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Steel surface defect detection based on lightweight YOLOv7

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Optoelectronics Letters 2025年

作者： shi tao Wu Rongxin Zhu Wenxu Ma Qingliang School of Electrical Engineering and Automation， Tianjin University of Technology North China University of Science and Technology， College of Electrical Engineering Guangzhou Institute of Measurement and Testing Technology

Aiming at the problems of low detection efficiency and difficult positioning of traditional steel surface defect detection methods， a lightweight steel surface defect detection model based on YOLOv7 is proposed. First， a CSS Block module is proposed， which uses more lightweight operations to obtain redundant information in the feature map， reduces the amount of computation， and effectively improves the detection speed. Secondly， the improved SPPCSPC structure is adopted to ensure that the model can also pay attention to the defect location information while predicting the defect category information， obtain richer defect features. In addition， the convolution operation in the original model is simplified， which significantly reduces the size of the model and helps to improve the detection speed. Finally， using EIOU Loss to focus on high-quality Anchors， speed up convergence and improve positioning accuracy. Experiments were carried out on the NEU-DET steel surface defect dataset. Compared with the original YOLOv7 model， the number of parameters of this model was reduced by 40%， the FPS reached 112， and the average accuracy reached 79.1%.， the detection accuracy and speed have been improved， which can meet the needs of steel surface defect detection.

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EBD-YOLO：a lightweight auxiliary driving detection algorithm based on YOLOv5

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Optoelectronics Letters 2025年

作者： SUN Lianshuai shi tao DING Yao LI Song Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems， School of Electrical Engineer-ing and Automation， Tianjin University of Technology College of Electrical Engineering， North China University of Science and Technology

A lightweight road-assistant detection algorithm， EBD-YOLO， based on YOLOv5s is proposed to address the problems of high model complexity， computation cost， and difficulty in deployment on resource-limited embedded terminals in existing assisted driving detection algorithms. First， lightweight Transformer model EfficientViT was used as the backbone feature extraction network of YOLOv5s model to reduce network parameters and calculation costs. Secondly， a Focal-GIoU Loss function is proposed for bounding box regression to accelerate model convergence and reduce loss. Thirdly， the feature pyramid structure is improved to a weighted bi-directional feature pyramid network (BiFPN) to enhance localization and semantic features. Then， a dynamic head framework is added to unify the attention mechanism with the object detection head to improve its performance. Finally， a Soft-CIoU＿NMS algorithm is proposed in the post-processing stage to enhance occluded targets' localization and detection ability and reduce the missed detection rate. We conducted experiments on the KITTI and BDD100K datasets for autonomous driving， and the results showed that the EBD-YOLO model reduced in size by 38.4% and 37.2%， respectively. In comparison， the computational cost was reduced by 48.1%. As measured by mAP@0.5， the detection accuracy improved by 0.5% and 5.8%， respectively， and mAP@0.5:0.95 improved by 2.8% and 7%， respectively. These improvements satisfied the requirements for deployment on embedded terminals in cars.

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Dynamic event-triggered data-driven iterative learning bipartite tracking control for nonlinear MASs with prescribed performance

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Science China(Information Sciences) 2025年第1期 292-305页

作者： tao shi Wei-Wei CHE School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

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Microwave dielectric properties and microstructure of a new kind Eu-based Eu(Mg_(0.5)Ti_(0.5))O_3 ceramic

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Rare Metals 2018年第11期37卷 913-918页

作者： tao shi Jing Zhu National Center for Electron Microscopy in Beijing Tsinghua University School of Materials Science and Engineering Tsinghua University The State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Laboratory of Advanced Materials Tsinghua University

A new Eu-based microwave dielectric ceramic,Eu(MgTi)O(EMT for short), was prepared through conventional solid-state reactions. The EMT ceramics were well densified at 1425 ℃ and exhibit good microwave dielectric properties with permittivity of 23.92, high quality factor(Q*f) of 66,957 GHz at 8.93 GHz and relatively low-temperature coefficient of resonant frequency of-20.3 10/K. Additionally, the variations of dielectric constants among Ln(MgTi)O(Ln represents rare earth elements, LMT) compounds were analyzed. Ionic radii of Ln, associated with the tolerance factors of the perovskite structure of LMT, were investigated to be the key factor to influence the permittivity. These results indicate that EMT ceramics might be one of the promising candidates as microwave resonators.

关键词： Microwave dielectrics Eu(Mg_(0.5)Ti_(0.5))O_3 Complex perovskite Solid-state reactions

A time and charge measurement board for muon tomography of high-Z materials

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Nuclear Science and Techniques 2017年第3期28卷 104-108页

作者： shi-tao Xiang Hao Liang State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

In this paper, a versatile time and charge measurement(MQT) board for muon tomography is described in detail. For time measurement, the general-purpose timeto-digital converter(TDC) chip TDC-GP2 is employed,while for charge measurement, digitization plus numerical integration in field programmable gate array is *** tests demonstrate that the total 32 channels of two MQT boards have a time resolution of superior than100 ps, with excellent linearity for time and charge measurement.

关键词： Time and charge measurement Generalpurpose time-to-digital converter (TDC-GP2) Muon tomography

Motional n-phonon bundle states of a trapped atom with clock transitions

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Photonics Research 2021年第7期9卷 1289-1299页

作者： YUANGANG DENG tao shi SU YI Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-sen University(Zhuhai Campus)Zhuhai 519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

Quantum manipulation of individual phonons could offer new resources for studying fundamental physics and creating an innovative platform in quantum information science. Here,we propose to generate quantum states of strongly correlated phonon bundles associated with the motion of a trapped atom. Our scheme operates in the atom–phonon resonance regime where the energy spectrum exhibits strong anharmonicity such that energy eigenstates with different phonon numbers can be well-resolved in the parameter space. Compared to earlier schemes operating in the far dispersive regime,the bundle states generated here contain a large steady-state phonon number. Therefore,the proposed system can be used as a high-quality multiphonon source. Our results open up the possibility of using long-lived motional phonons as quantum resources,which could provide a broad physics community for applications in quantum metrology.

关键词： phonon bundle quantum

Some Sufficient Conditions on the Number of Non-abelian Subgroups of a Finite Group to be Solvable

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Acta Mathematica Sinica,English Series 2011年第5期27卷 891-896页

作者： Jiang tao shi Cui ZHANG LMAM & School of Mathematical Sciences Peking University Beijing 100871 P. R. China University of Primorska FAMNIT Glagoljaska 8 6000 Koper Slovenia University of Primorska PINT Muzejski trg 2 6000 Koper Slovenia

Thompson＇s theorem indicates that a finite group with a nilpotent maximal subgroup of odd order is solvable. As an important application of Thompson＇s theorem, a finite group is solvable if it has an abelian maximal subgroup. In this paper, we give some sufficient conditions on the number of non-abelian subgroups of a finite group to be solvable.

关键词： Finite group abelian subgroup solvable group

Quantum statistics of phonon radiations in optomechanical systems

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Communications in Theoretical Physics 2022年第11期74卷 90-97页

作者： Menghan Chen Yue Chang tao shi CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Automation Control Equipment Institute Beijing 100074China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

We study the correlation statistics of phonon radiations in a weakly driven optomechanical *** dominated scattering processes are identified by the scattering theory analytically and the master equation numerically,whose interplay determines the phonon statistical *** results show that for the large detuning,the driving field off-resonant with the system induces a small emission rate of two anti-bunched *** the resonant driving field,there is a relatively large emission rate of two bunched phonons.

关键词： quantum optics optomechanics quantum information

Numerical Study on Characteristics of Supercavitating Flow Around the Variable-Lateral-Force Cavitator

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China Ocean Engineering 2017年第1期31卷 123-129页

作者： HU Xiao GAO Ye shi Xiao-tao College of Hydraulic and Environmental Engineering China Three Gorges University Yichang 443008 China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of Education China Three Gorges University Yichang 443008 China Department of Aerospace and Building Engineering Harbin Engineering University Harbin 150001 China

A control scheme named the variable-lateral-force cavitator, which is focused on the control of lift force, drag force and lateral forces for underwater supercavity vehicles was proposed, and the supercavitating flow around the cavitator was investigated numerically using the mixture multiphase flow model. It is verified that the forces of pitching, yawing, drag and lift, as well as the supercavity size of the underwater vehicle can be effectively regulated through the movements of the control element of the variable-lateral-force cavitator in the radial and circumferential directions. In addition, if the control element on either side protrudes to a height of 5% of the diameter of the front cavitator, an amount of forces of pitching and yawing equivalent to 30% of the drag force will be produced, and the supercavity section appears concave inwards simultaneously. It is also found that both the drag force and lift force of the variable-lateral-force cavitator decline as the angle of attack increases.

关键词： supercavitating flow cavitator drag force lateral forces numerical investigation