简介：Ｃｒｕｓｔａｌｓｔｒｕｃｔｕｒｅａｎｄａｃｃｕｒａｔｅｈｙｐｏｃｅｎｔｅｒｄｅ┐ｔｅｒｍｉｎａｔｉｏｎａｌｏｎｇｔｈｅＬｏｎｇｍｅｎｓｈａｎｆａｕｌｔｚｏｎｅＺＨＵＺＨＡＯ１）（赵珠）ＪＵＮＦＡＮ１）（范军）ＳＩ－ＨＵＡＺＨＥＮＧ２）（郑斯华）ＡＫ...

简介：ICSED(ImprovedClusterShadeEdgeDetection)algorithmandothervariousmethodstoaccuratelyandefficientlydetectedgesonsatellitedataarepresented.ErrorratecriterionisusedtostatisticallyevaluatetheperformancesofthesemethodsindetectingoceanicfeaturesforbothnoisefreeandnoisecontaminatedAVHRR(AdvancedVeryHighResolutionRadiometer)IRimagewithKuroshio.Also,practicalexperimentsindetectingtheeddyofKuroshiowiththesemethodsarecarriedoutforcomparison.ResultsshowthattheICSEDalgorithmhasmoreadvantagesthanothermethodsindetectingmesoscalefeaturesofocean.Finally,theeffectivenessofwindowsizeofICSEDmethodtooceanicfeaturesdetectionisquantitativelydiscussed.

简介：Anovelhybridapproachforearthquakelocationisproposedwhichusesacombinedcoarseglobalsearchandfinelocalinversionwithaminimumsearchroutine,plusanexaminationoftherootmeansquares(RMS)errordistribution.ThemethodexploitstheadvantagesofnetworkraytracingandrobustformulationoftheFréchetderivativestosimultaneouslyupdateallpossibleinitialsourceparametersaroundmostlocalminima(includingtheglobalminimum)inthesolutionspace,andfinallytodeterminethelikelyglobalsolution.Severalsyntheticexamplesinvolvinga3-Dcomplexvelocitymodelandachallengingsource-receiverlayoutareusedtodemonstratethecapabilityofthenewly-developedmethod.Thisnewglobal-localhybridsolutiontechniquenotonlyincorporatesthesignificantbenefitsofourrecentlypublishedhypocenterdeterminationprocedureformultipleearthquakeparameters,butalsoofferstheattractivefeaturesofglobaloptimalsearchingintheRMStraveltimeerrordistribution.Unlikethetraditionalglobalsearchmethod,forexample,theMonteCarloapproach,wheremillionsoftestshavetobedonetofindthefinalglobalsolution,thenewmethodonlyconductsamatrixinversiontypelocalsearchbutdoesitmultipletimessimultaneouslythroughoutthemodelvolumetoseekaglobalsolution.ThesearchisaidedbyinspectionoftheRMSerrordistribution.Benchmarktestsagainsttwopopularapproaches,thedirectgridsearchmethodandtheoct-treeimportantsamplingmethod,indicatethatthehybridglobal-localinversionyieldscomparablelocationaccuracyandisnotsensitivetomodestlevelofnoisedata,butmoreimportantlyitofferstwo-orderofmagnitudespeed-upincomputationaleffort.Suchanimprovement,combinedwithhighaccuracy,makeitapromisinghypocenterdeterminationschemeinearthquakeearlywarning,tsunamiearlywarning,rapidhazardassessmentandemergencyresponseafterstrongearthquakeoccurrence.