Quantifying wood in industrial yards quickly, accurately and at low costs is of great importance for stock management and decision making. In this work, the volume of wood logs stacked in an ...industrial yard was quantified using aerial images with high spatial resolution obtained by remotely piloted aircraft (RPA). The volumetric measurements were tested using the Structure from Motion with Multi-View Stereo (SfM-MVS) photogrammetry technique and compared with values obtained through the conventional manual measurement method. The aerial images were taken at three different flight heights of 60, 80 and 100 m installed at 10 ground control points using a GNSS RTK receptor. The aerial images were processed by digital photogrammetry software to generate digital surface models (DSM), which made it possible to obtain the volumetric measurements of the stacked wood. Thus, aerial images acquired at 60, 80 and 100 m altitude presented variations of 17.50%, 14.93% and 8.31%, respectively. After the statistical tests applied to the results of volumetric estimates, the SfM-MVS photogrammetry did not show significant differences for the conventional measurement method, indicating that the use of aerial images acquired by RPA can be a viable option to estimate the stacked wood volume in an industrial yard.
During the years 2013–2014, the New Southeast Crater (NSEC) at the summit of Mount Etna produced frequent episodes of lava fountaining (paroxysms), and its cone continued to grow at unprecedented ...rates. Many of the episodes were of rather brief duration and violently explosive, producing mostly pyroclastic material and minor volumes of lava. Other episodes, especially those since mid-December 2013, were characterized by violent Strombolian activity without producing sustained lava fountains and significant amounts of tephra, but emitting more voluminous lava flows. One episode of intense Strombolian and effusive activity that was possibly fed from the NSEC conduit occurred from vents located approximately 1km north of the crater, on the east flank of the Northeast Crater, in July–August 2014. The evolution of the NSEC cone between 2012 and 2014 was documented by repeated GPS surveys carried out both from a distance and on the cone itself, by the acquisition of comparison photographs, and by two aerophotogrammetric surveys. From these surveys the highest point of the NSEC results to have grown from 190m (May 2012) to ̴215 m (October 2014) above the pre-cone surface reaching an elevation of 3290m, and its volume more than doubled to ̴ 50.0±6.5×106m3, representing the 40% of the total (bulk) volume of the volcanic products including pyroclastic fallout erupted in 2011–2014, which is 147.2×106m3 (101.3×106m3 dense-rock equivalent). The whole of the 2011–2014 NSEC activity marks an unusually high frequency of rather explosive, tephra-rich eruptive episodes compared to Etna's activity in past decades and centuries, although the average magma production rate in this interval is close to the supposed long-term output rate of the volcano. The latest eruptive episodes show a tendency of the NSEC coalescing with the old Southeast Crater cone, which therefore represents a miniature example of a growing compound volcano at the summit of Etna.
•The New Southeast Crater cone is the fastest-growing volcanic edifice ever documented.•We have documented its evolution with field surveys and aerophotogrammetry.•The 2011–2014 activity included unusually explosive episodes for Etna.•Total volume of 2011–2014 eruptive products is 147.2×106m3 (101.3×106m3 DRE).•Eruptive volumes since 2011 reflect equilibrium between magma supply and eruption.
We are currently experiencing an unprecedented moment in forest restoration, where monitoring activities in recovery areas play a vital role in problem identification and method adaptation. However, ...it is crucial to shift away from expensive traditional methodologies and develop technologies that enable large‐scale monitoring using more accessible and cost‐effective tools. In an effort to provide an evidence‐based perspective, we conducted a systematic review of how remotely piloted aircraft systems equipped with various sensors have been employed for forest monitoring. We consulted three databases and included 53 articles in our review. The results revealed a trend toward research in tropical ecosystems, with forest structure being the most frequently assessed attribute, and canopy height being the most widely measured structural indicator. Red‐green‐blue sensors were commonly used, both individually and in combination with others, and there was a noticeable shift toward the use of light detection and ranging. Data validation primarily relied on forest inventory methods, often involving comparisons of outputs from different sensors and the use of artificial intelligence algorithms. Despite the wide range of studies utilizing sensor‐equipped drones to analyze forest attributes, there is a notable scarcity of research specifically addressing the application of these technologies in forest restoration monitoring. Filling this research gap is essential, as employing techniques that enable large‐scale monitoring, such as aerial photogrammetry and remote sensing, aligns with current trends and contributes to global commitments to environmental restoration and conservation.
Os Petróglifos Cartográficos do Homem Primitivo João Paulo Lopes da Cunha; Edilson de Souza Bias; Ricardo Seixas Brites
Anuário do Instituto de Geociências,
01/2020, Letnik:
42, Številka:
4
Journal Article
Odprti dostop
Registros rupestres deixados por povos pré-coloniais podem estar relacionados com a navegação e orientação espacial. Além das pinturas, mais comuns em sítios arqueológicos, também é possível ...encontrar inscrições de baixo relevo que foram esculpidas em rocha maciça, denominados petróglifos. Por se tratar de inscrições intemperizadas, um desafio dos pesquisadores é desenvolver técnicas que possam mapear tais inscrições sem a necessidade de contato físico rigoroso, possibilitando decifrar as formas geométricas de maneira remota e precisa. O presente estudo testou a viabilidade técnica do uso de produtos georreferenciados, a partir de Aeronaves Remotamente Pilotadas (ARP), objetivando identificar feições em ambiente arqueológico, comparando sua espacialização geométrica com possíveis representações da vida e do cotidiano daqueles antigos moradores pré-coloniais. O local do experimento foi o Sítio Arqueológico do Bisnau, localizado próximo a Brasília, Brasil. Os resultados alcançados foram satisfatórios para geração de modelos digitais georreferenciados, observando a posição, forma e distribuição espacial dos petróglifos em relação ao ambiente local, referências cartográficas e astronômicas.
The tale of two experiences in the geological and cultural heritage area through the use of fixed-wing drones. Innovation and high quality of the data returned from an aero-photogrammetric survey as ...support to the activities of the different professionals. From the survey phase to the post-production all the precautions to obtain images with a very good resolution and solve obstacles for the mapping of areas not easily accessible such as quarries.
ABSTRACT Satellite remote sensing systems are widely used in environmental studies for providing regional scale analyses with high temporal resolution. On the other hand, when local small scale ...spatial studies based on very high resolution data at specific moments are involved, unmanned aerial vehicles have been alternatively adopted. The present case study aimed to carry out the morphometric analysis and quantify the soil loss in two sinkholes located in Oxisol on carbonate rocks of the Paranoá Group, in an agricultural area of Niquelândia, Goiás state, Brazil, using unmanned aerial vehicle, in two periods. From the analyzed satellite images, it was estimated that the emergence period of the sinkholes was between December 2018 and April 2019. Based on the aerial survey carried out, 35.53 m2 of eroded area and 236.89 metric tons of soil loss were observed for the sinkhole 1, as well 299.96 m2 of area and 663.47 metric tons of loss in the first period and 961.66 m2 of area and 4,241.68 metric tons of loss after six months for the sinkhole 2.
RESUMO O sensoriamento remoto por sistemas orbitais é bastante utilizado em estudos ambientais, por permitir análises em escala regional com alta resolução temporal. Já para estudos locais, em pequena escala espacial, com base de dados em altíssima resolução e em momentos específicos, aeronaves pilotadas remotamente têm sido adotadas alternativamente. Este estudo de caso objetivou efetuar a análise morfométrica e quantificação da perda de solo em duas dolinas localizadas em Latossolo sobre rochas carbonáticas do Grupo Paranoá, em área agrícola de Niquelândia (Goiás), utilizando-se aeronave pilotada remotamente, em dois períodos. A partir das imagens de satélites analisadas, estimou-se que o período de surgimento das dolinas foi entre dezembro de 2018 a abril de 2019. Com base no levantamento aéreo realizado, foram observados 35,53 m2 de área erodida e 236,89 t de perda de solo para a dolina 1, bem como 299,96 m2 de área e 663,47 t de perda no primeiro período e 961,66 m2 de área e 4.241,68 t de perda após seis meses para a dolina 2.
Abstract Inspecting historic buildings with non-destructive techniques can contribute to obtaining information about the in-service status of a given building without damaging its parts. Damages map ...prepared by digital photogrammetry and the application of façade Thermography assessment are non-destructive techniques and possible due to technological advances. The present work aimed to apply non-destructive inspection techniques of the façade on the Zoroastro Artiaga Museum, of Art Deco Architecture, using two techniques: generation of damages map by orthoimage created from Aerophotogrammetry and the method of Damage Factor, and application of the thermographic image analysis technique. For the generation of damages map, the relevance of using UAV was observed, since for this technique it is essential to use this equipment to capture images perpendicular to the plane of the façade, when thinking about using the method by Dense Stereo Matching. The damages map generation and the analysis of the Damages Factor allowed the quantification of the incidence of pathological manifestations. The analysis of thermographic images made it possible to understand which factors contributed to the emergence of pathological manifestations, such as the possible presence of excess moisture, favoring, for example, the formation of efflorescence. It is concluded that the application of these techniques can be safely used for inspection and prior diagnosis and that the Thermography was important to identify non-visible damages to the façade, such as moisture extensions, since it was not possible to visually delimit the entire existing area of moisture through damages map generated by Aerophotogrammetry.
In the area of monitoring the spatial conditions and changes at the open pit mines, introduction of aerophotogrammetry with unmanned aerial vehicles significantly improves the effectivity and ...efficiency of the mining system monitoring in real and extended time. Since this is a relatively new technology, the paper presents our first experiences in the application of unmanned aerophotogrammetry, interesting also from the point of view of implementation into GIS systems.
As fotografias aéreas são um dos produtos de sensoriamento remoto mais utilizados nos estudos de erosão, porém a medição direta de feições erosivas lineares sobre as fotos não é adequado, devido aos ...problemas geométricos inerentes a estas. Nesse contexto, este trabalho apresenta um exemplo de aplicação de uma técnica mais precisa para o estudo da erosão a partir de fotos aéreas, a aerofotogrametria digital. Esta foi empregada na análise da evolução temporal (1962 a 2006) de ravinas e voçorocas da bacia do Querosene (São Pedro/SP, sudeste do Brasil). O estudo foi realizado por meio de uma estação fotogramétrica constituída de um notebook, o software DVP e um estereoscópio de espelhos próprio para o uso no computador. Para a correção da geometria das fotos (1962: 1:25.000; 1978: 1.35.000; 1995: 1:25.000; 2006: 1:30.000) foram usados os parâmetros técnicos das câmeras utilizadas nos aerolevantamentos, coordenadas obtidas em cartas planialtimétricas (1:10.000) e um modelo digital de terreno elaborado a partir destas cartas base. Os resultados mostraram o grande potencial da aerofotogrametria digital para visualizar e representar mais precisamente as formas de relevo e as feições erosivas, inclusive de pequenas dimensões, como sulcos e trilhas de pisoteio. Além disso, a medição das dimensões das feições erosivas lineares de 1962 até 2006 permitiu entender a sua evolução temporal e calcular seu ritmo de expansão. O método mostrou-se eficiente não apenas para o estudo da erosão, como também para o mapeamento geomorfológico.
Aiming at the problem of difficult data collection and modeling in high-rise ancient buildings with narrow interiors, a method is proposed in this paper for modeling and supporting digital ...restoration based on unmanned aerial vehicle oblique photogrammetry combined with three-dimensional (3D) laser scanning technology. The ancient watchtower complex in the Tibetan region of China is taken as an example. Firstly, the data is collected using an unmanned aerial vehicle and 3D laser scanner. Secondly, the two types of data are merged to generate a three-dimensional status model. Finally, by analyzing the status model and combining the similar remaining conditions, a virtual restoration scheme is proposed, and a 3D restoration model is established. The results show that virtual restoration based on 3D measurement technology can be used as a new method for the research and protection of towering ancient buildings, asrecorded by adopting targeted technology for digital documentation. It is necessary and effective to adopt a method combining unmanned aerial vehicle oblique photogrammetry and the ground 3D laser scanning technology in harsh environments. The digital model can promote the sustainable utilization of cultural heritage. It is necessary to analyze and make full use of the status model of such ancient buildings based on accurately measured data for the virtual restoration of the damaged ancient buildings. The status model of the ancient buildings can be used for display browsing and disaster recording. The restoration model can be dismantled and used to guide the repair work.
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