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Investigation of stress distribution and damage behavior caused by forced installation of a composite bolted joint with a hole-location error

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Chinese Journal of Aeronautics 2024年第1期37卷 201-217页

作者： Chinan LIU Yuan LI yi cheng An’an ZHAO kunpeng DU Yue SHI Ximing LI Hui cheng School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aircraft Industry Group Company LTD Xi’an 710089China

In this paper,the influence of forced installation caused by a hole-location error on the 3D stress distribution and damage of a composite bolted joint is *** analytical model of stress distributed on composite holes is promoted,in view of non-uniform extrusion caused by forced *** first,non-uniform extrusion of the hole edge caused by forced installation is *** to the contact state,expression of hole deformation is ***,based on Hertz theory,the maximum extrusion load is obtained with help of deformation *** constructing an elastic foundation beam model,3D stress distributed on a hole could be analyzed according to the extrusion ***,stress distribution predicted by the above analytical method is compared with that provided by FE considering composite ***,a forced installation experiment is carried out to analyze the damage distribution of the *** show that a central-symmetrically distributed stress is introduced by the hole-location *** an increment of the error,strength of composite decreases due to extrusion ***,stress presents a concave distribution on the *** the hole-location error exceeding 3%,stress decreases gradually due to failure of *** of holes does not exhibit a centrosymmetric *** damage is mainly distributed on the entrance of the hole at the lower sheet.

关键词： Hole-location error Composite joint Forced installation Stress distribution Damage

Prevalence of hypertension and its associations with body composition across Chinese and American children and adolescents

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World Journal of Pediatrics 2024年第4期20卷 392-403页

作者： Li-Wang Gao yi-Wen Huang Hong cheng Xi Wang Hong-Bo Dong Pei Xiao yin-kun Yan Xin-ying Shan Xiao-Yuan Zhao Jie Mi Center for Non-Communicable Disease Management Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthNo.56 Nanlishi RoadXicheng DistrictBeijing100045China Department of Epidemiology Capital Institute of PediatricsNo.2 Yabao RoadChaoyang DistrictBeijing100020China Key Laboratory of Major Diseases in Children Ministry of EducationBeijingChina

Background The age of onset of hypertension(HTN)is decreasing,and obesity is a significant risk *** prevalence and racial disparities in pediatric HTN and the association between body composition and blood pressure are insufficiently *** study aimed to evaluate the prevalence of HTN in Chinese and American children and adolescents and to assess the relationship between various body composition indices and *** Seven thousand,five hundred and seventy-three Chinese and 6239 American children and adolescents aged 8–18 years from the 2013–2015 China Child and Adolescent Cardiovascular Health study and the 2011–2018 National Health and Nutrition Examination Surveys were *** pressure and body composition(fat and muscle)were measured by trained *** crude prevalence and age-standardized prevalence rate(ASPR)of primary HTN and its subtypes[isolated systolic hypertension(ISH)and isolated diastolic hypertension(IDH)]were calculated based on 2017 American Academy of Pediatrics ***-adjusted linear regression coefficients and odds ratios(ORs)were calculated to assess the associations of body composition indicators with HTN,ISH and *** The ASPR of HTN was 18.5%in China(CN)and 4.6%in the United States(US),whereas the obesity prevalence was 7.4%and 18.6%,and the population attributable risk of HTN caused by overweight and obesity was higher in the US than in *** fat mass,muscle mass and body fat percentage mass were associated with a higher risk of HTN in both *** percent of muscle body mass had a protective effect on HTN and ISH in both countries[HTN(CN:OR=0.83,95%CI=0.78–0.88;US:OR=0.72,95%CI=0.64–0.81);ISH(CN:OR=0.87,95%CI=0.80–0.94;US:OR=0.71,95%CI=0.62–0.81)],and the protective effect was more common among children and adolescents with high levels of physical *** The burden of HTN in Chinese children and adolescents was substantial and much greater than that in the US,and th

关键词： Body composition Children and adolescents China Child and Adolescent Cardiovascular Health Hypertension National Health and Nutrition Examination Surveys

Shape optimisation of basin insulator for DC gas insulated switchgear/gas insulated transmission lines based on artificial bee colony algorithm

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High Voltage 2024年第2期9卷 275-286页

作者： yi Luo Shiyi Mao Ju Tang Zijun Pan cheng Pan State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current(HVDC)gas insulated switchgears(GIS)and gas insulated trans-mission lines(GIL),which restricts the development and application of extra/ultra high-voltage(EHV/UHV)*** surface charge distribution and anti-flashover performance are closely related to the insulator *** obtain the optimal basin insulator,a shape optimisation model based on artificial bee colony algorithm was established,and the minimisation objective functions based on capacitive(initial)electric field distribution and resistive(steady-state)electric field distribution were respectively *** optimisation results of the two objective functions were calculated,and the electric field and charge distribution on the surface of the insulator before and after optimisation were evaluated and compared using the simulation *** results indicated that the optimisation based on the capacitive electric field can significantly inhibit the surface charge accumulation,and the optimised insulator can significantly reduce the surface normal electric field and make the distribution of the tangential electric field more uniform,and the maximum tangential electric field can be reduced by 10%;the optimisation based on resistive electric field can achieve similar results,but requires more computational *** on the results,the‘anti-charge’basin insulator structure suitable for the DC field was given.

关键词： insulator artificial charge

Exercise-induced adaptation of neurons in the vertebrate locomotor system

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Journal of Sport and Health Science 2024年第2期13卷 160-171页

作者： Yue Dai yi cheng Renkai Ge Ke Chen Liming Yang Key Lab of Adolescent Health Assessment and Exercise Intervention of Ministry of Education College of Physical Education and Health CareEast China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Multidimensional Information Processing School of Communication and Electronic EngineeringEast China Normal UniversityShanghai 200241China School of Physical Education and Health Care East China Jiaotong UniversityNanchang 330013China Key Laboratory of High Confidence Software Technologies of Ministry of Education School of Computer SciencePeking UniversityBeijing 100871China

Vertebrate neurons are highly dynamic cells that undergo several alterations in their functioning and physiologies in adaptation to various external *** particular,how these neurons respond to physical exercise has long been an area of active *** of the vertebrate locomotor system’s adaptability suggest multiple mechanisms are involved in the regulation of neuronal activity and properties during *** this brief review,we highlight recent results and insights from the field with a focus on the following mechanisms:(a)alterations in neuronal excitability during acute exercise;(b)alterations in neuronal excitability after chronic exercise;(c)exercise-induced changes in neuronal membrane properties via modulation of ion channel activity;(d)exercise-enhanced dendritic plasticity;and(e)exercise-induced alterations in neuronal gene expression and protein *** hope is to update the community with a cellular and molecular understanding of the recent mechanisms underlying the adaptability of the vertebrate locomotor system in response to both acute and chronic physical exercise.

关键词： Dendritic plasticity Excitability Exercise Ion channel modulation Neuron adaptation

Application of total keratometry in ten intraocular lens power calculation formulas in highly myopic eyes

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Eye and Vision 2024年第2期10卷 22-30页

作者： Ling Wei Kaiwen cheng Wenwen He Xiangjia Zhu yi Lu Department of Ophthalmology and Eye Institute Eye and ENT Hospital of Fudan UniversityShanghai 200031China Key Laboratory of Myopia(Fudan University)Key Laboratory of MyopiaShanghai Key Laboratory of Visual Impairment and Restoration National Health CommissionChinese Academy of Medical ScienceShanghai 200031China State Key Laboratory of Medical Neurobiology Fudan UniversityShanghai 200031China

Background:The accuracy of using total keratometry(TK)value in recent IOL power calculation formulas in highly myopic eyes remained ***:Highly myopic patients who underwent uneventful cataract surgery were prospectively enrolled in this prospective comparative *** one month postoperatively,standard deviation(SD)of the prediction errors(PEs),mean and median absolute error(MedAE)of 103 highly myopic eyes were back-calculated and compared among ten formulas,including XGboost,RBF 3.0,Kane,Barrett Universal II,Emmetropia Verifying Optical 2.0,Cooke K6,Haigis,SRK/T,and Wang-Koch modifications of Haigis and SRK/T formulas,using either TK or standard keratometry(K)***:In highly myopic eyes,despite good agreement between TK and K(P>0.05),larger differences between the two were associated with smaller central corneal thickness(P0.05),which both presented smaller MedAEs than others(all P0.05),and statistically larger percentages than the other eight formulas(P<0.05).Conclusions:Highly myopic eyes with thinner corneas tend to have larger differences between TK and *** XGboost enhancement calculator and RBF 3.0 formula using TK showed the most promising outcomes in highly myopic eyes.

关键词： High myopia Total keratometry Cataract surgery IOL power calculation

A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1424-1437页

作者： Quanbo Ge Yang cheng Hong Li Ziyi Ye yi Zhu Gang Yao School of Automation Nanjing University of Information Science&TechnologyJiangsu Provincial University Key Laboratory of Big Data Analysis and Intelligent SystemsNanjing University of Information Science&Technologyand the Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science&TechnologyNanjing 210044China School of Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China China Classification Society Nantong Office Nantong 226006China Chinese Flight Test Establishment Xi’an 710089China School of Mathematics Tsinghua UniversityBeijing 100084China School of Automation Nanjing University of Information Science&TechnologyNanjing 210044China Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China IEEE

For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity *** the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and *** com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment.

关键词： Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.

Microstructural characterization and mechanical properties of(TiC+TiB)/TA15 composites prepared by an in-situ synthesis method

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China Foundry 2024年第2期21卷 168-174页

作者： Zhi-yong Zhang Jiao-jiao cheng Jia-qi Xie Shi-bing Liu kun Shi Jun Zhao Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high *** this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting *** characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were *** revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and ***,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like *** increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature ***,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies

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Nuclear Science and Techniques 2024年第2期35卷 170-182页

作者： Gao-yi cheng Qian-Min Su Xi-Guang Cao Guo-Qiang Zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate *** urgently need solutions to the dilemma of traditional particle identification *** study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate *** intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 ***-based machine learning algorithms and deep learning algorithms *** show excellent performance and generalization *** additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is *** learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.

关键词： Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance

Conceptual design of a 714-MHz RFQ for compact proton injectors and development of a new tuning algorithm on its aluminium prototype

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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： yi-Xing Lu Wen-cheng Fang Yu-Sen Guo Zhen-Tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator *** RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this *** RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary *** develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a *** aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning ***,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning *** from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning