简介:GREENMESSENGER──WOMEN’SMOUNTAINPRODUCTIONBRIGADEINYOUXIVILLAGEByprojectteam“WomenandSocialForestry”Womeninmountainousareaswar...
简介:ThebimodalTaylorexpansionmethodofmoments(B-TEMOM)modelschemewasdevelopedtosimulatetheformationandevolutionofvehicleexhaustparticles.Twoindependenttypesoflog-normalparticlesizedistributionswereselectedintheB-TEMOMmodelscheme,comprisinglargeandsmallparticlestorepresentbackground(i.e.,thesurroundingenvironment)andvehicleexhaustparticles,respectively.Concentrationdistributionsofexhaustandbackgroundparticlesderivedusingthismodelschemewereverifiedagainstresultsfromamovingsectionalmethodandthebimodalquadraturemethodofmoments,showingexcellentagreement.Theeffectsofvehicletailpipeex让cond让ions(e.g.,exhaustparticleconcentrationsandvelocity),sulfurcontent,andrelativehumidityontheevolutionofparticleswereinvestigatednumerically.Bothtwo-dimensionalandthree-dimensionalnumericalsimulationsshowedthattailpipeexitvelocityandrelativehumid让ydidnotgreatlyaffectthesteady-stateconcentrationsorthediametersofparticlesinurbanatmospheres.Althoughanincreaseinsulfurcontenthadlittleeffectontheparticleconcentration,itledtobackgroundparticleswithlargergeometricaveragediameterenteringtheenvironment.ThiscoupledCFD-B-TEMOMnumericalmodelprovidesasimplebutaccurateandefficientmethodforstudyingbimodalaerosoldynamics.
简介:BasedontheTaylorseriesmethodandLi’sspatialdifferentialmethod,ahigh-orderhybridTaylor–Lischemeisproposed.Theresultsofalinearadvectionequationindicatethat,usingtheinitialvaluesofthesquare-wavetype,aresultwiththirdorderaccuracyoccurs.However,usinginitialvaluesassociatedwiththeGaussianfunctiontype,aresultwithveryhighprecisionappears.Thestudydemonstratesthat,whentheorderofthetimeintegralismorethanthree,thecorrespondingoptimalspatialdifferenceordercouldbehigherthansix.Theresultsindicatethatthereasonforwhythereisnoimprovementrelatedtoanorderofspatialdifferenceabovesixistheuseofatimeintegralschemethatisnothighenough.TheauthoralsoproposesarecursivedifferentialmethodtoimprovetheTaylor–Lischeme’scomputationspeed.Amorerapidandhighprecisionprogramthandirectcomputationofthehigh-orderspacedifferentialitemisemployed,andthecomputationspeedisdramaticallyboosted.Basedonamultiple-precisionlibrary,theultrahigh-orderTaylor–LischemecanbeusedtosolvetheadvectionequationandBurgers’equation.
简介:Inthispaper,theflowpatternsobservedinhorizontalCouette-Taylorflow(CTF)werecorrelatedusingdimensionlessnumbers.Theanalysisoftheresultsshowedthatthestructureoftheflowwasanoutcomeofinteractionbetweenfluidinertiarelatedtoaxialandrotationalflowsandgravitation.Therefore,theflowstructureswerecorrelatedusingaxialandangularReynoldsnumbers,andArchimedesnumberforthegivenvalueofgas-to-liquidflowratio.Finally,thecorrelationforthepredictionofthetransitiontotheflowregimeobservedathighrotationalspeedswasproposed.ThecomparisonwithexperimentscarriedoutintheverticalCTFfromtheliteratureshowedthatthiscorrelationcanalsobeusefulinthecaseofverticalflow.
简介:摘要 《folklore》是美国女歌手Taylor Swift于2020年7月24日发行的第8张录音室音乐专辑。同时,Taylor Swift也凭借该专辑获得第63届格莱美奖年度专辑。这张专辑不管是从封面还是到歌曲本身,画面视觉感十足,本文章以《音乐美学》第四章“音乐的表现对象”第三节“音乐与绘画”中的“音乐表现画面和视觉形象的几种手段”为依据,以此来分析专辑《folklore》中的部分歌曲所体现出来的音乐画面视觉。
简介:利用NCEP再分析格点资料、常规观测资料、自动站降水资料、0.1°×0.1°的FY-2E云顶亮温资料,对2013年6月29日至7月1日发生在四川东部的大暴雨过程进行分析,结合涡度收支方程重点分析了引发这次大暴雨的西南涡结构。结果表明:在西南低涡发生发展过程中,对低涡发展起直接作用的是水平辐合辐散项和水平平流项,低涡形成前水平辐合辐散项起主要贡献,低涡形成后水平平流项贡献增大,并在对流层中低层以正贡献为主,扭转项贡献最小,而垂直输送项在低涡形成前期以正贡献为主,低涡减弱阶段以负贡献为主;在西南低涡形成前期,对流层高层有位涡大值区向下传输至中层,中高层正位涡叠加在低层负位涡之上,有利于低层低涡的发展及不稳定能量的存储与释放,是低涡维持发展的重要因素。
简介:这份报告为金nanoparticles的合成描述Fagopyrumesculentum叶子的ethnolic摘录的使用。紫外可见的光谱学分析显示了金nanoparticles的成功的形成。综合nanoparticles被传播电子显微镜学(TEM)描绘,高分辨率TEM(HRTEM)并且被发现在有8.3nm的一种平均尺寸的形状球形、六角形、三角形。金nanoparticles的水晶的性质从X光检查衍射(XRD)和精选区域的电子衍射(SAED)被证实模式。Fourier变换红外线(英尺红外)并且精力散的X光检查分析(EDX)在金nanoparticles的表面上建议了器官的biomolecules的存在。对癌症房间衬里的人的HeLa,MCF-7和IMR-32的Cytotoxicity测试表明金nanoparticles是无毒的并且因此在各种各样的生物医学的应用为使用有潜力。
简介:Energyconsumptionofsensornodesisoneofthecrucialissuesinprolongingthelifetimeofwirelesssensornetworks.Oneofthemethodsthatcanimprovetheutilizationofsensornodesbatteriesistheclusteringmethod.Inthispaper,weproposeagreenclusteringprotocolformobilesensornetworksusingparticleswarmoptimization(PSO)algorithm.Wedefineanewfitnessfunctionthatcanoptimizetheenergyconsumptionofthewholenetworkandminimizetherelativedistancebetweenclusterheadsandtheirrespectivemembernodes.Wealsotakeintoaccountthemobilityfactorwhendefiningtheclustermembership,sothatthesensornodescanjointheclusterthathasthesimilarmobilitypattern.Theperformanceoftheproposedprotocoliscomparedwithwell-knownclusteringprotocolsdevelopedforwirelesssensornetworkssuchasLEACH(low-energyadaptiveclusteringhierarchy)andprotocolsdesignedforsensornetworkswithmobilenodescalledCM-IR(clusteringmobility-invalidround).Inaddition,wealsomodifytheimprovedversionofLEACHcalledMLEACH-C,sothatitisapplicabletothemobilesensornodesenvironment.SimulationresultsdemonstratethattheproposedprotocolusingPSOalgorithmcanimprovetheenergyconsumptionofthenetwork,achievebetternetworklifetime,andincreasethedatadeliveredatthebasestation.
简介:ThederivationofGreenfunctioninatwo-layerfluidmodelhasbeentreatedindifferentways.Inatwo-layerfluidwiththeupperlayerhavingafreesurface,thereexisttwomodesofwavespropagatingduetothefreesurfaceandtheinterface.ThispaperisconcernedwiththederivationofGreenfunctionsinthethreedimensionalcaseofastationarysourceoscillating.Thesourcepointislocatedeitherintheupperorlowerpartofatwo-layerfluidoffinitedepth.Thederivationiscarriedoutbythemethodofsingularities.Thismethodhasanadvantageinthatitinvolvesrepresentingthepotentialasasumofsingularitiesormultipolesplacedwithinanystructuresbeingpresent.Furthermore,experienceshowsthatthesystemsofequationsresultedfromusingasingularitymethodpossessexcellentconvergencecharacteristicsandonlyafewequationsareneededtoobtainaccuratenumericalresults.Validationisdonebyshowingthatthederivedtwo-layerGreenfunctioncanbereducedtothatofasinglelayeroffinitedepthorthattheupperGreenfunctioncoincideswiththatofthelower,foreachcase.Theeffectofthedensityontheinternalwavesisdemonstrated.Also,itisshownhowthesurfaceandinternalwaveamplitudesarecomparedforboththewavemodes.Thefluidinthiscaseisconsideredtobeinviscidandincompressibleandtheflowisirrotational.