RESUMO Os remotely piloted aircrafts - RPAs, estão firmados no mercado como poderosa ferramenta de aquisição de imagens aéreas, facilitando os mapeamentos para diversos fins. Assim, objetivou-se avaliar a qualidade dos processos a partir da geração de produtos digitais georreferenciados com diferentes quantidades de pontos de controle (GCPs), utilizando Controle Estatístico de Processos (CEP) e Padrão de Exatidão Cartográfico (MAS) em ortomosaico produzido com imagens de RPA. Foi utilizado um RPA multirrotor para aquisição de imagens aéreas em área de 2 hectares. Posteriormente foi gerado ortomosaico por meio do software PhotoScan, georreferenciado com oito, cinco e três GCPs (Pontos de controles). Os erros de posicionamento foram submetidos ao CEP para avaliar a qualidade dos processos e os ortomosaicos foram qualificados pelo MAS. Os resultados são promissores, tendo em vista os erros de posicionamento menores que 0,1 m nos ortomosaicos gerados, classificados como padrão “A” de Exatidão Cartográfica. Os Controles Estatísticos de Processos demonstraram níveis aceitáveis de erros, indicando grande acurácia para levantamentos desta natureza. As elevadas precisões obtidas nos mapeamentos indicam que imagens aéreas obtidas por meio de RPAs podem ser utilizadas em levantamentos topográficos, contanto que se respeitem os padrões de erros e controle de processos, atestando a qualidade dos resultados.

ABSTRACT Remotely piloted aircraft (RPA) are established in the market as a powerful tool for acquiring aerial images and facilitating mapping for various purposes. The aim of this study was to evaluate the quality of processes originating from the generation of georeferenced digital products employing a differing number of ground control points (GCP), using Statistical Process Control (SPC) and Mapping Accuracy Standards (MAS) in an orthomosaic produced with images from an RPA. A multirotor RPA was used to acquire aerial images over an area of 2 hectares. An orthomosaic was later generated using the PhotoScan software, and georeferenced with eight, five and three GCP (ground control points). Positioning errors were submitted to SPC to evaluate the quality of each process, and the orthomosaics were qualified by MAS. The results are promising, in view of the positioning errors of less than 0.1 m in the generated orthomosaics, which are classified as Mapping Accuracy Standards class ‘A’. Statistical Process Control showed acceptable levels of error, indicating the high accuracy of surveys of this nature. The precision obtained when mapping shows that aerial images obtained by means of RPA can be used in topographic surveys as long as error standards and process control are observed, attesting to the quality of the results.

Surfactants are molecular structures with remarkable physicochemical properties and applications. Most of their characteristics are due to their ability to promote aggregation and interactions with different interfaces. The scarcity of theoretical studies dedicated to evaluating the forces involved in these interactions prompted us to propose other models capable of reproducing the experimental data in better ways. We carried out molecular dynamics (MD) simulations to obtain a model for cetyltrimethylammonium bromide (CTAB), selected from gromos54a7 force field parameters, that better describes most of its behaviors in aqueous solution (micellar structure, counterion dissociation, etc.) and its adsorption pattern on a gold surface. The parameters adopted for one of the models were able to mimic several characteristics suggested by experimental measurements of the CTAB micelles, as well their adsorption pattern on a gold surface. Indeed, this model was able to obtain quasi-spherical micelles, as well as a pattern of adjacent cylindrical micelles with alkyl chain interactions on a gold surface.

ABSTRACT The objective of this study was to evaluate the effect of light availability and salt stress on the growth and quality of hazel sterculia seedlings. The experiment was conducted with two light conditions – full sun (L1), and 50% shading (L2) – and five salinity levels in the irrigation water – 1.0 (S1), 2.2 (S2), 3.2 (S3), 4.2 (S4), and 5.1 (S5) dS m-1. The environment with 50% shading was the most suitable to produce hazel sterculia seedlings, even under high salinity (5.1 dS m-1). Increasing salinity negatively affects the growth and quality of hazel sterculia seedlings. Therefore, controlling sunlight availability and irrigation water saline conditions increases rooting potential and seedling survival in the field.