2,203 research outputs found

    Formal city vs informal city: from the clandestine neighbourhoods to the concept of UAIG (urban areas of illegal genesis)

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    Over time, the definitions of formal and informal city have been changed or acquired different meanings in the various fields of human activity. Since the 1950s, the industrialisation and changes in rural practices caused an accelerating mass migration of people from rural areas to major cities, which gave rise to numerous informal settlements on the peripheries of the cities. A large rural migration flows to cities searching for better living conditions. The main goal of this paper is to present the transformations that have occurred in the territory, with a focus on the peripheries of the city of Lisbon with the constructions of clandestine neighbourhoods, demonstrating through a mapping, the evolution of these informal territories in the formal city, to assess how the UAIG (Urban Areas of Illegal Genesis) developed and influenced the transformations and visions of the formal city, and the relationship that people have with the place they inhabit.info:eu-repo/semantics/acceptedVersio

    UAIG (Urban Areas of Illegal Genesis) - (re) living to (re) integrate

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    This ongoing research intends to develop a strategy for the (re) qualification of the public space in the UAIG (Urban Areas of Illegal Genesis), through the introduction of an intervention methodology – collaborative participatory processes. The strategies of intervention in the public space have launched new challenges to research in architecture. In a demanding society with strong participatory and collaborative citizenship, public space increasingly assumes an important role in urban practices. The lack of public space in areas of illegal genesis in Metropolitan Area of Lisbon (MLA), shaped the PhD research question: How public space make UAIG ́s (re) living to (re) integrate it in Lisbon Metropolitan Area dynamics? Participation means the collaboration of people pursuing objectives that they themselves have defined. A public space is one which, in its design and in its use, stimulates a sense of belonging to a wider community beyond the bounds of the strictly private sphere. It is, then, a scenario that fosters contract between difference people mixing uses and meeting place for individual and collective interests. The answer is to adopt methods and instruments that allow the creation of a methodology for the analysis of a great transversality of scales – territory, neighbourhoods and public space. This research aims to contribute to a generic model of good practices applicable to any process of requalification of the urban space of the UAIG.info:eu-repo/semantics/acceptedVersio

    O modelo de competência nos jogos de invasão aplicado ao ensino do jogo de futebol em contexto de clube/escola

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    A incongruência entre as características do modelo de ensino tradicionalmente mais utilizado no ensino/treino dos jogos desportivos e as teorias recentes da aprendizagem tem impulsionado o desenvolvimento de múltiplos modelos alternativos. Estes modelos têm em comum o facto de: a) enfatizarem a compreensão do jogo como condição para o desenvolvimento das aprendizagens; b) subordinarem a aprendizagem das habilidades técnicas à necessidade de as aplicar no jogo; c) valorizarem a satisfação, o gozo e a motivação dos praticantes; e) cuidarem das relações de comunicação e cooperação no seio das equipas. O modelo de competência nos jogos de invasão é um dos modelos alternativos que, pela forma simples como articula os conteúdos, tem vindo a conquistar adeptos entre professores e treinadores. Neste trabalho apresentamos uma proposta de aplicação do modelo de competência nos jogos de invasão ao ensino do futebol em contexto de clube

    Turing machines can be efficiently simulated by the General Purpose Analog Computer

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    The Church-Turing thesis states that any sufficiently powerful computational model which captures the notion of algorithm is computationally equivalent to the Turing machine. This equivalence usually holds both at a computability level and at a computational complexity level modulo polynomial reductions. However, the situation is less clear in what concerns models of computation using real numbers, and no analog of the Church-Turing thesis exists for this case. Recently it was shown that some models of computation with real numbers were equivalent from a computability perspective. In particular it was shown that Shannon's General Purpose Analog Computer (GPAC) is equivalent to Computable Analysis. However, little is known about what happens at a computational complexity level. In this paper we shed some light on the connections between this two models, from a computational complexity level, by showing that, modulo polynomial reductions, computations of Turing machines can be simulated by GPACs, without the need of using more (space) resources than those used in the original Turing computation, as long as we are talking about bounded computations. In other words, computations done by the GPAC are as space-efficient as computations done in the context of Computable Analysis

    Leaf litter processing in low order streams

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    Forests produce a large amount of detritus, that inevitably end up in streams, subsidizing aquatic systems with organic matter and nutrients. Here we review some of the research carried out at the University of Coimbra with the objective of getting a better understanding of the breakdown process of these materials and its incorporation to secondary production. Litter-fall in deciduous forests in Central Portugal can reach up to 750 g AFDM of leaves m-2 yr-1, with 73% of the litter produced between October and December. In several retention experiments, we measured a 90% leaf retention in low order (1st- 4th) streams within 15 - 70 m, and a standing stock of up to 450 g AFDM m-2. The amount of nutrients in the water and the plant physical and chemical defenses can be an indicator of the rate at which plant material is incorporated into secondary production or exported as dissolved and fine particles of organic matter. Respiration rates of decomposing leaves incubated with fungicides were severely reduced, supporting the idea that fungi are very important agents in litter breakdown. The fungi group known as aquatic hyphomycetes are capable of producing enzymes able to cause leaf maceration, and by 2 to 3 weeks, up to 15 % of the decomposing leaf biomass corresponds to fungi. Shredder invertebrates are also biological agents involved in litter breakdown. Given their densities and feeding rates, we measured consumption rates of 12 - 54 g of leaves m-2 yr-1 in a stream in Central Portugal, corresponding to 2 to 9 times the litter standing stock. Feeding rates were high in nutrient rich leaves and low in chemical and physically protected leaves with low nutrient content. According to several experiments, fungal colonization facilitates the access of invertebrates to the energy trapped in deciduous leaves in streams. Some invertebrates have strategies to cope with low quality food (leaves with low microbial biomass or high chemical defenses). Those include high mobility, small size, compartmentalized digestion in the gut, presence of endosymbionts, and the capability to decrease respiration rates. The relative importance of fungi and invertebrates in the incorporation of plant litter material into secondary production varies across rivers and biomes. Shredder invertebrates seem to play a key role in litter breakdown in headwaters, but their importance appears to decrease downstream. In the same way, some systems where leaves are hard or protected, shredder invertebrates may be less abundant and the energy may be mainly recovered from litter by fungi. Eucalyptus plantations are systems with low diversity of invertebrates and aquatic hyphomycetes. Streams running through eucalyptus plantations seem therefore ideal to experimentally investigate relationships between structural parameters (biodiversity) and function. Finally, our research has been extended to other climatic areas including the Mediterranean and tropical streams. We reported a wide variety of situation in those systems. A general rule applying to all of them is that if leaf litter is abundant and high quality, the incorporation of energy into detrital food webs can be processed very quickly. However, if leaves are well protected and nutrients in the water are low, processing rates are equally very low, independently of the ambient temperatures.Los bosques producen una gran cantidad de detritus orgánicos, que inevitablemente llegan a los ríos, subsidiando los sistemas acuáticos con materiales y nutrientes. Aquí se revisan algunos de los trabajos que se han hecho en la Universidad de Coimbra con el objetivo de entender mejor el proceso de descomposición de este material y su incorporación en producción secundaria. La entrada de hojarasca en bosques caducifolios del Centro de Portugal puede alcanzar hasta 750 g PSLC (peso seco libre de cenizas) m-2 año-1, con 73 % de este valor ocurriendo entre Octubre y Diciembre. En varios experimentos de retención medimos que cerca de 90 % hojas que entran en ríos de baja orden (1ª- 4ª) eran retenidas entre los 15 y 75 m, y que la biomasa de hojarasca acumulada era de hasta 450 g PSLC m-2. La cantidad de nutrientes en el agua y las defensas físicas y químicas de las plantas pueden ser un indicador de la tasa a que el material orgánico es incorporado en producción secundaria o exportado como material disuelto o finamente particulado. Las tasas de respiración de hojas incubadas con fungicidas disminuyeron severamente apoyando la idea de que los hongos son agentes muy importantes en la descomposición de hojarasca el los ríos. El grupo de hongos conocido como hifomicetos acuáticos producen enzimas que causan la maceración de hojas, y en 2 o 3 semanas, hasta 15 % de la biomasa de una hoja en descomposición puede corresponder a hongos. Los invertebrados desmenuzadores son también agentes biológicos en la descomposición. Dadas las densidades de desmenuzadores y sus tasas de ingestión de alimento, hemos calculado tasas de consumo de hojas en ríos de12 - 54 g m-2 año-1, lo que corresponde a 2 a 9 veces la cantidad de hojarasca presente. Las tasas de consumo son generalmente altas en substratos ricos en nutrientes y bajas en hojas pobres en nutrientes o protegidas del punto de vista químico y físico. De acuerdo varios experimentos, la colonización por hongos facilita el acceso de los invertebrados a la energía de las hojas. Algunos invertebrados han desarrollado estrategias para poder vencer la baja calidad de las hojas, incluyendo un alta movilidad, tamaño pequeño, compartimentalización de la digestión en el intestino, presencia de endosimbiontes y la capacidad para disminuir las tasas respiratorias. La importancia relativa de los hongos e invertebrados en la incorporación de la hojarasca en producción secundaria es variable entre ríos y biomas. Los invertebrados desmenuzadores parecen jugar un papel importante en la descomposición de hojarasca en los ríos de bajo orden, pero su importancia parece disminuir rió abajo. Del mismo modo, en algunos sistemas en que las hojas son duras o protegidas, los invertebrados pueden ser menos abundantes y la energía canalizada en producción secundaria principalmente por los hongos. Las plantaciones de eucaliptos son sistemas con una baja diversidad de invertebrados e hifomicetos acuáticos. Los ríos que corren por plantaciones de eucaliptos parecen ser por este motivo sistemas ideales para investigar las relaciones entre parámetros estructurales (biodiversidad) y función. Finalmente, nuestra investigación ha sido extendida para otras zonas climáticas, incluyendo el Mediterráneo y las zonas tropicales. Hemos reportado una gran variedad de situaciones en esos sistemas. Una regla general a todos ellos es que si la hojarasca es abundante y de alta calidad, la incorporación de la energía de las hojas en las cadenas alimentares se procesa de forma muy rápida. Sin embargo, si las hojas están bien protegidas y los nutrientes el agua son bajos, estas tasas son igualmente muy bajas, independientemente de las temperaturas ambientales

    O ensino do jogo de futebol: um modelo híbrido de desenvolvimento da competência táctica

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    A incongruência entre as caraterísticas dos modelos de ensino tradicionais e as teorias mais recentes do ensino e da aprendizagem tem impulsionado investigadores e treinadores desportivos a desenvolver novos modelos de ensino, dos quais se destacam: Sport Education, Teaching Games for Understanding, Modelo de Competência nos Jogos de Invasão, Escola da Bola e Play Practice. A disseminação extensiva destes modelos de ensino ainda está longe de se verificar tanto nas escolas como nos clubes. No entanto, para que as ideias inovadoras dos modelos se afirmem, muitos caminhos há ainda a percorrer. Um deles parece ser a combinação de modelos e o alargamento do seu campo de aplicação à variedade de jogos desportivos. O presente trabalho tem por objetivo apresentar uma proposta de instrução híbrida, concebida a partir dos modelos de Educação Desportiva e de Competência nos Jogos de Invasão, direcionada para o ensino do jogo de futebol em contexto de escola de futebol. A proposta em análise: comunga do mesmo núcleo de preocupações dos modelos que lhe deram origem (o jogo como um espaço de problemas, a importância da compreensão, da tomada de decisão e da consciência tática, o atleta como construtor ativo da sua aprendizagem); assenta na conceção de que a aprendizagem do jogo formal (11x11) se processa por aproximação gradual através do encadeamento de formas mais simples de jogo - as designadas formas básicas de jogo (FBJ); visa o desenvolvimento da competência tática dos praticantes; está organizada em cinco etapas (construção do jogo a 3, a 5, a 7, a 9, a 11). Os conteúdos de ensino explícito são, em todas as etapas, os princípios do jogo: os princípios fundamentais (penetração, cobertura ofensiva, mobilidade, espaço, contenção, cobertura defensiva, equilíbrio e concentração) e os princípios específicos de organização coletiva definidores do modelo de jogo que se pretende ver jogado. O desenvolvimento da competência tática dos jogadores em cada etapa faz-se através da articulação coerente de três tipos de exercitação de complexidade e abrangência diferentes: a FBJ, as formas parciais de jogo (FPJ) e as tarefas baseadas no jogo (TBJ). O conteúdo explícito da instrução centrada na resolução de problemas do jogo, incide sobre: a definição dos objetivos e resultados a atingir; a identificação/clarificação de princípios e regras de ação; a adequação das ações tático-técnicas aos contextos de jogo. Privilegia-se o questionamento e a descoberta guiada. A avaliação das aprendizagens está alinhada com os objetivos e os conteúdos de ensino. É realizada nas FBJ e FPJ através do recurso a instrumentos flexíveis com duas dimensões de análise (tomada de decisão e eficácia motora) e oito categorias (os princípios fundamentais do jogo)

    USE OF UAV PLATFORM AS AN AUTONOMOUS TOOL FOR ESTIMATING EXPANSION ON INVADED AGRICULTURAL LAND

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    For a long time, in many countries, questions involving disputes about land ownership has generated demand for geoinformation and documentation. In most cases, access for researchers is restricted or humanely impossible by eminence of conflicts, even armed. In these cases, researchers use Remote Sensing and Photogrammetry to enable their studies. However, the dynamics of the phenomenon being studied often requires approaches that traditional techniques become unviable or unable to fulfil. This work shows the results of an approach that used a photogrammetric UAV platform to take pictures of an invaded rural area in Brazil and estimate its expansion over two years. From the taken images, mosaics were generated and then classified using Decision Tree to identify tents. Then it was developed a Matlab algorithm, to detect and quantify the tents on the classified Images. It was possible to infer that there was an expansion of 7.3% between the two analyzed dates and probably more than three thousand people occupied the invasion site

    Age and growth of the Atlantic chub mackerel Scomber colias Gmelin, 1789 off Madeira Island

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    The Atlantic chub mackerel, Scomber colias Gmelin, 1789, is one of the main fisheries resources of Madeira Island. It is caught by a small and coastal purse-seine fleet that traditionally operates around the island. From January 2002 to December 2003, monthly samples of chub mackerel were collected from landings by this commercial fishing fleet. A total of 2212 sagitta otoliths were extracted for age readings from 1068 males (17.4-41.7 cm total length, TL), 1066 females (18.0-41.2 cm TL) and 78 undetermined (13.0-26.8 cm TL). A single reader aged the fishes using surface-read whole otoliths aiming to build annual age-length keys. Age readings precision and reader consistency were assessed by using the average percentage error index (APE ≤ 1.52). Ages were validated up to 4 years using marginal analyses. Estimated mean lengths at age and length von Bertalanffy growth curve parameters, estimated by non-linear methods, showed no significant differences (p>0.05) between sexes (L∞=50.08 cm TL, k=0.252 yr-1 and t0=-1.339 yr; males and females combined). Length-weight relationships were estimated aiming to convert growth in length to growth in weight. No differences between sexes were found in length-weight parameters (P>0.05). For sexes combined, total weight (TW, g) = 0.00218.LT 3.40 and the estimated asymptotic weight, W∞=1523.7 g
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