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10 个结果
  • 简介:Inthispaper,asingle-columnstructureusedaswell-headplatformisstudied.Theloadsofwaveandcurrentexertedonthesingle-columnwillbegreatlyreduced,thereforethecostofthestructurewillbedecreased.Theadvantagesofthesingle-columnstructurecomparedwithordinaryjacketstructureareexplained.Adynamicanalysisofthistypeofstructureismadeandsomeproblemsrelatedtodynamicanalysisaresolved.Inordertocheckthereliabilityofcomputationtheoryandprogramme,modeltestshavebeencarriedout.However,asspaceislimited,theconclusionoftestswillbeintroducedinanotherpaper.Therefore,thistypeofstructureisapplicableforprocticalengineering.

  • 标签: single-column structure DYNAMIC ANALYSIS diffraction wave
  • 简介:Thecoefficientofdeffractionofregularwavesbehindthedoublejettyhasbeencomputedinthispaperatfirstbyusingthesingularitydistributionmethod.Themodeltestsconductedfordiffractionofirregularwaveswithaunidirectionalfrequencyspectrumhaveconfirmedgoodagreementbetweenthedatameasuredinexperimentsandtheresultscomputedbythesingularitydistributionmethodplusthelinearsuperpositionmethodfortheenergyofcomponentwavesinthedirectionalfrequencyspectra.Therefore,thistechniqueforcomponentwavesinthedirectionalspectrahasbeenfurtherusedtocomputediffractionofirregularwavesofmultidirection,includingtheemploymentofadirectionaldistributionfunctionofthecos2type,aswellastheBretschneider-Misuyannfrequencyspectrum.

  • 标签: DIFFRACTION IRREGULAR WAVES DOUBLE jetty OCEAN
  • 简介:Thespudcanfoundationhasbeenwidelyusedinoffshoreengineeringforjack-uprigs.However,'punchthrough'failureoftenoccurswhereastrongersoillayeroverlaysasoftersoillayer.Inthisstudy,spudcanpenetrationintodoublelayeredsoilsisinvestigatednumerically.Thesoilprofileissetupasastrongersoillayeroverlayingasoftersoillayer,withthesoilstrengthratio(bottomsoilstrength/topsoilstrength)variedfrom0.1to1.0(1meansuniformsoil).Thebearingbehaviourisdiscussedandthebearingcapacityfactorsaregivenforvariouscasesinvolvingdifferentlayerthicknessesanddifferentstrengthratiosofthetwoclaylayers.Thedevelopmentoftheplasticzonesandtheeffectofsoilselfweightonthebearingcapacityarealsodiscussed.Fromthisstudy,itisfoundthat,whenaspudcanisdistantfromthesoillayerboundary,thespudcancanbeanalysedwithsinglesoillayerdata.However,whenaspudcanbecomesclosertothesoilboundarylayer,theinfluenceofthelowersoftsoillayerissignificant,andthebearingcapacityofthespudcandecreases.Thecriticaldistanceisanindicationoftheoccurrenceof'punchthrough'failure.Thecriticaldistancebetweenthespudcanandthelayerboundaryislargerforaroughspudcanthantheoneforasmoothone,andthecriticaldistancedecreaseswithincreasingsoilstrengthratio.Thedepthofcavityformedduringinitialspudcanpenetrationdependsonthetoplayersoilstrength,soilstrengthratioandunitsoilself-weight,andthecavityaffectsthespudcanbearingbehaviouraswell.

  • 标签: 深度渗透 双层土壤 海上工程 临界距离 连续分布
  • 简介:从有有势力反的马尾藻类海草tenerrimum(圣)的乙醇摘录的多酚过敏效果被学习通过列层析优化分离过程。三的吸附和解吸附作用特征广泛地使用了吸附物:宏多孔的树脂,硅石胶化,和polyvinylpolypyrrolidone(PVPP),非常分别地被评估并且为多酚的准备分离的优化学习了。这些吸附物上的静态的操作显示出多孔的树脂有的那个宏在三吸附物之中的最好的吸附和解吸附作用能力。有包装的列也是的多孔的树脂进行了优化参数例如的宏的动态吸附和解吸附作用:与在方括号显示出的最佳的价值,摘录答案的集中(4次冲淡了),pH价值(67),吸附速度(3BVh−1,床volumes/per小时),乙醇(80%)的集中,elution速度(3BVh−1)和elution体积(7BV)。那么优化的色析法的过程从粗略的多酚给了62.43%的纯净,提供简历的大规模准备的一个有希望的基础在在测试上面的进一步的可伸缩之上的活跃多酚。

  • 标签: 色谱分离 分离制备 柱色谱 马尾藻 优化 聚乙烯吡咯烷酮
  • 简介:Deep-waterregionsoftenhavewindsfavorableforoffshorewindturbines,andfloatingturbinescurrentlyshowthegreatestpotentialtoexploitsuchwinds.Thisworkestablishedproperscalinglawsformodeltests,whichwerethenimplementedintheconstructionofamodelwindturbinewithoptimallydesignedblades.Theaerodynamic,hydrodynamic,andelasticcharacteristicsoftheproposednewmulti-columntension-leg-typefloatingwindturbine(WindStarTLPsystem)wereexploredinthewavetanktestingofa1:50scalemodelattheStateKeyLaboratoryofOceanEngineeringatShanghaiJiaoTongUniversity.Testswereconductedunderconditionsofstillwater,whitenoisewaves,irregularwaves,andcombinedwind,wave,andcurrentloads.Theresultsestablishedthenaturalperiodsofthemotion,damping,motionresponseamplitudeoperators,andtendontensionsoftheWindStarTLPsystemunderdifferentenvironmentalconditions,andthuscouldserveasareferenceforfurtherresearch.

  • 标签: FLOATING WIND TURBINE model test WindStar
  • 简介:Mobileoffshoredouble-causewaypiersystem,atypeofseashoreunloadingequipment,consistsoftwogroupsofmultipleconnectedsemi-submersiblemodules.Thisstructurehaswideapplicationbecausemostofthemiddleorminitypeofvesselsandshipscanbemooredtoit.Basedontheanalysisofcomputationalmethodsofmulti-bodymotionresponse,ahydrodynamicmodelissetupandthethree-dimensionalpotentialtheoryinfinitedepthisadoptedtocalculatethethree-dimensionalmotionresponseofthissystem.ThedoubleP-Mspectrumisusedtoanalyzethemotionresponseinirregularwaves.Differentwavedirectionsarespeciallytakenintoconsideration,duetotheirvariouseffectstothemotionresponse.Furthermore,thecalculatedresultiscomparedwiththatoftheexperiment,anditisprovedthatsway,heave,pitchandyawmotionaregreatlyconstrainedbymooringsystem.Thecomparisonalsoindicatesthatthemodelcanforecastthemotionperformanceofthetarget,andthatthecalculatedresultcanalsobeusedasreferenceinconnectorandmooringsystemdesign.

  • 标签: 海面移动桥墩系统 多漂浮体 P-M光谱 水力分析
  • 简介:Thespectrumshapecharacteristicsofdouble-peakedseawavespectiaactuallymeasuredintheJiaozhouBaywereanalysedandonerepresentationofdouble-peakedseawavespectrawithsix-parameterswhichcanbedeterminedfromagivenseawavespectrumisproposedinthispaper.Afterverifyingbyfittingprocesswiththedatasetsofdouble-peakedseawavespectrameasuredintheJiaozhouBay,itcanbeseenfromtheresultsthattherepresentationmentionedabovemaybeusedtoexpressthedouble-peakedseawavespectrageneratedintheJiaozhouBayundervariousseastates,andthattheabsolutevaluesofmaximumdeviationindex(D.I.)donotexceed30.0.

  • 标签: fitting ABSOLUTE deviation mentioned ITERATION instead
  • 简介:Thispaperpresentsacoupleddynamicresponseanalysisofamulti-columntension-leg-typefloatingwindturbine(WindStarTLPsystem)undernormaloperationandparkedconditions.Wind-onlyloadcases,wave-onlyloadcasesandcombinedwindandwaveloadcaseswereanalyzedseparatelyfortheWindStarTLPsystemtoidentifythedominantexcitationloads.ComparisonsbetweenanNRELoffshore5-MWbaselinewindturbineinstalledonlandandtheWindStarTLPsystemwereperformed.Statisticsofselectedresponsevariablesinspecifieddesignloadcases(DLCs)wereobtainedandanalyzed.ItisfoundthattheproposedWindStarTLPsystemhassmalldynamicresponsestoenvironmentalloadsanditthushasalmostthesamemeangeneratorpoweroutputunderoperatingconditionsastheland-basedsystem.Thetensionmooringsystemhasasufficientsafetyfactor,andtheminimumtendontensionisalwayspositiveinallselectedDLCs.Theratioofultimateloadofthetowerbasefore-aftbendingmomentfortheWindStarTLPsystemversustheland-basedsystemcanbeashighas1.9inalloftheDLCsconsidered.TheseresultswillhelpelucidatethedynamiccharacteristicsoftheproposedWindStarTLPsystem,identifythedifferenceinloadeffectbetweenitandland-basedsystems,andthusmakerelevantmodificationstotheinitialdesignfortheWindStarTLPsystem.

  • 标签: 动力响应分析 风力发电机组 最小张力 耦合 腿式 风力涡轮机
  • 简介:Almosthalfoftheoceanicwatercolumnsexhibitdouble-diffusion.Theimportanceofdouble-diffusioninglobaloceans'saltandheatfluxes,water-massformationandmixing,andcirculationisincreasinglyrecognized.However,suchanimportantphysicalprocessintheoceanhasnotbeenwellstudied.Oneofthereasonsisthedifficultyofparameterizingandquantifyingtheprocesses.Thepaperpresentedhereattemptstoquantifythedouble-diffusivefluxesofsaltandheatintheocean.Previousqualitativeanalysisbyapplyingthewater-massTurnerangle,mTu,totheNorthPacificIntermediateWater(NPIW)layershowedafavorableconditionforsalt-fingeringintheupperNPIWduetotheoverlyingwarm/saltywaterabovethecold/freshNPIWcore,andadoubly-stableconditioninthelowerNPIWwherepotentialtemperaturedecreaseswithdepthwhilesalinityincreases,inducingdoublestratificationwithrespecttobothpotentialtemperatureandsalinity.Thepresentstudygivesaquantitativeestimateofdouble-diffusivefluxesofsaltandheatcontributedbysalt-fingeringintheupperNPIWlayer.

  • 标签: 北太平洋 介质水流 双扩散 盐分 热量 NPIW
  • 简介:LigninservesasoneofthemostimportantmolecularfossilsfortracingTerrestrialOrganicMatters(TOMs)inmarineenvironment.Extractionandderivatizationofligninoxidationproducts(LOPs)arecrucialforaccuratequantificationoflignininmarinesediment.Herewereportamodificationoftheconventionalalkalinecupricoxide(CuO)oxidationmethod,themodificationconsistinginasolidphaseextraction(SPE)andanovelon-columnderivatizationbeingemployedforbetterefficiencyandreproducibility.Inspikingblanks,recoverieswithSPEfortheLOPsarebetween77.84%and99.57%withrelativestandarddeviations(RSDs)rangingfrom0.57%to8.04%(n=3),whilethosewithtraditionalliquid-liquidextraction(LLE)arefrom44.52%to86.16%withRSDsbeingfrom0.53%to13.14%(n=3).Moreover,thereproducibilityisgreatlyimprovedwithSPE,withlesssolventconsumptionandshorterprocessingtime.Theaverageefficiencyofon-columnderivatizationforLOPsis100.8%±0.68%,whichissignificantlyhigherthanthoseofin-vialorin-syringederivatization,thusresultinginstilllessconsumptionofderivatizingreagents.LignininthesurfacesedimentssampledfromthesouthofYangtzeRiverestuary,China,wasdeterminedwiththeestablishedmethod.Recoveriesof72.66%to85.99%withstandarddeviationlessthan0.01mg/10gdryweightareobtainedexceptforp-hydroxyben-zaldehyde.ThelignincontentΣ8(producedfrom10gdrysediment)intheresearchareaisbetween0.231and0.587mg.S/VandC/Vratios(1.028±0.433and0.192±0.066,respectively)indicatethattheTOMsinthisregionareoriginatedfromamixtureofwoodyandnonwoodyangiospermplants;thehighvaluesof(Ad/Al)vsuggestthattheTOMshasbeenhighlydegraded.

  • 标签: 衍生化气相色谱 木质素含量 海洋沉积物 固相萃取柱 氧化铜 碱性