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@PhDThesis{Ferreira:2023:ApTéMa,
               author = "Ferreira, T{\'a}bata Aira",
                title = "Aplica{\c{c}}{\~a}o de t{\'e}cnicas de Machine Learning no 
                         estudo de transientes dos detectores Advanced LIGO",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2023",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2022-12-09",
             keywords = "glitches, LIGO, aprendizado de m{\'a}quina, an{\'a}lise de 
                         redes, ondas gravitacionais, machine learning, network science, 
                         gravitational waves.",
             abstract = "As detec{\c{c}}{\~o}es diretas de ondas gravitacionais n{\~a}o 
                         apenas trouxeram mais uma evid{\^e}ncia da Teoria da Relatividade 
                         Geral de Einstein, mas inauguraram uma nova astronomia. Os 
                         observat{\'o}rios LIGO foram os pioneiros na detec{\c{c}}{\~a}o 
                         desse tipo de sinal e dezenas de eventos j{\'a} foram 
                         catalogados. O n{\'u}mero progressivo de detec{\c{c}}{\~o}es 
                         fomenta a {\'a}rea e gera expectativas em diferentes 
                         observat{\'o}rios e cientistas ao redor do mundo. Entretanto, 
                         n{\~a}o s{\~a}o apenas os sinais de eventos 
                         astrof{\'{\i}}sicos que aparecem nos dados destes detectores, 
                         mas diferentes ru{\'{\i}}dos transientes oriundos de diversos 
                         fatores ambientais, instrumentais ou antropog{\^e}nicos. Estudar 
                         esses invasores locais, usualmente denominados glitches, {\'e} 
                         sempre um desafio para a colabora{\c{c}}{\~a}o 
                         cient{\'{\i}}fica, pois alguns deles t{\^e}m alta taxa de 
                         ocorr{\^e}ncia, podem mimetizar ondas gravitacionais, poluir os 
                         dados e diminuir a signific{\^a}ncia estat{\'{\i}}stica de um 
                         sinal astrof{\'{\i}}sico real. Infelizmente, alguns desses 
                         transientes n{\~a}o t{\^e}m causas identificadas ou definidas, e 
                         a tentativa de buscar tais ind{\'{\i}}cios incentivou este 
                         trabalho. Esta tese apresenta uma forma alternativa para 
                         caracterizar e encontrar classes de glitches no canal 
                         gravitacional, a partir dos denominados glitchgramas. Duas 
                         t{\'e}cnicas computacionais foram utilizadas para avaliar a 
                         efici{\^e}ncia dessa caracteriza{\c{c}}{\~a}o proposta. A 
                         primeira aplicou ferramentas de An{\'a}lise de Redes e a segunda, 
                         de Aprendizado de M{\'a}quina; ambos resultados foram comparados 
                         com as classifica{\c{c}}{\~o}es pr{\'e}vias do Gravity Spy, 
                         ferramenta utilizada pela colabora{\c{c}}{\~a}o para classificar 
                         transientes. A an{\'a}lise de redes obteve resultados excelentes 
                         para determinadas classes, mas nem tanto para outras e, portanto, 
                         limita{\c{c}}{\~o}es no uso dessa t{\'e}cnica a partir de 
                         glitchgramas foram encontradas. No geral, o m{\'e}todo teve 75, 
                         03% de concord{\^a}ncia com Gravity Spy e, com o cosseno de 
                         similaridade, apresentado na t{\'e}cnica, foi poss{\'{\i}}vel 
                         atribuir classes a glitches desconhecidos. O segundo m{\'e}todo 
                         foi efetivo na busca de todas as classes investigadas. Com a 
                         aplica{\c{c}}{\~a}o de uma ferramenta do aprendizado de 
                         m{\'a}quina supervisionado, uma valida{\c{c}}{\~a}o cruzada foi 
                         realizada e o m{\'e}todo concordou em 94, 70% com o Gravity Spy. 
                         Valor que poderia ter sido maior, pois o m{\'e}todo apontou erros 
                         de classifica{\c{c}}{\~a}o do atual modo de an{\'a}lise do 
                         LIGO. O aprendizado de m{\'a}quina ainda mostrou-se independente, 
                         p{\^o}de ser aplicado em an{\'a}lises di{\'a}rias de 
                         funcionamento do LIGO, em busca da presen{\c{c}}a de classes em 
                         canais auxiliares, abriu campos para diferentes 
                         aplica{\c{c}}{\~o}es e permitiu concluir que os glitchgramas 
                         caracterizam bem os glitches. Para exemplificar isso, esta tese 
                         tamb{\'e}m apresenta um estudo das duas classes mais presentes 
                         durante a terceira corrida observacional do LIGO: a Scattered 
                         Light e a Fast Scattering. Para esta {\'u}ltima, uma 
                         investiga{\c{c}}{\~a}o sobre sua rela{\c{c}}{\~a}o com 
                         movimentos micross{\'{\i}}smicos e antropol{\'o}gicos foi 
                         realizada. ABSTRACT: The gravitational wave detections not only 
                         provided further evidence for Einsteins Theory of General 
                         Relativity but also inaugurated a new astronomy. LIGO 
                         observatories were pioneers in detecting such types of signals, 
                         and dozens of events have already been cataloged. The progressive 
                         number of detections has been promoting the area and generating 
                         expectations in scientists worldwide. However, it is not only the 
                         signals of astrophysical events that appear in the data of these 
                         detectors, different transient noise sources arise from various 
                         environmental, instrumental, or anthropogenic factors. Studying 
                         these local invaders, generally called glitches, is always a 
                         challenge faced by the scientific collaboration, as some of them 
                         have a high occurrence rate, may mimic gravitational waves, 
                         pollute the data and decrease the overall statistical significance 
                         of a real astrophysical signal. Unfortunately, some of these 
                         transients do not have identified or present well-defined reasons, 
                         and the attempt to look for such indications encouraged this work. 
                         This dissertation presents an alternative way to characterize and 
                         find classes of glitches in the gravitational channel, based on 
                         the so-called glitchgrams. Two computational techniques were used 
                         to evaluate the efficiency of this proposed characterization. The 
                         first applied Network Analysis tools and the second Machine 
                         Learning tools; both results were compared with previous Gravity 
                         Spy classifications, the tool used by the collaboration to 
                         categorize transients. Network Science obtained excellent results 
                         for some classes but not so much for others; therefore, 
                         limitations in using this technique from glitchgrams were found. 
                         Overall, the method had 75.03% of agreement with Gravity Spy, and, 
                         with the cosine of similarity, presented in the method, it was 
                         possible to assign classes to unknown glitches. The second method 
                         was effective in searching all investigated categories. With a 
                         supervised machine learning tool, cross-validation was performed, 
                         and the technique agreed at 94.70% with Gravity Spy. The value 
                         could have been higher, as the method pointed out classification 
                         errors in the current LIGO analysis mode. Machine learning still 
                         proved to be independent, could be applied in daily analyzes of 
                         LIGOs operation, in search of the presence of classes in auxiliary 
                         channels, opened fields for different applications, and allowed 
                         concluding that glitchgrams characterize well glitches. In order 
                         to exemplify this, this dissertation also studies the two most 
                         common classes during the third LIGO observational run: the 
                         Scattered Light and the Fast Scattering. For the latter, an 
                         investigation into its relationship with microseismic and 
                         anthropological motions was performed.",
            committee = "Aguiar, Odylio Denys de (presidente) and Costa, C{\'e}sar Augusto 
                         (orientador) and Tinto, Massimo and Jablonski, Francisco Jos{\'e} 
                         and Lenzi, C{\'e}sar Henrique and Tosta e Melo, Iara",
         englishtitle = "Application of Machine Learning techniques in the study of 
                         transients from Advanced LIGO detectors",
             language = "pt",
                pages = "120",
                  ibi = "8JMKD3MGP3W34T/48AFMK5",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34T/48AFMK5",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 abr. 2024"
}


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