简介:Environmentalloadistheprimaryfactorinthedesignofoffshoreengineeringstructuresandoceancurrentistheprincipalenvironmentalloadthatcausesunderwaterstructuralfailure.Incomputationalanalysis,thecalculationofcurrentloadismainlybasedonthecurrentprofile.Thecurrentprofilemodel,whichisbasedonastructuralfailurecriterion,isconducivetodecreasingtheuncertaintyofthecurrentload.Inthisstudy,weusedprototypemonitoringdataandtheempiricalorthogonalfunction(EOF)methodtoinvestigatethecurrentprofileintheSouthChinaSeaanditscorrelationwiththedesignofunderwaterstructuralstrengthandthedynamicdesignoffatigue.Theunderwaterstructuralstrengthdesigntakesintoaccountthesizeofthestructureandtheservicewaterdepth.Weproposeprofilesfortheoverallandlocaldesignsusingtheinversefirst-orderreliabilitymethod(IFORM).Weextractedthecharacteristicprofilecurrent(CPC)ofthemonitoredseaareatosolvedynamicdesignproblemssuchasvortex-inducedvibration(VIV).WeusedrandomsamplingtoverifythefeasibilityofusingtheEOFmethodtocalculatetheCPCfromthecurrentdataandidentifiedthemainproblemsassociatedwithusingtheCPC,whichdeservecloseattentioninVIVdesign.Ourresearchconclusionsprovidedirectreferencesfordeterminingcurrentloadinthisseaarea.Thisanalysismethodcanalsobeusedintheanalysisofotherseaareasorfieldvariables.
简介:摘要:新时期的物理教师不仅要教理论知识又要教研究问题的方法。不但要了解他人的研究成果,还要知道他们用什么方法建立理论体系的,初步学会和掌握物理 研究的基本方法。这样学生在以后的工作中,以这种方法为指导,减少工作的盲目性。本文主要阐述物理学家是在怎样的条件下采用什么方法研究问题的。