简介：Bytakingtheurbangreenlandastestingobjective,theGeoEye-1fusionimageasbackground,andusingMoran’sindex,thecorrelativityofgreenlandunitshasbeenmeasured.Then,thepresamplingwasconductedbasedonthemeasuredcorrelativity,thesystematicsamplingdesignhasbeencarriedoutattheprecision95%and85%.ByusingofKriginginterpolationmethod,theweightofdifferenttypeofgreenlandhasbeendividedintothestratifications.Throughthestratifiedsampling,theestimationofgreenlandcoveragehasbeenobtained.Theresultsshowthattheurbangreenlandcoverageareais14.81km~2,accountingfor27.73%ofallurbanlandareas.Comparedwiththecommonsamplingmethod,theprecisionofthatincreasedabout3%.Thismethodcanalsobeutilizedinmonitoringdynamicvariationofurbangreenlandwiththerealtimeimages.

简介：SpatialobjectandspatialrelationshiparetwobasicconceptsofGIS.Spatialobjectisthedigitalrepresentationofgeographicalentityorphenomenon,whichformsthebasisfordatamanagementandanalysis;spatialrelationshipistheconnexionbetweenspatialobjectswhengeometricpropertiesareconsidered.Thecommonlyusedclassificationofspatialobjectsaspoints,linesandareasismathe-maticallystrict,andsuitablefordatamanagement,butabittoogeneralizedforrepresentingrealentitiesandextractingspatialrelationships.Agoodclassificationmodelshouldnotonlybegoodforrepresentingrealentities,butalsogoodforre-vealingspatialrelationships,thereforegoodforformalizingspatialanalyses.

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简介：Thispaperattemptstoregardspatialrelationtransformationasanimportantprocessinmapgener-alization.Thespatialrelationgenerali-zationcanbedividedintothecompo-nentsofabstraction:topology,dis-tanceandorientation.Theconcept‘spatialrelationresolution'isintro-ducedtodescribetheconstraintsofrelativespatialrelation.Onthebasisofnineintersectionmodels,thecardi-naldirectionmodelsandtheiso-dis-tance-relationmodels,thispapergivesthreesortsofrelationresolutionrepre-sentationsfortopological,distanceandorientationrelation,respectively.Twomappingimplementationsinmapgen-eralizationisdiscussed.

简介：Asaspecialshift-invariantspaces,splinesubspacesyieldmanyadvantagessothattherearemanypracticalapplicationsforsignalorimageprocessing.Inthispaper,wepayattentiontothesamplingandreconstructionprobleminsplinesubspaces.Weimprovelowerboundofsamplingsetconditionsinsplinesubspaces.Basedontheimprovedexplicitlowerbound,aimprovedexplicitconvergenceratioofreconstructionalgorithmisobtained.Theimprovedconvergenceratiooccupiesfasterconvergenceratethanoldone.Attheend,somenumericalexamplesareshowntovalidateourresults.

简介：AbstractUpper respiratory tract samples are the most commonly used samples for coronavirus disease 2019 (COVID-19) diagnosis. The samples collected from the nasopharynx are preferred for viral nucleic acids detection. Commercial nasopharyngeal swabs (NPSs) are the major factor that influences the sampling quality. We here evaluated the acceptability and efficiency of NPSs from five manufacturers by examining the concentration of glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH) retrieved from the swabs using the RT-PCR method. Significant different concentrations of GAPDH were detected, ranged from 4.36 × 108 copies/mL to 6.98 × 1010 copies/mL among the five swabs (P < 0.05). The designation of the swab head, with or without tip expansion, had limited influence on the collection efficiency. The discrepancy among the NPSs emphasized the improvement of the swab head material.

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简介：Opticalperformancemonitoringusingasynchronousopticalorelectricalsamplinghasgainedconsiderableattention.Relativeclockwanderbetweendatasignalandsamplingsourceisatypicaloccurrenceinsuchsystems.Amethodforthequantitativemonitoringoftherelativeclockwanderinasynchronousopticalundersamplingsystemispresented.Withaseriesofsimulations,theclockwandersrecoveredusingthismethodareingoodagreementwiththepresetclockwandersofdifferentamountsandfrequenciesforbothRZandNRZsignals.Hence,thereliabilityandrobustnessofthemethodareproven.

简介：Compressivesensingisarevolutionaryideaproposedrecentlytoachievemuchlowersamplingrateforsignals.Intheimageapplicationwithlimitedresourcesthecameradatacanbestoredandprocessedincompressedform.Analgorithmformovingobjectandregiondetectioninvideousingacompressivesamplingisdeveloped.Thealgorithmestimatesmotioninformationofthemovingobjectandregionsinthevideofromthecompressivemeasurementsofthecurrentimageandbackgroundscene.Thealgorithmdoesnotperforminversecompressiveoperationtoobtaintheactualpixelsofthecurrentimagenortheestimatedbackground.Thisleadstoacomputationallyefficientmethodandasystemcomparedwiththeexistingmotionestimationmethods.Theexperimentalresultsshowthatthesamplingratecanreduceto25%withoutsacrificingperformance.

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简介：Background:Dependingontreeandsitecharacteristicscrownbiomassaccountsforasignificantportionofthetotalabovegroundbiomassinthetree.Crownbiomassestimationisusefulfordifferentpurposesincludingevaluatingtheeconomicfeasibilityofcrownutilizationforenergyproductionorforestproducts,fuelloadassessmentsandfiremanagementstrategies,andwildfiremodeling.However,crownbiomassisdifficulttopredictbecauseofthevariabilitywithinandamongspeciesandsites.Thustheallometricequationsusedforpredictingcrownbiomassshouldbebasedondatacollectedwithpreciseandunbiasedsamplingstrategies.Inthisstudy,weevaluatetheperformancedifferentsamplingstrategiestoestimatecrownbiomassandtoevaluatetheeffectofsamplesizeinestimatingcrownbiomass.Methods:Usingdatacollectedfrom20destructivelysampledtrees,weevaluated11differentsamplingstrategiesusingsixevaluationstatistics:bias,relativebias,rootmeansquareerror(RMSE),relativeRMSE,amountofbiomasssampled,andrelativebiomasssampled.Wealsoevaluatedtheperformanceoftheselectedsamplingstrategieswhendifferentnumbersofbranches(3,6,9,and12)areselectedfromeachtree.Treespecificloglinearmodelwithbranchdiameterandbranchlengthascovariateswasusedtoobtainindividualbranchbiomass.Results:Comparedtoallothermethodsstratifiedsamplingwithprobabilityproportionaltosizeestimationtechniqueproducedbetterresultswhenthreeorsixbranchespertreeweresampled.However,thesystematicsamplingwithratioestimationtechniquewasthebestwhenatleastninebranchespertreeweresampled.Underthestratifiedsamplingstrategy,selectingunequalnumberofbranchesperstratumproducedapproximatelysimilarresultstosimplerandomsampling,butitfurtherdecreasedRMSEwheninformationonbranchdiameterisusedinthedesignandestimationphases.Conclusions:UseofauxiliaryinformationindesignorestimationphasereducestheRMSEproducedbyasamplingstrategy.Howe

简介：Point-basedsurfacehasbeenwidelyusedincomputergraphicsformodeling,animation,visualization,simulationofliquidandsoon.Furthermore,particle-basedapproachcandistributethesurfacesamplingpointsandcontrolitsparametersaccordingtotheneedsoftheapplication.Inthispaper,weexamineseveralkindsofalgorithmspresentedoverthelastdecades,withthemainfocusonparticlesamplingtechnologiesforimplicitsurface.Therefore,weclassifyvariousalgorithmsintocategories,describemainideasbehindeachcategories,andcomparetheadvantagesandshortcomingsofthealgorithmsineachcategory.

简介：Adoptingaprincipleof“check-acceptforthefirstrank,inspectionforthesecondrank”,thispaperbrieflydiscussestherationaleofthesamplinginspectionandthesamplinginspectionschemestodigitalproductsinGIS.TheOCcurveisdrawntoexplainthedeficiencyofthepercentsamplinginspection.Meanwhile,themethodofOneTimeLimitingQualityofcountselectionispresentedastheinspectionschemeforproductiondepartmentswhilethemethodofOneTimeAfter-inspectionMeanPercentDefectiveUpperLimitofcountselectionisforacceptancedepartments.

简介：在这份报纸，multivariate伯恩斯坦多项式定义在上一单一当由允许采样操作员在散布地点发生的采样操作员，和归纳被学习，被看。随机、确定的方面在学习被使用。在随机的方面上，为采样操作员的Chebyshev类型估计被建立。在确定的方面上，联合一致分发和差异方法的理论，接近的连续功能和L的率<啜class=“a-plus-plus”>为这些操作符的p集中分别地被学习。

简介：ＣｈｉｎａｔｏＣｏｎｄｕｃｔＯｎｅＰｅｒｃｅｎｔＰｏｐｕｌａｔｉｏｎＳａｍｐｌｉｎｇＳｕｒｖｅｙ￥／／ＣｈｉｎａｗｉｌｌｃｏｎｄｕｃｔａｏｎｅｐｅｒｃｅｎｔｐｏｐｕｌａｔｉｏｎｓａｍｐｌｉｎｇｓｕｒｖｅｙｏｎＯｃｔｏｂｅｒ１，１９９５，ａｃｃｏｒｄｉ...

简介：<正>Aftermorethan2,000yearsofhistoryasatradingcentreandcommu-nicationshubontheBeijing-HangzhouGrandCanal(firstduginthe5thcenturyBC),Huai’anhasacquiredanairofoldmoneyandmellowleisure.Itmustbeoneoffewsmall-sizedcitieswherepeopleareashappytospendtheirleisuretimeinoneofthedozensofopen-airteahousesorrestaurantsbythewaterasinanair-conditionedshoppingmall.

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简介：这份报纸描述使用条纹原则的一个完整的波形采样激光雷达系统。基于原来的条纹的边察觉，信号被建议的一种降噪的方法。这个方法与另外的降噪的方法相比，例如维纳过滤，吝啬的过滤并且中部的过滤。建议降噪的方法为处理波形信号是更有效的，这被发现。

简介：ThepaperpresentsandprovesanapproximateoptimalrelationshipbetweensamplesizenandacceptancenumbercinthesamplingplansunderimperfectinspectionwhichminimizetheBayesianrisk.TheconclusiongeneralizestheresultobtainedbyA.Haldontheassumptionthattheinspectionisperfect.

简介：Ortho_imageswillfullybeintegratedinGIS.Nodoubt,GISforgeneralpurposeisusablewithouttheintegrationofortho_imagesandotherrasterdata.ForsmallGISprojectsitmaybesufficienttostoreinformationassimplefiles.Whendatavolume,however,becomeslargeandthenumberofdatausersbecomesmorethanafew,thedatabasemanagementsystembecomesthemostimportantcomponent.Forinstance,thebasicdesignofGeoStarisbasedontheClient/ServerarchitectureandusinglargeRDBSandOODBStomanagetherasterandvectordatasuchasgraphicdata,attributedata,imagedataandDEMatthesameframework,whichisathoroughandseamlessintegratedsolutionforGISapplications.Thebriefstructureofdatabase,whichisreallyhybridandintegrated,isshowninFig.1.　　Inordertoprovidemoreefficientdataaccessorbrowseforalargearea,thevectordataisorganizedaccordingtotheclassifiedspatialindexbasedonanextendedquadtreecodestoredasclusterrelatedtothefeaturesize,asshowninFig.2.TherasterdatalikeimageandDEMisorganizedinpyramidgrid_dedmanner(Fig.3).EspeciallywearefacingtheproblemofmultiscaledatabaseswithindifferentcoordinatesystemsanddifferentmapprojectionsinChina,themoresophisticateddatabasesintegrationmethodthereforehastobedevelopedtodealwiththesocalled“crossingtheprojectionzone'problem.