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Establishment and verification of theoretical model for underwater light-sheet Scheimpflug LiDAR system

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Science China Technological Sciences 2025年第1期 54-61页

作者： fei FENG Guojun WU Bo LIU Xu ZHAO Yafeng WU Jinghan XU Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences

The Scheimpflug imaging in the air can increase the depth-of-view and has been well studied with an accurate Scheimpflug imaging model. However, there is no corresponding underwater light-sheet Scheimpflug(ULSS) imaging *** a result, imaging accuracy cannot be ensured in the design phase, which mainly relies on the post-calibration. In this paper,the ULSS imaging model is firstly established, which gives the relationship between the pixel number and target distance, as well as that between the target distance and range resolution. A new experimental bracket and an underwater Scheimflug imaging lens were designed and developed. Based on this new device, several experiments were carried out in a pool to study the range resolution of this ULSS LiDAR, by which the correctness of the imaging model was verified. It also shows that the newly designed ULSS LiDAR can achieve a millimeter-level resolution within 8 m.

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Neuroprotection mediated by natural products and their chemical derivatives

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Neural Regeneration Research 2020年第11期15卷 2008-2015页

作者： fei fei Ning Su Xia Li Zhou fei Department of Ophthalmology Xijing Hospitalthe Fourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Radiation Oncology Xijing Hospitalthe Fourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Neurosurgery Xijing Hospitalthe Fourth Military Medical UniversityXi’anShaanxi ProvinceChina

Neuronal injuries can lead to various diseases such as neurodegenerative diseases,stroke,trauma,ischemia and,more specifically,glaucoma and optic *** cellular mechanisms that regulate neuronal death include calcium influx and calcium overload,excitatory amino acid release,oxidative stress,inflammation and microglial *** attention has been paid to the effective prevention and treatment of neuroprotective drugs by natural *** review summarizes the neuroprotective aspects of natural products,extracted from Panax ginseng,Camellia sinensis,soy and some other plants,and some of their chemical *** antioxidative and anti-inflammatory action and their inhibition of apoptosis and microglial activation are *** will provide new directions for the development of novel drugs and strategies to treat neurodegenerative diseases.

关键词： antioxidant effect brain injuries Camellia sinensis chemical derivatives curcumin genistein natural products neurodegenerative diseases neuroprotection Panax

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基于边缘引导与特征融合的分阶段图像去模糊

光电子·激光 2025年第1期36卷 17-26页

作者：陈清江邵菲王炫钧西安建筑科技大学理学院

针对现有方法去模糊后图像缺乏足够清晰边缘的问题，提出了一种基于边缘引导与特征融合的分阶段图像去模糊方法，分两个阶段逐步去除模糊。首先，第一阶段应用含双交叉集成注意力模块(dual cross integrated attention module, DCIAM)... 详细信息

针对现有方法去模糊后图像缺乏足够清晰边缘的问题，提出了一种基于边缘引导与特征融合的分阶段图像去模糊方法，分两个阶段逐步去除模糊。首先，第一阶段应用含双交叉集成注意力模块(dual cross integrated attention module, DCIAM)的编解码网络学习不同尺度下图像的内容特征，初步去除模糊信息。然后，构建边缘分支网络(edge branch network, EBN)提取图像边缘特征。再次，设计了边缘引导去模糊模块(edge-guided deblurring module, EGDM)以耦合不同分辨率下图像的内容与边缘特征。最后，第二阶段通过级联的残差块和DCIAM进一步去除图像模糊，并通过引入自校准注意融合模块(self-calibrating attention fusion module, SCAFM)增强特征表达效果。实验结果表明：所提方法去模糊后图像的峰值信噪比和结构相似度均值分别达到32.78 dB和0.964,均优于其他对比方法。所提方法可以显著提高去模糊性能且去模糊后图像边缘结构更加完整。

关键词：图像去模糊边缘引导特征融合多尺度框架注意力机制

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基于江苏资源特点的绿色农路建设研究

交通企业管理 2025年第1期40卷 69-71页

作者：顾腾飞苏交科集团股份有限公司

绿色农路建设是践行习近平生态文明思想、深化绿色发展理念、助力美丽中国建设的必然要求,也是支撑交通强国建设、实现行业转型升级的关键举措,需要高度重视农村公路生态保护与修复,不断提高农村公路发展与生态环境的友好程度。目前,绿... 详细信息

绿色农路建设是践行习近平生态文明思想、深化绿色发展理念、助力美丽中国建设的必然要求,也是支撑交通强国建设、实现行业转型升级的关键举措,需要高度重视农村公路生态保护与修复,不断提高农村公路发展与生态环境的友好程度。目前,绿色农路建设尚处于探索阶段,缺乏科学的建设标准规范.

关键词：农村公路绿色农路生态环保节能减排全寿命周期

Orienting the future of bio-macromolecular electron microscopy

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Chinese Physics B 2018年第6期27卷 13-22页

作者： fei Sun Center for Biological Imaging Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Center for Excellent National Laboratory of B iomacromolecule Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China School of Life Science University of Chinese Academy of Sciences Beijing 101407 China

With 40 years of development, bio-macromolecule cryo-electron microscopy（cryo-EM） has completed its revolution in terms of resolution and currently plays a highly important role in structural biology study. According to different specimen states, cryo-EM involves three specific techniques： single-particle analysis（SPA）, electron tomography and subtomogram averaging, and electron diffraction. None of these three techniques have realized their full potential for solving the structures of bio-macromolecules and therefore need additional development. In this review, the current existing bottlenecks of cryo-EM SPA are discussed with theoretical analysis, which include the air–water interface during specimen cryo-vitrification, bio-macromolecular conformational heterogeneity, focus gradient within thick specimens, and electron radiation damage. Furthermore, potential solutions of these bottlenecks worthy of further investigation are proposed and discussed.

关键词： cryo-electron microscopy air-water interface conformational heterogeneity focus gradient radi- ation damage

On a tilted Liouville-master equation of open quantum systems

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Communications in Theoretical Physics 2021年第9期73卷 129-135页

作者： fei Liu School of Physics Beihang UniversityBeijing 100191China

A tilted Liouville-master equation in Hilbert space is presented for Markovian open quantum *** demonstrate that it is the unraveling of the tilted quantum master *** latter is widely used in the analysis and calculat... 详细信息

关键词： quantum stochastic thermodynamic tilted quantum master equation quantum trajectories Feynman-Kac formula stochastic heat Liouville-master equation

Gaussianization of peculiar velocities and bulk flow measurement

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Research in Astronomy and Astrophysics 2021年第10期21卷 5-16页

作者： fei Qin Korea Astronomy and Space Science Institute Yuseong-guDaedeok-daero 776Daejeon 34055Korea

The line-of-sight peculiar velocities are good indicators of the gravitational fluctuation of the density *** have been developed to extract cosmological information from the peculiar velocities in order to test cosmological *** techniques include measuring cosmic flow,measuring two-point correlation and power spectrum of the peculiar velocity fields,and reconstructing the density field using peculiar ***,some measurements from these techniques are biased due to the nonGaussianity of the estimated peculiar ***,we rely on the 2MTF survey to explore a power transform that can Gaussianize the estimated peculiar *** find a tight linear relation between the transformation parameters and the measurement errors of log-distance *** show an example for the implementation of Gaussianized peculiar velocities in cosmology,we develop a bulk flow estimator and estimate bulk flow from the Gaussianized peculiar *** use 2MTF mocks to test the algorithm,and we find the algorithm yields unbiased *** also find this technique gives smaller measurement errors compared to other *** Galactic coordinates,at the depth of 30 h^(-1)Mpc,we measure a bulk flow of 332±27 km s^(-1) in the direction(l,b)=(293°±5°,13°±4°).The measurement is consistent with theΛCDM prediction.

关键词： cosmology:large-scale structure of universe

Modified micro-mechanics based multiscale model for progressive failure prediction of 2D twill woven composites

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Chinese Journal of Aeronautics 2020年第7期33卷 2070-2087页

作者： Meng WANG Peiwei ZHANG Qingguo fei fei GUO Institute of Aerospace Machinery and Dynamics Southeast UniversityNanjing 211189China Department of Engineering Mechanics Southeast UniversityNanjing 211189China

To consider fiber random distribution at the microscale for the multiscale model based on the micro-mechanics failure(MMF)theory,clustering method is used for the extraction of amplification *** the clustering method is a kind of unsupervised machine learning method,the elements with similar mechanical behavior under external loading can be included in a cluster automatically at the *** this modification,the fiber random distribution model can be used for multiscale damage analysis in the framework of MMF *** validate the modified multiscale analysis method,progressive damage analysis of a kind of 2D twill woven composites is conducted based on different microscale *** stress values for microscale models with fiber hexagonal and random distribution patterns are compared *** higher stress concentration is generated in the fiber random distribution model due to the smaller inter-fiber distance especially under longitudinal shear *** obtained cluster distribution results exhibit the characters of the stress distribution in the two microscale ***,tensile and compressive responses of the 2D twill woven composite are predicted with the modified multiscale analysis method and accuracy of the method is verified through comparison with published experimental *** the simulation results,it can be found that the matrix damage initiation from the model based on the fiber random distribution model is premature compared with that from the model based on the fiber hexagonal distribution ***,under tensile loading,the damage all initiates from the fill tows and propagates to the wrap ***,under compressive loading,the matrix damage initiates from the wrap tows in the model based on the fiber random distribution model.

关键词： 2D twill woven composites Clustering analysis Fiber distribution patterns Micro-mechanics failure theory Multiscale damage model

Strain-Rate-Dependent In-Plane Compressive Properties of 3D Fine Weave Pierced C/C Composite:Failure Mechanism and Constitutive Model

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Acta Mechanica Solida Sinica 2022年第1期35卷 63-78页

作者： fei Guo Qingguo fei Yanbin LiL Nikhil Gupta Jiangsu Engineering Research Center of Aerospace Machinery Southeast UniversityNanjing 211189China Department of Engineering Mechanics Southeast UniversityNanjing 211189China School of Mechanical Engineering Southeast UniversityNanjing 211189China Composite Materials and Mechanics Laboratory Department of Mechanical and Aerospace EngineeringTandon School of EngineeringNew York UniversityBrooklynNY 11201USA

In-plane compression experiments are performed on 3D fine weave pierced C/C composite at a wide strain rate range of 0.0001/s-1000/*** in-plane compressive failure mechanism of the composite at quasi-static and high strain rates is analyzed by a scanning electron *** results show that the in-plane compressive modulus,maximum stress and the corresponding strain increase with increasing strain *** quasi-static in-plane compressive failure mode of the 3D fine weave pierced C/C composite is characterized by the shear failure at the angle of 45°and the local buckling of the^direction fiber *** comparison,the high strain rate in-plane compression failure mode of the composite is characterized by the compressive fracture of the interlaminar matrix and the progressive compression failure of the a>direction fiber bundles.A strain-rate-dependent in-plane compressive constitutive model is proposed to predict the dynamic in-plane compressive response of the *** proposed constitutive model is verified by experimental data.

关键词： C/C composite Compression Failure mechanism Constitutive model