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IEEE/cAA Journal of Automatica Sinica 2024年第8期11卷 1892-1894页

作者： Tao chen Ruiyuan Zhao Jian chen Zichao Zhang college of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Agricultural Technology in Tropical South china Ministry of Agriculture and Rural AffairsGuangzhou 510642China

dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(AdRc)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which AdRc is a data-driven model-free control algorithm that only relies on the input and output data of the *** on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real *** and experiment show the FIIL-AdRc scheme has better control performance.

关键词： Active scheme iterative

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Path-dependent Progressive Failure Analysis for 3d-Printed continuous carbon Fibre Reinforced composites

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chinese Journal of mechanical Engineering 2024年第4期 97-106页

作者： Yuan chen Lin Ye School of System design and Intelligent manufacturing (SdIm) Southern University of Science and Technology Shenzhen Key Laboratory of Intelligent manufacturing for continuous carbon Fibre Reinforced composites Southern University of Science and Technology

In order to predict the damage behaviours of 3d-printed continuous carbon fibre(ccF) reinforced composites,when additional short carbon fibre(ScF) composite components are employed for continuous printing or special functionality, a novel path-dependent progressive failure(PdPF) numerical approach is developed. First, a progressive failure model using Hashin failure criteria with continuum damage mechanics to account for the damage initiation and evaluation of 3d-printed ccF reinforced polyamide(PA) composites is developed, based on actual fibre placement trajectories with physical measurements of 3d-printed ccF/PA constituents. meanwhile, an elastic-plastic model is employed to predict the plastic damage behaviours of ScF/PA parts. Then, the accuracy of the PdPF model was validated so as to study 3d-printed ccF/PA composites with either negative Poisson's ratio or high stiffness. The results demonstrate that the proposed PdPF model can achieve higher prediction accuracies in mechanical properties of these 3d-printed ccF/PA composites. mechanism analyses show that the stress distribution is generally aggregated in the ccF areas along the fibre placement paths, and the shear damage and matrix tensile/compressive damage are the key damage modes. This study provides a new approach with valuable information for characterising complex 3d-printed continuous fibre-matrix composites with variable mechanical properties and multiple constituents.

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Global optimization of double protograph LdPc codes for JScc scheme

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Science china(Information Sciences) 2024年第6期67卷 455-456页

作者： Qiwang chen chen chen Yu-cheng HE Zhiping XU Xiamen Key Laboratory of mobile multimedia communications College of Information Science and EngineeringHuaqiao University Key Laboratory of Underwater Acoustic communication and marine Information Technology (Xiamen University) Ministry of Education School of Ocean Information Engineering Jimei University

A double low-density parity-check (d-LdPc) coding system was proposed in[1]as a typical joint source-channel coding(JScc) scheme[1–5].In this system,two LdPc coding matrices perform source and channel coding,*** important concept in a d-LdPc coding system is the introduction of a linking matrix between the check nodes (cNs)of the source coding matrix and the variable nodes (VNs) of the channel LdPc coding matrix.

关键词： JOINT SOURcE dESIGN

Revealing Tissue Heterogeneity and Spatial dark Genes from Spatially Resolved Transcriptomics by multiview Graph Networks

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Research 2024年第2期6卷 629-645页

作者： Ying Li Yuejing Lu chen Kang Peiluan Li Luonan chen School of mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China Longmen Laboratory LuoyangHenan471003China Key Laboratory of Systems Biology Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai201100China Key Laboratory of Systems Health Science of Zhejang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China School of Life Science and Technology ShanghaiTech UniversityShanghai201100.China

Spatially resolved transcriptomics(SRT)is capable of comprehensively characterizing gene expression patterns and providing an unbiased image of spatial *** fully understand the organizational complexity and tumor immune escape mechanism,we propose stmGATF,a multiview graph attention fusion model that integrates gene expression,histological images,spatial location,and gene *** better extract information,stmGATF exploits SimcLRv2 for visual feature exaction and employs edge feature enhanced graph attention networks for the learning potential embedding of each view.A global attention mechanism is used to adaptively integrate 3 views to obtain low-dimensional *** to diverse SRT datasets,stmGATF is robust and outperforms other methods in detecting spatial domains and denoising data even with different resolutions and *** particular,stmGATF contributes to the elucidation of tissue heterogeneity and extraction of 3-dimensional expression ***,considering the associations between genes in tumors,stmGATF can identify the spatial dark genes ignored by traditional methods,which can be used to predict tumor-driving transcription factors and reveal tumor immune escape mechanisms,providing theoretical evidence for the development of new immunotherapeutic strategies.

关键词： Spatial integrate driving

NSNO:Neumann Series Neural Operator for Solving Helmholtz Equations in Inhomogeneous medium

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Journal of Systems Science & complexity 2024年第2期37卷 413-440页

作者： chen Fukai LIU Ziyang LIN Guochang chen Junqing SHI Zuoqiang department of mathematical Sciences Tsinghua UniversityBeijing 100084China Yau mathematical Sciences center Tsinghua UniversityBeijing 100084China Yanqi Lake Beijing Institute of mathematical Sciences and Applications Beijing 101408China

In this paper,the authors propose Neumann series neural operator(NSNO)to learn the solution operator of Helmholtz equation from inhomogeneity coefficients and source terms to *** equation is a crucial partial differential equation(PdE)with applications in various scientific and engineering ***,efficient solver of Helmholtz equation is still a big challenge especially in the case of high ***,deep learning has shown great potential in solving PdEs especially in learning solution *** by Neumann series in Helmholtz equation,the authors design a novel network architecture in which U-Net is embedded inside to capture the multiscale *** experiments show that the proposed NSNO significantly outperforms the state-of-the-art FNO with at least 60%lower relative L^(2)-error,especially in the large wavenumber case,and has 50%lower computational cost and less data ***,NSNO can be used as the surrogate model in inverse scattering *** tests show that NSNO is able to give comparable results with traditional finite difference forward solver while the computational cost is reduced tremendously.

关键词： Helmholtz equation inverse problem neumann series neural network solution operator

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Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of minerals,metallurgy and materials 2024年第7期31卷 1540-1553页

作者： Jingcheng Wang Zhentong Liu Wei chen Hongliang chen Lifeng Zhang School of mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of materials Science and Engineering Tianjin UniversityTianjin 300350China School of mechanical and materials Engineering North China University of TechnologyBeijing 100144China

A 3d mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(cc)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UdS)***,the user-defined function(UdF)was used to describe the source term in the UdS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

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comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 143-154页

作者： chuan Li Hong-Xia chen Yan-Hua Lai department of Transplantation People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina department of clinical Pharmacy People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina

BAcKGROUNd The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant *** To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).mETHOdS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from december 2019 to June *** This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional *** 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative *** NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUc)=0.861,Pd severe complications(AUc=0.643,P=0.011).compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,model for End-stage Liver disease scores and prothrombin time(Pmore,the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding,primary graft nonfunction,and *** The NRI has good predictive value for 30-d mortality and severe complications following *** NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy.

关键词： Liver transplantation Nutritional indicator complications Prognosis Nutrition assessment

Astragaloside IV Alleviates Acute Liver Failure Induced by d-GalN/LPS by Upregulating Autophagy and Reducing Inflammation

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Infectious microbes & diseases 2024年第1期6卷 20-28页

作者： meng Hong Wenwen Lian Ying Yang Zhi chen State Key Laboratory for diagnosis and Treatment of Infectious diseases National Clinical Research Center for Infectious DiseasesNational Medical Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhouChina

Acute liver failure(ALF)is a life-threatening condition that manifests in an extremely serious manner and progresses *** following study investigated the protective effect of astragaloside IV(AS-IV),a traditional chinese drug,on ALF,and its underlying mechanisms,focusing on autophagy and inflammation *** were randomly divided into a saline group,a d-galactosamine and lipopolysac-charide(d-GalN/LPS)group and an AS-IV *** analysis,immunohistochemistry,cytometric bead array,high-throughput quantitative PcR,flow cytometry and Western analysis were used to assess inflammation and liver damage 5 hours after d-GalN/LPS *** IV treatment reduced mortality by alleviating d-GalN/LPS–induced hepatic damage and decreasing inflammation(decreasing Ly6c+monocyte levels,reducing inflammatory cytokines and increasing anti-inflammatory factors)as well as upregulating ***,PcR array was used to detect expression of autophagy-related genes,which demonstrated a Log2 fold change in gene expression between the AS-IV and d-GalN/LPS groups ranging from 1.19 to-3.53,with Tnfsf10 showing the largest alteration be-tween the two *** data suggest that AS-IV may alleviate ALF by upregulating autophagy and reducing inflammation,and it may therefore be an interesting drug for alleviating ALF.

关键词： astragaloside IV acute liver failure inflammation autophagy

Rail-PillarNet: A 3d detection Network for Railway Foreign Object Based on LidAR

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computers, materials and continua 2024年第3期80卷 3819-3833页

作者： Li, Fan Zhang, Shuyao Yang, Jie Feng, Zhicheng chen, Zhichao School of Electrical Engineering and Automation Jiangxi University of Science and Technology Ganzhou 341000 China Jiangxi Provincial Key Laboratory of maglev Technology Ganzhou 341000 China School of Information Engineering Jiangxi University of Science and Technology Ganzhou 341000 China

Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional (2d) images, such as short detection distance, strong influence of environment and lack of distance information, we propose Rail-PillarNet, a three-dimensional (3d) LIdAR (Light detection and Ranging) railway foreign object detection method based on the improvement of PointPillars. Firstly, the parallel attention pillar encoder (PAPE) is designed to fully extract the features of the pillars and alleviate the problem of local fine-grained information loss in PointPillars pillars encoder. Secondly, a fine backbone network is designed to improve the feature extraction capability of the network by combining the coding characteristics of LIdAR point cloud feature and residual structure. Finally, the initial weight parameters of the model were optimised by the transfer learning training method to further improve accuracy. The experimental results on the OSdaR23 dataset show that the average accuracy of Rail-PillarNet reaches 58.51%, which is higher than most mainstream models, and the number of parameters is 5.49 m. compared with PointPillars, the accuracy of each target is improved by 10.94%, 3.53%, 16.96% and 19.90%, respectively, and the number of parameters only increases by 0.64 m, which achieves a balance between the number of parameters and accuracy. copyright © 2024 The Authors. Published by Tech Science Press.

关键词： Railroads

How can Practitioners Support citizen Volunteers in disaster Risk Reduction? Insight from “Good and Ready” in Aotearoa New Zealand

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International Journal of disaster Risk Science 2024年第03期15卷 374-387页

作者： Lo?c Le dé Steve Ronoh Ei mon Thinn Kyu Brigitte Rive School of Public Health and Interdisciplinary Studies Auckland University of Technology Pacific Health Research centre Auckland University of Technology New Zealand Red cross

Global and national policy frameworks emphasize the importance of people's participation and volunteers' role in disaster risk reduction. While research has extensively focused on volunteers in disaster response and recovery, less attention has been paid on how organizations involved in disaster risk management can support volunteers in leading and coordinating communitybased disaster risk reduction. In 2019, the New Zealand Red cross piloted the Good and Ready initiative in Auckland,Aotearoa New Zealand, with the objective to empower local people in resilience building with a focus on volunteers and community participation. This research examined the positive and negative outcomes of Good and Ready and investigated volunteers' experiences in the disaster resilience initiative. It involved the codesign of a questionnaire-based survey using participatory methods with Good and Ready volunteers, the dissemination of the survey to gather volunteers' viewpoints, and a focus group discussion with participatory activities with Red cross volunteers. The findings highlight that a key challenge lies in finding a balance between a program that provides flexibility to address contextual issues and fosters communities' ownership, versus a prescriptive and standardized approach that leaves little room for creativity and self-initiative. It pinpoints that supporting volunteers with technical training is critical but that soft skills training such as coordinating, communicating,or facilitating activities at the local level are needed. It concludes that the sustainability of Good and Ready requires understanding and meeting volunteers' motivations and expectations and that enhancing partnerships with local emergency management agencies would strengthen the program.

关键词： community-based approach disaster risk reduction New Zealand Participation Volunteers