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Navegando IESA - Instituto de Estudos Socioambientais por Autor "Alves Júnior, Leomar Rufino"
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Item Análise de produtos cartográficos obtidos com câmera digital não métrica acoplada a um veículo aéreo não tripulado em áreas urbanas e rurais no estado de Goiás(Universidade Federal de Goiás, 2015-03-13) Alves Júnior, Leomar Rufino; Cortes, João Batista Ramos; http://lattes.cnpq.br/0734265787364145; Ferreira, Manuel Eduardo; http://lattes.cnpq.br/4498594723433539; Ferreira , Manuel Eduardo; Oliveira, Ivanilton José de; Jorge, Lúcio André de CastroThis research aimed to verify the precision and accuracy of orthomosaics and Digital Surface Model (DSM) generated automatically by aerial photography taken with an Unmanned Aerial Vehicle (UAV) in urban and rural areas at the cities of Goiânia, Goiás and Edéia, all located in the state of Goiás. The survey also verified for the influence of the scale, depending on the flight height, the influence of the sunlight, and the phenological analysis obtained in agricultural areas with sugarcane and corn (vegetative cycle) crops. Flight plans were drawn up in E-mo-tion software provided by Sensefly - Swiss company manufacturer of UAV Swinglet CAM used in this work. The camera on board UAV was the Canon IXUS 220 HS, with a spatial resolution of 12.1 megapixel, CMOS sensor equipped with type 1 / 2.3" (4000 x 3000 pixel), pixel pitch of 1.54 m, and focal distance equivalent of 35 mm. To check the precision and accuracy of orthomosaics in urban areas, the flights were uniformly distributed in the study area with three-dimensional coordinates pre-marked targets read in the orthomosaic itself, and compared with the coordinates obtained by RTK and static fast positioning methods geodetic survey, using a pair of GNSS signal receiver. Evaluation of Cartographic Accuracy Standards (PEC, defined by the Brazilian decree, no. 89817 of June 20, 1984) was performed by discrepancies between these coordinates. The bias was analyzed by student's t test and the accuracy with the chi-square probability. We have found that in those orthomosaics performed over the urban area in Goiânia city, some buildings were not properly processed in terms of the conical to orthogonal projection; this product was classified as PEC Class A to the 1/250 scale. In Goiás city, the generated orthomosaics without support points were classified as PEC Class A to the 1/2,500 scale, while the orthomosaic generated with eight supporting points was classified as PEC Class A to the 1/1,125 scale. The orthomosaic and MDS generated without ground supporting points presented planialtimetric trends. The mean difference calculated in the orthomosaic with ground supporting was 54 times lower on the E axis, and 111 times lower in N axis, and 10 times lower in the Z axis relative to the average of the discrepancies in orthomosaic without ground control points. The MDS generated with and without supporting showed vertical displacement trend. Thus it was evident the need for supporting points for making orthomosaics and MDS obtained with UAV. In flights performed in crop areas, it was observed that for a better estimate of MPRI vegetation index, the photographs needs to with larger scales (GSD of 5 cm), even with a higher software difficulty in finding homologous points. It did not occur when we used pictures with smaller scales (GSD 20 cm, or larger) for the generation of orthomosaics and MDS.Item Comparação de sistemas imageadores aerotransportados ópticos e LiDAR para quantificação da biomassa em áreas de Cerrado nativo(Universidade Federal de Goiás, 2021-11-14) Alves Júnior, Leomar Rufino; Côrtes, João Batista Ramos; http://lattes.cnpq.br/0734265787364145; Ferreira, Manuel Eduardo; http://lattes.cnpq.br/4498594723433539; Ferreira, Manuel Eduardo; Miranda, Sabrina do Couto de; Oliveira, Ivanilton José de; Rosolen, Vania Silvia; Vieira, Pedro AlvesCurrently, remotely manned aerial platforms (RPAS) embedded with imaging sensors form one of the most desirable and efficient technological sets in the science of remote sensing. Among all possible applications, land use mapping is the flagship, with emphasis on the analysis of native vegetation cover and its relationship with the environment. This research aimed to analyze the woody aerial biomass contained in parcels of native vegetation of the Cerrado biome, located in the Red River basin, state of Goiás, based on advanced instruments (LiDAR and optical sensors) aboard manned aerial vehicles (airplane) and unmanned (RPAS fixedwing, eBee Plus RTK/PPK model). The research also included estimates of native vegetation cover obtained in the field, such as canopy height, number of individuals, percentage of cover and woody aerial biomass, in order to evaluate the efficiency of imaging systems and sensors. The resulting digital surface (MDS) and orthomosaic models were analyzed as a function of accuracy and precision, combining support points and the PPK (Post Processed Kinematic) system. Comparing the orthorosaics generated with support points and without the PPK system, with the orthorosaics generated only with the PPK system, both presented the same planimetric precision, but with improved altimetric precision when the support points were used. For the Cerradão, the model that best estimated the biomass was the one generated with airborne LiDAR data with manned flight, statistically significant with [(F(9.50) = 33.17; p < 0.001; R² = 0.856; SE of the estimate = 0.17 Mg/ha]. For the Dense Cerrado and Cerradão/Dense Forest, the models were statistically significant with [(F(12.27) = 121.264; p < 0.001; R² = 0.982; SE estimate = 0.049 Mg/ha] and [(F(7.42) = 23.360; p < 0.001; R² = 0.796; SE estimate = 0.329 Mg/ha], respectively, both using data obtained with LiDAR Airborne with unmanned flight It is concluded that the use of data obtained with LiDAR and by aerophotogrammetry, from manned and remotely manned aircraft, cannot replace but complement the conventional method of field survey, in the case of native vegetation of Cerrado Denso and Cerradão. As the efficiency in predicting biomass, going from the best to the worst nt, the point cloud obtained with airborne LiDAR with unmanned flight, airborne LiDAR with manned flight, and with aerophotogrammetric survey in unmanned flight. For Cerrado Denso and Cerradão, it can be concluded that all technologies used in this research showed effective results and can therefore be applied according to the availability of equipment and financial resources.