Article
Chemistry, Multidisciplinary
Pedro J. Zarco-Perinan, Fco Javier Zarco-Soto, Irene M. Zarco-Soto, Jose L. Martinez-Ramos
Summary: The liberalization of the electricity market has led to the adoption of economic and efficient maintenance techniques. Thermography, a cost-effective and effective maintenance technique, is widely implemented in the electricity sector. This article provides a comprehensive overview of the process and requirements for conducting thermographic inspections in substations, as well as the factors that affect the accuracy of the results.
APPLIED SCIENCES-BASEL
(2022)
Article
Materials Science, Characterization & Testing
Yuzhong Zhang, Kezun Zhang, Wenjing Wang, Shuangbao Shu, Yan Zhang, Xianli Lang, Jingjing Chen
Summary: A simple and effective method is proposed in this paper to enhance the reliability of defect detection in composite materials by eliminating non-uniform surface temperature distribution and using thermographic signal reconstruction coefficients. Experimental results show that this method performs well in detecting defects on CFRP samples.
JOURNAL OF NONDESTRUCTIVE EVALUATION
(2022)
Article
Chemistry, Multidisciplinary
German Alvarez-Tey, Carmen Garcia-Lopez
Summary: Aerial infrared thermography is a powerful and versatile technique for maintenance at photovoltaic plants. It can quickly and reliably detect and locate thermal faults using unmanned aerial vehicles, saving time and costs. Ground-level thermographic inspection provides higher optical resolution but is slower and more costly. Combining both techniques can improve the diagnosis.
APPLIED SCIENCES-BASEL
(2022)
Article
Dentistry, Oral Surgery & Medicine
Niebla Bezerra de Melo, Ligia Natalia Sobreira Duarte, Camila Maia Vieira Pereira, Jussara da Silva Barbosa, Ariane Matos Goncalves da Silva, Renata de Souza Coelho Soares, Patricia Meira Bento
Summary: The majority of the sample had a thin gingival phenotype, which was more prevalent in lower lateral incisors and central incisors. There was a significant and inversely proportional correlation between clinical parameters and gingival temperature, while no significant association could be observed between thermographic parameters and gingival phenotype.
CLINICAL ORAL INVESTIGATIONS
(2023)
Article
Engineering, Multidisciplinary
Gaetan Poelman, Saeid Hedayatrasa, Wim Van Paepegem, Mathias Kersemans
Summary: This paper introduces an improved infrared thermography method for detecting defects in woven fabric composites. The k-space filtering technique is applied to automatically decompose the thermographic image into a structured thermal background image related to the weave pattern, and a residual image representing other features (such as defects). The proposed method demonstrates enhanced performance in defect detection and sizing.
COMPOSITES PART B-ENGINEERING
(2023)
Article
Agriculture, Dairy & Animal Science
Giorgia Fabbri, Matteo Gianesella, Rossella Tessari, Andrea Bassini, Massimo Morgante, Barbara Contiero, Vanessa Faillace, Enrico Fiore
Summary: Young beef bulls are prone to develop growth plate lesions, but current diagnostic methods often rely on the manifestation of severe pain and lameness. This study explored the potential of infrared thermography as a non-invasive tool for rapidly screening beef bulls for the presence of growth plate lesions. The results showed that infrared thermography could accurately diagnose growth plate lesions in beef bulls, allowing for timely treatment and improving animal welfare and production.
Article
Engineering, Mechanical
Zijiao Jia, Marie-Laetitia Pastor, Christian Garnier, Xiaojing Gong
Summary: A new fatigue limit determination method based on thermographic data is proposed in this paper to overcome the limitations of Risitano and Luong's method. The fatigue limit is defined as the maximum stress corresponding to the peak value of the angle change normalized by its amplitude. The evaluation of this method using experimental data of Multidirectional CFRP laminates and literature data for different materials shows that it can effectively determine the fatigue limit of composite laminates regardless of their stacking sequence.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Mechanics
Davide Modesti, Sergio Pirozzoli
Summary: In this study, we performed direct numerical simulations of turbulent flow in a square duct with a focus on heat transfer effects. The results show that the behavior of temperature and streamwise velocity fields are similar, exhibiting logarithmic layers. Furthermore, we found that the traditional hydraulic diameter is a valid reference length for reporting heat transfer data. The study also highlights the limitations of traditional linear closures for turbulent heat flux and suggests that substantial modeling improvements can be obtained by retaining at least the three terms in the vector polynomial integrity basis expansion.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Engineering, Multidisciplinary
Masashi Ishikawa, Masayuki Tsukagoshi, Hideyuki Kasano, Hideo Nishino
Summary: The capability of active thermographic nondestructive inspection of concrete is influenced by the concrete testing condition, especially the concrete composition and surface discoloration caused by efflorescence. While active thermography is barely affected by the variation in concrete composition, it is unsuitable for concrete with great efflorescence due to the reduction in inspection capability.
Article
Thermodynamics
Ranjit Shrestha, Stefano Sfarra, Stefano Ridolfi, Gianfranco Gargiulo, Wontae Kim
Summary: Conservation of artworks is crucial, and non-destructive testing techniques such as active infrared thermography are useful for gentle restoration. X-Ray techniques can also be applied. Numerical simulations help identify defects and provide robust information.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Computer Science, Artificial Intelligence
Emmanuel Resendiz-Ochoa, Irving A. Cruz-Albarran, Marco A. Garduno-Ramon, David A. Rodriguez-Medina, Roque A. Osornio-Rios, Luis A. Morales-Hernandez
Summary: This paper introduces a novel expert system based on infrared thermography and thermal analysis of facial skin and fingertips for classifying and diagnosing stress in undergraduate university students. The system showed a high accuracy rate in the experiment.
EXPERT SYSTEMS WITH APPLICATIONS
(2021)
Article
Thermodynamics
Prashant Singh
Summary: This paper presents an experimental investigation on the primary and secondary peak heat transfer characteristics of an obliquely (45 degrees) impinging jet on a flat and smooth target surface. The effects of jet Reynolds number (Re) and jet-to-target spacings (z/d) have been studied, and the results reveal the dependence of the primary and secondary peak location and heat transfer level on Re and z/d in oblique jet impingement. The comparison with 90 degrees (orthogonal) jet impingement shows that the primary and secondary peaks are sharper and have higher heat transfer levels in the 45 degrees impingement case.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Construction & Building Technology
Van Ha Mac, Jungwon Huh, Nhu Son Doan, Bang Yeon Lee, Achintya Haldar
Summary: This study aims to assess the suitability of detecting deck and soffit delaminations in a concrete bridge deck using thermographic investigation on the shaded side, along with post-processing. The primary contribution is the classification of delaminations as deck or soffit defects based on surface temperature analysis. Weather and time conditions' effects on defect identification are also examined.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Thermodynamics
Ismael Fernandez-Cuevas, Gonzalo Torres, Manuel Sillero-Quintana, Archit Navandar
Summary: Thermography is commonly used to assess training effects and injury risk after training, but results may vary depending on the time of measurement. This study aimed to determine the hourly variation in skin temperature immediately after strength training and examine bilateral differences in temperature. Fourteen physically active university students participated in a longitudinal study, performing a specific exercise protocol. Results showed a significant decrease in skin temperature immediately after exercise, followed by an increase to pre-exercise levels, and further increases in most cases.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Materials Science, Characterization & Testing
Arantza Mendioroz, Agustin Salazar, Paul Lasserre, Beate Oswald-Tranta, Christoph Tuschl
Summary: This article presents a methodology to quantitatively estimate the area and depth of horizontal defects that generate heat, without prior knowledge of the shape of the heat source. The method utilizes the temporal evolution of the temperature and the thermogram obtained at the end of the excitation to extract the necessary data for estimation.
JOURNAL OF NONDESTRUCTIVE EVALUATION
(2023)
Article
Materials Science, Characterization & Testing
Henrique Fernandes, Hai Zhang, Steven Quirin, Jue Hu, Michael Schwarz, Hendrik Jost, Hans-Georg Herrmann
Summary: In this study, infrared thermography is used to detect defects on a 3D hybrid aluminium-CFRP composite structure. A new unsupervised probabilistic low-rank component factorization thermographic denoising model is proposed to improve image performance and defect visualization. Signal profiles and standard deviation analysis are used to assess the results and compare with x-ray CT inspections.
NDT & E INTERNATIONAL
(2022)
Article
Chemistry, Analytical
Pasquale Lafiosca, Ip-Shing Fan, Nicolas P. Avdelidis
Summary: This study discusses the feasibility of automated dent scanning in aircraft using a single-shot triangular stereo Fourier transform algorithm. The modified algorithm improves accuracy and reduces unwrapping errors through the automatic estimation of pass-band filter and the use of a virtual reference plane.
Article
Instruments & Instrumentation
Shakeb Deane, Nicolas P. Avdelidis, Clemente Ibarra-Castanedo, Alex A. Williamson, Stephen Withers, Argyrios Zolotas, Xavier P. Maldague, Mohammad Ahmadi, Shashank Pant, Marc Genest, Hobivola A. Rabearivelo, Antonios Tsourdos
Summary: This work aims to assess the effectiveness of using active infrared thermography (IRT) onboard a UAV platform. It addresses challenges such as interference and identifies optimal distances and time requirements for UAV inspection using IRT. The study demonstrates that UAVs can successfully carry the necessary equipment for locating hard-to-reach defects.
QUANTITATIVE INFRARED THERMOGRAPHY JOURNAL
(2023)
Article
Chemistry, Analytical
Nicolas P. Avdelidis, Antonios Tsourdos, Pasquale Lafiosca, Richard Plaster, Anna Plaster, Mark Droznika
Summary: This paper proposes a two-step process for automating defect recognition and classification in aircraft using an unmanned aerial vehicle (UAV). By using different pretrained CNN models and transfer learning, the proposed method achieves a high accuracy rate of around 82% for defect recognition and 100% for the classification of certain categories.
Article
Energy & Fuels
Chiwu Bu, Tao Liu, Tao Wang, Hai Zhang, Stefano Sfarra
Summary: A convolutional-neural-network-based PV cell fault classification method is proposed in this study, trained on an infrared image data set. An offline data augmentation method is adopted to improve the network's generalization ability. The experiment shows that the proposed model achieves a fault classification accuracy of 97.42%, surpassing the performance of existing models such as AlexNet, VGG 16, and ResNet 18, with faster calculation and prediction speed. This method has high application potential in automatic fault identification and classification of PV cells.
Article
Materials Science, Characterization & Testing
Qi Li, Hai Zhang, Jue Hu, Stefano Sfarra, Miranda Mostacci, Dazhi Yang, Marc Georges, Vladimir P. Vavilov, Xavier P. V. Maldague
Summary: With increasing attention paid to the protection of cultural relics, non-destructive testing (NDT) technologies such as infrared thermography (IRT) and Terahertz time-domain spectroscopy (THz-TDS) are proving to be valuable in detecting defects in ancient buildings and artworks. The present study explores the integration of online/offline background segmentation algorithms, commonly used in video processing, as a feature extraction tool with NDT. Experimental results demonstrate the superior performance of the proposed novel algorithms in detecting defects in a replica painting.
JOURNAL OF NONDESTRUCTIVE EVALUATION
(2023)
Article
Chemistry, Analytical
Bata Hena, Ziang Wei, Clemente Ibarra Castanedo, Xavier Maldague
Summary: In order to meet the growing inspection demand in component manufacturing, non-destructive testing (NDT) explores automated techniques using deep-learning algorithms for defect identification in digital X-ray radiography images. This study investigates the impact of image quality parameters, specifically signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), on the performance of a U-net deep-learning model. Varying combinations of exposure factors were used to acquire input images, and the deep-learning model was trained on datasets categorized by measured SNR and CNR values. Training the model with high CNR values resulted in a higher intersection-over-union (IoU) metric, highlighting the importance of balancing training datasets based on quality parameters for improved performance in NDT digital X-ray radiography applications.
Article
Chemistry, Analytical
Qiang Fang, Clemente Ibarra-Castanedo, Ivan Garrido, Yuxia Duan, Xavier Maldague
Summary: This paper discusses the methods of using deep learning algorithms for defect detection and identification in infrared thermography (IRT) images. The aim is to achieve automatic quality management by integrating deep learning models. Different deep learning methods, as well as traditional methods, were evaluated to compare their effectiveness and performance.
Article
Chemistry, Physical
Jorge Erazo-Aux, Humberto Loaiza-Correa, Andres David Restrepo-Giron, Clemente Ibarra-Castanedo, Xavier Maldague
Summary: This paper presents a simple and reliable method for automated detection of defects in thermal images of composite materials obtained with pulsed thermography. The proposed method is capable of analyzing thermal images with low contrast and nonuniform heating conditions without the need for data preprocessing. The performance of the proposed method for nonuniform heating correction is superior to that of a deep learning algorithm and background thermal compensation by filtering strategy on the same CFRP sample.
Article
Chemistry, Multidisciplinary
Clemente Ibarra-Castanedo, Pierre Servais, Matthieu Klein, Thibault Boulanger, Alain Kinard, Sebastien Hoffait, Xavier P. V. Maldague
Summary: Nondestructive testing (NDT) is crucial in the aerospace industry, and infrared thermography (IRT) techniques such as line scan thermography (LST) and pulsed thermography (PT) are popular due to their speed and versatility. LST is suitable for quickly inspecting large and complex composite parts during production, while PT is used for characterizing composite materials. Results show that although PT generally had higher contrast-to-noise ratio (CNR) values than LST, the majority of defects were clearly detected by LST without advanced signal processing, proving its suitability for inspecting aerospace composite components. Furthermore, PT was used to determine thermal diffusivity and estimate the depth of porosity and damaged areas.
APPLIED SCIENCES-BASEL
(2023)
Review
Chemistry, Multidisciplinary
Muhammet E. Torbali, Argyrios Zolotas, Nicolas P. Avdelidis
Summary: Non-destructive testing (NDT) has gained significant interest in aerospace structures for its non-destructive and economic inspection nature. NDT approaches have been investigated with data fusion to improve inspection performance and obtain more information on structural health condition. This review paper focuses on recent progress in NDT-based image fusion, with particular emphasis on the reliable inspection of aerospace composites and insights from non-composite materials.
APPLIED SCIENCES-BASEL
(2023)
Article
Chemistry, Multidisciplinary
Ziang Wei, Ahmad Osman, Bernd Valeske, Xavier Maldague
Summary: Pulsed thermography is an essential tool in non-destructive evaluation, but processing the data it generates can be challenging. This study presents the PVC-Infrared dataset and evaluates the performance of popular deep learning models on this dataset, addressing a gap in non-destructive evaluation data processing. The results show that appropriate preprocessing techniques can significantly reduce data size while maintaining the performance of deep learning models, highlighting the potential for more efficient and accessible non-destructive evaluation data analysis using deep learning methods.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Civil
Xiaobiao Dai, Junping Hu, Chunlei Luo, Houcine Zerfa, Hai Zhang, Yuxia Duan
Summary: Due to insufficient and uneven lighting, and the scarcity of high-quality datasets, the miss rate of nighttime pedestrian detection is much higher than that of daytime. Vision-based distance detection has low precision and poor robustness, and is mostly performed independently of pedestrian detection. This paper proposes a joint pedestrian detection and distance detection method using a narrowband near-infrared camera and an embedded LiDAR in the system, along with the creation of a large dataset for nighttime driving scenes. The proposed method achieves high accuracy and robustness, with miss rates below 6.5% and absolute error rates of 5.5% for pedestrian detection and distance detection, respectively.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2023)
Article
Archaeology
Zhiyang Zhang, Hai Zhang, Jue Hu, Stefano Sfarra, Miranda Mostacci, Yang Wang, Dazhi Yang, Xavier Maldague, Dongmei Niu, Yuxia Duan
Summary: Early defects in artworks can worsen if not detected in time, and infrared-based non-destructive testing is considered an effective method. However, current methods still rely on human judgment, leading to bias and inconsistency. Therefore, an improved YOLOX algorithm with CBAM mechanism is used to detect defects in artwork using thermal imaging data.
JOURNAL OF CULTURAL HERITAGE
(2023)
Article
Materials Science, Characterization & Testing
Pengfei Zhu, Hai Zhang, Elena Pivarciova, Stefano Sfarra, Xavier Maldague
Summary: A novel normalized time-domain integration method is proposed to detect the delamination of wood materials at different pyrolysis temperatures. The experimental results show the great robustness and detection efficiency of this method. It is also found that meranti is more resistant to pyrolysis and has higher structural stability compared to spruce and oak.
NDT & E INTERNATIONAL
(2023)