A preliminary backscattered signal model of carbon-fiber-reinforced plastic (CFRP) laminate was established. The backscattered signal model was composed of three sub models, which were concerned with structural signal, scattering signal, and non-acou...
Localized defects are common in gear transmission systems and can sometimes cause serious production problems or even catastrophic accidents. To reveal the failure mechanisms and study the localized defects in gear transmission systems, a 24-degree-o...
Due to bolt looseness or operating ambient temperature, fit clearance can often be found between the outer ring and housing. The vibration characteristics of a cylindrical roller bearing with localized defects are greatly affected by the fit clearanc...
Cross-bonded cables improve transmission efficiency by optimizing the grounding method. However, due to the complexity of their grounding system, they are prone to multiple types of defects, making defect state identification more challenging. Additi...
The timely identification of rail internal defects and the application of corresponding preventive measures would greatly reduce catastrophic failures, such as rail breakage. Ultrasonic rail defect detection is the current mainstream rail defect dete...
Different non-destructive testing techniques have been evaluated for detecting and assessing damage in carbon fiber reinforced plastics: (i) ultrasonic C-scan, (ii) local defect resonance of front/back surface and (iii) lock-in infrared thermography...
20 June 2024
Study Design: Systematic review of the literature. Objective: The goal of this study is to review and summarize current literature on local flap reconstruction of external auditory canal (EAC) defects. Methods: PubMed and Ovid databases were queried...
Automated optical inspection (AOI) for printed circuit boards (PCBs) requires localizing small, sparse defects under illumination drift and minor placement misalignment, while supporting fast, auditable pass/fail decisions. This paper presents a trai...
Due to the long-term service through wheel-rail rolling contact, the train wheelset tread will inevitably suffer from different types of defects, such as wear, cracks, and scratches. The effective detection of wheelset tread defects can provide criti...
Concrete structures frequently manifest diverse defects throughout their manufacturing and usage processes due to factors such as design, construction, environmental conditions and distress mechanisms. In this paper, a multilevel convolutional neural...
Operational amplifiers (op amps) are fundamental blocks that find wide application both as stand-alone devices and as crucial blocks embedded in various Systems on Chips (SoCs). Achieving high defect coverage, as well as performing defect localizatio...
Local defect resonance (LDR) makes use of high frequency vibrations to get a localized resonant activation of a defective region. In this study, the LDR behavior of carbon fiber reinforced polymer (CFRP) coupons with three different types of damages...
Several previous studies have been dedicated to incorporating double defect modes of a phononic crystal (PnC) into piezoelectric energy harvesting (PEH) systems to broaden the bandwidth. However, these prior studies are limited to examining an identi...
Transmission-line defect detection is crucial for grid operation. Existing methods struggle to balance defect localization and fine segmentation. Therefore, this study proposes a novel cascaded two-stage framework that first utilizes YOLOv5s for the...
Local learning algorithms, such as Equilibrium Propagation (EP), have emerged as alternatives to global learning methods like backpropagation for training neural networks. EP offers the potential for more energy-efficient hardware implementation by u...
Surface defect detection is critical in manufacturing magnetic tiles to improve production yield. However, existing detection methods are difficult to use to accurately locate and segment small defects on magnetic tile images, because these defects a...
In this study, both linear and nonlinear vibrational defect imaging is performed for a cross-ply carbon fiber-reinforced polymer (CFRP) plate with artificial delaminations and for a quasi-isotropic CFRP with delaminations at the edge. The measured br...
This study examines the energy-localization performance of a one-dimensional phononic crystal (PnC) with a defect when exposed to burst waves of different cycle numbers under longitudinal waves. Using the finite element method, band structures of the...
The paper presents an approach to efficiently detect local defect resonances (LDRs) in solids with localized defects. The 3D scanning laser Doppler vibrometry (3D SLDV) technique is applied to acquire vibration responses on the surface of a test samp...
At present, the development of power cables shows three notable trends: higher voltage, longer distance and more complex environments. Against this backdrop, the limitations of traditional detection techniques in locating local defects have become in...
Automatic defect detection is an important and challenging issue in the tire industrial quality control. As is well known, the production quality of tire is directly related to the vehicle running safety and passenger security. However, it is difficu...
Railway transportation plays a vital role in modern society, enabling the safe and efficient movement of people and goods over long distances. To ensure the longevity and safety of a railway infrastructure, the regular maintenance of tracks is crucia...
In order to improve the accuracy and detection effect of fabric defect detection, a fabric defect detection method based on local similarity comparison is proposed in this paper. This method first takes each pixel in the image as the central pixel, s...
A response analysis method for nonlinear beams with spatial distribution parameters and non-periodic supports was developed. The proposed method is implemented in four steps: first, the nonlinear partial differential equation of the beams is transfor...
Diffuse wave inspection benefits from multiple scattering and is suitable for the nondestructive testing of complex structures with high sensitivity. This paper aims to localize the defect in a cross-ply carbon fiber reinforced polymer composite with...
As an important component of large engines, inter-shaft bearing is easily damaged due to its poor working conditions. By analyzing the time–frequency distribution rules of fault signals and the evolution law of micro-faults, the bearing failure...
Background: Segmental bone defects (SBDs) pose significant clinical challenges, often requiring complex reconstructive procedures. Degradable bone substitutes loaded with antibiotics have emerged as promising tools for infection control. However, the...
Objectives: Comparison of clinical, radiological, and microbiological outcomes following periodontal regeneration procedures with or without local antibiotic therapy. Methods: Forty patients, each presenting with a single vertical defect, were random...
Corrosion is a major cause of the loss of hermeticity in oil and gas pipelines. Corrosion defects affect the remaining life of in-service pipelines and can lead to failures, ruptures, hydrocarbon leakage, product loss, interruptions, environmental da...
In this work, a defective commercial module with a rounded IV characteristic is analyzed in detail to identify the sources of its malfunction. The analysis of the module includes thermography images taken under diverse conditions, the IV response of...
Manufacturing industries require the efficient and voluminous production of high-quality finished goods. In the context of Industry 4.0, visual anomaly detection poses an optimistic solution for automatically controlled product quality with high prec...
The unit slab track structure in high-speed railways exhibits multiple periodic characteristics, which result in bandgaps of elastic wave propagation within the track structure. Moreover, local defects inevitably occur in the ballastless track struct...
Early fault detection in rotating machinery is crucial for optimizing maintenance and minimizing downtime costs, especially in medium-to-large-scale industrial applications. This study presents a multibody model developed in the Simulink® Simscap...
The presence of defects in substation equipment is a major factor affecting the safety of power transmission. Therefore, timely and accurate detection of these defects is crucial. As intelligent inspection robots advance, using mainstream object dete...
The Local Defect Resonance (LDR) approach is a technique which is used to detect and localize defects in structural components in a non-invasive way. In this contribution, we will assess whether the local resonance frequencies changes by altering a s...
The rolling element bearing is a fundamental component of any rotating machinery. During operation, wear debris and lubricant impurities create dents and bumps on the bearing raceway surfaces. Such localized defects produce transient vibration impuls...
The corrosion, erosion, or worn defects on cylindrical shells often lead to localized wall thinning. The influence of the local wall-thinning defects on the creep buckling behavior of the cylindrical shells serving in high-temperature environments wi...
Using the principal eigenvector (PE) of modal flexibility change, a new vibration-based algorithm for structural defect localization was presented in this paper. From theoretical investigations, it was proven that the PE of modal flexibility variatio...
In powder metallurgy (PM), the compaction step is fundamental to determining the final properties of the sintered components. The deformation and defectiveness introduced in the powder material during uniaxial die compaction can be correlated to the...
Aiming to solve the problem of clearing obstacles in narrow and complex sewers, this paper introduces a visually assisted Sewer Cleaning Robot (SCR) for cleaning sewers with diameters ranging from 280 to 780 mm. The main work is carried out as follow...
The elemental segregation behaviors and interactions between point defects and symmetrical tilt grain boundaries (GBs) in TiVTa concentrated solid–solution alloys (CSAs) have been studied through hybrid Monte Carlo/molecular dynamics (MC/MD) si...
With the development of 3D integrated packaging technology, failure analysis is facing more and more challenges. Defect localization in a 3D package is a key step of failure analysis. The complex structure and materials of 3D package devices demand n...
A new version of an acoustic emission mode which is different from its traditional counterpart is discussed in view of applications for nondestructive testing. It is based on the effect of acoustic waves generation from the defect area in ambient air...
In this paper, the atomic structure and mechanical stability of a new structural graphene modification—a 2D matrix of nanoscale cells in the form of a few-layer graphene substrate and nanoblister of a graphene monolayer—were studied for the first tim...
Due to the increased service life, environmental corrosion, unreasonable construction, and other issues, local defects inevitably exist in civil structures, which affect the structural performance and can lead to structural failure. However, research...
We present STM/STS, ARPES and magnetotransport studies of the surface topography and electronic structure of pristine Bi2Se3 in comparison to Bi1.96Mg0.04Se3 and Bi1.98Fe0.02Se3. The topography images reveal a large number of complex, triangle-shaped...
Defects in coordinated ribosomal RNA (rRNA) transcription in the nucleolus cause cellular and organismal growth deficiencies. Bloom’s syndrome, an autosomal recessive human disorder caused by mutated recQ-like helicase BLM, presents with growth defec...
With the rapid expansion of high-speed rail infrastructure, maintaining the structural integrity of insulators is critical to operational safety. However, conventional defect detection techniques typically rely on extensive labeled datasets, struggle...
Printed circuit board (PCB) defect detection is essential for ensuring manufacturing quality and product reliability in electronics production. PCB designs often exhibit inherent symmetry in circuit layouts and periodic patterns, which defects disrup...
Water gushing is a common engineering geological disaster in the process of foundation pit construction. Its successful judgment directly affects the safety of engineering construction. Taking the case of water gushing at the bottom of the foundation...
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