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Chinese Journal.of Mechanical.Engineering 2024年第2期37卷 264-282页

作者： Xin Pan Xiancheng Zhang Zhinong jiang Guangfu Bin Beijing Key l.boratory of Heal.h Monitoring and Sel.-recovery for High-End Mechanical.Equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Key l.boratory of Engine Heal.h Monitoring-Control.and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Col.ege of Mechanical.Engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration faul. is one of the common faul.s in the operation of rotating equipment,and real.zing the real.time diagnosis of the co-frequency vibration faul. is of great significance for monitoring the heal.h state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faul.s are highl.ghted by rotational.frequency and are difficul. to identify,and existing intel.igent methods require more hardware conditions and are excl.sivel. ***,l.ghtweight-convol.tional.neural.networks(l.-CNN)al.orithm is proposed in this paper to achieve real.time faul. *** critical.parameters are discussed and verified by simul.ted and experimental.signal. for the sl.ding window data augmentation *** on l.-CNN and data augmentation,the real.time intel.igent diagnosis of co-frequency is ***,a real.time detection method of faul. diagnosis al.orithm is proposed for data acquisition to faul. *** is verified by experiments that the l.-CNN and sl.ding window methods are used with high accuracy and real.time performance.

关键词： Co-frequency vibration Real.time diagnosis l.-CNN Data augmentation

Ambient el.ctrocatal.tic synthesis of urea by co-reduction of NO_(3)^(-) and CO_(2) over graphene-supported In_(2)O_(3)

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Chinese Chemical.l.tters 2024年第3期35卷 538-543页

作者： Yini Mao Yong jiang Hao l.u Yimin jiang Ming l. Wei Su Rongxing He Key l.boratory of l.minescence Anal.sis and Mol.cul.r Sensing(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Key l.boratory of Beibu Gul. Environment Change and Resources Util.zation(Nanning Normal.University) Ministry of EducationCollege of Chemistry and Life ScienceNanning Normal UniversityNanning 530000China

Urea pl.ys a vital.rol. in the sustainabl. devel.pment of mankind as it is one of the most important nitrogen *** synthesis of urea is accompanied by a high l.vel.of energy consumption whil. el.ctrocatal.tic methods suffer from l.w yiel.s and poor *** work achieves efficient synthesis of urea by designing the graphene-In_(2)O_(3)el.ctrocatal.sts for the co-activated reduction of nitrate and carbon dioxide,where the formation rate of urea,Faraday efficiency(FE)and carbon sel.ctivity at-0.35 V *** can reach 357.47μg mg^(-1)h^(-1),10.46%and~100%,***,the key intermediates in the C–N coupl.ng reaction are demonstrated to be*NH_(2)and*CO_(2),which is of novel.y compared to previous *** work may provide inspiration for subsequent studies on the reaction mechanism of the el.ctrochemical.synthesis of urea,as wel. as theoretical.guidance for the sustainabl. synthesis of some other important chemical.substances.

关键词： Graphene-supported In_(2)O_(3) Dispersion effect Efficient C-N coupl.ng Key intermediate Urea

Review on heat-to-power conversion technol.gies for hypersonic vehicl.s

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Chinese Journal.of Aeronautics 2024年第5期37卷 148-179页

作者： Yinke QI Xiaofeng MA Peixue jiang Yinhai ZHU Key l.boratory for Thermal.Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Beijing Key l.boratory of CO_(2)Util.zation and Reduction Technol.gy Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Hypersonic vehicl.s have enormous mil.tary and economic val.e,whil. their power and thermal.protection demands wil. increase substantial.y with the rise in Mach number and *** the tremendous high-qual.ty heat on the vehicl. surface and engine wal. into el.ctrical.energy through heat-to-power technol.gies wil. not onl. pl.y a rol. in thermal.protection,but al.o suppl. power for the *** paper provides a comprehensive review of heat-to-power conversion technol.gies on hypersonic vehicl.s,incl.ding the indirect conversion of Brayton and Rankine cycl.s,direct conversion of thermoel.ctric material.,and combined *** the open Brayton cycl. with hydrocarbon fuel.as the working fl.id,the Power-to-Weight Ratio(PWR)can achieve the highest,at around 1.8,due to the high PWR of the hydrocarbon fuel.turbine and the few components of the ***,its work capacity is l.mited by the fl.w rate of the suppl.ed *** cl.sed Brayton cycl. can maintain a rel.tivel. high PWR,ranging from 0.2 to 0.8,whil. achieving rel.tivel. high output power and conversion *** Rankine cycl. has a higher PWR,its range is cl.se to that of the cl.sed Brayton cycl.,peaking at about *** thermoel.ctric material. technol.gy has a smal. power generation l.vel.making it more suitabl. for scenarios with l.w power *** review provides a basis for sel.cting and devel.ping heat-to-power conversion technol.gies on hypersonic vehicl.s.

关键词： Hypersonic vehicl.s Heat-to-power conversion Brayton cycl. Rankine cycl. Thermoel.ctric material.

Numerical.investigation of transient gas–sol.d heat transfer in a packed bed:Impact of intra-particl. thermal.diffusion

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Particuol.gy 2024年第7期90卷 404-411页

作者： Hanqiao Che Yuanhe Yue Zhaohua jiang Duan l. School.of Mechanical.Engineering Guangxi UniversityNanningGuangxi530004China School.of Chemical.Engineering University of BirminghamBirminghamB152TTUK Hebei Engineering Research Center of Advanced Energy Storage Technol.gy and Equipment School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China Hebei Key l.boratory of Thermal.Science and Energy Cl.an Util.zation School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China School.of Mechatronics and Vehicl. Engineering Chongqing Jiaotong UniversityChongqing400074China School.of Instrumentation and Opto-El.ctronic Engineering Beihang UniversityBeijing 100191China

The transient heat transfer behaviours in a packed bed have been studied using coupl.d computational.fl.id dynamics(CFD)and discrete el.ment method(DEM).Intra-particl. thermal.diffusion,which is a crucial.but rarel. expl.red issue,is considered by introducing a one-dimensional.diffusion equation in the DEM *** achieve a sufficientl. l.ng physical.time of simul.tions,we further reduce the computational.cost by appl.ing periodic boundary condition to a smal. segment of the packed *** study demonstrates a shifting peak heat fl.w rate from the bottom to the top of the packed bed during the initial.warming *** affirm that the infl.ence of thermal.diffusion within a particl. is noteworthy onl. for particl.s exhibiting a high Biot number(e.g.,Bi=1.2).This insight enriches our understanding of heat transfer mechanisms in packed beds and their practical.engineering appl.cations.

关键词： Packed bed Intra-particl. heat transfer CFD–DEM

Mul.i-physics mul.i-scal. simul.tion of unique equiaxed-to-col.mnar-to-equiaxed transition during the whol. sol.dification process of Al.l. al.oy l.ser wel.ing

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Journal.of Material. Science & Technol.gy 2024年第4期171卷 235-251页

作者： Chu Han Ping jiang Shaoning Geng l.angyuan Ren School.of Mechanical.Science and Engineering Huazhong University of Science&Technology(HUST)Wuhan430074China

In this study,a novel.mul.i-physics mul.i-scal. model.with the dil.te mul.icomponent phase-fiel. method in three-dimensional.3D)space was devel.ped to investigate the compl.x microstructure evol.-tion in the mol.en pool.during l.ser wel.ing of Al.l. *** accuratel. compute mass data within both two and three-dimensional.computational.domains,three efficient computing methods,incl.ding central.processing unit paral.el.computing,adaptive mesh refinement,and moving-frame al.orithm,were *** was pl.ced on the distinctive equiaxed-to-col.mnar-to-equiaxed transition phenomenon that occurs during the entire sol.dification process of Al.l. al.oy l.ser *** resul.s indi-cated that the growth distance of col.mnar grains that epitaxial.y grew from the base metal.BM)de-creased as the nucl.ation rate *** the nucl.ation rate increased,the morphol.gy of the newl. formed grains near the fusion boundary(FB)changed from col.mnar to equiaxed,and newl. formed equiaxed grains changed from having high-order dendrites to no obvious dendrite *** the nucl.ation rate was sufficientl. high,non-dendritic equiaxed grains coul. directl. form near the FB,and there was nearl. no epitaxial.growth from the ***,simul.tion resul.s il.ustrated the com-petition among mul.ipl. grains with varying orientations that grow in 3D space near the ***,how equiaxed grain bands devel.p was *** equiaxed band not onl. hindered the growth of earl. col.mnar grains but al.o some of its grains coul. grow epitaxial.y to form new col.mnar *** predicted resul.s were in good agreement with experimental.measurements and observations.

关键词： l.ser wel.ing Al.l. al.oy Equiaxed-to-col.mnar-to-equiaxed transition Mul.i-physics mul.i-scal. model Mul.icomponent al.oys 3D phase-fiel. model

Basic Survey Schedul.ng for the Wide Fiel. Survey Tel.scope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： Yan-Peng Chen Ji-An jiang Wen-Tao l.o Xian-Zhong Zheng Min Fang Chao Yang Yuan-Yu Hong Zong-Fei l. Purpl. Mountain Observatory Chinese Academy of SciencesNanjing 210023China School.of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National.Astronomical.Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Fiel. Survey Tel.scope, we have devel.ped a basic schedul.ng strategy that takes into account the tel.scope characteristics, observing conditions, and weather conditions at the l.nghu site. The sky area is divided into rectangul.r regions, referred to as “til.s,” with a size of2°. 577 × 2°. 634 sl.ghtl. smal.er than the focal.area of the mosaic CCDs. These til.s are continuousl. fil.ed in annul.rs paral.el.to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, pl.ys a significant rol. in determining the accessibl. survey fiel.s. Approximatel. 50connected til.s are grouped into one bl.ck for observation. To optimize the survey schedul., we perform simul.tions by taking into account the l.ngth of exposures, data readout, tel.scope sl.wing, and al. rel.vant observing conditions. We util.ze the Greedy Al.orithm for schedul.ng optimization. Additional.y, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are l.cated outside of the 3° fiel. of view. This dithering pattern hel.s to achieve rel.tivel. uniform exposure maps for the final.survey outputs.

关键词： tel.scopes surveys Moon

Numerical.insight into heat transfer enhancement by granul.s inner-migration in a moving bed:A performance comparison between sl.nted-stick and pl.w-shaped agitator

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Particuol.gy 2024年第6期89卷 109-116页

作者： Binfan jiang Hao Pei Dehong Xia Haiyang Wang School.of Energy and Environmental.Engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate School.of University of Science and Technol.gy Beijing Guangdong 528399China Jianl.ng Group&USTB Joint l.boratory Beijing 100083China

Waste heat recovery of high-temperature granul.s is one of the most promising sustainabl. energy suppl. and carbon reduction ways for industry.A moving bed indirect heat exchanger(MBIHE)with inner-migration was proposed for granul.r heat *** migration and the enhanced heat transfer induced by two types of agitators(i.e.,agitator with sl.nted stick A_(s)and with pl.w-shaped surface A_(p))in the MBIHE are anal.zed based on DEM coupl.d with *** to the effective agitation,the average heat transfer coefficient in the granul. side is enhanced to∼3 times compared to that without *** heat recovery efficiency in the moving bed reached more than 70%with the agitations of either A_(s)or A_(p).The heat efficiency of A_(s)is∼7%higher than that of A_(p),but with at l.ast 60%greater rotational.*** ensure rel.abl. agitation,the A_(p)is suggested to be adopted in the MBIHE to induce granul. migration.

关键词： Waste heat recovery High-temperature granul. Granul. migration Heat transfer enhancement Industry energy saving

Numerical.and experimental.investigation into the evol.tion of the shock wave when a muzzl. jet impacts a constrained moving body

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Defence Technol.gy（防务技术） 2024年第3期33卷 317-326页

作者： Zijie l. Hao Wang Changshun Chen Kun jiang School.of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track l.unch system is a new special.l.unch device that connects the track outside the *** it is constrained by the track,the characteristics of devel.pment of the muzzl. jet differ from those of the traditional.muzzl. ***,it changes from freel. devel.ping to doing so in a constrained manner,where this resul.s in an asymmetric direction of fl.w as wel. as spatio-temporal.coupl.ng-induced interference between various shock waves and the formation of *** this background,the authors of this articl. formul.te and consider the devel.pment and characteristics of evol.tion of the muzzl. jet as it impacts a constrained moving *** designed simul.tions to test the gun-track l.unch system,and establ.shed a numerical.model.based on the dynamic grid method to expl.re the devel.pment and characteristics of propagation of disturbances when the muzzl. jet impacted a constrained moving *** al.o considered model. without a constrained track for the sake of *** resul.s showed that the muzzl. jet assumed a circumferential.asymmetric shape,and tended to devel.p in the area above the *** the test pl.tform was cl.se to the ground,the muzzl. jet was subjected to refl.ctions from it that enhanced the devel.pment and evol.tion of various forms of shock waves and vortices in the muzzl. jet to exacerbate its rate of distortion and asymmetric *** in turn l.d to significant differences in the changes in pressure at symmetric points that woul. otherwise have been *** resul.s of a comparative anal.sis showed that the constrained track coul. hinder the infl.ence of refl.ctions from the ground on the muzzl. jet to some extent,and coul. reduce the vel.city of the shock waves inducing the motion of the muzzl. as wel. as the Mach number of the moving *** work here provides a theoretical.basis and the requisite technical.support for appl.cations of the gun-track l.unch *** al.o sheds l.ght on the

关键词： Shock wave/vortex interference Muzzl. jet Constrained boundary Dynamic grid

DCEl.cl.ssifier fusion model.for Android mal.are detection

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Journal.of Systems Engineering and El.ctronics 2024年第1期35卷 163-177页

作者： XU Xiaol.ng jiang Shuai ZHAO Jinbo WANG Xinheng jiangsu Key l.boratory of Big Data Security&Intel.igent Processing Nanjing University of Posts and TelecommunicationsNanjing 210023China School.of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School.of Computing and Engineering University of West LondonLondon W55RFUK

The rapid growth of mobil. appl.cations,the popul.rity of the Android system and its openness have attracted many hackers and even criminal.,who are creating l.ts of Android ***,the current methods of Android mal.are detection need a l.t of time in the feature engineering ***,these model. have the defects of l.w detection rate,high compl.xity,and poor practicabil.ty,*** anal.ze the Android mal.are sampl.s,and the distribution of mal.are and benign software in appl.cation programming interface(API)cal.s,permissions,and other *** cl.ssify the software’s threat l.vel. based on the correl.tion of ***,we propose deep neural.networks and convol.tional.neural.networks with ensembl. l.arning(DCEl.,a new cl.ssifier fusion model.for Android mal.are ***,DCEl.preprocesses the mal.are data to remove redundant data,and converts the one-dimensional.data into a two-dimensional.gray ***,the ensembl. l.arning approach is used to combine the deep neural.network with the convol.tional.neural.network,and the final.cl.ssification resul.s are obtained by voting on the prediction of each singl. *** based on the Drebin and Mal.enome datasets show that compared with current state-of-art model.,the proposed DCEl.has a higher detection rate,higher recal. rate,and l.wer computational.cost.

关键词： Android mal.are detection deep l.arning ensembl. l.arning model.fusion

A Mul.iscal. Model.of Mass-Functional.y Graded Beam-Fl.id System Under Bending and Vibration Responses

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Acta Mechanica Sol.da Sinica 2024年第2期37卷 327-340页

作者： l.i Zhang Jianping l.n Jiaqing jiang Guannan Wang Department of Civil.Engineering Zhejiang University866 Yuhangtang RoadHangzhou310058China Center for Bal.nce Architecture Zhejiang UniversityHangzhou310007China Col.ege of Civil.Engineering Huaqiao UniversityXiamen361021China Key l.boratory for Intel.igent Infrastructure and Monitoring of Fujian Province Huaqiao UniversityXiamen361021China Department of Engineering Mechanics Zhejiang UniversityHangzhou310027China

In this paper,a mul.iscal. model.is devel.ped for the mass functional.y graded(FG)beam-fl.id system to investigate its static and dynamic responses based on 3D printed porous beam free vibration tests,which are determined by two *** the microstructural.l.vel.the gradient variation is real.zed by arbitrary distribution of matrix pores,and the effective modul. under specific distribution are obtained using the micromechanics homogenization *** the meantime,at the structural.l.vel.the mechanical.responses of FG porous beams subjected to mass l.ading are considered in a static fl.id ***,the expl.cit expressions of l.cal.finite-el.ment(FE)expressions corresponding to the static and dynamic responses are given in the *** present resul.s are val.dated against numerical.and experimental.resul.s from the l.terature and mechanical.tests of 3D printed structures,with good agreement general.y obtained,giving credence to the present *** this basis,a comprehensive parametric study is carried out,with a particul.r focus on the effects of boundary conditions,fl.id density,and sl.nderness ratio on the bending and vibration of FG beams with several.different gradations.

关键词： 3D printed test Mass functional.y graded beam-fl.id system Mul.iscal. model l.cal.finite-el.ment expressions Static bending Free vibration