Search Results (1,864)

Currently, in the domain of surface defect detection on hot-rolled strip steel, detecting small-target defects under complex background conditions and effectively balancing computational efficiency with detection accuracy presents a significant challenge. This study proposes CTL-YOLO based on YOLO11, aimed at efficiently and accurately detecting blemishes on the surface of hot-rolled strip steel in industrial applications. Firstly, the CGRCCFPN feature integration network is proposed to achieve multi-scale global feature fusion while preserving detailed information. Secondly, the TVADH Detection Head is proposed to identify defects under complex textured backgrounds. Finally, the LAMP algorithm is used to further compress the network. The proposed algorithm demonstrates excellent performance on the public dataset NEU-DET, achieving a mAP50 of 77.6%, representing a 3.2 percentage point enhancement compared to the baseline algorithm. The GFLOPs is reduced to 2.0, a 68.3% decrease compared to the baseline, and the Params are reduced to 0.40, showing an 84.5% reduction. Additionally, it exhibits strong generalization capabilities on the public dataset GC10-DET. The algorithm can effectively improve detection accuracy while maintaining a lightweight design. Full article

Background: The reconstruction of extensive full-thickness lower eyelid defects constitutes a challenge for plastic surgeons. Various techniques have been described to cater to patients’ specific defect needs, with the aim of achieving the best results. Materials and Methods: We performed a retrospective observational study assessing our experience with a combination of a single-stage procedure consisting of a hard palate graft and a Fricke flap for patients with complex lower lid resections undergoing immediate total reconstruction at our institution. Clinical data, histological type and results, size of tumor, recurrences, and post-operative complications were collected to evaluate outcomes. A Visual Analogue 10-point scale was administered to all patients to assess esthetic and functional outcomes. Results: Seven lower lid reconstructions were performed, with all patients receiving immediate reconstruction. The age of the patients ranged from 55 to 82. Five skin cancers were located on the right side and three on the left side. In all cases, histological diagnosis was non-melanoma skin cancers. The mean size of the tumor was 1.7 × 1.7. In all patients, negative surgical margins were obtained. All patients underwent 24-month follow up. No immediate complication from surgery was recorded within the first 30 days. During follow-up, lower lid ectropion was observed in one patient due to the development of a retracting scar. No local cancer recurrence or nodal metastasis were detected until 2 years follow-up. In only one case, adjuvant therapy was required. The aesthetic results were deemed satisfactory by all patients. Conclusions: According to our experience, the combination of a Fricke flap and hard palate graft is an excellent option for total lower eyelid reconstruction, with low morbidity and favorable outcomes, even in elderly and frail patients where satisfactory results were achieved in a single-stage procedure and short operative times. Full article

The present study offers an experimental investigation into the welding of Cu–Nb wire using upset resistance welding. The aim is to examine the structure, as well as the electrical and mechanical properties, of Cu–Nb conductor joints produced by this method, which are intended for use in coils in pulsed magnetic systems. Analysis of the joint structure revealed that it was free from welding defects. The welded joint demonstrated a negligible change in electrical resistance while retaining sufficient ultimate strength and plasticity comparable to the base material. The tensile strength of the welded sample was found to be 620 MPa. The heat-affected zone is narrow, and the heating temperature is lower than the melting point of the composite material. Therefore, welding occurs in the solid phase without remelting the Cu–Nb composite wire or destroying its unique microstructure. Thus, upset welding is a promising technology for use in solenoid terminal connections with external electrical circuits that are not directly exposed to the high magnetic or tensile forces generated inside a solenoid of a pulsed magnet system. Full article

Introduction: Cephalometric analysis is an essential tool used in orthodontic diagnosis and treatment planning. Aim: The aim of this study was to compare the measurement reliabilities (repeatability and reproducibility) of the Tau and Yen angles and compare them to the results obtained for the ANB angle. Methods: Repeatability and reliability assessments for the seven points (N, A, B, S, W, M, G) used in the analysis of ANB, Yen and Tau angles were performed twice with an interval of 7 days by 22 orthodontists. The measurement results for ANB, Yen and Tau angles were assessed using the Bland–Altman formula, Dahlberg formula, intraclass correlation coefficients (ICCs), R² coefficients and R&R. In order to assess the number of individual skeletal classes of sagittal discrepancy, the Pearson chi-squared test was used. With common parameters of df = 4, p < 0001, for the ANB angle, the result was χ² = 9104; for the Tau angle, χ² = 4556; and for the Yen angle, χ² = 4207. In order to determine the inter-rater reliability based on two-way ANOVA analysis without repetitions, the ICC (2,2) was used. The ICC (2,2) index at the 95% confidence level was 0.998 for the ANB angle, 0.997 for Tau and 0.998 for Yen. High values of the ICC index close to 1 indicate the agreement of the measurements and their high reliability. Results: The orthodontists in the study measured sagittal discrepancy significantly more accurately using the ANB angle compared to the Yen and Tau angles. Using a Bland–Altman plot, the bias and range of agreement within which 95% of the differences between measurements were accounted for were determined. For the ANB angle, the mean difference between measurements was 0.07 with a confidence interval of −1.55 to +1.69; for the Tau angle, the mean difference between measurements was 0.19 with a confidence interval of −2.92 to 3.30; and for the Yen angle, the mean difference was 0.09 with a confidence interval of −2.71 to +2.89. Using regression analysis, the measurements were assessed using the R2 index, which for the ANB angle was 0.952 (p < 0.001); for the Tau angle, R2 = 0.928 (p < 0.001), and for the Yen angle, R2 = 0.942 (p < 0.001). Conclusions: The obtained results of the assessment of the ANB, Tau and Yen angles confirm the thesis of the highest reliability, including repeatability and reproducibility, in the assessment of sagittal discrepancy in orthodontic diagnostics using the ANB angle, previously considered the gold standard. One of the basic factors attributed to the poorer repeatability and reproducibility of Tau and Yen measurements is human error related to the precision of determining new anthropometric points. Further studies to assess the usefulness of using the new Tau and Yen angle measurements in orthodontic diagnostics for sagittal discrepancy should be correlated with other measurements used so far, depending on the type of defects in the vertical dimension. It is necessary to consider enlarging the study group and performing longitudinal studies. Full article

Additive manufacturing (AM) offers advantages such as design flexibility and reduced production times, but defects like voids impact mechanical performance and limit its broader adoption. This study quantitatively examines the relationship between void characteristics (volume fraction, distribution, and size) and mechanical properties in both linear and non-linear geometries, represented by a dogbone model and an end-use component, respectively. Samples were produced using Fused Filament Fabrication (FFF) with varying overlap levels to control void content. As the overlap increased from 0% to 99%, voids transitioned from large linear gaps to smaller point-shaped voids. In non-linear geometry, void reduction from 12% to 2% led to a threefold improvement in mechanical response, while in dogbone samples, voids decreased from 12% to nearly 0%, improving the elastic modulus by only 1.5 times. This disparity is due to differences in void distribution, as voids in non-linear geometries affect both margins and internal layers, significantly influencing structural integrity. The findings highlight the importance of the void location in determining mechanical performance and emphasize the limitations of using linear dogbone models to assess void–property relationships in complex 3D-printed structures. Full article

Myelodysplastic syndromes represent a group of hematological neoplastic diseases caused by defective stem cells causing cytopenia and abnormal hematopoiesis. More than 30% of myelodysplastic syndrome cases develop into acute myeloid leukemia. An analysis of bone marrow samples, peripheral blood smears, multiparametric flow cytometry data, and clinical patient information is part of the current, time-consuming, and labor-intensive work up for myelodysplastic syndromes. Nowadays, clinical biomedical research has been transformed by the advent of artificial intelligence, specifically machine learning. Artificial intelligence (AI) can improve risk assessment and diagnosis, as well as boost the precision of clinical outcome prediction and illness classification. Algorithms based on artificial intelligence may be potentially helpful in discovering new needs for myelodysplastic syndrome-affected patients, choosing treatment and assessing minimal residual disease. In this review, we seek to identify the primary mechanisms and uses of artificial intelligence in myelodysplastic syndrome, pointing out its advantages and disadvantages while discussing the possible benefits of using AI pipelines in a therapeutic setting. Full article

Accurate and rapid detection of potato surface defects is crucial for advancing intelligent potato sorting. To elevate detection accuracy as well as shorten the computational load of the model, this paper proposes a lightweight Flaw-YOLOv5s algorithm for potato surface defect detection. Firstly, Depthwise Separable Convolution (DWConv) is used to displace the original Conv in the YOLOv5s network, aiming to reduce computational burden and parameters. Then, the SPPF in the backbone network is replaced by SPPELAN, which combines SPP with ELAN to enable the model to perform multi-scale pooling and feature extraction, optimizing detection capacity for small targets in potatoes. Finally, the lightweight convolution PConv is used to introduce a new structure, CSPC, to substitute for the C3 in the benchmark network, which decreases redundant computations and reduces the model parameters, achieving a lightweight network model. Experimental results demonstrate that the Flaw-YOLOv5s algorithm obtains a mean Average Precision (mAP) of 95.6%, with a precision of 94.6%, representing, respectively, an improvement of 1.6 and 1.8 percentage points over the YOLOv5s network. With only 4.33 million parameters, this lightweight and efficient model satisfies the requirements for detecting surface defects in potatoes. This research provides a reference for the online detection of potato surface defects and deployment on mobile devices. Full article

Si₃N₄ ceramics and composites stand out for their exceptional mechanical and thermal properties. Compared with conventional ceramic forming processes, 3D printing via vat photopolymerization not only ensures high geometric precision but also improves the forming efficiency and strength of green body. Nevertheless, the grayish appearance of Si₃N₄ and its relatively high refractive index can adversely affect the photocuring behavior in ceramic slurries. The primary objectives focus on enhancing the curing performance and rheological properties of slurries, minimizing defects during post-processing, and improving the relative density and mechanical properties of Si₃N₄ ceramics. Key advancements include slurry optimization via refractive index matching, biomodal particle gradation and surface modification, while the integration of whisker/fiber additions or polymer-derived ceramic strategies enhances mechanical properties. In addition, controlling the atmosphere and heating rate of the post-processing innovations can achieve a relative density of more than 95%. This paper introduces the mechanisms of vat photopolymerization and then summarizes the strategies for improving Si₃N₄ ceramic slurries as well as controlling the printing and debinding/sintering processes. It further highlights the ways in which different approaches can be used to enhance the properties of Si₃N₄ slurries and ceramic parts. Finally, applications of Si₃N₄ ceramics and composites via vat photopolymerization in various fields such as aviation, aerospace, energy, electronics, chemical processes, and biomedical implants are also presented to point out future opportunities and challenges. Full article

The role of notch stress and surface defects on fatigue crack initiation and small-crack propagation behavior has been investigated using groove simulation specimens. The naturally initiated small-crack growth tests have been performed on a FGH4099 superalloy at 500 °C and 700 °C. The findings indicate that elevated testing temperature significantly reduced the proportion of fatigue crack initiation life, with a less pronounced effect on the proportion of life for cracks to grow to First Engineering Crack size. Competing crack initiation modes were observed in the fatigue test of groove simulation specimens. The location of maximum principal stress was dominant fatigue crack initiation sites, and for specimens with surface inclusions, the defect location can also serve as a crack initiation site. Furthermore, crack initiation modes were found to have a more pronounced effect on the small-crack growth rate. A turning point observed in the crack growth rate curves for specimens with multi-site crack initiation was attributed to crack shielding and subsequent coalescence. Full article

Chromium-carbide-based cermets have been widely exploited for a number of applications, particularly in petroleum engineering, the metallurgical industry, and aerospace areas, due to their unique properties, such as high hardness and melting point, excellent oxidation, and wear resistance at elevated temperatures. However, the defects of the bulk Cr₃C₂-Ni cermets are their greater brittleness and lower strength at room temperature. In order to increase the strength and extend the service life of this material, researchers have carried out many explorations of the preparation technology and composition optimization. This paper reviewed the preparation process of bulk Cr₃C₂-Ni cermets. In addition, the influence of different elements’ addition on the microstructural, mechanical, and wear properties of the cermets were systematically reported. Furthermore, the industrial applications of Cr₃C₂-NiCr coatings and the prospects for their future development are also introduced. Full article

In this paper, an adaptive iterative Fourier technique (AIFT) algorithm is developed for the synthesis of multiple circular/elliptical beams with low sidelobe levels (SLLs) through phase-only optimization. The key innovation of the AIFT algorithm is the introduction of an elliptical beam model, which facilitates the adaptive determination of main beam regions and offers additional flexibility in controlling pencil beam shapes. Unlike conventional IFT-based algorithms, the AIFT algorithm eliminates the need for prior knowledge of main beam regions and avoids repetitive adjustments of sidelobe correction thresholds. This not only simplifies the configuration process but also prevents the generation of defective radiation patterns. Extensive synthesis experiments with different beam numbers, distributions, and ellipticities demonstrate that the elliptical beam model consistently outperforms its circular counterpart in multibeam scenarios, achieving lower SLL and higher directivity. These advantages are particularly pronounced in asymmetrical beam distributions, highlighting the elliptical beam’s superior potential for reducing SLLs of multi-spot-beam patterns and offering new insights for advancing the performance of point-to-multi-point communication systems. Full article

The aim of almost every production firm is to gain maximum profit along with customer satisfaction. The formation of imperfect products is an obvious process in a production system, which is not a good thing from a business point of view. This paper considers an inventory model for an imperfect production system. All the imperfect products are assumed to be reworkable. An investment occurs for in-process inspection to reduce the rate of formation of imperfect items. A comparison is performed with a production system without in-process inspection to demonstrate the effectiveness of the model. The study shows that the implementation of in-process inspection significantly reduces the total cost of the system as compared to a production system without in-process inspection. The results obtained show that the use of in-process inspection can reduce the total cost by up to 9.3%. Moreover, reducing the formation of defective items saves energy as well as resources. In addition, to reduce carbon emissions, a penalty is implemented on carbon emissions caused by manufacturing, reworking, disposal, and indirect emissions caused by the transportation of disposed items to the treatment facility. As everyone should now be concerned about the environment, green technology is implemented to reduce the amount of carbon emissions to some extent. A classical optimization technique is used to achieve decision variables, i.e., optimal production quantity (Q), fraction of profit invested in in-process inspection ($P_f$), and green technology investment (G), such that the total cost of the system is minimized. A sensitivity analysis is performed to determine the effects of various parameters on the decision variables and total cost. Maple 18 and Mathematica 11 software are used for mathematical work and graphical representation. Full article

In induction motor bearings, distributed faults are prevalent, often resulting from factors such as inadequate lubrication and particle contamination. Unlike localized faults, distributed faults produce complex and unpredictable motor signal behaviors. Although existing research predominantly addresses localized faults in mains-fed motors, particularly single-point defects, a comprehensive investigation into particle contamination in bearings of inverter-fed motors is essential for a more accurate understanding of real-world bearing issues. This paper conducts a comparative analysis of vibration, stator current, speed, and acoustic signals to detect particle contamination through signal analysis across three domains: time, frequency, and time-frequency. These domains are analyzed to assess and compare the characteristics of each monitored signal in the context of bearing wear detection. The data were collected from both steady-state and startup transients of an induction motor controlled by a variable frequency drive. The experimental results highlight the most significant characteristics of each monitored signal, evaluated across the different domains of analysis. The primary conclusion indicates that, in inverter-fed motors, sound and vibration signals exhibit abnormal levels when the bearing is damaged but the related-fault signature becomes complicated. Additionally, the findings demonstrate that the analysis of startup stator current and speed signals presents the potential to detect distributed bearing damage in inverter-fed induction motors. Full article

Surface defects in magnetic tiles pose significant challenges to the performance and reliability of permanent magnet motors. Traditional defect detection methods, including visual inspection and 2D imaging, are limited by subjectivity, resolution constraints, and a lack of depth information, making precise defect quantification challenging. To address this challenge, this study explores a defect detection and quantitative evaluation framework based on high-resolution 3D laser scanning technology. Our approach integrates point cloud acquisition with luminance and point cloud mapping (LPM) to enhance defect visualization. Furthermore, we introduce an adaptive neighborhood selection method based on information entropy, enabling accurate normal vector and curvature estimation while reducing reliance on manual parameter tuning. Even when the point cloud density decreases to 40%, the mean estimation error and root-mean-square error remain within 3°. By leveraging single-frame and multi-frame point cloud fitting, our method transitions from coarse defect extraction to fine refinement, enhancing detection precision. To further improve accuracy and minimize false negatives, we apply region-growing techniques for defect region completion. Experimental results indicate that our method can reliably detect surface defects as small as 0.07 mm², achieving an average precision of 93.91%, a recall of 95.97%, and an F1 of 94.91%. Compared to conventional 2D image-based methods, our method offers superior defect quantification, lower computational costs, and minimal hardware requirements, making it highly suitable for real-time online defect detection in industrial applications. Full article

Software testing identifies potential errors and defects in software. A crucial component of software testing is integration testing, and the generation of class integration test orders (CITOs) is a critical topic in integration testing. The research shows that search-based algorithms can solve this problem effectively. As a novel search-based algorithm, the sparrow search algorithm (SSA) is good at finding the optimal to optimization problems, but it has drawbacks like weak population variety later on and the tendency to easily fall into the local optimum. To overcome its shortcomings, a modified sparrow search algorithm (MSSA) is developed and applied to the CITO generation issue. The algorithm is initialized with a good point set strategy, which distributes the sparrows evenly in the solution space. Then, the discoverer learning strategy of Brownian motion is introduced and the Levy flight is utilized to renew the positions of the followers, which balances the global search and local search of the algorithm. Finally, the optimal solution is subjected to random wandering to increase the probability of the algorithm jumping out of the local optimum. Using the overall stubbing complexity as a fitness function to evaluate different class test sequences, experiments are conducted on open-source Java systems, and the experimental results demonstrate that the MSSA generates test orders with lower stubbing cost in a shorter time than other novel intelligent algorithms. The superiority of the proposed algorithm is verified by five evaluation indexes: the overall stubbing complexity, attribute complexity, method complexity, convergence speed, and running time. The MSSA has shown significant advantages over the BSSA in all aspects. Among the nine systems, the total overall stubbing complexity of the MSSA is 13.776% lower than that of the BSSA. Total time is reduced by 23.814 s. Full article