956 resultados para Landsat satellites


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The best irrigation management depends on accurate estimation of reference evapotranspiration (ET0) and then selection of the appropriate crop coefficient for each phenological stage. However, the evaluation of water productivity on a large scale can be done by using actual evapotranspiration (ETa), determined by coupling agrometeorological and remote sensing data. This paper describes methodologies used for estimating ETa for 20 centerpivots using three different approaches: the traditional FAO crop coefficient (K-c) method and two remote sensing algorithms, one called SEBAL and other named TEIXEIRA. The methods were applied to one Landsat 5 Thematic Mapper image acquired in July 2010 over the Northwest portion of the Sao Paulo State, Brazil. The corn, bean and sugar cane crops are grown under center pivot sprinkler irrigation. ET0 was calculated by the Penman-Monteith method with data from one automated weather station close to the study site. The results showed that for the crops at effective full cover, SEBAL and TEIXEIRA's methods agreed well comparing with the traditional method. However, both remote sensing methods overestimated ETa according to the degree of exposed soil, with the TEIXEIRA method presenting closer ETa values with those resulted from the traditional FAO K-c method. This study showed that remote sensing algorithms can be useful tools for monitoring and establishing realistic K-c values to further determine ETa on a large scale. However, several images during the growing seasons must be used to establish the necessary adjustments to the traditional FAO crop coefficient method.

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The present study characterizes the physical environment for its fragility and its capacity to support, through geological and geomorphological properties in the study area, concerning primarily with a sustainable environmental planning for the construction and maintenance of buried linear works. The study area is located on a portion of the Paraiba Valley, which is between the latitudes 22 °30' S and 23°00' S and longitudes 44°30' W and 45° 15' W, between cities of Aparecida (SP) and Queluz (SP). The methodology was based in the visual interpretation of TM/Landsat-7 images, using as a criterion the element textural image and its way of organizing space. To do so, it was set five levels of textural density, enabling thus to the partitioning of the area in areas counterparts (Z.H.s). As a result, it was identified 133 Z.H.s. By using the same criterion textural image the following physical properties were classified: Erosion Resistance, Permeability, Plasticity X Brittle, Tropia and Relief Asymmetry for each zone counterpart, and then grouped themselves as they hold all properties equal in Units Geoenvironmental (U.G.s). As a result it was identified 18 U.G.s. The work presents, as a final result, a thematic map with favorable or restrictable sectores to the design of buried linear works. Based on this map, it can be propose traces to buried linear works, analyzing their suitability to the physical environment and reducing the impacts caused to the environment.

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The climate and weather have direct implications on society, are factors that can to regulate or restrict human occupation in a determined space. In this way, studies of climate and weather are justified to be extremely necessary for urban planning and economic activities, especially agriculture. The precipitation of hail, which enters in the classification of severe storm, causes large, direct and indirect impacts on society, mainly when it occurs in urban areas. This work aims to study the precipitation of hail, explain what is a severe storms and how hail is formed in clouds, making use of a literature review in geography and also in weather sciences. It is also an aim of this work analyze the genesis, evolution and dissipation of a specific case of precipitation of hail occurred in the metropolitan region of São Paulo, especially in Guarulhos, on 21st of September 21 of 2010, through the use of GOES-12’ satellite’s images and the use of São Roque’s weather radar. And in this way, show the potential impact of hail storms in society and contribute to a greater preparedness of the population, urban planners associations and emergency management, such as municipalities, the civil defense and fireman

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The aims of this work are to analyze the direct solar radiation pressure torque (TPRS) in the rotational motion of spin-stabilized artificial satellites, to numerically implement these solutions and to compare the results with real data of the Brazilian Satellite Data Collection – SCD1 and SCD2, supplied by INPE. The mathematical model for this torque is determined for a cylindrical satellite, and the components of this torque are determined in a fixed system in the satellite. An analytical solution for the spin motion equations is proposed, in which TPRSD does not affect the spin velocity of the satellite. Two approaches are adopted in the numerical implementation of the developed theory: the first one considers the proposed theory and the second introduces a variation in the spin velocity based on its real variation. The results obtained indicate that the solar radiation pressure torque has little influence in the right ascension and declination axis of rotation due to the small dimension of the satellite and altitude in which it is found. To better validate the application of the presented theory, the angular deviation of the spin axis and solar aspect angle were also analyzed. The comparison of the results of the approaches conducted with real data show good precision in the theory, which can be applied in the prediction of the rotational motion of the spin-stabilized artificial satellites, when others external torques are considered besides the direct solar radiation pressure torque

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Insetos e outros invertebrados desempenham papel chave nos ecossistemas terrestres por estarem envolvidos com processos de decomposição, ciclagem de nutrientes, polinização, dispersão e predação de sementes, etc. A fragmentação de habitats reduz sua área original, podendo causar extinções locais, alteração na composição e abundância de espécies e levar à perda de processos naturais das comunidades. Além disso, modifica os padrões de distribuição dos organismos, leva a uma redução da fonte de recursos disponíveis, interfere na dinâmica metapopulacional e gera efeitos negativos na abundância e diversidade genética, que pode contribuir para o declínio de muitas espécies. Neste estudo foram identificadas as mudanças de uso e ocupação dos solos ocorridas nos últimos 35 anos no entorno da Reserva de Cerrado de Corumbataí e sua influência sobre sua fauna de abelhas, tendo como referência levantamentos de espécies realizados nos anos de 1982, 1983 e 1984 e em seguida nos anos de 2000 e 2001. As espécies de abelha foram separadas por guildas de polinização para refletir melhor sua diversidade funcional na área de estudo. A vegetação visitada por estas abelhas foi separada de acordo com o bioma ao qual pertence e elaborou-se mapas temáticos de uso e cobertura do solo dos anos de 1975, 1981 e 2010 a partir de geoprocessamento no Spring 5.0 e criação de um Plano de Informação contendo a máscara de 10 Km de raio no entorno do fragmento a partir de imagens de composição colorida das bandas 4, 2, 3 (RGB) do LANDSAT 5, resolução de 30 m e LANDSAT 1 e 2 com resolução de 60 m disponibilizadas pelo Instituto Nacional de Pesquisas Espaciais (INPE). Os polígonos presentes na área de estudo de foram classificados de acordo com seu uso e ocupação em remanescentes florestais, áreas antrópicas e florestas plantadas... (Resumo completo, clicar acesso eletrônico abaixo)

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Infrared spectroscopy (IR spectroscopy) explores the infrared region of the electromagnetic spectrum. Like any other spectroscopic technique, it can be used to identify a compound or the composition of investigate a sample. Spectroscopy (IR) is a very important technique in qualitative chemical analysis, widely used in the chemistry of natural products, organic synthesis and transformations. In this work we study of the theoretical foundations of infrared spectroscopy, the different vibration modes, experimental techniques, and the identification and characterization of solids. Were studied as applications: their use in thermograph and remote sensing satellites

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The Brazilian Environmental Data Collection System (Sistema Brasileiro de Coleta de Dados Ambientais - SBCDA) has been providing reliable information regarding the monitoring of the Brazil environment to INPE (Instituto Nacional de Pesquisas Espaciais) and many Non-governmental organizations (NGO). This system is composed of a large number of Data Collection Plataforms (DCP), in charge of sending local data signals to satellites. Then the satellites automatically redirect each signal to reception centers located at INPE. Nowadays the SBCDA has been operating under the control of three satellites. It is important to mention that two of these satellites have already expired their life span around ten years ago. A strategy to keep the SBCDA operational is to develop a low cost satellite that involves Brazilian Universities and Public Institutions. This graduation work aims to design and simulate a signal conditioning module that enables the collection of a satellite status data, and then sending it to an onboard computer

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After confirming the high specific mechanical properties of composite materials by scientific studies conducted over the last decades, one of the challenges of this new class of materials is the ability to achieve mass production at a more affordable cost, which has become indispensable. The Resin Transfer Molding (RTM) is an excellent method for manufacturing composite materials. Despite being a process widely used by international companies in the production of high performance structural composites, only a short time the national aviation industry has shown interest in implementing this type of processing to more complex structures and greater structural responsibility. In aeronautical projects, the reproducibility and the relative low cost of this process, several studies have been performed in Brazil for learning and perfecting this technique. This process is suitable for producing polymer components both simple as complex geometry, and allows to achieve consistent thickness, with high quality finish and without limiting range. Polymeric composite components for the high mechanical stress applications such as aircraft structures, satellites, etc., require a strict control of volume fractions of the composite constituents, beyond the knowledge of their mechanical and thermal properties. Therefore, in this experimental work degree study on the mechanical, thermal and of porosity composites processed by RTM processed characterization was performed. This characterization was performed targeting a possible aerospace application of this composite material. For the production of composites, process equipment (RTM RTM injector Radius 2100cc) was used. The processed carbono/epoxy composites were characterized via flexure tests mechanically and thermally analysis via DMA, DSC and TGA. To determine the volume fraction of fibers, the composite samples were analyzed via matrix digestion (ASTM D3171) ... (Complete abstract click electronic access below)

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Different forms of human pressure may occur in the pipeline ranges, due to the large extensions and various configurations of land use, which can pass through the pipelines. Due to the dynamics of these pressures, it is necessary to monitor temporal changes of land use and cover the surface. Under this theme, appears as extremely important to use products and techniques of remote sensing, as they allow the identification of objects of the land surface that may compromise the security and monitoring of the pipeline, and allows the extraction of information conditions on land use at different periods of time. Based on the above, this paper aims to examine in a temporal approach, the process of urban expansion in the municipality of Duque de Caxias, located on the outskirts of the metropolitan area of the state of Rio de Janeiro, as well as settlement patterns characteristic of areas that the changes occurred in the period 1987 to 2010. We used the technique of visual analysis to perform the change detection and the technique of image classification, aimed at monitoring human pressure over a stretch of track pipeline Rio de Janeiro - Belo Horizonte, located in the state of Rio de Janeiro. The stages of work involved the characterization of the study area, urban sprawl and the existing settlement patterns, through the analysis of bibliographic data. The processing of Landsat 5 images and the application of the technique of change detection were performed in three scenes for the years 1987, 1998 and 2010, while the classification process was performed on the image RapidEye for the year 2010. Can be noted an increase in urban area of approximately 22.38% and the change of land cover from natural to built. This growth is concentrated outside to the area of direct influence of the duct, occurring in the area of indirect influence of the enterprise. Regarding the settlement patterns of growth areas, it was observed that these are predominantly

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The aim of this work is to analyze the stability of the rotational motion’s artificial satellite using the Routh Hurwitz Algorithm (CRH) and the quaternions to describe the satellite’s attitude. This algorithm allows the investigation of the stability of the motion using the coefficients of the characteristic equation associated with the equation of the rotational motion in the linear form. The equations of the rotational motion are given by the four cinematic equations for the quaternion and the three equations of Euler for the spin velocity’s components. In the Euler equations are included the components of the gravity gradient torque (TGG) and the solar radiation torque (TRS). The TGG is generated by the difference of the Earth gravity force direction and intensity actuating on each satellite mass element and it depends on the mass distribution and the form of the satellite. The TRS is created by changing of the linear momentum, which happens due to the interactions of solar photons with the satellite surface. The equilibrium points are gotten by the equation of rotational motion and the CRH is applied in the linear form of these equations. Simulations are developed for small and medium satellites, but the gotten equilibrium points are not stable by CRH. However, when some of the eigenvalues of the characteristic equation are analyzed, it is found some equilibrium points which can be pointed out as stables for an interval of the time, due to small magnitude of the real part of these eigenvalue

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Construction of linear engineering as, roads, ducts and multiducts as roads, has a strong feature of the diversity of land on which they are deployed. This diversity involves properties geological, geomorphological and structural variety. The purpose of this work is to characterize the physical environment in relation to their ability to support the implementation of civil works linear. To achieve this, the use of orbital remote sensing, in this case, Landsat - TM. Interpretative techniques are applied to images in order to assess the forms of relief and drainage found that they can set properties and have built a favorable meaning or not to implement these works. The results and thematic maps presented in this study allow us to promote the geoenvironmental analysis for the planning phase sustainable linear civil constructions (roads and multiducts)

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On November 26 th, 2005, Rhea, one of Saturn's moons, is found by Cassini spacecraft approximately at 5.105 km from Saturn. Observations in situ reveal that electrons are depleted in the moon's vicinity. However, Rhea is considered massive enough to retain a thin atmosphere. Assumption was that the atmosphere of Rhea was not composed exclusively of gas, its likely contains solid material that can absorb magnetospheric particles. According to Jones et al. (2008), these particles were in a speci c position so that at the moment of observation the electrons could not be detected. In opposition to this idea there is a group, Tiscareno et al. 2010, Cornell University Library, that underwent intensive search for any material that might be orbiting Rhea using Cassini images, however the could not identify any. Second recommendation made by American researchers and other countries, and accepted by the National Board of Research the Cassini Equinox Mission will continue in orbit around Saturn until 2016.The probe will perform several maneuvers with high inclination to delve into the main ring system, and then enter in Saturn's atmosphere and collide with planet. This research is of great importance because until today no rings were found orbiting satellites. The goal of this work is to analyze the orbital evolution of a set of particles around Rhea disturbance of Saturn, J2 e J4 and check results by the numerical simulations and the possibility of a stable ring orbiting Rhea.

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The direct and indirect effects of atmospheric aerossols in the amazonic climate have been focus of many published. This work aims to analyze a possible relation among Burns, atmospheric aerossols and precipitation above South America. It uses the avaluable data from the satellites AQUA/TERRA and TRMM and the images furnished by NOAA and GOES. These analysis can provide some explanations about the effects of emission of aerosols by burns on the composition of atmosphere and cloud formation, mainly in Amazon. We use the Aerosol Optical Depth (AOD) from MODIS/TERRA-AQUA, burns index from CPTEC and rain rate from TRMM. The data we use were obtained from 2000 until 2012. The study is divided in two parts. In the first one, it was performed a quantitative analysis between number of burns and aerosols emission. It was identified a great variability in space and time of the AOD on South America. On the north, northeast and center-west, the AOD is significant during the winter period, with peak on August and September. The southeast is affected by aerosols from center-west due to the dynamical transport. In the second part, it was evaluated the relation between AOD and precipitation in a 13-year period. The statistical analysis shows up a negative correlation of 0.72 between August and October, on Legal Amazon. These result indicate an inverse relation between AOD and rain rate. The other months present not significant correlation. These results are in a good agreement with the literature, in which in-situ methods were applied or combined with satellites data. The increasing of aerosols concentration in the atmosphere are reinforced during drier years. It can affect the increasing process of water drops, decreasing the precipitation. We also verified higher values of AOD (0.25 - 0.3) during years with El Niño, than the climatologically average (~0.15 - 0.2), ... (Complete abstract click electronic access below)

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Pós-graduação em Matemática Universitária - IGCE

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Pós-graduação em Ciências Cartográficas - FCT