简介：Three-dimensionelectronicchartdisplayinformationsystem(ECDIS)isoneofthenewdevelopingdirectionsofelectronicnavigationchart,anditsreal-timequalityisoneoftheimportantrequirements.Inthispaperthealgorithmofsimplifyingtrianglesurfaceusingedgecontraction,whichcanensurethereal-timedisplayofobjectsinseabedenvironment,wasputforward.TheoptimumcontractionpointwasdeterminedbytheLagrangematrix,sothatthealgorithmensuresthatthecontractionpointlocatesontheoriginalmodel,meanwhilemeetsthedemandsofleastdeviation.Thisalgorithmcanimprovetheplottingspeed,andpreservetheboundarycharacterbyusingthefewertrianglestosimulateobjects.

简介：Thispaperdescribespathre-planningtechniquesandunderwaterobstacleavoidanceforunmannedsurfacevehicle（USV）basedonmulti-beamforwardlookingsonar（FLS）.Near-optimalpathsinstaticanddynamicenvironmentswithunderwaterobstaclesarecomputedusinganumericalsolutionprocedurebasedonanAalgorithm.TheUSVismodeledwithacircularshapein2degreesoffreedom（surgeandyaw）.Inthispaper,two-dimensional（2-D）underwaterobstacleavoidanceandtherobustreal-timepathre-planningtechniqueforactualUSVusingmulti-beamFLSaredeveloped.Ourreal-timepathre-planningalgorithmhasbeentestedtoregeneratetheoptimalpathforseveralupdatedframesinthefieldofviewofthesonarwithaproperupdatefrequencyoftheFLS.Theperformanceoftheproposedmethodwasverifiedthroughsimulations,andseaexperiments.Forsimulations,theUSVmodelcanavoidbothasinglestationaryobstacle,multiplestationaryobstaclesandmovingobstacleswiththenear-optimaltrajectorythatareperformedbothinthevehicleandtheworldreferenceframe.Forseaexperiments,theproposedmethodforanunderwaterobstacleavoidancesystemisimplementedwithaUSVtestplatform.TheactualUSVisautomaticallycontrolledandsucceededinitsreal-timeavoidanceagainstthestationaryunderseaobstacleinthefieldofviewoftheFLStogetherwiththeGlobalPositioningSystem（GPS）oftheUSV.

简介：在飞机坠毁，轮船碰撞，和另外的事故以后产生的负担可以破坏很大的漂浮的结构(VLFS)并且创造另外的接头负担。在这研究，负担被考虑建立的轮船碰撞和波浪的联合效果打手势为多身体VLFS的微分方程。一个时间领域计算方法被建议在波浪计算VLFS的接头负担。LonguetHiggins模特儿被雇用模仿随机的波浪负担。液体力量和水动力学系数用DNVSesam软件被获得。运动当频率域水动力学系数被变换成运动的存储器函数时，微分方程被使用时间域方法计算时间域的微分方程。由于波浪和影响负担的联合行动，高周波的摆动在接头负担的时间历史曲线被观察。在0的波浪方向？

简介：Directtime-domainsimulationoffloatingstructureshasadvantages:itcancalculatewavepressurefieldsandforcesdirectly;anditisusefulforcoupledanalysisoffloatingstructureswithamooringsystem.Atime-domainboundaryintegralequationmethodispresentedtosimulatethree-dimensionalwaterwaveradiationproblems.Astableformoftheintegrationfree-surfaceboundarycondition(IFBC)isusedtoupdatevelocitypotentialsonthefreesurface.Amulti-transmittingformula(MTF)methodwithanartificialspeedisintroducedtotheartificialradiationboundary(ARB).Themethodwasappliedtosimulateasemi-sphericalliquefiednaturalgas(LNG)carrierandasemi-submersibleundergoingspecifiedharmonicmotion.NumericalparameterssuchastheformoftheARB,andthetimeandspacediscretizationrelatedtothismethodarediscussed.Itwasfoundthatagoodagreementcanbeobtainedwhenartificialspeedisbetween0.6and1.6timesthephasevelocityofwaterwavesintheMTFmethod.Asimulationcanbedoneforalongperiodoftimebythismethodwithoutproblemsofinstability,andthemethodisalsoaccurateandcomputationallyefficient.

简介：Nonlinearwaveloadscaninducelow-frequencyandhigh-frequencyresonancemotionsofamooredplatformindeepwater.Fortheanalysisofthenonlinearresponseofanoffshoreplatformundertheactionofirregularwaves,themostwidelyusedmethodinpracticeistheCumminsmethod,inwhichthesecond-orderexcitingforcesinthetimedomainarecomputedbyatwo-termVolterraseriesmodelbasedonincidentwaves,first-orderbodymotionresponse,andquadratictransferfunctions(QTFs).QTFsarebichromaticwavesactingonabodyandarecomputedinthefrequencydomaininadvance.Formovingbodies,QTFsarerelatedtothefirst-orderbodyresponse,whichistobedeterminedinthesimulationprocessofbodymotionresponsebutisunknowninthecomputationprocedureofQTFs.Insolvingthisproblem,TengandCong(2017)proposedamethodtodividetheQTFsintodifferentcomponents,whichareunrelatedtothebodyresponse.WiththeapplicationofthenewQTFcomponents,amodifiedCumminsmethodcanbedevelopedforthesimulationofthenonlinearresponseofamooredfloatingplatform.Thispaperpresentsareviewofthetheory.

简介：这篇论文集中于与一个帮助DP的绳索系统装备的一个半能沉入水中的平台的研究。基于帮助DP的绳索系统的工作原则和平台运动的模型，一个时间域模拟程序被使用分析影响在一线失败的情况中，在平台运动上，驱动推进器和系在的线的紧张的消费。结果显示出那，在10年的风下面主导，一线失败几乎没在系在的线的紧张上有很少影响。当失败线是上风的时，电源消费将与精确性的一个削弱的位置极大地增加。然而失败线是什么时候下风，电源消费将与精确性的一个部分加强的位置被减少。

简介：Itisverydifficulttoestimateexactvaluesoftimeandcostofanactivityinprojectschedulingprocessbecausemanyuncertainfactors,suchasweather,productivitylevel,humanfactorsetc.,dynamicallyaffectthemduringprojectimplementationprocess.AGAs-basedfullyfuzzyoptimaltime-costtrade-offmodelispresentedbasedonfuzzysetsandgeneticalgorithms(GAs).Intihsmodelallparametersandvariablesarecharacteristicsbyfuzzynumbers.AndthenGAsisadoptedtosearchfortheoptimalsolutiontothismodel.Themethodsolvesthetime-costtrade-offproblemsunderanuncertainenvironmentandisprovedpracticablethroughagivingexampleinshipbuildingscheduling.

简介：把低频率的充满水的阻抗试管测试设备基于存在，它是在北京的海军的海底的战争中心的低频率设备的部分，一个改进充满水的脉搏试管方法在这份短报纸被介绍。因为能力，这建议研究与常规脉搏试管方法显著地不同因为一架单个飞机抑制了正弦脉搏向招手与常规波形和大约1ms的短持续时间时间在充满水的脉搏试管产生。在脉搏的产生过程期间，一个反的过滤器原则被采用补偿变换器反应。试管结束的特征的效果能通过脉搏的产生过程被消除。从一个水/空气接口的思考系数被测量验证建议方法。什么时候与期望的理论价值相比，一个相对好的协议能在5002000Hz的低频率范围被获得。

简介：ADRNN(diagonalrecurrentneuralnetwork)anditsRPE(recurrentpredictionerror)learningalgorithmareproposedinthispaper.UsingofthesimplestructureofDRNNcanreducethecapacityofcalculation.TheprincipleofRPElearningalgorithmistoadjustweightsalongthedirectionofGauss-Newton.Meanwhile,itisunnecessarytocalculatethesecondlocalderivativeandtheinversematrixes,whoseunbiasednessisproved.Withapplicationtotheextremelyshorttimepredictionoflargeshippitch,satisfactoryresultsareobtained.Predictioneffectofthisalgorithmiscomparedwiththatofauto-regressionandperiodicaldiagrammethod,andcomparisonresultsshowthattheproposedalgorithmisfeasible.

简介：僵硬声学的散布由的部件的分离在水下目标在获得如此的目标的结构的特征是必要的。克服看起来有一样的僵硬结构的问题光谱在时间领域的结构，时间频率窗帘来源分离(BSS)能与图象形态学在联合被使用分开不同目标的僵硬散布部件。基于一个热点模型，有时间频率分发的目标的僵硬散布结构的分离被推出。用一个词法过滤器，在Wigner-Ville分布(WVD)的不同特征观察到术语能被简化移开任何跨术语的干扰单个汽车术语和十字。由选择术语表明的汽车的时间和频率点，BSS的精确性能被改进。试验性的模拟被使用了，与在播送信号，相对振幅和时间延期参数的脉搏宽度的变化，以便分析这个新方法的可行性。模拟结果证明新方法不仅能分开僵硬散布当有弹性的散布并且僵硬散布时，部件，而且罐头也分开部件同时存在。试验性的结果证实新方法能在分开僵硬散布结构被使用在水下目标。