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@PhDThesis{CerejaJúnior:2018:FrAdDi,
               author = "Cereja J{\'u}nior, Moacyr Gon{\c{c}}alves",
                title = "Um framework para adapta{\c{c}}{\~a}o din{\^a}mica de software 
                         aplicado a sistemas de segmento solo",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-05-04",
             keywords = "sistemas auto-adapt{\'a}veis, sistemas solo, 
                         computa{\c{c}}{\~a}o aut{\^o}noma, arquiteturas de software, 
                         qualidade de servi{\c{c}}o, self-adaptive systems, space ground 
                         systems, autonomic computing, software architecture, quality of 
                         service (QoS).",
             abstract = "Arquiteturas de sistemas espaciais s{\~a}o compostas de tr{\^e}s 
                         segmentos: espacial, lan{\c{c}}ador e solo. Nos {\'u}ltimos 
                         anos, com refer{\^e}ncia ao segmento espacial, 
                         inova{\c{c}}{\~o}es tecnol{\'o}gicas, como cubesats, t{\^e}m 
                         produzido impactos como a diminui{\c{c}}{\~a}o do tamanho dos 
                         sat{\'e}lites e aumento do volume de objetos no espa{\c{c}}o. 
                         Desta forma, ao inv{\'e}s de adotar grandes sat{\'e}lites nas 
                         miss{\~o}es espaciais, s{\~a}o utilizados 
                         constela{\c{c}}{\~o}es e mega constela{\c{c}}{\~o}es. Esta 
                         altera{\c{c}}{\~a}o arquitetural produz um n{\'u}mero grande de 
                         sat{\'e}lites que devem ser controlados de forma simult{\^a}nea 
                         e o aumento da volumetria de dados que devem ser processados pelos 
                         sistemas de segmento solo. Em virtude deste contexto, foi 
                         realizada neste trabalho uma vasta pesquisa, no campo dos sistemas 
                         de software auto adapt{\'a}veis, apresentados conceitos e um 
                         framework denominado Arctic Fox, que permite um sistema de 
                         Segmento de Solo alterar suas condi{\c{c}}{\~o}es estruturais e 
                         toda a sua din{\^a}mica. Esta adapta{\c{c}}{\~a}o {\'e} 
                         realizada pela implementa{\c{c}}{\~a}o de duas classes de 
                         conhecimento fundamentais o Conhecimento Contextual (Estrutura do 
                         Sistema) e o Conhecimento Situacional (Din{\^a}mica e 
                         Comportamento do Sistema), elementos estes respons{\'a}veis pela 
                         tomada de decis{\~a}o de adapta{\c{c}}{\~a}o. V{\'a}rios 
                         elementos comp{\~o}em este conhecimento como os Componentes de 
                         Sistemas existentes (Servi{\c{c}}os), elementos de hardware e 
                         principalmente as m{\'e}tricas de Qualidade de servi{\c{c}}o. A 
                         utiliza{\c{c}}{\~a}o deste conhecimento {\'e} realizada 
                         atrav{\'e}s do Modelo MAPE-K, que proporciona o monitoramento, a 
                         an{\'a}lise, o planejamento e a execu{\c{c}}{\~a}o das 
                         altera{\c{c}}{\~o}es estruturais e comportamentais do sistema. A 
                         base de conhecimento {\'e} atualizada por elementos 
                         respons{\'a}veis pela aquisi{\c{c}}{\~a}o do conhecimento, que 
                         reflete as inclus{\~o}es e as altera{\c{c}}{\~o}es dos estados 
                         dos elementos que comp{\~o}em a arquitetura do Sistema Solo. De 
                         maneira a avaliar o framework proposto, foi implementado um 
                         prot{\'o}tipo, e um estudo de caso para o EMBRACE. (programa de 
                         Estudo e Monitoramento BRAsileiro de Clima Espacial) do INPE. Os 
                         sistemas de solo do Clima Espacial s{\~a}o respons{\'a}veis pelo 
                         armazenamento, processamento e dissemina{\c{c}}{\~a}o de dados 
                         de diversos tipos de instrumentos. Desta forma, 
                         situa{\c{c}}{\~o}es como a inoper{\^a}ncia de um instrumento, 
                         ou falha em algum servidor, produzem impacto na 
                         opera{\c{c}}{\~a}o regular do Sistema Solo, com 
                         degrada{\c{c}}{\~a}o da qualidade do servi{\c{c}}o prestado 
                         para a miss{\~a}o. No estudo de caso em quest{\~a}o, a 
                         utiliza{\c{c}}{\~a}o do framework {\'e} exercitada e 
                         atrav{\'e}s de um experimento controlado foram analisados os 
                         impactos da auto-adapta{\c{c}}{\~a}o. Utilizando 
                         solicita{\c{c}}{\~o}es de uso de um servi{\c{c}}o 
                         t{\'{\i}}pico do EMBRACE, o Gtex, verificouse ganhos para a 
                         disponibilidade do sistema, via a observa{\c{c}}{\~a}o da Taxa 
                         de Sucesso da chamada ao Servi{\c{c}}o. Desta forma, conclui-se 
                         neste experimento que o uso do framework contribui de forma 
                         significativa para a Qualidade do Sistema. ABSTRACT: Space systems 
                         architectures are composed of three segments: space segment, 
                         ground systems and launchers. The space segment, in recent years 
                         has driven lots of technological innovations, such as cubesats. 
                         These new kinds of technologies produce impacts such as decreasing 
                         of the size of satellites and increasing the amount of objects in 
                         space. Thus, instead of adopting large satellites in space 
                         missions, constellations and mega constellations of very small 
                         satellites are used. These architectural changes produce a large 
                         number of satellites that must be controlled simultaneously and 
                         have their large amount of data processed, most of the time, in 
                         real time by the ground systems. In this work, a vast research of 
                         self-adaptive software systems was carried out, concepts and a 
                         framework called Arctic Fox are presented. Using the framework the 
                         ground systems can have their structural elements and behavior 
                         conditions changed. This adaptation is accomplished by the 
                         implementation of two fundamental knowledge classes that are used 
                         for decision making: Context Awareness (Structural) and 
                         Situational Awareness (Behavior). This knowledge is composed by 
                         several elements such as the existing system components 
                         (services), hardware elements and especially the quality of 
                         service metrics. The use of this knowledge is performed through 
                         the MAPE-K model, which provides the monitoring, analysis, 
                         planning and execution of adaptations in the ground systems. The 
                         knowledge base is updated by elements responsible for the 
                         knowledge acquisition, which reflects the inclusions and the 
                         changes of the elements states that compose the ground System 
                         architecture. In order to evaluate the proposed framework, a 
                         prototype was implemented, and a case study for the Brazilian 
                         Space Weather Program EMBRACE of INPE is conducted. The {"}Space 
                         Weather Systems{"} are responsible for the storage, processing and 
                         data dissemination of different types of instruments. In this way, 
                         situations such as some instrument data provider or server 
                         computers failure, impact the regular ground systems operation, 
                         with degradation of the service quality provided by the mission. 
                         In the stated case study, the use of the framework is exercised 
                         and through a controlled experiment the impacts of self-adaptation 
                         were analyzed. Using services calls and derived {"}success rate{"} 
                         metrics to a typical EMBRACE service, Gtex Service, availability 
                         gains was observed. The experiment demonstrates that the use of 
                         the framework contributes significantly to improve the ground 
                         systems segment quality.",
            committee = "Ferreira, Maur{\'{\i}}cio Gon{\c{c}}alves Vieira (presidente) 
                         and Sant'Anna, Nilson (orientador) and Mattiello Francisco, Maria 
                         de F{\'a}tima and Santos, Walter Abrah{\~a}o dos and Silveira, 
                         F{\'a}bio Fagundes and Arakaki, Reinaldo Gen Ichiro",
         englishtitle = "A framework to provide self-adaptive support to space ground 
                         systems",
             language = "pt",
                pages = "193",
                  ibi = "8JMKD3MGP3W34R/3QRDJ45",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3QRDJ45",
           targetfile = "publicacao.pdf",
        urlaccessdate = "30 nov. 2020"
}


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