简介：Theformationofsandwaveissuchaprocessinwhichtheroughnessanddiscontinuityoftheoriginalbedsurfacecausethedisturbanceofthebottomlaminarflowinanopenchannel,andthedevelopmentofthedisturbanceinturnleadstoinstabilityoftheflowandtheappearanceofthecoherentstructure.Theevolutionanddevelopmentofthecoherentstructurefurtherpromotetheundulationsofbedsurfaceandsandwavesrisefinally.Thesandwaveisexplainedasaresultofactionthatthebedsedimentparticlesaredisturbedbythecoherentstructure.Thisstudyshowsthatthesandwaveformationistheresultofdisturbanceactionofneutralcoherentstructure,andthesandwaveshapeobtainedincomputationsisidenticaltothepracticalone.

简介：Ahybridanalysismethodintimeandfrequencydomainsforlinearsoil-structureinteractionispresented.First,thetimedomainsolutionofthesystemwithRayleighdampingexcitedbyashorttimeimpulseisobtainedbythedecouplingnumericalsimulationtechniqueofnear-fieldwavemotion.Then,thecorrespondingfrequencydomainsolutioncanbegotbyFouriertransform.Accordingtotherelationshipbetweendampingvalueanddynamicre-sponseofasystem,thesolutionofthesystemwithcomplexdampingcanbegotbyTaylorexpansion.Thehybridmethodmakesthebestofdecouplingandexplicitalgorithmintimedomain,andincreasesthecalculationefficien-cyforlinearsoil-structureinteractionanalysis.

简介：TherigidcentralbuckleemployedintheRunyangSuspensionBridge(RSB)wasthefirsttimeitwasusedinasuspensionbridgeinChina.ByusingaspectralrepresentationmethodandFFTtechniquecombinedwithmeasureddata,a3Dfluctuatingwindfieldconsideringthetowerwindeffectissimulated.AnovelFEmodelforbuffetinganalysisisthenpresented,inwhichaspecificuser-definedMatrix27elementinANSYSisemployedtosimulatetheaeroelasticforcesanditsstiffnessordampingmatricesareparameterizedbywindvelocityandvibrationfrequency.Anonlineartimehistoryanalysisiscarriedouttostudytheinfluenceoftherigidcentralbuckleonthewind-inducedbuffetingresponseofalong-spansuspensionbridge.Theresultscanbeusedasareferenceforwindresistancedesignoflong-spansuspensionbridgeswitharigidcentralbuckleinthefuture.

简介：二强烈伪线性的mesoscale在北中国的对流系统(QLMCS)用WRF被模仿(天气研究并且预报)模型和3D-Var(三维变化)ARPS(先进地区性的预言系统)的分析系统模型。闪电密度是的一个新在方法计算了使用降水和非降水冰质量被开发揭示在闪电活动和QLMCS结构之间的关系。结果显示与用二个以前的方法计算结果相比，闪电密度计算了使用在这研究介绍的新方法在有观察的更好的一致。用新方法基于计算闪电密度，最，闪电活动在右边上并且在QLMCS的前面被开始，这被发现，在表面风领域强烈地收敛了的地方。披肩比到背在向东南的进行QLMCS前是强壮得多的它，和他们的闪电事件主要与披肩的一个大坡度发生在区域。在闪电和非闪电区域之间的比较显示闪电区域比非闪电区域展示了更多的强烈上升运动；在闪电和非闪电区域之间的最大的反射率的垂直范围是很不同的；并且混合比率的冰没展示闪电和非闪电区域之间的重要差别。

简介：Inthispaper,thecharacteristicsofdifferentformsofmildslopeequationsfornon-linearwaveareanalyzed,andnewnon-lineartheoreticmodelsforwavepropagationarepresented,withnon-lineartermsaddedtothemildslopeequationsfornon-stationarylinearwavesanddissipativeeffectsconsidered.Numericalsimulationmodelsaredevelopedofnon-linearwavepropagationforwatersofmildlyvaryingtopographywithcomplicatedboundary,andtheeffectsarestudiedofdifferentnon-linearcorrectionsoncalculationresultsofextendedmildslopeequations.Systematicalnumericalsimulationtestsshowthatthepresentmodelscaneffectivelyreflectnon-lineareffects.

简介：The3-hour-intervalpredictionofground-leveltemperaturefrom+00houtto+45hinSouthKorea(38stations)isperformedusingtheDLM(dynamiclinearmodel)inordertoeliminatethesystematicerrorofnumericalmodelforecasts.NumericalmodelforecastsandobservationsareusedasinputvaluesoftheDLM.AccordingtothecomparisonoftheDLMforecaststotheKFM(Kalmanfiltermodel)forecastswithRMSEandbias,theDLMisusefultoimprovetheaccuracyofprediction.

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简介：ThispaperexaminestheexperimentalstudyoninfluenceofmaterialcomponenttononlinearrelationbetweensedimentyieldanddrainagenetworkdevelopmentcompletedintheLab.Theareaofflumedrainagesystemis81.2m2,thelongitudinalgradientandcrosssectionslopearefrom0.0348to0.0775andfrom0.0115to0.038,respectively.Differentmodelmaterialswithamediumdiameterof0.021mm,0.076mmand0.066mmcoverthreeexperimentseach.Anartificialrainfallequipmentisasprinkler-systemcomposedof7downwardnozzles,distributedbyhexagontypeandagivenrainfallintensityis35.56mm/hr.cm2.Threeexperimentsaredesignedbyprocess-responseprincipleatthebeginningtheψshapedsmallnetworkisdugintheflume.Runningtimespansare720m,1440minutesand540minutesforRunsⅠ,ⅣandⅥ,respectively.Threeexperimentsshowthatthesedimentyieldprocessesarecharacterizedbydelayingwithavibration.Duringnetworkdevelopmenttheenergyofadrainagesystemisdissipatedbytwoways,ofwhichoneisincreasingthenumberofchannels(rillandgully),andtheotheroneisenlargingthechannellength.Thefractaldimensionofadrainagenetworkisexactlyanindexofenergydissipationofadrainagemorphologicalsystem.Changeofthisindexwithtimeisanunsymmetricalconcavecurve.Comparisonofthreeexperimentsexplainsthatthevibrationandthedelayingratioofsedimentyieldprocessesincreasewithmaterialcoarsening,whilethenumberofchanneldecreases.Thelengthofchannelenlargeswithmaterialfining.Thereexistsnon-linearrelationshipbetweenfractaldimensionandsedimentyieldwithanunsymmetricalhyperboliccurve.Thebsolutevalueofdelayingratioofthecurvereduceswithtimeunningandmaterialfining.Itischaracterizedbysubstitutionofsituationtotime.

简介：为有在出现在所有团中的控制输入隧道和参数无常的时间延期的电镀物品水力的激活的结构的系统的一个类的柔韧的活跃颤动控制的问题，抑制并且僵硬矩阵在这份报纸被调查。由介绍一个线性变化参数，首先，非线性的系统被描述为变化的一个线性参数(LPV)模型。基于这个LPV模型，第二，为asymptotically要稳定的系统的一个基于LMI的条件被推出。由解决这些LMI，一个参数依赖者控制器为与骚乱变细的规定水平稳定的closedloop系统被建立。条件也被扩大到不明确的案例。最后，一些数字模拟表明建议控制器的令人满意的表演。

简介：一系列线性稳定性分析面对粘性，热传导性和expansivity的空间变化在热传送对流的发作上被执行。我们考虑附加到静电干扰的无穷小的不安的时间的进化(不动)并且在加热basally的平面层的传导性的状态。从在有增加粘性的温度依赖的振幅的流动模式的变化，我们识别了转变进停滞盖(圣)政体，在传送对流在仅仅下面发生的地方一在最高的表面的冷液体厚、停滞盖。详细分析在空间变化在热电导率或expansivity导致的圣政体显示出传送对流房间的方面比率的重要增加：圣传送对流的水平长度规模能被多达50%与深度随热电导率的10次增加扩大。我们进一步开发了成功地复制了在物理性质为给定的空间变化增加圣政体传送对流房间的水平长度规模的机制的圣传送对流的一个分析模型。我们的调查结果可以在披风在传送对流模式上加亮热电导率的空间变化的必要角色。

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