简介:ThemainpurposetodevelopaMapGraphicWorkstationonthewidelyusedmicro-computeristhatbyitthewholeprocessingofmapdatafromcapturing,managing,editing,updatingtographicoutputtingcanberealized.MapDigitizationSystem(MDS)isthesoftwaresystemtodealwiththeinitialandalsothemostimportantprocessing.Inthispaper,theauthorsintroduceaMDSonamicro-computerbasedMapGrphicWorkstationthathasbeenqualitifiedfortheproducationofdigitalmap.SincethesystemisdesignedtotallyindependentlyandinthegeneralframeoftheMapGraphicWorkstation,thecapturingandman-agingandotherprocessingsformapdataareinanintegralmanner,inwhichtheproducationofdigitalmapcanbefulfilledconveniently.Atthesametime,thesystemisflexibleforfunctionextensionandwidelyapplicabletothedatafromdif-ferentsourcesandwithdifferentinformationcharacterisitcs(e.g.,theprocessingofChinesecharactersonmap).
简介:Ahybridthinningalgorithmforbinarytopographymapsisproposedonthebasisofparallelthinningtemplatesinthispaper.Thealgorithmhasahighprocessingspeedandthestrongabilityofnoiseimmunityandpreservationofconnectivityandskeletonsymmetry.Experimentalresultsshowthatthealgorithmcansolvethethinningproblemofbinarymapseffectively.
简介:排水量操作员是一重要、静止在地图归纳的一个热话题。在归纳产品,符号一定不含糊、容易察觉、容易地听说,它在特征之中做空格竞争在地图的进程的一个重要障碍反对排水量。通过繁殖过程,在目标之间的空间冲突可以被散布,更多的目标可以漂流进它。为了维持符号,在符号的对象,一些不重要的符号或部分之间的平衡和空间关系应该根据视觉图形的分辨率阀值在限制下面被弄歪在地图特征之中弄明白空格竞争。包括位置,易读性和特征的三限制为符号平衡和空间关系的维护是重要的,它在这篇论文被讨论。骨骼被介绍表示区域目标考虑特征,一个区域目标能在被分开到在构造根据他们的重要性分开教主的联盟者。然后,有限元素方法被用于地图目标的排水量和失真,为有限元素方法的参数的策略在被讨论。
简介:Thegenerationofhigh-resolutionDEMfrominterferometricSARhasresultedintheneedforaccurateandefficientmethodsof2-dimensionalphaseunwrapping.Inthispaper,wegiveabriefdescriptionofthemathematicalbaseofphaseunwrapping,andadetaileddescriptionoftheunweightedandweightedleastsquarephaseunwrappingalgorithm.Thenouralgorithmcombiningwiththeweightedleastsquarephaseunwrappingguidedbythebranch-cutsderivedfromGoldstein’salgorithmandcoherencecoefficientmapderivedfromtheINSARdataisprovided.InourexperimentwewritesubroutinesoftheGoldstein’sbranch-cutalgorithm,unweightedandweightedleastsquarephaseunwrappingalgorithmaswellasouralgorithm,andconstructasmallexperimentsystemtoresolvethephaseunwrappingproblem.FinallywetestouralgorithmonsomeINSARdata.Theresultshowsthatourapproachcanobtainunwrappedphasecorrectlyandefficiently.
简介:Thispapermakesastudyontheinteractivedigitalgener-alization,wheremapgeneralizationcanbedividedintointellectivereason-ingprocedureandoperationalproce-dure,whicharedonebyhumanandcomputer,respectively.Andaninter-activemapgeneralizationenvironmentforlargescaletopographicmapisthendesignedandrealized.Thisresearchfocuseson:①thesignificanceofre-searchinganinteractivemapgenerali-zationenvironment,②thefeaturesoflargescaletopographicmapandinter-activemapgeneralization,③thecon-structionofmapgeneralization-orien-teddatabaseplatform.
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:ThispaperdiscussestheplacementofChineseannotationfrompointofviewofgraphics.AreaFeatureisclassifiedassimplepolygon,complexpolygonandspecialpolygon.Forsimpleones,annotationsareplacedalongthelongestedge.Forcomplexones,firstlythepolygonaresimplifiedaccordingtoclosepoints,thenthelongestdiagonalisgottenbycomparinglength,lastly,annotationsareplacedalonglong-diagonal.Forspecialones,thepolygonarepartitionedintoseveralpartsbyacertainruleforgettingtheirsub-diagonals,thentheirannotationareplacedbymeansofthesecond.