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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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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method 被引量:1
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作者 Yi-Sheng Hao Zhen Wu +3 位作者 Shen-Shen Gao Rui Qiu Hui Zhang Jun-Li Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期200-215,共16页
Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS m... Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program MCShield.The proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation example.The results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% reduction.This demonstrates that the grid-AIS method is effective in addressing global issues.The results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational results.Moreover,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method. 展开更多
关键词 Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling
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Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios 被引量:1
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作者 Xiaolin Tang Yuyou Yang +3 位作者 Teng Liu Xianke Lin Kai Yang Shen Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期181-195,共15页
Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adja... Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees. 展开更多
关键词 Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)
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An inverse analysis of fluid flow through granular media using differentiable lattice Boltzmann method 被引量:1
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作者 Qiuyu Wang Krishna Kumar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2077-2090,共14页
This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeabi... This study presents a method for the inverse analysis of fluid flow problems.The focus is put on accurately determining boundary conditions and characterizing the physical properties of granular media,such as permeability,and fluid components,like viscosity.The primary aim is to deduce either constant pressure head or pressure profiles,given the known velocity field at a steady-state flow through a conduit containing obstacles,including walls,spheres,and grains.The lattice Boltzmann method(LBM)combined with automatic differentiation(AD)(AD-LBM)is employed,with the help of the GPU-capable Taichi programming language.A lightweight tape is used to generate gradients for the entire LBM simulation,enabling end-to-end backpropagation.Our AD-LBM approach accurately estimates the boundary conditions for complex flow paths in porous media,leading to observed steady-state velocity fields and deriving macro-scale permeability and fluid viscosity.The method demonstrates significant advantages in terms of prediction accuracy and computational efficiency,making it a powerful tool for solving inverse fluid flow problems in various applications. 展开更多
关键词 Inverse problem Fluid flow Granular media Automatic differentiation(AD) Lattice Boltzmann method(LBM)
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Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction 被引量:1
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作者 Yangtian Liu Xiaopeng Yan +2 位作者 Qiang Liu Tai An Jian Dai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期328-338,共11页
The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-n... The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs. 展开更多
关键词 Automatic modulation recognition Adaptive denoising Data rearrangement and the 2D FFT(DR2D) Radio fuze
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A High Resolution Convolutional Neural Network with Squeeze and Excitation Module for Automatic Modulation Classification
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作者 Duan Ruifeng Zhao Yuanlin +3 位作者 Zhang Haiyan Li Xinze Cheng Peng Li Yonghui 《China Communications》 SCIE CSCD 2024年第10期132-147,共16页
Automatic modulation classification(AMC) technology is one of the cutting-edge technologies in cognitive radio communications. AMC based on deep learning has recently attracted much attention due to its superior perfo... Automatic modulation classification(AMC) technology is one of the cutting-edge technologies in cognitive radio communications. AMC based on deep learning has recently attracted much attention due to its superior performances in classification accuracy and robustness. In this paper, we propose a novel, high resolution and multi-scale feature fusion convolutional neural network model with a squeeze-excitation block, referred to as HRSENet,to classify different kinds of modulation signals.The proposed model establishes a parallel computing mechanism of multi-resolution feature maps through the multi-layer convolution operation, which effectively reduces the information loss caused by downsampling convolution. Moreover, through dense skipconnecting at the same resolution and up-sampling or down-sampling connection at different resolutions, the low resolution representation of the deep feature maps and the high resolution representation of the shallow feature maps are simultaneously extracted and fully integrated, which is benificial to mine signal multilevel features. Finally, the feature squeeze and excitation module embedded in the decoder is used to adjust the response weights between channels, further improving classification accuracy of proposed model.The proposed HRSENet significantly outperforms existing methods in terms of classification accuracy on the public dataset “Over the Air” in signal-to-noise(SNR) ranging from-2dB to 20dB. The classification accuracy in the proposed model achieves 85.36% and97.30% at 4dB and 10dB, respectively, with the improvement by 9.71% and 5.82% compared to LWNet.Furthermore, the model also has a moderate computation complexity compared with several state-of-the-art methods. 展开更多
关键词 automatic modulation classification deep learning feature squeeze-and-excitation HIGH-RESOLUTION MULTI-SCALE
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Construction Activity Analysis of Workers Based on Human Posture Estimation Information
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作者 Xuhong Zhou Shuai Li +2 位作者 Jiepeng Liu Zhou Wu Yohchia Frank Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期225-236,共12页
Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely... Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency. 展开更多
关键词 Pose estimation Activity analysis Object tracking Construction workers Automatic systems
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Automatic fovea detection and choroid segmentation for choroidal thickness assessment in optical coherence tomography
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作者 Chen Yu Lin Hung Ju Chen +3 位作者 Yi Kit Chan Wei Ping Hsia Yu Len Huang Chia Jen Chang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1763-1771,共9页
AIM:To develop an automated model for subfoveal choroidal thickness(SFCT)detection in optical coherence tomography(OCT)images,addressing manual fovea location and choroidal contour challenges.METHODS:Two procedures we... AIM:To develop an automated model for subfoveal choroidal thickness(SFCT)detection in optical coherence tomography(OCT)images,addressing manual fovea location and choroidal contour challenges.METHODS:Two procedures were proposed:defining the fovea and segmenting the choroid.Fovea localization from B-scan OCT image sequence with three-dimensional reconstruction(LocBscan-3D)predicted fovea location using central foveal depression features,and fovea localization from two-dimensional en-face OCT(LocEN-2D)used a mask region-based convolutional neural network(Mask R-CNN)model for optic disc detection,and determined the fovea location based on optic disc relative position.Choroid segmentation also employed Mask R-CNN.RESULTS:For 53 eyes in 28 healthy subjects,LocBscan-3D’s mean difference between manual and predicted fovea locations was 170.0μm,LocEN-2D yielded 675.9μm.LocEN-2D performed better in non-high myopia group(P=0.02).SFCT measurements from Mask R-CNN aligned with manual values.CONCLUSION:Our models accurately predict SFCT in OCT images.LocBscan-3D excels in precise fovea localization even with high myopia.LocEN-2D shows high detection rates but lower accuracy especially in the high myopia group.Combining both models offers a robust SFCT assessment approach,promising efficiency and accuracy for large-scale studies and clinical use. 展开更多
关键词 subfoveal choroidal thickness optical coherence tomography automatic foveal detection automatic choroid segmentation
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The 18th Workshop on Antarctic Meteorology and Climate
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作者 Anastasia J.TOMANEK Ethan J.KOUDELKA +4 位作者 Mariana F.LITELL Taylor P.NORTON Mckenzie J.DICE Isabella I.ONSI Matthew A.LAZZARA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第12期2495-2504,共10页
The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of W... The 18th Workshop on Antarctic Meteorology and Climate was held on 31 May through 2 June 2023.The Antarctic Meteorological Research and Data Center hosted this hybrid workshop at the Pyle Center at the University of Wisconsin-Madison in Madison,WI,USA.Global members of the Antarctic meteorological community gathered to present and discuss topics from scientific research to operational support within Antarctic meteorology and climate.Students and early career professionals chaired various presentations and discussions while all attendees engaged to share results,build collaborative plans,and discuss further developments.The main workshop topics included updates on the current Automatic Weather Station(AWS)networks,challenges,and planning concerning Antarctic forecasting and operational services,Antarctic numerical modeling systems,observational applications and research,and Antarctic community and data sources.Across six sessions,over 25 different presenters elaborated on their work in areas such as field season updates,atmospheric rivers,remote sensing,the Antarctic Mesoscale Prediction System(AMPS),and forecasting challenges due to data scarcity.Workshop discussions resulted in several key outcomes and action items regarding fieldwork impacts,exploration of field techniques,observation coverage,and communication between operations and research scientists.Future workshops will provide opportunities for continued discussion on the evolution of the AWS network and operational needs while providing a venue to promote collaboration and cooperation for Antarctic meteorology and climate activities. 展开更多
关键词 ANTARCTICA polar meteorology automatic weather station polar modeling polar climatology
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A Retrodirective Array Enabled by CMOS Chips for Two-Way Wireless Communication with Automatic Beam Tracking
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作者 Jiacheng Guo Yizhu Shen +2 位作者 Guoqing Dong Zhuang Han Sanming Hu 《Engineering》 SCIE EI CAS CSCD 2024年第6期196-207,共12页
This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam tracking.The proposed RDA is enabled by specifically designed chips made using a domestic comple... This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam tracking.The proposed RDA is enabled by specifically designed chips made using a domestic complementary metal-oxide semiconductor(CMOS)process.The highly integrated CMOS chip includes a receiving(Rx)chain,a transmitting(Tx)chain,and a unique tracking phaselocked loop(PLL)for the crucial conjugated phase recovery in the RDA.This article also proposes a method to reduce the beam pointing error(BPE)in a conventional RDA.To validate the above ideas simply yet without loss of generality,a 2.4 GHz RDA is demonstrated through two-way communication links between the Rx and Tx chains,and an on-chip quadrature coupler is designed to achieve a nonretrodirective signal suppression of 23 dBc.The experimental results demonstrate that the proposed RDA,which incorporates domestically manufactured low-cost 0.18 lm CMOS chips,is capable of automatically tracking beams covering±40with a reduced BPE.Each CMOS chip in the RDA has a compact size of 4.62 mm^(2) and a low power consumption of 0.15 W.To the best of the authors’knowledge,this is the first research to demonstrate an RDA with a fully customized CMOS chip for wireless communication with automatic beam tracking。 展开更多
关键词 Automatic beam tracking CMOS Retrodirective array Two-way communication
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Extreme Antarctic Cold of Late Winter 2023
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作者 Anastasia J.TOMANEK David E.MIKOLAJCZYK +7 位作者 Matthew A.LAZZARA Stefano DI BATTISTA Minghu DING Mariana FONTOLAN LITELL David H.BROMWICH Taylor P.NORTON Linda M.KELLER Lee J.WELHOUSE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1873-1880,共8页
Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Ai... Extreme cold temperatures were observed in July and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely impacted.Specifically,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the aircraft.The cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low temperatures.Four separate cold phases were identified,each a few days in duration and occurring from mid-July to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold temperatures.The monthly 500-hPa geopotential height anomalies show strong negative anomalies in August.Examination of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric conditions.Understanding the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology. 展开更多
关键词 ANTARCTICA extreme cold temperature automatic weather station networks
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Automatic detection method of bladder tumor cells based on color and shape features
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作者 Zitong Zhao Yanbo Wang +6 位作者 Jiaqi Chen Mingjia Wang Shulong Feng Jin Yang Nan Song Jinyu Wang Ci Sun 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第6期1-13,共13页
Bladder urothelial carcinoma is the most common malignant tumor disease in urinary system,and its incidence rate ranks ninth in the world.In recent years,the continuous development of hyperspectral imaging technology ... Bladder urothelial carcinoma is the most common malignant tumor disease in urinary system,and its incidence rate ranks ninth in the world.In recent years,the continuous development of hyperspectral imaging technology has provided a new tool for the auxiliary diagnosis of bladder cancer.In this study,based on microscopic hyperspectral data,an automatic detection algorithm of bladder tumor cells combining color features and shape features is proposed.Support vector machine(SVM)is used to build classification models and compare the classification performance of spectral feature,spectral and shape fusion feature,and the fusion feature proposed in this paper on the same classifier.The results show that the sensitivity,specificity,and accuracy of our classification algorithm based on shape and color fusion features are 0.952,0.897,and 0.920,respectively,which are better than the classification algorithm only using spectral features.Therefore,this study can effectively extract the cell features of bladder urothelial carcinoma smear,thus achieving automatic,real-time,and noninvasive detection of bladder tumor cells,and then helping doctors improve the efficiency of pathological diagnosis of bladder urothelial cancer,and providing a reliable basis for doctors to choose treatment plans and judge the prognosis of the disease. 展开更多
关键词 Bladder tumor cells microscopic hyperspectral fusion feature support vector machine automatic detection.
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FPGA-based plasma sterilization device for wound-edge recognition
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作者 Huijuan Lu Xiaorong Tang +3 位作者 Minglei Li Xueping Jiang Wenxiang Xiao Hua Li 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第3期56-70,共15页
There is a currently a lack of large-area plasma sterilization devices that can intelligently identify the shape of a wound for automatic steriliza-tion.For this reason,in this work,a plasma sterilization device with ... There is a currently a lack of large-area plasma sterilization devices that can intelligently identify the shape of a wound for automatic steriliza-tion.For this reason,in this work,a plasma sterilization device with wound-edge recognition was developed using afield-programmable gate array(FPGA)and a high-performance image-processing platform to realize intelligent and precise sterilization of wounds.SOLIDWORKS was used to design the mechanical structure of the device,and it was manufactured using 3D printing.The device used an improvement of the traditional Sobel detection algorithm,which extends the detection of edges in only the x and y directions to eight directions(0○,45○,90○,135○,180○,225○,270○,and 315○),completing the wound-edge detection by adaptive thresholding.The device can be controlled according to different shapes of sterilization area to adjust the positioning of a single plasma-jet tube in the horizontal plane for two-dimensional move-ment;the distance between the plasma-jet tube and the surface of the object to be sterilized can be also adjusted in the vertical direction.In this way,motors are used to move the plasma jet and achieve automatic,efficient,and accurate plasma sterilization.It was found that a good sterilization effect could be achieved at both the culture-medium level and the biological-tissue level.The ideal sterilization parameters at the culture-medium level were a speed of 2 mm/s and aflow rate of 0.6 slm,while at the biological-tissue level,these values were 1 mm/s and 0.6 slm,respectively. 展开更多
关键词 FPGA Wound-edge recognition Improvement of the Sobel algorithm PLASMA Automatic and precise sterilization
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Deep Structure Optimization for Incremental Hierarchical Fuzzy Systems Using Improved Differential Evolution Algorithm
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作者 Yue Zhu Tao Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1139-1158,共20页
The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) a... The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) and thecorrelation of each sub fuzzy system, the uncertainty of the HFS’s deep structure increases. For the HFS, a largenumber of studies mainly use fixed structures, which cannot be selected automatically. To solve this problem, thispaper proposes a novel approach for constructing the incremental HFS. During system design, the deep structureand the rule base of the HFS are encoded separately. Subsequently, the deep structure is adaptively mutated basedon the fitness value, so as to realize the diversity of deep structures while ensuring reasonable competition amongthe structures. Finally, the differential evolution (DE) is used to optimize the deep structure of HFS and theparameters of antecedent and consequent simultaneously. The simulation results confirm the effectiveness of themodel. Specifically, the root mean square errors in the Laser dataset and Friedman dataset are 0.0395 and 0.0725,respectively with rule counts of rules is 8 and 12, respectively.When compared to alternative methods, the resultsindicate that the proposed method offers improvements in accuracy and rule counts. 展开更多
关键词 Hierarchical fuzzy system automatic optimization differential evolution regression problem
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Research on Automatic Test System of Engine Blade Natural Frequency
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作者 LU Yonghua LIU Jingjing +2 位作者 YANG Haibo HUANG Chuan MA Zhicheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期476-487,共12页
Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequ... Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequency before installing them on the engine to avoid resonance.At present,most blade vibration testing systems require manual operation by operators,which has high requirements for operators and the testing process is also very cumbersome.Therefore,the testing efficiency is low and cannot meet the needs of efficient testing.To solve the current problems of low testing efficiency and high operational requirements,a high-precision and high-efficiency automatic test system is designed.The testing accuracy of this system can reach ±1%,and the testing efficiency is improved by 37% compared to manual testing.Firstly,the influence of compression force and vibration exciter position on natural frequency test is analyzed by amplitude-frequency curve,so as to calibrate servo cylinder and fourdimensional motion platform.Secondly,the sine wave signal is used as the excitation to sweep the blade linearly,and the natural frequency is determined by the amplitude peak in the frequency domain.Finally,the accuracy experiment and efficiency experiment are carried out on the developed test system,whose results verify its high efficiency and high precision. 展开更多
关键词 BLADE vibration failure natural frequency automatic test system
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Automatic modulation recognition of radiation source signals based on two-dimensional data matrix and improved residual neural network
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作者 Guanghua Yi Xinhong Hao +3 位作者 Xiaopeng Yan Jian Dai Yangtian Liu Yanwen Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期364-373,共10页
Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the ... Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the AMR method of radiation source signals based on two-dimensional data matrix and improved residual neural network is proposed in this paper.First,the time series of the radiation source signals are reconstructed into two-dimensional data matrix,which greatly simplifies the signal preprocessing process.Second,the depthwise convolution and large-size convolutional kernels based residual neural network(DLRNet)is proposed to improve the feature extraction capability of the AMR model.Finally,the model performs feature extraction and classification on the two-dimensional data matrix to obtain the recognition vector that represents the signal modulation type.Theoretical analysis and simulation results show that the AMR method based on two-dimensional data matrix and improved residual network can significantly improve the accuracy of the AMR method.The recognition accuracy of the proposed method maintains a high level greater than 90% even at -14 dB SNR. 展开更多
关键词 Automatic modulation recognition Radiation source signals Two-dimensional data matrix Residual neural network Depthwise convolution
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Bearing mechanism of roof and rib support structure in automatically formed roadway and its support design method
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作者 JIANG Bei WANG Ming-zi +4 位作者 WANG Qi XIN Zhong-xin XING Xue-yang DENG Yu-song YAO Liang-di 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2467-2487,共21页
Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway excavation.The stability control of automatically formed roadway is the key to the succ... Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway excavation.The stability control of automatically formed roadway is the key to the successful application of the new method.In order to realize the stability control of the roadway surrounding rock,the mechanical model of the roof and rib support structure is established,and the influence mechanism of the automatically formed roadway parameters on the compound force is revealed.On this basis,the roof and rib support structure technology of confined lightweight concrete is proposed,and its mechanical tests under different eccentricity are carried out.The results show that the bearing capacity of confined lightweight concrete specimens is basically the same as that of ordinary confined concrete specimens.The bearing capacity of confined lightweight concrete specimens under different eccentricities is 1.95 times higher than those of U-shaped steel specimens.By comparing the test results with the theoretical calculated results of the confined concrete,the calculation method of the bearing capacity for the confined lightweight concrete structure is selected.The design method of confined lightweight concrete support structure is established,and is successfully applied in the extra-large mine,Ningtiaota Coal Mine,China. 展开更多
关键词 automatically roadway with non-pillar confined lightweight concrete roof and rib support mechanical model bearing behaviour
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A Dual Source Power Based EV Wireless Charging System
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作者 NAQVI Syed Zohair Raza XIAO Lan JIANG Menghan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期35-42,共8页
Recently,there has been a huge increase in the usage of fuel resources for automobiles which is severely affecting the climate and causing global warming.The use of electric vehicle(EV)is an effective way to protect t... Recently,there has been a huge increase in the usage of fuel resources for automobiles which is severely affecting the climate and causing global warming.The use of electric vehicle(EV)is an effective way to protect the environment and reduce travel costs.However,the EV charging system has a single charging source,and the charging rate is limited.In this paper,an EV wireless charging system based on dual source power supply has been developed.It realizes intelligent switching between 12 V photovoltaic output and 220 V AC dual source power,and has wireless transmission function.Based on the proposed power supply architecture,the micro wireless charging model is built,which enables the EV model to store power and realize static and mobile control through the wireless induction charging system. 展开更多
关键词 renewable energy inductive coupling inductive charging CONVERTERS automatic changeover auto cutoff circuit
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Multiscale and Auto-Tuned Semi-Supervised Deep Subspace Clustering and Its Application in Brain Tumor Clustering
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作者 Zhenyu Qian Yizhang Jiang +4 位作者 Zhou Hong Lijun Huang Fengda Li Khin Wee Lai Kaijian Xia 《Computers, Materials & Continua》 SCIE EI 2024年第6期4741-4762,共22页
In this paper,we introduce a novel Multi-scale and Auto-tuned Semi-supervised Deep Subspace Clustering(MAS-DSC)algorithm,aimed at addressing the challenges of deep subspace clustering in high-dimensional real-world da... In this paper,we introduce a novel Multi-scale and Auto-tuned Semi-supervised Deep Subspace Clustering(MAS-DSC)algorithm,aimed at addressing the challenges of deep subspace clustering in high-dimensional real-world data,particularly in the field of medical imaging.Traditional deep subspace clustering algorithms,which are mostly unsupervised,are limited in their ability to effectively utilize the inherent prior knowledge in medical images.Our MAS-DSC algorithm incorporates a semi-supervised learning framework that uses a small amount of labeled data to guide the clustering process,thereby enhancing the discriminative power of the feature representations.Additionally,the multi-scale feature extraction mechanism is designed to adapt to the complexity of medical imaging data,resulting in more accurate clustering performance.To address the difficulty of hyperparameter selection in deep subspace clustering,this paper employs a Bayesian optimization algorithm for adaptive tuning of hyperparameters related to subspace clustering,prior knowledge constraints,and model loss weights.Extensive experiments on standard clustering datasets,including ORL,Coil20,and Coil100,validate the effectiveness of the MAS-DSC algorithm.The results show that with its multi-scale network structure and Bayesian hyperparameter optimization,MAS-DSC achieves excellent clustering results on these datasets.Furthermore,tests on a brain tumor dataset demonstrate the robustness of the algorithm and its ability to leverage prior knowledge for efficient feature extraction and enhanced clustering performance within a semi-supervised learning framework. 展开更多
关键词 Deep subspace clustering multiscale network structure automatic hyperparameter tuning SEMI-SUPERVISED medical image clustering
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