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Friction 2024年第1期12卷 74-94页

作者： Jiabao yin chun LU Jiliang MO School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Chengdu 610031China

A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this *** wear degradation considering the influence of temperature(T)is predicted by Archard wear model with the help of the UMESHMOTION subroutine and arbitrary Lagrangian–Eulerian(ALE)remeshing *** the proposed method,the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy(PM)friction block are studied *** effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature,wear degradation,friction noise and vibration,and contact status *** work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

关键词： tribological behaviors thermomechanical field wear prediction finite element simulation disc brake system railway vehicle

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： chun yin JIN Shuang Zhi LI College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

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Chinese Geographical Science 2024年第3期34卷 453-467页

作者： HUANG Xiaoyan KANG Chenchen yin chun TANG Junqing Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China International Institute of Spatial Lifecourse Health(ISLE) Wuhan UniversityWuhan 430079China School of Urban Planning and Design Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Key Laboratory of Earth Surface System and Human-Earth Relations of Ministry of Natural Resources of China Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

Transportation accessibility has been treated as an important means of reducing the urban-rural income ***,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial *** on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial *** result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle *** urban-rural income disparity exhibits strong spatial clustering *** highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect ***,there is a substitution effect between highway accessibility and railway accessibility in the whole ***,these associations differ in geographic *** the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway *** the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway *** conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial *** and railways should be developed in a coordinated manner to promote an integrated transport network system.

关键词： transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China

Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition

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Computers, Materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-chun Lai Shu-yin Chiang Yao-Chiang Kan Hsueh-chun Lin Department of Public Health China Medical UniversityTaichung406040Taiwan Department of Information and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan Department of Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan Department and Institute of Health Service Administrations China Medical UniversityTaichung406040Taiwan

Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation *** study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in *** analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the ***,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDM database,renowned for its challenging features,supports the framework’s resilience and *** ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVM),and random forest(RF),for data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature ***,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model *** best accuracies of the ANFIS,SVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,*** analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVM,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,***,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications.

关键词： Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination

RB-DEM Modeling and Simulation of Non-Persisting Rough Open Joints Based on the IFS-Enhanced Method

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 337-359页

作者： Hangtian Song Xudong Chen chun Zhu Qian yin Wei Wang Qingxiang Meng Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Research Institute of Geotechnical Engineering Hohai UniversityNanjing210098China School of Earth Sciences and Engineering Hohai UniversityNanjing210098China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China

When the geological environment of rock masses is disturbed,numerous non-persisting open joints can appear within *** is crucial to investigate the effect of open joints on the mechanical properties of rock ***,it has been challenging to generate realistic open joints in traditional experimental tests and numerical *** paper presents a novel solution to solve the *** utilizing the stochastic distribution of joints and an enhanced-fractal interpolation system(IFS)method,rough curves with any orientation can be *** Douglas-Peucker algorithm is then applied to simplify these curves by removing unnecessary points while preserving their fundamental ***,open joints are created by connecting points that move to both sides of rough curves based on the aperture *** modeling is performed to construct the final mesh ***,the RB-DEM method is applied to transform the mesh model into a discrete element model containing geometric information about these open ***,this study explores the impacts of rough open joint orientation,aperture,and number on rock fracture *** method provides a realistic and effective approach for modeling and simulating these non-persisting open joints.

关键词： Non-persisting rough open joints stochastic distribution of joints enhanced-IFS method RB-DEM

Aggressive fibromatosis of the sigmoid colon:A case report

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3716-3722页

作者： Pan-Pan Yu Xin-chun Liu Lu yin Guang yin Department of Gastrointestinal and Anal Surgery The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina Department of Gastric Surgery Zhejiang Cancer HospitalHangzhou 310022Zhejiang ProvinceChina Department of Pathology The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Aggressive fibromatosis(AF),also known as desmoid tumor or desmoid-type fibromatosis,is a rare soft tissue neoplasm that can occur in almost any part of the *** it is a benign disease,AF is aggressive and infiltrative and has a high recurrence rate after *** sites for intra-abdominal AF are the small bowel mesentery,retroperitoneum,and *** in the colon is extremely *** SUMMARY Here,we report the first case of sigmoid colon AF,which was accidentally discovered in a 27-year-old woman during laparoscopic *** tomography confirmed a slightly enhanced mass in the sigmoid *** colonoscopy did not reveal a mass in the colonic lumen,but a suspected external compress was found in the sigmoid *** disease involving a gastrointestinal stromal tumor was *** patient underwent laparoscopic exploration,and sigmoidectomy with a negative margin was performed to excise the *** immunohistochemistry revealed that the mass was an *** patient recovered well and was recurrence-free at the 30-month follow-up without adjuvant *** AF should be considered in the differential diagnosis of subepithelial colon *** resection alone can achieve good outcomes.

关键词： Aggressive fibromatosis Desmoid tumor Sigmoid mass Subepithelial tumor Case report

Single-pilot operations in commercial flight:Effects on neural activity and visual behaviour under abnormalities and emergencies

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Chinese Journal of Aeronautics 2024年第8期37卷 277-292页

作者： Qinbiao LI chun-Hsien CHEN Kam K.H.NG Xin YUAN Cho yin YIU Human Factors and Ergonomics Laboratory Department of Aeronautical and Aviation EngineeringThe Hong Kong Polytechnic UniversityHong Kong Special Administrative Region 100872China School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

With cutting-edge technologies and considering airline human-resource-saving,a single pilot in commercial jets could be technically *** changes in captains’natural behaviours are initially required to comprehend the specific safe human performance envelope for safeguarding single-pilot flight,particularly in high-risk *** paper investigates how captains’performance transforms for fixing emergencies when operating from Dual-Pilot Operations(DPO)to Single-Pilot Operations(SPO)through a physiological-based *** pilots flew an emergency-included flight with/without first officers’*** neural activities and scanning behaviours were recorded using a 32-channel Electroencephalogram(EEG)and glasses-based eye tracker,with the observation and post-experiment questionnaires to evaluate the flight operations and pilots’*** alone,there was a significantly increased cortical activity in h and b waves over the frontal,parietal,and temporal lobes during the more complicated emergencies,and pilots focused less on the primary flight display while spending significantly more time scanning the other *** physiological fluctuating patterns associated with risky operations in SPO were highlighted by cross-correlating multimodal *** experimental-based noteworthy insights may wish to inform commercial SPO measures to lessen the persistent physiological fluctuation,assisting airlines in creating SPO-oriented intelligent flight systems to give captains adequate support for assuring safer air transportation.

关键词： Aviation engineering Single pilot operations Behaviour changes Eye tracker Electroencephalogram

Status quo and factors of depression and anxiety in patients with non-muscle invasive bladder cancer after plasma electrocision

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World Journal of Psychiatry 2024年第6期14卷 822-828页

作者： Bing Lu Meng Ding Hong-Bo Xu chun-yin Yan Department of Urology Suzhou Dushu Lake HospitalSuzhou 215000Jiangsu ProvinceChina Department of Urology The First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

BACKGROUND Bladder cancer is a type of cancer with a high incidence in *** electrosurgery(PES)is often used in the treatment of bladder *** complications often cause depression and anxiety in patients after *** To investigate the current state of depression and anxiety after PES in patients with non-muscle-invasive bladder cancer and analyze the factors affecting *** A retrospective study was conducted to compare the baseline data of patients by collecting their medical history and grouping them according to their mental status into negative and normal *** regression analysis was used to explore the risk factors affecting the occurrence of anxiety and depression after surgery in patients with bladder *** Comparative analyses of baseline differences showed that the patients in the negative and normal groups differed in terms of their first surgery,economic status,educational level,and marital status.A logistic regression analysis showed that it affected the occurrence of anxiety in patients with bladder cancer,and the results showed that whether the risk factors were whether or not it was the first surgery,monthly income between 3000 and 3000-6000,secondary or junior high school education level,single,divorced,and widowed *** The risk factors affecting the onset of anxiety and depression in bladder cancer patients after PES are the number of surgeries,economic status,level of education,and marital *** study provides a reference for the clinical treatment and prognosis of bladder cancer patients in the future.

关键词： Bladder cancer Anxiety Depression Analysis of influencing factors Plasma electrocision

Quasi-two dimensional Ruddlesden−Popper halide perovskites for laser applications

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Frontiers of physics 2024年第2期19卷 53-71页

作者： Kun Chen Qianpeng Zhang yin Liang Jiepeng Song chun Li Shi Chen Fang Li Qing Zhang School of Mechanical and Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China School of Materials Science and Engineering Peking UniversityBeijing 100871China Institute of Applied Physics and Materials Engineering Macao UniversityMacao 999078China

Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical *** review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and *** materials,structures and fabrications are introduced in the first ***,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface ***,the research progresses on lasing devices are summarized and several types of lasers including VCSEL,DFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are *** last,the challenges and perspectives would be provided.

关键词： two-dimensional materials metal halide perovskite Ruddlesden−Popper halide perovskites lasing emission

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong chun-yin Zhou Zi-Long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science