Types Of Defects Research Articles

Analisis Pengendalian Kualitas untuk Mengurangi Cacat Produk 3D VR (Virtual Reality) Garment dengan Menggunakan Metode Six Sigma

Pan Brothers Tbk is one of the garment companies that adopted garment production in the form of 3D VR (Virtual Reality) as a garment prototype in Indonesia. In the process of making 3D VR products, many defective products must be revised. The study aims to implement the Six Sigma method and suggest improvements to reduce defects in 3D VR garment products using the Six Sigma method with the stages of defining, measuring, analyzing, improving, and controlling. In the define stage, the identification of the production process using the SIPOC diagram and identifying the type of defect. In the measure stage, the DPMO and sigma value calculations are carried out. The most defects are fitting not balanced and properly with a DPMO value of 269619.2 and a sigma value of 2.11. In the analysis stage with a fishbone diagram shows the factors that cause defects, namely man, machine, material, method, and environment. In the improvement stage, suggestions for improvements are given to reduce defects in 3D VR garment products. In the control stage, quality control is carried out by conducting internal training, upskilling, creating inspection report forms, adding teams to the QC division, and adding SOPs for the 3D VR producing process.

Determining the density and spatial descriptors of atomic scale defects of 2H–WSe2 with ensemble deep learning

We have demonstrated atomic-scale defect characterization in scanning tunneling microscopy images of single crystal tungsten diselenide using an ensemble of U-Net-like convolutional neural networks. Coordinates, counts, densities, and spatial extents were determined from almost 16 000 defect detections, leading to the rapid identification of defect types and their densities. Our results show that analysis aided by machine learning can be used to rapidly determine the quality of transition metal dichalcogenides and provide much needed quantitative input, which may improve the synthesis process.

Meat Color, Marbling, and the Evaluation of Defects in Beef and Pork at the Point of Purchase

Intentions to purchase meat and repeat purchasing patterns will depend on the consumer’s perception of intrinsic and extrinsic quality cues. In order to discover consumers’ insights into the quality of pork and beef, the main objective of this study was to investigate meat color, marbling, and types of fresh meat defects. A total of 50 samples of meat were analyzed for three quality characteristics on different levels. This study applied a statistical calculation of a loss function invented by Taguchi. The results showed the values of variations in meat color and marbling that present the limits of consumers’ tolerance. Based on the obtained results, it was determined that the tolerable level of color variations of beef is 3.61, while for pork, this limit is 2.00. The most preferred marbling percentages were 21% and 5.74% for beef and pork, respectively. On the other hand, the negative effect of defects was the strongest for “dark cutting” for beef and “blood spotting” for pork loins.

Data acquisition system for OLED defect detection and augmentation of system data through diffusion model

This paper presents a system and model for data acquisition and augmentation in OLED panel defect detection to improve detection efficiency. It addresses the challenges of data scarcity, data acquisition difficulties, and classification of different defect types. The proposed system acquires a hypothetical base dataset and employs an image generation model for data augmentation. While image generation models have been instrumental in overcoming data scarcity, time and cost constraints in various fields, they still pose limitations in generating images with regular patterns and detecting defects within such data. Even when datasets are available, the precise definition and classification of different defect types becomes imperative. In this paper, we investigate the feasibility of using an image generation model to generate pattern images for OLED panel defect detection and apply it for data augmentation. In addition, we introduce an OLED panel defect data acquisition system, improve the limitations of data augmentation, and address the challenges of defect detection data augmentation using image generation models.

Solid-state friction rolling repair technology for various forms of defects through multi-layer multi-pass deposition

The current Friction Stir Welding (FSW) based solid-state defect repairing method is an ideal repair technology for high-strength aluminum alloy. However, due to the limitation of pin length and the existence of shoulder, the stirring pin cannot penetrate deep into the root of defects and is difficult to extend in the width direction, which poses great challenges for components with large defects, such as one-dimensional, two-dimensional and volume defects. To overcome these limitations, this study successfully achieved effective repair of various forms of defects using the solid-state Friction Rolling Repair (FRR) technology through multi-layer multi-bead deposition. The microstructure and mechanical properties of the repaired ZL114A cast aluminum alloy joints were investigated. The results demonstrate well-bonded repaired boundaries, significant grain refinement at the junction between the repaired area and boundary, and ultimate tensile strength exceeding 80 % of base material strength. The average grain size of the repaired area can reach a minimum of 2.82 μm. The grain refinement degree of the side joint of the surface defect repair sample is higher than that of the bottom joint, and the corner joint of the bottom surface shows the highest proportion of recrystallized grains. Fracture locations were consistently within the interior of the repair zone in tensile specimens, indicating superior properties at side joints compared to those within the interior. The research proves that FRR has the ability to repair a variety of typical defects, including one-dimensional, two-dimensional and volume defects, in the process of processing and service, which lays a foundation for the industrial application of FRR.

Abstract We088: Spatiotemporal analysis of cardiac progenitor cells reveals migratory characteristics during epithelial-mesenchymal transition

Introduction: Congenital heart defects (CHD) are one of the most common types of birth defects, with a rising prevalence in mild types. The most frequent CHDs include anomalies in the cardiac outflow tract (OFT), which mainly derives from multipotent cardiac progenitor cells termed second heart field (SHF). Hence, dysregulation of highly synchronized, chronological sequence of proliferation and differentiation of SHF cells could lead to severe CHDs. As the SHF contributes entirely to the OFT, mutations in the SHF-related genes lead to major arterial pole defects which account for one third of CHDs in newborn children. Investigating how these genes regulate cell-cell behavior and communication is of vital importance. Hypothesis and Methods: In this study, we employed a multidimensional approach to assess the hypothesis that the dynamic behavior of SHFs is regulated by key genes implicated in CHD pathogenesis. Leveraging single-cell RNA sequencing (RNA-seq) data obtained from experimentally dissected mouse OFT, we delineated distinct epithelial-to-mesenchymal transition states within SHF cell populations. Additionally, we developed a quantitative metric to assess SHF cell’s migratory level and integrated it with spatial transcriptomic analyses to map the developmental trajectory of SHFs. Results and Conclusion: Through spatiotemporal analysis, we identified a panel of key genes associated with SHF migration, shedding light on the molecular mechanisms underlying OFT development during early embryonic stages. Furthermore, we leveraged the data from The Pediatric Cardiac Genomics Consortium (PCGC) study (phs001194.v3.p2) which comprises a large cohort of CHD patients (13716 participants) and a proportion of 21.68% identified with OFT obstruction in its sub-study. In conclusion, using these datasets and quantitative metric being developed, we validated the SHF-derived genes in the PCGC participants and revealed specific expression patterns of these genes associated with OFT-specific CHDs. These results would benefit the understanding of the genetic regulation of SHF proliferation and differentiation, which is crucial for early detection and precise surgical intervention in CHD patients.

Abstract We087: The mitochondrial citrate carrier SLC25A1 is a regulator of metabolic reprogramming and morphogenesis in the developing heart

Background: Congenital heart defects (CHDs) are the most common type of birth defect, yet the etiology of most CHDs are unknown. A major genetic risk factor for CHD is 22q11.2 deletion syndrome (22q11.2DS), a multisystem chromosomal microdeletion disorder where ~75% of patients present with CHD. SLC25A1 is a gene found within the 22q11.2DS microdeletion region that encodes for the mitochondrial citrate carrier, an inner membrane transporter that regulates intracellular citrate compartmentalization. Through this role, SLC25A1 is thought to contribute to cytosolic acetyl-CoA availability, and processes like protein acetylation and the epigenetic regulation of gene expression. We have previously found that SLC25A1 is a central gene contributing to the neurodevelopmental presentation of 22q11.2DS and importantly, neuronal mitochondrial function. Because the heart, like the brain, is highly reliant on energy derived from mitochondria, and the developing heart must undergo metabolic maturation whereby metabolism is reprogrammed from primary reliance on glycolysis towards mitochondrial oxidative metabolism, we hypothesized that SLC25A1 plays a key role in the metabolic maturation that is required for proper cardiac development. Objective: Here, we studied the role of Slc25a1 in the developing heart to examine the link between mitochondria and cardiac morphogenesis. Methods and Results: By studying mice with the systemic knockout of SLC25A1, we discovered that Slc25a1 null embryos displayed impaired growth, cardiac malformations, mitochondrial ultrastructural defects and impaired mitochondrial oxygen consumption. Transcriptomics analyses of metabolism-related genes revealed that Slc25a1 deletion causes widespread alterations in metabolic gene expression. Further, metabolic modelling predicted that loss of SLC25A1 downregulates oxidative phosphorylation, while increasing reliance on glucose. Finally, we found that loss of SLC25A1 decreases cardiac H3K9 acetylation levels at promoter regions of dysregulated metabolic genes. Mechanistically, SLC25A1 may regulating mitochondrial function and metabolism through epigenetic control of gene expression to promote metabolic remodeling in the developing heart. Conclusions: Our work suggests that SLC25A1 as an an important mitochondrial regulator of gene expression in the developing heart. Importantly, it positions SLC25A1 as a novel mitochondrial regulator of ventricular morphogenesis as well as cardiac metabolic maturation.

Analisis Produk Cacat pada Block Beton Menggunakan Metode Seven Tools dan Failure Mode Effect Analysis di Perusahan Precast XYZ

XYZ Company is a company in the manufacturing sector of precast concrete production, ready-to-use concrete products to meet the needs of the construction industry. The problem in this company is that there are still many defects that occur in the concrete produced. The purpose of this study is to find out what defects occur in concrete blocks, analyze the causes of their occurrence and make repair suggestions. This study uses the seven basic tools method to analyze the types of defects and the causes of defects in concrete blocks, and the FMEA method to make repair recommendations with the cause of defects from the highest RPN value. Based on the results of data processing, there are several defects that occur in concrete blocks, namely: porous, small cracks, non-angled products, non-uniform colors, bubbles, dimensions, gripis, and hairline cracks. From the Fishbone results, there are 18 indicators of the causes of the three defects, from the 18 causes of defects, the RPN value is then determined with the highest RPN value of 168, namely dirty, leaking, and less tight mold indicators..

Effect of Ni addition on the crystallization behaviors of Cr-Co alloy

Optimizing the crystallization kinetics of Cr-Co alloys through doping is of practical significance to their industrial applications. By employing molecular dynamics (MD) simulations, this study investigates the effect of Ni concentration on the solidification process of Cr30Co70-xNix (x=0, 10, 20, 30, 40) alloys, focusing on crystallization behavior during quenching and microstructural characterization. The evolution of potential energy indicates that higher Ni concentrations promote crystallization, resulting in a lower liquid-solid transition temperature and enhanced relaxation. However, Ni doping does not alter the preference for chemical ordering, with Cr-Co bonding predominant across all the compositions. Microstructural analysis reveals a shift towards fcc-dominant ternary alloys with increased Ni content. Furthermore, Ni addition impacts defect distribution, notably reducing "other" types of defects in the Cr-Co binary alloy. These findings provide a quantitative reference for adjusting the crystallization behavior of Cr-Co alloys through doping, with implications for their design, manufacturing, and utilization.

Trans-Abdominal Pre-Peritoneal (TAPP) Approach for Anatomical Repair of Direct Inguinal Hernia in Children, Could it Be the New Standardized Approach?

BackgroundThe incidence of direct inguinal hernia in the pediatric population is relatively low and is usually discovered intraoperatively, rendering it unfamiliar to most pediatric surgeons. The traditional approach involves directly addressing the peritoneal defect, which includes dissecting the sac and repairing the peritoneum, reinforced with the umbilical ligament. In this paper, we present our experience with a novel approach to anatomical repair utilizing a non-mesh transabdominal preperitoneal (TAPP) approach. MethodsThis a retrospective case series of direct inguinal hernia that were operated laparoscopically using the novel approach of repair from January 2018 to January 2024. Data were analyzed for demographics, presentation, type of defect, operative time, complications, and recurrence. The new approach utilizes the pre-peritoneal approach to delineate the exact facial defect then, primary anatomical repair is established using 2/0 non-absorbable braided sutures. Finally, closure of the peritoneum was performed using running 4/0 absorbable sutures.This is a retrospective case series of direct inguinal hernias that were operated on laparoscopically using the novel repair approach from January 2018 to January 2024. Data were analyzed for demographics, presentation, type of defect, operative time, complications, and recurrence. The new approach employs the pre-peritoneal approach to accurately delineate the fascial defect, followed by primary anatomical repair using 2/0 non-absorbable braided sutures. Finally, the peritoneum is closed using running 4/0 absorbable sutures. ResultsData from nine cases were included. Six cases were on right side, and three cases were on left side. Patients were predominantly boys (8 boys and 1 girl). The mean age at operation was 25.1 months (range:11 month to 5 years). Four patients had previous indirect inguinal hernia repair on the same side. The mean operative time was 34 ± 9 min. No intraoperative complications occurred. The median follow up period was 24 months with no recurrence was detected in any of the cases. ConclusionThe non-mesh TAPP approach offers excellent exposure of the fascial structures, facilitating accurate identification and repair of the defect. Despite being technically demanding, it allows for the establishment of a robust anatomical repair. No recurrences occurred in the study group; however, a longer follow up and a larger sample are needed to provide more reliable evaluation. Level of EvidenceIII.

Comparative analysis of femoral bone loss: uncemented vs. cemented aseptic stem loosening in first-time revision surgery—a retrospective evaluation of 215 patients

IntroductionThe integrity of the femoral bone is crucial when considering reconstructive options for the first-time revision of a total hip arthroplasty (THA). Aseptic loosening of primary stems, whether cemented or uncemented, significantly affects the volume and quality of resultant femoral bone loss. This study evaluates the impact of the initial fixation method on femoral bone defect patterns by comparing the extent of bone loss.Materials and methodsA retrospective cohort of 215 patients with either cemented or uncemented stems, indicated for aseptic stem loosening, and undergoing first-time stem revision from 2010 to 2022 at our institution was analyzed. Femoral bone loss extent at first-time revision was preoperatively gauged using radiographs and categorized by the Paprosky classification. Survival probabilities pre-first-time revision for both stem types were calculated using Kaplan–Meier methods. Hazard ratios were applied to compare the risk of initial revision for uncemented versus cemented stems within the first and subsequent 2nd to 10th years post-primary implantation.ResultsCemented stems were associated with a higher occurrence of significant bone defects of type 3a (23.53% vs. 14.02%, p = .108), 3b (39.22% vs. 1.22%, p < .001), and 4 (3.92% vs. 0.00%) compared to uncemented stems. Conversely, smaller defects of type 1 and 2 were more prevalent in uncemented stem loosening (84.76% vs. 33.33%, p < .001). Notably, cemented stems exhibited a significantly prolonged revision-free period over the complete decade following primary insertion (p < .001). The unadjusted risk of first-time revision due to stem loosening showed a tendency to an increase in uncemented stems within the initial postoperative year (HR 5.55, 95% CI 0.74; 41.67, p = .096), and an adjusted risk of 2.1 (95% CI 0.26; 16.53, p = .488). However, these differences did not reach statistical significance. In the subsequent 2nd-10th years, the risk was lower compared to cemented stems (HR 2.35, 95% CI 1.39; 3.99, p = .002).ConclusionsUncemented primary stems necessitating first-time revision due to aseptic loosening demonstrated notably smaller femoral bone defects in comparison to primary cemented stems.

Influence of printing parameters on part density in L-BPF of Ti-6Al-4V and correlation with static mechanical properties measured using indentation testing

Abstract A complete workflow of parameter development and process qualification of a part manufactured using laser powder bed fusion (L-PBF) AM technique requires data of porosity, pore morphology, distortion and static mechanical properties. Using a combination of two non-destructive techniques: Computed tomography and indentation testing, the influence of printing parameters on defect types and part density in L-PBF of Ti-6Al-4V is described. In addition, the results using the combined method are compared to conventional testing methods.

Efficient photocatalytic degradation of diclofenac drug using the Zn1-x-yPrxAlyO photocatalyst under UV light irradiation.

Herein, we report the efficient photocatalytic degradation of the diclofenac drug using the Zn1-x-yPrxAlyO photocatalyst [x, y] = (0.00, 0.00), (0.03, 0.01), (0.03,0.03) under UV light irradiation. The analysis of the structure reveals that the Pr3+ and Al3+ cations insertion into the ZnO lattice leads to a decrease in the lattice constant (a and c), Zn-O bond length, strain lattice, and crystallite size. These alterations are linked to the high degree of atomic disorder triggered by the dopants, which produce stress and strain in the ZnO structure. The Raman measurements confirmed the structural phase and showed changes in the position and intensity of the E2High mode, associated with oxygen vibrations and material crystallinity. The presence of the dopants reduces the concentration of VZn and VO++ type defects while increasing the levels of VO, VO+, and Oi defects, as observed from the fitting of the Photoluminescence spectra. Furthermore, it was noted that de Pr3+ and Al3+ cations insertion into ZnO increases the optical band gap, which is associated with the Moss-Burstein effect. The micrograph images show that dopants transform the morphology from quasi-spherical particles to irregular cluster structures. The textural analysis indicated that an increase in the concentration of Al3+ in the ZnO lattice led to a higher surface area, likely enhancing photocatalytic activity. The sample containing 3% Pr3+ and 3% Al3+ showed the highest photocatalytic activity and degraded up to 71.42% of diclofenac. In addition, experiments with scavengers revealed that hydroxyl radicals are the main species involved in the drug's photodegradation mechanism. Finally, the Zn1-x-yPrxAlyO compound is highly recyclable and stable.

Photon emission microscope analysis on surface defects of GaAs thin-film solar cells grown by molecular beam epitaxy

Surface defects seriously affect the electronic properties of the optoelectronic devices. In this paper, the surface defect analysis of GaAs thin-film solar cells grown by molecular beam epitaxy is carried out by a photon emission microscope. Two types of oval defects at the locations of the luminous spots are observed. The morphology and chemical composition analysis indicates that GaAs dust contamination on the wafer surface and excessive As clusters are the origins of oval defects. The electrical property analysis shows that oval defects in the epitaxial layer should be one of the important reasons for the nonideal leakage current of the GaAs thin-film solar cell.

Phonon modal analysis of thermal transport in ThO2 with point defects using equilibrium molecular dynamics

Defects can significantly degrade the thermal conductivity of ThO2, an advanced nuclear fuel material as well as a surrogate for other fluorite-structured materials. We investigate how point defects in ThO2 impact phonon mode-resolved thermal transport. By incorporating phonon modes from lattice dynamics, we decompose the trajectory and heat flux to phonon normal mode space and extract key phonon properties, including phonon relaxation times and their contributions to thermal conductivity. We implement two methods. The first method is based on the Green Kubo formalism to resolve the contribution of each phonon mode to thermal conductivity. The second resolves the lifetime of individual phonon modes and the thermal conductivity is calculated using the Boltzmann transport equation within relaxation time approximation. Notably, a lower contribution of acoustic modes is revealed compared to perturbative approaches considering only three-phonon scattering processes. The effects of four types of point defects are evaluated. The strongest impact on a reduction in thermal conductivity is from Th interstitials, followed by Th vacancies. O interstitials/vacancies have a similar impact, albeit smaller than defects on the thorium sublattice. These observations are consistent with previous studies.

Failure analysis of unidirectional CFRP composites with the coupled effects of initial fibre waviness and voids under longitudinal compression

This research delves into the failure mechanisms exhibited by unidirectional Carbon Fiber Reinforced Polymer (CFRP) composites under longitudinal compression, while considering the interplay of three types of manufacturing-induced defects: initial waviness of fibres, void volume fraction, and void size. The study employs 3D high-fidelity intact representative volume element (RVE) models, incorporating the initial waviness of fibres and voids based on Micro-CT imaging. A novel algorithm is proposed to generate more accurate 3D void shapes, departing from conventional circular or triangular approximations. The results highlight the substantial influence of the initial waviness angle on the reduction of predicted compressive stiffness and strength. The volume and size of voids play a significant role in determining damage initiation within the composites. The failure mechanisms of the composite under the coupled effects of initial waviness of fibres and voids are discussed, exhibiting reasonable agreement with experimental observations.

Effect of Etching Methods on Dielectric Losses in Transmons

Superconducting qubits are considered as a promising platform for implementing a fault tolerant quantum computing. However, surface defects of superconductors and the substrate leading to qubit state decoherence and fluctuations in qubit parameters constitute a significant problem. The amount and type of defects depend both on the chip materials and fabrication procedure. In this work, transmons produced by two different methods of aluminum etching: wet etching in a solution of weak acids and dry etching using a chlorine-based plasma are experimentally studied. The relaxation and coherence times for dry-etched qubits are more than twice as long as those for wet-etched ones. Additionally, the analysis of time fluctuations of qubit frequencies and relaxation times, which is an effective method to identify the dominant dielectric loss mechanisms, i-ndicates a significantly lower impact of two-level systems in the dry-etched qubits compared to the wet-etched ones.

Recognition of defect types of Arabica coffee beans using image processing

Recognition of defect types of Arabica coffee beans using image processing

A robust defect detection method with a generalization enhancer and cross-modality aggregator for cylinder bores

High-quality cylinder bores in automobile engines enable drivers to respond quickly to emergencies. Automated detection methods are gradually being adopted across various industries. However, uncontrollable factors and improper preservation methods lead to various types of defects on cylinder bores, thereby causing existing high-performance detectors to exhibit not only undesirable generalizability for unseen defect types but also a certain degree of missed detection for defects of seen types, thereby allowing defective cylinder bores to flow into the market. To address these issues, we propose a foundation-model-based robust defect detection method with high generalizability for cylinder bores (RHG-Detector). Specifically, to address unseen defect categories, we propose a generalization enhancer comprising a box filter, a region extractor and a defect discriminator (DeDi) based on a foundation model to extend defect detection from a closed set to an open set. To reduce missed detections, we adopt a cross-modality aggregator to aggregate the detection results from different modalities. Additionally, we collected and annotated challenging defect classification and detection datasets for cylinder bores, named HIT-EngDC (Harbin Institute of Technology Engine defect classification dataset) and HIT-EngDD2 (Engine defect detection dataset-version 2), which cover nearly all types of cylinder bore defects. Extensive experiments on HIT-EngDC and HIT-EngDD2 demonstrate the state-of-the-art performance of RHG-Detector, with a classification accuracy of 92.0 and a mAP@50 (mean average precision under intersection over union = 0.5) score of 45.2, where the latter is increased by ∼6 and ∼3 compared to the corresponding FasterRCNN (faster region-based convolutional neural networks) and YOLOv7 (you only look once) scores, respectively.

Prediction of the Upwarp Buckling Critical Temperature Rise for Longitudinally Connected Slab Track Under Joint Damage State

The joint of longitudinally connected slab track is vulnerable to damage from environmental impacts and repeated train loads. Under high temperature environments, the joint becomes a high risk area for track slab upwarp, which significantly affects the upwarp stability of the track slab and the safe operation of trains. This study employs the arc length approach and a finite element model to investigate the upwarp equilibrium development path of the track slab, the upwarp evolution process of the track slab under the joint damage is further analyzed. Then, the influence of different initial defects on the vertical stability of the track slab is studied. Utilizing dimensional analysis, a general formula for calculating the critical temperature rise of the track slab is proposed. The results are as follows: (1) The entire upwarp process of track slab under joint damage can be divided into three stages: stability, upwarping development, and instability. (2) A nonlinear correlation exists between the upwarp critical temperature rise of the track slab and three types of initial defects. Height defects in narrow joints exert the most significant impact on the critical temperature rise, followed by initial Out-of-straight (initial OOS), with the initial bending shape having the least effect. The complete defect of the narrow joint reduces the upwarp critical temperature rise of the track slab by 53.26°C, a 48.4% reduction. (3) A unified expression, derived from the characteristic parameters of initial defects and dimensional analysis, can more accurately predict the upwarp critical temperature rise of the track slab.