简介:Theexploitationofdifferentnon-rigorousmathematicalmodelsasopposedtothesatelliterigorousmodelsisdiscussedforgeometriccorrectionsandtopographic/thematicmapsproductionofhigh-resolutionsatelliteimagery(HRSI).Furthermore,thispaperfocusesontheeffectsofthenumberofGCPsandtheterrainelevationdifferencewithintheareacoveredbytheimagesontheobtainedgroundpointsaccuracy.Fromtheresearch,itisobviouslyfoundthatnon-rigorousorientationandtriangulationmodelscanbeusedsuccessfullyinmostcasesfor2Drectificationand3Dgroundpointsdeterminationwithoutacameramodelorthesatelliteephemerisdata.Inaddition,theaccuracyuptothesub-pixellevelinplaneandaboutonepixelinelevationcanbeachievedwithamodestnumberofGCPs.
简介:静态、运动学的testings被使用IGS5min,30年代和5s间隔调查在精确的点放的精确卫星钟产品(PPP)答案。测试结果证明IGS卫星钟的采样率在静态的PPP答案上有很小的效果。精确卫星钟的采样间隔的所有三种类型能满足放精确性的公里厘米水平;更高的采样率没为PPP答案有重要改进。然而,卫星钟的采样率在运动学的PPP在PPP答案上有重要影响。越高卫星钟的间隔,精确性完成了越多更好。运动学的PPP的精确性完成了由用30s间隔,精确卫星钟被使用精确卫星钟和30s间隔卫星钟能几乎生产的5min间隔被将近3050%关于答案改进运动学的答案的一样的精确性。而且,从不同分析中心的精确卫星钟产品的使用可以也差不多在PPP答案上生产效果。
简介:ThispaperfocusesonthestudyofoceanbathymetricinversionfromsatellitealtimeterdatabyusingFFTtechnique.Inthisstudy,thefree-airgravityanomaliesovertheSouthChinaSeaaredeterminedbythesatellitealtimeterdataofGEOSAT,ERS-1,ERS-2andT/P.Andthe2.5′×2.5′bathymetrymodelinSouthChinaSeaiscalculatedfromthegravityanomalieswiththeinversionmodelgiven.Aftertheanalysisoftheinversionandthecomparisonbetweentheresults,someconclusionscanbedrawn.
简介:产生能来自任何很多来源的格子DEM(数字举起模型):例如,到轮廓地图的数字变换的类似物由听模型的申请列在后面,否则经由数字摄影测量学的直接举起点建模适用于在空中的图象或卫星图象。除了从激光雷达数据获得的点云的推广,当前,通常赞成的途径指数字摄影测量学的应用。在如此的推广的最重要的步骤之一是为变化形式点(象素)匹配进程的立体声建立:在建模很困难任何同质的区域由于不同空间特征的缺乏喜欢水盖子或森林canopied区域。作为结果,自动化过程的申请肯定产生错误的举起价值。在这份报纸,我们在场并且为改进经由一个熵质地过滤器的利用产生的立体声DEM的质量使用一个方法。过滤器是在立体声匹配以前,申请了同质的区域的抽取以便一个统计质地过滤器然后能被申请经由一种空间关联技术的推广在插值和精确性评价以前移开异常评估价值。为例证,我们使用了翠菊1B图象的立体声对。
简介:AnimprovedtopographicdatabaseforKingGeorgeIsland,oneofthemostfrequentlyvisitedregionsinAntarctica,ispresented.AfirststepconsistedincombiningdatafromdifferentialGPSsurveysgainedduringtheaustralsummers1997~1998and1999~2000,withthecurrentcoastlinefromaSPOTsatelliteimagemosaic,topographicinformationfromexistingmapsandfromtheAntarcticDigitalDatabase.Fromthisdatasets,adigitalterrainmodel(DTM)wasgeneratedusingArc/InfoGIS.Inasecondstep,asatelliteimagemapatthescale1∶100000wasassembledfromcontourlinesderivedfromtheDTMandthesatellitemosaic.Alackofaccuratetopographicinformationintheeasternpartoftheislandwasidentified.AdditionaltopographicsurveyingorSARinterferometryshouldbeusedtoimprovethedataqualityinthatarea.TheGISintegrateddatabasewillbeindispensableforglaciologicalandclimatologicalstudiesandadministrativeandscientificpurposes.Infuture,theapplicationofGIStechniqueswillbemandatoryforenvironmentalimpactstudiesandenvironmentalmonitoringaswellasformanagementplansonKingGeorgeIsland.
简介:Shorelineextractionisfundamentalandinevitableforseveralstudies.Ascertainingtheprecisespatiallocationoftheshorelineiscrucial.Recently,theneedforusingremotesensingdatatoaccomplishthecomplextaskofautomaticextractionoffeatures,suchasshoreline,hasconsiderablyincreased.Automatedfeatureextractioncandrasticallyminimizethetimeandcostofdataacquisitionanddatabaseupdating.Effectiveandfastapproachesareessentialtomonitorcoastlineretreatandupdateshorelinemaps.Here,wepresentaflexiblemathematicalmorphology-drivenapproachforshorelineextractionalgorithmfromsatelliteimageries.Thesalientfeaturesofthisworkarethepreservationofactualsizeandshapeoftheshorelines,run-timestructuringelementdefinition,semi-automation,fasterprocessing,andsinglebandadaptability.Theproposedapproachistestedwithvarioussensor-drivenimageswithlowtohighresolutions.Accuracyofthedevelopedmethodologyhasbeenassessedwithmanuallypreparedgroundtruthsofthestudyareaandcomparedwithanexistingshorelineclassificationapproach.Theproposedapproachisfoundsuccessfulinshorelineextractionfromthewidevarietyofsatelliteimagesbasedontheresultsdrawnfromvisualandquantitativeassessments.
简介:Anewcomputationalprocedureforderivationofmarinegeoidona2.5′×2.5′gridinanon-tidalsystemovertheSouthChinaSeaandthePhilippineSeafrommulti-satellitealtimeterseasurfaceheightsisdiscussed.Single-anddual-satellitecrossoverswereperformed,andcomponentsofdeflectionsoftheverticalweredeterminedatthecrossoverpositionsusingSand-well'scomputationaltheory,andgriddedontoa2.5′×2.5′resolutiongridbyemployingtheShepard'sinterpolationprocedure.2.5′×2.5′gridofEGM96-derivedcomponentsofdeflectionsoftheverticalandgeoidheightswerethenusedasreferenceglobalgeopotentialmodelquantitiesinaremove-restoreproceduretoimplementtheMolodensky-likeformulavia1D-FFTtechniquetopredictthegeoidheightsovertheSouthChinaSeaandthePhilippineSeafromthegriddedaltimeter-derivedcomponentsofdeflec-tionsofthevertical.Statisticalcomparisonsbetweenthealtimeter-andtheEGM96-derivedgeoidheightsshowedthattherewasaroot-mean-squareagreementof±0.35mbetweentheminaregionoflesstectonicallyactivegeologicalstructures.However,overareasoftectonicallyactivestructuressuchasthePhilippinetrench,differencesofabout-19.9mwereobtained.
简介:植被的上述扎根的生物资源(AGB)估计两个都包括通过一个容量的方程决定的树干生物资源和从地面收集的崽生物资源。为成熟的树,AGB在自从直径,时期被崽生物资源直接在胸高度(DBH)和高度影响的phenologically不同的时间估计在树干生物资源的评价被使用的如此的树的(H)将在一个合理时间时期上仍然保持未改变。在现在的学习,我们在二个形成对照的季节决定了柳安树(Shorearobusta)的AGB:在缺乏与在地面上在场的垃圾的丰富的数量在2月流时期的地面和叶上的垃圾的10月的山峰绿色时期。为2月的AGB的评价包括了崽生物资源。相反,为10月的AGB代表了仅仅树干生物资源。AGB为在学习区域选择的十个不同阴谋被估计。从十采样估计的AGB阴谋因为每次时期是有象一般水准那样的单个树参数的regressed,树的DBH和高度从相应阴谋测量了。回归分析作为与2月相比为10月展出了在AGB和DBH之间的一种显著地更强壮的关系。而且,在遥远地察觉到的导出的数据和AGB之间的关联也被发现比2月为10月显著地更高。这观察显示在AGB的崽生物资源的那包括将趋于减少在遥远地察觉到的数据和AGB之间的在AGB和DBH之间并且也的回归关系。因此,当在phenologically不同的时间时期从卫星数据估计AGB时,这些结论邀请小心的考虑。