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Journal of Bionic engineering 2024年第1期21卷 224-235页

作者： Duojin Wang Xiaoping Gu Hongliu Yu Institute of Rehabilitation engineering and technology University of Shanghai for Science and Technology516 Jungong RoadShanghai 200093China Shanghai engineering research center of Assistive Devices 516 Jungong RoadShanghai 200093China

Lower Limb Exoskeletons(LLEs)are receiving increasing attention for supporting activities of daily *** such active systems,an intelligent controller may be *** this paper,we proposed a locomotion intention recognition system based on time series data sets derived from human motion *** of input data and Deep Learning(DL)algorithms,this framework enables the detection and prediction of users’movement *** makes it possible to predict the detection of locomotion modes,allowing the LLEs to provide smooth and seamless *** pre-processed eight subjects were used as input to classify four scenes:Standing/Walking on Level Ground(S/WOLG),Up the Stairs(US),Down the Stairs(DS),and Walking on Grass(WOG).The result showed that the ResNet performed optimally compared to four algorithms(CNN,CNN-LSTM,ResNet,and ResNet-Att)with an approximate evaluation indicator of 100%.It is expected that the proposed locomotion intention system will significantly improve the safety and the effectiveness of LLE due to its high accuracy and predictive performance.

关键词： Lower limb exoskeletons(LLEs) Locomotion intention ResNet Multi-source

A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm

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Chinese Physics B 2024年第7期33卷 233-243页

作者：苏静明方士辉洪炎温言 Anhui Mining Machinery and Electrical Equipment Coordination Innovation center Anhui University of Science and TechnologyHuainan 232001China School of Computer Science and information engineering Hefei University of TechnologyHefei 230009China

A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc.

关键词： color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling

Chromosomal-level genome and metabolome analyses of highly heterozygous allohexaploid Dendrocalamus brandisii elucidate shoot quality and developmental characteristics

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Journal of Integrative Plant Biology 2024年第6期66卷 1087-1105页

作者： Jutang Jiang Zeyu Zhang Yucong Bai Xiaojing Wang Yuping Dou Ruiman Geng Chongyang Wu Hangxiao Zhang Cunfu Lu Lianfeng Gu Jian Gao Key Laboratory of National forestry and Grassland Administration Beijing for Bamboo&Rattan Science and TechnologyInstitute of Gene Science and Industrialization for Bamboo and Rattan ResourcesInternational Center for Bamboo and RattanBeijing 100102China College of forestry Basic Forestry and Proteomics Research CenterFujian Agriculture and Forestry UniversityFuzhou 350002China School of Life Science Peking UniversityBeijing 100871China College of Biological Sciences and Biotechnology Beijing Forestry UniversityBeijing 100083China

Dendrocalamus brandisii(Munro)Kurz is a sympodial bamboo species with inimitable taste and flavorful *** rapid growth and use as high-quality material make this bamboo species highly valued for both food processing and wood ***,genome information for *** is lacking,primarily due to its polyploidy and large genome ***,we assembled a high-quality genome for hexaploid ***,which comprises 70chromosomes with a total size of 2,756 Mb,using long-read Hi Fi ***,we accurately separated the genome into its three constituent *** used Oxford Nanopore Technologies long reads to construct a transcriptomic dataset covering 15 tissues for gene annotation to complement our genome assembly,revealing differential gene expression and post-transcriptional *** integrating metabolome analysis,we unveiled that well-balanced lignin formation,as well as abundant flavonoid and fructose contents,contribute to the superior quality of *** *** genomic,transcriptomic,and metabolomic datasets provided a solid foundation for enhancing bamboo shoot quality and developing efficient gene-editing *** study should facilitate research on *** and enhance its use as a food source and wood material by providing crucial genomic resources.

关键词： bamboo shoots Dendrocalamus brandisii(Munro)Kurz flavonoid genome lignin

Recent advances in FeCl_(3)-photocatalyzed organic reactions via hydrogen-atom transfer

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Chinese Chemical Letters 2024年第9期35卷 32-40页

作者： Xiao-Ya Yuan Cong-Cong Wang Bing Yu Green Catalysis center College of ChemistryZhengzhou UniversityZhengzhou 450001China National engineering research center of Low-Carbon Processing and Utilization of Forest Biomass Nanjing Forestry UniversityNanjing 210037China

In recent years,FeCl_(3)-photocatalyzed direct C–H/Si–H bond functionalization reactions have attracted huge *** those transformations,chlorine radical(Cl·)could be generated from FeCl_(3)via a ligandto-metal charge transfer(LMCT)/homolysis process under light *** resulting chlorine radical subsequently acts as a hydrogen atom transfer(HAT)agent to abstract the hydrogen atom of aliphatic C–H,O–H,or Si–H bonds to give the corresponding C/Si/O-centered radicals for various organic *** this review,we summarized the recent advances in the application of FeCl_(3)as a HAT photocatalyst for the C/Si–H functionalization to construct C–C,C–N,C–Si,C–S,C–B,and C-P bonds.

关键词： FeCl_(3) Photocatalysis Ligand-to-metal charge transfer Hydrogen atom transfer Chlorine radical

Exploring Antarctic subglacial lakes with RECoverable Autonomous Sonde(RECAS):Design and first field tests

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Science China(Technological Sciences) 2024年第6期67卷 1866-1878页

作者： SUN YouHong PAVEL Talalay LI YuanSheng YU HaiBin WANG DongLiang LI GuoPing XU LiPing GONG Da WANG JiXin WANG JianHua WANG Ting ZHANG Nan WANG ZhiGang CHEN YanJi LIU YunChen LI YaZhou PENG ShiLin SHI JianGuang AN ChunLei GE Qun XU Jing NI XiaoKang CUI QiFeng JIANG Qiang MIKHAIL Sysoev Yang Yang WANG RuSheng WEI XianZhe WANG Yu ZHU TianXin DENG ZhiPeng ALEXEY Markov LI Bing FAN XiaoPeng Polar research center Jilin UniversityChangchun130000China School of engineering and technology China University of GeosciencesBeijing100083China Polar research Institute of China Shanghai200120China College of Electronics and information Hangzhou Dianzi UniversityHangzhou310018China Aerospace System engineering Shanghai Shanghai201109China Nanjing Institute of Astronomical Optics&technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing210000China National Ocean technology center Tianjin300000China

Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life *** various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain *** address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)*** technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of *** tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and *** the 38th Chinese National Antarctic research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in *** boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the *** 600 mL of melted water samples were collected from each *** the drilling tests,all systems of the RECAS prototype performed within the expected ranges.

关键词： subglacial lake thermal drilling water sampling Antarctic autonomous sonde

Developing silicon-based photocathodes for CO_(2) conversion

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Science China Chemistry 2024年第6期67卷 1904-1921页

作者： Weijie Zhuang Miao Kan Tao Meng Jinlong Zhang Key Laboratory for Advanced Materials and Joint International research Laboratory of Precision Chemistry and Molecular engineering Feringa Nobel Prize Scientist Joint Research CenterSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Shanghai engineering research center for Multimedia Environmental Catalysis and Resource Utilization East China University of Science and TechnologyShanghai200237China

Photoelectrochemical(PEC)conversion of CO_(2) presents a promising avenue for solar-driven chemical fuel production,with silicon emerging as a cost-effective and high-light-absorbing material pivotal to this *** at exploring opportunities for industrializing PEC CO_(2) reduction(PEC-CO_(2)R)by minimizing reaction energy consumption,enhancing reaction efficiency and selectivity,this review summarizes recent advancements in developing Si-based photocathodes for PEC-CO_(2)*** outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance *** on this understanding,the strategies to enhance the performance of the PEC-CO_(2)R system,including light absorption,charge separation,and catalytic reactions are categorized as the interfacial modification,active site decoration,and protective layer *** design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been ***,this review scrutinizes the influence of the photocathodic chemical *** review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PEC-CO_(2)R *** this wealth of information offers an up-to-date perspective on the dynamic developments in silicon-based PEC-CO_(2) conversion and underscores the promising pathways toward the sustainable fuel synthesis from pollutant CO_(2).

关键词： photoelectrochemistry solar fuels silicon photocathodes carbon dioxide reduction microenvironment

Combinations of electron and proton donors in transition-metal complex mediated nitrogen reduction reactions

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Science China Chemistry 2024年第7期67卷 2136-2154页

作者： Delong Han Li Yang Hao Huang Priyanka Chakraborty Shashikant U.Dighe Kuo-Wei Huang KAUST Catalysis center and Division of Physical Science and engineering King Abdullah University of Science and TechnologyThuwal 23955Saudi Arabia Agency for Science Technologyand ResearchInstitute of Materials Research and Engineering and Institute of Sustainability for ChemicalsEnergy and EnvironmentSingapore 138634Singapore

Nitrogen fixation is a complex process involving the transfer of six electrons and *** from the conventional Haber-Bosch process,which relies on hydrogen(H_(2))to provide both electrons and protons to reduce nitrogen(N_(2)),homogeneous transition metal complex-catalyzed N_(2)reduction reactions(NRR)employ an array of electron and proton donors or even electron donors combined with *** the synthesis of diverse catalytic progress,the categories of donors have seen rapid ***,existing literature only provides summaries regarding the metal,ligands,and *** the significance of electron and proton donor combinations in nitrogen reduction reactions,no literature has thoroughly reviewed this ***,we hereby compiled a comprehensive list of commonly used reagents in N_(2)reduction and classified them according to their specific donor *** review presents clear and organized information about these combinations,along with a summary of their general performance trend in NRR with related ***,we conclude the discussion by highlighting key points for researchers to consider when selecting catalysts and donor combinations,with the ultimate goal of advancing the field of nitrogen fixation.

关键词： dinitrogen reduction reaction reducing donor combination transition metal complexes homogeneous catalysis

Detecting Double Mixed Compressed Images Based on Quaternion Convolutional Neural Network

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Chinese Journal of Electronics 2024年第3期33卷 657-671页

作者： Hao WANG Jinwei WANG Xuelong HU Bingtao HU Qilin YIN Xiangyang LUO Bin MA Jinsheng SUN Department of Automation Nanjing University of Science and Technology engineering research center of Digital Forensics Ministry of Education Department of Computer and Software Nanjing University of Information Science and Technology School of Management Nanjing University of Posts and Telecommunications Department of Computer Science and engineering Guangdong Province Key Laboratory of Information Security Technology Sun Yat-sen University State Key Laboratory of Mathematical engineering and Advanced Computing Qilu University of technology

Detection of color images that have undergone double compression is a critical aspect of digital image *** the existence of various methods capable of detecting double Joint Photographic Experts Group(JPEG) compression,they are unable to address the issue of mixed double compression resulting from the use of different compression *** particular,the implementation of Joint Photographic Experts Group 2000(JPEG2000)as the secondary compression standard can result in a decline or complete loss of performance in existing *** tackle this challenge of JPEG+JPEG2000 compression,a detection method based on quaternion convolutional neural networks(QCNN) is *** QCNN processes the data as a quaternion,transforming the components of a traditional convolutional neural network(CNN) into a quaternion *** relationships between the color channels of the image are preserved,and the utilization of color information is ***,the method includes a feature conversion module that converts the extracted features into quaternion statistical features,thereby amplifying the evidence of double *** results indicate that the proposed QCNN-based method improves,on average,by 27% compared to existing methods in the detection of JPEG+JPEG2000 compression.

关键词： Image coding Image color analysis Quaternions Forensics Transform coding Color Feature extraction

Dynamics Modeling and Parameter Identification for a Coupled-Drive Dual-Arm Nursing Robot

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Chinese Journal of Mechanical engineering 2024年第4期 256-270页

作者： Hao Lu Zhiqiang Yang Deliang Zhu Fei Deng Shijie Guo College of Electronic information and Automation Tianjin University of Science and Technology Academy for engineering & technology Fudan University Shanghai engineering research center of AI & Robotics School of Mechanical engineering Hebei University of Technology

A dual-arm nursing robot can gently lift patients and transfer them between a bed and a wheelchair. With its lightweight design, high load-bearing capacity, and smooth surface, the coupled-drive joint is particularly well suited for these robots. However, the coupled nature of the joint disrupts the direct linear relationship between the input and output torques, posing challenges for dynamic modeling and practical applications. This study investigated the transmission mechanism of this joint and employed the Lagrangian method to construct a dynamic model of its internal dynamics. Building on this foundation, the Newton-Euler method was used to develop a dynamic model for the entire robotic arm. A continuously differentiable friction model was incorporated to reduce the vibrations caused by speed transitions to zero. An experimental method was designed to compensate for gravity, inertia,and modeling errors to identify the parameters of the friction model. This method establishes a mapping relationship between the friction force and motor current. In addition, a Fourier series-based excitation trajectory was developed to facilitate the identification of the dynamic model parameters of the robotic arm. Trajectory tracking experiments were conducted during the experimental validation phase, demonstrating the high accuracy of the dynamic model and the parameter identification method for the robotic arm. This study presents a dynamic modeling and parameter identification method for coupled-drive joint robotic arms, thereby establishing a foundation for motion control in humanoid nursing robots.

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Achieving high-performance sodium metal anodes: From structural design to reaction kinetic improvement

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Nano research 2024年第3期17卷 1288-1312页

作者： Jing Xu Jianhao Yang Yashuang Qiu Yang Jin Tianyi Wang Bing Sun Guoxiu Wang research center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China College of Chemistry and Chemical engineering Yangzhou University Yangzhou 225009China Centre for Clean Energy technology School of Mathematical and Physical SciencesFaculty of ScienceUniversity of Technology SydneyUltimoNSW 2007Australia

Sodium metal is one of the ideal anodes for high-performance rechargeable batteries because of its high specific capacity(~1166 mAh·g^(-1)),low reduction potential(-2.71 V compared to standard hydrogen electrodes),and low ***,the unstable solid electrolyte interphase,uncontrolled dendrite growth,and inevitable volume expansion hinder the practical application of sodium metal *** present,many strategies have been developed to achieve stable sodium metal ***,we systematically summarize the latest strategies adopted in interface engineering,current collector design,and the emerging methods to improve the reaction kinetics of sodium deposition ***,the strategies of constructing protective layers are reviewed,including inorganic,organic,and mixed protective layers through electrolyte additives or ***,the classification of metal-based,carbon-based,and composite porous frames is discussed,including their function in reducing local deposition current density and the effect of introducing sodiophilic ***,the recent progress of alloys,nanoparticles,and single atoms in improving Na deposition kinetics is systematically ***,the future research direction and the prospect of high-performance sodium metal batteries are proposed.

关键词： sodium metal anodes interface engineering current collector design reaction kinetics sodium deposition processes