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简介：Thispaperpresentsadatafusionmethodindistributedmulti-sensorsystemincludingGPSandINSsensors'dataprocessing.First,aresidualχ2-teststrategywiththecorrespondingalgorithmisdesigned.Thenacoefficientmatricescalculationmethodoftheinformationsharingprincipleisderived.Finally,thefederatedKalmanfilterisusedtocombinetheseindependent,parallel,real-timedata.Apseudolite(PL)simulationexampleisgiven.

简介：Owingtothelongpropagationdelayandhigherrorrateofacousticchannels,itisverychallengingtoprovidereliabledatatransferforunderwatersensornetworks.Moreover,networkcodingisprovedtobeaneffectivecodingtechniqueforthroughputandrobustnessofnetworks.Inthispaper,weproposeaReliableBraidedMultipathRoutingwithNetworkCodingforunderwatersensornetworks(RBMR-NC).Disjointmulti-pathalgorithmisusedtobuildindependentactualpaths,ascalledmainpaths.Somebraidedpathsoneachmainpatharebuiltaccordingtothebraidedmulti-pathalgorithm,whicharecalledlogicpaths.Whenadatapacketistransmittedbythesenodes,thenodescanemploynetworkcodingtoencodepacketscomingfromthesamegroupinordertofurtherreducerelativityamongthesepackets,andenhancetheprobabilityofsuccessfuldecodingatthesinknode.Braidedmulti-pathcanmakethemainpathstobemultiplexedtoreducetheprobabilityoflongpaths.ThispapermainlyemployssuccessfuldeliveryratetoevaluateRBMR-NCmodelwiththeoreticalanalysisandsimulationmethods.TheresultsindicatethattheproposedRBMR-NCprotocolisvaluabletoenhancenetworkreliabilityandtoreducesystemredundancy.

简介：回响在浅水里是重要的并且在OBC系列生产明显的槽口。它也降级节和增加的质量处理和解释的困难。这篇文章介绍在槽口之间的关系，射击基于地震卷绕旋转模型的深度，和海床深度。前面的建模基于波浪方程理论被用来验证这种关系。双传感器的求和被使用压制接收装置方面multiples并且基于OBC技术的详细分析根据对下面去的波浪地的地震检波器和水中听音器的相反的反应移开槽口。在实际应用获得的好结果揭示这个方法的有效性。

简介：Duetothelargescaleandcomplexityofcivilinfrastructures,structuralhealthmonitoringtypicallyrequiresasubstantialnumberofsensors,whichconsequentlygeneratehugevolumesofsensordata.Innovativesensordatacompressiontechniquesarehighlydesiredtofacilitateefficientdatastorageandremoteretrievalofsensordata.ThispaperpresentsavibrationsensordatacompressionalgorithmbasedontheDifferentialPulseCodeModulation(DPCM)methodandtheconsiderationofeffectsofsignaldistortionduetolossydatacompressiononstructuralsystemidentification.TheDPCMsystemconcernedconsistsoftwoprimarycomponents:linearpredictorandquantizer.FortheDPCMsystemconsideredinthisstudy,theLeastSquaremethodisusedtoderivethelinearpredictorcoefficientsandJayantquantizerisusedforscalarquantization.A5-DOFmodelstructureisusedastheprototypestructureinnumericalstudy.NumericalsimulationwascarriedouttostudytheperformanceoftheproposedDPCM-baseddatacompressionalgorithmaswellasitseffectontheaccuracyofstructuralidentificationincludingmodalparametersandsecondorderstructuralparameterssuchasstiffnessanddampingcoefficients.ItisfoundthattheDPCM-basedsensordatacompressionmethodiscapableofreducingtherawsensordatasizetoasignificantextentwhilehavingaminoreffectonthemodalparametersaswellassecondorderstructuralparametersidentifiedfromreconstructedsensordata.

简介：Atpresent,mostunderwaterpositioningalgorithmsimprovethepositioningaccuracybyincreasingthenumberofanchornodeswhichresultingintheincreasingenergyconsumption.Tosolvethisproblem,thepaperproposesalocalizationalgorithmassistedbymobileanchornodeandbasedonregiondetermination(LMRD),whichnotonlyimprovesthepositioningaccuracyofnodespositioningbutalsoreducestheenergyconsumption.Thisalgorithmisdividedintotwostages:regiondeterminationstageandlocationpositioningstage.Intheregiondeterminationstage,thetargetregionisdividedintoseveralsub-regionsbytheregiondivisionstrategywiththesmallestoverlapratewhichcanreducethenumberofvirtualanchornodesandlockthetargetnodetoasub-region,andthenthroughtheplanningofmobilenodestooptimizethetravelpath,reducethemovingdistance,andreducesystemenergyconsumption.Inthelocationpositioningstage,thetargetnodelocationcanbecalculatedusingtheHILBERTpathplanningandtrilateration.Thesimulationresultsshowthattheproposedalgorithmcanimprovethepositioningaccuracywhentheenergyconsumptionisreduced.

简介：ThestatisticalcharacterofQuikSCATscatterometerwindsisshowed.AndMonthlychangeandspecialdistributioncharacterofstrongwindfrequencyandmonthlywindfieldsinSouthChinaSeaisanalyzed.ItisshownintheresultthattheQuikSCATscatterometerwindscanberelieduponfortheSouthChinaSea;twowinds,onethewintertimenortheasterlyandtheothersummertimesouthwesterly.ThenortheasterlycentersattheBashiStraitandTaiwamStraitanditssecondarycenterandthemaximumcenterofthesouthwesterlyareinthecentralandsouthernSouthChinaSea.