简介:ThepolicyoftheChinesegovernmentconcerningthehorizontalexpansionofthecultivatedlandthroughthereclamationofdesertsoilsresultinatotalincreaseof665.985km2duringtheperiod1987-1999inNorthShaanxi.Thisincreaseislessthanthelossinarablelandbyurbanization.Theacceleratedrateofchangeinagriculturalareascallsformorerapidsurveysofurbanizationandlossofarableland.Remotesensinghasanumberofadvantagesoverground-basedmethodsforsuchsurveys.Themulti-scaleconceptofremotesensingdatahelpusstudytheprobleminfourtowns.Severalmapswereproducedtoanalyzethesituationofurbancoverageindifferenttimes.Theevaluationofthestatus,rateandriskofurbanizationarebasedonanacceptedaverageofurbanincreaseas2%ofpopulationgrowthperyear.
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: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:高度表数据和海洋潮模型的质量对沿海的严肃异例的恢复批评。在这贡献,三重新追踪方法(阀值,改进阀值和Beta-5)与在一个浅水区域上改进高度表数据的目的被调查。比较显示改进阀值是在中国海上的最好重新追踪的方法。二个海洋潮模型,NAO99b和CSR4.0,被分析。不同的潮模型在处理高度表数据使用了的结果表演可以导致差别在恢复沿海的严肃异例的超过10mGal。另外,NAO99b是比在中国海的浅水区域上的CSR4.0更合适的。最后,在中国海上的严肃异例被最少的广场搭配从重新追踪的Geosat/GM和ERS-1/GM数据计算。有shipbornegravimetry数据的比较证明从重新追踪的数据的严肃异例比从non-retracked数据的那些显著地优异。当另外的二导出高度表的严肃当模特儿,我们的结果有一样的顺序:Sandwell&Smith(V16)和DNSC08。
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:光合地活跃的放射(同等)的大小,为模仿植物生长和生产率不可缺少,通常是很少见的。这研究试图为估计在波伊昂·莱克公民自然保护区以内到达地球表面的每日的同等比较二个推测和推测插值方法,中国。在南昌气象学的车站的每天全球的太阳的放射记录和在在波伊昂·莱克附近的九个气象学的车站的每日的阳光持续时间大小被获得完成目的。使用的同等的二个推测方法记录了并且估计分别地,在自然保护区附近的南昌车站和三个车站(Yongxiu,Xingzi和Duchang)的全球太阳的放射被执行并且联合triangulated的一个空间插值方法不规则的网络(锡)和反的距离weighting(IDW)被实现估计每日的同等。用同等的三个方法的表演评估在Dahuchi保存车站测量了(测量=的天数字105天)揭示了那:(1)空间插值方法完成了最好的同等评价(R2=0.89,s.e=0.99,F=830.02,P<0.001);(2)来自南昌车站的推测方法获得了不偏的结果(R2=0.88,s.e=0.99,F=745.29,P<0.001);然而,(3)从Yongxiu,Xingzi和Duchang车站的推测方法不对为他们的偏导的评价的这个特定的地点合适。就支持推测和插值方法的假设和原则而言,作者断定空间插值方法比推测方法生产更可靠的结果并且在所有测试方法,和更多的同等大小保持最大的潜力应该被记录评估季节,为他们到波伊昂·莱克的整个自然保护区的申请的这些模型的每年、空间的稳定性。
简介:Itisnecessarytoestimateheavymetalconcentrationswithinsoilsforunderstandingheavymetalcontaminationsandforkeepingthesustainabledevelopmentsofecosystems.Thisstudy,withthefloodplainalongLe'anRiveranditstwobranchesinJiangxiProvinceofChinaasacasestudy,aimedtoexplorethefeasibilityofestimatingconcentrationsofheavymetallead(Pb),copper(Cu)andzinc(Zn)withinsoilsusinglaboratory-basedhyperspectraldata.Thirtysoilsampleswerecollected,andtheirhyperspectraldata,soilorganicmattersandPb,CuandZnconcentrationsweremeasuredinthelaboratory.Thepotentialrelationsamonghyperspectraldata,soilorganicmatterandPb,CuandZnconcentrationswereexploredandfurtherusedtoestimatePb,CuandZnconcentrationsfromhyperspectraldatawithsoilorganicmatterasabridge.Theresultsshowedthattheratioofthefirst-orderderivativesofspectralabsorbanceatwavelengths624and564nmcouldexplain52%ofthevariationofsoilorganicmatter;thesoilorganicmattercouldex-plain59%,51%and50%ofthevariationofPb,CuandZnconcentrationswithestimatedstandarderrorsof1.41,48.27and45.15mg·kg-1;andtheabsoluteestimationerrorswere8%-56%,12%-118%and2%-22%,and50%,67%and100%ofthemwerelessthan25%forPb,CuandZnconcentrationestimations.Weconcludedthatthelaboratory-basedhyperspectraldataholdpotentialsinesti-matingconcentrationsofheavymetalPb,CuandZninsoils.Moresamplingpointsorotherpotentiallinearandnon-linearregressionmethodsshouldbeusedforimprovingthestabilitiesandaccuraciesoftheestimationmodels.