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@MastersThesis{Almeida:2021:EsCaAm,
               author = "Almeida, Adriano Pereira",
                title = "Uso de redes neurais para previs{\~a}o de descargas 
                         el{\'e}tricas nuvem-solo a partir de dados de radar: um estudo de 
                         caso na Amaz{\^o}nia",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2021",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2021-05-28",
             keywords = "tempestades severas, raios, RADAR, an{\'a}lise explorat{\'o}ria 
                         de dados, intelig{\^e}ncia artificial, severe storms, lightnings, 
                         exploratory data analysis, artificial intelligence.",
             abstract = "A regi{\~a}o central da Bacia Amaz{\^o}nica {\'e} caracterizada 
                         por ter uma vegeta{\c{c}}{\~a}o densa e condi{\c{c}}{\~o}es 
                         atmosf{\'e}ricas favor{\'a}veis para o desenvolvimento de 
                         tempestades severas e com alta incid{\^e}ncia de raios. Diante 
                         disso, foi desenvolvido neste trabalho um estudo de algumas 
                         parametriza{\c{c}}{\~o}es atrav{\'e}s de t{\'e}cnicas de 
                         aprendizado de m{\'a}quina para prover subs{\'{\i}}dios para o 
                         desenvolvimento de sistemas de previs{\~a}o de descargas 
                         el{\'e}tricas a curto prazo, levando em considera{\c{c}}{\~a}o 
                         as condi{\c{c}}{\~o}es locais dessa regi{\~a}o. Essas 
                         parametriza{\c{c}}{\~o}es partiram de conclus{\~o}es obtidas na 
                         an{\'a}lise explorat{\'o}ria dos dados de radar 
                         meteorol{\'o}gico e da sele{\c{c}}{\~a}o de vari{\'a}veis por 
                         meio de classifica{\c{c}}{\~o}es com a {\'a}rvore de 
                         decis{\~a}o. Al{\'e}m disso, foram criados modelos baseados na 
                         rede neural perceptron multicamadas (MLP) com diversas 
                         configura{\c{c}}{\~o}es de entrada e varia{\c{c}}{\~o}es dos 
                         seus principais hiper-par{\^a}metros, que tiveram como intuito 
                         avaliar a sensibilidade das vari{\'a}veis em diferentes 
                         intervalos de tempos anteriores {\`a} previs{\~a}o. As 
                         previs{\~o}es foram feitas para 12 minutos {\`a} frente, 
                         utilizando os valores das vari{\'a}veis em instantes anteriores 
                         {\`a} previs{\~a}o: t-1 (12 minutos); t-2 (24 minutos); e t-3 
                         (36 minutos). Embora a maioria das vari{\'a}veis 
                         meteorol{\'o}gicas utilizadas possuam depend{\^e}ncias temporais 
                         mais restritas, os modelos que utilizaram os tr{\^e}s instantes 
                         de tempo, tiveram melhor desempenho. Junto com a 
                         degrada{\c{c}}{\~a}o dos dados de entrada e 
                         informa{\c{c}}{\~o}es sobre as caracter{\'{\i}}sticas dos 
                         perfis de refletividade radar foi poss{\'{\i}}vel definir 
                         crit{\'e}rios que podem ajudar na melhorias das previs{\~o}es de 
                         raios via redes neurais. ABTSRACT: Lightning associated with 
                         severe storms can cause several socio-economic problems. Due to 
                         its high convective activity, predominantly equatorial location, 
                         and large territorial extension, Brazil is one of the countries 
                         where the highest incidence of lightning strikes occurs globally. 
                         Studies show that the most significant cause of human fatalities 
                         related to storms in Brazil is associated with lightning and that 
                         a large part of them appear in rural areas. The material damages 
                         caused by these events are also very recurrent. Therefore, the 
                         interest in creating forecasting systems for this natural event is 
                         of paramount importance. However, several challenges are 
                         associated with the creation of lightning forecasting systems. 
                         Sometimes these challenges are related to the characteristics of 
                         the event itself, such as its high variability and its 
                         relationship with complex physical processes that are difficult to 
                         model computationally. The local factors that can influence the 
                         development of electrically active storms should also be 
                         considered. The central region of the Amazon Basin is 
                         characterized by dense vegetation and favorable atmospheric 
                         conditions for the development of severe storms and a high 
                         incidence of lightning. Therefore, a study of some 
                         parameterizations through machine learning techniques was 
                         developed in this work to provide subsidies for the development of 
                         lightning forecasting lightning in the short-term systems, 
                         considering the local conditions of the central region of the 
                         Amazon Basin. These parameterizations started from conclusions 
                         obtained in the exploratory analysis of meteorological radar data 
                         and the selection of variables through classifications with the 
                         decision tree. In addition, models based on the neural network 
                         multilayer layer perceptron (MLP) with different input 
                         configurations were created to evaluate the sensitivity of the 
                         variables at different time intervals before the forecast. The 
                         forecasts were made for 12 minutes ahead, using the previous times 
                         values of the variables: t-1 (12 minutes); t-2 (24 minutes); and 
                         t-3 (36 minutes). Although most meteorological variables used have 
                         more restricted temporal dependencies, the models that used three 
                         previous time instants performed better. Along with the 
                         degradation of the input data and information on the 
                         characteristics of the radar reflectivity profiles, it was 
                         possible to define criteria that can help to improve the lightning 
                         forecasts via neural networks.",
            committee = "Santos, Rafael Duarte Coelho (presidente) and Calheiros, Alan 
                         James Peixoto (orientador) and Shiguemori, Elcio Hideiti and 
                         Rodriguez, Carlos Augusto Morales",
         englishtitle = "Use of neural networks to predict cloud-to-ground lightning from 
                         radar data: a case study in the Amazon",
             language = "pt",
                pages = "208",
                  ibi = "8JMKD3MGP3W34R/44JMNDL",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34R/44JMNDL",
           targetfile = "publicacao.pdf",
        urlaccessdate = "26 abr. 2024"
}


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