4 results on '"Agisoft Metashape"'
Search Results
2. A quick, easy and non‐invasive method to quantify coral growth rates using photogrammetry and 3D model comparisons.
- Author
-
Lange, Ines D., Perry, Chris T., and Cooper, Natalie
- Subjects
CORAL reef ecology ,CORALS ,THREE-dimensional modeling ,CORAL communities ,DIGITAL photogrammetry ,KNOWLEDGE gap theory - Abstract
Coral growth rates vary significantly with environmental conditions and are thus important indicators of coral health and reef carbonate production. Despite the importance of this metric, data are sparse for most coral genera and species globally, including for many key reef‐building species. Traditional methods to obtain growth rates, such as coral coring or staining with Alizarin are destructive and only work for a limited number of species and morphological growth forms.Emerging approaches, using underwater photogrammetry to create digital models of coral colonies, are providing novel and non‐invasive ways to explore colony‐scale growth patterns and to address existing knowledge gaps. We developed an easy‐to‐follow workflow to construct three‐dimensional (3D) models from overlapping photographs and to measure linear, radial and vertical extension rates of branching, massive and encrusting corals after aligning colony models from subsequent years.The method presented here was applied to measure extension rates for 46 colonies of nine coral species in the remote Chagos Archipelago, Indian Ocean. Proposed image acquisition and software settings produced 3D models of consistently high resolution and detail (precision ≤ 0.2 mm) and variability in growth measurements was small despite manual alignment, clipping and ruler placement (SD ≤ 0.9 mm). Measured extension rates for the Chagos Archipelago are similar to published rates in the Indo‐Pacific where comparable data are available, and provide the first published rates for several species. For encrusting corals, the results emphasize the importance of differentiating between radial and vertical growth.Photogrammetry and 3D model comparisons provide a fast, easy, inexpensive and non‐invasive method to quantify coral growth rates for a range of species and morphological growth forms. The simplicity of the presented workflow encourages its repeatability and permits non‐specialists to learn photogrammetry with the goal of obtaining linear coral growth rates. Coral growth rates are essential metrics to quantify functional consequences of ongoing community changes on coral reefs and expanded datasets for key coral taxa will aid predictions of geographic variations in coral reef response to increasing global stressors. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
3. Izrada i analiza točnosti 3D modela Nogometnog stadiona Zagreb
- Author
-
Radulović, Ante
- Subjects
Nogometni stadion Zagreb ,bespilotna letjelica ,3D model ,Agisoft Metashape ,analiza točnosti - Abstract
U diplomskom radu prikazana je geodetska izmjera, izrada te analiza točnosti 3D modela Nogometnog stadiona Zagreb u Zagrebu primjenom bespilotne letjelice. Rad je podijeljen u dva temeljna dijela: teorijski i praktični. U teorijskom dijelu prikazan je razvoj te upotreba sustava bespilotnih letjelica. Sukladno tome, objašnjena je važeća pravna regulativa Republike Hrvatske koja opisuje dva glavna dokumenta: Pravilnik o sustavima bespilotnih zrakoplova te Uredbu o snimanju iz zraka. U praktičnom dijelu objašnjena je geodetska izmjera te izrada 3D modela. Geodetska izmjera obavljena je primjenom bespilotne DJI Phantom 4 PRO V2.0 te su prikupljeni podaci obrađeni u softveru Agisoft Metashape. Objašnjeni su koraci obrade te prikazani konačni rezultati mjerenja: 3D model, digitalni ortofoto i digitalni model visina. Prikazana je te analizirana točnost obrađenih snimaka u Agisoft Metashapeu. Također, provedena je i vanjska ocjena točnost kreiranog 3D modela upotrebom Autodesk AutoCAD-a te je ista analizirana.
- Published
- 2021
4. Study of the energy efficiency of the building of the Polytechnic School of Mining and Energy Engineering of Torrelavega carried out with UAV
- Author
-
Lombilla del Río, Borja, Luis Ruiz, Julio Manuel de, and Universidad de Cantabria
- Subjects
Fotogrametría ,3D model ,Termografía ,Eficiencia energética ,Agisoft Metashape ,Energy efficiency ,Dron ,Thermography ,UAV ,Photogrammetry ,Modelo 3D ,Drone - Abstract
RESUMEN: En la actualidad, la eficiencia energética es un concepto muy extendido e importante ya que es trascendental aprovechar toda la energía generada. De forma convencional, para lograr una eficiencia energética adecuada en los edificios, se lleva a cabo un estudio por medio de un técnico, de los diferentes elementos que inciden en la eficiencia energética del edificio. Después de la realización del estudio, se certifica una valoración energética del edificio. El objetivo principal de este trabajo es la aplicación de otra metodología para el estudio de eficiencia energética de un edificio. Esta metodología consiste en el uso de un dron con cámara dual (obtiene imágenes RGB e imágenes térmicas) que realiza un vuelo fotogramétrico alrededor del edificio para posteriormente generar un modelo 3D térmico. Para la creación de este modelo 3D térmico se emplea el software Agisoft Metashape. Gracias al modelo 3D generado, podemos obtener información térmica de las diferentes fachadas del edificio, así como de su cubierta. Esta información nos permite detectar las zonas del edificio que presentan algún tipo de anomalía. Esta anomalía puede deberse a múltiples factores como: fallos de aislamiento, puentes térmicos, salidas de aire, incidencia solar, etc. La detección de estas anomalías es clave para mejorar la eficiencia energética del edificio, así como para realizar un adecuado mantenimiento del mismo. Hay que tener en cuenta que los resultados obtenidos no son temperaturas sino diferencias térmicas y que estos resultados pueden estar contaminados por la afección de la radiación solar. Se puede concluir que existen zonas con temperaturas muy bajas debido seguramente a entradas y salidas de aire, fallos de aislamiento, pérdidas de frío, etc. y zonas con temperaturas muy elevadas debido a la existencia de puentes térmicos, defectos de aislamiento, zonas que absorben más radiación, etc. Estos puntos donde se detecta una anomalía necesitan de un análisis para un adecuado mantenimiento del edificio. ABSTRACT: Nowadays, energy efficiency is a widespread and important concept, as it is essential to harness all the energy we generate. Conventionally, to achieve adequate energy efficiency in buildings, a study of the different elements that affect it is carried out by a technician. After completing the evaluation, an energy assessment of the building is certified. The main objective of this research is to apply a different methodology to study the energy efficiency of a building. This methodology consists of the use of a dual camera drone (it captures RGB images and thermal images) that performs a photogrammetric flight around the building to subsequently generate a thermal 3D model. Agisoft Metashape software is used to create this 3D thermal model. Thanks to the 3D model generated, we can obtain thermal information from the different facades of the building, as well as its roof. This information allows us to detect the areas of the building that present some type of anomaly. This anomaly could be due to multiple factors such as: insulation failures, thermal bridges, air outlets, solar incidence, etc. It must be taken into account that the results obtained are not temperatures but thermal differences and that these results may be contaminated by the effect of solar radiation. It can be concluded that there are areas with very low temperatures probably due to air inlets and outlets, insulation failures, cold losses, etc.; and areas with very high temperatures due to the existence of thermal bridges, insulation defects, areas that absorb more radiation, etc. These points where an anomaly is detected require further analysis for proper maintenance of the building. Grado en Ingeniería de los Recursos Energéticos
- Published
- 2021
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.