205/2026ES001087</article-id>
   <article-id pub-id-type="edn">urqewy</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>ORIGINAL ARTICLES</subject>
    </subj-group>
    <subj-group>
     <subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">Mathematical Technology for Estimating Parametric Functions of Non-Stationary Geophysical Signals</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Математическая технология оценивания параметрических функций нестационарных геофизических сигналов</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Гетманов</surname>
       <given-names>Виктор Григорьевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Getmanov</surname>
       <given-names>Viktor Grigoryevich</given-names>
      </name>
     </name-alternatives>
     <email>vgetm2015@yandex.ru</email>
     <bio xml:lang="ru">
      <p>доктор технических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>doctor of technical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
     <xref ref-type="aff" rid="aff-2"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3056-7465</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Пилипенко</surname>
       <given-names>Вячеслав Анатольевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Pilipenko</surname>
       <given-names>Vyacheslav Anatolievich</given-names>
      </name>
     </name-alternatives>
     <email>space.soliton@gmail.com</email>
     <bio xml:lang="ru">
      <p>доктор физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>doctor of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-3"/>
     <xref ref-type="aff" rid="aff-4"/>
     <xref ref-type="aff" rid="aff-5"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Геофизический центр РАН</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Geophysical Center of RAS</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Институт физики Земли им. О.Ю. Шмидта РАН</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Schmidt Institute of Physics of the Earth, RAS</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">Институт физики Земли им. О.Ю. Шмидта РАН</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Schmidt Institute of Physics of the Earth RAS</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-4">
    <aff>
     <institution xml:lang="ru">Геофизический центр РАН</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Geophysical Center RAS</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-5">
    <aff>
     <institution xml:lang="ru">Институт космических исследований</institution>
     <city>Москва</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Space Research Institute</institution>
     <city>Moscow</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2026-04-07T14:44:47+03:00">
    <day>07</day>
    <month>04</month>
    <year>2026</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2026-04-07T14:44:47+03:00">
    <day>07</day>
    <month>04</month>
    <year>2026</year>
   </pub-date>
   <volume>26</volume>
   <issue>1</issue>
   <elocation-id>ES1013</elocation-id>
   <history>
    <date date-type="received" iso-8601-date="2025-08-26T00:00:00+03:00">
     <day>26</day>
     <month>08</month>
     <year>2025</year>
    </date>
    <date date-type="accepted" iso-8601-date="2025-11-18T00:00:00+03:00">
     <day>18</day>
     <month>11</month>
     <year>2025</year>
    </date>
   </history>
   <self-uri xlink:href="https://rjes.ru/en/nauka/article/49571/view">https://rjes.ru/en/nauka/article/49571/view</self-uri>
   <abstract xml:lang="ru">
    <p>Разработана математическая технология цифровой обработки геофизических сигналов для оценивания нестационарных параметрических функций. Использовались двухэтапные аппроксимации c локальными моделями на первом и моделями взвешенных аппроксимационных усреднений на втором этапе. Сформированы алгоритмы вычислений оценок параметрических амплитудных и частотных функций, функций инкрементов/декрементов и частотных дисперсий. Предложены формулы погрешностей для оценок параметрических функций пульсаций. Реализованы примеры применения технологии для модельных и экспериментальных наблюдений. Продемонстрированы возможности технологии, позволяющие вычислить оценки функций частоты и функций производной частоты для геомагнитных пульсаций типа «жемчужины».</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>A mathematical technology for digital processing of geophysical signals has been developed for estimating non-stationary parametric functions. Two-stage approximations with local models in the first stage and weighted approximation averaging models in the second stage were used. Algorithms for calculating estimates of parametric amplitude and frequency functions, increment/decrement functions, and frequency dispersions have been developed. Error formulas for estimating parametric pulsation functions have been proposed. Examples of applying the technology to model and experimental observations have been implemented. The technology's capabilities are demonstrated, allowing for the calculation of frequency function estimates and frequency derivative functions for geomagnetic pulsations of the “pearl” type.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>геофизические сигналы</kwd>
    <kwd>геомагнитные пульсации</kwd>
    <kwd>нестационарные параметры</kwd>
    <kwd>двухэтапная аппроксимация</kwd>
    <kwd>локальные аппроксимации</kwd>
    <kwd>взвешенное усреднение</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>Geophysical signals</kwd>
    <kwd>geomagnetic pulsations</kwd>
    <kwd>non-stationary parameters</kwd>
    <kwd>two-stage approximation</kwd>
    <kwd>local approximations</kwd>
    <kwd>weighted averaging</kwd>
   </kwd-group>
   <funding-group>
    <funding-statement xml:lang="ru">Работа выполнена в рамках государственного задания Геофизического центра Российской академии наук и Института физики Земли им. О. Ю. Шмидта Российской академии наук, утверждённого Минобрнауки России.</funding-statement>
    <funding-statement xml:lang="en">This work was carried out within the framework of a state assignment from the Geophysical Center of the Russian Academy of Sciences and the Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences, approved by the Ministry of Education and Science of Russia.</funding-statement>
   </funding-group>
  </article-meta>
 </front>
 <body>
  <p></p>
 </body>
 <back>
  <ref-list>
   <ref id="B1">
    <label>1.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Алешкевич В. А. Курс общей физики. Оптика. — М. : Физматлит, 2011. — 320 с.</mixed-citation>
     <mixed-citation xml:lang="en">Afanasyev A. A., Rybolovlev A. A. and Ryzhkov A. P. Digital Signal Processing. — M. : Goryachaya Liniya-Telekom, 2019. — 356 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B2">
    <label>2.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Аникеев Д. А., Пенкин Г. О. и Стрижов В. В. Классификация физической активности человека с помощью локальных аппроксимирующих моделей // Информатика и её применения. — 2019. — Т. 13, № 1. — С. 40—48. — https://doi.org/10.14357/19922264190106.</mixed-citation>
     <mixed-citation xml:lang="en">Aleshkevitch V. A. Course in General Physics. Optics. — M. : Fizmatlit, 2011. — 320 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B3">
    <label>3.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Афанасьев А. А., Рыболовлев А. А. и Рыжков А. П. Цифровая обработка сигналов. — М. : Горячая Линия-Телеком, 2019. — 356 с.</mixed-citation>
     <mixed-citation xml:lang="en">Anikeyev D. A., Penkin G. O. and Strijov V. V. Local approximation models for human physical activity classification // Informatics and Applications. — 2019. — Vol. 13, no. 1. — P. 40–48. — https://doi.org/10.14357/19922264190106. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B4">
    <label>4.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г. Цифровая обработка нестационарных колебательных сигналов на основе локальных и сплайновых моделей. — М. : НИЯУ МИФИ, 2011. — 298 с.</mixed-citation>
     <mixed-citation xml:lang="en">Bioucas-Dias J., Katkovnik V., Astola J., et al. Absolute phase estimation: adaptive local denoising and global unwrapping // Applied Optics. — 2008. — Vol. 47, no. 29. — P. 5358–5369. — https://doi.org/10.1364/ao.47.005358.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B5">
    <label>5.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г. Локальные и сплайновые аппроксимации в цифровой обработке геомагнитных наблюдений // Чебышевский сборник. — 2019. — Т. 19, № 4. — С. 26—42. — https://doi.org/10.22405/2226-8383-2018-19-4-26-42.</mixed-citation>
     <mixed-citation xml:lang="en">Fedorov E. N., Pilipenko V. A., Engebretson M. J., et al. Transmission of a Magnetospheric Pc1 Wave Beam Through the Ionosphere to the Ground // Journal of Geophysical Research: Space Physics. — 2018. — Vol. 123, no. 5. — P. 3965–3982. — https://doi.org/10.1029/2018ja025338.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B6">
    <label>6.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г. Цифровая обработка сигналов с приложениями для геофизики и экспериментальной механике. — М. : Техносфера, 2021. — 356 с.</mixed-citation>
     <mixed-citation xml:lang="en">Fung L., Bearon R. N. and Hwang Y. A local approximation model for macroscale transport of biased active Brownian particles in a flowing suspension // Journal of Fluid Mechanics. — 2022. — Vol. 935. — A24. — https://doi.org/10.1017/jfm.2022.10.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B7">
    <label>7.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г., Дабагян Р. А. и Сидоров Р. В. Исследование характеристик геомагнитных пульсаций методом локальных аппроксимаций // Геомагнетизм и аэрономия. — 2016. — Т. 56, № 2. — С. 209—216. — https://doi.org/10.7868/s001679401602005x.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G. Digital Processing of Non-Stationary Oscillatory Signals Based on Local and Spline Models. — M. : MEPhI, 2011. — 298 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B8">
    <label>8.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г., Довбня Б. В. и Корнилов А. С. Оценка частотных и амплитудных параметров геомагнитных пульсаций типа «серпентинная эмиссия» // Геомагнетизм и аэрономия. — 2018. — Т. 58, № 4. — С. 540—550. — https://doi.org/10.1134/s0016794018040065.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G. Local and spline approximations in digital processing of geomagnetic observations // Chebyshevskii Sbornik. — 2019. — Vol. 19, no. 4. — P. 26–42. — https://doi.org/10.22405/2226-8383-2018-19-4-26-42. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B9">
    <label>9.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гетманов В. Г., Сидоров Р. В. и Дабагян Р. А. Метод фильтрации сигналов с использованием локальных моделей и функций взвешенного усреднения // Измерительная техника. — 2015. — № 9. — С. 52—57.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G. Digital Signal Processing With Applications for Geophysics and Experimental Mechanics. — M. : Tekhnosphera, 2021. — 356 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B10">
    <label>10.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Грибанова М. С. и Скурихина Е. А. Прогноз параметров вращения Земли с использованием методов локальной аппроксимации // Труды ИПА РАН. — 2020. — № 54. — С. 11—20. — https://doi.org/10.32876/ApplAstron.54.11-20.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G., Dabagyan R. A. and Sidorov R. V. Studying geomagnetic pulsation characteristics with the local approximation method // Geomagnetism and Aeronomy. — 2016. — Vol. 56, no. 2. — P. 195–202. — https://doi.org/10.1134/s0016793216020055.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B11">
    <label>11.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гульельми А. В. и Потапов А. С. Проблемы теории магнитосферных волн Pc1. Обзор // Солнечно-земная физика. — 2019. — Т. 5, № 3. — С. 102—109. — https://doi.org/10.12737/szf-53201910.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G., Dovbnya B. V. and Kornilov A. S. Estimating the Frequency and Amplitude Parameters of the Serpentine-Emission Type of Geomagnetic Pulsations // Geomagnetism and Aeronomy. — 2018. — Vol. 58, no. 4. — P. 523–532. — https://doi.org/10.1134/s0016793218040060.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B12">
    <label>12.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Гульельми А. В. и Троицкая В. А. Геомагнитные пульсации и диагностика магнитосферы. — М. : Наука, 1973. — 208 с.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G., Gvishiani A. D., Pilipenko V. A., et al. Estimation of Parameters of Non-stationary Geophysical Signals Based on Two-Stage Approximations Using Local Models // Russian Journal of Earth Sciences. — 2025. — Vol. 25. — ES2020. — https://doi.org/10.2205/2025es000979.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B13">
    <label>13.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Катковник В. Я. Непараметрическая идентификация и сглаживание данных (метод локальной аппроксимации). — М. : Наука, 1985. — 336 с.</mixed-citation>
     <mixed-citation xml:lang="en">Getmanov V. G., Sidorov R. V. and Dabagyan R. A. A Method of Filtering Signals Using Local Models and Weighted Averaging Functions // Measurement Techniques. — 2015. — Vol. 58, no. 9. — P. 1029–1036. — https://doi.org/10.1007/s11018-015-0837-5.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B14">
    <label>14.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Клейменова Н. Г. Геомагнитные пульсации // Модель космоса. Том 1. — М. : МГУ, 2007. — С. 611—626.</mixed-citation>
     <mixed-citation xml:lang="en">Gribanova M. S. and Skurikhina E. A. Prediction of Earth Rotation Parameters Using Local Approximation Techniques // Transactions of IAA RAS. — 2020. — No. 54. — P. 11–20. — https://doi.org/10.32876/ApplAstron.54.11-20. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B15">
    <label>15.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Михайлова О. С., Климушкин Д. Ю. и Магер П. Н. Современное состояние теории УНЧ-пульсаций диапазона Pc1 в плазме магнитосферы с тяжелыми ионами: Обзор // Солнечно-земная физика. — 2022. — Т. 8, № 1. — С. 3—18. — https://doi.org/10.12737/szf-81202201.</mixed-citation>
     <mixed-citation xml:lang="en">Guglielmi A. V. and Potapov A. S. Problems of the Pc1 magnetospheric wave theory. A review // Solar-Terrestrial Physics. — 2019. — Vol. 5, no. 3. — P. 87–92. — https://doi.org/10.12737/stp-53201910.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B16">
    <label>16.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Позднякова Д. Д., Пилипенко В. А., Носэ М. и др. Спутниковые и наземные наблюдения Pc1-пульсаций во время магнитной бури в марте 2023 г. // Солнечно-земная физика. — 2025. — Т. 11, № 2. — С. 56—68. — https://doi.org/10.12737/szf-112202505.</mixed-citation>
     <mixed-citation xml:lang="en">Guglielmi A. V. and Troitczkaya V. A. Geomagnetics Pulsations and Diagnosis of Magnetosphere. — M. : Nauka, 1973. — 208 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B17">
    <label>17.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Bioucas-Dias J., Katkovnik V., Astola J., et al. Absolute phase estimation: adaptive local denoising and global unwrapping // Applied Optics. — 2008. — Vol. 47, no. 29. — P. 5358–5369. — https://doi.org/10.1364/ao.47.005358.</mixed-citation>
     <mixed-citation xml:lang="en">Katkovnik V., Egiazarian K. and Astola J. Local Approximation Techniques in Signal and Image Processing. — SPIE, 2006. — 576 p. — https://doi.org/10.1117/3.660178.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B18">
    <label>18.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Fedorov E. N., Pilipenko V. A., Engebretson M. J., et al. Transmission of a Magnetospheric Pc1 Wave Beam Through the Ionosphere to the Ground // Journal of Geophysical Research: Space Physics. — 2018. — Vol. 123, no. 5. — P. 3965–3982. — https://doi.org/10.1029/2018ja025338.</mixed-citation>
     <mixed-citation xml:lang="en">Katkovnik V. Ya. Nonparametric Identification and Smoothing of Data (Local Approximation Method). — M. : Nauka, 1985. — 336 p. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B19">
    <label>19.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Fung L., Bearon R. N. and Hwang Y. A local approximation model for macroscale transport of biased active Brownian particles in a flowing suspension // Journal of Fluid Mechanics. — 2022. — Vol. 935. — A24. — https://doi.org/10.1017/jfm.2022.10.</mixed-citation>
     <mixed-citation xml:lang="en">Kleymenova N. G. Geomagnetics Pulsations // Model of space. Volume 1. — M. : MGU, 2007. — P. 611–626. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B20">
    <label>20.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Getmanov V. G., Gvishiani A. D., Pilipenko V. A., et al. Estimation of Parameters of Non-stationary Geophysical Signals Based on Two-Stage Approximations Using Local Models // Russian Journal of Earth Sciences. — 2025. — Vol. 25. — ES2020. — https://doi.org/10.2205/2025es000979.</mixed-citation>
     <mixed-citation xml:lang="en">Liu J., Shiokawa K., Oyama S.-I., et al. A Statistical Study of Longitudinal Extent of Pc1 Pulsations Using Seven PWING Ground Stations at Subauroral Latitudes // Journal of Geophysical Research: Space Physics. — 2023. — Vol. 128, no. 1. — https://doi.org/10.1029/2021ja029987.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B21">
    <label>21.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Katkovnik V., Egiazarian K. and Astola J. Local Approximation Techniques in Signal and Image Processing. — SPIE, 2006. — 576 p. — https://doi.org/10.1117/3.660178.</mixed-citation>
     <mixed-citation xml:lang="en">Makur A. A Study of Local Approximation in Information Theory. — Massachusetts Institute of Technology, 2015. — 171 p.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B22">
    <label>22.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Liu J., Shiokawa K., Oyama S.-I., et al. A Statistical Study of Longitudinal Extent of Pc1 Pulsations Using Seven PWING Ground Stations at Subauroral Latitudes // Journal of Geophysical Research: Space Physics. — 2023. — Vol. 128, no. 1. — https://doi.org/10.1029/2021ja029987.</mixed-citation>
     <mixed-citation xml:lang="en">Mallat S. A wavelet tour of signal processing. Second Edition. — Academic Press, 1999. — 671 p.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B23">
    <label>23.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Makur A. A Study of Local Approximation in Information Theory. — Massachusetts Institute of Technology, 2015. — 171 p.</mixed-citation>
     <mixed-citation xml:lang="en">Matsuda S., Miyoshi Y., Kasahava Y., et al. Multipoint Measurement of Fine-Structured EMIC Waves by Arase, Van Allen Probe A, and Ground Stations // Geophysical Research Letters. — 2021. — Vol. 48, no. 23. — https://doi.org/10.1029/2021gl096488.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B24">
    <label>24.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Mallat S. A wavelet tour of signal processing. Second Edition. — Academic Press, 1999. — 671 p.</mixed-citation>
     <mixed-citation xml:lang="en">Mikhailova O. S., Klimushkin D. Yu. and Mager P. N. The current state of the theory of Pc1 range ULF pulsations in magnetospheric plasma with heavy ions: A review // Solnechno-Zemnaya Fizika. — 2022. — Vol. 8, no. 1. — P. 3–18. — https://doi.org/10.12737/szf-81202201. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B25">
    <label>25.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Matsuda S., Miyoshi Y., Kasahava Y., et al. Multipoint Measurement of Fine-Structured EMIC Waves by Arase, Van Allen Probe A, and Ground Stations // Geophysical Research Letters. — 2021. — Vol. 48, no. 23. — https://doi.org/10.1029/2021gl096488.</mixed-citation>
     <mixed-citation xml:lang="en">Nie Y., Wang Y., Sun W., et al. The Local Approximation Method for Structural Optimization // Applied Mechanics and Materials. — 2014. — Vol. 575. — P. 854–858. — https://doi.org/10.4028/www.scientific.net/amm.575.854.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B26">
    <label>26.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Nie Y., Wang Y., Sun W., et al. The Local Approximation Method for Structural Optimization // Applied Mechanics and Materials. — 2014. — Vol. 575. — P. 854–858. — https://doi.org/10.4028/www.scientific.net/amm.575.854.</mixed-citation>
     <mixed-citation xml:lang="en">Pozdnyakova D. D., Pilipenko V. A., Nose M., et al. Satellite and ground-based observations of Pc1 pulsations during a magnetic storm in March 2023 // Solnechno-Zemnaya Fizika. — 2025. — Vol. 11, no. 2. — P. 56–68. — https://doi.org/10.12737/szf-112202505. — (In Russian).</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B27">
    <label>27.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Savelyev I. V. Physics A General Course. Volume 1. Mechanics, Molecular Physics. — M. : Mir, 1979. — 439 p.</mixed-citation>
     <mixed-citation xml:lang="en">Savelyev I. V. Physics A General Course. Volume 1. Mechanics, Molecular Physics. — M. : Mir, 1979. — 439 p.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B28">
    <label>28.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Time-Frequency Analysis / ed. by F. Hlawatsch and F. Auger. — London UK, Hoboken USA : John Wiley &amp; Sons, 2013. — 472 p.</mixed-citation>
     <mixed-citation xml:lang="en">Time-Frequency Analysis / ed. by F. Hlawatsch and F. Auger. — London UK, Hoboken USA : John Wiley &amp; Sons, 2013. — 472 p.</mixed-citation>
    </citation-alternatives>
   </ref>
   <ref id="B29">
    <label>29.</label>
    <citation-alternatives>
     <mixed-citation xml:lang="ru">Yin Z.-F., Zhou X.-Z., Hu Z.-J., et al. Westward Excursion of Pc1/EMIC Waves and Their Source Protons: Paradoxical Observations From Ground and Space // Journal of Geophysical Research: Space Physics. — 2024. — Vol. 129, no. 5. — https://doi.org/10.1029/2023ja032317.</mixed-citation>
     <mixed-citation xml:lang="en">Yin Z.-F., Zhou X.-Z., Hu Z.-J., et al. Westward Excursion of Pc1/EMIC Waves and Their Source Protons: Paradoxical Observations From Ground and Space // Journal of Geophysical Research: Space Physics. — 2024. — Vol. 129, no. 5. — https://doi.org/10.1029/2023ja032317.</mixed-citation>
    </citation-alternatives>
   </ref>
  </ref-list>
 </back>
</article>
