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World Journal of Gastroenterology 2021年第7期27卷 561-575页

作者： Gao-Feng Zhan Yue Wang Ning Yang ai-lin luo Shi-Yong Li Department of Anesthesiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Department of Anesthesiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

Although coronavirus(CoV)infection is often characterized by respiratory symptoms,the virus can also result in extrapulmonary symptoms,especially the symptoms related to the digestive *** outbreak of coronavirus disease 2019(COVID-19)is currently the world’s most pressing public health threat and has a significant impact on civil societies and the global *** occurrence of digestive symptoms in patients with COVID-19 is closely related to the development and prognosis of the ***,thus far,there are no specific antiviral drug or vaccine approved for the treatment or prevention of ***,we elaborate on the effects of CoVs on the digestive system and the potential underlying mechanisms.

关键词： SARS-CoV-2 Gastrointestinal diseases Liver dysfunction COVID-19 Coronavirus Mechanisms

A Self-Attention Based Dynamic Resource Management for Satellite-Terrestrial Networks

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China Communications 2024年第4期21卷 136-150页

作者： lin Tianhao luo Zhiyong School of Electronics and Communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Peng Cheng Laboratory Shenzhen 518107China

The satellite-terrestrial networks possess the ability to transcend geographical constraints inherent in traditional communication networks,enabling global coverage and offering users ubiquitous computing power support,which is an important development direction of future *** this paper,we take into account a multi-scenario network model under the coverage of low earth orbit(LEO)satellite,which can provide computing resources to users in faraway areas to improve task processing ***,LEO satellites experience limitations in computing and communication resources and the channels are time-varying and complex,which makes the extraction of state information a daunting ***,we explore the dynamic resource management issue pertaining to joint computing,communication resource allocation and power control for multi-access edge computing(MEC).In order to tackle this formidable issue,we undertake the task of transforming the issue into a Markov decision process(MDP)problem and propose the self-attention based dynamic resource management(SABDRM)algorithm,which effectively extracts state information features to enhance the training *** results show that the proposed algorithm is capable of effectively reducing the long-term average delay and energy consumption of the tasks.

关键词： mobile edge computing resource management satellite-terrestrial networks self-attention

Numerical analysis of wind effects on aerodynamic characteristics of a ducted fan

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Chinese Journal of Aeronautics 2024年第5期37卷 263-280页

作者： Yiwei luo Tianfu ai Yuhang HE Bin XU Yuping QIAN Yangjun ZHANG State Key Laboratory of Intelligent Green Vehicle and Mobility School of Vehicle and MobilityTsinghua UniversityBeijing 100084China Key Laboratory of Conveyance and Equipment Ministry of Education East China Jiaotong UniversityNanchang 330013China Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Ducted fans have been extensively used in Unmanned Aerial Vehicles(UAVs)for a variety of missions because of high efficiency,high safety and low ***,as a kind of typical meteorological condition,brings significant aerodynamic interference to the ducted fan,which seriously threatens flight stability and *** this work,the numerical simulation with the Unsteady Reynolds Averaged Navier-Stokes(URANS)method and the sliding mesh technique is performed to evaluate the steady wind *** results show that the wind will lead to serious unsteady effects in the flow field,and the thrust fluctuates at the blade passing frequency of 200 *** the wind speed increases,the rotor thrust increases,the duct thrust decreases,and the total thrust changes *** instability may occur when the wind speed exceeds 8 m/*** the angle of low-speed wind increases,the rotor thrust changes little,the duct thrust increases,and the total thrust *** addition,we figure out that cases with the same crosswind ratio are similar in results,and increasing the rotating speed or fan radius is beneficial to performance improvement in *** findings are essential to the ducted fan design and UAV flight control design for stable and safe operations in wind conditions.

关键词： Unmanned Aerial Vehicle(UAV) Ducted fan Wind effect Thrust fluctuations Computational Fluid Dynamics(CFD)

A Server Placement Algorithm for Reducing Risk and Improving Power Utilization in Data Centers

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Tsinghua Science and Technology 2024年第1期29卷 158-173页

作者： Rui Chen Huikang Huang Xiaoxuan luo Weiwei lin School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Peng Cheng Laboratory Shenzhen 518066China

As the power demand in data centers is increasing,the power capacity of the power supply system has become an essential resource to be *** many data centers use power oversubscription to make full use of the power capacity,there are unavoidable power supply risks associated with ***,how to improve the data center power capacity utilization while ensuring power supply security has become an important *** solve this problem,we first define it and propose a risk evaluation metric called Weighted Power Supply Risk(WPSRisk).Then,a method,named Hybrid Genetic Algorithm with Ant Colony System(HGAACS),is proposed to improve power capacity utilization and reduce power supply risks by optimizing the server placement in the power supply *** uses historical power data of each server to find a better placement solution by population *** possesses not only the remarkable local search ability of Ant Colony System(ACS),but also enhances the global search capability by incorporating genetic operators from Genetic Algorithm(GA).To verify the performance of HGAACS,we experimentally compare it with five other placement *** experimental results show that HGAACS can perform better than other algorithms in both improving power utilization and reducing the riskof powersupply system.

关键词： server placement power utilization power supply risk swarm intelligence algorithm

Self-actuating protection mechanisms for safer lithium-ion batteries

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Journal of Energy Chemistry 2024年第7期94卷 181-198页

作者： Yang luo Chunchun Sang Kehan Le Hao Chen Hui Li Xinping ai Hubei Key Lab of Electrochemical Power Sources College of Chemistry&Molecular ScienceWuhan UniversityWuhan 430072HubeiChina state Key Laboratory of New Textile Materials&Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200HubeiChina

Safety issue is still a problem nowadays for the large-scale application of lithium-ion batteries(LIBs)in electric vehicles and energy storage *** unsafe behaviors of LIBs arise from the thermal run-away,which is intrinsically triggered by the overcharging and *** improve the safety of LIBs,various protection strategies based on self-actuating reaction control mechanisms(SRCMs)have been proposed,including redox shuttle,polymerizable monomer additive,potential-sensitive separator,thermal shutdown separator,positive-temperature-coefficient electrode,thermally polymerizable addi-tive,and reversible thermal phase transition *** build-in protection mechanisms,these meth-ods can sensitively detect either the temperature change inside battery or the potential change of the electrode,and spontaneously shut down the electrode reaction at risky conditions,thus preventing the battery from going into thermal *** their advantages in enhancing the intrinsic safety of LIBs,this paper overviews the research progresses of SRCMs after a brief introduction of thermal runaway mechanism and limitations of conventional thermal runaway mitigating *** importantly,the current states and issues,key challenges,and future developing trends of SRCTs are also discussed and outlined from the viewpoint of practical application,aiming at providing insights and guidance for developing more effective SRCMs for LIBs.

关键词： Li-ion battery Safety Thermal runaway Thermal protection Overcharge protection

Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

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Research in Astronomy and Astrophysics 2024年第3期24卷 194-204页

作者： Pei-Xin luo Bao-lin Tan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific ***,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly *** on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred *** on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction *** for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle *** peak year will occur approximately in 2024,and the period will be about 11±1 *** for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr.

关键词： Sun activity-Sun evolution-(Sun) sunspots-methods data analysis

Multicomponent remote C(sp^(2))–H bond addition by Ru catalysis:An efficient access to the alkylarylation of 2H-imidazoles

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Chinese Chemical Letters 2024年第10期35卷 257-261页

作者： Yi luo lin Dong Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Sequential C–H bond addition with two different coupling partners is a powerful method for the rapid and modular construction of complex molecules based on simple starting ***,an efficient ruthenium-catalysed multicomponent long-range C–H functionalization of 2H-imidazoles was *** protocol showed good substrate suitability and yielded alkyl arylation products with potential biological activity.

关键词： Remote C-H functionalization Multi-component reaction Ruthenium catalysis 2H-Imidazoles

Discrete Boltzmann model with split collision for nonequilibrium reactive flows

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Communications in Theoretical Physics 2024年第8期76卷 164-186页

作者： Chuandong lin Kai H luo Huilin Lai Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical Engineering National University of Singapore10 Kent Ridge Crescent119260Singapore Department of Mechanical Engineering University College LondonTorrington PlaceLondon WC1E 7JEUnited Kingdom School of Mathematics and Statistics Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Key Laboratory of Analytical Mathematics and Applications(FJKLAMA)Center for Applied Mathematics of Fujian Province(FJNU)Fujian Normal University350117 FuzhouChina

A multi-relaxation-time discrete Boltzmann model(DBM) with split collision is proposed for both subsonic and supersonic compressible reacting flows, where chemical reactions take place among various components. The physical model is based on a unified set of discrete Boltzmann equations that describes the evolution of each chemical species with adjustable acceleration, specific heat ratio, and Prandtl number. On the right-hand side of discrete Boltzmann equations, the collision,force, and reaction terms denote the change rates of distribution functions due to self-and crosscollisions, external forces, and chemical reactions, respectively. The source terms can be calculated in three ways, among which the matrix inversion method possesses the highest physical accuracy and computational efficiency. Through Chapman-Enskog analysis, it is proved that the DBM is consistent with the reactive Navier-Stokes equations, Fick's law and the Stefan-Maxwell diffusion equation in the hydrodynamic limit. Compared with the one-step-relaxation model, the split collision model offers a detailed and precise description of hydrodynamic, thermodynamic, and chemical nonequilibrium effects. Finally, the model is validated by six benchmarks, including multicomponent diffusion, mixture in the force field, Kelvin-Helmholtz instability, flame at constant pressure, opposing chemical reaction, and steady detonation.

关键词： discrete Boltzmann method reactive flow detonation nonequilibrium effect

An mmWave Dual-Band Integrated Substrate Gap Waveguide Single Cavity Filter with Frequency Selectivity

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China Communications 2024年第1期21卷 188-199页

作者： Qiuhua lin Dongya Shen Lihui Wang Zhiyong luo School of Electronics and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China School of Information Science and Engineering Yunnan UniversityKunming 650091China Pengcheng Laboratory Shenzhen 518107China Shenzhen Key Laboratory of Navigation and Communication Integration Shenzhen 518107China

A novel dual-band ISGW cavity filter with enhanced frequency selectivity is proposed in this paper by utilizing a multi-mode coupling *** cavity is designed to control the number of modes,and then the ports are determined by analyzing the coupling relationship between these selected *** synthesizing the coupling matrix of the filter,a nonresonating node(NRN)structure is introduced to flexibly tune the frequency of modes,which gets a dualband and quad-band filtering response from a tri-band filter no the ***,a frequency selective surface(FSS)has been newly designed as the upper surface of the cavity,which significantly improves the bad out-of-band suppression and frequency selectivity that often exists in most traditional cavity filter designs and *** results show that its two center frequencies are f01=27.50 GHz and f02=32.92GHz,*** with the dual-band filter that there is no the FSS metasurface,the out-of-band suppression level is improved from measured 5 dB to18 dB,and its finite transmission zero(FTZ)numbers is increased from measured 1 to 4 between the two designed *** with the tri-band and quadband filter,its passband bandwidth is expanded from measured 1.17%,1.14%,and 1.13% or 1.31%,1.50%,0.56%,and 0.57% to 1.71% and 1.87%.In addition,the filter has compact,small,and lightweight characteristics.

关键词： coupling topology frequency selectivity non-resonating node(NRN) out-of-band suppression single ISGW cavity filter

Structural engineering of hard carbon through spark plasma sintering for enhanced sodium-ion storage

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Rare Metals 2024年第9期43卷 4274-4285页

作者： Hao-Ming Xiao Heng Zheng Ping Yuan Jun-Hui luo lin-lin Shen Jie-Feng Tan Xian-You luo De Li Yong Chen Guangdong Key Laboratory for Hydrogen Energy Technologies School of Materials Science and Hydrogen EnergyFoshan UniversityFoshan 528000China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesHainan UniversityHaikou 570228China

Hard carbon(HC)has emerged as one of the superior anode materials for sodium-ion batteries(SIBs),with its electrochemical performance significantly influenced by the presence of oxygen functional groups and its closed pore ***,current research on the structural adjustment of these oxygen functional groups and the closed pore architecture within HC remains ***,energy-efficient and contamination-free spark plasma sintering technology was employed to tune the structure of coconut-shell HC,resulting in significant adjustments to the content of carboxyl(decreasing from 5.71 at%to 2.12 at%)and hydroxyl groups(decreasing from 7.73 at%to 6.26 at%).Crucially,these modifications reduced the irreversible reaction of oxygen functional groups with Na^(+).Simultaneously,a substantial number of closed pores with an average diameter of 1.22 nm were generated within the HC,offering an ideal environment for efficient Na^(+)*** structural changes resulted in a remarkable improvement in the electrochemical performance of the modified *** reversible specific capacity of the modified HC surged from 73.89 mAh·g^(-1)to an impressive 251.97 m Ah·g^(-1)at a current density of 50 mA·g^(-1).Even at 400 mA·g^(-1),the reversible specific capacity increased significantly from 14.55 to 85.44 mAh·g^(-1).Hence,this study provides a novel perspective for designing tailored HC materials with the potential to develop high-performance SIBs.

关键词： Hard carbon Spark plasma sintering Sodiumion batteries Closed pores Oxygen functional groups