简介:高压缩比率,高译码性能,和进步数据传播是为WebGIS的向量数据压缩算法的最重要的要求。满足这些要求,我们在场一条新压缩途径。这篇论文由把漂流坐标变换成整数坐标以多尺度的数据的产生开始。在屏幕上的变换的点和原来的点之间的距离在2个象素以内,这被证明,因此,我们的途径对顾客方面上的向量数据的可视化合适。整数坐标被传递给一个整数小浪变压器,并且高周波的系数由变压器生产了被正规哈夫曼代码编码。河数据和道路数据上的试验性的结果表明建议途径的有效性:为河数据的压缩比率罐头活动范围10%和20%为道路数据分别地。我们断定更多的注意需要被付到在包含一些点的弯曲之间的关联。
简介:Thispaperinvestigatesthemathematicfeaturesofnon-linearmodelsanddiscussestheprocessingwayofnon-linearfactorswhichcontributestothenon-linearityofanonlinearmodel.Onthebasisoftheerrordefinition,thispaperputsforwardanewadjustmentcriterion,SGPE.Last,thispaperinvestigatesthesolutionofanon-linearregressionmodelinthenon-linearmodelspaceandmakesthecomparisonbetweentheestimatedvaluesinnon-linearmodelspaceandthoseinlinearmodelspace.
简介:Weareinvolvedinanembarrassingsituationthatthelimitedcapa-bilityofautomatedfeatureextractionindigitalphotogrammetricsystemscannotsatisfytheincreasingneedsforrapidacquisitionofsemanticinformationforappli-cations.Facingthischallenge,anewtactic,Human-ComputerCollaborative(HCC)tactic,andacorrespondingnewmethod,Operator-ObjectDirected(OOD)method,areproposedforthedesignofasystemforfeatureextractionfromlargescaleaerialimages.Weholdthatinalmostalltechnicalcomplexsys-tems,fullautomationwillbeneithertechnicallyfeasiblenorsociallyacceptable.Thesystemshouldbedesignedtooptimizethroughthecooperativeoperationwithtwoagentsinthesystem:thehumanandthecomputer.
简介:学习的主要目的是用遥感和地理信息系统(GIS)与一条综合途径在Thirumanimuttar盆识别地下水潜力地区。LandsatTM30m分辨率数据和地志的地图的FCC图象被用来产生相似地质学,地形学,貌和貌密度,排水,排水密度,和斜坡学习区域印射的题目的地图。象Denudational山,结构的山,Bajadas,塌积的平原,Pediplain,深三角饰和冲积平原那样的很多个似地球形状的单位被观察了。一张合成地下水潜力地图作为基于地下水可获得性区域很高、高、中等、低、很低被产生了。盆上面、中间、下游为地下水作为潜在的地区被识别了探索。为地下水潜力地区证明的貌和交叉的貌的区域。产生的数据与领域检查被验证并且观察了在有一样的一致。
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