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In recent years, illegal felling of and damage to the incense tree Aquilaria sinensis (Lour.) Spreng. have been reported in Hong Kong. Their native populations are under increasingly severe threat. Therefore, the development of a standard and efficient method to classify and document wounds on vulnerable trees is urgently needed for conservation purposes. In this study, photogrammetry was used to document wounds in A. sinensis through 3D modeling. A total of 752 wound records from 484 individual A. sinensis trees from Hong Kong were included to establish a new wound classification system. Our major findings include a novel standardized procedure for photogrammetric documentation and a wound classification system. The results of this study will facilitate A. sinensis conservation, by enhancing wound documentation and information transfer to law enforcement and education. [ABSTRACT FROM AUTHOR]

Unthinkable just a few years ago, the precise laser‐scanning survey of a kilometer‐long tunnel in one day by one operator has become possible. This article describes how 261 scans were taken with a RIEGL VZ‐400i laser scanner to digitize the Zentrum am Berg (ZaB) research tunnel with millimeter resolution. The data has been automatically registered during the acquisition process within the instrument. After applying multistation adjustment, a block adjustment postprocess step, the high accuracy of the point cloud with respect to a network of 35 retroreflective bireflex targets has been approved. For further applications such as analysis, simulation, or visualization, a homogeneous 3D‐meshed surface model has been created automatically from the point cloud representing an as‐built 3D documentation of the tunnel. [ABSTRACT FROM AUTHOR]

As the coronavirus disease 2019 (COVID‐19) pandemic forced universities to switch to distance online education, there was an urgent need to find some virtual/digital alternatives in order to continue teaching. Opportunities such as watching pre‐recorded autopsy videos or creating and analyzing post‐mortem computed tomography or magnetic resonance imaging with various 3D surface imaging techniques are usually time‐consuming and cost‐intensive. Photogrammetry, which allows the creation of 3D textured surface models from a series of overlapping photographs taken from varying viewpoints, is a less common approach compared with post‐mortem imaging. We created 3D autopsy case models for a special online forensic pathology course in which students could try the models. Then, formal feedback was requested regarding the possible application of this method in education. Most of the students were satisfied with the new method and ranked photogrammetry higher than the other available methods. Our results indicate that photogrammetry has a high potential in undergraduate education, especially in the case of distance education or in those countries where declining autopsy rates have resulted in a decline in the use of the autopsy as an educational tool. Photogrammetry can also be used as a supplementary tool in traditional autopsy‐based education and has potential applications in various fields of medical education. [ABSTRACT FROM AUTHOR]

Three‐dimensional (3D) documenting and rubbing of rock art is aimed to produce descriptive and analytic graphic documentation with metric scale and geospatial information for archaeological analysis. Although the integrated surveying technologies of aerial photogrammetry, close‐range photogrammetry, and laser scanning have been widely used to generate the 3D models of archaeological sites, the implementation of these technologies in complex surroundings with steep terrain, such as riverside cliffs, remains challenging. In this study, we present an unmanned aerial vehicle (UAV)‐based structure‐from‐motion (SfM) photogrammetry approach to obtain the 3D geospatial data of rock paintings. A field data collection approach for high‐resolution multiperspective images using UAV equipped with a high‐resolution camera is implemented together with high accuracy ground control points (GCPs). An appropriate flowchart of multi‐view stereo (MVS) photogrammetry processing is designed including multi‐view dense matching, bundle adjustment (BA) and metric rectification for the orthoimages production of the rock paintings. A digital rubbing approach based on the orthoimages is proposed to obtain the geometry contents, including symbols and characters, of the rock paintings. The Huashan rock paintings, which are located on the vertical faces of the cliffs that line the course of Zuo River, is taken as a case study. Our proposed approach can obtain orthoimages of the Huashan rock paintings with 2 mm resolution. The reality‐based 3D model can reach the absolute accuracy of 5 mm. Clear, exact, and blur‐free metric rubbing images of the Huashan rock paintings are produced, which are useful for the research and preservation of Zhuang culture. [ABSTRACT FROM AUTHOR]