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    <responseDate>2026-10-14T12:03:58Z</responseDate>
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    <identifier>10.57760/sciencedb.30888</identifier>
    <datestamp>2026-03-20T09:55:04Z</datestamp>
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  <dc:date>2026-03-20</dc:date>
  <dc:title>Low-altitude economy term frequency</dc:title>
  <dc:identifier>doi:10.57760/sciencedb.30888</dc:identifier>
  <dc:language>en</dc:language>
  <dc:description>Use Python and Jieba word segmentation tool to process TXT format annual report text. Combining the Implementation of Innovative Applications in General Aviation Equipment&amp;nbsp;The policy document &amp;quot;Plan (2024-2030)&amp;quot; includes the construction of low altitude, airspace, unmanned aerial vehicles eVTOL、 Vertical takeoff and landing&amp;nbsp;A low altitude economic dictionary with 12 keywords: aviation, airport, remote sensing technology, avionics, satellite, navigation, and Beidou. Translate this word into English&amp;nbsp;Import Jieba's proprietary dictionary module into the dictionary, perform word segmentation and frequency statistics on the text of enterprise annual reports, and calculate the above relationships for each company&amp;nbsp;The total frequency of occurrence of key words.&amp;nbsp;It should be noted that although the word frequency statistics can be traced back to 2014. However, in data cleaning, due to a large number of missing key variables before 2018, forcibly including early samples will result in serious sample loss and cannot form a balanced panel. To ensure the completeness of the regression samples and the comparability of the estimation results, this study will ultimately set the research window uniformly to 690 A-share listed companies with the best data conditions from 2019 to 2023.&amp;nbsp;</dc:description>
  <dc:subject>low-altitude economy; aviation; Jieba</dc:subject>
  <dc:creator>Li Dingzhao</dc:creator>
  <dc:rights>PUBLIC</dc:rights>
  <dc:rights>https://creativecommons.org/licenses/by/4.0/</dc:rights>
  <dc:type>dataset</dc:type>
  <dc:publisher>Science Data Bank</dc:publisher>
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