Types Of Damage Research Articles

Computer vision-based post-earthquake inspections for building safety assessment

Assessing the safety of earthquake-affected buildings is a critical structural health monitoring task that facilitates the timely response to present dangers and reduces potential threats to life and property. However, post-earthquake time constraints and harsh environmental conditions mean that images and videos taken on-site are frequently affected by poor resolution and blurriness, which may negatively affect the accuracy and usefulness of artificial intelligence image recognition tools. In this study, a HybridGAN model was developed that incorporates ESRGAN for resolution improvement and DeblurGANv2 for blurriness improvement. Additionally, a transfer learning U-Net (TF-Unet) was integrated to detect building components (i.e., columns and structural walls), classify building damage types, and identify building damage levels. Based on recognition results from three case studies and the relevant Taiwan codes, an automated system for building safety evaluation was proposed. The model was trained to directly classify and recognize the level of building component damage. The mean Intersection over Union (mIoU) results for the column and structural wall using the testing dataset were 81.326 % and 57.009 %, respectively. The pre-trained model was used to predict three case studies to test the capability of TF-Unet to handle real-word datasets.

Problems of selection of corrosion-resistant steels and alloys in oil and gas industry for operating conditions

Corrosion-resistant steels and alloys have a number of unique properties. This allows them to be used in various industries. Despite their name, they are to some extent subject to various types of corrosion and corrosion-mechanical damage. This article discusses cases of corrosion damage of products made of corrosion-resistant steels and alloys in the oil and gas industry. The reasons of material failure can be incorrect exploitation of material, low-quality material of products, and incorrect selection of material for operating conditions. For each group of failure causes the examples from open sources and from the practice of the team of authors of this work are considered. The paper substantiates the importance of preliminary laboratory studies of corrosion-resistant materials and their testing with simulation of environmental factors. It is necessary for reasonable choice under specific operating conditions. It is shown that in practice the reasonable choice of corrosion-resistant materials is not always given due attention, so the seemingly economically favorable solutions may turn out to be incorrect. The main focus is made on the practical side of the issue in order to avoid such problems in the future. The relevance of the work is confirmed by the recent acute problem of substitution of foreign steel grades.

Fatigue life analysis of subway e‐clips under multiwavelength rail corrugation excitation

AbstractFatigue‐induced clip fractures are the most common type of damage in railway systems, and they are exacerbated by rail corrugation. This research investigated the development of rail corrugation through long‐term measurements and examined the impact of rail corrugation on the fatigue life of e‐clips using a finite element model. The examination included different corrugation wavelengths, namely, short‐pitch corrugation (SPC), long‐pitch corrugation (LPC), and a new form of corrugation called superposed SPC and LPC. The results showed that increasing corrugation amplitude reduces an e‐clip's fatigue life and alters the region in the clip where fatigue damage occurs. A short corrugation wavelength shortens fatigue life. On railway tracks with superposed SPC and LPC, a significant increase in LPC amplitude sharply reduces a clip's fatigue life, even under minuscule SPC amplitude. Effective measures are proposed to prolong the fatigue life of e‐clips subjected to the effects of rail corrugation.

Application of supervised learning for classification of cracking and non-cracking major damage in TRMs based on AE features

Textile reinforced mortar composites (TRMs) experience various types of damage. In this study, these damage mechanisms (such as cracking and non-cracking) were understood or distinguished with the help of acoustic emissions (AE). Four types of TRMs made of a single mortar matrix and two types of carbon textiles (coated and noncoated) were evaluated under uniaxial tension. Meanwhile, the acoustic emissions were monitored during the tensile test.The study showed that AE features are sensitive to damage evolution but more importantly that TRMs are complex and various modes can coexist. Similarly, the evolution of improved b-value (Ib) also demonstrated sensitivity to the existence of damage. Finally, the supervised learning models (trained on AE data) demonstrated that information on the instant of cracking obtained through digital image correlation (DIC) can be successfully coupled with AE features to separate the cracking and non-cracking damage types with accuracy of above 80 %.

IDENTIFIKASI AWAL BENTUK-BENTUK KERUSAKAN TANAMAN LINGGUA (Pterocarpus indicus, Wild) DI PESEMAIAN

This research aims: as an initial observation, symptoms and signs of damage due to insect attacks or disease on linggua plants in the nursery. The research was carried out at the People's Nursery (KBR) nursery in Liliboi Village, West Leihitu District, Central Maluku Regency, in October 2022. This research included observations of various damages to linggua plants in the nursery at KBR in Liliboi village. Observations were carried out in detail. on leaves, twig shoots and plant stems. Each type of damage is carried out by taking photos and recording the type of damage that occurs. The research results show that the pests and diseases that attack are grasshoppers and leaf spot disease. Grasshoppers can attack young and old plants by damaging the plants' leaves and shoots. Apart from that, grasshoppers have long legs so they can jump very quickly from one plant to another, grasshoppers are poly fat animals. Leaf spot disease has a characteristic, the formation of dead areas on the leaves (necrotic) with varying sizes ranging from small to large, round to angular or irregular which do not die completely unless a number of spots merge together and form large spots, so that the leaf tissue dies.

Damage identification technique by model enrichment for structural elastodynamic problems

Structural Health Monitoring (SHM) techniques are key to monitor the health state of engineering structures, where damage type, location and severity are to be estimated by applying sophisticated techniques to signals measured by sensors. However, very localized damage detection algorithms applied to dynamics problems when dealing with rigid structures at low-frequency range remains still a big challenge. The last due to the low influence of very localized damage on the overall response of the structure (Saint-Venant principle). In this context, in the present work, we propose a methodology for locally correcting the models from collected data for elastodynamics problems at low-frequency range which is able to predict very localized damage. The proposed technique consists in enriching the structural model in a sparse way and solving the identification problem in the frequency domain, where the influence of damage over a large frequency band is exploited to improve the prediction of the damage location. The advantages and potential of the proposed technique are illustrated for the damage detection in a plate problem, demonstrating the advantages of the method in detecting very localized damage. The proposed technique is limited to a methodological description, and further developments should be considered to approach its applicability in an industrial scenario.

El desarrollo decisional de la jurisprudencia del Consejo de Estado colombiano en cuanto a la reparación del daño ambiental consecutivo directo

Between 2004 and 2021, the jurisprudence of the Colombian Council of State on tort liability addressed the study of cases in which the plaintiff, attributing environmental damage to the State, sought full reparation of damages. Given that these damages may deprive certain persons of the use or enjoyment of the values that the ecosystems they inhabit provide them, this research aims to answer the question of what is the ideal way to order the reparation of harm attributable to the State, of the individual facet of the constitutional right to a healthy environment. For this purpose, the methodology of the jurisprudential line proposed by López Medina (2006) is applied to those cases where direct consequential environmental damage is attributable to the State, arguing that the ideal way to compensate for this type of damage is reparation in kind. It is suggested that disregard for the individual facet of the right to a healthy environment in the contentious administrative jurisdiction implies that the reparation of environmental damage is partial; therefore, the study proposes as a solution a sentence in which the Council of State unifies its jurisprudence recognizing the individual facet of this right.

Numerical Investigation of the Effect of Deltoid Radius on Tensile Load in T-joints

In this study, T-shaped joints were designed from composites with different deltoid radius. For this purpose, carbon fiber woven fabrics were preferred as reinforcement elements. Then, tensile analyzes were performed on these composite T-joints. The effect of the deltoid radius on the maximum tensile load and damage behavior of the structure was examined. As a result of the analyses, fiber tensile-compression damage images occurring in the structure for each deltoid radius were obtained along with the load-displacement graph. The Hashin damage criterion was preferred for damage onset. Material Property Degradation (MPDG) method was used for damage progression in progressive damage analysis. By increasing the deltoid radius from 6 mm to 12 mm, the maximum contact load increased by approximately 10%, and by increasing it to 18 mm, the maximum contact load increased by approximately 20.11%. Fiber compression damage, spread over a wide area on the lower surface of the flange where it does not come into contact with the web, was determined to be the dominant damage type, and it was determined that this damage decreased with the increase of the deltoid radius. it was observed that as the deltoid radius increases, the T-jointed composite structure exhibits more rigid material behavior.

Структурные особенности коренных сосняков северной и средней тайги при пирогенных воздействиях

The study of indigenous pine forests of evolutionary formation as endangered virgin forests is the basic for fundamental research into the processes of formation of sustainable forest communities. The aim of the study presented in the article is a comparative assessment of the structures of tree fractions of phytocenoses according to the parameters of the age series of stands and the successional position, dynamic indicators of woody waste, the influence of the pyrogenic factor, and the presence of rot damage to the stands. Age structures, numerical and linear parameters of pyrogenic factors, their impact on the infestation of trees with rot, volumetric indicators of wood waste and characteristics of natural regeneration, the mass of wood xylolysis products during its decomposition by wood-destroying fungi have been studied in pine biogeocenoses with various dynamic characteristics in the taiga zone of European Russia. Pine biogeocenoses under these conditions have structures of different ages, altered by fires of different types. Using the example of an indigenous pine forest in the Pechora-Ilychskiy Nature Reserve (middle taiga), the influence of pyrogenic effects on the formation of various types of rot and damage to trunks is shown. The volumes of woody waste are distributed according to the stages of decomposition in pine forests with different structural and dynamic characteristics; pine undergrowth – according to height gradations. An example is given of calculating the mass of wood components deposited in the stands and released during the decomposition of woody waste by wood-destroying fungi for the biogeocenosis of the Pechora-Ilychskiy Nature Reserve. The majority of indigenous pine forests in the northern territories have been affected by fires of varying intensity and types, sometimes several times during a development cycle. Pyrogenic effects have a significant on changes in the age structures of pine forests, damage to their trunks, the general infestation of forest stands by wood-destroying fungi of the biotrophic complex, the volumes of woody waste, and the formation of natural regeneration structures.

Generalist carabid beetles are more malacophagous than previously recognized and cause diversified types of shell damage

AbstractAlthough most carabids are carnivorous generalists, some species show dietary specializations such as malacophagy, which is characterized by two main strategies of snail predation: entering the shell or breaking it. The shell‐breaking strategy has been well studied in the malacophagous specialists of the tribe Licinini. However, little is known about the ability of other carabids to feed on snails and, in particular, to use the shell‐breaking strategy. Therefore, the main objective of this study was to investigate the ability of various generalist carabid species to feed on snails under laboratory conditions. We recorded 723 instances of predation in 89 of 180 carabid individuals (representing 23 of 33 species); all of them were exclusively shell‐breaking attacks. While carabids mostly favoured individuals <8 mm as prey, they showed no preference for shell shape. Using a subset of 14 carabid species with a high frequency of snail predation, we found significant differences between the predation rates of carabid species depending on their body size using GLMMs. This study revealed that many generalist carabids can indeed feed on snails by breaking the shell, but predation rates were highly inconsistent among individual species. Shell‐breaking patterns of generalists differed markedly from those of malacophagous specialists reported in the literature, as damage parallel to the shell coiling axis occurred more frequently than spiral damage. Our results show that the shell‐breaking predation patterns of carabids are closely related to their degree of dietary specialization on snails and that many generalist carabids frequently accept snails as their prey.

The Influence of Clustered DNA Damage Containing Iz/Oz and OXOdG on the Charge Transfer through the Double Helix: A Theoretical Study.

The genome-the source of life and platform of evolution-is continuously exposed to harmful factors, both extra- and intra-cellular. Their activity causes different types of DNA damage, with approximately 80 different types of lesions having been identified so far. In this paper, the influence of a clustered DNA damage site containing imidazolone (Iz) or oxazolone (Oz) and 7,8-dihydro-8-oxo-2'-deoxyguanosine (OXOdG) on the charge transfer through the double helix as well as their electronic properties were investigated. To this end, the structures of oligo-Iz, d[A1Iz2A3OXOG4A5]*d[T5C4T3C2T1], and oligo-Oz, d[A1Oz2A3OXOG4A5]*d[T5C4T3C2T1], were optimized at the M06-2X/6-D95**//M06-2X/sto-3G level of theory in the aqueous phase using the ONIOM methodology; all the discussed energies were obtained at the M06-2X/6-31++G** level of theory. The non-equilibrated and equilibrated solvent-solute interactions were taken into consideration. The following results were found: (A) In all the discussed cases, OXOdG showed a higher predisposition to radical cation formation, and B) the excess electron migration toward Iz and Oz was preferred. However, in the case of oligo-Oz, the electron transfer from Oz2 to complementary C4 was noted during vertical to adiabatic anion relaxation, while for oligo-Iz, it was settled exclusively on the Iz2 moiety. The above was reflected in the charge transfer rate constant, vertical/adiabatic ionization potential, and electron affinity energy values, as well as the charge and spin distribution. It can be postulated that imidazolone moiety formation within the CDL ds-oligo structure and its conversion to oxazolone can significantly influence the charge migration process, depending on the C2 carbon hybridization sp2 or sp3. The above can confuse the single DNA damage recognition and removal processes, cause an increase in mutagenesis, and harm the effectiveness of anticancer therapy.

Upper Cervical Spine Injuries — A Secondary Publication

Objectives: Based on anatomical knowledge of the upper cervical spine, it is necessary to be familiar with the classification, diagnosis, and treatment strategies currently used clinically for upper cervical spine injuries. Summary of literature review: Upper cervical spine injuries are major injuries with potentially fatal consequences. The occipitocervical junction, which is composed of several structures, protects the brain and cranial nerves. We need to know the mechanism of each type of damage, and in particular, we must understand the anatomy of the occiput, atlas, and axis, as well as the definitions of landmarks of the positional relationships among all structures. Materials and methods: This study reviewed the latest literature on upper cervical spine injuries. Results: In occipital condyle fractures and atlanto-occipital injuries, we should understand how to evaluate instability and the treatment methods according to each classification. In atlas injuries, it should be evaluated whether the transverse atlantal ligament has been damaged. In axis fractures, it is necessary to understand the surgical method according to the shape of the odontoid fracture. Conclusions: Knowledge of soft tissue and bony structural relationships in the upper cervical spine is required for the diagnosis and treatment plan of upper cervical injuries.

Experimental investigation on the fatigue life and damage mechanism of plain weave composites under biaxial tension–torsion combined fatigue loading

In this paper, the fatigue life and damage mechanism of plain weave composites under biaxial tension–torsion combined fatigue loading (TTF) are experimentally investigated. A biaxial TTF loading spectrum is designed to consider different fatigue frequencies and amplitudes, and an automated multi-module loading method with synchronized acquisition of the digital image correlation (DIC) and the testing machine is proposed. A comprehensive analysis of the experimental results, including fatigue lives, strain distribution, temperature variation, stiffness degradation, and typical damage morphologies at different fatigue cycles, has been conducted by utilizing DIC, infrared thermography (IRT) and computed tomography (CT). It is observed that the superimposed torsional fatigue load results in a rapid reduction in fatigue lives of plain weave composites, accompanied by more significant residual strain, energy dissipation, temperature rise and stiffness degradation. Particularly, the superimposed torsional fatigue loads mainly promote matrix cracking and debonding around the fiber/matrix interfaces, which then accelerates the damage initiations and accumulations of fiber yarns, ultimately leading to a rapid reduction in TTF fatigue lives. This study can provide valuable references for the design and safe application of plain weave composites under TTF loading.

Simulation of Radiation-Induced DNA Damage and Protection by Histones Using the Code RITRACKS.

(1) Background: DNA damage is of great importance in the understanding of the effects of ionizing radiation. Various types of DNA damage can result from exposure to ionizing radiation, with clustered types considered the most important for radiobiological effects. (2) Methods: The code RITRACKS (Relativistic Ion Tracks), a program that simulates stochastic radiation track structures, was used to simulate DNA damage by photons and ions spanning a broad range of linear energy transfer (LET) values. To perform these simulations, the transport code was modified to include cross sections for the interactions of ions or electrons with DNA and amino acids for ionizations, dissociative electron attachment, and elastic collisions. The radiochemistry simulations were performed using a step-by-step algorithm that follows the evolution of all particles in time, including reactions between radicals and DNA structures and amino acids. Furthermore, detailed DNA damage events, such as base pair positions, DNA fragment lengths, and fragment yields, were recorded. (3) Results: We report simulation results using photons and the ions 1H+, 4He2+, 12C6+, 16O8+, and 56Fe26+ at various energies, covering LET values from 0.3 to 164 keV/µm, and performed a comparison with other codes and experimental results. The results show evidence of DNA protection from damage at its points of contacts with histone proteins. (4) Conclusions: RITRACKS can provide a framework for studying DNA damage from a variety of ionizing radiation sources with detailed representations of DNA at the atomic scale, DNA-associated proteins, and resulting DNA damage events and statistics, enabling a broader range of future comparisons with experiments such as those based on DNA sequencing.

Improvement of Theaflavins on Glucose and Lipid Metabolism in Diabetes Mellitus.

In diabetes mellitus, disordered glucose and lipid metabolisms precipitate diverse complications, including nonalcoholic fatty liver disease, contributing to a rising global mortality rate. Theaflavins (TFs) can improve disorders of glycolipid metabolism in diabetic patients and reduce various types of damage, including glucotoxicity, lipotoxicity, and other associated secondary adverse effects. TFs exert effects to lower blood glucose and lipids levels, partly by regulating digestive enzyme activities, activation of OATP-MCT pathway and increasing secretion of incretins such as GIP. By the Ca2+-CaMKK ꞵ-AMPK and PI3K-AKT pathway, TFs promote glucose utilization and inhibit endogenous glucose production. Along with the regulation of energy metabolism by AMPK-SIRT1 pathway, TFs enhance fatty acids oxidation and reduce de novo lipogenesis. As such, the administration of TFs holds significant promise for both the prevention and amelioration of diabetes mellitus.

Improved acoustic source localization method for crack identification in structures

Acoustic Emission (AE) monitoring is considered one of the popular non-destructive testing (NDT) methodologies that have been used to predict and identify the location of damage in critical civil infrastructure. In this paper, an improved AE crack localization method is proposed by integrating the empirical mode decomposition (EMD)-based signal decomposition method with a source localization model. Unlike the conventional AE method, the proposed method is free of the use of bulk AE parameters such as counts, rise time, signal strength, and energy. First, EMD is used to minimize the presence of noise in the recorded AE waveforms and extract the key AE components. Then, key AE events are located using the source localization model to localize the crack in concrete structures. The performance of the proposed method is validated experimentally on small and large-scale concrete beams, where the damage is induced using progressive static load testing. In particular, the large-scale beams are designed for flexural and shear mode failure to evaluate the performance of the proposed method under various types of damage. Finally, the results of the proposed method are compared with the traditional method that uses raw AE waveforms and the method that uses bandpass-filtered AE waveforms. The results show higher crack location accuracy of the proposed method than the other methods, which makes it a suitable approach as a crack localization technology.

Predicting the remaining useful life of rails based on improved deep spiking residual neural network

the remaining useful life (RUL) of rails is important to ensure safe and reliable operation of railway transportation lines. However, the severity of deterioration of rails from different types of damage varies. Multichannel vibrational data collected by sensors can be utilized to identify the relevant complex correlations and temporal relationships; however, existing methods struggle to predict rail damage accurately. Thus, this paper proposes a RUL prediction method for rails based on an improved deep spiking residual neural network. First, multichannel data collected by sensors are used directly as input to the predictive network without requiring a separate feature extraction step. Additionally, an encoding module is designed to adaptively convert the temporal sequences of data into spiking signals to reduce the information loss during the encoding process. Second, a spiking residual convolutional neural network (CNN) is incorporated into the proposed method to extract optimal features. The separable, spiking CNN can model the relationships among multichannel data accurately, and an attention mechanism is implemented to recalibrate the spiking feature maps such that the predictive network can distinguish between items of information effectively. Third, the spiking residual connections are altered to mitigate network degradation caused by the incompatibility between the conventional residual connections and the spiking neural network. Finally, the obtained spiking features are input to a fully connected layer to predict the rail RUL. Experimental results demonstrated that the proposed method can predict the rail RUL accurately, and validation results obtained on a rolling bearing dataset demonstrated the high generalizability of the proposed method.

Structural Condition Assessment of Steel Anchorage Using Convolutional Neural Networks and Admittance Response

Structural damage in the steel bridge anchorage, if not diagnosed early, could pose a severe risk of structural collapse. Previous studies have mainly focused on diagnosing prestress loss as a specific type of damage. This study is among the first for the automated identification of multiple types of anchorage damage, including strand damage and bearing plate damage, using deep learning combined with the EMA (electromechanical admittance) technique. The proposed approach employs the 1D CNN (one-dimensional convolutional neural network) algorithm to autonomously learn optimal features from the raw EMA data without complex transformations. The proposed approach is validated using the raw EMA response of a steel bridge anchorage specimen, which contains substantial nonlinearities in damage characteristics. A K-fold cross-validation approach is used to secure a rigorous performance evaluation and generalization across different scenarios. The method demonstrates superior performance compared to established 1D CNN models in assessing multiple damage types in the anchorage specimen, offering a potential alternative paradigm for data-driven damage identification in steel bridge anchorages.

Towards ultrasonic guided wave fine-grained damage detection on hierarchical multi-label classification network

This study advocates the hierarchical multi-label classification (HMC) network for fine-grained damage detection using ultrasonic guided wave. Existing deep learning methods only focus on one aspect of the damage type or the degree of damage progression, and both are important for the long-term safe operation of the structure. To address this limitation, an ultrasonic guided wave HMC network (GHmcNet) and its lightweight version (L-GHmcNet) are developed. The essential designs of the proposed methods are derived from two motivations: (1) achieving robust fine-grained damage classification; (2) designing a lightweight network. The hierarchical labels (defect type-depth-size) are constructed on guided wave data. Inspired by the work of image classification, residual connections are introduced to transfer and fuse features between parent and children categories. The GHmcNet has three output channels and a weighted cross-entropy loss function is imposed on each channel. The weights of the corresponding loss are automatically adjusted during training. To reduce the parameters, we improve the structure of GHmcNet by applying different numbers of convolutional layers and channels at different levels based on the number of classes in each level, proposing the lightweight model L-GHmcNet. Both numerical and experimental studies are carried out, in which the dataset contains signals of different damage types, depths and sizes. The results show the superiority of the proposed methods in terms of accuracy at three levels compared to state-of-the-art methods. Moreover, the high accuracy classification results of L-GHmcNet demonstrate that the proposed lightweight network is a successful attempt.

Numerical simulation of fish damage in a bulb tubular turbine with different guide vane openings

Abstract Tubular turbines have advantages in developing low-head hydropower, however, the development of hydropower shouldn’t forget to maintain a balance with ecology. In this paper, a three-dimensional model of the flow channel of a low-head power plant bulb tubular turbine unit is established using Unigraphics NX, and the hydraulic characteristics and fish damage mechanisms of the turbine under different guide vane openings of 45∼85 mm in rated operating conditions are simulated and analyzed using STAR-CCM+, and it is found that the fish mainly suffers from impact damage and pressure damage in the downstream process with the highest probabilities of 15.73% and 15.72%, respectively. Furthermore, with the increase of the opening of the guide vane, the probability of shear damage to the fish first decreases and then increases, while the probability of pressure, pressure gradient, and impact damage all gradually increase, and the probability of all four types of damage reaches the highest when the opening of the guide vane is 85 mm. Although the unit will have a large output at large opening operating conditions, from the point of view of fish protection, it is better for such turbines not to be operated with large opening of the guide vane for a long time.