简介：ThestudywasmadebyobservingtheannualchangeofthegonadaldevelopmentofamphioxusinXiamencohtinuouslyfortwoyearsfromNovember,1986toNovember,1988.Wedeterminedthegonadaldiameter,gonadosomaticindexofeachamphioxus,andobservedthehistologicalcharacteristicofthegonadaldevelopmentofthefemaleandmalebycutsection,whichprovidedthebasisfordividingthestagesgonadsandthedetermininglevelofthegonadaldevelopmentofamphioxusineachmonth.

简介：Fortheglobalandstructuralfatiguestrengthanalysisofasemi-submersibleplatform,waveloadsunderdesigncon-ditionsarecalculatedbyuseofthethree-dimensionalboundarydementmethod.Methodsforcalculatingtheforward-speedfree-surfaceGreenfunctionarediscussedandacomputerprogramwiththisGreenfunctionisdeveloped.Accordingtothespecialrules,thewaveloadsunderseveraltypicaldesignconditionsoftheplatformarecalculated.Themaximumverticalbendingmoment,torsionmomentandhorizontalsplitforcearedeterminedfromaseriesofcontourmapsofwaveloadsforthewaveperiodof5to18secondsatacertainintervalandthewavephaseofO°to360°atacertaininterval.Thewaveheightisdeterminedbythefunctionofwaveperiodwithagivenexceedanceprobability.Themaximumwaveloadsunderthecombinationofwaveparametersareusedastheinputofhydrodynamicpressureinthethree-dimensionalfiniteelementanalysisprocess.Thetransferfunctionsofwaveloadsontheplatformareusedforthefatiguestrengthanal-ysisoftheK-tubularjointandthesub-modelofthestructure.

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简介：—Thepresentstudyinvestigatestheinteractionofsteepwaveswithsemi-circularbreakwaterwiththecomplexplane＇sCauchyboundaryintegraltheorem.Theboundaryintegralmethodisusedtotransformthecalculationinfluiddomainintoitsboundaryalone.Inthecalculationthecomputationdo-mainismovedwiththepropagationofwaves.AnumericalsolutionisobtainedforincidentStokeswavespassingthesubmergedobstacles.Thismethodhasbeenextendedtothecalculationofwaverun-uponaslopeforestimatingwaveovertopping.

简介：Inthispaper,anewdefinitionofstructuresystemredundancyisproposedinviewofthevariousmeasuresforstructureredundancy.Byintroducingthetermsofstructuresystemfailureatthemechanismlevelandequivalentreliabilityindex,thesafetyforexistingoffshoreplatformscanbeevaluatedbythesemi-probabilisticmethodpresentedinthispaper.Somenumericalexamplesaregivenandsatisfactoryresultshavebeenobtained.

简介：流动和海水汇率为回收并且挖出工作被安排的一个围住半的浅海湾用atwo维的数字模型和一个Lagrangian方法被预言了。流动和强调的材料运输过时的人或物上的风效果，和风的三十年的平均值在数字模拟被考虑了。总体上，甚至在回收并且挖出被进行以后，流动模式看起来类似于原来的国家。然而，直到20%～100%的速度变化出现在构造区域的附近。在强迫的夏天风的情况中，在回收并且挖出，，以后的从71.6%～82.9%的海水汇率增加由particle-trackingmethod显示了。在强迫的冬季风的情况中，相反，海水汇率看起来在自然条件下面是97.2%，但是在回收并且挖出以后稍微减少到93.2%。因此，强迫的风在控制海水汇率起一个重要作用。如果挖出同时与回收被执行，Theseawater汇率被15%进一步改进。这建议挖出的罐头是一个有效工具减轻流动的变化。

简介：—Theresultsofdesignandexperimentofasubmergedsemi-circularbreakwaterattheYangtzeestuaryshowthatthesubmergedstructurewillbeunsafewhenthegeneralempiricalwaveforceformulaforsemi-circularbreakwaterisusedindesign.Therefore,anewcalculationmethodforthewaveforcesact-ingonasubmergedsemi-circularstructureisgiveninthispaper,inwhichthewaveforceactingonthein-sidecircumferenceofsemi-circulararchisincluded,andthephasemodificationcoefficientinthegeneralempiricalformulaisadjustedaswell.Thenewwaveforcecalculationmethodhasbeenverifiedbythere-sultsofsevenrelatedphysicalmodeltestsandadoptedinthedesignofthesouthesturaryjettyofthefirststageprojectofDeepChannelImprovementProjectoftheYangtzeRiverEstuary,thetotaljettylengthbe-ing17.5km.

简介：ＮｏｔｅｓＯｎｔｈｅｆｅａｔｕｒｅｓｏｆｔｈｅＳＳＴａｎｎｕａｌｃｙｃｌｅａｎｄｓｕｒｆａｃｅｈｅａｔｂｕｄｇｅｔｉｎｔｈｅＳｏｕｔｈＣｈｉｎａＳｅａＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅａｎｎｕａｌｃｙｃｌｅｉｎｔｈｅｏｃｅａｎａｎｄａｔｍｏｓｐｈｅｒｅｓ...

简介：ToinvestigatetheannualandinterannualvariabilityofoceansurfacewindovertheSouthChinaSea(SCS),thevectorempiricalorthogonalfunction(VEOF)methodandtheHilbert-Huangtransform(HHT)methodwereemployedtoanalyzeasetofcombinedsatellitescatterometerwinddataduringtheperiodfromDecember1992toOctober2009.ThemergedwinddataweregeneratedfromEuropeanRemoteSensingSatellite(ERS)-1/2Scatterometer,NASAScatterometer(NSCAT)andNASA'sQuickScatterometer(QuikSCAT)windproducts.ThefirstVEOFmodecorrespondstoawinter-summermodewhichaccountsfor87.3%ofthetotalvarianceandrepresentstheEastAsianmonsoonfeatures.ThesecondmodeofVEOFcorrespondstoaspring-autumnoscillationwhichaccountsfor8.3%ofthetotalvariance.Toanalyzetheinterannualvariability,theannualsignalwasremovedfromthewinddatasetandtheVEOFsoftheresidualswerecalculated.ThetemporalmodeofthefirstinterannualVEOFiscorrelatedwiththeSouthernOscillationIndex(SOI)withafour-monthlag.ThesecondtemporalinterannualVEOFmodeiscorrelatedwiththeSOIwithnotimelag.ThetimeseriesofthetwointerannualVEOFsweredecomposedusingtheHHTmethodandtheresultsalsoshowacorrelationbetweentheinterannualvariabilityandElNi?o-SouthernOscillation(ENSO)events.

简介：TheMultipleColumnPlatform(MCP)semi-submersibleisanewlyproposedconcept,whichdiffersfromtheconventionalsemi-submersibles,featuringcentrecolumnandmiddlepontoon.Itisparamounttoensureitsstructuralreliabilityandsafeoperationatsea,andarigorousinvestigationisconductedtoexaminethehydrodynamicandstructuralperformanceforthenovelstructureconcept.Inthispaper,thenumericalandexperimentalstudiesonthehydrodynamicperformanceofMCPareperformed.Numericalsimulationsareconductedinboththefrequencyandtimedomainsbasedon3Dpotentialtheory.Thenumericalmodelsarevalidatedbyexperimentalmeasurementsobtainedfromextensivesetsofmodeltestsunderbothregularwaveandirregularwaveconditions.Moreover,acomparativestudyonMCPandtwoconventionalsemi-submersiblesarecarriedoutusingnumericalsimulation.Specifically,thehydrodynamiccharacteristics,includinghydrodynamiccoefficients,naturalperiodsandmotionresponseamplitudeoperators(RAOs),mooringlinetensionarefullyexamined.ThepresentstudyprovesthefeasibilityofthenovelMCPanddemonstratesthepotentialpossibilityofoptimizationinthefuturestudy.

简介：Basedonthemonthlymeansealeveldataobtainedfrom3years′(1999-2001)tide-gaugemeasurements,theannualvariabilityofthesealevelnearQingdaoandJiaozhouBayisstudiedanddiscussedinthispaper.Resultsshowthattheseasurfaceheightatallthetidegaugesbecomeshigherinsummerthanthatinwinter,withanobviousseasonalvariability.Furthermoretheseasurfaceheightmeasuredatashortdistanceoutsidethebayislowerthanthatinthebay,showingaseasurfaceslopedownwardfromnorthtosouth.Thereasonsfortheformationoftheslopeareexplainedaswell,Thedynamicactionofthesummermonsoonandtheseasurfaceslope,andtheireffectsonthemonthlymeancurrentarestudiedbymeansofdynamicsprinciples.Theimportanceofthesummermonsoonandthepressuregradientgeneratedbytheseasurfaceslope,withtheireffectsonthealongshorecurrent,ispointedoutandemphasizedinthispaper.

简介：由于胭脂波浪的物理机制的复杂性，rogue-wavestructure相互作用问题的理论学习仍然取得很少进步。为常规形状的结构，然而，给理论分析是可能的，如果流氓波浪的一个相对简单的模型被使用。波浪负担，由作为胭脂波浪的一个直觉的基本模型被知道的一个集中的波浪导致了，在沉没半的柱体之上被学习经分解。集中的波浪由高斯信封波浪是近似的，包含流氓波浪的大多数特征的一个理想的模型。衍射速度潜力通过水平力量的流动地，和公式的分离被导出，弯曲时刻被建议。导出的公式适当地被简化，并且对数字结果通过比较验证了。另外，参数的影响集中的沉没深度和波浪例如集中的度，放，彻底地被调查。

简介：这份报纸地址关节风波浪导致了在正常状态和差错事件下面的近海的漂浮风汽轮机(OFWT)调节的一种半类型的动态回答。在这份报纸的分析及时被进行领域，用aero-hydro-servo-elastic模拟代码--快。由于唯一粘滞参考书系统的特征，实现在的原来的粘滞的抑制模型快被二次的代替获得精确俘获粘滞效果。模拟盒子在静止的水里包含免费腐烂的运动，面对常规波浪稳定运动并且象处于有或没有风的运作的海状态的动态反应一样弯屈。模拟也包括盒子因为快片在紧急情况以后投球导致的短暂回答关机。在许多刺激下面的站台运动，本地结构的负担和典型绳索行紧张力量的特征被获得并且调查。

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简介：Adesignofsemi-submersibleplatformismainlybasedontheextremeresponseanalysisduetotheforcesexperiencedbythecomponentsduringlifetime.Theexternalloadscaninducetheextremeairgapresponseandpotentialdeckimpacttothesemi-submersibleplatform.Itisimportanttopredictairgapresponseofplatformsaccuratelyinordertocheckthestrengthoflocalstructureswhichwithstandthewaveslammingduetonegativeairgap.Thewindloadcannotbesimulatedeasilybymodeltestintowingtankwhereasitcanbesimulatedaccuratelyinwindtunneltest.Furthermore,fullscalesimulationofthemooringsysteminmodeltestisstillatuffworkespeciallythestiffnessofthemooringsystem.Owingtotheabovementionedproblem,themodeltestresultsarenotaccurateenoughforairgapevaluation.Theaimofthispaperistopresentsensitivityanalysisresultsofairgapmotionwithrespecttothemooringsystemandwindloadforthedesignofsemi-submersibleplatform.Thoughthemodeltestresultsarenotsuitableforthedirectevaluationofairgap,theycanbeusedasagoodbasisfortuningtheradiationdampingandviscousdraginnumericalsimulation.Inthepresenteddesignexample,anumericalmodelistunedandvalidatedbyANSYSAQWAbasedonthemodeltestresultswithasimple4linesymmetricalhorizontalsoftmooringsystem.Accordingtothetunednumericalmodel,sensitivityanalysisstudiesofairgapmotionwithrespecttothemooringsystemandwindloadareperformedintimedomain.Threemooringsystemsandfivesimulationcasesaboutthepresentedplatformaresimulatedbasedontheresultsofwindtunneltestsandsea-keepingtests.Thesensitivityanalysisresultsarevaluableforthefloatingplatformdesign.

简介：Afullycoupled6-degree-of-freedomnonlineardynamicmodelispresentedtoanalyzethedynamicresponseofasemi-submersibleplatformwhichisequippedwiththedynamicpositioning(DP)system.Inthecontrolforcedesign,adynamicmodelofreferencelineardriftfrequencyinthehorizontalplaneisintroduced.Thedynamicsurfacecontrol(DSC)isusedtodesignacontrolstrategyfortheDP.Comparedwiththetraditionalback-steppingmethods,thedynamicsurfacecontrolcombinedwithradialbasisfunction(RBF)neuralnetworks(NNs)canavoiddifferentiatingintermediatevariablesrepeatedlyineverydesignstepduetotheintroductionofafirstorderfilter.LowfrequencymotionsobtainedfromtotalmotionsbyalowpassfilterarechosentobetheinputsfortheRBFNNswhichareusedtoapproximatethelowfrequencywaveforce.Consideringthepropellers’wearandtear,theeffectoffilteringfrequenciesforthecontrolforceisdiscussed.Basedonpowerconsumptionsandpositioningrequirements,theNNcentersaredetermined.Moreover,theRBFNNsusedtoapproximatethetotalwaveforcearebuilttomonitorthedisturbances.WiththeDPassistance,theresultsoffullycoupleddynamicresponsesimulationsaregiventoillustratetheeffectivenessoftheproposedcontrolstrategy.