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Deep feature extraction and motion representation for satellite video scene classification

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Science China(Information Sciences) 2020年第4期63卷 97-111页

作者： Yanfeng GU Huan liU Tengfei WANG shengyang li Guoming GAO School of Electronics and Information Engineering Harbin Institute of Technology Technology and Engineering Center for Space Utilization Chinese Academy of Sciences The Key Laboratory of Space Utilization Chinese Academy of Sciences

Satellite video scene classification(SVSC) is an advanced topic in the remote sensing field, which refers to determine the video scene categories from satellite videos. SVSC is an important and fundamental step for satellite video analysis and understanding, which provides priors for the presence of objects and dynamic events. In this paper, a two-stage framework is proposed to extract spatial features and motion features for SVSC. More specifically, the first stage is designed to extract spatial features for satellite *** frames are firstly selected based on the blur detection and spatial activity of satellite *** the fine-tuned visual geometry group network(VGG-Net) is transferred to extract spatial features based on spatial content. The second stage is designed to build motion representation for satellite *** motion representation of moving targets in satellite videos is first built by the second temporal principal component of principal component analysis(PCA). Second, features from the first fully connected layer of VGG-Net are used as high-level spatial representation for moving targets. Third, a small network of long and short term memory(LSTM) is further designed for encoding temporal information. Two-stage features respectively characterize spatial and temporal patterns of satellite scenes, which are finally fused for SVSC.A satellite video dataset is built for video scene classification, including 7209 video segments and covering 8 scene categories. These satellite videos are from Jilin-1 satellites and Urthecast. The experimental results show the efficiency of our proposed framework for SVSC.

关键词： satellite videos classification convolutional neural network CNN long and short term memory LSTM motion representation

Quantifying the adsorption and uptake of CuO nanoparticles by wheat root based on chemical extractions

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Journal of Environmental Sciences 2011年第11期23卷 1852-1857页

作者： Dongmei Zhou shengyang Jin lianzhen li Yu Wang Nanyan Weng Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Extensive application of metal nanoparticles is attracting more attention because of their potential environmental *** studies have focused on the uptake of metal nanoparticles （NPs） by plant,but the adsorption of nanoparticles on root surface is often mistakenly regarded as their *** study optimized the methods to distinguish the adsorption and uptake of CuO-NPs on the wheat root by applying different metal competing ions （Na ＋,Mg 2＋,and La 3＋）,surfactant （i.e.,sodium dodecyl benzene sulfonate,SDBS）,or complexing agents like NaOAc and Na 4 EDTA,as well as ultrasonic *** results indicated that some CuO-NPs is strongly adsorbed on the plant root surface,and part of them by mechanical *** ions could not desorb the CuO-NPs from the root surface,while NaOAc and Na 4 EDTA well dissolved the adsorbed *** addition,the uptake and adsorption of CuO-NPs increased with increasing exposure concentrations of CuO-NPs in the range of 5–200 mg/*** amount of CuO-NPs adsorption is always lower than that of their uptake.

关键词： CuO-NPs root surface adsorption uptake

Cloning and characterization of an apolipoprotein C2 promoter in the mouse central nervous system

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Neural Regeneration Research 2013年第2期8卷 156-161页

作者： Zhaoyang li Bing Du shengyang li Xiangchuan Lv Shenglai Zhou Yang Yu Wei Wang Zhihong Zheng Key Laboratory of Transgenetic Animal Research Department of Laboratory Animal China Medical University College of Animal Science & Veterinary Medicine Shenyang Agricultural University

Apolipoprotein C2 is an important member of the apolipoprotein C family, and is a potent activator of lipoprotein lipase. In the central nervous system, apolipoprotein C2 plays an important role in the catabolism of triglyceride-rich lipoproteins. Studies into the exact regulatory mechanism of mouse apolipoprotein C2 expression have not been reported. In this study, seven luciferase expression vectors, which contained potential mouse apolipoprotein C2 gene promoters, were constructed and co-transfected with pRL-TK into HEK293T cells to investigate apolipoprotein C2 promoter activity. Luciferase assays indicated that the apolipoprotein C2 promoter region was mainly located in the ＋104 bp to ＋470 bp region. The activity of the different lengths of apolipoprotein C2 promoter region varied. This staggered negative-positive-negative arrangement indicates the complex regulation of apolipoprotein C2 expression and provides important clues for elucidating the regulatory mechanism of apolipoprotein C2 gene transcription.

关键词： neural regeneration basic research apolipoprotein C2 promoter dual-luciferase reporter assay transcriptional activity regulatory elements grants-supported paper neuroregeneration

Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching

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Chinese Journal of Acoustics 2015年第2期34卷 123-137页

作者： WU Shaowei XIANG Yang li shengyang School of Energy and Power Engineering Wuhan University of Technology Key Laboratory of Marine Power Engineering & Technology Ministry of Communications

Choosing particular solution source and its position have great influence on accu- racy of sound field prediction in distributed source boundary point method. An optimization method for determining the position of particular solution sources is proposed to get high accu- racy prediction result. In this method, tripole is chosen as the particular solution. The upper limit frequency of calculation is predicted by setting 1% volume velocity relative error limit using vibration velocity of structure surface. Then, the optimal position of particular solution sources, in which the relative error of volume velocity is minimum, is determined within the range of upper limit frequency by searching algorithm using volume velocity matching. The transfer matrix between pressure and surface volume velocity is constructed in the optimal position. After that, the sound radiation of structure is calculated by the matrix. The results of numerical simulation show that the calculation error is significantly reduced by the proposed method. When there are vibration velocity measurement errors, the calculation errors can be controlled within 5% by the method.

关键词： Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching

High Initial Reversible Capacity and Long life of Ternary SnO_(2)-Co-carbon Nanocomposite Anodes for lithium-Ion Batteries

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Nano-Micro Letters 2019年第1期11卷 326-338页

作者： Pan Deng Jing Yang shengyang li Tian-E Fan Hong-Hui Wu Yun Mou Hui Huang Qiaobao Zhang Dong-liang Peng Baihua Qu Pen-Tung Sah Institute of Micro-Nano Science and Technology Department of Materials Science and Engineering College of Materials Xiamen University College of Automation and Key Laboratory of Industrial Internet of Things and Networked Control Ministry of Education Chongqing University of Posts and Telecommunications Department of Chemistry University of Nebraska-Lincoln School of Mechanical Science and Engineering Huazhong University of Science and Technology

The two major limitations in the application of SnO_2 for lithium?ion battery(liB) anodes are the large volume variations of SnO_2 during repeated lithiation/delithiation processes and a large irreversible capacity loss during the first cycle, which can lead to a rapid capacity fade and unsatisfactory initial Coulombic e ciency(ICE). To overcome these limitations, we developed composites of ultrafine SnO_2 nanoparticles and in situ formed Co(CoSn) nanocrystals embedded in an N?doped carbon matrix using a Co?based metal–organic framework(ZIF?67). The formed Co additives and structural advantages of the carbon?confined SnO_2/Co nanocomposite e ectively inhibited Sn coarsening in the lithiated SnO_2 and mitigated its structural degradation while facilitating fast electronic transport and facile ionic di usion. As a result, the electrodes demonstrated high ICE (82.2%), outstanding rate capability(～ 800 mAh g^(-1) at a high current density of 5 A g^(-1)), and long?term cycling stability(～ 760 mAh g^(-1) after 400 cycles at a current density of 0.5 A g^(-1)). This study will be helpful in developing high?performance Si(Sn)?based oxide, Sn/Sb?based sulfide, or selenide electrodes for liBs. In addition, some metal organic frameworks similar to ZIF?67 can also be used as composite templates.

关键词： Ultrafine SnO_(2) nanostructures ZIF-67 frameworks Enhanced initial Coulombic efficiency Reversible conversion reaction

N/S co-doped carbon nanosheet bundles as high-capacity anode for potassium-ion battery

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Nano Research 2022年第3期15卷 2040-2046页

作者： Jinhui Cao Jiang Zhong Hanjiao Xu shengyang li Hongli Deng Tao Wang ling Fan Xinghui Wang Lei Wang Jian Zhu Bingan Lu Xidong Duan Hunan Key Laboratory of Two-Dimensional Materials State Key Laboratory for Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China School of Physics and Electronics Hunan UniversityChangsha 410082China College of Physics and Information Engineering Institute of Micro-Nano Devices and Solar CellsFuzhou UniversityFuzhou 350108China

Potassium-ion batteries(PIBs)are of academic and economic significance,but still limited by the lack of highly active electrode materials for de-/intercalation of large-radius K ***,an interconnected nitrogen/sulfur co-doped carbon nanosheep bundle(N/S-CSB)was proposed as the potassium ions storage *** rich co-doping of nitrogen/sulfur of N/S-CNB with three-dimensional hierarchical bundled array structure yields distensible interlayer spaces to buffer the volume expansion during K+insertion/extraction,offers more electrochemical active sites to obtain a high specific capacity,and provides efficient channels for fast ion/electron ***,the N/S-CSB anode achieved high reversible specific capacity of 365 mAh/g obtained at 50 mA/g after 200 cycles with a coulombic efficiency(CE)close to 100%,high rate performance and long cycle ***,the in-situ Raman spectra indicated outstanding reaction kinetics of as-prepared N/S-CSB anode.

关键词： potassium-ion battery anode carbon nanosheet bundles N/S co-doping high capacity long cycle

In situ formation of lithiophilic li_(22)Sn_(5) alloy and high li-ion conductive li_(2)S/li_(2)Se via metal chalcogenide SnSSe for dendrite-free li metal anodes

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Journal of Energy Chemistry 2022年第10期31卷 339-347,I0008页

作者： Yaya Wang Yang Guo Jiang Zhong Meng Wang Lei Wang shengyang li Song Chen Hongli Deng Yong liu Yidi Wu Jian Zhu Bingan Lu State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan Key Laboratory of Two-Dimensional MaterialsEngineering Research Center of Advanced CatalysisMinistry of EducationHunan UniversityChangsha 410082HunanChina School of Energy Science and Engineering Central South UniversityChangsha 410082HunanChina School of Physics and Electronics Hunan UniversityChangsha 410082HunanChina

lithium metal has gained extensive attention as the most ideal candidate for next-generation battery anode owing to the ultrahigh specific capacity and the lowest electrochemical ***,uncontrollable dendrite growth and huge volume variation extremely restrict the future deployment of lithium metal ***,we report metal chalcogenide SnSSe with unique nanoplate stacking structure as a robust substrate for stable li metal *** the initial li plating process,lithiophilic li_(22)Sn_(5) alloy and li_(2)S/li_(2)Se sites are obtained via in-situ electrochemical reaction of li metal and *** functional theory(DFT)calculation demonstrates that the formed li_(2)S/li_(2)Se achieves low li diffusion energy barrier,ensuring rapid li~+***_(22)Sn_(5) alloy provides strong nucleation sites,promoting uniform li ***,in-situ optical microscopy analysis suggests that the synthesized effect fundamentally inhibits lithium dendrite ***,SnSSe modified Cu foil delivered an ultralow nucleation overpotential,superior cycling stability with 450 cycles(Coulombic efficiency,>98%),and excellent plating/stripping behavior over 2200 h at 0.5 mA cm^(-2).Moreover,the brilliant reversible cycles and rate capability were also realized in li@SnSSe//liFePO_(4)(LFP)full cell,shedding light on the feasibility of SnSSe for stable and dendrite-free lithium metal anode.

关键词： lithiophilic li_(22)Sn_(5)alloy High li-ion conductive li_(2)S/li_(2)Se Low nucleation barrier High Coulombic efficiency Dendrite-free li

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基于梯度方向信息熵的印刷电路板缺陷检测

中国机械工程 2017年第6期28卷 695-701页

作者：李云峰李晟阳河南科技大学机电工程学院洛阳471003 机械装备先进制造河南省协同创新中心洛阳471003

针对印刷电路板裸板缺陷在线视觉检测,提出了一种适用于电路板彩色图像的缺陷检测算法。该算法主要通过分析缺陷区域边界像素的梯度方向信息获得对应的典型图像特征,具体由滤波去噪、目标分割和特征提取三部分组成。为减弱环境光干扰同... 详细信息

针对印刷电路板裸板缺陷在线视觉检测,提出了一种适用于电路板彩色图像的缺陷检测算法。该算法主要通过分析缺陷区域边界像素的梯度方向信息获得对应的典型图像特征,具体由滤波去噪、目标分割和特征提取三部分组成。为减弱环境光干扰同时保证边缘细节的清晰,首先在CIE Lab色彩空间对图像进行双边滤波,然后利用该色彩空间的均匀性分割出需要检测的目标区域,最后设计了邻域梯度方向信息熵这一描述子用于提取缺陷特征和构造特征向量,利用支持向量机对缺陷进行识别。实验结果表明:所提算法能够对印刷电路板裸板存在的短路、断路、孔洞、余铜、划痕等常见缺陷进行快速精确的定位,能够满足生产过程中的实时检测要求。

关键词：印刷电路板缺陷检测双边滤波特征提取信息熵

Advanced Potassium-Ion Batteries with High Areal Capacity

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CCS Chemistry 2024年第4期6卷 1011-1023页

作者： Song Chen Jiang Zhong Hongli Deng Qiliang Wei Xiaohua Shen Xinxin Jia shengyang li Qiusheng Zhang Jian Zhu Bingan Lu Weiyou Yang State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringCollege of Materials Science and EngineeringCollege of Physics and ElectronicsHunan Key Laboratory of Two-Dimensional MaterialsEngineering Research Center of Advanced Catalysis of the Ministry of EducationHunan UniversityChangsha 410082 Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingbo 315211

High areal capacity is one of the critically important points for potassium-ion batteries(PIBs)for practical applications,which relies on high areal-massloading electrodes operating at high reversible ***,it is remarkably restricted by the mechanical instability and sluggish charge transfer induced by the increased mass *** overcome such challenge,we report the rationally designed bimetallic selenides CoSe2/SnSe2 heterostructures confined in hierarchical carbon nanofibers(CSSe@CNFs),which enables the electrodes robust mechanical stability,enhanced electron transport,and reduced ion-diffusion energy barrier for facilitating reaction ***,an impressive areal mass loading up to 25.3 mg cm^(−2)was achieved,which endowed a high areal capacity of 7.58 mAh cm^(−2)for such a free-standing *** is stateof-the-art among the PIBs,exceeding that of today’s industry standard(∼3 mAh cm^(−2)for liBs).Furthermore,it delivered long-term stability over 3700 cycles at high current density(∼2 mA cm^(−2),vs 1 mA cm^(−2)in liBs).Moreover,the as-constructed full battery achieved a high energy density of 172.8 Wh kg-1 at 0.05 A g^(−1)with a satisfied cycle stability over 2000 cycles at 2 A g^(−1)and high reversibility with Coulombic efficiency of 100%;thus,signifying its bright future toward commercial application for advanced PIBs.

关键词： bimetal selenides heterostructure mass loading areal capacity potassium-ion battery