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激光复合加工硬脆性材料研究进展综述

机械工程学报 2024年第9期60卷 168-188页

作者：温秋玲杨野黄辉黄国钦胡中伟陈金鸿汪晖吴贤华侨大学制造工程研究院厦门361021 高性能工具全国重点实验室(华侨大学) 厦门361021 华侨大学机电及自动化学院厦门361021

玻璃、半导体、蓝宝石、陶瓷和硬质合金等硬脆性材料被广泛应用于建筑、生物医疗、航空航天、集成电路、新能源、光电显示、轨道交通、海洋等领域。但是其高硬度、大脆性、高耐磨性和耐腐蚀等特性也给它们的加工带来巨大挑战。目前,机... 详细信息

玻璃、半导体、蓝宝石、陶瓷和硬质合金等硬脆性材料被广泛应用于建筑、生物医疗、航空航天、集成电路、新能源、光电显示、轨道交通、海洋等领域。但是其高硬度、大脆性、高耐磨性和耐腐蚀等特性也给它们的加工带来巨大挑战。目前,机械加工、离子束加工、化学蚀刻、激光加工等方式是加工硬脆性材料的主要方法。但是这些加工方式依然存在加工效率和加工质量不可兼得的瓶颈问题。为此,研究人员提出了将激光加工和其他加工方式结合起来的复合加工方法,旨在实现硬脆性材料的高质量和高效率加工。概述了主流的基于激光复合的硬脆材料加工方法,主要包括其他方式辅助激光加工、激光辅助其他方式加工、激光辅助激光加工;重点阐述了这些激光复合加工技术的加工原理、研究现状和加工效果;总结了不同激光复合加工方法的优势、局限性和应用场景,最后对激光复合加工硬脆性材料的未来发展趋势提出了展望。

关键词：激光复合加工硬脆性材料加工效率加工质量微结构

Thermal Analysis of Turbine Blades with Thermal Barrier Coatings Using Virtual Wall Thickness Method

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Computer Modeling in Engineering & Sciences 2023年第2期134卷 1219-1236页

作者： Linchuan Liu Jian Wu zhongwei hu Xiaochao Jin Pin Lu Tao Zhang Xueling Fan Joint Research Center for Extreme Environment and Protection Technology School ofAerospace EngineeringXi’an Jiaotong UniversityXi’an710049China AEEC Sichuan Gas Turbine Establishment Chengdu610500China

Avirtual wall thicknessmethod is developed to simulate the temperature field of turbine bladeswith thermal barrier coatings(TBCs),to simplify the modeling process and improve the calculation *** results show that the virtualwall thickness method can improve themesh quality by 20%,reduce the number ofmeshes by 76.7%and save the calculation time by 35.5%,compared with the traditional real wall thickness *** average calculation error of the two methods is between 0.21%and 0.93%.Furthermore,the temperature at the blade leading edge is the highest and the average temperature of the blade pressure surface is higher than that of the suction surface under a certain service *** blade surface temperature presents a high temperature at both ends and a low temperature in themiddle height when the temperature of incoming gas is uniformand *** thermal insulation effect of TBCs is the worst near the air film hole,and the best at the blade leading *** to the calculated temperature field of the substrate-coating system,the highest thermal insulation temperature of the TC layer is 172.01 K,and the thermal insulation proportions of TC,TGO and BC are 93.55%,1.54%and 4.91%,respectively.

关键词： Turbine blade thermal analysis thermal barrier coatings finite element method virtual wall thickness

Tensor-Based Joint Channel Estimation and Symbol Det ection for AF MIMO Relay Networks

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 88-96页

作者： LIN Heyun YUAN Chaowei DU Jianhe hu zhongwei School of Information and Communication Engineering.Communication University of China Beijing 100024China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

A study on the joint channel and symbol estimation issue is provided for two hop relay networks which employ the amplify-and-forward(AF)relaying *** encoding scheme at the source node introduces the time-domain spreading with a time-varying linear constellation ***,a set of amplifying factors matrices is utilized by the relays to amplify and forward the received data to the *** received signal at the destination can be construe ted as a fourth-order tensor model,which is referred to as the nested parallel factor(PARAFAC)*** then,we present a novel Levenberg-Marquardt(LM)algorithm based on this tensor *** proposed method does not require complex signal processing at the relay,which effectively reduces the burden of *** a semi-blind method,which does not require the pilot signal,the proposed receiver can jointly recover the channels and information ***,the proposed semi-blind receiver is robust as it can work in different wireless channel *** are conducted to demonstrate the efficiency of the proposed semi-blind approach.

关键词： fourth-order tensor semi-blind receiver Levenberg-Marquardt algorithm nested parallel factor model amplify-and-forward

Coronal structure and brightness profile of the total solar eclipse on August 1,2008

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Chinese Science Bulletin 2009年第16期54卷 2905-2908页

作者： ZHAO HaiBin LIN QiSheng CHEN YiPing JIN Sheng GUAN ZhenBiao hu zhongwei Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Lulin Observatory Taoyuan 32054 Taiwan China Department of Astronomy Nanjing University Nanjing 210008 China

Solar corona is the outermost part of the solar atmosphere. Coronal activities influence space environment between the Sun and the Earth, space weather and the Earth itself. The total solar eclipse (TSE) is the best opportunity to observe the solar corona on ground. During the TSE 2008, a series of images of the corona and partial eclipse of solar disk were obtained using telescope and CCD camera. After image processing, preliminary results of coronal structure are given, and radial brightness profiles of the corona in directions of pole and equator of the Sun are measured. Though in solar activity minimum, the shape and structure of the corona are not symmetry. The equatorial regions are more extent than the polar one, and there are also larger differences between the east and west equatorial regions and between the south and north polar regions. Coronal streamers on east side of the equator, particularly the largest one in east-south direction, are very obvious. The coronal plume in south polar region consists of more polar rays than that in north polar region. These structures are also shown in other observations and data of SOHO. The radial brightness profiles in directions of pole and equator are similar to those of the Van de hulst model in solar minimum, but there are a few differences due to coronal activity, which is shown in the isophote map of the corona.

关键词：太阳日冕配置文件日全食结构赤道地区太阳能利用北极地区太阳大气

Battery pack capacity estimation for electric vehicles based on enhanced machine learning and field data

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Journal of Energy Chemistry 2024年第5期92卷 605-618页

作者： Qingguang Qi Wenxue Liu zhongwei Deng Jinwen Li Ziyou Song Xiaosong hu College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Department of Mechanical Engineering National University of SingaporeSingapore 117575Singapore

Accurate capacity estimation is of great importance for the reliable state monitoring,timely maintenance,and second-life utilization of lithium-ion *** numerous works on battery capacity estimation using laboratory datasets,most of them are applied to battery cells and lack satisfactory fidelity when extended to real-world electric vehicle(EV)battery *** challenges intensify for large-sized EV battery packs,where unpredictable operating profiles and low-quality data acquisition hinder precise capacity *** fill the gap,this study introduces a novel data-driven battery pack capacity estimation method grounded in field *** proposed approach begins by determining labeled capacity through an innovative combination of the inverse ampere-hour integral,open circuit voltage-based,and resistance-based correction ***,multiple health features are extracted from incremental capacity curves,voltage curves,equivalent circuit model parameters,and operating temperature to thoroughly characterize battery aging behavior.A feature selection procedure is performed to determine the optimal feature set based on the Pearson correlation ***,a convolutional neural network and bidirectional gated recurrent unit,enhanced by an attention mechanism,are employed to estimate the battery pack capacity in real-world EV ***,the proposed method is validated with a field dataset from two EVs,covering approximately 35,000 *** results demonstrate that the proposed method exhibits better estimation performance with an error of less than 1.1%compared to existing *** work shows great potential for accurate large-sized EV battery pack capacity estimation based on field data,which provides significant insights into reliable labeled capacity calculation,effective features extraction,and machine learning-enabled health diagnosis.

关键词： Electricvehicle Lithium-ion battery pack Capacity estimation Machine learning Field data

Significantly reduced abilities to cross-neutralize SARS-CoV-2 variants by sera from convalescent COVID-19 patients infected by Delta or early strains

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Cellular & Molecular Immunology 2021年第11期18卷 2560-2562页

作者： Ting Pan zhongwei hu Fengyu hu Yiwen Zhang Bingfeng Liu Changwen Ke Qiumin She Xin He Xiaoping Tang hui Zhang Institute of human Virology Key Laboratory of Tropical Disease Control of Ministry EducationGuangdong Engineering Research Center for Antimicrobial Agent and ImmunotechnologyZhongshan School of MedicineSun Yat-sen UniversityGuangzhouGuangdongChina Center for Infection and Immunity Study School of MedicineShenzhen Campus of Sun Yat-sen UniversityShenzhenGuangdongChina Guangzhou Eighth People’s Hospital Guangzhou Medical UniversityGuangzhouGuangdongChina Guangdong Provincial Center for Disease Control and Prevention GuangzhouGuangdongChina National Guangzhou Laboratory Bio-IslandGuangzhouGuangdongChina

The worldwide pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in more than 4.5 million *** coronaviruses have a proofreading mechanism to maintain the stability of their long genomic RNAs,mutations emerge continuously,and new variants conferring advantages rapidly become the dominant lineages[1].Strategies to fight the COVID-19 pandemic using either vaccines or nonpharmaceutical interventions have specifically been threatened by the emergence of SARS-CoV-2 variants of concern(VOCs)[2].

关键词： acute respiratory neutral

Rapid health estimation of in-service battery packs based on limited labels and domain adaptation

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Journal of Energy Chemistry 2024年第2期89卷 345-354,I0009页

作者： zhongwei Deng Le Xu Hongao Liu Xiaosong hu Bing Wang Jingjing Zhou School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina School of Sustainability Stanford UniversityStanfordCA 94305USA College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China China Automotive Engineering Research Institute Co.Ltd. Chongqing 401122China

For large-scale in-service electric vehicles(EVs)that undergo potential maintenance,second-hand transactions,and retirement,it is crucial to rapidly evaluate the health status of their battery ***,existing methods often rely on lengthy battery charging/discharging data or extensive training samples,which hinders their implementation in practical *** address this issue,a rapid health estimation method based on short-time charging data and limited labels for in-service battery packs is proposed in this ***,a digital twin of battery pack is established to emulate its dynamic behavior across various aging levels and inconsistency ***,increment capacity sequences(△Q)within a short voltage span are extracted from charging process to indicate battery ***,data-driven models based on deep convolutional neural network(DCNN)are constructed to estimate battery state of health(SOH),where the synthetic data is employed to pre-train the models,and transfer learning strategies by using fine-tuning and domain adaptation are utilized to enhance the model ***,field data of 10 EVs exhibiting different SOHs are used to verify the proposed *** using the△Q with 100 m V voltage change,the SOH of battery packs can be accurately estimated with an error around 3.2%.

关键词： Lithium-ion battery Electric vehicles Health estimation Feature extraction Convolutional neural network Domain adapatation

Bioinspired coacervate-based bioinks for construction of multiscale tissue engineering scaffolds

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Nano Research 2024年第9期17卷 8209-8219页

作者： zhongwei Guo Shiqiang Zhang Yilin Guo Jingjing Xia Xiao Wu Hao hu Rongcheng hu Fangli huang Qiulei Gao Chun Liu Jingjiang Qiu Wei Sun School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Department of Mechanical Engineering and Mechanics Tsinghua UniversityBeijing 100084China Precision Medicine Institute Guangdong Provincial Key Laboratory of Orthopedics and TraumatologyThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104USA

Engineering hydrogels that resemble biological tissues of various lengths via conventional fabrication techniques remains ***-dimensional(3D)bioprinting has emerged as an advanced approach for constructing complex biomimetic 3D architectures,which are currently restricted by the limited number of available bioinks with high printability,biomimicry,biocompatibility,and proper mechanical *** by ubiquitous coacervation phenomena in biology,we present a unique mineral-biopolymer coacervation strategy that enables the hierarchical assembly of nanoclay and recombinant human collagen(RHC).This system was observed to undergo a coacervation transition(liquid‒liquid phase separation)*** formed dense phase separated from its supernatant is the coacervate of clay-RHC-rich complexes,where polymer chains are sandwiched between silicate *** dynamics simulation was first used to verify and explore the coacervation ***,the coacervates were demonstrated to be potential bioinks that exhibited excellent self-supporting and shear-thinning viscoelastic *** extrusion-based printing,the versatility of the bioink was demonstrated by reconstructing the key features of several biological tissues,including multilayered lattice,vascular,nose,and ear-like structures,without the need for precrosslinking operations or support ***,the printed scaffolds were cytocompatible,elicited minimal inflammatory responses,and promoted bone regeneration in calvarial defects.

关键词： bioinks coacervation mineral-biopolymer nanoclay tissue engineering scaffold

Characteristics of SARS-CoV-2 Delta variant-infected individuals with intermittently positive retest viral RNA after discharge

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National Science Review 2022年第10期9卷 63-66页

作者： Lu Li Jingyan Tang Zhiwei Xie Qingxin Gan Guofang Tang zhongwei hu huimin Zeng Jingrong Shi Jiaojiao Li Yan Li Changwen Ke Min Kang Dan Liang huan Lu Yuwei Tong Xilong Deng Jinxin Liu Hongzhou Lu Fuxiang Wang Fengyu hu Feng Li Nanshan Zhong Xiaoping Tang Guangzhou Eighth People's Hospital Guangzhou Medical University Guangdong Provincial Center for Disease Control and Prevention The Third People's Hospital of Shenzhen Guangzhou Laboratory National Clinical Research Center for Respiratory Diseases of First Affiliated Hospital Guangzhou Medical University

SARS-CoV-2-infected patients will be discharged when viral ribonucleic acid(RNA) is consecutively negative at least twice over a 24-h ***,we have demonstrated that positive retest viral RNA,a particular clinical phenomenon initially observed in discharged SARS-CoV-2-infected patients in early 2020 [1,2],is the occasional reoccurrence of Polymerase Chain Reaction (PCR)-detectable viral RNA but not reinfection [3].Unfortunately,workable strategies to effectively discriminate against individuals likely to have positive retest viral RNA are still ***,for safety concerns,a mandatory minimum of 14-day quarantine in hospitals or hotels had been strictly applied for discharged *** that the Delta Variant of Concern (VOC),the dominant SARS-CoV-2 strain in 2021,

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