925 research outputs found

    Análise cientométrica da atividade científica na área de solos: o caso da América Latina.

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    Os indicadores cientométricos em Ciência e Tecnologia surgem da necessidade mensuração da produção científica, partindo-se da premissa de que a ciência se encontra, em grande parte, incorporada em sua literatura. Sendo assim este estudo se insere nesse contexto, ao utilizar a Cientometria para mapear a produção científica na área de solos, área do conhecimento que tem se destacado devido à sua atuação fundamental na agricultura e, mais recentemente, em temas da agenda global de manejo e uso sustentável dos recursos naturais. O método empregado foi a análise bibliométrica automatizada em registros extraídos da base de dados Scopus, no período de 1999-2010. Os resultados demonstram a importância da disciplina no meio científico, ao comprovar o crescimento do número de artigos publicados, de temas envolvidos, dos principais periódicos e das instituições de pesquisa que se destacam na produção de conhecimento em solo na América Latina.bitstream/item/63701/1/BPD-172-Analise-cientometrica.pd

    Representing Terrain With Mathematical Operators

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    This work describes a mathematical representation of terrain data consisting of a novel operation, the “drill”. It facilitates the representation of legal terrains, capturing the richness of the physics of the terrain’s generation by digging channels in the surface. Given our current reliance on digital map data, hand-held devices, and GPS navigation systems, the accuracy and compactness of terrain data representations are becoming increasingly important. Representing a terrain as a series of operations that can procedurally regenerate the terrains allows for compact representation that retains more information than height fields, TINs, and other popular representations. Our model relies on the hydrography information extracted from the terrain, and so drainage information is retained during encoding. To determine the shape of the drill along each channel in the channel network, a cross section of the channel is extracted, and a quadratic polynomial is fit to it. We extract the drill representation from a mountainous dataset, using a series of parameters (including size and area of influence of the drill, as well as the density of the hydrography data), and present the accuracy calculated using a series of metrics. We demonstrate that the drill operator provides a viable and accurate terrain representation that captures both the terrain shape and the richness of its generation

    Production of annual ryegrass with different doses of nitrogen fertilization in topdressing.

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    Made available in DSpace on 2019-12-30T18:10:48Z (GMT). No. of bitstreams: 1 SeminaCiAgMittelmannProduction.pdf: 363245 bytes, checksum: 39152185b5b3d0a8133d04e3c3e2af64 (MD5) Previous issue date: 2019bitstream/item/207926/1/SeminaCiAg-Mittelmann-Production.pd

    A Presença Francesa No Instituto Nacional De Pesquisas Da Amazônia - Inpa

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    [No abstract available]2112530Ailes, C.P., (1988) New Directions for U.S.- Latin American Cooperation in Science and Technology, , Final Report prepared for National Aeronautics and Space Administration. Arlington, Va: Science and Technology Policy Program. SRI International/Washington. Jun 1988. Technical note STPP-TN-3164-4. SRI project 3164, task II-5Beaver, D., De, B., Rosen, R., Studies in scientific collaboration: Part I. The professional origins of scientific co-authorship (1978) Scientometrics, 1, pp. 65-84Beaver, D., De, B., Rosen, R., Studies in scientific collaboration: Part II. Scientific co-authorship research productivity and visibility in the french scientific elite, 1799-1830 (1978) Scientometrics, 1, pp. 33-49(1992) O INPA No Contexto Do Desenvolvimento Da Região Amazônica, , Jul./1992(1993) O INPA Como Comissão De Alto Nível Constituida Pelo MCT/PR, , Jan./1993Chesnais, F., (1986) Some Notes on Technological Cumulativeness, thé Appropriation of Technology and Technological Progressiveness in Concentrated Market Structures, , Viena, 1986. MimeoDickson, D., (1988) The New Politics of Science, 404p. , Chicago, The University of Chicago PressEhrlich, R.P., Wilson, E., Biodiversity studies: Science and policy (1992) Science, 253, pp. 758-762. , 16 Aug. 1992Frame, J.D., Carpenter, M.P., International research collaboration (1979) Social Studies of Science, 9, pp. 481-497França.(1981): Ministère Des Affaires Étrangères. Ajuste entre o Conselho Nacional de Desenvolvimento Cientìfico e Tecnológico do Brasil e o Instituto de Pesquisa Científica e Técnica de Ultramar da França. Paris,30 de Janeiro de 1981. MIMEOOkubo, Y., (1989) Structure of International Collaboration in Science: Typology of Countries Through Multivariate Techniques Using A Link Indicator, , MimeoOkubo, Y., Miquel, J.F., International cooperation in basic science (1990) Representations of Science and Technology, pp. 124-143. , WEINGART, P.SEHRINGER,R.WINTERHAGER, M. (eds) Centre for Science Studies, University of Bielefeld, Federal Republic of Germany, 1990(1993) Cooperação ORSTOM/INPA Em Biologia Aquática 1980-1993, , Relatório de atividades. Manaus, abril de 1993a. Mimeo(1993) Cooperação ORSTOM/INPA Em Ecologia 1980-1992, , Relatório de atividades. Manaus, abril de 1993b. MimeoStorer, N.W., The international ity of science and the nationality of scientists (1970) International Science Journal, 22, pp. 87-10

    Formação de doutores no Brasil: o esgotamento do modelo vigente frente aos desafios colocados pela emergência do sistema global de ciência.

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    Este artigo discute como a formação de pesquisadores é influenciada pela dinâmica de produção e uso do conhecimento num determinado contexto de aplicação. Desenvolve-se o argumento de que a política de pós-graduação no Brasil, orientada à carreira e ao desempenho acadêmico, como impõe o modelo de avaliação da Capes, não é capaz de atender às novas competências e papéis esperados dos doutores no atual cenário de intensificação das relações e do intercâmbio científico, econômico e cultural no âmbito nacional e, especialmente, internacional.Título em inglês: DOCTORAL EDUCATION IN BRAZIL: THE WEARINESS OF THE CURRENT MODEL IN FACE OF THE CHALLENGES POSED BY THE EMERGENCE OF THE GLOBAL SYSTEM OF SCIENCE

    Responsible innovation and political accountability: genetically modified mosquitoes in Brazil

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    This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this record.In this paper, we analyse the introduction of genetically modified (GM) mosquitoes in Brazil and use this case to probe the notion of Responsible Innovation and its applicability to the development of new public health biotechnologies in the global South. OX513A, a strain of GM Aedes aegypti mosquitoes developed by the British firm Oxitec, has been used experimentally in Brazil since 2009, when it was imported into the country as a promising new tool in the fight against dengue. We discuss the regulatory history of OX513A in Brazil, as well as the forms of ‘community engagement’ that have accompanied the release of transgenic mosquitoes. We argue that the conduct of a scientific research project is only part of a broader effort to localise insect biotechnology in Brazil, an effort that has enjoyed very visible support from political authorities across the country. We conclude by arguing that if the framework of Responsible Innovation is to have purchase on this sort of transnational and multifaceted innovation trajectory, it has to include at its centre a strong notion of political accountability.Research by Javier Lezaun was supported by the European Research Council (ERC) under the European Community’s Seventh Framework Programme [grant number 263447: BioProperty]. Research by Sarah Hartley was supported by the Leverhulme Trust ‘Making Science Public’ programme [grant number RP2011-SP-013]

    Level-of-Detail Triangle Strips for Deforming Meshes

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    Applications such as video games or movies often contain deforming meshes. The most-commonly used representation of these types of meshes consists in dense polygonal models. Such a large amount of geometry can be efficiently managed by applying level-of-detail techniques and specific solutions have been developed in this field. However, these solutions do not offer a high performance in real-time applications. We thus introduce a multiresolution scheme for deforming meshes. It enables us to obtain different approximations over all the frames of an animation. Moreover, we provide an efficient connectivity coding by means of triangle strips as well as a flexible framework adapted to the GPU pipeline. Our approach enables real-time performance and, at the same time, provides accurate approximations

    A progressive refinement approach for the visualisation of implicit surfaces

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    Visualising implicit surfaces with the ray casting method is a slow procedure. The design cycle of a new implicit surface is, therefore, fraught with long latency times as a user must wait for the surface to be rendered before being able to decide what changes should be introduced in the next iteration. In this paper, we present an attempt at reducing the design cycle of an implicit surface modeler by introducing a progressive refinement rendering approach to the visualisation of implicit surfaces. This progressive refinement renderer provides a quick previewing facility. It first displays a low quality estimate of what the final rendering is going to be and, as the computation progresses, increases the quality of this estimate at a steady rate. The progressive refinement algorithm is based on the adaptive subdivision of the viewing frustrum into smaller cells. An estimate for the variation of the implicit function inside each cell is obtained with an affine arithmetic range estimation technique. Overall, we show that our progressive refinement approach not only provides the user with visual feedback as the rendering advances but is also capable of completing the image faster than a conventional implicit surface rendering algorithm based on ray casting

    Towards a natural classification : the taxonomy and evolution of Xanthorrhoea

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    The ability to increase the filler content of paper without significantly sacrificing its mechanical strength is of high interest for papermakers. In this work, three samples of ground calcium carbonate (GCC), differing in size and in brightness, modified with silica via the sol-gel method, were used as fillers in papermaking. Handsheets were produced using a eucalyptus kraft pulp furnish and with a filler amount near 20%. It was found that not only were the strength properties of the handsheets produced with the modified GCCs always significantly better than those obtained with the unmodified GCCs (e.g., the tensile index exhibited improvements of 16 to 20%), but bulk also was increased (by 7 to 13%). Some decreases in the light scattering and opacity values were noted when using the modified GCC, but the brightness was roughly the same. The enhanced fiber-to-filler bonding may be attributed to the hydrogen bonding between the cellulosic fibers and the hydroxyl groups of the silica coating the calcium carbonate particles

    Daily fluctuation in rotifer population abundance in two environments of the upper Paraná River floodplain, Brazil

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    Daily fluctuation of rotifer population abundance was studied in a lake and in a river of the Upper Paraná River floodplain. Samples were collected in the open water for 14 consecutive days, in the high and low water periods. Densities were higher in the lake, chiefly in the low water period. During the studied period, changes in species dominance were observed. Rotifer abundance showed that higher variability occurred during the high water period in both environments. Rotifer abundance showed high variability in the river during the sampling days. In the lake, fluctuation was related to the hydrological periods. Rotifer abundance fluctuations in the lake were influenced by regional factors (fluviometric level); and in the river by local factors (flow). The sampling design pointed out that seasonal samples are necessary to evaluate rotifer abundance in the lake. However, this is not the case in the river where seasonal differences in abundance were not observed
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