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Comparison of three fundus inspection methods during phacoemulsification in diabetic white cataract
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作者 Shu Su Jian Wu +3 位作者 Min Ji Yu Guan Yao Shen Huai-Jin Guan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第11期1782-1788,共7页
AIM:To investigate whether Wild Field Imaging System(WFIS SW-8000),25G endoilluminator,and intraoperative optical coherence tomography(iOCT)can perform realtime screening and diagnosing in patients with suspicious dia... AIM:To investigate whether Wild Field Imaging System(WFIS SW-8000),25G endoilluminator,and intraoperative optical coherence tomography(iOCT)can perform realtime screening and diagnosing in patients with suspicious diabetic retinopathy(DR)during phacoemulsification,especially in cases of white cataract.METHODS:A cross-sectional study was carried out.A total of 204 dense diabetic cataractous eyes of 204 patients with suspected DR treated from April 2020 to March 2021 were included.Phacoemulsification combined with intraocular lens implantation was performed.Following the removal of the lens opacity,the 25G endoilluminator,fundus photography,and iOCT were performed successively.Optical coherence tomography(OCT)and/or fundus fluorescein angiography(FFA)were used to verify the fundus findings postoperatively.Intraoperative and postoperative results were compared to verify the accuracy of intraoperative diagnosis in each group.RESULTS:Intraoperative and postoperative examinations revealed 58 and 62 eyes with DR,respectively(positive rate,28.43%and 30.39%,respectively).During the phacoemulsification,WFIS SW-8000 detected 44 eyes with DR(the detection rate,70.97%);25G endo-illuminator found 56 eyes with DR(the detection rate,90.32%);iOCT found 46 eyes with DR(the detection rate,74.19%);and 58 eyes with DR were found by combining the three methods(the detection rate,93.55%).There were statistically significant differences in the diagnostic sensitivity for DR among the methods(χ^(2)=16.36,P=0.001).CONCLUSION:WFIS SW-8000,25G endo-illuminator,iOCT,and especially their combination can be used to inspect the fundus and detect DR intraoperatively;they are helpful for the timely diagnosis and treatment of DR in patients with dense cataract. 展开更多
关键词 diabetic white cataract fundus inspection PHACOEMULSIFICATION diabetic retinopathy
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A Railway Fastener Inspection Method Based on Abnormal Sample Generation
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作者 Shubin Zheng Yue Wang +3 位作者 Liming Li Xieqi Chen Lele Peng Zhanhao Shang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期565-592,共28页
Regular fastener detection is necessary to ensure the safety of railways.However,the number of abnormal fasteners is significantly lower than the number of normal fasteners in real railways.Existing supervised inspect... Regular fastener detection is necessary to ensure the safety of railways.However,the number of abnormal fasteners is significantly lower than the number of normal fasteners in real railways.Existing supervised inspectionmethods have insufficient detection ability in cases of imbalanced samples.To solve this problem,we propose an approach based on deep convolutional neural networks(DCNNs),which consists of three stages:fastener localization,abnormal fastener sample generation based on saliency detection,and fastener state inspection.First,a lightweight YOLOv5s is designed to achieve fast and precise localization of fastener regions.Then,the foreground clip region of a fastener image is extracted by the designed fastener saliency detection network(F-SDNet),combined with data augmentation to generate a large number of abnormal fastener samples and balance the number of abnormal and normal samples.Finally,a fastener inspection model called Fastener ResNet-8 is constructed by being trained with the augmented fastener dataset.Results show the effectiveness of our proposed method in solving the problem of sample imbalance in fastener detection.Qualitative and quantitative comparisons show that the proposed F-SDNet outperforms other state-of-the-art methods in clip region extraction,reaching MAE and max F-measure of 0.0215 and 0.9635,respectively.In addition,the FPS of the fastener state inspection model reached 86.2,and the average accuracy reached 98.7%on 614 augmented fastener test sets and 99.9%on 7505 real fastener datasets. 展开更多
关键词 Railway fastener sample generation inspection model deep learning
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Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality
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作者 Zhen-Hua Zhang Dan Ling +2 位作者 Qin-Xin Yang Yan-Chao Feng Jing Xiu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2139-2153,共15页
Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction sustainably.This study is conducted using a tripartite evolutionary game model to explore ... Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction sustainably.This study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each other.The research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI increases.When the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary game.Moreover,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy appears.This study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy. 展开更多
关键词 Central environmental protection inspection Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction
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Distributed Resource Allocation in Dispersed Computing Environment Based on UAV Track Inspection in Urban Rail Transit
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作者 Tong Gan Shuo Dong +1 位作者 Shiyou Wang Jiaxin Li 《Computers, Materials & Continua》 SCIE EI 2024年第7期643-660,共18页
With the rapid development of urban rail transit,the existing track detection has some problems such as low efficiency and insufficient detection coverage,so an intelligent and automatic track detectionmethod based on... With the rapid development of urban rail transit,the existing track detection has some problems such as low efficiency and insufficient detection coverage,so an intelligent and automatic track detectionmethod based onUAV is urgently needed to avoid major safety accidents.At the same time,the geographical distribution of IoT devices results in the inefficient use of the significant computing potential held by a large number of devices.As a result,the Dispersed Computing(DCOMP)architecture enables collaborative computing between devices in the Internet of Everything(IoE),promotes low-latency and efficient cross-wide applications,and meets users’growing needs for computing performance and service quality.This paper focuses on examining the resource allocation challenge within a dispersed computing environment that utilizes UAV inspection tracks.Furthermore,the system takes into account both resource constraints and computational constraints and transforms the optimization problem into an energy minimization problem with computational constraints.The Markov Decision Process(MDP)model is employed to capture the connection between the dispersed computing resource allocation strategy and the system environment.Subsequently,a method based on Double Deep Q-Network(DDQN)is introduced to derive the optimal policy.Simultaneously,an experience replay mechanism is implemented to tackle the issue of increasing dimensionality.The experimental simulations validate the efficacy of the method across various scenarios. 展开更多
关键词 UAV track inspection dispersed computing resource allocation deep reinforcement learning Markov decision process
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Calibration of CO and CO2 Monitors Used in Periodic Inspection of Vehicles at Fixed Stations for Environmental Control
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作者 Adel Bassuoni Shehata Abdulrahman Rashed Al Askar +2 位作者 Najjy Hamad Al Yami Abdullah Suleiman Al Owaysi Sultan K. Alharbi 《Green and Sustainable Chemistry》 2024年第2期29-41,共13页
Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuri... Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuring the quantitative assessment of emissions for informed decisions on environmental treatments. This paper describes a method for the calibration of CO/CO<sub>2</sub> monitors used for periodic inspections of vehicles in cites. The calibration was performed in the selected ranges: 900 - 12,000 µmol/mol for CO and 2000 - 20,000 µmol/mol for CO<sub>2</sub>. The traceability of the measurement results to the SI units was ensured by using certified reference materials from CO/N<sub>2</sub> and CO<sub>2</sub>/N<sub>2</sub> primary gas mixtures. The method performance was evaluated by assessing its linearity, accuracy, precision, bias, and uncertainty of the calibration results. The calibration data exhibited a strong linear trend with R² values close to 1, indicating an excellent fit between the measured values and the calibration lines. Precision, expressed as relative standard deviation (%RSD), ranged from 0.48 to 4.56% for CO and from 0.97 to 3.53% for CO<sub>2</sub>, staying well below the 5% threshold for reporting results at a 95% confidence level. Accuracy measured as percent recovery, was consistently high (≥ 99.1%) for CO and ranged from 84.90% to 101.54% across the calibration range for CO<sub>2</sub>. In addition, the method exhibited minimal bias for both CO and CO<sub>2</sub> calibrations and thus provided a reliable and accurate approach for calibrating CO/CO<sub>2</sub> monitors used in vehicle inspections. Thus, it ensures the effectiveness of exhaust emission control for better environment. 展开更多
关键词 MONITORS Periodic inspection CO/CO2 Calibration LINEARITY Precision Accuracy
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Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation
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作者 Dingping Chen Zhiheng Zhu +1 位作者 Jinyang Fu Jilin He 《Computers, Materials & Continua》 SCIE EI 2024年第4期1679-1703,共25页
The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the su... The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road tunnels.We propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-stagedetection method outperforms other state-of-the-art models in crack region localization and detection. Based onour proposedmethod, the images captured on the surface of a road tunnel can complete crack detection at a speed often frames/second, and the detection accuracy can reach 0.25 mm, which meets the requirements for maintenanceof an actual project. The designed CA-YOLO V7 network enables precise localization of the area to which a crackbelongs in images acquired under different environmental and lighting conditions in road tunnels. The improvedDeepLab V3+ network based on lightweighting is able to extract crack morphology in a given region more quicklywhile maintaining segmentation accuracy. The established model combines defect localization and segmentationmodels for the first time, realizing pixel-level defect localization and extraction on the surface of road tunnelsin complex environments, and is capable of determining the actual size of cracks based on the physical coordinatesystemafter camera calibration. The trainedmodelhas highaccuracy andcanbe extendedandapplied to embeddedcomputing devices for the assessment and repair of damaged areas in different types of road tunnels. 展开更多
关键词 Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+
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Unmanned Aerial Vehicle Inspection Routing and Scheduling for Engineering Management
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作者 Lu Zhen Zhiyuan Yang +2 位作者 Gilbert Laporte Wen Yi Tianyi Fan 《Engineering》 SCIE EI CAS CSCD 2024年第5期223-239,共17页
Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based solutions.In engineering management,UAV-based inspection has emerged as ... Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based solutions.In engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection techniques.Building on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring rounds.To tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging decisions.The comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale instances.To overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our model.Extensive numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale instances.Sensitivity experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency. 展开更多
关键词 Engineering management Unmanned aerial vehicle inspection routing and scheduling OPTIMIZATION Mixed-integer linear programming model Variable neighborhood search metaheuristic
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A Systematic Review of Computer Vision Techniques for Quality Control in End-of-Line Visual Inspection of Antenna Parts
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作者 Zia Ullah Lin Qi +2 位作者 E.J.Solteiro Pires Arsénio Reis Ricardo Rodrigues Nunes 《Computers, Materials & Continua》 SCIE EI 2024年第8期2387-2421,共35页
The rapid evolution of wireless communication technologies has underscored the critical role of antennas in ensuring seamless connectivity.Antenna defects,ranging from manufacturing imperfections to environmental wear... The rapid evolution of wireless communication technologies has underscored the critical role of antennas in ensuring seamless connectivity.Antenna defects,ranging from manufacturing imperfections to environmental wear,pose significant challenges to the reliability and performance of communication systems.This review paper navigates the landscape of antenna defect detection,emphasizing the need for a nuanced understanding of various defect types and the associated challenges in visual detection.This review paper serves as a valuable resource for researchers,engineers,and practitioners engaged in the design and maintenance of communication systems.The insights presented here pave the way for enhanced reliability in antenna systems through targeted defect detection measures.In this study,a comprehensive literature analysis on computer vision algorithms that are employed in end-of-line visual inspection of antenna parts is presented.The PRISMA principles will be followed throughout the review,and its goals are to provide a summary of recent research,identify relevant computer vision techniques,and evaluate how effective these techniques are in discovering defects during inspections.It contains articles from scholarly journals as well as papers presented at conferences up until June 2023.This research utilized search phrases that were relevant,and papers were chosen based on whether or not they met certain inclusion and exclusion criteria.In this study,several different computer vision approaches,such as feature extraction and defect classification,are broken down and analyzed.Additionally,their applicability and performance are discussed.The review highlights the significance of utilizing a wide variety of datasets and measurement criteria.The findings of this study add to the existing body of knowledge and point researchers in the direction of promising new areas of investigation,such as real-time inspection systems and multispectral imaging.This review,on its whole,offers a complete study of computer vision approaches for quality control in antenna parts.It does so by providing helpful insights and drawing attention to areas that require additional exploration. 展开更多
关键词 Computer vision end-of-line visual inspection of antenna parts machine learning algorithms image processing techniques deep learning models
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High-speed railway track components inspection framework based on YOLOv8 with high-performance model deployment
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作者 Youzhi Tang Yu Qian 《High-Speed Railway》 2024年第1期42-50,共9页
Railway inspection poses significant challenges due to the extensive use of various components in vast railway networks,especially in the case of high-speed railways.These networks demand high maintenance but offer on... Railway inspection poses significant challenges due to the extensive use of various components in vast railway networks,especially in the case of high-speed railways.These networks demand high maintenance but offer only limited inspection windows.In response,this study focuses on developing a high-performance rail inspection system tailored for high-speed railways and railroads with constrained inspection timeframes.This system leverages the latest artificial intelligence advancements,incorporating YOLOv8 for detection.Our research introduces an efficient model inference pipeline based on a producer-consumer model,effectively utilizing parallel processing and concurrent computing to enhance performance.The deployment of this pipeline,implemented using C++,TensorRT,float16 quantization,and oneTBB,represents a significant departure from traditional sequential processing methods.The results are remarkable,showcasing a substantial increase in processing speed:from 38.93 Frames Per Second(FPS)to 281.06 FPS on a desktop system equipped with an Nvidia RTX A6000 GPU and from 19.50 FPS to 200.26 FPS on the Nvidia Jetson AGX Orin edge computing platform.This proposed framework has the potential to meet the real-time inspection requirements of high-speed railways. 展开更多
关键词 High-speed railway Track inspection Computer vision Deep learning Edge computing Real-time decision making
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A path planning method for robot patrol inspection in chemical industrial parks
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作者 王伟峰 YANG Ze +1 位作者 LI Zhao ZHAO Xuanchong 《High Technology Letters》 EI CAS 2024年第2期109-116,共8页
Safety patrol inspection in chemical industrial parks is a complex multi-objective task with multiple degrees of freedom.Traditional pointer instruments with advantages like high reliability and strong adaptability to... Safety patrol inspection in chemical industrial parks is a complex multi-objective task with multiple degrees of freedom.Traditional pointer instruments with advantages like high reliability and strong adaptability to harsh environment,are widely applied in such parks.However,they rely on manual readings which have problems like heavy patrol workload,high labor cost,high false positives/negatives and poor timeliness.To address the above problems,this study proposes a path planning method for robot patrol in chemical industrial parks,where a path optimization model based on improved iterated local search and random variable neighborhood descent(ILS-RVND)algorithm is established by integrating the actual requirements of patrol tasks in chemical industrial parks.Further,the effectiveness of the model and algorithm is verified by taking real park data as an example.The results show that compared with GA and ILS-RVND,the improved algorithm reduces quantification cost by about 24%and saves patrol time by about 36%.Apart from shortening the patrol time of robots,optimizing their patrol path and reducing their maintenance loss,the proposed algorithm also avoids the untimely patrol of robots and enhances the safety factor of equipment. 展开更多
关键词 path planning robot patrol inspection iterated local search and random variableneighborhood descent(ILS-RVND)algorithm
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From manual to automated fabric inspection
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《China Textile》 2024年第2期40-41,共2页
Uster,Switzerland,28th March 2024–Uster Technologies offers a flexible solution to upgrade fabric inspection from manual to automated.Integration in existing production lines is quick and easy,and the data flow also ... Uster,Switzerland,28th March 2024–Uster Technologies offers a flexible solution to upgrade fabric inspection from manual to automated.Integration in existing production lines is quick and easy,and the data flow also brings extra benefits.It means fabric producers can significantly improve their yield with fast,accurate quality monitoring. 展开更多
关键词 USTER inspection FABRIC
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Analysis of the Application of Bridge Rapid Inspection and Evaluation Technology
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作者 Jiang Feng Qing Yang 《Journal of Architectural Research and Development》 2024年第1期49-55,共7页
Rapid bridge inspection and evaluation mainly uses information technology to test the quality of bridge infrastructure and structures,integrates the test results with the existing management system,completes the bridg... Rapid bridge inspection and evaluation mainly uses information technology to test the quality of bridge infrastructure and structures,integrates the test results with the existing management system,completes the bridge status assessment,establishes information management files to provide bridge disease problem inspection and analysis,and provides support for the application of disposal measures.This paper briefly discusses the necessity of applying rapid inspection and evaluation technology and analyzes the bridge’s rapid inspection and evaluation content,inspection system,and application process.We look forward to the future application prospects of this technology and supporting those in this field. 展开更多
关键词 BRIDGE Rapid inspection EVALUATION INFORMATIZATION
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Defect Inspection Technology for Steel Truss Suspension Bridges
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作者 Bo Liu Xu Meng +1 位作者 Ji Li Zhi Tu 《Journal of World Architecture》 2024年第2期12-16,共5页
Steel truss suspension bridges are prone to developing defects after prolonged use.These defects may include corrosion of the main cable or the steel truss.To ensure the normal and safe functioning of the suspension b... Steel truss suspension bridges are prone to developing defects after prolonged use.These defects may include corrosion of the main cable or the steel truss.To ensure the normal and safe functioning of the suspension bridge,it is necessary to inspect for defects promptly,understand the cause of the defect,and locate it through the use of inspection technology.By promptly addressing defects,the suspension bridge’s safety can be ensured.The author has analyzed the common defects and causes of steel truss suspension bridges and proposed specific inspection technologies.This research is intended to aid in the timely discovery of steel truss suspension bridge defects. 展开更多
关键词 Steel truss suspension bridge DEFECT inspection technology
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Utility of single-incision totally extraperitoneal inguinal hernia repair with intraperitoneal inspection 被引量:7
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作者 Masateru Yamamoto Takashi Urushihara Toshiyuki Itamoto 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2017年第12期264-269,共6页
AIM To study the utility of single-incision totally extraperitoneal inguinal hernia repair with intraperitoneal inspection.METHODS A 2 cm transverse skin incision was made in the umbilicus, extending to the intraperit... AIM To study the utility of single-incision totally extraperitoneal inguinal hernia repair with intraperitoneal inspection.METHODS A 2 cm transverse skin incision was made in the umbilicus, extending to the intraperitoneal cavity. Carbon dioxide was insufflated followed by insertion of laparoscope to observe the intraperitoneal cavity. The type of hernia was diagnosed and whether there was the presence of intestinal incarceration was confirmed. When an intestinal incarceration in the hernia sac was found, the forceps were inserted through the incision site and the intestine was returned to the intraperitoneal cavity without increasing the number of trocars. Once the peritoneum was closed, totally extraperitoneal inguinal hernia repair was performed, and finally, intraperitoneal observation was performed to reconfirm the repair.RESULTS Of the 75 hernias treated, 58 were on one side, 17 were on both sides, and 10 were recurrences. The respective median operation times for these 3 groups of patients were 100 min(range, 66 to 168), 136 min(range, 114 to 165), and 125 min(range, 108 to 156), with median bleeding amounts of 5 g(range, 1 to 26), 3 g(range, 1 to 52), and 5 g(range, 1 to 26), respectively. Intraperitoneal observation showed hernia on the opposite side in 2 cases, intestinal incarceration in 3 cases, omental adhesion into the hernia sac in 2 cases, severe postoperative intraperitoneal adhesions in 2 cases, and bladder protrusion in 1 case. There was only 1 case of recurrence.CONCLUSION Single-incision totally extraperitoneal inguinal hernia repair with intraperitoneal inspection makes hernia repairs safer and reducing postoperative complications. The technique also has excellent cosmetic outcomes. 展开更多
关键词 Inguinal hernia Intestinal incarceration totally extraperitoneal inguinal hernia repair Intraperitoneal inspection Single incision
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Three-axis magnetic flux leakage in-line inspection simulation based on finite-element analysis 被引量:4
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作者 冯健 张峻峰 +2 位作者 卢森骧 王宏阳 马瑞泽 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期531-536,共6页
With the increase of pipelines, corrosion leakage accidents happen frequently. Therefore, nondestructive testing technology is important for ensuring the safe operation of the pipelines and energy mining. In this pape... With the increase of pipelines, corrosion leakage accidents happen frequently. Therefore, nondestructive testing technology is important for ensuring the safe operation of the pipelines and energy mining. In this paper, the structure and principle of magnetic flux leakage (MFL) in-line inspection system is introduced first. Besides, a mathematic model of the system according to the ampere circuit rule, flux continuity theorem, and column coordinate transform is built, and the magnetic flux density in every point of space is calculated based on the theory of finite element analysis. Then we analyze and design the disposition of measurement section probes and sensors combining both three-axis MFL in-line inspection and multi-sensor fusion technology. Its advantage is that the three-axis changes of magnetic flux leakage field are measured by the multi-probes at the same time, so we can determine various defects accurately. Finally, the theory of finite element analysis is used to build a finite element simulation model, and the relationship between defects and MFL inspection signals is studied. Simulation and experiment results verify that the method not only enhances the detection ability to different types of defects but also improves the precision and reliability of the inspection system. 展开更多
关键词 magnetic flux leakage in-line inspection multi-sensor data fusion sensor disposition finite element analysis
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Surface form inspection with contact coordinate measurement:a review 被引量:4
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作者 Yijun Shen Jieji Ren +3 位作者 Nuodi Huang Yang Zhang Xinquan Zhang Limin Zhu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第2期119-147,共29页
Parts with high-quality freeform surfaces have been widely used in industries,which require strict quality control during the manufacturing process.Among all the industrial inspection methods,contact measurement with ... Parts with high-quality freeform surfaces have been widely used in industries,which require strict quality control during the manufacturing process.Among all the industrial inspection methods,contact measurement with coordinate measuring machines or computer numerical control machine tool is a fundamental technique due to its high accuracy,robustness,and universality.In this paper,the existing research in the contact measurement field is systematically reviewed.First,different configurations of the measuring machines are introduced in detail,which may have influence on the corresponding sampling and inspection path generation criteria.Then,the entire inspection pipeline is divided into two stages,namely the pre-inspection and post-inspection stages.The typical methods of each sub-stage are systematically overviewed and classified,including sampling,accessibility analysis,inspection path generation,probe tip radius compensation,surface reconstruction,and uncertainty analysis.Apart from those classical research,the applications of the emerging deep learning technique in some specific tasks of measurement are introduced.Furthermore,some potential and promising trends are provided for future investigation. 展开更多
关键词 freeform surface form inspection contact measurement coordinate measurement on-machine inspection
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Two-Stage Inspection Model Based on a Three-Stage Failure Process
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作者 杨瑞锋 康建设 王广彦 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期215-218,共4页
As the non-periodic inspections are common in practice,a two-stage inspection model based on a three-stage failure process is proposed. The two-stage inspection means that the system is inspected with the first inspec... As the non-periodic inspections are common in practice,a two-stage inspection model based on a three-stage failure process is proposed. The two-stage inspection means that the system is inspected with the first inspection interval T_1 and the second inspection interval T_2. Because of the three color schemes commonly used in industry,three stages are divided by the system lifetime:normal, minor defective and severe defective stages. Upon the failure of the system,replacement is carried out. Maintenance is done once identifying the severe defective stage. However,when the minor defective stage is identified by the second inspection interval T_2,action of halving the subsequent inspection interval is adopted.Otherwise,no action is required. Our objective function is to optimize the inspection intervals so as to minimize the expected cost per unit time. Finally,a numerical example is presented to illustrate the effectiveness of the proposed model. 展开更多
关键词 delay time two-stage inspection three-stage failure process preventive maintenance(PM)
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A New Guide Wave Inspection System Using Three Polarized Transverse Wave EMATs without Any Couplant
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作者 Riichi Murayama 《Journal of Sensor Technology》 2016年第4期110-121,共12页
A guide wave is provided with the characteristic of long range propagation in the axis direction of a pipe, so it is possible to detect many defects over a large pipe area at once. At present, there is a technique to ... A guide wave is provided with the characteristic of long range propagation in the axis direction of a pipe, so it is possible to detect many defects over a large pipe area at once. At present, there is a technique to generate a guide wave using a piezoelectric element (PZT). However, the transverse wave-transducer using PZT needs to require a high viscosity couplant because the transverse wave cannot travel into typical liquid like water or oil. A guide wave inspection system that uses an electromagnetic ultrasonic transducer (EMAT) which does not require any couplant has then been developed to solve this trouble. First, a guide wave into a pipe, L, T and F-mode, can be transmitted and received by a polarized shear horizontal transverse wave propagating to the thickness direction when the vibration direction has been adjusted to the best direction. At next stage, the three EMATs for L, T and F-mode with different polarized vibration directions were piled up to improve the performance at the same position under the permanent magnet to inspect the pipe at the same condition. Next, the system with the EMATs can be confirmed to be able to detect three guide wave modes signal with enough intensity. Finally, the detection performance using the test pipes with any artificial defects has been done by the developed pipe inspection system, and any drilled holes and any notches can be detected. It is indicated that the developed system could be useful in real industrial field. 展开更多
关键词 Guide Wave Transverse Wave EMAT Nondestructive inspection Pipe
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Low-Cost Real-Time Automated Optical Inspection Using Deep Learning and Attention Map
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作者 Yu Shih Chien-Chih Kuo Ching-Hung Lee 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2087-2099,共13页
The recent trends in Industry 4.0 and Internet of Things have encour-aged many factory managers to improve inspection processes to achieve automa-tion and high detection rates.However,the corresponding cost results of... The recent trends in Industry 4.0 and Internet of Things have encour-aged many factory managers to improve inspection processes to achieve automa-tion and high detection rates.However,the corresponding cost results of sample tests are still used for quality control.A low-cost automated optical inspection system that can be integrated with production lines to fully inspect products with-out adjustments is introduced herein.The corresponding mechanism design enables each product to maintain afixed position and orientation during inspec-tion to accelerate the inspection process.The proposed system combines image recognition and deep learning to measure the dimensions of the thread and iden-tify its defects within 20 s,which is lower than the production-line productivity per 30 s.In addition,the system is designed to be used for monitoring production lines and equipment status.The dimensional tolerance of the proposed system reaches 0.012 mm,and a 100%accuracy is achieved in terms of the defect reso-lution.In addition,an attention-based visualization approach is utilized to verify the rationale for the use of the convolutional neural network model and identify the location of thread defects. 展开更多
关键词 Automated optical inspection deep learning real-time inspection ATTENTION
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Automated X-ray Defect Inspection on Occluded BGA Balls Using Hybrid Algorithm
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作者 Ki-Yeol Eom Byungseok Min 《Computers, Materials & Continua》 SCIE EI 2023年第6期6337-6350,共14页
Automated X-ray defect inspection of occluded objects has been an essential topic in semiconductors,autonomous vehicles,and artificial intelligence devices.However,there are few solutions to segment occluded objects i... Automated X-ray defect inspection of occluded objects has been an essential topic in semiconductors,autonomous vehicles,and artificial intelligence devices.However,there are few solutions to segment occluded objects in the X-ray inspection efficiently.In particular,in the Ball Grid Array inspection of X-ray images,it is difficult to accurately segment the regions of occluded solder balls and detect defects inside solder balls.In this paper,we present a novel automatic inspection algorithm that segments solder balls,and detects defects fast and efficiently when solder balls are occluded.The proposed algorithm consists of two stages.In the first stage,the defective candidates or defects are determined through the following four steps:(i)image preprocessing such as noise removal,contrast enhancement,binarization,connected component,and morphology,(ii)limiting the inspec-tion area to the ball regions and determining if the ball regions are occluded,(iii)segmenting each ball region into one or more regions with similar gray values,and(iv)determining whether there are defects or defective candidates in the regions using a weighted sum of local threshold on local variance.If there are defective candidates,the determination of defects is finally made in the following stage.In the second stage,defects are detected using the automated inspection technique based on oblique computed tomography.The 3D precision inspection process is divided into four steps:(i)obtaining 360 projection images(one image per degree)rotating the object from 0 to 360 degrees,(ii)reconstructing a 3D image from the 360 projected images,(iii)finding the center slice of gravity for solder balls from the axial slice images in the z-direction,and getting the inspection intervals between the upper bound and the lower bound from the center slice,and(iv)finally determining whether there are defects in the averaged image of solder balls.The proposed hybrid algorithm is robust for segmenting the defects inside occluded solder balls,and improves the performance of solder ball segmentation and defect detection algorithm.Experimental results show an accuracy of more than 97%. 展开更多
关键词 HYBRID voids BGA X-ray inspection DEFECTS
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