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改进U2-Net的激光条纹中心线高精度提取

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光电子·激光 2025年第1期36卷 61-68页

作者：陈新禹孙晓雨孙延鹏沈阳航空航天大学人工智能学院沈阳航空航天大学电子信息工程学院

针对复杂环境下激光条纹中心线提取算法稳定性差、精度低等问题，提出一种基于改进U2-Net的中心线提取新方法。首先，在U2-Net网络中加入TSA（transformer-self-attention）、TCA（transformer-cross-attention）模块以提高模型的特征... 详细信息

针对复杂环境下激光条纹中心线提取算法稳定性差、精度低等问题，提出一种基于改进U2-Net的中心线提取新方法。首先，在U2-Net网络中加入TSA（transformer-self-attention）、TCA（transformer-cross-attention）模块以提高模型的特征提取能力，实现精准像素级分割，有效去除图像中的噪声、毛刺，为后续中心线提取提供高质量的图像源；其次，根据使用场景特点，对传统Steger方法进行改进，完成激光条纹中心线高精度提取；最后，采用信度评价机制对光条中心点进行精度分析。实验结果表明，本文提出的改进U2-Net相较其他主流语义分割网络具有更高的提取精度、更好的抗噪声性能，在此基础上提取的像素中心点的信度值更高，达到传统Steger算法的1.9倍，满足高精度工业测量的需求。

关键词：线结构光语义分割光条中心提取信度评价

Nanoparticles for the treatment of spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1665-1680页

作者： Qiwei Yang Di Lu Jiuping Wu Fuming Liang Huayi Wang Junjie Yang Ganggang Zhang Chen Wang Yanlian Yang Ling Zhu xinzhi sun Department of Orthopedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Neurosurgery The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

关键词： antioxidants axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases neuroprotection spinal cord injury stem cells

A Deep Learning Approach for Fault Diagnosis of Induction Motors in Manufacturing

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1347-1356页

作者： Si-Yu Shao Wen-Jun sun Ru-Qiang Yan Peng Wang Robert x Gao School of Instrument Science and Engineering Southeast University Department of Mechanical and Aerospace Engineering Case Western Reserve University

Extracting features from original signals is a key procedure for traditional fault diagnosis of induction motors, as it directly influences the performance of fault recognition. However, high quality features need expert knowledge and human intervention. In this paper, a deep learning approach based on deep belief networks （DBN） is developed to learn features from frequency distribution of vibration signals with the purpose of characterizing work- ing status of induction motors. It combines feature extraction procedure with classification task together to achieve automated and intelligent fault diagnosis. The DBN model is built by stacking multiple-units of restricted Boltzmann machine （RBM）, and is trained using layer-by- layer pre-training algorithm. Compared with traditional diagnostic approaches where feature extraction is needed, the presented approach has the ability of learning hierar- chical representations, which are suitable for fault classi- fication, directly from frequency distribution of the measurement data. The structure of the DBN model is investigated as the scale and depth of the DBN architecture directly affect its classification performance. Experimental study conducted on a machine fault simulator verifies the effectiveness of the deep learning approach for fault diagnosis of induction motors. This research proposes an intelligent diagnosis method for induction motor which utilizes deep learning model to automatically learn features from sensor data and realize working status recognition.

关键词： Fault diagnosis Deep learning Deep beliefnetwork. RBM Classification

Effect of electric boundary conditions on crack propagation in ferroelectric ceramics

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Acta Mechanica Sinica 2014年第2期30卷 153-160页

作者： F.-x. Li Y.sun R.K.N.D.Rajapakse State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking University Faculty of Applied Sciences Simon Fraser University

In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga Njiwa et al.（Eng. Fract. Mech., 2006）.

关键词： Ferroelectric ceramics Crack propagation En-ergy release rate Electric boundary conditions Domain switching

EFFECTS OF THERMAL CYCLE ON MECHANICAL PROPERTIES AND FRACTOGRAPHY IN HAZ OF HQ130 STEEL

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 274-278页

作者： B. Liu J.x.Qu W.J.sun Department of Mechanical Engineering Changsha University Changsha 410003 China Department of Materials Sci. & Eng. China Univ. of Mining and Technology Beijing 100083 ChinaDepartment of Materials Sci. & Eng. China Univ. of Mining and Technology Beijing 100083 ChinaDepartment of Materials Sci. & Eng. China Univ. of Mining and Technology Beijing 100083 China

The effect of different peak temperature T_P) and cooling time (t_(8/5)) on hardness,impact toughness and fracture morphology in the heat--affected zone (HAZ) of HQ130steel was studied by using welding thermo--simulation test. Experimental results showthat the impact toughness and hardness decrease with the decrease of T_P or increase oft_(8/5) under the condition of a single thermal cycle. There is a brittle zone in the vicinityof T_P=800℃, where the impact toughness is considerebly low. There is softened zonein vicinity of T_P=700℃, Where the harkness decreases but the toughness increases. Inthe practical application of multi--layer and multi--pass welding, the welding heat inputshould be strictly limited (t_(8/5)≤20s) so as to reduce the softness and brittleness in theHAZ of HQ130 steel.

关键词： high strength steel welding thermal cycle heat-affected zone impact toughness

Effects of rejuvenation heat treatment on microstructure and creep property of a Ni-based single crystal superalloy

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Journal of Materials Science & Technology 2021年第1期60卷 206-215页

作者： K.J.Tan x.G.Wang J.J.Liang J.Meng Y.Z.Zhou x.F.sun Superalloys Division Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Both surface and internal microstructures of a second-generation Ni-based single crystal(Sx) superalloy were studied after creep and rejuvenation heat treatment(RHT).It is indicated that the microstructures,such as the dislocation network,the γ phase and the γ' phase,can be recovered to those after the standard heat treatment(SHT).It is found that RHT affected zone(RAZ) formed at the surface is composed of theγ'-free layer,the transition layer and the recrystallization(Rx),which are less than 20 μm in depth *** depth of the RAZ doesn't affect the properties of the *** morphology of γ' phase at the RAZ is related to the composition of the *** average creep life after RHT is close to the average life after *** is concluded that RHT could effectively repair Sx parts and increase the total life of the sample after a damage by creep.

关键词： Superalloys Rejuvenation heat treatment Microstructure Creep property

Bulk nanocrystalline W-Ti alloys with exceptional mechanical properties and thermal stability

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Journal of Materials Science & Technology 2022年第19期114卷 16-28页

作者： H.x.xue x.C.Cai B.R.sun x.Shen C.C.Du x.J.Wang T.T.Yang S.W.xin T.D.Shen Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China CSSC 723rd Research Institute China State Shipbuilding Corporation LimitedYangzhou 225000China

Nanocrystalline(NC)W metals and alloys often exhibit higher radiation tolerance and strength than their coarse-grained ***,their thermal stability is low,making it difficult to achieve bulk NC W metals and alloys by consolidation using conventional techniques such as pressure-less sintering,hot-explosive-compaction sintering,and spark plasma *** we report the synthesis and mechanical properties of bulk NC W_(100-x)Ti_(x)(x=10 at.%-30 at.%)alloys prepared by consolidating mechanically alloyed NC powders under a high-temperature/high-pressure *** 20 at.%-30 at.%Ti largely improves the sinterability of NC W-Ti alloy *** room-temperature microhardness and compressive yield strength of consolidated bulk NC W_(80)Ti_(20) alloy are∼16.9 and 6.0 GPa,respectively,which are mainly caused by grain boundary strengthening and significantly higher than those of previously reported W and W *** ultimate compressive strength of bulk NC W_(80)Ti_(20) measured between 900 and 1100°C deceases with increasing *** behavior can be explained by the activation of Rachinger grain boundary *** grain growth is observed in bulk NC W_(80)Ti_(20) after compression at 1000°*** calculation suggests that it is the segregation of Ti at grain boundaries that decreases the specific grain boundary free energy and makes the NC W_(80)Ti_(20) alloy thermodynamically stable.

关键词： Nanocrystalline W-Ti alloys Segregation Grain boundary energy Strength Hardness

MICROSTRUCTURES AND OxIDATION RESISTANCE OF Fe_3Al WELD OVERLAY

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 253-256页

作者： x.G. Mi x.Q. Yu, Y.S. sun and J.R. sun Department of Materials Science and Engineering, Southeast University, Nanjing 210096, China Dept. of Mat. Sci. Southeast Univ. Nanjing 210096 China

Using the Fe3Al electrode through manual arc surfacing (MAS), Fe3Al coatings were deposited on the stainless steel substrate. The microstructures, hardness and oxidation resistance of the weld overlay were investigated. The results show that crack-free overlays can be obtained when pre-heating the substrate at 500°C and postweld heat treatment at 700°C are used. Elements of Al, Cr and Ni, etc. transfer between the substrate and the overlay, but this does not influence the microhardness of the substrate and the Fe3Al overlay. Oxidation tests show that the Fe3Al overlay has excellent oxidation resistance in comparison with the stainless steel substrate at 800°C and 900°C.

关键词： Aluminum Intermetallics Iron Microstructure Oxidation resistance

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岩浆岩中磷灰石的地球化学特征及应用

岩石学报 2025年第1期41卷 321-338页

作者：李子木令狐苗苗孙金凤孙之晗周宝全杨进辉中国科学院大学地球与行星科学学院北京100049 中国科学院大学北京燕山地球关键带国家野外科学观测研究站北京101408 中国科学院地质与地球物理研究所岩石圈演化与环境演变全国重点实验室北京100029

不同类型的岩浆岩可能来源于不同源区,经历复杂的岩浆演化过程,导致岩浆成分、温度和压力等条件发生变化。磷灰石在岩浆岩中广泛发育,可以形成于不同的岩浆环境。作为富含多种地球化学指示元素(如稀土元素、锶、锰及多种挥发分),并且对... 详细信息

不同类型的岩浆岩可能来源于不同源区,经历复杂的岩浆演化过程,导致岩浆成分、温度和压力等条件发生变化。磷灰石在岩浆岩中广泛发育,可以形成于不同的岩浆环境。作为富含多种地球化学指示元素(如稀土元素、锶、锰及多种挥发分),并且对寄主岩浆环境的变化十分敏感的副矿物,近年来被广泛应用于岩浆岩和矿床成因等研究中。了解不同类型岩石中磷灰石的矿物学和地球化学特征,是深入开展相关研究的基础。本文对GEOROC数据库及其他文献报道的岩浆岩中磷灰石稀土元素数据进行了汇总整理和归纳分析,获得了不同类型岩石中磷灰石的矿物学和稀土元素组成特征。结合多元统计分析方法,深入分析不同类型岩浆岩和花岗岩中磷灰石的稀土元素变化规律。计算结果显示,不同类型岩石中磷灰石的La元素、Eu/Eu*和Yb含量之间存在明显差异,推断综合利用La含量与(Eu/Eu^(*))/Yb值特征可以有效区分形成于不同岩浆岩的磷灰石。本文的研究表明,磷灰石在示踪岩浆源区和岩石成因方面具有独特优势,综合运用磷灰石产状、共生矿物组合、微量元素及同位素组成等分析可以为岩浆岩成因研究提供全面信息。

关键词：岩浆岩花岗岩磷灰石地球化学稀土元素岩石成因