简介：在这份报纸，一个理想化的不安追随者“巨浪流动概念的模型”为典型Meiyu，正面的结构被设计包括多相的microphysicalparameterization用一个非静水力学的、完整可压缩的暴风雨规模模型在Meiyu前面向中央规模结构解释ofrainbands。另外，敏感周围的南方的风的垂直分发的数字实验被进行调查中央规模的产生机制两倍雨线。数字实验的结果证明入侵的凉爽、干燥的downdraft由环境向上在北方的风戏加强了一个很重要的角色到中央规模的产生和维护两倍rainbands.Moreover，入侵的干燥、凉爽的downdraft的紧张和规模与当西的喷气的加速向上发生时，集体调整导致的第二环流的紧张有关。

简介：Meso-scalestructuresexistingintheformofparticle-richclusters,streamersorstrandsincirculatingfluidizedbeds,andofascendingbubbleplumesanddescendingliquid-richvorticesinbubblecolumnsandslurry-bedreactors,ascommonlyobserved,haveplayedanimportantroleinthemacro-scalebehaviorofparticle-fluidsystems.Thesemeso-scalestructuresspanawiderangeoflengthandtimescales,andtheirorigin,evolutionandinfluencearestillfarfrombeingwellunderstood.Recentdecadeshavewitnessedtheemergenceofcomputersimulationofparticle-fluidsystemsbasedoncomputa-ionalfluiddynamic(CFD)models.However,strictlyspeakingthesemodelsarefarfrommatureandthecomplexnatureofparticle-fluidsystemsarisingfromthemeso-scalestructureshasbeenposinggreatchallengestoinvestigators.Thereasonmaybethatthecurrenttwo-fluidmodels(TFM)arederivedeitherfromcontinuummechanicsbyusingdifferentkindsofaveragingtechniquesfortheconservationequationsofsingle-phaseflow,orfromthekinetictheoryofgasesinwhichtheassumptionofmolecularchaosisemployed,therebylosingsightofthemeso-scaleheterogeneityatthescaleofcomputationalcellsandleadingtoinaccuratecalculationoftheinteractionforcebetweenparticlesandfluids.Forexample,theoveralldragforceforparticlesinacellisusuallycalculatedfromtheempiricalWen&Yu/Erguncorrelations,whichshouldbesuspectedsincethesecorrelationswereoriginallyderivedfromhomogeneoussystems.Schemestosolvethisproblemforgas-particlessystemsmaybeclassifiedintofourcategories.First,onecouldcapturethedetailedmeso-scalestructureinformationatthecellscalebyemployingtheso-calleddirectnumericalsimulation(DNS)(Hu,1996),thepseudo-particlemodeling(PPM)(Ge&Li,2003),ortheLattice-Boltzmannmethod(LBM)totracktheinterfacebetweengasandparticles.Second,refinementofthecomputationalmeshesmayreducetheheterogeneitytosomeextentandmaybe

简介：Thecatalystlayer(CL)ofprotonexchangemem-branefuelcell(PEMFC)involvesvariousparticlesandporesinmeso-scale,whichhasanimportanteffectonthemass,charge(protonandelectron)andheattransportcoupledwiththeelectrochemicalreactions.Thecoarse-grainedmoleculardynamics(CG-MD)methodisemployedasameso-scalestructurereconstructiontechniquetomimictheself-organizationphenomenainthefabricationstepsofaCL.Themeso-scalestructureobtainedattheequilibriumstateisfurtheranalyzedbymoleculardynamic(MD)softwaretoprovidethenecessarymicroscopicparametersforunderstandingofmulti-scaleand-physicsprocessesinCLs.Theprimaryporesizedistribution(PSD)andactiveplatinum(Pt)surfaceareasarealsocalculatedandthencomparedwiththeexperiments.Inaddition,wealsohighlighttheimplementationmethodtocombinemicroscopicelementarykineticreactionschemeswiththeCG-MDapproachestoprovideinsightintothereactionsinCLs.TheconceptsfromCGmodelingwithparticlehydrodynamics(SPH)andtheproblemsoncouplingofSPHwithfiniteelementmodeling(FEM)methodsarefurtheroutlinedanddiscussedtounderstandtheeffectsofthemeso-scaletransportphenomenainfuelcells.

简介：mesoscale的进化在21222008年6月期间在Dabie山的北区域引起了强壮的降水的对流系统(MCS)被分析，与联系中央的进化一起--放大对流旋涡(MCV)。本地分析和预言系统(臀部)在水平分辨率和1-h时间分辨率在华南重降雨期间试验的3-km(SCHeREX)产生的mesoscale分析数据被利用。结果证明二个过程在对流不稳定性的改进起了关键作用。首先，低级喷气加强了并且变的mesoscale东方，导致温暖湿的气流的集中并且在中间和底层增加对流不稳定性。第二，温暖湿的气流从北方与冷气流交往了，引起在陡峭地泼出潮湿的isentropic表面的附近的增加的垂直涡度。这二个过程的联合行动引起了MCS变日益增多地东方。与MCS联系的冷凝作用释放了潜伏的热并且形成了在中间的对流层加热的大diabatic的层，增加在这层下面的潜在的涡度。潜在的涡度的这增加为低级旋涡发行量的发展创造了有利条件。进一步与这个低级旋涡联系的垂直运动支持了传送对流的发展，创造在深传送对流和低级旋涡发行量之间的积极反馈。这反馈机制不仅支持了MCS的成熟，而且在MCV的进化起了主要作用。由于伴随了旋涡的中心和传送对流的中心一起来的积极反馈的改进形成并且发展的MCV。积极反馈达到顶点，当这二个中心收敛了时，MCV成熟。积极反馈变弱，MCV开始了到二个中心分开了并且分叉的腐烂。

简介：Theeffectsofdifferentconvectiveparameterization,explicitmoistureschemesandsurfaceheat-ingonthemeso-βscalestructureofasqualllinesystemareinvestigated,byusinganimprovedmesoscalemodel.Itisfoundthatthesuccessfulpredictionofmesoscaleconvectivesystemshingesup-onnotonlythesub-gridscaleconvection,butalsotheresolvablescalephasechangeprocessesandthediurnalvariationintheboundarylayer.ThesimultaneousoperationoftheFritsch-Chappellconvectiveschemewithparameterizedmoistdowndraftsandtheprognosticequationsforcloudwater(ice)andrainwater(snow)seemstobeessentialinsimulatingrealisticallyMCSsandreducingoreliminatingtheunrealisticdevelopmentoftheCISK-likeinstabilityassociatedwiththesqualllinesystem.

简介：Inthispaper,timeandspacedistributionregularityofmeso-scaleheavyrainsinfiveselectedtyphoonswhichlandedatFujianfrom1996to1998hasbeenanalyzed.Besides,withhourlydigitizedsatelliteinfraredimagery,thefeaturesofthemesoscalearerevealedforthegenesisandevolutionofmesoscaleconvectivesystemsintyphoons.Itindicatesthattheintensityofmesoscalestormsiscloselyconnectedwiththetemperatureandtheareaofthecoldestcloudcluster.Theheavyrainfallusuallyemergesontheeasternsideofthemesoscaleconvectivecloudclusters,wherethecloudmassisdevelopingandwithadensegradientandbigcurvatureofisolineofthecloudtoptemperature.

简介：Overthelastdecade,computationalmethodshavebeenintensivelyappliedtoavarietyofscientificresearchesandengi-neeringdesigns.Althoughthecomputationalfluiddynamics(CFD)methodhasplayedadominantroleinstudyingandsimu-latingtransportphenomenainvolvingfluidflowandheatandmasstransfers,inrecentyears,othernumericalmethodsforthesimulationsatmeso-andmicro-scaleshavealsobeenactivelyappliedtosolvethephysicsofcomplexflowandfluid-interfaceinteractions.Thispaperpresentsareviewofrecentadvancesinmulti-scalecomputationalsimulationofbiomimeticsrelatedfluidflowproblems.Thestate-of-the-artnumericaltechniques,suchaslatticeBoltzmannmethod(LBM),moleculardynamics(MD),andconventionalCFD,appliedtodifferentproblemssuchasfishflow,electro-osmosiseffectofearthwormmotion,andself-cleaninghydrophobicsurface,andthenumericalapproachesareintroduced.Thenewchallengingofmodellingbiomi-meticsproblemsindevelopingthephysicalconditionsofself-cleanhydrophobicsurfacesisdiscussed.

简介：大雨的三维的风领域在2005年6月12-13日与位于Meizhou和Shantou的城市的dual-Doppler雷达的卷扫描数据在广东省被检索并且学习。这被显示出中央--规模和中央--在低、中间的层位于对流系统的规模集中线在重降雨起一个重要作用。集中线是雨的开始并且维持的机制。三个维的运动学的结构模型也被给。

简介：在全球放的系统(GPS)遥感技术的最近的进展允许从推迟的信号的可降水蒸汽(PWV)的一个直接评价由GPS卫星播送了，它能被吸收进数字模型与四维变化(4DVAR)数据吸收。一个中央缩尺模型和它的4DVAR系统被用来存取吸收GPS-PWV并且时时的影响降雨观察在上短期一个重降雨事件的预言在2002年6月20日。重降水被中央的一个序列导致--β-在中国沿着mei-yu前面放大对流系统(MCS)。有GPS-PWV吸收的实验成功地模仿了观察MCS簇的进化并且也消除了没有4DVAR吸收，在实验发现的错误的降雨系统。实验与时时，降雨吸收在MCS开始的预言和错误的系统的消除上两个都同样表现了，然而，比它很快很驱散的MCS在观察做了。导致吸收的潮湿不安和中央可伸缩，这被发现低级喷气对MCS产生和发展有用。假严肃波浪可以为当前的4DVAR算法张贴严肃的限制，这也被发现，它将降级吸收效率，特别为降雨数据。有不同观察，吸收窗户和观察的敏感实验称叮当响建议那吸收GPS-PWV能是相当有效的，甚至与象1h一样短的吸收窗户。在另一方面，吸收降雨观察要求观察的选择上的小心称的极端叮当响，假严肃的控制飘动。

简介：Theaimofthisstudyistodevelopdatacollectiontoolsforevaluationofschoolpracticecoursesandforperceptionsofteachercandidatesregardingteachercompetenciesforeffectiveteaching.Threehundredandeighty-eightlastyearundergraduatestudentsfromsevenprogramsoffacultiesofeducationattwostateuniversitiesparticipatedinthestudy.Itemsofthe5-pointLikertscalewerewrittenaccordingtothedimensionsoftheconstructswithrespecttotherelatedliterature.Theitemswerereviewedbythreeexperts,oneofwhomisintheeducationalmeasurementandtwoofwhomareinthescienceandbiologyeducationdepartments.Dimensionalitiesofthetwo-dimensionalEvaluationofPracticumScale（EPS）andone-dimensionalCompetencyofInstructionQualityScale（CIQS）wereanalyzedusingfactoranalysis.UnweightedleastsquaresestimationmethodandPromaxrotationwereusedinthefactoranalysisprocedures.Cronbach＇sacoefficientswere0.89and0.83forthetwodimensionsofEPSand0.82forCIQS.

简介：在《英文角斗场》中,每篇文章都是精选自英美中小学生的读物和教材噢。想知道自己的英语水平有多高,就来试试吧。

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简介：由灾害天气国家重点实验室数值预报研究部开发的区域中尺度数值预报系统（GRAPES_Meso）经过国家气象中心一年多的连续实时业务试验运行，达到了项目的指标要求，系统运行稳定，预报效果较现有的区域数值预报系统（HLAFS025）有明显改进。2006年7月，GRAPES_Meso通过了由中国气象局组织的业务运行专家评审。2006年7月26日，中国气象局正式批准GRAPES_Meso投入业务运行，同时停止运行HLAFS025业务系统，

简介：I-IntroductionTheNeo-BabyloniantextUETVII,1261,publishedbythelateProfessorO.R.Gurney,showsthatin1.42afourth-stringislisted,bilingually,asSumerian'sa4.tur'='fourth,small-string',andAkkadian'a-ba-nu-[u]'='Ea-created'.Itistheonlytheonumericstringmentionedinthetext.ThepairingofEawiththisfourthstringwhilstthegodisusuallyassociatedwithnumber403attractedmy

简介：Longtermmorphologicalsimulationsusingcompletecoupledmodelsleadtoverytimeconsumingcomputations.Latteux(1995)presentedmodellingtechniquesdevelopedfortidalcurrentsituationsinordertoreducethecomputationaleffort.Inthispapertheapplicabilityofsuchmethodstosmallscaleproblemsisinvestigated.Itispointedoutthatthesemethodscanbetransferredtosmallscaleproblemsusingtheperiodicityofthevortexsheddingprocess.

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简介：Frommethylpyropheophorbide-a(MPPa,1),thevinylgroupofmethylpyropheophorbide-awasconvertedintoalkylcarbonylgroupbyGrignardreactionandoxidizationtogivechlorins2,3and5.TheVilsmeierreactionofnickel3-substituent-3-devinylpyropheophorbide-a(6),whichwaspreparedbythemetallationwithnickelacetate,with3-dimethylamino-acrolein/phosphorylchloride(3-DMA/POCl3)wascarriedouttogiveδ-meso-formylvinylpyropheophorbide-a(7)ingoodyield.Thebenzoisobacterichlorin(8)wasobtainedbythetreatmentof7bwithconcentratedsulfuricacid.

简介：证明了正则空间中闭Lindelof映射逆保持序列式meso紧性，从而改进了MancusoVJ关于正则空间中完备映射逆保持meso紧性这一结果；进一步我们指出定理条件中原象空间的正则性不可被省略而象空间的正则性可以用原象空间的正规性来替代．

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