简介:本文较为详细地介绍了如何通过wingate代理软件,来共享cablemodem宽带上网的安装与配置操作.因它源于实践中摸索出的经验,因此具有较好的实用价值.
简介:Theapproximateeigenfrequenciesforthein-planevibrationsofacablestruc-tureconsistingofinclinedcables,togetherwithpointmassesatvariouspointswerecom-puted.Itwasdiscoveredthattheclassicaltransfermatrixmethodwasinadequateforthistask,andhencethelargerexteriormatriceswereusedtodeterminetheeigenfrequencyequation.Thenpredictionsofthedynamicsofthegeneralcablestructurebasedontheasymptoticestimatesoftheexteriormatricesweremade.
简介:TheREapplicationinaluminumbasealloy,auniquebranchofREapplicationinmetallurgyinChi-na,hasdevelopedrapidly.Boththeoutputandtech-niqueareinaleadingpositionintheworld.Particular-ly,theREapplicationinpowertransmissioncablehasmadeaconsiderableprogress.UptonowChinacanfabricatethreekindsofRE-containingconductors.Oneisahighconductivitycon-ductor;theothertwoarehighstrengthandheat-re-
简介:Boththeinplaneandout-of-planetransversevibrationsofaviscoelasticcablesubjectedtoaninitialstressdistributinguniformonthecrosssectionarestudied.Theconstitutionofthecablematerialisas-sumedtobeofthehereditaryintegraltype.Thepartialdifferential-integralequationsofmotionarederivedfirst.ThenbyapplyingGalerkin’smethod,thegoverningequationsarereducedtoasetofsecond-ordernon-lineardifferential-integralequationswhicharesolvedbyfinitedifferencenumericalintegrationprocedures.Finally,theeffectsoftheviscosityparameterandtheelaslicparameteronthetransientamplitudesofthefirstmodeareinvestigatedbynumericalsimulation.
简介:AsimplifiedfragilityanalysisoffantypecablestayedbridgesusingProbabilisticRiskAnalysis(PRA)procedureispresentedfordeterminingtheirfailureprobabilityunderrandomgroundmotion.Seismicinputtothebridgesupportisconsideredtobeariskconsistentresponsespectrumwhichisobtainedfromaseparateanalysis.Fortheresponseanalysis,thebridgedeckismodeledasabeamsupportedonspringsatdifferentpoints.Thestiffnessesofthespringsaredeterminedbyaseparate2Dstaticanalysisofcable-tower-decksystem.Theanalysisprovidesacoupledstiffnessmatrixforthespringsystem.Acontinuummethodofanalysisusingdynamicstiffnessisusedtodeterminethedynamicpropertiesofthebridges.Theresponseofthebridgedeckisobtainedbytheresponsespectrummethodofanalysisasappliedtomultidegreeoffreedomsystemwhichdulytakesintoaccountthequasi-staticcomponentofbridgedeckvibration.Thefragilityanalysisincludesuncertaintiesarisingduetothevariationingroundmotion,materialproperty,modeling,methodofanalysis,ductilityfactoranddamageconcentrationeffect.ProbabilityoffailureofthebridgedeckisdeterminedbytheFirstOrderSecondMoment(FOSM)methodofreliability.Athreespandoubleplanesymmetricalfantypecablestayedbridgeoftotalspan689m,isusedasanillustrativeexample.Thefragilitycurvesforthebridgedeckfailureareobtainedunderanumberofparametricvariations.Someoftheimportantconclusionsofthestudyindicatethat(i)notonlyverticalcomponentbutalsothehorizontalcomponentofgroundmotionhasconsiderableeffectontheprobabilityoffailure;(ii)groundmotionwithnotimelagbetweensupportexcitationsprovidesasmallerprobabilityoffailureascomparedtogroundmotionwithverylargetimelagbetweensupportexcitation;and(iii)probabilityoffailuremayconsiderablyincreaseforsoftsoilcondition.
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简介:Three-dimensionalnonlinearaerodynamicstabilityanalysiswasappliedtostudytheaerodynamicstabilityofacable-stayed-suspension(CSS)hybridbridgewithmainspanof1400meters,andtheeffectsofsomedesignparameters(suchasthecablesag,lengthofsuspensionportion,cableplanearrangement,subsidiarypiersinsidespans,thedeckform,etc.)ontheaerodynamicstabilityofthebridgeareanalyticallyinvestigated.Thekeydesignparameters,whichsignificantlyinfluencetheaerodynamicstabilityofCSShybridbridges,arepointedout,andbasedonthewindstabilitythefavorablestructuralsystemofCSShybridbridgesisdiscussed.
简介:<正>Accordingtopressreports,China’sfirstlongdistance,extra-highvoltagecableisexpectedtocrossQiongzhouStraitsbefore2006.
简介:Inisnecessarytostudydynamicoperationefficiencyoftransmissionnetworksinordertorealizehighintensificationofcommunicationnetworks.Theoperationefficiencydiscussedhereshouldexistnotinlogic-circuitlayer,butalsoinbothpathlayerandmediumlayer.Atheoreticalmethodofthemeasurementoflayersanscomprehensiveevaluationsispresentedbasedontheconceptoftransmissionefficiency.
简介:Inordertoresolvethetrafficcongestionproblem,manycable-stayedbridgesaredesignedwithalargewidthtospanratio.Thisresultsinsignificantshearlageffecttocausenonuniformstressdistributionalongtheflangesofthebeamofbridge.ThispaperreportsstudyontheshearlageffectoftheLanzhouXiaoxihuYellowRiverBridge.A3Dfiniteelementmodelofthebridgewasdevelopedandfiniteelementanalysis(FEA)wasdonetoobtainthetheoreticalresults.Toevaluatethetheoreticalresults,ascaledmodelwasmadetoconductstatictestinlaboratory.TheexperimentresultsaccordedwiththeresultsobtainedbyFEA.ItisprovedthatFEAisaneffectivemethodtopredictshearlageffectofbridgesofthistype.