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The Impact and Response of Automatic Driving Technology Standards on the Determination of Criminal Responsibility for Traffic Accidents in China
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作者 Sun Jianfeng 《科技与法律(中英文)》 2026年第1期134-148,共15页
With the continuous progress of automatic driving technology,automatic driving technology standards are gradually affecting the determination of criminal responsibility for traffic accidents in China.At present,the ch... With the continuous progress of automatic driving technology,automatic driving technology standards are gradually affecting the determination of criminal responsibility for traffic accidents in China.At present,the characteristics and tendency of China's automatic driving technology standards present the situation of high policy relevance coexisting with low normative binding,professionalism coexist with barriers,forefront coexist with ambiguity.Therefore,challenges are presented both theoretically and practically on the determination of criminal responsibility based on automatic driving technology standard..In this regard,the misunderstanding should be clarified in theory:The legal order under the automatic driving technology standard has constitutionality and systematic,and there is a balance between the frontier of automatic driving technology development and the lagging of criminal law.The automatic driving technology risk level system should be built to clarify the boundary of the effectiveness of criminal law norms,seeking fora breakthrough in the application of the establishment of a comprehensive judgment system of the risks and accidents and the system of evidence to prove the system,which clarifies the determination of criminal responsibility under the automatic driving technology standard.This essay hopes to pursue breakthroughs in the application-to establish a comprehensive judgment system of risks and accidents as well as an evidence proof system,so as to clarify the determination of criminal responsibility under automatic driving technology standards. 展开更多
关键词 automatic driving traffic accidents criminal responsibility legal order
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Community assembly and nitrogen metabolic characteristics of size-fractionated microorganisms in floating bed restoration area
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作者 Yi SHI Rui ZHAO +1 位作者 Lingfeng HUANG Wenjing ZHANG 《Journal of Oceanology and Limnology》 2026年第1期184-200,共17页
Ecological floating bed is an important biological remediation method for water pollution control.During the removal of excess nutrients and pollutants,changes in environmental factors affect the characteristics of mi... Ecological floating bed is an important biological remediation method for water pollution control.During the removal of excess nutrients and pollutants,changes in environmental factors affect the characteristics of microorganisms in aquatic ecosystems.To understand the influences of ecological floating beds on size-fractionated microorganisms,we investigated the community assembly and nitrogen metabolic characteristics of three size-fractionated microorganism groups in the ecological floating bed area,using 18S rDNA,16S rDNA metabarcoding,and metagenomic sequencing techniques.Firstly,we discovered substantial differences between size-fractionated groups in the diversity and compositions of both microeukaryotic and bacterial communities,as well as the influences of floating beds on specific groups.The floating beds appeared to provide more habitats for heterotrophs and symbiotes while potentially inhibiting the growth of certain phytoplankton(cyanobacteria).Secondly,we observed that microeukaryotic and bacterial communities were predominantly influenced by stochastic and deterministic processes,respectively,and they both exhibited distinct patterns across different size-fractionated groups.Notably,microeukaryotic community assembly demonstrated a greater sensitivity to ecological floating beds,as indicated by an increase in dispersal limitation processes.Finally,the nitrogen metabolism functional genes revealed that microbes associated with large-sized particles played a crucial role in dissimilatory nitrate reduction to ammonium(DNRA)and denitrification processes within the floating bed area,thereby facilitating the removal of excess nitrogen nutrients from the water.In contrast,freeliving microorganisms from small-sized groups were linked mainly to the genes involved in nitrogen assimilation and assimilatory nitrate reduction to ammonium(ANRA)processes.These findings help understand the impact of ecological floating beds on the diversity and functional characteristics of microorganism communities in different size-fractionated groups. 展开更多
关键词 size-fractionated MICROORGANISM METAGENOMIC nitrogen metabolism assembly process ecological floating bed
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SW-Segment:Automatic segmentation of shock waves in schlieren images based on image correlation and graph search
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作者 Qinglong YIN Yuan TIAN +6 位作者 Yizhu WANG Liang CHEN Feng XING Liwei SU Yue ZHANG Huijun TAN Depeng WANG 《Science China(Technological Sciences)》 2026年第2期44-54,共11页
Schlieren imaging is a widely used technique to visualize the structure of supersonic flow field,which is usually dominated by shock waves.Precise identification of shock waves in schlieren image provides critical ins... Schlieren imaging is a widely used technique to visualize the structure of supersonic flow field,which is usually dominated by shock waves.Precise identification of shock waves in schlieren image provides critical insights for flow diagnostics,especially for supersonic inlet whose performance is highly associated with that of the whole flight.However,conventional shock wave identification methods have limited accuracy in segmenting the shock wave.To overcome the limitation,we proposed an automated shock wave identification method(SW-Segment)that can attain high resolution and automatic shock wave segmentation by integrating correlation-based feature extraction with graph search.We demonstrated the efficacy of SW-Segment via the identification of shock waves in simulatively and experimentally obtained schlieren image.The results proved that SW-Segment showed a shock wave identification accuracy of 95.24%in the numerical schlieren image and an accuracy of 88.33%in the experimental image,clearly demonstrating its reliability.SW-Segment holds broad applicability for shock wave detection in diverse schlieren imaging scenarios,offering robust data support for flow field analysis and supersonic flight design. 展开更多
关键词 schlieren image shock wave identification image correlation graph search automatic segmentation
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Gradient-Guided Assembly Instruction Relocation for Adversarial Attacks Against Binary Code Similarity Detection
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作者 Ran Wei Hui Shu 《Computers, Materials & Continua》 2026年第1期1372-1394,共23页
Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Althoug... Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Although adversarial examples can strategically undermine the accuracy of BCSD models and protect critical code,existing techniques predominantly depend on inserting artificial instructions,which incur high computational costs and offer limited diversity of perturbations.To address these limitations,we propose AIMA,a novel gradient-guided assembly instruction relocation method.Our method decouples the detection model into tokenization,embedding,and encoding layers to enable efficient gradient computation.Since token IDs of instructions are discrete and nondifferentiable,we compute gradients in the continuous embedding space to evaluate the influence of each token.The most critical tokens are identified by calculating the L2 norm of their embedding gradients.We then establish a mapping between instructions and their corresponding tokens to aggregate token-level importance into instructionlevel significance.To maximize adversarial impact,a sliding window algorithm selects the most influential contiguous segments for relocation,ensuring optimal perturbation with minimal length.This approach efficiently locates critical code regions without expensive search operations.The selected segments are relocated outside their original function boundaries via a jump mechanism,which preserves runtime control flow and functionality while introducing“deletion”effects in the static instruction sequence.Extensive experiments show that AIMA reduces similarity scores by up to 35.8%in state-of-the-art BCSD models.When incorporated into training data,it also enhances model robustness,achieving a 5.9%improvement in AUROC. 展开更多
关键词 assembly instruction relocation adversary attack binary code similarity detection
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Effects of host niche and genotype on the diversity and community assembly of the fungal community in peas(Pisum sativum L.)
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作者 Yu Wang Linying Xu +7 位作者 Liquan Zhang Rui Zhang Qiong Liu Hongquan Liu Tao Yang Haoqing Zhang Tida Ge Li Wang 《Journal of Integrative Agriculture》 2026年第2期529-539,共11页
Fungi play crucial roles in nutrient acquisition,plant growth promotion,and the enhancement of resistance to both abiotic and biotic stresses.However,studies on the fungal communities associated with peas (Pisum sativ... Fungi play crucial roles in nutrient acquisition,plant growth promotion,and the enhancement of resistance to both abiotic and biotic stresses.However,studies on the fungal communities associated with peas (Pisum sativum L.) remain limited.In this study,we systematically investigated the ecological effects of host niches (soil,root,stem,leaf,and pod) and genotypes on the diversity and composition of fungal communities in peas using a multi-level approach that encompassed pattern recognition (β-diversity decomposition),mechanism validation (neutral community model testing),and dynamic tracking methods (migration pathway source-tracking).The results revealed that the dominant fungal phyla across niches and genotypes were Ascomycota,Basidiomycota,and Mortierellomycota,and the community structures of the soil–plant continuum were primarily determined by the pea niches rather than genotypes.β-diversity decomposition was largely attributed to species replacement rather than richness differences,indicating strong niche specificity and microbial replacement across microhabitats.Neutral model analysis revealed that stochastic processes influenced genotypeassociated communities,while deterministic processes played a dominant role in niche-based community assembly.Source-tracking analysis identified niche-to-niche fungal migration,with Erysiphe,Fusarium,Cephaliophora,Ascobolus,Alternaria,and Aspergillus as the key genera.Migration rates from exogenous to endogenous niches were low (1.3–61.5%),whereas those within exogenous (64.4–83.7%) or endogenous (73.9–96.4%) compartments were much higher,suggesting that the pea epidermis acts as a selective barrier that filters and enriches microbial communities prior to internal colonization.This study provides comprehensive insights into the mechanisms of host filtering,enrichment and microbial sourcing,which increases our understanding of the assembly rules of the pea-associated fungal microbiome. 展开更多
关键词 β-diversity decomposition fungal community assembly PEA source-sink relationships host niche GENOTYPE
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A Q-Learning Improved Particle Swarm Optimization for Aircraft Pulsating Assembly Line Scheduling Problem Considering Skilled Operator Allocation
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作者 Xiaoyu Wen Haohao Liu +6 位作者 Xinyu Zhang Haoqi Wang Yuyan Zhang Guoyong Ye Hongwen Xing Siren Liu Hao Li 《Computers, Materials & Continua》 2026年第1期1503-1529,共27页
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper... Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines. 展开更多
关键词 Aircraft pulsating assembly lines skilled operator reinforcement learning PSO reverse scheduling
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Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
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作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
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Recent progress on nanoadjuvants:From design and assembly to biomedical imaging
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作者 Fan Meng Yiqing Zhang +3 位作者 Zhen Yuan Zhangyong Hong Bin Yang Jian Zhang 《Chinese Chemical Letters》 2026年第2期126-134,共9页
Adjuvants enhance and prolong the immune response to therapeutic agents,such as drugs and vaccines.However,conventional adjuvants have limitations in terms of immune specificity and duration.Nanoadjuvants can leverage... Adjuvants enhance and prolong the immune response to therapeutic agents,such as drugs and vaccines.However,conventional adjuvants have limitations in terms of immune specificity and duration.Nanoadjuvants can leverage their nanoscale size to increase the capture efficacy of antigens by antigen-presenting cells and improve immunogen presentation for targeted delivery.Furthermore,noninvasive visualization of bifunctional nanoadjuvants with integrated efficacy and imaging postdelivery can provide insights into in vivo distribution and performance,aiding in the optimization and design of new dosage forms.This review systematically summarizes the structure,assembly,and function of nanoadjuvants alongside contrast agents.It delves into the impact of complex structures formed by nanoadjuvant-contrast agent interactions on antigen presentation,migration,imaging tracking,and visualization of immune cell recruitment.It also discusses how imaging can determine optimal immune intervals,vaccine safety,and toxicity while enabling diagnostic and therapeutic integration.Moreover,this paper discusses potential applications of novel adjuvants and promising imaging technologies that could have implications for future vaccine and drug development endeavors. 展开更多
关键词 Nanoadjuvant Contrast agent Structure and assembly Integration of diagnosis and treatment Biomedical imaging
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Deep Learning-Based Toolkit Inspection:Object Detection and Segmentation in Assembly Lines
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作者 Arvind Mukundan Riya Karmakar +1 位作者 Devansh Gupta Hsiang-Chen Wang 《Computers, Materials & Continua》 2026年第1期1255-1277,共23页
Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone t... Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone to errors and lacks consistency,emphasizing the need for a reliable and automated inspection system.Leveraging both object detection and image segmentation approaches,this research proposes a vision-based solution for the detection of various kinds of tools in the toolkit using deep learning(DL)models.Two Intel RealSense D455f depth cameras were arranged in a top down configuration to capture both RGB and depth images of the toolkits.After applying multiple constraints and enhancing them through preprocessing and augmentation,a dataset consisting of 3300 annotated RGB-D photos was generated.Several DL models were selected through a comprehensive assessment of mean Average Precision(mAP),precision-recall equilibrium,inference latency(target≥30 FPS),and computational burden,resulting in a preference for YOLO and Region-based Convolutional Neural Networks(R-CNN)variants over ViT-based models due to the latter’s increased latency and resource requirements.YOLOV5,YOLOV8,YOLOV11,Faster R-CNN,and Mask R-CNN were trained on the annotated dataset and evaluated using key performance metrics(Recall,Accuracy,F1-score,and Precision).YOLOV11 demonstrated balanced excellence with 93.0%precision,89.9%recall,and a 90.6%F1-score in object detection,as well as 96.9%precision,95.3%recall,and a 96.5%F1-score in instance segmentation with an average inference time of 25 ms per frame(≈40 FPS),demonstrating real-time performance.Leveraging these results,a YOLOV11-based windows application was successfully deployed in a real-time assembly line environment,where it accurately processed live video streams to detect and segment tools within toolkits,demonstrating its practical effectiveness in industrial automation.The application is capable of precisely measuring socket dimensions by utilising edge detection techniques on YOLOv11 segmentation masks,in addition to detection and segmentation.This makes it possible to do specification-level quality control right on the assembly line,which improves the ability to examine things in real time.The implementation is a big step forward for intelligent manufacturing in the Industry 4.0 paradigm.It provides a scalable,efficient,and accurate way to do automated inspection and dimensional verification activities. 展开更多
关键词 Tool detection image segmentation object detection assembly line automation Industry 4.0 Intel RealSense deep learning toolkit verification RGB-D imaging quality assurance
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Telomere-to-telomere genome assembly reveals the genomic architecture of disease resistance and yield coordination in elite wheat YM33
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作者 Guofeng Lv Yating Wang +15 位作者 Heping Zhang Yuning Shen Wenjing Hu Datong Liu Mengmeng Liu Wenna Wang Yuwen Gao Caixia Lan Tongde Bie Hongya Wu Wei Chen Yong Zhang Jianwei Zhang Chao He Wenhao Yan Derong Gao 《Molecular Plant》 2026年第2期213-216,共4页
Wheat(Triticum aestivum)faces significant threats from diseases such as powdery mildew(Blumeria graminis)and Fusarium head blight(FHB;caused by Fusarium graminearum),which cause severe yield losses.Moreover,the antago... Wheat(Triticum aestivum)faces significant threats from diseases such as powdery mildew(Blumeria graminis)and Fusarium head blight(FHB;caused by Fusarium graminearum),which cause severe yield losses.Moreover,the antagonism between yield-related traits and disease resistance makes yield resistance coordination a major challenge in wheat breeding.The lack of genetic resources combining both disease resistance and high yield constrains the elucidation of underlying resistance-yield trade-off mechanisms,thereby hindering the development of high-yield and disease-resistant wheat cultivars.Remarkably,Yangmai 33(YM33),a notable wheat cultivar with resistance to both powdery mildew and FHB as well as high-yield performance,was recently developed.It offers a unique opportunity to dissect the genomic architecture underlying the coordination between disease resistance and yield. 展开更多
关键词 fusarium head blight fhbcaused powdery mildew blumeria yield resistance coordination telomere telomere genome assembly disease resistance elite wheat genetic resources genomic architecture
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Analysis of Effective Working Hours of Automatic Assembly Equipment for Aircraft Assembly Stations 被引量:1
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作者 ZHOU Xianxin XIN Bo +1 位作者 GONG Yadong LI Chen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第6期903-913,共11页
To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dyna... To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dynamic mixed Weibull distribution(DMWD)model.Firstly,according to the features of aircraft assembling,a DMWD model considering the dynamic reliability of multiple subsystems and their synthetic effects on the whole equipment is established.A typical automatic drilling&riveting machine is selected as the research object,and the dynamic weights of reliability of three subsystems are modeled and solved.Subsequently the unknown parameters of the DMWD model are estimated based on maximum likelihood estimation(MLE)and Newton-Raphson method.Finally,the EWH of an automatic station is defined and modeled by using the solved dynamic reliability function.Based on the experimental study on a real automatic drilling&riveting machine from a wing panel assembly station,it is shown that the proposed DMWD and EWH models could effectively calculate the equipment reliability with full consideration of its multiple subsystems.The DMWD model is more suitable for improving the solution precision of EWH than the traditional three-parameter Weibull distribution. 展开更多
关键词 automatic assembly equipment effective working hours(EWH) Weibull distribution RELIABILITY
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Automatic generation of assembly dimension chain based on tolerance cell 被引量:2
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作者 Zhu Xinglei Li lqngguang +1 位作者 Wang Wei Liu Hao 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期77-83,共7页
In the process of generating assembly dimension chain automatically, there are many problems such as complex assembly relationship, variety of constraints of components and complex dimension and tolerance relations of... In the process of generating assembly dimension chain automatically, there are many problems such as complex assembly relationship, variety of constraints of components and complex dimension and tolerance relations of components. These problems lead to many difficulties in search process and need lots of man-machine interaction. Because of these difficulties, this paper presents a method of automatic generation of assembly dimension chain based on tolerance cell. This method is realized through obtaining assembly tolerance cell and part tolerance cell first. These two types of tolerance cell are extracted and expressed in the form of linked list structure in computer further. Then assembly dimension chain is searched automatically based on obtained tolerance cell, and the correct assembly dimension chain is extracted finally. A system of generating assembly dimension chain automatically has been developed based on DELMIA and successfully deployed in aircraft assembly simulation in the engineerine practice. 展开更多
关键词 tolerance cell assembly information model assembly dimension chain
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A Laser Line Scanner Based Hole Position Correction Mechanism for Automatic Drilling and Riveting in Aircraft Assembly
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作者 ZHANG Lin TIAN Wei +3 位作者 SUN Hailong XUE Qiwei LIU Yangyang LIAO Wenhe 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第6期952-963,共12页
The low-stiffness of aircraft skins may results in the differences between aircraft actual parts and their theoretical models,which will consequently affect the accuracy of automatic drilling and riveting in aircraft ... The low-stiffness of aircraft skins may results in the differences between aircraft actual parts and their theoretical models,which will consequently affect the accuracy of automatic drilling and riveting in aircraft assembly.In this paper,a novel approach of hole position correction using laser line scanner(LLS)is proposed to assign a single row of holes on the parts’surfaces.First,we adopt a space circle fitting method and the random sample consensus(RANSAC)to obtain the precise coordinates of center of the datum holes’coordinates.Second,LLS is calibrated by the laser tracker,and the relations between the LLS coordinate system and the tool coordinate system(TCS)can be calculated.Third,the kinematics model of the automatic riveting machine is established based on a two-point referencing strategy proposed in this paper.Thus,the positions of the holes to be drilled can be adjusted.Finally,the experimental results show that in TCS the measurement error of LLS is less than 0.1 mm,and the correction error of the hole position is less than 0.5 mm,which demonstrates the reliability of our method. 展开更多
关键词 aircraft assembly automatic drilling and riveting system(ADRS) laser line scanner(LLS) position correction
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Method of Measuring Fixture Automatic Design and Assembly for Auto-Body Part
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作者 胡彩旗 林忠钦 来新民 《Journal of Beijing Institute of Technology》 EI CAS 2005年第3期349-352,共4页
A method of 3-D measuring fixture automatic assembly for auto-body part is presented. Locating constraint mapping technique and assembly rule-based reasoning are applied. Calculating algorithm of the position and pose... A method of 3-D measuring fixture automatic assembly for auto-body part is presented. Locating constraint mapping technique and assembly rule-based reasoning are applied. Calculating algorithm of the position and pose for the part model, fixture configuration and fixture elements in virtual auto-body assembly space are given. Transforming fixture element from itself coordinate system space to assembly space with homogeneous transformation matrix is realized. Based on the second development technique of unigraphics(UG), the automated assembly is implemented with application program interface (API) function. Lastly the automated assembly of measuring fixture for rear longeron as a case is implemented. 展开更多
关键词 auto-body part measuring fixture automated assembly
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Automatic Modification of Local Drilling Holes via Double Pre-Assembly Holes
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作者 Qiubai Yan Wenliang Chen 《World Journal of Engineering and Technology》 2015年第3期191-196,共6页
Manufacturing accuracy, especially position accuracy of fastener holes, directly affects service life and security of aircraft. The traditional modification has poor robustness, while the modification based on laser t... Manufacturing accuracy, especially position accuracy of fastener holes, directly affects service life and security of aircraft. The traditional modification has poor robustness, while the modification based on laser tracker costs too much. To improve the relative position accuracy of aircraft assembly drilling, and ensure the hole-edge distance requirement, a method was presented to modify the coordinates of drilling holes. Based on online inspecting two positions of pre-assembly holes and their theoretical coordinates, the spatial coordinate transformation matrix of modification could be calculated. Thus the straight drilling holes could be modified. The method improves relative position accuracy of drilling on simple structure effectively. And it reduces the requirement of absolute position accuracy and the cost of position modification. And the process technician also can use this method to decide the position accuracy of different pre-assembly holes based on the accuracy requirement of assembly holes. 展开更多
关键词 POSITION Accuracy HOLES POSITION MODIFICATION automatic DRILLING PRE-assembly HOLES Online Inspecting
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Design and development of automatic systems for assembly welding muffler of Santana automobile
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作者 HE Defu YU hailiang +1 位作者 TANG Xinhua WANG Sizuo and ZhUANG yongming(Welding Depaytment. Shanghai Jiaotong University, Shanghai, 200030.) 《China Welding》 EI CAS 1996年第1期49-58,共10页
Two types of automatic systems.for assembly welding. Santana automobile muffler in mass production are suggested in this paper Such systems were aPPlied to manufacture at the beginning of 1995, and were approved to ha... Two types of automatic systems.for assembly welding. Santana automobile muffler in mass production are suggested in this paper Such systems were aPPlied to manufacture at the beginning of 1995, and were approved to have high productivity and quality but low cost. It is an optimal selection for someone who manufacture automobile muffler or Similar productlons. 展开更多
关键词 assembly of mumer welding automation GMAW. PC control
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Application of PFMEA for Identification of Self-Recovering Failures in Production Lines for Automatic Assembly of Capacitors
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作者 Todor Neshkov Aleksandar Stefanov Vladislav Ivanov 《Journal of Mechanics Engineering and Automation》 2013年第3期173-178,共6页
Quality control is an important part of the capacitors automatic assembly process. Traditionally this control is being realized through a series of electrical measurements including capacity, tension, and tgct. In mos... Quality control is an important part of the capacitors automatic assembly process. Traditionally this control is being realized through a series of electrical measurements including capacity, tension, and tgct. In most cases, these measurements are not suitable for detecting defects that appear as a result of failures of certain elements of the assembly lines. These so called self-recovering failures very often remain unnoticed, because they do not cause a suspension of the assembly process and if not taken into consideration, they can seriously menace the final product quality. In this paper, the authors use PFMEA to identify and evaluate the risk of the self-recovering failures. They also propose a simple Simulink model, which could be useful when trying to estimate the effect of installing new control devices at an existing assembly line upon its overall reliability and productivity. 展开更多
关键词 FAILURE EFFECT assembly line SIMULATION
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AUTOMATIC PLANNING OF ASSEMBLING ORDER FROM ASSEMBLY DRAWING
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作者 Li Shinan Jing Haidong 《Computer Aided Drafting,Design and Manufacturing》 1997年第1期73-78,共0页
It is important to plan the assembling order automatically in order to reach assembling mechanization, especially intellectualization. The foundation of assembling order is how to understanding assembly drawing automa... It is important to plan the assembling order automatically in order to reach assembling mechanization, especially intellectualization. The foundation of assembling order is how to understanding assembly drawing automatically, namely the capacity of machine “drawing reading”. This paper introduces the general structure of ESUAD(Expert System of Understanding Assembly Drawing) system, its knowledge representation, the automatical understanding of assembly drawing, the plan of assembling order. Finally the paper will give the experiment result. 展开更多
关键词 ES assembly drawing assembling order
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Automated Sequencing and Subassembly Detection in Automobile Body Assembly Planning 被引量:3
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作者 ZHANG Yi-zhu 1, NI Jun 2, LIN Zhong-qin 1, LAI Xin-min 1 (1. Institute of Mechanics and Engineering, Shanghai Jiaotong Universit y, Shanghai 200030, China 2. Department of Mechanical Engineering, The University of Michigan, Michigan, U SA) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期145-,共1页
The choice of the sequence in which parts or subass em blies are put together in the mechanical assembly of a product can drastical ly affect the efficiency of the assembly process. Unlike metal cutting operation s wh... The choice of the sequence in which parts or subass em blies are put together in the mechanical assembly of a product can drastical ly affect the efficiency of the assembly process. Unlike metal cutting operation s where computer aided system have been available for some 15 to 25 years to hel p manufacturing engineers in generating cutting sequences and NC programs, the m ajority of assembly planning tasks in automobile body design is still manually p erformed by assembly designers according to their past experiences. This has prolonged the production lead time and time to market. This paper describes a p rocedure to automatically derive all the feasible assembly sequences for automob ile body assembly. The procedure is based on a mathematical model of the automob ile body, obtained through the definitions of the connection matrix and contract ed matrix. These two matrices represent the precedence constraint knowledge amon g components and subassemblies. The possible subassemblies are automatically det ected by satisfying some mathematical conditions applicable to these matrices. F or each subassembly and the whole product, all the possible assembly sequences a re generated by rearranging the initial connection sub-matrix and the contracte d matrix. The procedure is applicable to compliant component assemblies, suc h as the automobile body assembly, aircraft frame assembly, and can solve the "combinatorial explosion" problem efficiently. 展开更多
关键词 assemblIES PLANNING subassemblies
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Clinical observation on prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation 被引量:3
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作者 Yan-Mei Huang Dong Ouyang 《World Journal of Gastrointestinal Surgery》 2025年第1期209-216,共8页
BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different tre... BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good. 展开更多
关键词 Mixed hemorrhoids Polidocanol injection automatic elastic thread ligation operation Postoperative hemorrhage The degree of pain Recurrent rate
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