Sewer pipe condition assessment by performing regular inspections is crucial for ensuring the systems’effective operation and maintenance.CCTV(closed-circuit television)is widely employed in North America to examine ...Sewer pipe condition assessment by performing regular inspections is crucial for ensuring the systems’effective operation and maintenance.CCTV(closed-circuit television)is widely employed in North America to examine the internal conditions of sewage pipes.Due to the extensive inventory of pipes and associated costs,it is not practical for municipalities to conduct inspections on each sanitary sewage pipe section.According to the ASCE(American Society of Civil Engineers)infrastructure report published in 2021,combined investment needs for water and wastewater systems are estimated to be$150 billion during 2016-2025.Therefore,new solutions are needed to fill the trillion-dollar investment gap to improve the existing water and wastewater infrastructure for the coming years.ML(machine learning)based prediction model development is an effective method for predicting the condition of sewer pipes.In this research,sewer pipe inspection data from several municipalities are collected,which include variables such as pipe material,age,diameter,length,soil type,slope of construction,and PACP(Pipeline Assessment Certification Program)score.These sewer pipe data exhibit a severe imbalance in pipes’PACP scores,which is considered the target variable in the development of models.Due to this imbalanced dataset,the performance of the sewer prediction model is poor.This paper,therefore,aims to employ oversampling and hyperparameter tuning techniques to treat the imbalanced data and improve the model’s performance significantly.Utility owners and municipal asset managers can utilize the developed models to make more informed decisions on future inspections of sewer pipelines.展开更多
The expected cost per unit of time for a sequential inspection policy is derived. It still has some difficulties to compute an optimal sequential policy numerically, which minimizes the expected cost of a system with ...The expected cost per unit of time for a sequential inspection policy is derived. It still has some difficulties to compute an optimal sequential policy numerically, which minimizes the expected cost of a system with finite number of inspections. This paper gives the algorithm for an optimal inspection schedule and specifies the computing procedure for a Weibull distribution. Using this algorithm, optimal inspection times are computed as a numerical result. Compared with the periodic point inspection, the policies in this paper reduce the cost successfully.展开更多
With the increasing number of vehicles,manual security inspections are becoming more laborious at road checkpoints.To address it,a specialized Road Checkpoints Robot(RCRo)system is proposed,incorporated with enhanced ...With the increasing number of vehicles,manual security inspections are becoming more laborious at road checkpoints.To address it,a specialized Road Checkpoints Robot(RCRo)system is proposed,incorporated with enhanced You Only Look Once(YOLO)and a 6-degree-of-freedom(DOF)manipulator,for autonomous identity verification and vehicle inspection.The modified YOLO is characterized by large objects’sensitivity and faster detection speed,named“LF-YOLO”.The better sensitivity of large objects and the faster detection speed are achieved by means of the Dense module-based backbone network connecting two-scale detecting network,for object detection tasks,along with optimized anchor boxes and improved loss function.During the manipulator motion,Octree-aided motion control scheme is adopted for collision-free motion through Robot Operating System(ROS).The proposed LF-YOLO which utilizes continuous optimization strategy and residual technique provides a promising detector design,which has been found to be more effective during actual object detection,in terms of decreased average detection time by 68.25%and 60.60%,and increased average Intersection over Union(Io U)by 20.74%and6.79%compared to YOLOv3 and YOLOv4 through experiments.The comprehensive functional tests of RCRo system demonstrate the feasibility and competency of the multiple unmanned inspections in practice.展开更多
This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their us...This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).展开更多
Periodical inspections and an age-based preventive replacement( APR) model were proposed based on a two-stage failure process for a single component system. Inspection activities were performed at regular intervals. O...Periodical inspections and an age-based preventive replacement( APR) model were proposed based on a two-stage failure process for a single component system. Inspection activities were performed at regular intervals. Once the system was identified to be at defective state by inspection,a maintenance decision needed to be made that whether to replace the defective system immediately or wait till the preset APR time. So a threshold was introduced into the model and called as inspection-based preventive replacement( IPR) threshold. If the distance from the defect identification point to the APR time was longer than the threshold, a preventive replacement( PR) action was made; otherwise PR action was to wait till the APR time. Two models were proposed and compared,and a numerical example was conducted to illustrate the applicability of the model.展开更多
Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making...Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making it difficult to identify surface defects. In this study,a method for improving the quality of underwater images is proposed.By analyzing the degradation characteristics of underwater detection image,the image enhancement technology is used to improve the color richness of the image,and then the improved dark channel prior(DCP)algorithm is used to restore it. By modifying the estimation formula of transmittance and background light,the correction of insufficient brightness in DCP restored image is realized. The proposed method is compared with other state-of-the-art methods. The results show that the proposed method can achieve higher scores and improve the image quality by correcting the color and restoring local details,thus effectively enhancing the reliability of visual inspection of NPPs.展开更多
This paper covers the safely requirements and inspection methods for insulating components used in electrical accessories by an analyzing the properties of the insulating components used in electrical accessories base...This paper covers the safely requirements and inspection methods for insulating components used in electrical accessories by an analyzing the properties of the insulating components used in electrical accessories based on the standard of IEC 60884.展开更多
The manual visual inspections of façade building defects are posing a high and increasing cost for building asset managers,particularly when inspections delay projects or require asset outages,visits to decommiss...The manual visual inspections of façade building defects are posing a high and increasing cost for building asset managers,particularly when inspections delay projects or require asset outages,visits to decommissioned sites or work within hazardous environments.This paper reports on the development,testing and delivery of a working mobile app prototype to facilitate the inspections and documentation of building facade condition monitoring.The work presented builds upon the development of an online platform for remote building inspection based on the integration of methodologies and tools,including VR(virtual reality),and digital photogrammetry to collect real-time data that support automated decision making.The mobile app:(i)allows the user to import 3D models and 2D building plans;(ii)provides the means of first-person exploration of models via a VR headset;and(iii)captures,records and catalogues images of façade defect types,and the date and time.An inspection case study was used to demonstrate and evaluate the mobile app prototype.The Building Inspector app allows building professionals to manage inspections and to track past and ongoing monitoring of the condition of building façades.展开更多
To develop China’s human rights cause with a people-centered approach,we should pay close attention to the concrete experiences of the general public regarding the protection of human rights.Deepening the research on...To develop China’s human rights cause with a people-centered approach,we should pay close attention to the concrete experiences of the general public regarding the protection of human rights.Deepening the research on the perception of respect for human rights can contribute to a more comprehensive understanding of the practical achievements of the hu man rights cause.Public environmental rights,as a new type of human rights,have become an important aspect of the development of the human rights cause in the new era.The central envi ronmental inspection,as an authoritative and interventionist vertical governance mechanism,promotes the implementation of environmental policies by local Party committees and govern ments and strengthens environmental information disclosure and public participation in environ mental matters.As a result,it contributes to the realization of public environmental rights and stimulates public perception of respect for human rights.Among them,the“look-back inspec tion is an important component of the central environmental inspection,and its implemen tation consolidates and enhances the previous inspection work.An empirical analysis based on the World Values Survey’s data for China indicates that residents in the provinces that have underg one“look-back inspections are more inclined to believe that human rights are adequately re spected compared to residents in the provinces that have not underwent such inspections.It suggests that the advancement and improvement of the central environmental inspection system promote improvements in ecological environment quality and contribute to enhancing the public percep tion of respect for human rights.展开更多
Assume that a target is hidden or lost in one of several possible locations and is to be found by the unmanned aerial vehicle (UAV). A target can be either a hostile object or missing personnel in remote areas. Prior ...Assume that a target is hidden or lost in one of several possible locations and is to be found by the unmanned aerial vehicle (UAV). A target can be either a hostile object or missing personnel in remote areas. Prior probabilities of target locations are known. Inspection operations done by the UAVs are imperfect, namely, probabilities of overlooking the hidden target and probabilities of false alarms exist for any possible location. The UAV has to sequentially inspect the locations so that to find the target with the minimum loss or damage incurred by the target before it is detected subject to a required level of confidence of target identification. A fast (polynomial-time) priority-based algorithm for finding an optimal search strategy is developed.展开更多
Bum-in has been proven effective in identifying and removing defective products before they are delivered to customers.Most existing bum-in models adopt a one-shot scheme,which may not be sufficient enough for identif...Bum-in has been proven effective in identifying and removing defective products before they are delivered to customers.Most existing bum-in models adopt a one-shot scheme,which may not be sufficient enough for identification.Borrowing the idea from sequential inspections for remaining useful life prediction and accelerated lifetime test,this study proposes a sequential degradation-based bum-in model with multiple periodic inspections.At each inspection epoch,the posterior probability that a product belongs to a normal one is updated with the inspected degradation level.Based on the degradation level and the updated posterior probability,a product can be disposed,put into field use,or kept in the test till the next inspection epoch.We cast the problem into a partially observed Markov decision process to minimize the expected total bum-in cost of a product,and derive some interesting structures of the optimal policy.Then,algorithms are provided to find the joint optimal inspection period and number of inspections in steps.A numerical study is also provided to illustrate the effectiveness of our proposed model.展开更多
Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined sp...Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.展开更多
Ⅰ. INTRODUCTION The nondestructive inspection using Compton scattering has many advantages, such as direct displays fast throughput, and easy computer control. Being a supplement to currently available nondestructive...Ⅰ. INTRODUCTION The nondestructive inspection using Compton scattering has many advantages, such as direct displays fast throughput, and easy computer control. Being a supplement to currently available nondestructive inspection methods, it has a specific application in industry. This inspection technique has attracted special attention at home and abroad, therefore, the experimental technology is in rapid progress in recent years. For example, the展开更多
Objective：To study the differences in a special region（SR） corresponding to five internal organs between the young and the elderly and to verify the effectiveness of a developed system for objectifying research in ...Objective：To study the differences in a special region（SR） corresponding to five internal organs between the young and the elderly and to verify the effectiveness of a developed system for objectifying research in colour inspections of Chinese medicine（CICM）.Methods：An image acquisition device imitating daylight to meet the requirement of CICM was designed.Image processing software based on CICM theory was developed.A total of 83 normal people were sampled and assigned to two groups.The first group（Group I）included 30 people with an average age of 24 ±2,and the second group（Group Ⅱ） included 53 people with an average age of 74 ±4.After image processing,the chromaticity of 10 SRs corresponding to five internal organs was calculated.R,G,and B represent the chromaticity of color red,green,and blue,L indicates color brightness,whereas a and b denote red and yellow respectively.The difference between the young and the elderly was analyzed.Results：（1） The chromaticity of each SR corresponding to five organs was obtained.The average R,G,B,L,a,and b of the sample were 194.4,147.6,119.3,65.2,15.5,and 22.3,respectively.（2） The R,G,B,and L of the young were greater than those of the elderly,but the a and b of the young were less than those of the elderly.（3） A statistically significant difference in each SR was found between the young and the elderly（P0.05）.The total differences for the Lung（Fei）,Heart（Xin）,Liver（Gan）,Spleen（Pi）,and Kidney（Shen） were 50%（3/6）,66.7%（4/6）,66.7%（4/6）,83.3%（5/6）,and 91.7%（33/36）,respectively.However,the Kidney SR had the greatest statistical discrepancy.Conclusion：The old Chinese saying that human Kidney deficiency worsens with age was verified by the results.The objectifying system used to examine CICM was effective.Thus,this system may be used as a basis for further research.展开更多
Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industr...Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industry.He graduated as an Engineering Geologist at Delft University of Technology in 2002.After graduation,he performed foundation inspections and vibration monitoring at IFCO foundations and worked as a consultant and researcher at GeoDelft which later became Deltares.展开更多
Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,an...Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection.展开更多
In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and...In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing.展开更多
To improve the efficiency and accuracy of path planning for fan inspection tasks in thermal power plants,this paper proposes an intelligent inspection robot path planning scheme based on an improved A^(*)algorithm.The...To improve the efficiency and accuracy of path planning for fan inspection tasks in thermal power plants,this paper proposes an intelligent inspection robot path planning scheme based on an improved A^(*)algorithm.The inspection robot utilizes multiple sensors to monitor key parameters of the fans,such as vibration,noise,and bearing temperature,and upload the data to the monitoring center.The robot’s inspection path employs the improved A^(*)algorithm,incorporating obstacle penalty terms,path reconstruction,and smoothing optimization techniques,thereby achieving optimal path planning for the inspection robot in complex environments.Simulation results demonstrate that the improved A^(*)algorithm significantly outperforms the traditional A^(*)algorithm in terms of total path distance,smoothness,and detour rate,effectively improving the execution efficiency of inspection tasks.展开更多
文摘Sewer pipe condition assessment by performing regular inspections is crucial for ensuring the systems’effective operation and maintenance.CCTV(closed-circuit television)is widely employed in North America to examine the internal conditions of sewage pipes.Due to the extensive inventory of pipes and associated costs,it is not practical for municipalities to conduct inspections on each sanitary sewage pipe section.According to the ASCE(American Society of Civil Engineers)infrastructure report published in 2021,combined investment needs for water and wastewater systems are estimated to be$150 billion during 2016-2025.Therefore,new solutions are needed to fill the trillion-dollar investment gap to improve the existing water and wastewater infrastructure for the coming years.ML(machine learning)based prediction model development is an effective method for predicting the condition of sewer pipes.In this research,sewer pipe inspection data from several municipalities are collected,which include variables such as pipe material,age,diameter,length,soil type,slope of construction,and PACP(Pipeline Assessment Certification Program)score.These sewer pipe data exhibit a severe imbalance in pipes’PACP scores,which is considered the target variable in the development of models.Due to this imbalanced dataset,the performance of the sewer prediction model is poor.This paper,therefore,aims to employ oversampling and hyperparameter tuning techniques to treat the imbalanced data and improve the model’s performance significantly.Utility owners and municipal asset managers can utilize the developed models to make more informed decisions on future inspections of sewer pipelines.
文摘The expected cost per unit of time for a sequential inspection policy is derived. It still has some difficulties to compute an optimal sequential policy numerically, which minimizes the expected cost of a system with finite number of inspections. This paper gives the algorithm for an optimal inspection schedule and specifies the computing procedure for a Weibull distribution. Using this algorithm, optimal inspection times are computed as a numerical result. Compared with the periodic point inspection, the policies in this paper reduce the cost successfully.
基金supported by the National Key Research and Development Program of China(grant number:2017YFC0806503)。
文摘With the increasing number of vehicles,manual security inspections are becoming more laborious at road checkpoints.To address it,a specialized Road Checkpoints Robot(RCRo)system is proposed,incorporated with enhanced You Only Look Once(YOLO)and a 6-degree-of-freedom(DOF)manipulator,for autonomous identity verification and vehicle inspection.The modified YOLO is characterized by large objects’sensitivity and faster detection speed,named“LF-YOLO”.The better sensitivity of large objects and the faster detection speed are achieved by means of the Dense module-based backbone network connecting two-scale detecting network,for object detection tasks,along with optimized anchor boxes and improved loss function.During the manipulator motion,Octree-aided motion control scheme is adopted for collision-free motion through Robot Operating System(ROS).The proposed LF-YOLO which utilizes continuous optimization strategy and residual technique provides a promising detector design,which has been found to be more effective during actual object detection,in terms of decreased average detection time by 68.25%and 60.60%,and increased average Intersection over Union(Io U)by 20.74%and6.79%compared to YOLOv3 and YOLOv4 through experiments.The comprehensive functional tests of RCRo system demonstrate the feasibility and competency of the multiple unmanned inspections in practice.
文摘This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).
基金National Natural Science Foundation of China(NSFC)(No.71231001)China Postdoctoral Science Foundation Funded Project(No.2013M530531)+1 种基金the Fundamental Research Funds for the Central Universities of China(Nos.FRF-M P-13-009A,FRF-TP-13-026A)the MOE PhD Supervisor Fund,China(No.20120006110025)
文摘Periodical inspections and an age-based preventive replacement( APR) model were proposed based on a two-stage failure process for a single component system. Inspection activities were performed at regular intervals. Once the system was identified to be at defective state by inspection,a maintenance decision needed to be made that whether to replace the defective system immediately or wait till the preset APR time. So a threshold was introduced into the model and called as inspection-based preventive replacement( IPR) threshold. If the distance from the defect identification point to the APR time was longer than the threshold, a preventive replacement( PR) action was made; otherwise PR action was to wait till the APR time. Two models were proposed and compared,and a numerical example was conducted to illustrate the applicability of the model.
基金supported by the National Natural Science Foundations of China (Nos. 51674031,51874022)。
文摘Visual inspection of the key components of nuclear power plants(NPPs)is important for NPP operation and maintenance. However,the underwater environment and existing radiation will lead to image degradation,thus making it difficult to identify surface defects. In this study,a method for improving the quality of underwater images is proposed.By analyzing the degradation characteristics of underwater detection image,the image enhancement technology is used to improve the color richness of the image,and then the improved dark channel prior(DCP)algorithm is used to restore it. By modifying the estimation formula of transmittance and background light,the correction of insufficient brightness in DCP restored image is realized. The proposed method is compared with other state-of-the-art methods. The results show that the proposed method can achieve higher scores and improve the image quality by correcting the color and restoring local details,thus effectively enhancing the reliability of visual inspection of NPPs.
文摘This paper covers the safely requirements and inspection methods for insulating components used in electrical accessories by an analyzing the properties of the insulating components used in electrical accessories based on the standard of IEC 60884.
文摘The manual visual inspections of façade building defects are posing a high and increasing cost for building asset managers,particularly when inspections delay projects or require asset outages,visits to decommissioned sites or work within hazardous environments.This paper reports on the development,testing and delivery of a working mobile app prototype to facilitate the inspections and documentation of building facade condition monitoring.The work presented builds upon the development of an online platform for remote building inspection based on the integration of methodologies and tools,including VR(virtual reality),and digital photogrammetry to collect real-time data that support automated decision making.The mobile app:(i)allows the user to import 3D models and 2D building plans;(ii)provides the means of first-person exploration of models via a VR headset;and(iii)captures,records and catalogues images of façade defect types,and the date and time.An inspection case study was used to demonstrate and evaluate the mobile app prototype.The Building Inspector app allows building professionals to manage inspections and to track past and ongoing monitoring of the condition of building façades.
基金a phased achievement of“Research on the Improvement of the Central Environmental Inspection System”(project No.21ZDA088)a key project on studying and interpreting the guiding principles of the Fifth Plenary Session of the 19th CPC Central Committeeunder the support of the National Social Science Fund of China。
文摘To develop China’s human rights cause with a people-centered approach,we should pay close attention to the concrete experiences of the general public regarding the protection of human rights.Deepening the research on the perception of respect for human rights can contribute to a more comprehensive understanding of the practical achievements of the hu man rights cause.Public environmental rights,as a new type of human rights,have become an important aspect of the development of the human rights cause in the new era.The central envi ronmental inspection,as an authoritative and interventionist vertical governance mechanism,promotes the implementation of environmental policies by local Party committees and govern ments and strengthens environmental information disclosure and public participation in environ mental matters.As a result,it contributes to the realization of public environmental rights and stimulates public perception of respect for human rights.Among them,the“look-back inspec tion is an important component of the central environmental inspection,and its implemen tation consolidates and enhances the previous inspection work.An empirical analysis based on the World Values Survey’s data for China indicates that residents in the provinces that have underg one“look-back inspections are more inclined to believe that human rights are adequately re spected compared to residents in the provinces that have not underwent such inspections.It suggests that the advancement and improvement of the central environmental inspection system promote improvements in ecological environment quality and contribute to enhancing the public percep tion of respect for human rights.
文摘Assume that a target is hidden or lost in one of several possible locations and is to be found by the unmanned aerial vehicle (UAV). A target can be either a hostile object or missing personnel in remote areas. Prior probabilities of target locations are known. Inspection operations done by the UAVs are imperfect, namely, probabilities of overlooking the hidden target and probabilities of false alarms exist for any possible location. The UAV has to sequentially inspect the locations so that to find the target with the minimum loss or damage incurred by the target before it is detected subject to a required level of confidence of target identification. A fast (polynomial-time) priority-based algorithm for finding an optimal search strategy is developed.
基金The research is supported by the National Natural Science Foundation of China(Grant Nos.7180116&72071138 and 72071071)the Young Talent Support Plan of Hebei Province.
文摘Bum-in has been proven effective in identifying and removing defective products before they are delivered to customers.Most existing bum-in models adopt a one-shot scheme,which may not be sufficient enough for identification.Borrowing the idea from sequential inspections for remaining useful life prediction and accelerated lifetime test,this study proposes a sequential degradation-based bum-in model with multiple periodic inspections.At each inspection epoch,the posterior probability that a product belongs to a normal one is updated with the inspected degradation level.Based on the degradation level and the updated posterior probability,a product can be disposed,put into field use,or kept in the test till the next inspection epoch.We cast the problem into a partially observed Markov decision process to minimize the expected total bum-in cost of a product,and derive some interesting structures of the optimal policy.Then,algorithms are provided to find the joint optimal inspection period and number of inspections in steps.A numerical study is also provided to illustrate the effectiveness of our proposed model.
基金supported by the National Key Research and Development Program of China(No.2024YFB3212901)National Natural Science Foundation of China(12072189)the Medicine and Engineering Interdisciplinary Research Fund of Shanghai Jiao Tong University(No.YG2025ZD05)。
文摘Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.
文摘Ⅰ. INTRODUCTION The nondestructive inspection using Compton scattering has many advantages, such as direct displays fast throughput, and easy computer control. Being a supplement to currently available nondestructive inspection methods, it has a specific application in industry. This inspection technique has attracted special attention at home and abroad, therefore, the experimental technology is in rapid progress in recent years. For example, the
基金Supported by Nanjing University of Aeronautics and Astronautics Innovation Team FundChinese Medical Association-L'Oreal Chinese Healthy Skin/Hair Research Project(S10)
文摘Objective：To study the differences in a special region（SR） corresponding to five internal organs between the young and the elderly and to verify the effectiveness of a developed system for objectifying research in colour inspections of Chinese medicine（CICM）.Methods：An image acquisition device imitating daylight to meet the requirement of CICM was designed.Image processing software based on CICM theory was developed.A total of 83 normal people were sampled and assigned to two groups.The first group（Group I）included 30 people with an average age of 24 ±2,and the second group（Group Ⅱ） included 53 people with an average age of 74 ±4.After image processing,the chromaticity of 10 SRs corresponding to five internal organs was calculated.R,G,and B represent the chromaticity of color red,green,and blue,L indicates color brightness,whereas a and b denote red and yellow respectively.The difference between the young and the elderly was analyzed.Results：（1） The chromaticity of each SR corresponding to five organs was obtained.The average R,G,B,L,a,and b of the sample were 194.4,147.6,119.3,65.2,15.5,and 22.3,respectively.（2） The R,G,B,and L of the young were greater than those of the elderly,but the a and b of the young were less than those of the elderly.（3） A statistically significant difference in each SR was found between the young and the elderly（P0.05）.The total differences for the Lung（Fei）,Heart（Xin）,Liver（Gan）,Spleen（Pi）,and Kidney（Shen） were 50%（3/6）,66.7%（4/6）,66.7%（4/6）,83.3%（5/6）,and 91.7%（33/36）,respectively.However,the Kidney SR had the greatest statistical discrepancy.Conclusion：The old Chinese saying that human Kidney deficiency worsens with age was verified by the results.The objectifying system used to examine CICM was effective.Thus,this system may be used as a basis for further research.
文摘Dr.Leon van Paassen has been selected as the winner for the Distinguished 2025 Biogeotechnics Lecture Award.Leon van Paassen is an expert on biogeotechnics with more than 20 years of experience in academia and industry.He graduated as an Engineering Geologist at Delft University of Technology in 2002.After graduation,he performed foundation inspections and vibration monitoring at IFCO foundations and worked as a consultant and researcher at GeoDelft which later became Deltares.
文摘Based on inspection data,the authors analyze and summarize the main types and distribution characteristics of tunnel structural defects.These defects are classified into three types:surface defects,internal defects,and defects behind the structure.To address the need for rapid detection of different defect types,the current state of rapid detection technologies and equipment,both domestically and internationally,is systematically reviewed.The research reveals that surface defect detection technologies and equipment have developed rapidly in recent years.Notably,the integration of machine vision and laser scanning technologies have significantly improved detection efficiency and accuracy,achieving crack detection precision of up to 0.1 mm.However,the non-contact rapid detection of internal and behind-the-structure defects remains constrained by hardware limitations,with traditional detection remaining dominant.Nevertheless,phased array radar,ultrasonic,and acoustic vibration detection technologies have become research hotspots in recent years,offering promising directions for detecting these challenging defect types.Additionally,the application of multisensor fusion technology in rapid detection equipment has further enhanced detection capabilities.Devices such as cameras,3D laser scanners,infrared thermal imagers,and radar demonstrate significant advantages in rapid detection.Future research in tunnel inspection should prioritize breakthroughs in rapid detection technologies for internal and behind-the-structure defects.Efforts should also focus on developing multifunctional integrated detection vehicles that can simultaneously inspect both surface and internal structures.Furthermore,progress in fully automated,intelligent systems with precise defect identification and real-time reporting will be essential to significantly improve the efficiency and accuracy of tunnel inspection.
基金funded by National Natural Science Foundation of China(Grant Nos.52130504,52305577,and 52175509)the Key Research and Development Plan of Hubei Province(Grant No.2022BAA013)+4 种基金the Major Program(JD)of Hubei Province(Grant No.2023BAA008-2)the Interdisciplinary Research Program of Huazhong University of Science and Technology(2023JCYJ047)the Innovation Project of Optics Valley Laboratory(Grant No.OVL2023PY003)the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(Grant No.GZB20230244)the fellowship from the China Postdoctoral Science Foundation(2024M750995)。
文摘In integrated circuit(IC)manufacturing,fast,nondestructive,and precise detection of defects in patterned wafers,realized by bright-field microscopy,is one of the critical factors for ensuring the final performance and yields of chips.With the critical dimensions of IC nanostructures continuing to shrink,directly imaging or classifying deep-subwavelength defects by bright-field microscopy is challenging due to the well-known diffraction barrier,the weak scattering effect,and the faint correlation between the scattering cross-section and the defect morphology.Herein,we propose an optical far-field inspection method based on the form-birefringence scattering imaging of the defective nanostructure,which can identify and classify various defects without requiring optical super-resolution.The technique is built upon the principle of breaking the optical form birefringence of the original periodic nanostructures by the defect perturbation under the anisotropic illumination modes,such as the orthogonally polarized plane waves,then combined with the high-order difference of far-field images.We validated the feasibility and effectiveness of the proposed method in detecting deep subwavelength defects through rigid vector imaging modeling and optical detection experiments of various defective nanostructures based on polarization microscopy.On this basis,an intelligent classification algorithm for typical patterned defects based on a dual-channel AlexNet neural network has been proposed,stabilizing the classification accuracy ofλ/16-sized defects with highly similar features at more than 90%.The strong classification capability of the two-channel network on typical patterned defects can be attributed to the high-order difference image and its transverse gradient being used as the network’s input,which highlights the polarization modulation difference between different patterned defects more significantly than conventional bright-field microscopy results.This work will provide a new but easy-to-operate method for detecting and classifying deep-subwavelength defects in patterned wafers or photomasks,which thus endows current online inspection equipment with more missions in advanced IC manufacturing.
文摘To improve the efficiency and accuracy of path planning for fan inspection tasks in thermal power plants,this paper proposes an intelligent inspection robot path planning scheme based on an improved A^(*)algorithm.The inspection robot utilizes multiple sensors to monitor key parameters of the fans,such as vibration,noise,and bearing temperature,and upload the data to the monitoring center.The robot’s inspection path employs the improved A^(*)algorithm,incorporating obstacle penalty terms,path reconstruction,and smoothing optimization techniques,thereby achieving optimal path planning for the inspection robot in complex environments.Simulation results demonstrate that the improved A^(*)algorithm significantly outperforms the traditional A^(*)algorithm in terms of total path distance,smoothness,and detour rate,effectively improving the execution efficiency of inspection tasks.
