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Automaticity Theory and Its Implications for ELT in China
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作者 李斌 《海外英语》 2012年第13期136-138,共3页
The paper presents an overview of automaticity research,particularly the influential theories concerned.It highlights four automatic learning models:rule-based approach,item/instance-based approach,exemplar-based rand... The paper presents an overview of automaticity research,particularly the influential theories concerned.It highlights four automatic learning models:rule-based approach,item/instance-based approach,exemplar-based random walk model,and restructuring model.Model 1 underlines that automatic processing is proceduralization of declarative knowledge with repeated practice being the prerequisite;model 2 stresses that automaticity is the direct memory retrieval and instance amount together with quality affects retrieval speed;model 3 emphasizes that memory retrieval is similarity-based,and responses are determined by the relative similarity of exemplars;the last argues that it is restructuring other than simply practice that increases the possibility of automaticity.Finally,respective implications of the learning models for ELT(English language teaching) in China are discussed. 展开更多
关键词 automaticity RESTRUCTURING ENGLISH TEACHING
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The automaticity of Mahaim fibre and its response to effective ablation
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作者 麻付胜 马坚 +4 位作者 楚建民 方丕华 王方正 陈新 张澍 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第12期1768-1771,共4页
Background Typical accessory pathways (APs) of Wolf Parkinson White syndrome have been widely discussed in recent decades However, the characteristics of the special AP, Mahaim fibre, are not so clear It is known that... Background Typical accessory pathways (APs) of Wolf Parkinson White syndrome have been widely discussed in recent decades However, the characteristics of the special AP, Mahaim fibre, are not so clear It is known that these fibres have antegrade conduction only, long conduction time, decremental node like conduction and automaticity properties This study was to elucidate the automaticity of Mahaim fibre and its response to effective ablation Methods Thirteen patients with Mahaim fibre (ten atrioventricular and three atriofascicular accessory pathways) were subjected to electrophysiological study and radiofrequency ablation via catheter The incidence and characteristics of anautomatic rhythm originating from Mahaim fibre were observed during the whole procedure, especially during radiofrequency current delivery Results Repetitive and short run automatic rhythm (rate: 65-72 beats per minute), with a QRS morphology similar to that of clinical pre excited atrioventricular re entrant tachycardia (AVRT), occurred in two patients during sinus rhythm Conduction via Mahaim fibre was successfully eliminated by radiofrequency current Fourteen applications of RF were associated with irregularly accelerated automatic tachycardia of Mahaim fibre (with a sensitivity of 78%), lasting for 1 2-14 seconds However, such automatic tachycardia of Mahaim fibre did not occur during 54 failed applications of radiofrequency current Conclusions Mahaim fibre has the function of automaticity The accelerated automatic tachycardia of Mahaim fibre occur red during radiofrequency catheter ablation can be used as a predictor for successful procedure 展开更多
关键词 Mahaim fibre automaticity radiofrequency catheter ablation
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Automatic for the People AI is reshaping diagnosis,but who is responsible when it goes wrong?
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作者 Wang Zhe 《China Report ASEAN》 2026年第2期55-57,共3页
At Beijing Tongren Hospital,an AI-powered retinal screening system can screen for 10 chronic illnesses from just two photos in two minutes.Using one fundus image from each eye,it scans for early signs of diabetic reti... At Beijing Tongren Hospital,an AI-powered retinal screening system can screen for 10 chronic illnesses from just two photos in two minutes.Using one fundus image from each eye,it scans for early signs of diabetic retinopathy,hypertension,atherosclerosis and other conditions,with a reported accuracy of about 90 percent. 展开更多
关键词 diabetic retinopathyhypertensionatherosclerosis responsibility chronic illnesses accuracy AI screen chronic illnesses AUTOMATIC retinal screening
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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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Research on the reliability of motion accuracy for ammunition conveyor in artillery automatic loading system
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作者 Guangsong Chen Junhua Chen +1 位作者 Jinsong Tang Yongji Liu 《Chinese Journal of Mechanical Engineering》 2026年第1期102-114,共13页
The automatic loading systems of artillery are critical for the accurate,efficient,and reliable delivery of pro-jectiles and propellants into the gun chamber.In modern artillery,the ammunition conveyor serves as the e... The automatic loading systems of artillery are critical for the accurate,efficient,and reliable delivery of pro-jectiles and propellants into the gun chamber.In modern artillery,the ammunition conveyor serves as the end effector of the automatic loading system,and its motion state significantly impacts the accuracy of projectiles.Therefore,it is of immense importance to precisely and effectively evaluate the reliability of the motion accuracy of the ammunition conveyor.This paper aims to propose a practical and efficient analysis method for evaluating the reliability of the motion accuracy of the ammunition conveyor.The proposed approach involves the use of a deep learning network to approximate the physical model and the extremum method to obtain a single cycle sequence decoupling strategy for solving the time-varying reliability issue of complex systems.Employing this strategy,the time-varying reliability of the ammunition conveyor is transformed into a static reliability problem.The proposed method includes the use of a deep feedforward neural network,second-order saddle point ap-proximation(SPA)method,extremum method,and efficient global optimization(EGO)technology.The results reveal that the reliability of the motion accuracy of the ammunition conveyor is 93.42%,with the maximum failure probability occurring at 0.21 s.These results serve as an important reference for the structural optimi-zation design of the ammunition conveyor based on reliability and the maintenance of the operational process. 展开更多
关键词 Automatic loading system Ammunition conveyor Motion accuracy RELIABILITY Second-order saddle point approximation
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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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Identification of small impact craters in Chang’e-4 landing areas using a new multi-scale fusion crater detection algorithm
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作者 FangChao Liu HuiWen Liu +7 位作者 Li Zhang Jian Chen DiJun Guo Bo Li ChangQing Liu ZongCheng Ling Ying-Bo Lu JunSheng Yao 《Earth and Planetary Physics》 2026年第1期92-104,共13页
Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious an... Impact craters are important for understanding the evolution of lunar geologic and surface erosion rates,among other functions.However,the morphological characteristics of these micro impact craters are not obvious and they are numerous,resulting in low detection accuracy by deep learning models.Therefore,we proposed a new multi-scale fusion crater detection algorithm(MSF-CDA)based on the YOLO11 to improve the accuracy of lunar impact crater detection,especially for small craters with a diameter of<1 km.Using the images taken by the LROC(Lunar Reconnaissance Orbiter Camera)at the Chang’e-4(CE-4)landing area,we constructed three separate datasets for craters with diameters of 0-70 m,70-140 m,and>140 m.We then trained three submodels separately with these three datasets.Additionally,we designed a slicing-amplifying-slicing strategy to enhance the ability to extract features from small craters.To handle redundant predictions,we proposed a new Non-Maximum Suppression with Area Filtering method to fuse the results in overlapping targets within the multi-scale submodels.Finally,our new MSF-CDA method achieved high detection performance,with the Precision,Recall,and F1 score having values of 0.991,0.987,and 0.989,respectively,perfectly addressing the problems induced by the lesser features and sample imbalance of small craters.Our MSF-CDA can provide strong data support for more in-depth study of the geological evolution of the lunar surface and finer geological age estimations.This strategy can also be used to detect other small objects with lesser features and sample imbalance problems.We detected approximately 500,000 impact craters in an area of approximately 214 km2 around the CE-4 landing area.By statistically analyzing the new data,we updated the distribution function of the number and diameter of impact craters.Finally,we identified the most suitable lighting conditions for detecting impact crater targets by analyzing the effect of different lighting conditions on the detection accuracy. 展开更多
关键词 impact craters Chang’e-4 landing area multi-scale automatic detection YOLO11 Fusion algorithm
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VMFD:Virtual Meetings Fatigue Detector Using Eye Polygon Area and Dlib Shape Indicator
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作者 Hafsa Sidaq Lei Wang +3 位作者 Sghaier Guizani Hussain Haider Ateeq Ur Rehman Habib Hamam 《Computers, Materials & Continua》 2026年第3期672-688,共17页
Numerous sectors,such as education,the IT sector,and corporate organizations,transitioned to virtual meetings after the COVID-19 crisis.Organizations now seek to assess participants’fatigue levels in online meetings ... Numerous sectors,such as education,the IT sector,and corporate organizations,transitioned to virtual meetings after the COVID-19 crisis.Organizations now seek to assess participants’fatigue levels in online meetings to remain competitive.Instructors cannot effectively monitor every individual in a virtual environment,which raises significant concerns about participant fatigue.Our proposed system monitors fatigue,identifying attentive and drowsy individuals throughout the online session.We leverage Dlib’s pre-trained facial landmark detector and focus on the eye landmarks only,offering a more detailed analysis for predicting eye opening and closing of the eyes,rather than focusing on the entire face.We introduce an Eye Polygon Area(EPA)formula,which computes eye activity from Dlib eye landmarks by measuring the polygonal area of the eye opening.Unlike the Eye Aspect Ratio(EAR),which relies on a single distance ratio,EPA adapts to different eye shapes(round,narrow,or wide),providing a more reliable measure for fatigue detection.The VMFD system issues a warning if a participant remains in a fatigued condition for 36 consecutive frames.The proposed technology is tested under multiple scenarios,including low-to high-lighting conditions(50-1400 lux)and both with and without glasses.This study builds an OpenCV application in Python,evaluated using the iBUG 300-W dataset,achieving 97.5%accuracy in detecting active participants.We compare VMFD with conventional methods relying on the EAR and show that the EPA technique performs significantly better. 展开更多
关键词 Fatigue detector human-computer interaction(HCI) eye blink active and inactive behavior online meeting automatic fatigue alert
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高黎贡山地区尤犀金龟属昆虫物种分子鉴定
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作者 付忠洪 尹晶 +4 位作者 段可怡 卢斐 易传辉 柳青 和秋菊 《云南农业大学学报(自然科学版)》 北大核心 2025年第3期28-35,共8页
【目的】应用线粒体DNA条形码技术对尤犀金龟属(Eupatorus Burmeister,1847)昆虫物种界定进行探索,以解决该属物种形态鉴定困难的问题。【方法】基于尤犀金龟属物种线粒体cox1和cox2基因序列数据集,使用Automatic Barcode Gap Discovery... 【目的】应用线粒体DNA条形码技术对尤犀金龟属(Eupatorus Burmeister,1847)昆虫物种界定进行探索,以解决该属物种形态鉴定困难的问题。【方法】基于尤犀金龟属物种线粒体cox1和cox2基因序列数据集,使用Automatic Barcode Gap Discovery(ABGD)和Bayesian Poisson Tree Processes(bPTP)对3个形态种进行分子物种界定,并与形态学鉴定结果进行比较。【结果】使用ABGD方法时,cox1数据集的界定结果与形态学鉴定结果一致,cox2数据集的界定结果与形态学鉴定结果存在差异;使用bPTP方法时,2种数据集的界定结果均远高于形态学鉴定结果,且均存在不同程度的过度划分。【结论】cox1是更适合用于鉴定尤犀金龟属昆虫的DNA条形码,使用ABGD方法时,其数据集界定结果与形态学鉴定结果一致。利用分子界定与形态特征鉴定相结合,可极大地提高鉴定效率和准确性。 展开更多
关键词 尤犀金龟属 分类 物种分子鉴定 cox1 Automatic Barcode Gap Discovery(ABGD)
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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:4
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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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Multi-modal intelligent situation awareness in real-time air traffic control: Control intent understanding and flight trajectory prediction 被引量:1
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作者 Dongyue GUO Jianwei ZHANG +1 位作者 Bo YANG Yi LIN 《Chinese Journal of Aeronautics》 2025年第6期41-57,共17页
With the advent of the next-generation Air Traffic Control(ATC)system,there is growing interest in using Artificial Intelligence(AI)techniques to enhance Situation Awareness(SA)for ATC Controllers(ATCOs),i.e.,Intellig... With the advent of the next-generation Air Traffic Control(ATC)system,there is growing interest in using Artificial Intelligence(AI)techniques to enhance Situation Awareness(SA)for ATC Controllers(ATCOs),i.e.,Intelligent SA(ISA).However,the existing AI-based SA approaches often rely on unimodal data and lack a comprehensive description and benchmark of the ISA tasks utilizing multi-modal data for real-time ATC environments.To address this gap,by analyzing the situation awareness procedure of the ATCOs,the ISA task is refined to the processing of the two primary elements,i.e.,spoken instructions and flight trajectories.Subsequently,the ISA is further formulated into Controlling Intent Understanding(CIU)and Flight Trajectory Prediction(FTP)tasks.For the CIU task,an innovative automatic speech recognition and understanding framework is designed to extract the controlling intent from unstructured and continuous ATC communications.For the FTP task,the single-and multi-horizon FTP approaches are investigated to support the high-precision prediction of the situation evolution.A total of 32 unimodal/multi-modal advanced methods with extensive evaluation metrics are introduced to conduct the benchmarks on the real-world multi-modal ATC situation dataset.Experimental results demonstrate the effectiveness of AI-based techniques in enhancing ISA for the ATC environment. 展开更多
关键词 Airtraffic control Automatic speechrecognition and understanding Flight trajectory prediction MULTI-MODAL Situationawareness
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Transformer-based identification for ADS-B transmitters in open–time sets 被引量:1
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作者 Yunfei ZHENG Xuejun ZHANG +1 位作者 Yuanhao TAN Xueyuan LI 《Chinese Journal of Aeronautics》 2025年第8期470-484,共15页
Radio Frequency Fingerprint Identification(RFFI)technology provides a means of identifying spurious signals.This technology has been widely used in solving Automatic Dependent Surveillance–Broadcast(ADS-B)signal spoo... Radio Frequency Fingerprint Identification(RFFI)technology provides a means of identifying spurious signals.This technology has been widely used in solving Automatic Dependent Surveillance–Broadcast(ADS-B)signal spoofing problems.However,the effects of circuit changes over time often lead to a decline in identification accuracy within open-time set.This paper proposes an ADS-B transmitter identification method to solve the degradation of identification accuracy.First,a real-time data processing system is established to receive and store ADS-B signals to meet the conditions for open-time set.The system possesses the following functionalities:data collection,data parsing,feature extraction,and identity recognition.Subsequently,a two-dimensional TimeFrequency Feature Diagram(TFFD)is proposed as a signal pre-processing method.The TFFD is constructed from the received ADS-B signal and the reconstructed signal for input to the recognition model.Finally,incorporating a frequency offset layer into the Swin Transformer architecture,a novel recognition network framework is proposed.This integration can enhance the network recognition accuracy and robustness by tailoring to the specific characteristics of ADSB signals.Experimental results indicate that the proposed recognition architecture achieves recognition accuracy of 95.86%in closed-time set and 84.33%in open-time set,surpassing other algorithms. 展开更多
关键词 Automatic Dependent Surveillance-Broadcast Radio frequency fingerprinting IDENTIFICATION Open-time set Time-frequency feature diagram Swin Transformer
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Modeling and control of automatic voltage regulation for a hydropower plant using advanced model predictive control 被引量:1
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作者 Ebunle Akupan Rene Willy Stephen Tounsi Fokui 《Global Energy Interconnection》 2025年第2期269-285,共17页
Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive cont... Fluctuating voltage levels in power grids necessitate automatic voltage regulators(AVRs)to ensure stability.This study examined the modeling and control of AVR in hydroelectric power plants using model predictive control(MPC),which utilizes an extensive mathe-matical model of the voltage regulation system to optimize the control actions over a defined prediction horizon.This predictive feature enables MPC to minimize voltage deviations while accounting for operational constraints,thereby improving stability and performance under dynamic conditions.Thefindings were compared with those derived from an optimal proportional integral derivative(PID)con-troller designed using the artificial bee colony(ABC)algorithm.Although the ABC-PID method adjusts the PID parameters based on historical data,it may be difficult to adapt to real-time changes in system dynamics under constraints.Comprehensive simulations assessed both frameworks,emphasizing performance metrics such as disturbance rejection,response to load changes,and resilience to uncertainties.The results show that both MPC and ABC-PID methods effectively achieved accurate voltage regulation;however,MPC excelled in controlling overshoot and settling time—recording 0.0%and 0.25 s,respectively.This demonstrates greater robustness compared to conventional control methods that optimize PID parameters based on performance criteria derived from actual system behavior,which exhibited settling times and overshoots exceeding 0.41 s and 5.0%,respectively.The controllers were implemented using MATLAB/Simulink software,indicating a significant advancement for power plant engineers pursuing state-of-the-art automatic voltage regulations. 展开更多
关键词 Automatic voltage regulation Artificial bee colony Evolutionary techniques Model predictive control PID controller HYDROPOWER
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Automatic identification of discontinuities and refined modeling of rock blocks from 3D point cloud data of rock surfaces 被引量:1
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作者 Yaopeng Ji Shengyuan Song +5 位作者 Jianping Chen Jingyu Xue Jianhua Yan Yansong Zhang Di Sun Qing Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3093-3106,共14页
The spatial distribution of discontinuities and the size of rock blocks are the key indicators for rock mass quality evaluation and rockfall risk assessment.Traditional manual measurement is often dangerous or unreach... The spatial distribution of discontinuities and the size of rock blocks are the key indicators for rock mass quality evaluation and rockfall risk assessment.Traditional manual measurement is often dangerous or unreachable at some high-steep rock slopes.In contrast,unmanned aerial vehicle(UAV)photogrammetry is not limited by terrain conditions,and can efficiently collect high-precision three-dimensional(3D)point clouds of rock masses through all-round and multiangle photography for rock mass characterization.In this paper,a new method based on a 3D point cloud is proposed for discontinuity identification and refined rock block modeling.The method is based on four steps:(1)Establish a point cloud spatial topology,and calculate the point cloud normal vector and average point spacing based on several machine learning algorithms;(2)Extract discontinuities using the density-based spatial clustering of applications with noise(DBSCAN)algorithm and fit the discontinuity plane by combining principal component analysis(PCA)with the natural breaks(NB)method;(3)Propose a method of inserting points in the line segment to generate an embedded discontinuity point cloud;and(4)Adopt a Poisson reconstruction method for refined rock block modeling.The proposed method was applied to an outcrop of an ultrahigh steep rock slope and compared with the results of previous studies and manual surveys.The results show that the method can eliminate the influence of discontinuity undulations on the orientation measurement and describe the local concave-convex characteristics on the modeling of rock blocks.The calculation results are accurate and reliable,which can meet the practical requirements of engineering. 展开更多
关键词 Three-dimensional(3D)point cloud Rock mass Automatic identification Refined modeling Unmanned aerial vehicle(UAV)
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False signal identification of ADS-B assisted by UAV cooperative localization 被引量:1
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作者 Yae CHAI Mingqian LIU +1 位作者 Weixing ZHENG Junlin ZHANG 《Chinese Journal of Aeronautics》 2025年第10期59-70,共12页
Automatic Dependent Surveillance-Broadcast(ADS-B)technology,with its open signal sharing,faces substantial security risks from false signals and spoofing attacks when broadcasting Unmanned Aerial Vehicle(UAV)informati... Automatic Dependent Surveillance-Broadcast(ADS-B)technology,with its open signal sharing,faces substantial security risks from false signals and spoofing attacks when broadcasting Unmanned Aerial Vehicle(UAV)information.This paper proposes a security position verification technique based on Multilateration(MLAT)to detect false signals,ensuring UAV safety and reliable airspace operations.First,the proposed method estimates the current position of the UAV by calculating the Time Difference of Arrival(TDOA),Time Sum of Arrival(TSOA),and Angle of Arrival(AOA)information.Then,this estimated position is compared with the ADS-B message to eliminate false UAV signals.Furthermore,a localization model based on TDOA/TSOA/AOA is established by utilizing reliable reference sources for base station time synchronization.Additionally,an improved Chan-Taylor algorithm is developed,incorporating the Constrained Weighted Least Squares(CWLS)method to initialize UAV position calculations.Finally,a false signal detection method is proposed to distinguish between true and false positioning targets.Numerical simulation results indicate that,at a positioning error threshold of 150 m,the improved Chan-Taylor algorithm based on TDOA/TSOA/AOA achieves 100%accuracy coverage,significantly enhancing localization precision.And the proposed false signal detection method achieves a detection accuracy rate of at least 90%within a 50-meter error range. 展开更多
关键词 Automatic dependent surveillance-broadcast(ADS-B) Cooperative localization False signal identification Multilateration(MLAT) Unmanned aerial vehicle(UAV)
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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass 被引量:1
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection Digital joint mapping Rock discontinuities characterization Three-dimensional(3D)trace network
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Impact of Single-Phase Automatic Recloser of Critical Transmission Line on the Stability of the Power Transmission Network
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作者 Chuulan Natsagdorj Ganbat Gantamir Erdenebileg Doljinsuren 《Journal of Power and Energy Engineering》 2025年第2期43-56,共14页
In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220... In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults. 展开更多
关键词 Automatic Reclosing Single-Phase Automatic Reclosing Relay Protection Overhead Power Lines System Stability Rotor Angle Stability
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Implementing Convolutional Neural Networks to Detect Dangerous Objects in Video Surveillance Systems
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作者 Carlos Rojas Cristian Bravo +1 位作者 Carlos Enrique Montenegro-Marín Rubén González-Crespo 《Computers, Materials & Continua》 2025年第12期5489-5507,共19页
The increasing prevalence of violent incidents in public spaces has created an urgent need for intelligent surveillance systems capable of detecting dangerous objects in real time.While traditional video surveillance ... The increasing prevalence of violent incidents in public spaces has created an urgent need for intelligent surveillance systems capable of detecting dangerous objects in real time.While traditional video surveillance relies on human monitoring,this approach suffers from limitations such as fatigue and delayed response times.This study addresses these challenges by developing an automated detection system using advanced deep learning techniques to enhance public safety.Our approach leverages state-of-the-art convolutional neural networks(CNNs),specifically You Only Look Once version 4(YOLOv4)and EfficientDet,for real-time object detection.The system was trained on a comprehensive dataset of over 50,000 images,enhanced through data augmentation techniques to improve robustness across varying lighting conditions and viewing angles.Cloud-based deployment on Amazon Web Services(AWS)ensured scalability and efficient processing.Experimental evaluations demonstrated high performance,with YOLOv4 achieving 92%accuracy and processing images in 0.45 s,while EfficientDet reached 93%accuracy with a slightly longer processing time of 0.55 s per image.Field tests in high-traffic environments such as train stations and shopping malls confirmed the system’s reliability,with a false alarm rate of only 4.5%.The integration of automatic alerts enabled rapid security responses to potential threats.The proposed CNN-based system provides an effective solution for real-time detection of dangerous objects in video surveillance,significantly improving response times and public safety.While YOLOv4 proved more suitable for speed-critical applications,EfficientDet offered marginally better accuracy.Future work will focus on optimizing the system for low-light conditions and further reducing false positives.This research contributes to the advancement of AI-driven surveillance technologies,offering a scalable framework adaptable to various security scenarios. 展开更多
关键词 Automatic detection of objects convolutional neural networks deep learning real-time image processing video surveillance systems automatic alerts
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Plasticity,Contingency,and Virtuality in the Age of Automatic Reproduction
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作者 Szymon Wróbel 《Philosophy Study》 2025年第4期135-144,共10页
In this paper,the author follows the trail of C.Malabou,Q.Meillassoux,and G.Deleuze and tries to test three philosophical concepts that seem to be particularly threatened in the era of automatic digital reproduction.T... In this paper,the author follows the trail of C.Malabou,Q.Meillassoux,and G.Deleuze and tries to test three philosophical concepts that seem to be particularly threatened in the era of automatic digital reproduction.These three concepts are plasticity(defended for many years by C.Malabou),contingency(reconstructed by Q.Meillassoux),and virtuality(developed by G.Deleuze).The main task of the text will be to reflect on which of these three concepts better protects our thinking against automation and stays faithful to the ideal of creativity.In what sense are plasticity,contingency,and the possibility of virtualization the a priori condition of any transformation,physical or intellectual,affective or conceptual metamorphosis?In what sense are these three concepts the only conditions for the survival of every living being?Would a being without contingency,plasticity,and disposition to virtualization simply be a dead being? 展开更多
关键词 automatic society CONTINGENCY PLASTICITY technical reproduction VIRTUALIZATION
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Self-compassion,automatic thoughts,and mental pain in depression:Mediating effects and clinical implications
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作者 Li-Na Ren Ji-Song Pang +6 位作者 Qiao-Na Jiang Xiao-Fei Zhang Lu-Lu Li Jing Wang Jian-Gong Li Yan-Yan Ma Wei Jia 《World Journal of Psychiatry》 2025年第4期207-215,共9页
BACKGROUND Depression is a leading global health concern with high suicide rates and recurrence.Cognitive models suggest that mental pain and automatic thoughts are central to depression's impact.The hypothesis is... BACKGROUND Depression is a leading global health concern with high suicide rates and recurrence.Cognitive models suggest that mental pain and automatic thoughts are central to depression's impact.The hypothesis is that self-compassion will be negatively associated with mental pain,mediated by automatic thoughts.AIM To determine the mediating role of automatic thoughts in the relationship between self-compassion and mental pain in individuals with depression.METHODS This cross-sectional study included 389 inpatients with depression from Tianjin Anding Hospital.Participants completed the Self-Compassion Scale-Chinese Version(SCS-C),Automatic Thought Questionnaire(ATQ),and Orbach&Mikulincer Mental Pain Scale-Chinese Version(OMMP).Data were analyzed using Pearson correlations,multiple linear regressions,and mediation analysis.RESULTS The SCS-C total score was 68.95±14.89,ATQ was 87.02±28.91,and OMMP was 129.01±36.74.Correlation analysis showed mental pain was positively associated with automatic thoughts(r=0.802,P<0.001)and negatively with selfcompassion(r=-0.636,P<0.001).Regression analysis indicated automatic thoughts(β=0.623,P<0.001)and self-compassion(β=-0.301,P<0.001)significantly predicted mental pain.Mediation analysis confirmed automatic thoughts partially mediated the relationship between self-compassion and mental pain(ab=-0.269,95%CI:-0.363 to-0.212).CONCLUSION Self-compassion is inversely related to mental pain in depression,with automatic thoughts playing a mediating role.These findings suggest potential therapeutic targets for alleviating mental pain in depressed patients. 展开更多
关键词 SELF-COMPASSION Automatic thoughts Mental pain DEPRESSION Mediation analysis
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