358 research outputs found

    3D thermal monitoring of jointed rock masses through infrared thermography and photogrammetry

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    The study of strain effects in thermally-forced rock masses has gathered growing interest from engineering geology researchers in the last decade. In this framework, digital photogrammetry and infrared thermography have become two of the most exploited remote surveying techniques in engineering geology applications because they can provide useful information concerning geomechanical and thermal conditions of these complex natural systems where the mechanical role of joints cannot be neglected. In this paper, a methodology is proposed for generating point clouds of rock masses prone to failure, combining the high geometric accuracy of RGB optical images and the thermal information derived by infrared thermography surveys. Multiple 3D thermal point clouds and a high-resolution RGB point cloud were separately generated and co-registered by acquiring thermograms at different times of the day and in different seasons using commercial software for Structure from Motion and point cloud analysis. Temperature attributes of thermal point clouds were merged with the reference high-resolution optical point cloud to obtain a composite 3D model storing accurate geometric information and multitemporal surface temperature distributions. The quality of merged point clouds was evaluated by comparing temperature distributions derived by 2D thermograms and 3D thermal models, with a view to estimating their accuracy in describing surface thermal fields. Moreover, a preliminary attempt was made to test the feasibility of this approach in investigating the thermal behavior of complex natural systems such as jointed rock masses by analyzing the spatial distribution and temporal evolution of surface temperature ranges under different climatic conditions. The obtained results show that despite the low resolution of the IR sensor, the geometric accuracy and the correspondence between 2D and 3D temperature measurements are high enough to consider 3D thermal point clouds suitable to describe surface temperature distributions and adequate for monitoring purposes of jointed rock mass

    Remote sensing image fusion on 3D scenarios: A review of applications for agriculture and forestry

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    Three-dimensional (3D) image mapping of real-world scenarios has a great potential to provide the user with a more accurate scene understanding. This will enable, among others, unsupervised automatic sampling of meaningful material classes from the target area for adaptive semi-supervised deep learning techniques. This path is already being taken by the recent and fast-developing research in computational fields, however, some issues related to computationally expensive processes in the integration of multi-source sensing data remain. Recent studies focused on Earth observation and characterization are enhanced by the proliferation of Unmanned Aerial Vehicles (UAV) and sensors able to capture massive datasets with a high spatial resolution. In this scope, many approaches have been presented for 3D modeling, remote sensing, image processing and mapping, and multi-source data fusion. This survey aims to present a summary of previous work according to the most relevant contributions for the reconstruction and analysis of 3D models of real scenarios using multispectral, thermal and hyperspectral imagery. Surveyed applications are focused on agriculture and forestry since these fields concentrate most applications and are widely studied. Many challenges are currently being overcome by recent methods based on the reconstruction of multi-sensorial 3D scenarios. In parallel, the processing of large image datasets has recently been accelerated by General-Purpose Graphics Processing Unit (GPGPU) approaches that are also summarized in this work. Finally, as a conclusion, some open issues and future research directions are presented.European Commission 1381202-GEU PYC20-RE-005-UJA IEG-2021Junta de Andalucia 1381202-GEU PYC20-RE-005-UJA IEG-2021Instituto de Estudios GiennesesEuropean CommissionSpanish Government UIDB/04033/2020DATI-Digital Agriculture TechnologiesPortuguese Foundation for Science and Technology 1381202-GEU FPU19/0010

    Multi Modality Brain Mapping System (MBMS) Using Artificial Intelligence and Pattern Recognition

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    A Multimodality Brain Mapping System (MBMS), comprising one or more scopes (e.g., microscopes or endoscopes) coupled to one or more processors, wherein the one or more processors obtain training data from one or more first images and/or first data, wherein one or more abnormal regions and one or more normal regions are identified; receive a second image captured by one or more of the scopes at a later time than the one or more first images and/or first data and/or captured using a different imaging technique; and generate, using machine learning trained using the training data, one or more viewable indicators identifying one or abnormalities in the second image, wherein the one or more viewable indicators are generated in real time as the second image is formed. One or more of the scopes display the one or more viewable indicators on the second image

    Efficient generation of occlusion-aware multispectral and thermographic point clouds

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    The reconstruction of 3D point clouds from image datasets is a time-consuming task that has been frequently solved by performing photogrammetric techniques on every data source. This work presents an approach to efficiently build large and dense point clouds from co-acquired images. In our case study, the sensors coacquire visible as well as thermal and multispectral imagery. Hence, RGB point clouds are reconstructed with traditional methods, whereas the rest of the data sources with lower resolution and less identifiable features are projected into the first one, i.e., the most complete and dense. To this end, the mapping process is accelerated using the Graphics Processing Unit (GPU) and multi-threading in the CPU (Central Processing Unit). The accurate colour aggregation in 3D points is guaranteed by taking into account the occlusion of foreground surfaces. Accordingly, our solution is shown to reconstruct much more dense point clouds than notable commercial software (286% on average), e.g., Pix4Dmapper and Agisoft Metashape, in much less time (−70% on average with respect to the best alternative).Spanish Ministry of Science, Innovation and Universities via a doctoral grant to the first author (FPU19/00100)Project TED2021- 132120B-I00 funded by MCIN/AEI/10.13039/501100011033/ and ERDF funds ‘‘A way of doing Europe’

    Automated rapid thermal imaging systems technology

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 266-276).A major source of energy savings occurs on the thermal envelop of buildings, which amounts to approximately 10% of annual energy usage in the United States. To pursue these savings, energy auditors use closed loop energy auditing processes that include infrared thermography inspection as an important tool to assess deficiencies and identify hot thermal gradients. This process is prohibitively expensive and time consuming. I propose fundamentally changing this approach by designing, developing, and deploying an Automated Rapid Thermal Imaging Systems Technology (ARTIST) which is capable of street level drive-by scanning in real-time. I am doing for thermal imaging what Google Earth did for visual imaging. I am mapping the world's temperature, window by window, house by house, street by street, city by city, and country by country. In doing so, I will be able to provide detailed information on where and how we are wasting energy, providing the information needed for sound economic and environmental energy policies and identifying what corrective measures can and should be taken. The fundamental contributions of this thesis relates to the ARTIST. This thesis will focus on the following topics: * Multi-camera synthetic aperture imaging system * 3D Radiometry * Non-radiometric infrared camera calibration techniques * Image enhancement algorithms - Hyper Resolution o Kinetic Super Resolution - Thermal Signature Identification - Low-Light Signal-to-Noise Enhancement using KSRby Long N. Phan.Ph.D

    360-Degree Tri-Modal Scanning: Engineering a Modular Multi-Sensor Platform for Semantic Enrichment of BIM Models

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    Point clouds, image data, and corresponding processing algorithms are intensively investigated to create and enrich Building Information Models (BIM) with as-is information and maintain their value across the building lifecycle. Point clouds can be captured using LiDAR and enriched with color information from images. Complementary to such dual-sensor systems, thermography captures the infrared light spectrum, giving insight into the temperature distribution on an object’s surface and allowing a diagnosis of the as-is energetic health of buildings beyond what humans can see. Although the three sensor modes are commonly used in pair-wise combinations, only a few systems leveraging the power of tri-modal sensor fusion have been proposed. This paper introduces a sensor system comprising LiDAR, RGB, and a radiometric thermal infrared sensor that can capture a 360-degree range through bi-axial rotation. The resulting tri-modal data is fused to a thermo-color point cloud from which temperature values are derived for a standard indoor building setting. Qualitative data analysis shows the potential for unlocking further object semantics in a state-of-the-art Scan-to-BIM pipeline. Furthermore, an outlook is provided on the cross-modal usage of semantic segmentation for automatic, accurate temperature calculations

    Desarrollo de geotecnologías aplicadas a la inspección y monitorización de entornos industriales

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    Tesis por compendio de publicaciones[ES]El desarrollo tecnológico de las últimas dos décadas ha supuesto un cambio radical que está llevando a un nuevo paradigma en el que se entremezclan el mundo físico y el digital. Estos cambios han influido enormemente en la sociedad, modificando las formas de comunicación, acceso a información, ocio, trabajo, etc. Asimismo, la industria ha adoptado estas tecnologías disruptivas, las cuales están contribuyendo a lograr un mayor control y automatización del proceso productivo. En el ámbito industrial, las tareas de mantenimiento son críticas para garantizar el correcto funcionamiento de una planta o instalación, ya que influyen directamente en la productividad y pueden suponer un elevado costo adicional. Las nuevas tecnologías están posibilitando la monitorización continua y a la inspección automatizada, proporcionando herramientas auxiliares a los inspectores que mejoran la detección de fallos y permiten anticipar y optimizar la planificación de las tareas de mantenimiento. Con el objetivo de desarrollar herramientas que aporten mejoras en las tareas de mantenimiento en industria, la presente tesis doctoral se basa en el estudio de como las geotecnologías pueden aportar soluciones óptimas en la monitorización e inspección. Debido a la gran variedad de entornos industriales, las herramientas de apoyo al mantenimiento deben adaptarse a cada caso en concreto. En este aspecto, y con el fin de demostrar la adaptabilidad de la geomática y las geotecnologías, se han estudiado instalaciones industriales de ámbitos muy diversos, como una sala de máquinas (escenario interior), plantas fotovoltaicas (escenario exterior) y soldaduras (interior y exterior). La escala de los escenarios objeto de estudio ha sido muy variada, desde las escalas más pequeñas, para el estudio de las soldaduras y la sala de máquinas, a las escalas más grandes, en los estudios de evolución de la vegetación y presencia de masas de agua en plantas fotovoltaicas. Las geotecnologías demuestran su versatilidad para trabajar a distintas escalas, con soluciones que permiten un gran detalle y precisión, como la fotogrametría de rango cercano y el sistema de escaneado portátil (Portable Mobile Mapping System - PMMS), y otras que pueden abarcar zonas más amplias del territorio, como es el caso de la teledetección o la fotogrametría con drones. Según lo expuesto anteriormente, el enfoque de la tesis ha sido el estudio de elementos o instalaciones industriales a diferentes escalas. En el primer caso se desarrolló una herramienta para el control de calidad externo de soldaduras utilizando fotogrametría de rango cercano y algoritmos para la detección automática de defectos. En el segundo caso se propuso el uso de un PMMS para optimizar la toma de datos en las tareas de inspección en instalaciones fluidomecánicas. En el tercer caso se utilizó la fotogrametría con drones y la combinación de imágenes RGB y térmicas con algoritmos de visión computacional para la detección de patologías en paneles fotovoltaicos. Finalmente, para la monitorización de la vegetación y la detección de masas de agua en el entorno de plantas fotovoltaicas, se empleó la teledetección mediante el cálculo de índices espectrales. [EN]The technological development of the last two decades has brought about a radical change that is leading to a new paradigm in which the physical and digital worlds are intertwined. These changes have had a great impact on society, modifying communication methods, access to information, leisure, work, etc. In addition, the industry has adopted these disruptive technologies, which are contributing to achieving greater control and automation of the production process. In the industrial sector, maintenance tasks are critical to ensuring the proper operation of a plant or facility, as they directly influence productivity and can involve high additional costs. New technologies are making continuous monitoring and automated inspection possible, providing auxiliary tools to inspectors that improve fault detection and allow for the anticipation and optimization of maintenance task planning. With the aim of developing tools that provide improvements in maintenance tasks in industry, this doctoral thesis is based on the study of how geotechnologies can provide optimal solutions in monitoring and inspection. Due to the great variety of industrial environments, maintenance support tools must adapt to each specific case. In this regard, and in order to demonstrate the adaptability of geomatics and geotechnologies, industrial installations from very diverse areas have been studied, such as a machine room (indoor scenario), photovoltaic plants (outdoor scenario), and welding (indoor and outdoor scenarios). The scale of the studied scenarios has been very varied, ranging from smaller scales for the study of welds and machine rooms, to larger scales in the studies of vegetation evolution and the presence of bodies of water in photovoltaic plants. Geotechnologies demonstrate their versatility to work at different scales, with solutions that allow for great detail and precision, such as close-range photogrammetry and the Portable Mobile Mapping System (PMMS), as well as others that can cover larger areas of the territory, such as remote sensing or photogrammetry with drones. The focus of the thesis has been the study of industrial elements or installations at different scales. In the first case, a tool was developed for external quality control of welding, using close-range photogrammetry and algorithms for automatic defect detection. In the second case, the use of a PMMS is proposed to optimize data collection in fluid-mechanical installation inspection tasks. In the third case, drone photogrammetry and the combination of RGB and thermal images with computer vision algorithms were used for the detection of pathologies in photovoltaic panels. Finally, for the monitoring of vegetation and the detection of water masses in the environment of photovoltaic plants, remote sensing was employed through the calculation of spectral indices
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