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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang pei-Da hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining equipment.Most active vibration-isolation systems(AVIS)have been developed based on static loads.When a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy deteriorates.To solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining conditions.Vibration-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were conducted.The experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load conditions.This design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Thermo-hydro-poro-mechanical responses of a reservoir-induced landslide tracked by high-resolution fiber optic sensing nerves

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1018-1032页

作者： Xiao Ye Hong-hu Zhu Gang Cheng hua-Fu pei Bin Shi Luca Schenato Alessandro Pasuto School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China School of Computer Science North China Institute of Science and Technology(National Safety Training Center of Coal Mines)Beijing101601China State Key Lab of Coastal and Offshore Engineering Department of Geotechnical EngineeringDalian University of TechnologyDalian116024China National Research Council-Research Institute for Geo-Hydrological Protection(CNR-IRPI) Padova35127Italy Department of Information Engineering University of PadovaPadova35131Italy

Thermo-poro-mechanical responses along sliding zone/surface have been extensively studied.However,it has not been recognized that the potential contribution of other crucial engineering geological interfaces beyond the slip surface to progressive failure.Here,we aim to investigate the subsurface multiphysics of reservoir landslides under two extreme hydrologic conditions(i.***.wet and dry),particularly within sliding masses.Based on ultra-weak fiber Bragg grating(UWFBG)technology,we employ specialpurpose fiber optic sensing cables that can be implanted into boreholes as“nerves of the Earth”to collect data on soil temperature,water content,pore water pressure,and strain.The Xinpu landslide in the middle reach of the Three Gorges Reservoir Area in China was selected as a case study to establish a paradigm for in situ thermo-hydro-poro-mechanical monitoring.These UWFBG-based sensing cables were vertically buried in a 31 m-deep borehole at the foot of the landslide,with a resolution of 1 m except for the pressure sensor.We reported field measurements covering the period 2021 and 2022 and produced the spatiotemporal profiles throughout the borehole.Results show that wet years are more likely to motivate landslide motions than dry years.The annual thermally active layer of the landslide has a critical depth of roughly 9 m and might move downward in warmer years.The dynamic groundwater table is located at depths of 9e15 m,where the peaked strain undergoes a periodical response of leap and withdrawal to annual hydrometeorological cycles.These interface behaviors may support the interpretation of the contribution of reservoir regulation to slope stability,allowing us to correlate them to local damage events and potential global destabilization.This paper also offers a natural framework for interpreting thermo-hydro-poro-mechanical signatures from creeping reservoir bank slopes,which may form the basis for a landslide monitoring and early warning system.

关键词： Reservoir landslide Thermo-hydro-poro-mechanical response Ultra-weak fiber bragg grating(UWFBG) subsurface evolution Engineering geological interface Geotechnical monitoring

Emergence of SARS and COVID-19 and preparedness for the next emerging disease X

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Frontiers of Medicine 2024年第1期18卷 1-18页

作者： Ben hu hua Guo Haorui Si Zhengli Shi CAS Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Severe acute respiratory syndrome(SARS)and Coronavirus disease 2019(COVID-19)are two human Coronavirus diseases emerging in this century,posing tremendous threats to public health and causing great loss to lives and economy.In this review,we retrospect the studies tracing the molecular evolution of SARS-CoV,and we sort out current research findings about the potential ancestor of SARS-CoV-2.Updated knowledge about SARS-CoV-2-like viruses found in wildlife,the animal susceptibility to SARS-CoV-2,as well as the interspecies transmission risk of SARS-related coronaviruses(SARSr-CoVs)are gathered here.Finally,we discuss the strategies of how to be prepared against future outbreaks of emerging or re-emerging coronaviruses.

关键词： SARS COVID-19 coronavirus

Privacy Preserving Algorithm for Spectrum Sensing in Cognitive Vehicle Networks

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Chinese Journal of Electronics 2024年第1期33卷 30-42页

作者： Hongning LI Tonghui hu Jiexiong CHEN Xiuqiang WU Qingqi pei Guangzhou Institute of Technology Xidian University Guangzhou CEPREI Shaanxi Key Laboratory of Blockchain and Secure Computing

The scarcity of spectrum resources fails to meet the increasing throughput demands of vehicular networks. There is an urgent need to maximize the utilization of spectrum bands in mobile networks. To ascertain the availability of spectrum bands, users should engage in wireless channel sensing and collaboration. However, spectrum sensing data always involves users’ privacy, such as their location. This paper first introduces sensing trajectory inference attack in cognitive vehicular networks and then proposes a data confusion-based privacy-preserving algorithm and a cryptonym array-based privacy-preserving aggregation scheme for spectrum sensing in cognitive vehicular networks. Unlike existing methods, the proposed schemes transmit confused data during the aggregation process. This deliberate obfuscation makes it almost impossible to infer users’ location from the transmitted data. The analysis demonstrates the resilience of the proposed schemes against sensing trajectory inference attack.

关键词： Location privacy preservation Cognitive radio network Cooperative spectrum sensing

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

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Journal of Energy Chemistry 2024年第8期95卷 712-722页

作者： Yan-Cheng hu Yingying Zhao Ning Li Jing-pei Cao School of Chemical Engineering and Technology China University of Mining and Technology School of Education Science Jiangsu Normal University CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon society. High-energy-density(HED) jet fuel, featuring unique fused/strained cycloalkanes, is of great significance for volume-limited military aircrafts, as their high density and combustion heat can extend flight duration and increase the payload. Therefore, the exploration of biomass-based routes towards HED fuel has drawn much attention over the past decade. Cycloaddition reaction features rapid construction of various carbocycles in an atom-and step-economical fashion. This elegant strategy has been widely applied in the manufacture of sustainable HED fuel. Here we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including [4+2], [2+2],[4+4], and [2+1] cycloadditions. Besides, the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10) are also compared. This review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

关键词： Biomass-based chemicals Catalysis Cycloaddition Cycloalkanes High-energy-density fuel

Severe pediatric COVID‑19:a review from the clinical and immunopathophysiological perspectives

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World Journal of Pediatrics 2024年第4期20卷 307-324页

作者： Yi‑Kan Sun Can Wang pei‑Quan Lin Lei hu Jing Ye Zhi‑Gang Gao Ru Lin Hao‑Min Li Qiang Shu Li‑Su huang Lin‑hua Tan Children's Hospital Zhejiang University School f MedicineHangzhou 310052China The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310030China Surgical Intensive Care Unit Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of General Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiopulmonary and Extracorporeal Life Support Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Clinical Data Center Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiac Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China National Clinical Research Center for Child Health Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Infectious Diseases Children’s HospitalZhejiang University School of MedicineHangzhou 310052China

Background Coronavirus disease 2019(COVID-19)tends to have mild presentations in children.However,severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times,meriting further attention from clinicians.Meanwhile,the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely understood.Data sources A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed,Embase,and Wanfang databases.Searched keywords included“COVID-19 in children”,“severe pediatric COVID-19”,and“critical illness in children with COVID-19”.Results Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated status.Acute respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations,while various forms of cardiovascular and neurological involvement may also be seen.Multiple immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways,whose dysregulation in severe and critical diseases translates into adverse clinical manifestations.Multisystem inflammatory syndrome in children(MIS-C),a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure,denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric immunity.Despite the considerable dissimilarities between the pediatric and adult immune systems,clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult guidelines.Conclusions Severe pediatric COVID-19 can affect multiple organ systems.The dysregulated immune pathways in severe COVID-19 shape the disease course,epitomize the vast functional diversity of the pediatric immune system and highlight the immun

关键词： Immunopathophysiology MIS-C Pediatric critical care Severe pediatric COVID-19

Encoding biological metaverse: Advancements and challenges in neural fields from macroscopic to microscopic

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The Innovation 2024年第3期5卷 30-32页

作者： Yantong Cai Wenbo hu Yao pei Hao Zhao Guangchuang Yu Dermatology Hospital Southern Medical UniversityGuangzhou 266003China Department of Bioinformatics School of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China Tencent AI Lab Shenzhen 518071China State Key Laboratory of Emerging Infectious Diseases School of Public HealthThe University of Hong KongHong Kong SARChina Laboratory of Data Discovery for Health(D24H) Hong Kong Science ParkHong Kong SARChina Institute for AI Industry Research Tsinghua UniversityBeijing 100000China

Neural fields can efficiently encode three-dimensional(3D)scenes,providing a bridge between two-dimensional(2D)images and virtual reality.This method becomes a trendsetter in bringing the metaverse into vivo life.It has initially captured the attention of macroscopic biology,as demonstrated by computed tomography and magnetic resonance imaging,which provide a 3D field of view for diagnostic biological images.Meanwhile,it has also opened up new research opportunities in microscopic imaging,such as achieving clearer de novo protein structure reconstructions.Introducing this method to the field of biology is particularly significant,as it is refining the approach to studying biological images.However,many biologists have yet to fully appreciate the distinctive meaning of neural fields in transforming 2D images into 3D perspectives.This article discusses the application of neural fields in both microscopic and macroscopic biological images and their practical uses in biomedicine,highlighting the broad prospects of neural fields in the future biological metaverse.We stand at the threshold of an exciting new era,where the advancements in neural field technology herald the dawn of exploring the mysteries of life in innovative ways.

关键词： neural bringing innovative

Tetraphenylethene-based hole transporting material for highly efficient and stable perovskite solar cells

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Science China Chemistry 2024年第6期67卷 2009-2015页

作者： Peng Wang pei Yuan Chenghao Ge Rongjun Zhao Lin Xie Yong hua School of Materials and Energy Yunnan UniversityKunming650091China

2,2,7,7-Tetrakis-(N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD)has been identified as the most widely used and effective hole transporting material(HTM)in perovskite solar cells(PSCs).However,the complicated multistep synthesis and low intrinsic hole mobility of Spiro-OMe TAD limit its commercialized application.Therefore,developing highly efficient HTMs with less synthetic steps becomes increasingly important.Moreover,understanding hot carriers transfer dynamics at the interface of perovskite layer and hole transport layer is crucial for further enhancing PSCs performance towards Shockley-Queisser limit,which still lacks full investigation to date.Herein,a new HTM based on tetraphenylethene(WP1)was successfully synthesized by a simple one-step reaction process.It was found that WP1-based HTM exhibits more matched energy level,higher hole mobility and conductivity than those of the control Spiro-OMe TAD.The femtosecond transient absorption results reveal that the transfer rate of hot holes in perovskite/WP1 sample is four times higher than that of perovskite/Spiro-OMeTAD,thereby helping enhance the device performance.Consequently,the efficiency of PSCs is enhanced to 24.04%(WP1)from 22.85%(Spiro-OMeTAD).Moreover,the un-encapsulated device prepared with WP1 exhibits better long-term stability,retaining 87%of its initial PCE value after storing for 72 days under air environment,while the reference device shows76%of its initial value.This work indicates that simple tetraphenylethene-based organic small molecule could be a very promising HTM candidate for highly efficient PSCs,and gives some significant insights for understanding intrinsic hot carriers transfer dynamics in device.

关键词： tetraphenylethene hole transporting material perovskite solar cells mobility hot carrier

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Multi-Objective Equilibrium Optimizer for Feature Selection in High-Dimensional English Speech Emotion Recognition

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Computers, Materials & Continua 2024年第2期78卷 1957-1975页

作者： Liya Yue pei hu Shu-Chuan Chu Jeng-Shyang Pan Fanli Business School Nanyang Institute of TechnologyNanyang473004China School of Computer and Software Nanyang Institute of TechnologyNanyang473004China College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China Department of Information Management Chaoyang University of TechnologyTaichung413310Taiwan

Speech emotion recognition(SER)uses acoustic analysis to find features for emotion recognition and examines variations in voice that are caused by emotions.The number of features acquired with acoustic analysis is extremely high,so we introduce a hybrid filter-wrapper feature selection algorithm based on an improved equilibrium optimizer for constructing an emotion recognition system.The proposed algorithm implements multi-objective emotion recognition with the minimum number of selected features and maximum accuracy.First,we use the information gain and Fisher Score to sort the features extracted from signals.Then,we employ a multi-objective ranking method to evaluate these features and assign different importance to them.Features with high rankings have a large probability of being selected.Finally,we propose a repair strategy to address the problem of duplicate solutions in multi-objective feature selection,which can improve the diversity of solutions and avoid falling into local traps.Using random forest and K-nearest neighbor classifiers,four English speech emotion datasets are employed to test the proposed algorithm(MBEO)as well as other multi-objective emotion identification techniques.The results illustrate that it performs well in inverted generational distance,hypervolume,Pareto solutions,and execution time,and MBEO is appropriate for high-dimensional English SER.

关键词： Speech emotion recognition filter-wrapper high-dimensional feature selection equilibrium optimizer multi-objective

Performance analysis of a photovoltaic/thermal system with lunar regolith-based thermal storage for the lunar base

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Science China(Technological Sciences) 2024年第4期67卷 1113-1123页

作者： SUN WenGan ZHAO Bin pei Yu SHI LingFeng hu MaoBin LI MuJun REN Xiao pei Gang Deep Space Exploration Laboratory Hefei 230026China Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230026China Department of Mechanical and Aerospace Engineering University of California San DiegoLa JollaCA 92093USA Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China College of New Energy China University of Petroleum(East China)Qingdao 266000China

Powering a moon base,especially keeping it warm during the long lunar night,is a big challenge.This paper introduces a photovoltaic/thermal(PV/T)system incorporating regolith thermal storage to solve the challenge of power and heat provision for the lunar base simultaneously.The vacuum of space around the moon helps this system by reducing heat loss.During the moon's daytime,the system not only generates electricity but also captures heat.This stored heat in the regolith is then used at night,reducing the amount of equipment we need to send from Earth.The spectrally selective PV/T panels are designed to absorb a wide range of sunlight(0.3–2.5μm)while minimizing heat loss in the infrared range(3–30μm).Simulation results of the hybrid solar energy system indicate the average value of the overall efficiency is 45.9%,which relatively elevates 56.1%compared to the PV system.The launch mass of the proposed PV/T system is only 8.4%of a traditional photovoltaic-lithium battery system with the same amount of energy storage.And the total specific energy of the proposed system is 7.3 kWh kg^(-1),while that of the photovoltaic-lithium battery system is about 0.3 kWh kg^(-1).In summary,this study proposes an alternative combined heat and electricity supply system for the lunar base,which can greatly reduce the launch mass and free up load for other scientific research equipment.

关键词： in-situ resource utilization(IRSU) regolith thermal storage photovoltaic/thermal(PV/T) spectral selectivity

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