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Tunnel crack detection method based on Crack-Aware Vision Transformer

Journal of Traffic and Transportation engineering(English Edition) 2025年

作者： Xuanran Liu Liqiang Zhu Yaodong Wang Zujun Yu School of Mechanical， Electronic and Control Engineering， Beijing Jiaotong University Frontiers Science Center for Smart High-speed Railway System， Beijing Jiaotong University

The occurrence of cracks as a common surface defect in tunnel linings is influenced by a combination of internal and external factors. In recent years， computer vision methods have been widely applied in the field of crack detection. Deep learning has the capability to handle large-scale crack image data and automatically extract crack features. However， owing to numerous difficulties， including low-quality images， intricate cracks， and complex background environments， it is challenging to solve these tricky issues in tunnel crack detection. Therefore， this paper proposes a tunnel lining crack detection model based on Crack-aware Vision Transformer (CAViT)， which includes a perceptual vision transformer backbone network and an improved decoding network. The vision Transformer model has a stronger contextual modeling ability and is suitable for the task of extracting features from tunnel cracks with long， fine， and irregular characteristics. Due to the limitations of the attention mechanism based on a fixed window in modeling long-range relationships， we propose Crack-aware self-attention with the ability to increase the attention to relevant features and extract long-distance feature dependencies. This attention mechanism focuses on the crack area by learning the transformation parameters of the sampled window and reference points from the prediction module， and the position bias generated by the transformation compensate in the position encoding. Subsequently， we employ recurrent convolution layers to enhance the fusion network's ability to integrate contextual information. Our proposed CAViT is evaluated on the Crack500 dataset and a self-made tunnel crack dataset. Experimental results show that our network achieves the highest scores in terms of crack intersection-over-union (IoU) and accuracy (Acc) compared to other transformer models in both datasets. These results demonstrate the suitability of our CAViT for pavement crack and tunnel crack detection tasks， sho

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Water-Driven Malleable,Weldable and Eco-Friendly Recyclable Carbon Fiber Reinforced Dynamic Composites

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Chinese Journal of Chemistry 2024年第5期42卷 516-522页

作者： Ping Yu Qirui Huang Yi Wang Wan Peng Zichen Jia Haiyue Wang Juanjuan Ma Chunyu Wang Xuzhou Yan School of Environmental and Chemical Engineering Jiangsu Key Laboratory of Function Control Technology for Advanced MaterialsJiangsu Ocean UniversityLianyungangJiangsu222005 China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai200240 China

Traditional carbon fiber-reinforced polymers based on thermoset matrix have been extensively used in the fields of wind turbine blades,automotive sector,and aerospace,among many ***,there is still a major challenge of recycling those polymers due to the high cost and adverse impacts on the *** this work,we apply a polyimine network as matrix,which possess considerable tensile and thermal properties,to prepare the carbon fiber reinforced polyimine materials with trifluoromethyl diphenoxybenzene units(CFRFP)using a prepreg-based compression molding *** CFRFP can be reshaped or reprocessed by heat or with water rapidly,and exhibited multifunction,including welding,chemical recycling,*** unique findings gained from our study will facilitate the manufacturing capability and enrich the types of fiber-reinforced composites.

关键词： Dynamic chemistry Green chemistry Fiber-reinforced composites Fluoropolyimine Welding Reshaping Recycling Renewable resources

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Growth,optical dispersion and magnetic behavior of Dy^(3+) doped yttrium iron garnet crystals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating Fang Hui Shen Yudie Ma Shijie Liao Shuang Xia Tian Tian Ding Zhou Yunfeng Ma Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control Materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3)Fe_(5)O_(12)(YIG)crystals are highly desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality single ***^(3+)doping is expected to improve the optical and magneto-optical prope ***,high quality Dy:YIG crystals and the adjustment of Dy^(3+)on the structure and optical behavior of YIG crystal remain unclear,impeding its practical ***,a series of Y_(3-x)Dy_(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3)solid solution crystals was grown by the flux-Bridgman method and single crystals up to 25 mm were *** the introduction of Dy^(3+),lattice parameters are gradually enlarged from 1.2379 nm(YIG)to 1.2420 nm(DyIG).Typical Dy^(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for YIG crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for DyIG *** optical bandgaps remain almost unchanged for Dy:YIG *** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3+)content,the saturation magnetization(Ms)decreases significantly from 23.62 emu/g(YIG)to 5.33 emu/g(DyIG).Small coercive field is persisted for this system,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical crystals,which is beneficial to the design of high-performance garnet crystals for the application of optical switching and non-reciprocal related devices.

关键词： Magneto-optical crystal Yttrium iron garnet Dy^(3+)doping Crystal growth Optical dispersion Rare earths

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Speciation and biogeochemical behavior of perfluoroalkyl acids in soils and their environmental implications:A review

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Eco-Environment & Health 2024年第4期3卷 505-515页

作者： Chao Guo Shiwen Hu Pengfei Cheng Kuan Cheng Yang Yang Guojun Chen Qi Wang Ying Wang Tongxu Liu National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agroenvironmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China

Perfluoroalkyl acids(PFAAs)are emerging organic pollutants that have attracted significant attention in the fields of environmental chemistry and *** PFAAs are pervasive in soils and sediments,there is a paucity of research regarding their environmental forms and driving *** review provides an overview of the classification and biotoxicity of per-and polyfluoroalkyl substances(PFAS),organic pollutant forms,PFAS extraction and analytical methods,the prediction of PFAS distribution in soils,and current PFAS remediation *** predominant PFAA forms have been proposed in soils:(i)aqueous-extracted PFAAs,(ii)organic-solvent extracted PFAAs,(ii)embedded or sequestered PFAAs,and(iv)covalently bound ***,it suggests suitable extraction methods and predictive models for different PFAA forms,which are instrumental in the research on PFAA speciation and prediction in ***,it was proposed that elemental cycling and microbial activity may affect the speciation of ***,the categorization of PFAA forms facilitated the analysis of pollution *** the interplay between PFAA speciation,element cycling,and bacterial activity during soil remediation is essential for understanding remediation mechanisms and assessing the long-term stability of remediation *** studies should expand the investigation of varying PFAA forms in different media,consider the potential binding forms of PFAAs to minerals,organic matter,and microbes,and evaluate the possible mechanisms of PFAA speciation variation.

关键词： Perfluoroalkyl acids Per-and polyfluoroalkyl substances Extraction and analysis methods Contamination remediation Speciation

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Valley-selective manipulation of moiréexcitons through optical Stark effect

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Chinese Physics B 2025年第1期34卷 14-18页

作者： Chenran Xu Jichen Zhou Zhexu Shan Wenjian Su Kenji Watanabe Takashi Taniguchi Dawei Wang Yanhao Tang School of Physics Zhejiang UniversityHangzhou 310027China Zhejiang Key Laboratory of Micro-Nano Quantum Chips and Quantum Control Zhejiang UniversityHangzhou 310027China Research Center for Electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan

Semiconductor moirésuperlattices provide great platforms for exploring exotic collective *** Stark effect,a shift of the electronic transition in the presence of a light field,provides an ultrafast and coherent method of manipulating matter states,which,however,has not been demonstrated in moiré***,we report the valleyselective optical Stark effect of moiréexcitons in the WSe_(2)/WS_(2)superlattice by using transient reflection *** valley-selective energy shifts up to 7.8 meV have been observed for moiréexcitons,corresponding to pseudomagnetic fields as large as 34 *** results provide a route to coherently manipulate exotic states in moirésuperlattices.

关键词： optical Stark effect moir´e exciton transient reflection spectroscopy

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research on Active Disturbance Rejection control Technology of Two-wheel Self-balancing Robot 5

Research on Active Disturbance Rejection Control Technology ...

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5th International Conference on Electrical engineering and control Technologies, CEECT 2023

作者： Liu, Wenyang Zhang, Bo Guo, Shuai Shi, Junbiao Ji, Mingming Zheng, Sha Control Engineering Aerospace Science and Beijing Space Power Conversion Research Center Dept.Beijing Spacecraft China Technology Corporation Beijing China

ISBN: (纸本)9798350342253

The two-wheel self-balancing robot has the advantages of small size and flexible operation, but it is an inverted pendulum system with electromechanical integration, which has the characteristics of nonlinearity, strong coupling, and many random disturbances. The overshoot returns to the equilibrium point. In this paper, an active disturbance rejection control method combining a PD controller and linear extended state observer is studied, and the simulation analysis and verification experiment of this control system are carried out. The experimental results show that the control system can estimate the external disturbance, so that the self-balancing robot can quickly track to the equilibrium position without overshooting, and has strong robustness and anti-interference ability. © 2023 IEEE.

关键词： Wheels

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Synergistically enhancing nitrate reduction into N_(2)in water by N-doped Pd-Cu biochar bimetallic single-atom electrocatalysis

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Biochar 2024年第1期6卷 114-131页

作者： Lihao Zhang Yuqing Wu Zongqiang Zhu Yinian Zhu Yi Dong Meina Liang Huan Deng College of Environmental Science and Engineering Guilin University of TechnologyGuilin 541006People’s Republic of China. Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology Guilin 541006People’s Republic of China. Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area Guilin University of TechnologyGuilin 541006People’s Republic of China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100035People’s Republic of China.

Noble metal materials have been identified as high efficiency catalysts for electrocatalytic reduction of nitrate,and the synthesis and manufacture of high catalytic activity and environmentally friendly catalysts of activating hydrogen for water purification applications is extremely *** this work,the Pd-Cu single-atom catalysts(Pd-Cu-N-BC)were first prepared by direct growth of Pd-Cu single-atom on bamboo biochar by regulating the concentration of precursors and doping method,and then enhanced electrocatalytic reduction nitrate performance and N2 *** results showed that Pd-Cu-N-BC displayed excellent catalytic activity and reusability in electrocatalytic reduction nitrate with a low potential of 0.47 V ***(@10 mA cm−2).The maximum nitrate removal efficiency and N2 generation could reach about 100%and 72.32%within 180 min,*** density functional theory(DFT)calculations confirmed that Cu atoms could catalyze the electrochemical reduction of nitrate to nitrite,and Pd atoms anchored in the nitrogen-doped biochar(N-BC)lattice could catalyze electrochemical reduction of nitrite to N2 involving the formation of hydrogen radical(H*).The characterization results of XANES showed that electronic synergistic effect between Pd and Cu single atoms significantly promotes the N2 production through hydrogenation while inhibiting the generation of byproducts,leading to significantly enhanced electrocatalytic reduction of nitrate to ***,Pd-Cu-N-BC was designed as a 3D particle electrode for enhanced electrocatalytic reduction of nitrate,exhibiting excellent stability and reusability,which could be considered as a suitable candidate for applications in the remediation of nitrate contamination.

关键词： Bamboo biochar Single atom catalyst Electrocatalytic denitration Hydrogen evolution reaction Density functional theory

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A Multi-Layer Frequency Selective Surface with Broad Bandpass and High Selectivity

A Multi-Layer Frequency Selective Surface with Broad Bandpas...

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2024 IEEE International Conference on Computational Electromagnetics, ICCEM 2024

作者： Gao, Ruicheng Wen, Shuai Mao, Yongyan Bi, Lige School of Electronic Engineering Xidian University Xian China Science and Technology On Electromechanical Dynamic Control Laboratory China Electronic Engineering Research Institute Xian China

ISBN: (纸本)9798350383317

A novel broadband bandpass Frequency Selective Surface (FSS) is designed with the intention of surpassing the performance of previous designs. Through the utilization of cascading multilayers of capacitive patches and inductive grids, this design achieves our goal of wide bandwidth as well as high selectivity, while maintaining an acceptable thickness. The stimulated results exhibit a broad passband width, ranging from 12.5 GHz to 18.2 GHz, as well as steep out-of-band attenuation with a transitional zone of less than 1 GHz. © 2024 IEEE.

关键词： Frequency selective surfaces

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On a Structural Approach to the Complex Systems Conceptual Modeling 4

On a Structural Approach to the Complex Systems Conceptual M...

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4th International Conference on control, Artificial Intelligence, Robotics and Optimization, ICCAIRO 2023

作者： Brodsky, Yury I. Federal Research Center 'Computer Science and Control' of the Russian Academy of Sciences Simulation Systems and Operation Research Department Moscow Russia

ISBN: (纸本)9798350300918

Conceptual modeling is gaining an essential role in designing large-scale systems, especially as the complexity of the latter increases. The design tool for such systems is the development of ontologies for their subject areas. A problem arises: in our activity, we consider more complex subject areas, and the complexity of ontologies is growing. Is there a limit to this complexity? The design of large-scale systems is already suffocating with complexity - it is difficult to describe the components of the domain, their synthesis is complicated, and even more difficult is the software implementation of the model within the framework of an imperative, object-oriented approach. Debugging the created software system is extremely difficult. The structural theory offers a unified way to describe the subject areas of a broad class of large-scale systems, realizing in this description the principle of 'One in everything and all in One.' Based on this, an end-to-end technology of reporting, synthesis, and software implementation of models of complex, large-scale systems, which is close to CAD methods, is being built. In implementing a software system, it is possible to remain within the framework of declarative programming, avoiding imperative programming, which significantly simplifies its debugging. © 2023 IEEE.

关键词： Large scale systems

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Decentralized Game-based Auction Algorithm for Scheduling Robotic Chargers to Service EVs with Uncertain Demands

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年 1-14页

作者： Fang, Qiuyang Zhang, Jianlei Wang, Chen Xie, Guangming Zhang, Chunyan Department of Automation College of Computer and Control Engineering Nankai University Tianjin China National Engineering Research Center of Software Engineering Peking University Beijing China State Key Laboratory for Turbulence and Complex Systems Intelligent Biomimetic Design Lab College of Engineering Peking University Beijing China

In this study, we introduce a novel auction-based algorithm modeled as a decentralized coalition formation game, designed for the complex requirements of large-scale multi-robot task allocation under uncertain demand. This context is particularly illustrative in scenarios where robots are tasked to charge electric vehicles. The algorithm begins by partitioning a composite task sequence into distinct subsets based on spatial similarity principles. Subsequently, we employ a coalition formation game paradigm to coordinate the assembly of robots into cooperative coalitions focused on these distinct subsets. To mitigate the impact of unpredictable task demands on allocations, our approach utilizes the conditional value-at-risk to assess the risk associated with task execution, along with computing the potential revenue of the coalition with an emphasis on risk-related outcomes. Additionally, integrating consensus auctions into the coalition formation framework allows our approach to accommodate assignments for individual robot-task pairings, thus preserving the stability of individual robotic decision autonomy within the coalition structure and assignment distribution. Simulative analyses on a prototypical parking facility layout confirm that our algorithm achieves Nash equilibrium within the coalition structure in polynomial time and demonstrates significant scalability. Compared to competing algorithms, our proposal exhibits superior performance in resilience, task execution efficiency, and reduced overall task completion times. The results demonstrate that our approach is an effective strategy for solving the scheduling challenges encountered by multi-robot systems operating in complex environments. IEEE

关键词： Polynomial approximation

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