953 resultados para radar clutter
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Pós-graduação em Geociências e Meio Ambiente - IGCE
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Investigação pioneira aplicando Radar de Penetração no Solo (GPR) na área da Praia do Atalaia, norte do Brasil, nos permitiu caracterizar, pela primeira vez, fácies e estratigrafia dos depósitos conhecidos informalmente como Sedimentos Pós-Barreiras (Plioceno e mais recente). Esta sucessão sedimentar recobre discordantemente o embasamento miocênico, representado pelas formações Pirabas/Barreiras. Três unidades estratigráficas foram reconhecidas. A Unidade 1, inferior, consiste em um intervalo com 6 m de espessura média dominado por reflexões pobremente definidas e de baixa amplitude, e que intergradam com reflexões de média escala dos tipos tangencial, obliquo e hummocky. A Unidade 2, intermediária, possui cerca de 9 m de espessura e inclui, principalmente, reflexões oblíquas de larga escala, cujas configurações variam de paralela, tangencial, sigmoidal a sigmoidal-complexa. A Unidade 3, superior, corresponde a um intervalo entre 3,5 e 9 m de espessura, sendo dominada por reflexões hummocky, seguidas por reflexões de média escala dos tipos oblíquo, paralelo a sub-paralelo, e em corte-e-preenchimento. A análise da configuração das reflexões internas e geometria das reflexões nos leva a propor que a unidade correspondente aos Sedimentos Pós-Barreiras é mais variável faciologicamente que inicialmente imaginado, incluindo depósitos eólicos (dunas costeiras), bem como depósitos de cordão litorâneo, planície de maré, canal e mangue. Além disto, o mapeamento das três unidades descritas acima é importante para desvendar a complexidade de sedimentação versus erosão durante o Neógeno tardio no norte do Brasil.
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Imagens de radar de abertura sintética (SAR) vem sendo bem mais utilizadas do que antes nas aplicações de geociências em regiões tropicais úmidas. Nesta investigação, uma imagem RADARSAT-1, na banda C, polarização HH adquirida em 1998 foi usada para o mapeamento costeiro e avaliação da cobertura da terra na área de Bragança, norte do Brasil. Imagem do radar aerotransportado GEMS-1000, na banda X, polarização HH, adquirida em 1972 durante o projeto RADAM foi também utilizada para avaliar as variações costeiras ocorridas nas últimas três décadas. A pesquisa tem confirmado a utilidade da imagem RADARSAT-1 para o mapeamento geomorfológico e avaliação da cobertura da terra, particularmente em costas de manguezal de macromaré. Além disso, um novo método para estimar as variações da linha de costa baseado na superposição de vetores extraídos de diferentes imagens SAR, com alta acurácia geométrica, tem mostrado que a planície costeira de Bragança tem estado sujeita a severa erosão responsável pelo recuo de aproximadamente 32 km2 e acreção de 20 km2, resultando em uma perda de área de manguezal de aproximadamente 12 km2. Como perspectiva de aplicação, dados SAR orbitais e aerotransportados provaram ser uma importante fonte de informação tanto para o mapeamento geomorfológico, quando para o monitoramento de modificações costeiras em ambientes tropicais úmidos.
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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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In this work, we analyze a measurement system that will be implanted in a wheels production line, in order to use those wheels for buses and trucks. The measurement device has to be approved according to the MSA study, due to the fact that the mentioned industry is an automobilistic supplier, so that it has to be conform with the ISO/TS 16949 standards. We showed the MSA studies, as well as some concepts for the work understanding. The airlock wheels systematic production is also broached, that is to say, wheels that use airlock tyres, with a better attention given to the rim production, where the device must be implanted. We analyze and assess the data’s acceptance according to the guidelines showed in this study, along with this, improvement proposals are elaborated and their analysis is made, in order to check the obtained results. Finally, we survey the analyzed measurement system, and new studies are suggested, with the intention of improving it
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Estudo sobre a comunicação organizacional e a capacidade de inovar em empresa de pequeno porte. A questão norteadora busca responder se a comunicação organizacional pode fazer avançar e/ou apoiar a inovação em micro e pequenas empresas. O objetivo central é analisar a relação existente entre a inovação e a comunicação organizacional. Aplicou-se o método estudo de caso e a pesquisa documental para interpretação de instrumento diagnóstico denominado “Radar da Inovação” em uma empresa de pequeno porte, localizada no interior de São Paulo. O diagnóstico é realizado com base em dimensões avaliativas que visam verificar a maturidade e o grau de inovação em micro e pequenas empresas. Por meio da avaliação dessas dimensões foi possível construir quadros analíticos e destacar a influência da comunicação organizacional na promoção da inovação. Os resultados apontam que todas as dimensões do “Radar de Inovação” podem melhorar sua performance por meio da comunicação organizacional.
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This paper is a study on corporate communication and the ability to innovate in small businesses. The guiding question seeks to respond whether organizational communication is able to make progress and / or support innovation in micro and small companies, and the main objective is to analyze the relationship between innovation and organizational communication. It was applied the case study method and document research for interpreting a diagnosis instru- ment called “Innovation Radar” in a small business company located in the countryside of São Paulo state. The diagnosis is made based on assessment dimensions aimed at checking the maturity and the degree of innovation in micro and small companies. By evaluating these di- mensions it was possible to build analytical frameworks and highlight the influence of corporate communication in promoting innovation. The results indicate that every dimension of the “In- novation Radar” can improve their performance by means of corporate communication.
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A climatological characterization of storm properties during two summer seasons, viz. 1998-1999 and 1999-2000, based on observations from the Bauru S-band Doppler radar, was obtained from the TITAN Software of the National Center for Atmospheric Research (Boulder, Co), implemented at IPMet. Parameters, such as mean volume, mean area, mean and maximum echo tops, mean and maximum reflectivity, as well as speed and direction of precipitating systems were determined using the reflectivity >25, 30 and 40 dBZ and a volume >30 km3 as thresholds for storm identification. For the first time, the spatial distributions of these parameters were determined in the central State of São Paulo, based on radar observations. It was found that some preferential areas, where most of the convective activity was concentrated during the study period, were located along the Tietê River. The mean maximum reflectivity field has highlighted preferential regions for convection to develop over the metropolitan area of Campinas, which in turn was reinforced by the distribution of the echo tops and reflectivity >40 dBZ.
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In this article we present some results of ground-penetrating radar (GPR) studies carried out at the Lapa do Santo archaeological site. This cave is within the Lagoa Santa karstic region, Minas Gerais State, Brazil. Results from 44 GPR profiles obtained with 400 MHz shielded antennas indicated anomalous hyperbolic reflections and areas with high sub-horizontal reflection amplitude suggesting archaeological and geological potential targets, respectively. These results were encouraging and were used to guide excavations at this site. Excavation of test units (metre by metre) allowed identifying an anthropogenic feature, e.g., a fire hearth structure and natural features, such as a stalagmite and top of bedrock. Results also indicated the importance of the GPR survey as a tool for orienting archaeological researches, increasing the probability of finding archaeological interest targets in an excavation program in an area of environmental protection.
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Through-wall imaging (TWI) may provide vital information on interior environment in cases when physically entering such environment would pose danger to the person involved. The concept of ultra wideband radar (UWB radar) is an emerging technology, which offers high spatial resolution, as opposed to narrow band radars. Thus, TWI applications using UWB radar have become a growing field of research with several applications in the civil and defense areas such as rescue and surveillance. For this study, a prototype system of UWB radar to TWI has been built. Analyses and result to several kinds of experiments have been presented, that is, detection and visualization of metallic targets behind wooden board wall and concrete blocks wall. The results are encouraging and show the advantages of using UWB radar for TWI. (C) 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:339-344, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26543
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Paleoenvironmental interpretation of proxy data derived from peatlands is largely based upon an evolutionary model for ombrotrophic bogs, in which peat accumulates in still environments. Reports on proxies obtained from minerotrophic fens, where hydrologic inputs are variable, are less common. In this study, a highland peatland in southern Brazil is presented through ground penetrating radar (GPR) and sedimentological, palynological and geochronologic data. The radar stratigraphic interpretation suggests a relatively complex history of erosion and deposition at the site since the beginning of Marine Isotope Stage 3 (MIS 3) interstadial period. In spite of this, radar stratigraphic and palynologic interpretations converge. Electromagnetic reflections tend to group in clusters that show lateral coherence and correlate with different sediment types, while pollen grains abound and are well preserved. As a result, the study of minerotrophic fens provides a source of proxies. suggesting that ombrotrophic bogs are not the only reliable source of data in wetlands for palynological analysis. (C) 2012 University of Washington. Published by Elsevier Inc. All rights reserved.
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A polarimetric X-band radar has been deployed during one month (April 2011) for a field campaign in Fortaleza, Brazil, together with three additional laser disdrometers. The disdrometers are capable of measuring the raindrop size distributions (DSDs), hence making it possible to forward-model theoretical polarimetric X-band radar observables at the point where the instruments are located. This setup allows to thoroughly test the accuracy of the X-band radar measurements as well as the algorithms that are used to correct the radar data for radome and rain attenuation. For the campaign in Fortaleza it was found that radome attenuation dominantly affects the measurements. With an algorithm that is based on the self-consistency of the polarimetric observables, the radome induced reflectivity offset was estimated. Offset corrected measurements were then further corrected for rain attenuation with two different schemes. The performance of the post-processing steps was analyzed by comparing the data with disdrometer-inferred polarimetric variables that were measured at a distance of 20 km from the radar. Radome attenuation reached values up to 14 dB which was found to be consistent with an empirical radome attenuation vs. rain intensity relation that was previously developed for the same radar type. In contrast to previous work, our results suggest that radome attenuation should be estimated individually for every view direction of the radar in order to obtain homogenous reflectivity fields.