简介:<正>所谓3S技术即GPS、GIS、RS技术。GPS(全球定位系统)是英文缩写词NAVSTAR/GPS(NAVigationSystemTimeAndRanging/GlobalPositioningSystem)的简称。全称应为“测时测距导航系统/全球定位系统”。GPS是由美国研制,并投入实际应用的最新卫星定位系统。其主要目的是为飞机和船舶导航定位。也可以用于其它多种目的。GPS技术已在航空、航天、航海、军事、地质、石油、勘探、交通、测绘等领域得到广泛的应用。美国于1993年6月26日已将GPS21颗卫星和3颗备用卫星全部发射入轨。
简介:Theproblemsoftheearth'sgravityfields'visualizationarebothfocusandpuzzlecurrently.Aimingatmultiresolutionrendering,modelingoftheEarth'sgravityfields'dataisdiscussedinthepaperbyusingLODalgorithmbasedonQuadTree.First,thispaperemployedthemethodofLODbasedonQuadTreetodivideuptheregionalgravityanomalydata,introducedthecombinednodeevaluationsystemthatwascomposedofviewpointrelatedandroughnessrelatedsystems,andtheneliminatedtheT-cracksthatappearedamongthegravityanomalydatagridswithdifferentresolutions.Thetestresultsdemonstratedthatthegravityanomalydatagrids'renderingeffectswereliving,andthecomputationalpowerwaslow.Therefore,theproposedalgorithmwasasuitablemethodformodelingthegravityanomalydataandhaspotentialapplicationsinvisualizationoftheearth'sgravityfields.
简介:ByusingobservedCHAMPorbitephemeredesandMSISE-90dryairmodelandregardingtheearthasasphereandanellipsoidrespectively,phasedelaysaresimulatedandthesimulateddataareretrievedunderdifferentschemes.Thecomparisonbetweentheinvertedtemperatureprofilesandthemodeltemperatureprofilesshowsthatbyinvertingobserveddata,wewillgettemperatureresultswithlargeerrorsiftheeffectofEarth'soblatenessisomitted.Thecorrectionmethodisprovedtobeeffectivebecausethetemperatureerrorsdecreasedobviouslywiththismethod.
简介:Theclassificationaccuracyofthevariouscategoriesontheclassifiedremotelysensedimagesareusuallyevaluatedbytwodifferentmeasuresofaccuracy,namely,producer'saccuracy(PA)anduser'saccuracy(UA).ThePAofacategoryindicatestowhatextentthereferencepixelsofthecategoryarecorrectlyclassified,whereastheUAofacategoryrepresentstowhatextenttheothercategoriesarelessmisclassifiedintothecategoryinquestion.Therefore,theUAofthevariouscategoriesdeterminesthereliabilityoftheirinterpretationontheclassifiedimageandismoreimportanttotheanalystthanthePA.ThepresentinvestigationhasbeenperformedinordertodetermineifthereoccursimprovementintheUAofthevariouscategoriesontheclassifiedimageoftheprincipalcomponentsoftheoriginalbandsandontheclassifiedimageofthestackedimageoftwodifferentyears.WeperformedtheanalysesusingtheIRSLISSIIIimagesoftwodifferentyears,i.e.,1996and2009,thatrepresentthedifferentmagnitudeofurbanizationandthestackedimageofthesetwoyearspertainingtoRanchiarea,Jharkhand,India,withaviewtoassessingtheimpactsofurbanizationontheUAofthedifferentcategories.TheresultsoftheinvestigationdemonstratedthatthereoccurssignificantimprovementintheUAoftheimperviouscategoriesintheclassifiedimageofthestackedimage,whichisattributabletotheaggregationofthespectralinformationfromtwicethenumberofbandsfromtwodifferentyears.Ontheotherhand,theclassifiedimageoftheprincipalcomponentsdidnotshowanyimprovementintheUAascomparedtotheoriginalimages.
简介:OnthebasisofthecharacteristicoftheperfectspatialdistributionoftheT/Paltimeterdata,aspatialharmonictidalanalysisisperformed,whichtransferstidalharmonicconstantsHandgofeachconstituentintoapairofparameters:thecosinepartUandsinepartV.Andeachpartisexpandedintoapolynomial.Thepolynomialcoefficientsareestimatedwithaltimeterdataupontheleastsquarescriteria.ThusthemodelsofprincipaltidalwavesintheSouthChinaSeaareestablished.72cyclesofT/Pdatafromcycle11through82areincludedinthecalculation.Themodelsareevaluatedwithdifferentapproachesanddataset.Theconclusionsarethatthetidemodescanprovidepartialtideamplitudeswith3cmaccuracy,andthatphaselagsdeviationofthosetideswithamplitudelargethan10cmarewithin±10°.
简介:通过对3S技术、北斗技术、网格技术和网络技术等相关技术的集成协同研究,搭建了西南地区野外地质调查生产调度、突发事件、应急处置的远程服务网格结点体系和管理平台,建立了基于3S技术的野外地质工作管理与安全保障服务的4级结构体系.在西南地区开展了不同地貌特征、不同类型项目的示范应用,形成了以“成都地质调查中心→省级地调院(野外工作站)→野外驻地→单兵”为主线的野外地质工作管理与服务模式,实现了野外地质调查工作的实时动态管理与服务,最大化地保障了地质队员的人身安全,构建了现代野外地质工作管理与服务的新模式,对全面推进地质工作的现代化具有重要意义.
简介:一个算法(微分模式)为沿着T/P的潮汐的分析追踪的泛音的改进被介绍,在哪个在邻近的点的观察海面高度之间的差别作为观察被拿。另外,观察方程与转线路分析的结果被抑制;参数估计被最少的广场在0.1°纬度间隔执行。盖住中国海和西北太平洋的周期10~330T/P高度表数据(2°-50°N,105°-150°E)为精制沿着轨道泛音被采用在8474个点的12成分的潮汐的分析,和泛音常数被获得,它显示算法罐头高效地在高度表观察移开非潮汐的效果,并且改进潮参数的精确。而且,沿着测高法轨道的参数比传统的算法获得的那些代表更光滑的分布。在从11厘米的潮汐的高度模型和到1.3厘米的观察还原剂之间的恰当的错误的根平均数广场。