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Comprehensive Evaluation Method for Traffic Flow Data Quality based on Grey Correlation Analysis and Particle Swarm Optimization

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 106-128页

作者： Wei ba baojun Chen Qi Li School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian116028China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian116023China

Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or ***,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation *** order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(PSO)and grey correlation analysis(GCA)is presented in this *** first,an improved GCA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is ***,an objective function model of maximum difference of the comprehensive evaluation values is built,and the PSO algorithm is used to optimize the weights of the improved GCA evaluation model based on the objective function ***,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOPSIS-GCA,and 6.86%higher than that of *** proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications.

关键词： Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin ma Yu Hou ba Li He-song Zhang Qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

Star power: harnessing the reactive astrocyte response to promote remyelination in multiple sclerosis

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Neural Regeneration Research 2024年第3期19卷 578-582页

作者： markley Silva Oliveira Junior Laura Reiche Emerson Daniele Ines Kortebi maryam Faiz Patrick Küry Department of Neurology Neuroregeneration laboratoryMedical FacultyHeinrich-Heine-UniversityDüsseldorfGermany Institute of Medical Science University of TorontoTorontoCanada Division of Anatomy Department of SurgeryUniversity of TorontoTorontoCanada

Astrocytes are indispensable for central nervous system development and *** response to injury and disease,astrocytes are integral to the immunological-and the,albeit limited,repair *** this review,we will examine some of the functions reactive astrocytes play in the context of multiple sclerosis and related animal *** will consider the heterogeneity or plasticity of astrocytes and the mechanisms by which they promote or mitigate ***,we will discuss a set of biomedical strategies that can stimulate astrocytes in their promyelinating response.

关键词： astrocytes demyelination drug-based therapies myelin repair oligodendrocyte precursor cells reactive astrogliosis

Hyper spectral resolution stimulated Raman spectroscopy with amplified fs pulse bursts

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Light(Science & Applications) 2024年第3期13卷 566-576页

作者： Hongtao Hu Tobias Flöry Vinzenz Stummer Audrius Pugzlys markus Zeiler Xinhua Xie Aleksei Zheltikov Andrius baltuška Photonics Institute Technische Universität WienGußhausstraße 27-29Vienna A-1040Austria SwissFEL Paul Scherrer InstituteVilligen PSI 5232Switzerland Institute for Quantum Science and Engineering Department of Physics and AstronomyTexas A&M UniversityCollege StationTX 77843USA

We present a novel approach for Stimulated Raman Scattering(SRS)spectroscopy in which a hyper spectral resolution and high-speed spectral acquisition are achieved by employing amplified offset-phase controlled fs-pulse *** investigate the method by solving the coupled non-linear Schrödinger equations and validate it by numerically characterizing SRS in molecular nitrogen as a model *** spectral resolution of the method is found to be determined by the inverse product of the number of pulses in the burst and the intraburst pulse *** SRS spectrum is obtained through a motion-free scanning of the offset phase that results in a sweep of the Raman-shift *** to high spectral resolution and fast motion-free scanning the technique is beneficial for a number SRS-based applications such as gas sensing and chemical analysis.

关键词： compound spectral resolution

Recent progress in the research on magnesium and magnesium alloy foils:A short review

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International Journal of Minerals,Metallurgy and materials 2024年第5期31卷 842-854页

作者： Qiuyan Shen Yongxing ba Peng Zhang Jiangfeng Song Bin Jiang Fusheng Pan National Engineering Research Center for magnesium Alloys Chongqing UniversityChongqing 400044China College of materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific ***,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal *** magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to *** methods have been applied to prepare magnesium alloy *** include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating *** of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for ***,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation,defect control,performance characterization,and application *** advantages and disadvantages of different preparation methods and defect(edge cracks and breakage)mechanisms in the preparation of foils are identified.

关键词： magnesium alloy foil rolling defect performance application

Physics-based seismic analysis of ancient wood structure:fault-to-structure simulation

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 727-740页

作者： ba Zhenning Fu Jisai Wang Fangbo Liang Jianwen Zhang Bin Zhang Long State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation (Tianjin University)Tianjin 300350China School of Civil Engineering Tianjin UniversityTianjin 300350China Administrative Office of the Summer Palace Beijing 100091China School of Architecture Tianjin UniversityTianjin 300072China

based on the domain reduction method,this study employs an SEM-FEM hybrid workflow which integrates the advantages of the spectral element method(SEM)for flexible and highly efficient simulation of seismic wave propagation in a three-dimensional(3D)regional-scale geophysics model and the finite element method(FEM)for fine simulation of structural response including soil-structure interaction,and performs a physics-based simulation from initial fault rupture on an ancient wood *** verification of the hybrid workflow,a large-scale model of an ancient wood structure in the Beijing area,The Tower of Buddhist Incense,is established and its responses under the 1665 Tongxian earthquake and the 1730 Yiheyuan earthquake are *** results from the simulated ground motion and seismic response of the wood structure under the two earthquakes demonstrate that this hybrid workflow can be employed to efficiently provide insight into the relationships between geophysical parameters and the structural response,and is of great significance toward accurate input for seismic simulation of structures under specific site and fault conditions.

关键词： spectral element method finite element method fault-to-structure simulation physical model domain reduction method

Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key Laboratory of Heavy machinery Fluid Power Transmission and Control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Local Joint of Advanced manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

The value of toxicological analysis in acute poisoning patients with uncertain exposure histories:a retrospective and descriptive study from an institute of poisoning

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World Journal of Emergency Medicine 2024年第2期15卷 98-104页

作者： Qifang Shi Gen ba Zhenyu Xia Zhengsheng mao Hao Sun Jinsong Zhang Institute of Poisoning Nanjing Medical UniversityNanjing 211100China Department of Emergency Medicine the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Forensic Medicine Nanjing Medical UniversityNanjing 211166China The Key Laboratory of Modern Toxicology of Ministry of Education Nanjing Medical UniversityNanjing 211166China

baCKGRouND:In clinical practice,some patients might not be able or unwilling to provide a thorough history of medication and poison *** aim of this study was to use toxicological analysis to examine the clinical characteristics of patients with acute poisoning whose exposure history was uncertain from a toxicological analysis ***:This was a retrospective and descriptive study from an institute of *** registration information and test reports spanning the period from April 1,2020 to march 31,2022,were *** with uncertain exposure histories and who underwent toxicological analysis were *** manifestations and categories of toxics were ***:Among the 195 patients with positive toxicological analysis results,the main causes of uncertain exposure history was disturbance of consciousness(62.6%),unawareness(23.6%)and unwillingness or lack of cooperation(13.8%).The predominant clinical manifestations were disturbed consciousness(62.6%),followed by vomiting and nausea(14.4%)and liver function abnormalities(8.7%).A comparison of clinical manifestations between patients with positive and negative(n=99)toxicological analyses results revealed significantly different proportions of disturbances in consciousness(63%vs.21%),dizziness(1.5%vs.5.1%),multi-organ failure(1.5%vs.7.1%),and local pain(0 vs 4%).The main categories of substances involved were psychiatric medications(23.1%),sedatives(20.5%),insecticides(13.8%),and herbicides(12.8%).CONCLUSION:The clinical manifestations of acute poisoning in patients with an uncertain exposure history are diverse and nonspecific,and toxicological analysis plays a pivotal role in the diagnosis and differential diagnosis of such patients.

关键词： Acute poisoning Toxic exposure Toxicological analysis Clinical manifestation

Aggregation of CeAlO_(3) inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and Steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao ba Lun Zhang Wei Chen Ying Ren Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Mechanical and materials Engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3) inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3) and a small amount of Ce_(2)O_(2)S in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3) clusters and small CeAlO_(3) particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3).The maximum diameter of CeA1O_(3) clusters was 1340μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision