学科分类
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11 个结果
  • 简介:ThepurposeofthispaperistostudytheRSdatawebservicesandrelatedsubjectsofdatastorageanddatamanagement.Basedonananalysisofthepresentsituationanddevelopmenttrendofstorageandmanagementofrasterdataandwebservicetechnology,amanagementandservicesystemarchitectureforRemoteSensingrasterdatabasedonwebservicetechnologieswasdeveloped,theimplementationmethodologiesofthekeytechnologyofthesystemwereexploredandaprototypeofthesystemwasillustrated.

  • 标签: 遥感技术 光栅数据 管理系统 网络技术 服务器
  • 简介:Thedevelopmentofhigh-resolutionremotesensingimagingtechnologyprovidesanewwaytothelarge-scaleestimationofforestcanopydensity.Thetraditionalinversionmethodsforcanopydensityonlyusespectralortopographicalfeaturesofremotesensingimages.However,duetotheexistenceofthedifferentthingwithsamespectrumandthesamethingwithdifferentspectrumphenomena,itisdifficulttoimprovetheestimationaccuracyofcanopydensity.Basedonspectrumandothertraditionalfeatures,thispapercombinestexturefeaturesofremotesensingimagestoestimatecanopydensity.Firstly,thegraylevelco-occurrencematrix(GLCM)texturefeaturesarecomputedusingobjectbasedmethod.Then,theprincipalcomponentanalysis(PCA)methodisappliedincorrelationanalysisanddimensionreductionoftexturefeatures.Finally,spectrumandtopographicalfeaturestogetherwithtexturefeaturesareintroducedintostepwiseregressionmodeltoestimatecanopydensity.Theexperimentalresultsshowedthatcomparedwiththetraditionalmethodonlybasedonspectrumortopographicalfeatures,themethodcombinedwithtexturefeaturesgreatlyimprovedtheestimationaccuracy.Thecoefficientofdetermination(adjustedR~2)increasedfrom0.737to0.805.Theestimationaccuracyincreasedfrom81.03%to84.32%.

  • 标签: CANOPY density TEXTURE GRAY level cooccurrence
  • 简介:InordertoprovideascientificbasisforriceyieldestimationandimprovetheacouracyofyieldestimationinZhejiangProvince,Regionalizationindicesforriceyieldestimationbyremoesensing(RS)intheprovinceweredeterminedbyconsjderingthespecialfeaturesofyieldestimationbyRS,andbasedonanalysisofthenaturalconditionsofZhejiangProvince,Theindicesdeterminedincludedricecroppingsystem,agroclimate,landform,surfacefeaturesturctureandriceyieldlevel,wherericeplantingsystemwasconsideredasthemianone,ThenreionalizationfroriceyieldestimationbyRSwascompletedbyspatialneighboringanalysiswiththeGeographicalInfromationSystem(GIS)technologycombinedwithusigoftreealgorithmTheprovincewasdividedintotworegions,i.e.,thesingle-croppingriceregionwhichwassubdividedinto3regionsincludingthoseinmountainsofnorthewstZhejiang,waternetworkareaofnorthZhejiangandmountainsofsothZhejiang,anddouble-croppingriceregionwhichwassudividedinto5regionsincludingthoseonplainofnorthZhejiang,coastalplainsandhillsofsoutheastZhejiang,Jin-QuBasinofmiddleZhejiang,hillsofeastZhejiang,andhillsandmountainsofnorthewatZhejiang,thisregionaliztiontookthecountybordersastheregionboundaries,kepttheregionsconnectiveandmadetheadministrativregionsintegrityand,then,couldmeettherequirementsofriceyieldestimationbyRS,showingthattheresultswerequitesatisfying.

  • 标签: 地理信息系统 GIS 遥感 RS 产量预测 浙江
  • 简介:Remotesensingimagesshowaverypromisingperspectivefordistinguishingtreespecies,especiallythosewiththeveryhighresolutionrangingfrom1to4m.However,thetraditionalmethodologyforclassifyinglandcovertypes,solelydependingonspectralfeatures,whiletextureandotherspatialinformationareneglected,hastheweaknesssuchasinadequatelyutilizationofinformation,lowaccuraciesofclassification,etc.Consideringtothetexturedifferencesamongforestspecies,itismoreimportantforspatialinformationdescriptionofhigh-resolutionremotesensingimagetoimprovetheprecisionoftexturalfeatureschoosing.Inthisstudy,thefactorstoinfluencetheninetexturalfeatureschoosingwereanalyzedandtheresultsshowedthatthemovingwindowsizewasthemainfactortoaffecttheobtainingprocessesoftexturalfeaturesbasedonthegraylevelco-occurrencematrix(GLCM)method,andtheimagerywasthenclassifiedcombiningthemaximumlikelihoodclassification(MLC)methodwiththeoriginalspectralvaluesandtexturefeatures.First,thisstudyutilizedacorrelationanalysisoftheimagesfromaprincipalcomponentanalysis.Second,throughmultipleinformationsources,includingtextualfeaturesderivedfromthedata.Forthehigh-resolutionremotesensingimage,themostpropermovingwindowsizewasdeterminedfrom3×3to31×31.Classificationofthemajortreespeciesthroughoutthestudyarea(theSunYat-SenMausoleuminNanjing)wasundertakenusingtheMLC.Third,toaidforestresearch,classificationaccuracywasimprovedusingtheGLCM.Accordingtocorrelationsamongtexturesandrichnessofthedata,GLCMprovidedthebestwindowsizeandtexturalparameters.Resultsindicatedthatthetexturecharacteristicswereaddinthespectralcharacteristicstoimprovetheprecisionoftheresultsoftheclassification,19×19windowforbestwindow.Thetotalprecisioncanreach66.3226%,Kappacoefficientis0.5840.Eachtreespecieshasgreatlyimprovedaccuraciesoftheclassification.Bythecal

  • 标签: forest management tree species CLASSIFICATION moving
  • 简介:Keerqin沙土地位于在向东北平凡、内部的蒙古之间的过渡地面(42°41′-45°15′N,118°35′-123°30′E)在东北Chinaand,它被沙漠化严重影响。根据地球表面的配置和生态环境,植被,赤裸的砂土的职业比率和土壤质地的范围被使用地调查数据作为评估索引选择。Keerqin沙的沙漠化的评估索引系统被使用遥感数据建立,并且赤裸的砂土的职业比率被混合光谱模型获得。这个索引系统被域调查数据验证,结果显示它对Keerqin的thedesertification评估合适。

  • 标签: 含沙土壤 遥感技术 荒漠化 生态环境 水土流失
  • 简介:Usingthemulti-temporalLandsatdataandsurveydataofnationalresources,theauthorsstudiedthedynamicsofcultivatedlandandlandcoverchangesoftypicalecologicalregionsinChina.TheresultsofinvestigationshowedthatthewholedistributionofthecultivatedlandshiftedtoNortheastandNorthwestChina,andasaresult,theecologicalqualityofcultivatedlanddroppeddown.TheseacoastandcultivatedlandintheareaofYellowRiverMouthexpandedbyanincreasingrateof0.73km?a-1,withadepositingrateof2.1km?a-1.ThedesertificationareaofthedynamicofHorqinSandyLandincreasedfrom60.02%ofthetotallandareain1970sto64.82%in1980sbutdecreasedto54.90%inearly1990s.AstothechangeofNorthTibetlakes,thewaterareaoftheNamuLakedecreasedby38.58km2fromyear1970to1988,withadecreasingrateof2.14km2?a-1.

  • 标签: 遥感信息 耕地 土地覆盖变化 典型生态区 中国
  • 简介:Background:Remotesensing-basedinventoriesareessentialinestimatingforestcoverintropicalandsubtropicalcountries,wheregroundinventoriescannotbeperformedperiodicallyatalargescaleowingtohighcostsandforestinaccessibility(e.g.REDDprojects)andaremandatoryforconstructinghistoricalrecordsthatcanbeusedasforestcoverbaselines.Giventheconditionsofsuchinventories,thesurveyareaispartitionedintoagridofimagerysegmentsofpre-fixedsizewheretheproportionofforestcovercanbemeasuredwithinsegmentsusingacombinationofunsupervised(automatedorsemi-automated)classificationofsatelliteimageryandmanual(i.e.visualon-screen)enhancements.Becausevisualon-screenoperationsaretimeexpensiveprocedures,manualclassificationcanbeperformedonlyforasampleofimagerysegmentsselectedatafirststage,whileforestcoverwithineachselectedsegmentisestimatedatasecondstagefromasampleofpixelsselectedwithinthesegment.Becauseforestcoverdataarisingfromunsupervisedsatelliteimageryclassificationmaybefreelyavailable(e.g.Landsatimagery)overtheentiresurveyarea(wall-to-walldata)andarelikelytobegoodproxiesofmanuallyclassifiedcoverdata(sampledata),theycanbeadoptedassuitableauxiliaryinformation.Methods:Thequestionishowtochoosethesampleareaswheremanualclassificationiscarriedout.Wehaveinvestigatedtheefficiencyofone-per-stratumstratifiedsamplingforselectingsegmentsandpixels,wheretocarryoutmanualclassificationandtodeterminetheefficiencyofthedifferenceestimatorforexploitingauxiliaryinformationattheestimationlevel.Theperformanceofthisstrategyiscomparedwithsimplerandomsamplingwithoutreplacement.Results:OurresultswereobtainedtheoreticallyfromthreeartificialpopulationsconstructedfromtheLandsatclassification(forest/nonforest)availableatpixellevelforastudyarealocatedincentralItaly,assumingthreelevelsoferrorratesoftheuns

  • 标签: Spatially BALANCED sampling AUXILIARY INFORMATION
  • 简介:在干燥陆地的系统的木质的植物的地位是关键生态系统进程的一个基本决定因素。这地位监视在在干旱、半干旱的生态系统理解木质的植物的动力学起一个重要作用。现在的学习用遥感和地理信息系统技术和统计科学在伊朗决定了Zagros森林的精力。结果证明树的密度从10~53变化了?%根据半干旱的区域的地文学、气候的条件。在植被索引和森林密度之间的最好、最低的关联为全球环境监视索引被获得(GEMI;R2?=?0.94)和土壤调整植被索引(R2?=?0.81),分别地。GEMI被用来监视使用在一个10年的时期上改变的土地。结果显示出那2720?哈森林的2被人的干扰和耕种在也导致了肥沃的土壤层的损失的这个时期期间在陡峭的斜坡上破坏了。GEMI决定了区域与一树的生物资源并且有从没有华盖的区域的树的低生物资源密度的通常分开的边阶区域能盖住。结果用卫星在干旱、半干旱的艰巨森林区域揭示了对森林和植被盖子的那个评价数字数字和平常的采样服从于无常。一个成层的组织过程应该被建立增加评价的精确性。

  • 标签: 遥感和地理信息系统 全球环境监测 森林地区 木本植物 植物分布 半干旱生态系统
  • 简介:RemotesensingdatafromtheTerraModerate-ResolutionImagingSpectroradiometer(MODIS)andgeospatialdatawereusedtoestimategrassyieldandlivestockcarryingcapacityintheTibetanAutonomousPrefectureofGolog,Qing-hai,China.TheMODIS-derivednormalizeddifferencevegetationindex(MODIS-NDVI)datawerecorrelatedwiththeabovegroundgreenbiomass(AGGB)datafromtheabovegroundharvestmethod.RegionalregressionmodelbetweentheMODIS-NDVIandthecommonlogarithm(LOG10)oftheAGGBwassignificant(r2=0.51,P<0.001),itwas,there-fore,usedtocalculatethemaximumcarryingcapacityinsheep-unityearperhectare.Themaximumlivestockcarryingcapacitywasthenadjustedtothetheoreticallivestockcarryingcapacitybythereductionfactors(slope,distancetowater,andsoilerosion).Resultsindicatedthatthegrasslandconditionsbecameworse,withlowerabovegroundpalatablegrassyield,plantheight,andcovercomparedwiththeresultsobtainedin1981.Atthesametime,althoughtheactuallivestocknumbersdecreased,theystillexceededthepropertheoreticallivestockcarryingcapacity,andovergrazingratesrangedfrom27.27%inDarlagCountyto293.99%inBaimaCounty.Integratingremotesensingandgeographicalinformationsystemtechnologies,thespatialandtemporalconditionsofthealpinegrassland,trend,andprojectedstockingratescouldbeforecastedfordecisionmaking.

  • 标签: 地理信息系统技术 最大承载能力 理论载畜量 遥感数据 牧草产量 高寒草地
  • 简介:Theradialbasisfunction(RBF)emergedasavariantofartificialneuralnetwork.Generalizedregressionneuralnetwork(GRNN)isonetypeofRBF,anditsprincipaladvantagesarethatitcanquicklylearnandrapidlyconvergetotheoptimalregressionsurfacewithlargenumberofdatasets.Hyperspectralreffectance(350to2500nm)datawererecordedattwodifferentricesitesintwoexperimentfieldswithtwocultivars,threenitrogentreatmentsandoneplantdensity(45plantsm-2).Stepwisemultivariableregressionmodel(SMR)andRBFwereusedtocomparetheirpredictabilityfortheleafareaindex(LAI)andgreenleafchlorophylldensity(GLCD)ofricebasedonreffectance(R)anditsthreedifferenttransformations,thefirstderivativereffectance(D1),thesecondderivativereffectance(D2)andthelog-transformedre?ectance(LOG).GRNNbasedonD1wasthebestmodelforthepredictionofriceLAIandGLCD.TherelationshipsbetweendifferenttransformationsofreffectanceandriceparameterscouldbefurtherimprovedwhenRBFwasemployed.Owingtoitsstrongcapacityfornonlinearmappingandgoodrobustness,GRNNcouldmaximizethesensitivitytochlorophyllcontentusingD1.ItisconcludedthatRBFmayprovideausefulexploratoryandpredictivetoolfortheestimationofricebiophysicalparameters.

  • 标签: 径向基函数神经网络 广义回归神经网络 生物物理参数 水稻 模型估算 高光谱反射率
  • 简介:PhysiographyandsoilinMaeRimwatershed,ChiangMaiProvince,Thailandwereinvestigatedbyusingaerialphotographsandsatelliteimageinconjunctionwithfieldwork,andsoilinfiltrationrateandsoilshearresistanceweremeasuredinfield.ManyfactorsaffectingrunoffwereanalyzedusigtheIntegratedLandandWaterInformaitonSystem(ILWIS).Asaresult,amodeldeterminingfloodhazarwassetup.Threempsincludingrunoffcurvenumbermap,runoffcoefficentmap,andfloodinumdationmapwerecreated,Inaddition,thetimeofconcentrationwaspredicted.

  • 标签: 洪水危害预报 遥感 地理信息系统 土壤性质 表面流失系数 泰国