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Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

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Research in Astronomy and Astrophysics 2024年第3期24卷 194-204页

作者： Pei-xin luo Bao-lin Tan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific ***,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly *** on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred *** on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction *** for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle *** peak year will occur approximately in 2024,and the period will be about 11±1 *** for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr.

关键词： Sun activity-Sun evolution-(Sun) sunspots-methods data analysis

Jurassic integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1195-1228页

作者： Jianguo LI xin RAO lin MU Xiaohui CUI xin LI Hui luo Peixue LIU Center for Excellence in Life and Paleoenvironment Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Nanjing College University of Chinese Academy of SciencesNanjing 211135China

The Qinghai-Tibetan Plateau experienced a unique geological evolution during the Jurassic,driven by the termination of the Palaeotethys and the reduction of the *** Indian Plate separated from the northern margin of Gondwana and drifted northward from the Southern *** that the timing of strata serves as the basis for reconstructing geological history,the present work aimed to develop a new multiple stratigraphic and chronologic framework for the Jurassic strata of the Qinghai-Tibetan Plateau region via a synthesis of the material on lithostratigraphy,palaeontology,iso-radiometric dating,magnetostratigraphy,and other techniques with an emphasis on recent progress and *** new framework included the Jurassic System from the four major subdivisions of the plateau:the Baryan Har,Qiangtang,Lhasa-Gandise,and Southern Xizang(Himalaya).Ultimately,a more complete,refined biostratigraphic sequence was proposed,comprising the most common fossils in the plateau and those that are stratigraphically significant for the Jurassic stratigraphy,including ammonites,bivalves,brachiopods,foraminifera,radiolarians,and dinoflagellate cysts for the marine strata,and pollen and spores,and charophytes for the terrestrial *** biostratigraphic framework was correlated with the Jurassic international standard zonation of the Geological Time Scale 2020 via standard or representative species or genera of *** on this framework,we constructed a lateral correlation of the Jurassic strata between different basins of the *** palaeontologic correlation in the present work shows that the Lhasa-Gandise Block had a closer relationship with the Qiangtang Block than with the Southern Xizang Himalaya during the Jurassic ***,the Lhasa-Gandise Block and Qiangtang Block shared similar marine fauna features of the north marginal East *** contrasts the opinion suggesting that the Yarlung Zangbo Tethys was a small back-arc basin.A c

关键词： Biostratigraphy Chronostratigraphy Correlation Yarlung Zangbo suture Bangong Co-Nujiang suture Tethys

Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： xin Fu Zhen Lu Shen Li Zheng-Hong luo lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

Data Driven Vibration Control:A Review

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1898-1917页

作者： Weiyi Yang Shuai Li xin luo Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714 Chongqing School University of Chinese Academy of SciencesChongqing 400714China Faculty of Information Technology and Electrical Engineering University of OuluOulu 90570 VTT-Technology Research Center of Finland Oulu 90570Finlan College of Computer and Information Science Southwest UniversityChongqing 400715China

With the ongoing advancements in sensor networks and data acquisition technologies across various systems like manufacturing,aviation,and healthcare,the data driven vibration control(DDVC)has attracted broad interests from both the industrial and academic *** shaping(IS),as a simple and effective feedforward method,is greatly demanded in DDVC *** convolves the desired input command with impulse sequence without requiring parametric dynamics and the closed-loop system structure,thereby suppressing the residual vibration *** on a thorough investigation into the state-of-the-art DDVC methods,this survey has made the following efforts:1)Introducing the IS theory and typical input shapers;2)Categorizing recent progress of DDVC methods;3)Summarizing commonly adopted metrics for DDVC;and 4)Discussing the engineering applications and future trends of *** doing so,this study provides a systematic and comprehensive overview of existing DDVC methods from designing to optimizing perspectives,aiming at promoting future research regarding this emerging and vital issue.

关键词： Data driven vibration control(DDVC) data science designing method feedforward control industrial robot input shaping optimizing method residual vibration

SDGNN: Symmetry-Preserving Dual-Stream Graph Neural Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1717-1719页

作者： Jiufang Chen Ye Yuan xin luo the College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 the Chongqing Key Laboratory of Big Data and Intelligent Computing Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China the College of Computer and Information Science Southwest UniversityChongqing 400715China IEEE

Dear Editor,This letter proposes a symmetry-preserving dual-stream graph neural network(SDGNN) for precise representation learning to an undirected weighted graph(UWG). Although existing graph neural networks(GNNs) are influential instruments for representation learning to a UWG, they invariably adopt a unique node feature matrix for illustrating the sole node set of a UWG.

关键词： representation preserving undirected

A Self-Attention Based Dynamic Resource Management for Satellite-Terrestrial Networks

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China Communications 2024年第4期21卷 136-150页

作者： lin Tianhao luo Zhiyong School of Electronics and Communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Peng Cheng Laboratory Shenzhen 518107China

The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power support,which is an important development direction of future *** this paper,we take into account a multi-scenario network model under the coverage of low earth orbit(LEO)satellite,which can provide computing resources to users in faraway areas to improve task processing ***,LEO satellites experience limitations in computing and communication resources and the channels are time-varying and complex,which makes the extraction of state information a daunting ***,we explore the dynamic resource management issue pertaining to joint computing,communication resource allocation and power control for multi-access edge computing(MEC).In order to tackle this formidable issue,we undertake the task of transforming the issue into a Markov decision process(MDP)problem and propose the self-attention based dynamic resource management(SABDRM)algorithm,which effectively extracts state information features to enhance the training *** results show that the proposed algorithm is capable of effectively reducing the long-term average delay and energy consumption of the tasks.

关键词： mobile edge computing resource management satellite-terrestrial networks self-attention

Dynamic motion of quadrupedal robots on challenging terrain:a kinodynamic optimization approach

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Frontiers of Mechanical Engineering 2024年第3期19卷 23-40页

作者： Qi LI Lei DING xin luo Engineering Research Center of Hubei Province for Clothing Information Wuhan 430200China School of Computer Science and Artificial Intelligence Wuhan Textile UniversityWuhan 430200China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

The dynamic motion of quadrupedal robots on challenging terrain generally requires elaborate spatial–temporal kinodynamic motion planning and accurate control at higher refresh rate in comparison with regular ***,conventional quadrupedal robots usually generate relatively coarse planning and employ motion replanning or reactive strategies to handle terrain *** resultant complex and computation-intensive controller may lead to nonoptimal motions or the breaking of locomotion *** this paper,a kinodynamic optimization approach is *** generate long-horizon optimal predictions of the kinematic and dynamic behavior of the quadruped robot on challenging terrain,we formulate motion planning as an optimization problem;jointly treat the foot’s locations,contact forces,and torso motions as decision variables;combine smooth motion and minimal energy consumption as the objective function;and explicitly represent feasible foothold region and friction constraints based on terrain *** track the generated motions accurately and stably,we employ a whole-body controller to compute reference position and velocity commands,which are fed forward to joint controllers of the robot’s *** verify the effectiveness of the developed approach through simulation and on a physical quadruped robot *** show that the quadruped robot can successfully traverse a 30°slope and 43% of nominal leg length high step while maintaining the rhythm of dynamic trot gait.

关键词： quadrupedal robot kinodynamic planning nonlinear optimization challenging terrain whole-body control

Microstructure evolution of Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)amorphous alloy after semi-solid isothermal treatment

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China Foundry 2024年第3期21卷 287-294页

作者： xin-hua Huang Jing-wen Pu Yong-xin luo Yue-jun Ouyang School of Material Electricity and Intelligent ManufacturingHuaihua UniversityHuaihua 330031HunanChina Hunan Renewable Aluminum Innovation Research Center Huaihua UniversityHuaihua 330031HunanChina

The as-cast amorphous Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)composites,comprising in situ formedβ-Ti ductile crystalline precipitates,were prepared by water cooled copper mold suction ***,the semi-solid composites were obtained after the as-cast composites were treated by semi-solid isothermal *** microstructure evolution and kinetics of the composites were *** show that the microstructures of both the as-cast and semi-solid composites comprise ofβ-Ti crystal phases and amorphous matrix *** and after treatment,the crystals evolve from fine granular or fine dendritic crystals to coarse *** the treatment temperature increasing or the time prolonging,the average crystal size gradually increases and the surface morphology of the crystals gradually becomes *** studying the microstructural evolution and dynamics during the isothermal treatment process,it is found that the final morphology ofβ-Ti crystals is influenced by the isothermal treatment temperature and time(t),and theβ-Ti evolution rate increases with an increase in treatment *** addition,a linear relationship was observed between the size of cubicβ-Ti crystals(D^(3))and t;the growth kinetics factor K is 3.8μm^(3)·s^(-1).As the K value closes to 4μm^(3)·s^(-1),it is inferred the morphology evolution ofβ-Ti crystals is a coarsening behavior controlled by the diffusion of solute elements.

关键词： Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14) amorphous matrix composites semi-solid as-cast microstructure

Quick Weighing of Passing Vehicles Using the Transfer-Learning-Enhanced Convolutional Neural Network

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2507-2524页

作者： Wangchen Yan Jinbao Yang xin luo College of Civil Engineering Xiangtan UniversityXiangtan411105China Energy&Environmental Engineering Department China CEC Engineering CorporationChangsha410114China

Transfer learning could reduce the time and resources required by the training of new models and be therefore important for generalized applications of the trainedmachine learning *** this study,a transfer learningenhanced convolutional neural network(CNN)was proposed to identify the gross weight and the axle weight of moving vehicles on the *** proposed transfer learning-enhanced CNN model was expected to weigh different bridges based on a small amount of training datasets and provide high identification *** of all,a CNN algorithm for bridge weigh-in-motion(B-WIM)technology was proposed to identify the axle weight and the gross weight of the typical two-axle,three-axle,and five-axle vehicles as they crossed the bridge with different loading routes and ***,the pre-trained CNN model was transferred by fine-tuning to weigh themoving vehicle on another ***,the identification accuracy and the amount of training data required were compared between the two CNN *** showed that the pre-trained CNN model using transfer learning for B-WIM technology could be successfully used for the identification of the axle weight and the gross weight for moving vehicles on another bridge while reducing the training data by 63%.Moreover,the recognition accuracy of the pre-trained CNN model using transfer learning was comparable to that of the original model,showing its promising potentials in the actual applications.

关键词： Bridge weigh-in-motion transfer learning convolutional neural network