简介:Theestuaryandcoastisanareawherethelandandtheseainteractandaplaceinwhichhumanbeingsfrequentlymoveaboutsothatunderstandingandcontrollingthechangeanddevelopmentmodesofthecoastallandformplaysavitalpartinexploitingandprotectingcoastalresources.Amodelisthegeneralizationandabstractionofobjectivethings.Thispapersummarizesfourmethodsforthelandformdevelopmentofthetidalshoreandunderwaterdelta,mainlydiscussesthemodel'sstructuralelements,andpresentstheirspecificapplicationonthebasisoftheauthors'casestudy.Withtheapplicationoftheprofilemodel,thedynamicchangeofcoastallandformcanbeclearlyseenbycontrastingthedifferentprofilesofdifferentyears.Throughtheshrinking,expandingandtransformationoftheisobath,planemodelisusedtostudythemacro-changeoftheshoalandthecoastallandform.Speedmodelisanefficientmeanstoanalyzethetrendoferosionanddepositionandthelocalchangeinagreatareaofthesea.Statisticalsurveymodelisastaticanalysis,whichcanbeusedtoestablishtherelationshipbetweentheerosionanddepositionoftheshoalandthealtitudeandslopeofsurveyspot.
简介:ExplosionforthetreatmentofunderwatersoftfoundationisatechniquenewlydevelopedinChina.ThispaperdescribestheapplicationofthemethodofexplosiontounderwatersoftfoundationtreatmentoftheGreat-WestDyke,LianyungangPort,includingthetechnicalcharacteristicsandtheeffect,selectionofexplosionparameters,workmanshipofconstruction,requirementsofqualityandinspection,andthelike.
简介:NeomysisawatschensiswascollectedonthewestcoastofJiaozhouBay,Qingdaoin1992andacclimatedinthelaboratoryconditions.Theacutetoxicitymethodusing4~6dayjuvenilemysidofthisspeciesisstudied.ThespeciesiscomparedwithM.bahiaintaxonomy,geographicdistribution,morphology,aswellasthesensitivitytoAbstracttoxins.Basedontheresults,werecommendN.awatschensistobeastandardmarineorganismfortoxicitytestinChinaandthemethodtobeappliedintoxicityevaluationofdrillingfluids.Inthispaper,wereporttheresultsoftheabovestudiesandtheapplicationofthemethodintheevaluationofseveraldrillingfluidproducts.
简介:Metalpollutioninaquaticecosystemsisofimmenseimportance.Undervariousenvironmentcircumstances,themetalcontentsofsedimentscanenterintotheoverlyingwaterbodyleadingtoseveretoxicity.ThisstudyaimstodeterminemetalconcentrationsinsedimentsofAnzaliInternationalWetlandinIran.Chemicalpartitioningmethodisusedtodeterminetheportionofanthropogenicpollutionandthemobilitypotentialofeachmetal.Theintensityofmetalpollutioninsedimentsofthewetlandisassessedusingthreereliableindices.TheresultsofchemicalpartitioningrevealthatcadmiumbearthehighestriskofbeingreleasedintotheaquaticenvironmentandhighamountofmanganeseinsulfidebondphaseimpliestheinitiationofredoxstateinaquaticenvironmentoftheAnzaliWetland.TheresultsofchemicalpartitioningstudiesshowthatPb,Cd,MnandAshavethehighestanthropogenicportion.Clusteranalysisalsoconfirmstheresultsofchemicalpartitioningandindicatesthatthementionedmetalscanbeoriginatedfromanthropogenicsources.Sedimentpollutionindices,including,I_geo,I_POLL,andm-ERM-Qrevealthatmetalsareintherangeoflowtomoderatepollutionandalsoshowthatthehighestmetalpollutionisintheeasternandcentralpartsofthewetland.Thiscanbeascribedtoriverswhicharetherecipientofindustrial,agriculturalandmunicipalwastewatersandflowintothesepartsofthewetland.
简介:OwingtotheBenjamin-Feirinstability,theStokeswavetrainexperiencesamodulation-demodulationprocess,andpresentsarecurrencecharacteristics.StiassnieandShemerresearchedtheunstableevolutionprocessandprovidedatheoreticalformulationfortherecurrenceperiodin1985onthebasisofthenonlinearcubicSchrdingerequation(NLS).However,NLShaslimitationsonthenarrowbandandtheweaknonlinearity.Therecurrenceperiodisre-investigatedinthispaperbyusingahighlyefficientHighOrderSpectral(HOS)method,whichcanbeappliedforthedirectphaseresolvedsimulationofthenonlinearwavetrainevolution.ItisfoundthattheStiassnieandShemer’sformulashouldbemodifiedinthecaseswithmostunstableinitialconditions,whichisimportantforsuchtopicsasthegenerationmechanismsoffreakwaves.AnewrecurrenceperiodformulaispresentedandsomenewevolutioncharacteristicsoftheStokeswavetrainarealsodiscussedindetails.
简介:AnewanalyticalmethodusingBack-Propagation(BP)artificialneuralnetworkandkineticspectrophotometryforsimultaneousdeterminationofironandmagnesiumintapwater,theYellowRiverwaterandseawaterisestablished.Byconditionalexperiments,theoptimumanalyticalconditionsandparametersareobtained.Levenberg-Marquart(L-M)algorithmisusedforcalculationinBPneuralnetwork.Thetopologicalstructureofthree-layerBPANNnetworkarchitectureischosenas15-16-2(nodes).Theinitialvalueofgradientcoefficientμisfixedat0.001andtheincreasefactorandreductionfactorofμtakethedefaultvaluesofthesystem.ThedataareprocessedbycomputerswithourownprogramswritteninMATLAB7.0.Therelativestandarddeviationofthecalculatedresultsforironandmanganeseis2.30%and2.67%respectively.Theresultsofstandardadditionmethodshowthatforthetapwater,therecoveriesofironandmanganeseareintherangesof98.0%-104.3%and96.5%-104.5%,andtheRSDisintherangeof0.23%-0.98%;fortheYellowRiverwater(LijindistrictofShandongProvince),therecoveriesofironandmanganeseareintherangesof96.0%-101.0%and98.7%-104.2%,andtheRSDisintherangeof0.13%-2.52%;fortheseawaterinQingdaooffshore,therecoveriesofironandmanganeseareintherangesof95.3%-104.8%and95.3%-104.7%,andtheRSDisintherangeof0.14%-2.66%.Itisfoundthat21commoncationsandanionsdonotinterferewiththedeterminationofironandmanganeseundertheoptimumexperimentalconditions.Thismethodexhibitsgoodreproducibilityandhighaccuracyinthedeterminationofironandmanganeseandcanbeusedforthesimultaneousdeterminationofironandmanganeseintapwaterandnaturalwater.ByusingtheestablishedANN-catalyticspectrophotometricmethod,theironandmanganeseconcentrationsofthesurfaceseawaterat11sitesinQingdaooffshorearedeterminedandtheleveldistributionmapsofironandmanganesearedrawn.
简介:Full-rangenonlinearanalysisoffatiguebehaviorsofreinforcedconcretestructuresbyfiniteelementmethod¥SongYupu;ZhaoShunbo;WangRuim...
简介:Themovingparticlesemi-implicit(MPS)methodhasdemonstrateditsusefulnessinpracticalengineeringapplications.Althoughithaswideapplicability,itisstillhardtopredictthepressurepreciselyusingtheMPSmethod.Apressure-convectionparticlemethodbasedontheMPSmethodisproposedtoovercomethisproblem.Theimprovedperformanceofthisnewmethodisvalidatedwithcomputationalandmeasuredresults.Theapproachisalsoappliedtocomputetheproblemofsloshingassociatedwithfloatingbodymotioninwaves.Thepressure-convectionMPSmethoddemonstrateditscapabilitytoimprovethepredictionofpressure.
简介:Ninesamplesofsuspendedmatteratthesurfaceorbottomand34elementsin20samplesofsubstratesedimenthavebeenusedintheneutronactivationanalyses.Authorsstudysedimentandsuspendedmattermovementbyusingthemethodofelementgeochemistry,andconcludethroughsyntheticanalysisandprocessingthatthemovementdirectionofsuspendedmatterandsubstratesedimenttendstoconvergeonthecentralarea.
简介:基于相关矩阵特征向量的目标分解将地物回波复杂的散射过程分解成相互独立的三种单一散射分量:单向散射、双向散射和交叉散射,分别对应各自的目标相关矩阵.目标分解技术降低了散射回波之间的相关性,有利于分析地物散射机理,有助于提高分类精度.对荷兰Flevoland地区全极化数据进行分解,经过试验和相关性分析,选用7种数据形成多参数数据组合,对其进行最大似然监督分类,同时进行常规三种极化加相位差的分类和基于复Wishart分布的最大似然分类,逐像元计算混淆矩阵,分析对比三种分类结果的精度,试验表明:相对于常规数据组合分类,基于复Wishart分布的监督分类可以小幅度提高分类精度,而利用目标分解得到多参数组合数据进行分类则有大幅度的提高。
简介:AnovelmodelingtechniquebasedonthecoupledEulerian-Lagrangian(CEL)methodisprovidedtosolvethegeotechnicalproblemswithlargedeformations.Thetechniqueisintendedtosolvetheupdateproblemofsoilmechanicalpropertiesduringspudcanpenetrationinnormallyconsolidatedclaysoil.IntheCELmodel,thenormalmethodofassigninganincreasingshearstrengthprofilewithdepth(NA)isdefectiveduetoitsEulerianframework.Inthispaper,anewtechniqueisproposedtoupdatesoilmaterialpropertiesbyintroducingthermo-mechanicalcoupledanalysis(TMCA)totheCELmodels.DuringestablishmentoftheCELmodels,theoptimalpenetrationvelocityandminimummeshsizearedeterminedthroughparametricstudies.Reasonabilityandaccuracyarethenverifiedthroughcomparisonofthepreliminaryresultswiththesoilflowconfigurationandpenetrationresistance(Fv)ofacentrifugetest,andtheresultsoftheproposedmethodarecomparedwiththoseoftheremeshingandinterpolationtechniquewithsmallstrain(RITSS)method.ToachieveaCELmodelwithsatisfactoryaccuracy,theNAandTMCAmethodsimplementedintheCELmodelsandtheRITSSmethodarefirstadoptedinweightlesssoil.ComparisonofthefindingswiththoseobtainedinpreviousstudiesshowsthattheTMCAmethodcanupdatematerialpropertiesandpredictFv.TheTMCAmethodisthenappliedtosoilswithself-weightanddifferentshearstrengthprofiles.Resultsshowthattheproposedmethodiscapableofaccuratelymodelingthelargedeformationproblemofspudcanpenetrationinnon-homogeneousclay.
简介:浮标系统的推广是为浮标系统的操作的最重要的过程之一。在现在的学习,包含表面浮标的一个单个点的绳索浮标系统,有部件的电报片断,锚被使用多身体动力学等等建模方法。运动方程在分离节点描述和充分笛卡儿的坐标被开发。然后数字的方法被用来解决平常的微分方程,当锚从董事会正在扔时,动力学模拟被完成。没有电流并且与在浮标系统的电流的不同节点的轨道和速度被获得。电缆线的每部分的短暂紧张力量在推广的进程被分析。当锚正在摸海床和力量将与不同漂浮配置改变的最大的紧张时,数字结果显示短暂收费载重增加到山峰价值。这个工作对浮标系统计划的设计和推广有用。
简介:Animpedanceanalyticalmethod(IAM)isdevelopedtostudytheinteractionofplanewaterwavewithaslotted-wallcaissonbreakwater.Thenon-linearboundaryconditionattheslotted-wallisexpressedintermsofflowresistance.Asetofalgebraicexpressionsareobtainedforfreesurfaceelevationinsideandoutsidechamber,andreflectioncoefficient.Thepredictionofthereflectioncoefficientsshowsthattherelativewidthsofthechamberinducingtheminimumreflectioncoefficientforaslotted-wallcaissonbreakwaterareinarangeof0.10~0.20,whicharesmallerthanthat(0.15~0.25)foraperforated-wallcaissonbreakwater.Thereflectioncoefficientsandfreesurfaceelevationobtainedbythepresentmodelarecomparedwiththatoflaboratoryexperimentscarriedoutbypreviousresearchers.