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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 not.However,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 method.In 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 paper.At first,an improved GcA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is proposed.Then,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 model.Finally,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 GcA.The 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

Truly optimal semi-active damping to control free vibration of a single degree of freedom system

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 142-145页

作者： Viet Duc la Ngoc Tuan Nguyen Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and optimized.The pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping.

关键词： Analytical optimization Quadratic integral Lyapunov equation Pontryagin maximum principle

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 exposure.The 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 perspective.METHODS:This was a retrospective and descriptive study from an institute of poisoning.Patient registration information and test reports spanning the period from April 1,2020 to March 31,2022,were obtained.Patients with uncertain exposure histories and who underwent toxicological analysis were included.clinical manifestations and categories of toxics were analyzed.RESULTS: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

Review of Networked Microgrid Protection:Architectures,challenges,Solutions,and Future Trends

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cSEE Journal of Power and Energy Systems 2024年第2期10卷 448-467页

作者： Jorge de la cruz Ying Wu John E.candelo-Becerra Juan c.Vasquez Josep M.Guerrero center for Research on Microgrids(cROM) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de Minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. center for Research on Microgrids at UPc(UPc cROM) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain IcREA Pg.Lluis Companys 2308010 BarcelonaSpain center for Research on Microgrids at AAU(AAU cROM) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked microgrids.Various protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and connections.Nevertheless,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected systems.Interconnection of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection operation.This paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their development.First,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review papers.Second,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these systems.Finally,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to implementation.IndexTerms—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

A convolutional neural network to detect possible hidden data in spatial domain images

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cybersecurity 2024年第1期7卷 37-52页

作者： Jean De la croix Ntivuguruzwa Tohari Ahmad Department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African center of Excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the data.Nevertheless,attackers with a steganalysis technique may break them.Existing steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of convolutional Neural Network(cNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based techniques.Though the existing cNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training phase.This research proposes a new method with a cNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain images.The proposed method comprises three phases:pre-processing,feature extraction,and classification.Firstly,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax function.The results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis Deep learning convolutional neural network Infrastructure

Gastric cancer secreted miR 214-3p inhibits the anti-angiogenesis effect of apatinib by suppressing ferroptosis in vascular endothelial cells

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Oncology Research 2024年第3期32卷 489-502页

作者： WEIXUE WANG TONGTONG WANG YAN ZHANG TING DENG HAIYANG ZHANG YI ba Department of GI Medical Oncology Tanjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerTianjin Key Iaboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin300060China

Diferent from necrosis,apoptosis,autophagy and other forms of cell death,ferroptosis is a mechanism that catalyzes lipid peroxidation of polyunsaturated ftty acids under the action of iron divalent or lipoxygenase,leading to cell death.Apatinib is currently used in the third line standard treatment of advanced gastric cancer,targeting the anti-angiogenesis pathway.However,Apatinib mediated ferroptosis in vascular endothelial cells has not been reported yet.Tumor.secreted exosomes can be taken up into target cells to regulate tumor development,but the mechanism related to vascular endothelial cell ferroptosis has not yet been discovered.Here,we show that exosomes secreted by gastric cancer cells carry miR-214.3p into vascular endothelial cells and directdy target zinc finger protein A20 to negatively regulate AcSL4,a key enzyme of lipid peroxidation during frroptosis thereby inhibiting ferroptosis in vascular endothelial cells and reducing the eficiency of Apatinib.In conclusion,inhibition of miR-214-3p can increase the sensitivity of vascular endothelial cells to Apatinib,thereby promoting the antiangiogenic efect of Apatinib,suggesting a potential combination therapy for advanced gastric cancer.

关键词： cellular ferroptosis Exosome Tyrosine kinase inhibitor Gastrointestinal tumors miRNA

ZnSb/Ti_(3)c_(2)T_(x)MXene van der Waals heterojunction for flexible near-infrared photodetector arrays

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Journal of Semiconductors 2024年第5期45卷 99-105页

作者： chuqiao Hu Ruiqing chai Zhongming Wei la Li Guozhen Shen State Key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China center of Materials Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China School of Integrated circuits and Electronics Beijing Institute of TechnologyBeijing 100081China

Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)photodetector.Here,we report the successful fabrication of ZnSb/Ti_(3)c_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography technology.The single ZnSb/Ti_(3)c_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)c_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals heterojunction.Thin polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)c_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending cycles.Moreover,the ZnSb/Ti_(3)c_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application.

关键词： ZnSb nanoplates Ti_(3)c_(2)T_(x)MXene van der Waals heterojunction flexible photodetector image sensing

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 ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To 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 robots.Herein,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 introduced.In 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 herein.This 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 system.Finally,experimental verification is performed using the PcDS performance test platform.The experimental results and quantitative data show that the QFT-DTOc proposed herein can significantly improve the force control performance of the PcDS.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)

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 capacity.However,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal structure.Preparing 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 cracks.Numerous methods have been applied to prepare magnesium alloy foils.They include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating rolling.Defects of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for consideration.Herein,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 prospects.The 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