101 research outputs found

    Exploratory Cluster Analysis from Ubiquitous Data Streams using Self-Organizing Maps

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    This thesis addresses the use of Self-Organizing Maps (SOM) for exploratory cluster analysis over ubiquitous data streams, where two complementary problems arise: first, to generate (local) SOM models over potentially unbounded multi-dimensional non-stationary data streams; second, to extrapolate these capabilities to ubiquitous environments. Towards this problematic, original contributions are made in terms of algorithms and methodologies. Two different methods are proposed regarding the first problem. By focusing on visual knowledge discovery, these methods fill an existing gap in the panorama of current methods for cluster analysis over data streams. Moreover, the original SOM capabilities in performing both clustering of observations and features are transposed to data streams, characterizing these contributions as versatile compared to existing methods, which target an individual clustering problem. Also, additional methodologies that tackle the ubiquitous aspect of data streams are proposed in respect to the second problem, allowing distributed and collaborative learning strategies. Experimental evaluations attest the effectiveness of the proposed methods and realworld applications are exemplified, namely regarding electric consumption data, air quality monitoring networks and financial data, motivating their practical use. This research study is the first to clearly address the use of the SOM towards ubiquitous data streams and opens several other research opportunities in the future

    Manipulating the number of players and targets in team sports : small-sided games during physical education classes

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    This study aimed to examine the effects of players and targets number variation on technical, tactical and physiological indicators in basketball, handball and indoor football. Nine 8th grade students (age 13.3 ± 0.7 years, stature 166.8 ± 3.8 cm, body mass 55.3 ± 4.2 kg) participated in four small-sided games (SSG) for each sport. Despite the differences between the sports, similar average values for technical and tactical indicators were found in both basketball and indoor football SSG. An increase in the number of players affected the duration of unsuccessful offensive phases, the number of passes per offensive phase, successful passes per offensive phase and decreased ball possession per player. Whilst all SSG in this study imposed high physiological demands, 3-a-side games played with one target elicited the greatest responses. In conclusion, the 3-a-side SSG promoted similar technical-tactical indicators and higher physiological demands than 4-a-side SSG.Este estudio tuvo como objetivo examinar los efectos del número de jugadores y metas en la variación de los indicadores técnicos, tácticos y fisiológicos en baloncesto, balonmano y fútbol sala. Nueve estudiantes del octavo grado (edad 13.3 ± 0.7 años, estatura 166.8 ± 3.8 cm, masa corporal 55.3 ± 4.2 kg) participarón en cuatro juegos reducidos (SSG) para cada deporte. A pesar de las diferencias entre los deportes, se encontrarón valores medios similares en los indicadores técnicos y tácticos tanto en los juegos reducidos del baloncesto como en los de fútbol sala. El aumento de los jugadores ha provocado el aumento de la duración de la fase ofensiva sin éxito, número de pases por fase ofensiva, pases acertados por fase ofensiva y ha provocado una disminución de la posesión del balón por jugador. Mientras la totalidad de juegos reducidos utilizados en este estudio han impuesto un elevada demanda fisiológica, los juegos reducidos de 3x3 jugados con una meta provocaron las mayores respuestas. En conclusión, los juegos reducidos de 3x3 ha inducido valores similares en los indicadores técnico-tácticos, pero demandas fisiológicas más altas que los juegos reducidos de 4x4.Este estudo teve como objectivo analisar os efeitos do número de jogadores e dos objectivos na variação dos indicadores técnicos, tácticos e fisiológicos no basquetebol, andebol e futsal. Nove estudantes do oitavo ano (idade 13.3 ± 0.7 anos, estatura 166.8 ± 3.8 cm, massa corporal 55.3 ± 4.2 kg) participaram em quatro jogos reduzidos (SSG) para cada modalidade. Apesar das diferenças entre os desportos, foram verificados valores médios similares nos indicadores técnicos e tácticos nos jogos reduzidos de basquetebol e futsal. O aumento dos jogadores provocou o aumento da duração da fase ofensiva sem êxito, número de passes por fase ofensiva, passes certos por fase ofensiva e provocou uma diminuição da posse de bola por jogador. Enquanto a totalidade de jogos reduzidos utilizados neste estudo implicou uma elevada exigência fisiológica, os jogos reduzidos de 3X3 jogados com um objectivo provocaram as maiores respostas. Em suma, os jogos reduzidos de 3x3 induziram valores similares nos indicadores técnico-tácticos, mas exigências fisiológicas mais elevadas que os jogos reduzidos de 4X4

    PREFÁCIO

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    Apresentação Dossiê “O Urbanismo e Porto Alegre”   No Brasil, o emprego da palavra Urbanismo é problemático. Ela abriga diferentes significados, sempre associados a diferentes formas de ação sobre a cidade. Afinal, o Urbanismo trata do desenho arquitetônico da cidade? Ou do planejamento e gestão do uso do solo urbano? É um domínio profissional exclusivo de arquitetos e urbanistas? Ou um espaço de convergência de múltiplas profissões? Em Porto Alegre, o Urbanismo é campo de saberes e fazeres que foi se afirmando ao longo dos séculos XIX e XX a partir de iniciativas as mais diversas. São célebres as experiências iniciadas nos ambientes que tiveram: juízes régios atuando no ordenamento urbano da Porto Alegre colonial, Código de Postura Municipal de construções de 1897,  Plano Geral de Melhoramentos de 1914,   Planos Diretores de 1958 e 1979, Plano Diretor de Desenvolvimento Urbano e Ambiental de 1999; Personagens como Otávio Rocha, Edvaldo Pereira Paiva, Luiz Arthur Ubatuba de Farias, Demétrio Ribeiro; O curso de Urbanismo, oferecido pelo Instituto de Belas Artes entre 1947 e 1949; dentre diversos artistas e escritores que retrataram a cidade em suas obras. Para marcar a data comemorativa do aniversário de 250 anos da cidade de Porto Alegre, pretendemos, com esta chamada, explorar a construção da cidade, do Urbanismo e do Planejamento Urbano, a partir da experiência porto-alegrense. Os artigos aqui reunidos representam uma pequena amostra da diversidade de abordagens e perspectivas atualmente em debate no campo. Vão desde a historiografia urbana da cidade de Porto Alegre até a exploração de possíveis cenário de planejamento urbano pós-pandemia; da memória de bairros e lugares até a sociabilidade pública. O leitor encontrará, portanto, um amplo rol de temas, pesquisas e reflexões. Esperamos que o presente dossiê contribua com a reflexão e a compreensão dos fenômenos da cidade contemporânea.             Além dos artigos do dossiê, a revista também festeja os demais artigos recebidos pelo edital e que ora são publicados. É uma alegria continuar a trajetória da revista, respeitando as normas do Qualis Periódicos e diretrizes de uma publicação ética.             São os votos dos organizadores do dossiê.   Dr. Miguel Frederico do Espírito Santo Presidente do Instituto Histórico e Geográfico do Rio Grande do Sul   Dr. Bruno Cesar Euphrasio de Mello Me. José Daniel Craidy Simões Organizador do Dossiê “Histórias da Imprensa”   Dr. Antônio Carlos Hohlfeldt Dr. Fábio Kühn Me. Heinrich Hasenack Comissão da Revista   Dr. Gustavo Castagna Machado Dr. José Carlos da Silva Cardozo Belª. Priscila Pereira Pinto Ma. Thais Nunes Feijó Dr. Wagner Silveira Feloniuk Comissão Executiva   Carlos Otaviano Passos Editor-Junio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

    Get PDF
    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
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