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简介：Thisstudyinvestigatedcharacteristicsofbifurcationandcriticalbucklingloadbyshapeimperfectionofspacetruss,whichweresensitivetoinitialconditions.Thecriticalpointandbucklingloadwerecomputedbytheanalysisoftheeigenvaluesanddeterminantsofthetangentialstiffnessmatrix.Thetwo-free-nodesexampleandstardomewereselectedforthecasestudyinordertoexaminethenodalbucklingandglobalbucklingbythesensitivitytotheeigenbucklingmodeandtheanalysesoftheinfluence,andcharacteristicsoftheparametersasdefinedbytheloadratioofthecenternodeandsurroundingnode,aswellasrise-spanratiowereperformed.Thesensitivitytotheimperfectionoftheinitialshapeofthetwo-free-nodesexample,whichoccursduetosnappingatthecriticalpoint,resultedinbifurcationbeforethelimitpointduetothebucklingmode,andthebucklingloadwasreducedbytheincreaseintheamountofimperfection.Thetwosensitivebucklingpatternsofthenumericalmodelareestablishedbyinvestigatingthedisplacedpositionofthefreenodes,andtheasymmetriceigenmodegreatlyinfluencedthebehavioroftheimperfectionshapewhetheritwasatlimitpointorbifurcation.Furthermore,thesensitivemodeofthetwo-free-nodesexamplewassimilartothein-extensionalbasismechanismofasimplifiedmodel.Thestardome,whichwasusedtoexaminetheinfluenceamongseveralnodes,indicatedthattheinfluenceofnodalbucklingwasgreaterthanthatofglobalbucklingastherise-spanratiowashigher.Besides,globalbucklingisoccurredwithreachingbifurcationpointasthevalueofloadratiowashigher,andthebucklingloadlevelwasabout50%-70%ofloadlevelatlimitpoint.

简介：Yishu差错地区(Tanlu差错地区中间片断)在Presinian被形成。周期的构造活动和强壮的地震事件沿着差错地区发生了。在古苏格兰的运动的起始的阶段期间，与从Yishupaleo隧道海洋的违反继续到西方的山东，不平的厚沉积，主要沙，泥和碳酸盐创作了沿岸，泻湖，和浅海的外形，在Yishu差错地区和西方的山东被扔，并且构造了底部部分Liguan和Zhushadong形成的更低的寒武纪的在于。通过地观察和实验室考试，各种各样的paleoseismic记录在Liguan形成和Yishu差错地区和它的附近的Zhushadong形成被发现了，包括有被强烈地震触发的syn沉积的变丑结构的一些层(即seismite，seismo-olistostrome，和seismo-turbidite)。在Zhushadong形成开发的Paleoseismic记录主要是有软沉积的变丑结构的seismites，例如液化挤入构造，小液化碳酸盐的石灰泥火山，液化静脉，液化角砾岩，旋绕变丑(地震褶层)，分级的差错，软硅质的静脉，和变丑stromatolite，象有semiconsolidated沉积的易碎的变丑结构的seismites一样。在Liguan形成保存的Paleoseismic记录是有商业萧条的不仅seismo-olistostrome褶层，负担结构，和ball-and-pillows，而且有卷绕旋转床上用品的seismo-turbidite，分级的床上用品并且起浪床上用品。然而在西方的山东区域，越离Yishu差错地区靠近，越greaterLiguan形成的厚度和Zhushadong形成，越多更大有paleoseismic的层的数字和类型记录，并且更高，地震紧张由地震记录的协会思考了。这条证据显示强烈地震事件伴随的构造taphrogenesis在古苏格兰的运动的起始的阶段期间发生在Yishu差错地区，它在那时间沿着Paleo-Tanlu差错地区表达了中国朝鲜语的板的分散。

简介：Adimpleappearsonafreesurfacewhilerotatingacylindertankfilledwithliquid.Thedimplestartstoconcentricallydeepertoadrainportatthebottomcenterofthetank.Overtime,thedimplepenetratesthedrainport,afreesurfaceformsalongandslenderstringshapeinthetank,andaso-calledvortexing(aircore)phenomenonoccurs.Thegenerationofavortexcoredependsonthesizeofthetankanddrainport,andonthepropertiesoftheliquidinthetank.Inthisstudy,theliquidlevelandthetimeatwhichthevortexcoreisinitiallygeneratedarenumericallyinvestigatedusingdifferentvaluesoftankdiameter,drainportdiameter,andinitialtankrotationalspeeds.Insteadofafullthree-dimensionalanalysis,atwo-dimensionalaxisymmetricsimulationisconducted.Themomentumconservationequationinthecircumferentialdirectionisadditionallysolvedinthetwo-dimensionalmeshsystem.Severalnon-dimensionalvariablesarecreated:theratiooftheaircoregenerationdistanceandtankdiameter,thediameterratioofthetankanddrainport,therotationalReynoldsnumber,therotationalFroudenumber,andtherotationalWebernumber.Finally,thenon-dimensionalaircoregenerationdistanceiscorrelatedwiththeothernon-dimensionalparameters.