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Free vibration analysis of functionally graded material beams based on Levinson beam theory

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Applied Mathematics and Mechanics(English Edition) 2016年第7期37卷 861-878页

作者： xuan wang Shirong LI School of Hydraulic Energy and Power Engineering Yangzhou University School of Civil Science and Engineering Yangzhou University

Free vibration response of functionally graded material （FGM） beams is studied based on the Levinson beam theory （LBT）. Equations of motion of an FGM beam are derived by directly integrating the stress-form equations of elasticity along the beam depth with the inertial resultant forces related to the included coupling and higherorder shear strain. Assuming harmonic response, governing equations of the free vibration of the FGM beam are reduced to a standard system of second-order ordinary differential equations associated with boundary conditions in terms of shape functions related to axial and transverse displacements and the rotational angle. By a shooting method to solve the two-point boundary value problem of the three coupled ordinary differential equations, free vibration response of thick FGM beams is obtained numerically. Particularly, for a beam with simply supported edges, the natural frequency of an FGM Levinson beam is analytically derived in terms of the natural frequency of a corresponding homogenous Euler-Bernoulli beam. As the material properties are assumed to vary through the depth according to the power-law functions, the numerical results of frequencies are presented to examine the effects of the material gradient parameter, the length-to-depth ratio, and the boundary conditions on the vibration response.

关键词： functionally graded material (FGM) beam Levinson beam theory (LBT),free vibration shooting method natural frequency

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智能机器人在基层慢性病管理中的应用与挑战

中国全科医学 2025年第1期28卷 7-12,19页

作者：张璇张飞李铭麟王佳贺中国医科大学附属盛京医院全科医学科辽宁省沈阳市110000

全球慢性病患病率不断上升,给社会的发展和个人健康带来重大挑战。管理慢性病需要长期治疗和监测,对患者的生活方式提出了一定要求。随着人口老龄化和人们生活方式的改变,慢性病防控正变得越发重要。近年来,随着医疗卫生领域科技创新向... 详细信息

全球慢性病患病率不断上升,给社会的发展和个人健康带来重大挑战。管理慢性病需要长期治疗和监测,对患者的生活方式提出了一定要求。随着人口老龄化和人们生活方式的改变,慢性病防控正变得越发重要。近年来,随着医疗卫生领域科技创新向纵深发展,借助人工智能的智能机器人在医疗领域的应用也逐渐成为国家重要战略方向之一,传统的慢性病管理方法过于依赖医生和患者之间的线下交流,导致医生无法与患者保持长期且有效的沟通和随访,患者病情出现变化时医生可能无法及时发现和监测。此外,传统的慢性病管理方法通常是一种通用化的方法,无法充分考量到每位患者的个体差异。鉴于传统慢性病管理方法的局限性,本文提倡利用智能机器人提供更便捷高效的基层服务。本文认为,通过个性化健康管理方案、辅助医疗诊断、定时提醒服药等功能,使智能机器人能够致力于改善患者生活质量、减轻医疗资源压力,从而推动全球智能化医疗管理的发展。

关键词：智能机器人初级保健慢性病健康管理人工智能健康大数据

Bonding Interface Imaging and Shear Strength Prediction by Ultrasound1

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Chinese Physics Letters 2010年第6期27卷 118-121页

作者： LI Yong-An MAO Jie LI ming-xuan wang Xiao-Min AN Zhi-Wu ZHUANG Qiao State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190

The propagation of a longitudinal ultrasonic wave normally incident upon an adhesively bonded structure is stud- ied. The structure consists of adherend and adhesive layers with finite thickness. Interfaces between adherend and adhesive are regarded as distributed springs. Theoretical and experimental results show that resonant frequencies of the bonded structure vary sensitively with the interface stiffness constants and adhesive thickness, and these interface characteristics are inversed by the simulation annealing （SA） method. Furthermore, the distribution image of interface stiffnesses is compared with the state of fracture interface, and quantitative prediction of shear strength is achieved based on the distribution of interface stiffnesses and adhesive thicknesses by using a back- propagation neutral network. The average relative error of the shear strength from prediction to real value is 10.7%.

关键词： Ultrasonics Fractures Waves Adhesives Ultrasound imaging Numerical simulations

A review of energy and environment electrocatalysis based on high-index faceted nanocrystals

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Rare Metals 2021年第12期40卷 3406-3441页

作者： Yun-Rui Li ming-xuan Li Shu-Na Li Yu-Jie Liu Juan Chen Yao wang State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and EnvironmentChina University of PetroleumBeijing 102249China Department of Chemistry Tsinghua UniversityBeijing 100084China

Today,nanocrystals enclosed by high-index facets(HIFs)are attracting widely attentions of researchers due to their tremendous potential in the field of catalysis,especially in electrocatalysis,such as electro-oxidation of small organic molecule(such as formic acid,methanol,and ethanol),oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(OER).However,the practical applications of nanocrystals enclosed by HIFs still face many limitations in preparations of advanced electrocatalysts,including preparation strategy,limited life-time and *** development of advanced electrocatalysts enclosed with HIFs is crucial for solving these problems if the large-scale application of them is to be ***,we firstly detailedly demonstrate the identification methods of nanocrystals enclosed by HIFs,and then preparation strategies are elaborated in detail in this *** advanced nanocrystals enclosed by HIFs in electrocatalytic application are also summarized and we present representative achievements to further reveal the relationship of excellent electrocatalytic performance and nanocrystals with ***,we predict the remaining challenges and present our perspectives with regards of design strategies of improving electrocatalytic performance of Ptbased catalysts in the future.

关键词： Nanocrystals with high-index facets High surface free energy Electrocatalytic performance Water splitting Fuel cell

Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)

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Zoological Research 2024年第2期45卷 329-340页

作者： Shao-xuan Wu Qi-Fan Zeng Wen-Tao Han Meng-Ya wang Hui Ding ming-xuan Teng ming-Yi wang Pei-Yu Li Xin Gao Zhen-Min Bao Bo wang Jing-Jie Hu MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life Sciences/Key Laboratory of Tropical Aquatic Germplasm of Hainan ProvinceSanya Oceanographic InstitutionOcean University of ChinaQingdaoShandong/SanyaHainan 266100/572025China Hainan Seed Industry Laboratory SanyaHainan 572025China Southern Marine Science and Engineer Guangdong Laboratory GuangzhouGuangdong 511458China

The leopard coral grouper(Plectropomus leopardus)is a species of significant economic *** artificial cultivation of *** has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic *** this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct ***,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic ***,four of these clusters exhibited pronounced genetic differentiation compared with the other *** identify potentially advantageous loci for ***,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four *** these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to *** achievement holds promise for enabling high-quality,***,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell ***,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding *** findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting ***.

关键词： Plectropomus leopardus Whole-genome resequencing Growth Haplotype reference panel Single nucleotide polymorphisms

Generalization ability of a CNNγ-ray localization model for radiation imaging

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Nuclear Science and Techniques 2023年第12期34卷 53-65页

作者： Wei Lu Hai‑Wei Zhang ming‑Zhe Liu Hao‑xuan Li Xian‑Guo Tuo Lei wang Chengdu University of Technology Chengdu 610059China Sichuan University of Science and Engineering Zigong 643000China

Inγ-ray imaging,localization of theγ-ray interaction in the scintillator is *** neural network(CNN)techniques are highly promising for improvingγ-ray *** study evaluated the generalization capabilities of a CNN localization model with respect to theγ-ray energy and thickness of the *** model maintained a high positional linearity(PL)and spatial resolution for ray energies between 59 and 1460 *** PL at the incident surface of the detector was 0.99,and the resolution of the central incident point source ranged between 0.52 and 1.19 *** modified uniform redundant array(MURA)imaging systems using a thick crystal,the CNNγ-ray localization model significantly improved the useful field-of-view(UFOV)from 60.32 to 93.44%compared to the classical centroid localization ***,the signal-to-noise ratio of the reconstructed images increased from 0.95 to 5.63.

关键词： γ-Ray imaging γ-Ray localization model Convolutional neural network Spatial resolution

Improvement and Application of Acute Blood Stasis Rat Model Aligned with the 3Rs (Reduction, Refinement and Replacement) of Humane Animal Experimentation

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Chinese Journal of Integrative Medicine 2020年第4期26卷 292-298页

作者： HUANG Shuai XU Feng wang Yin-ye SHANG ming-ying wang Chao-qun wang xuan CAI Shao-qing State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing(100191)China Hubei Engineering Research Center of Viral Vector Wuhan University of BioengineeringWuhan(430415)China Department of Molecular and Cellular Pharmacology School of Pharmaceutical SciencesPeking UniversityBeijing(100191)China Division of Pharmaceutical Analysis School of Pharmaceutical SciencesPeking UniversityBeijing(100191)China

Objective:To establish a novel cardiocentesis method for withdrawing venous blood from the right atrium,and to improve an acute blood stasis rat model using an ice bath and epinephrine hydrochloride(Epi)while considering the 3Rs(reduction,refinement,and replacement)of humane animal ***:An acute blood stasis model was established in male Sprague-Dawley rats by subcutaneous injection(s.c.)Epi(1.2mg/kg)administration at 0h,followed by a 5-min exposure to an ice-bath at 2h and *** administration at *** rats received physiological *** were fasted overnight and treated with Angelicae Sinensis Lateralis Radix(ASLR)and Pheretima the following *** blood was collected using our novel cardiocentesis method and used to test whole blood viscosity(WBV),prothrombin time(PT),activated partial thromboplastin time(APTT),and fibrinogen(FIB)***:The rats survived the novel cardiocentesis technique;WBV value returned to normal while hematological parameters such as hemoglobin level and red blood cell count were restored to>94%of the corresponding values in normal rats following a 14-day ***(1.2 mg/kg,s.c.)combined with a 5-min exposure to the ice bath replicated the acute blood stasis rat model and was associated with the highest WBV *** rats showing acute blood stasis,ASLR treatment[4g/(kg-d)for 8 days]decreased WBV by 9.98%,11.09%,9.34%,9.00%,7.66%,and 7.03%(P<0.05),while Pheretima treatment[2.6g/(kg?d),for 8 days]decreased WBV by 25.49%,25.94%,16.28%,17.76%,11.07%,and 7.89%(P<0.01)at shear rates of 1,3,10,30,100,and 180 s'1,***,Pheretima treatment increased APTT significantly(P<0.01).Conclusions:We presented a stable,reproducible,and improved acute blood stasis rat model,which could be applied to screen drugs for promoting blood circulation and eliminating blood stasis.

关键词： acute blood stasis rat model cardiocentesis whole blood viscosity coagulation parameters Angelicae Sinensis Lateralis Radix Pheretima Chinese medicine syndrome

Seismic responses of slopes with different angles in coral sand

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Journal of Mountain Science 2021年第9期18卷 2475-2485页

作者： ZHANG Yan-ling DING xuan-ming CHEN Zhi-xiong WU Qi wang Cheng-long College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China

This paper investigates the seismic responses of slopes in coral sand taken from a reef island in the South China Sea.A series of shaking table model tests were conducted to explore the responses of soil acceleration,excess pore pressure,and slope displacement for three slope angles(5°,10°,and 15°).The results show that the excess pore pressure ratio of the slope decreases due to an increase in the initial shear stress when the slope angle *** acceleration response of the soil increases with the increase of the slope *** slope displacement presents substantial increments as the excess pore pressure ratio *** addition,the lateral movement,and slope settlement present substantial increments as the slope angle *** liquefaction is observed under a dynamic excitation of 0.2 g in the coral sand *** a dynamic excitation of 0.4 g,the site liquefies quickly,the acceleration amplification factor decreases,and the lateral movement and the settlement of the slope surface both increase compared with that under 0.2 g *** the slope with an angle of 15°at 0.4 g,the flow distance of the sand strip increase by 289.47%compared with that in the 5°*** lateral movement of the slope surface near the water level line is substantially larger than that away from the water *** largest settlement is observed near the middle section of the slope(below the water level)under a dynamic excitation of 0.2 *** contrast,the largest settlement under a dynamic excitation of 0.4 g occurs at the top of the slope.

关键词： Coral sand Slope angle Shaking table tests Seismic response Liquefaction

The Role of Ozone Depletion in the Lack of Cooling in the Antarctic Upper Stratosphere during Austral Winter

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Advances in Atmospheric Sciences 2023年第4期40卷 619-633页

作者： xuan MA Lei wang Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Shanghai Qi Zhi Institute Shanghai 200232China Big Data Institute for Carbon Emission and Environmental Pollution Fudan UniversityShanghai 200438China Lamont-Doherty Earth Observatory Columbia UniversityPalisadesNew York 10964USA

Temperature trends in the upper stratosphere are investigated using satellite measurements from Stratospheric Sounding Unit(SSU)outputs and simulations from chemistry-climate models(CCMs)and the Coupled Model Intercomparison Project Phase 6(CMIP6).Observational evidence shows a lack of cooling in the Antarctic,in contrast to strong cooling at other latitudes,during austral winter over *** of CCM simulations for a longer period of1961-97 also shows a significant contrast in the upper stratospheric temperature trends between the Antarctic and lower *** from two sets of model integrations with fixed ozone-depleting substances(ODSs)and fixed greenhouse gases(GHGs)at their 1960 levels suggest that the ODSs have made a major contribution to the lack of cooling in the Antarctic upper *** from CMIP6 simulations with prescribed GHGs and ozone confirm that changes in the dynamical processes associated with observed ozone depletion are largely responsible for the lack of cooling in the Antarctic upper *** lack of cooling is found to be dynamically induced through increased upward wave activity into the upper stratosphere,which is attributed mainly to ODSs ***,the radiative cooling caused by the ozone depletion results in a stronger meridional temperature gradient between middle and high latitudes in the upper stratosphere,allowing more planetary waves propagating upward to warm the Antarctic upper *** findings improve our understanding of the chemistry-climate coupling in the southern upper stratosphere.

关键词： Antarctic stratosphere temperature trends ozone wave activity