简介:Thispaperfirstdevelopstheapproachestodeterminethegeopotentialofthelocalmeansealevel,andtheninvestigatestheoffsetofthe1985verticaldatumsurfacedefinedbythemeansealevelofYellowSeaattheDagangTideGaugeinQingdaocityusingthedevelopedapproachesandGPS/levelingdata.Itshowsthatthegeopotentialofthelocalmeansealevelatthetidegaugeisequalto62636853.5±0.2m2*s-2andthatthe1985verticaldatumsurfaceis24.6±5.4cmabovethegeoidrealizedbythegeopotentialW0=62636856.0±0.5m2*s-2.
简介:Thesimilaritytransformationmodelbetweendifferentcoordinatesystemsisnotaccurateenoughtodescribethediscrepancyofthem.Therefore,thecoordinatetransformationfromthecoordinateframewithpooraccuracytothatwithhighaccuracycannotguaranteeahighprecisionoftransformation.Inthispaper,acombinedmethodofsimilaritytransformationandregressiveapproximatingispresented.Thelocalerroraccumulationanddistortionaretakenintoconsiderationandtheprecisionofcoordinatesystemisimprovedbyusingtherecommendedmethod.
简介:Undertheframeworkofsupportvectormachines,thispaperproposesanewkernelmethodbasedonneighborbandsmutualinformationforhyperspectraldatumclassification.Thisalgorithmassignsweightstodifferentbandsinthekernelfunctionaccordingtotheamountofusefulinformationthattheycontain,whichmakesthebandwithmoreusefulinforma-tionplaymoreimportantroleintheclassification.Ourresearchhasshownthatthebandwithgreatermutualinformationbetweenneighborbandscontainsmoreusefulinformation,andhenceweusethemutualinformationofeachbandanditsneighborbandsastheweightsoftheproposedkernelmethod.Theexperimentalresultsshowthatforthesupportvectormachinesbasedonpolynomialandradialbasisfunction,afterintroducingtheproposedkernelfunction,theaverageaccuracyisincreasedmorethan1.2%withoutusinganyreferencemaporincreasingmuchmorecomputationaltime.