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：Inthispaper,thefeedbackloadreductionprobleminwirelesssystemsbasedonorthogonalfrequencydivisionmultiplexing(OFDM)isinvestigatedandanopportunisticfeedbackscheme(OFS)isproposed.ThekeyideabehindOFSisthatonlythekeychannelgainswhichcansignificantlyaffectthesystemthroughputarefedbacktotheBS.Firstly,thekeychannelgainsareprovedtobelongtoachannelgaininterval.Secondly,astatisticalmethodisproposedtoestimatethechannelgaininterval.Thirdly,theopportunisticfeedbackschemeisformulatedandthefeedbackloadofOFSisanalyzed.TheadvantageofOFSisthreefold:thefirstisOFScanworkinbothOFDM-basedmulticastsystemandOFDM-basedunicastsystem.ThesecondisthechannelfadingtypeoftheBS-userlinkisnotrequired,whichismorerealistic.ThethirdisOFScangetbetterfeedbackloadperformancecomparedwithotherschemes,whileachievingalmostthesamethroughputperformancecomparedwiththatoffullfeedbackscheme.

简介：InvehicleAd-hocnetwok(VANET),trafficloadisoftenunevenlydistributedamongaccesspoints(APs).Suchloadimbalancehampersthenetworkfromfullyutilizingthenetworkcapacity.Toalleviatesuchimbalance,thepaperintroducesanovelpricinggamemodel.Theresearchsceneisattheintersectionwhenthetrafficlightisgreen.Asvehiclesarehighlymobileandthenetworktypologychangesdynamically,thepaperdividesthegreenlighttimeintoequalslotsandcalculatesAPs'priceswiththepresentedpricinggameineachtimeslot.Thewholeprocessisarepeatedgamemodel.ThefinalequilibriumsolutionsetisAPs'pricingstrategy,andthepaperclaimthatthisequilibriumsolutionsetcanaffectvehicles'selectionandensureAPs'load-balancing.Simulationresultsbasedonarealisticvehiculartrafficmodeldemonstratetheeffectivenessofthegamemethod.

简介：Thisworkpresentsanewanalyticalmethodtoanalyzetheinfluenceofreactionpilesonthetestpileresponseinastaticloadtest.Inourmethod,theinteractiveeffectbetweensoilandpileissimulatedusingindependentspringsandthesheardisplacementmethodisadoptedtoanalyzetheinfluenceofreactionpilesontestpileresponse.Moreover,theinfluenceoftheshelteringeffectbetweenreactionpilesandtestpileonthetestpileresponseistakenintoaccount.Twocasesareanalyzedtoverifytherationalityandefficiencyofthepresentmethod.Thismethodcanbeeasilyextendedtoanonlinearresponseofaninfluencedtestpileembeddedinamultilayeredsoil,andthevalidityisalsodemonstratedusingcentrifugemodeltestsandacomputerprogrampresentedintheliterature.Thepresentanalysesindicatethattheproposedmethodwillleadtoanunderestimationofthetestpilesettlementinastaticloadtestiftheinfluenceofthepresenceofreactionpilesonthetestpileresponseisneglected.

简介：ThepresentpaperinvestigatesthedynamicresponseoffiniteTimoshenkobeamsrestingonasixparameterfoundationsubjectedtoamovingload.ItisforthefirsttimethattheGalerkinmethodanditsconvergencearestudiedfortheresponseofaTimoshenkobeamsupportedbyanonlinearfoundation.ThenonlinearPasternakfoundationisassumedtobecubic.Therefore,theefectsofthesheardeformablebeamsandthesheardeformationoffoundationsareconsideredatthesametime.TheGalerkinmethodisutilizedfordiscretizingthenonlinearpartialdifferentialgoverningequationsoftheforcedvibration.ThedynamicresponsesofTimoshenkobeamsaredeterminedviathefourth-orderRunge–Kuttamethod.Moreover,theefectsofdiferenttruncationtermsonthedynamicresponsesofaTimoshenkobeamrestingonacomplexfoundationarediscussed.ThenumericalinvestigationsshowsthatthedynamicresponseofTimoshenkobeamssupportedbyelasticfoundationsneedssuperhigh-ordermodes.Furthermore,thesystemparametersarecomparedtodeterminethedependenceoftheconvergencesoftheGalerkinmethod.

简介：Forafinitebeamwithanonzerogapdistance,anasymmetricconcentratedloadcanbeeitherinsideoroutsideofthecontactzone.Anewgoverningequationisgivenforthecaseofaconcentratedloadoutsidethecontactzone.Bynumericallysolvingtheleft-sideandright-sidecontactlengthsofthebeam,acriterionisestablishedtodeterminewhethertheconcentratedloadisinsideoroutsidethecontactzone.Amoregeneralapproachonthetensionlesscontactofabeamisthuspresented.

简介：FieldexperimentswereconductedontotalloadtransportintheChelichayRiverBasin,amountainouscatchment(1,400km~2)locatedinnortheasternofIran,toevaluatetotalloadformulasincludingfourgravelbedriversandasandbedriver(QaresooRiver).GravelbedriversinChelichayRiverBasincanbegroupedintotwotypes;steepsloperiverswithhighshearvalues(ChehelchayRiverandKhormalooRiver)andmildsloperiverswithlowshearvalues(NarmabRiverandSoosaraRiver).Twodepthintegratingsuspendedloadsamplers(DH-48andD-49),andtwobedloadsamplers(Helley-SmithandBLSH)wereusedtomeasuretotalload.Theperformanceistestedof8totalloadtransportformulaeincluding4macroscopicand4microscopicmethods.Asystematicandthoroughanalysisof59setsofdatacollectedfromsandbedriverindicatethatYangandEngelundandHansenreachtothebetterresults,andfromfourgravelbedriversconfirmedthatthemethodsofKarimandKennedyandEngelundandHansenyieldsthebestresultsforsteepsloperivers,andthemethodsofEinsteinandBijkerarerankedhighestingradualsloperivers.

简介：为了调查autoclaved的地震行为，给忍受负担的石工技术墙(AACLMW)，没有构造上的措施的一面控制块墙和五块与不同构造上的措施围的水泥充气了被测试在下面低颠倒的周期的装载它模仿了对中等地震力量低。有不同构造上的措施的AACLMW的地震行为以失败模式，hysteretic曲线，变丑能力和排水量韧性被学习并且与那相比没有构造上的措施。试验性的结果显示包括构造上的柱和水平具体脱衣的构造上的措施为改进AACLMW的地震行为是有效的。在这份报纸的学习以后能为进一步的分析和AACLMW的工程申请提供一个可靠试验性的基础。

简介：Thispaperdealswiththedesignofanoutputfeedbackpredictivecontrollerforinductionmotors.Thefundamentalinterestoftheproposedcontrolleristhecapabilityofdecouplingthemechanicalspeedandtherotorfluxes,withoutdegradationagainstthevariationofrotorresistanceandloadtorque.Hence,thecontributionistoapplytwoestimationproceduresinordertoachievethisgoal.Namely,anunknowninputobserver（UIO）isusedfortheconstanttimeestimationwhereasaheuristicsolutionisexploitedfortheloadtorqueupdate.Moreover,rotorfluxcomponentsarerecoveredasanunavailablestateofthesystem.Effectivenessoftheproposedobserversandtheperformanceofthecontrollerareconfirmedbysimulationresults.