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.
简介:Opticalperformancemonitoringusingasynchronousopticalorelectricalsamplinghasgainedconsiderableattention.Relativeclockwanderbetweendatasignalandsamplingsourceisatypicaloccurrenceinsuchsystems.Amethodforthequantitativemonitoringoftherelativeclockwanderinasynchronousopticalundersamplingsystemispresented.Withaseriesofsimulations,theclockwandersrecoveredusingthismethodareingoodagreementwiththepresetclockwandersofdifferentamountsandfrequenciesforbothRZandNRZsignals.Hence,thereliabilityandrobustnessofthemethodareproven.
简介:Compressivesensingisarevolutionaryideaproposedrecentlytoachievemuchlowersamplingrateforsignals.Intheimageapplicationwithlimitedresourcesthecameradatacanbestoredandprocessedincompressedform.Analgorithmformovingobjectandregiondetectioninvideousingacompressivesamplingisdeveloped.Thealgorithmestimatesmotioninformationofthemovingobjectandregionsinthevideofromthecompressivemeasurementsofthecurrentimageandbackgroundscene.Thealgorithmdoesnotperforminversecompressiveoperationtoobtaintheactualpixelsofthecurrentimagenortheestimatedbackground.Thisleadstoacomputationallyefficientmethodandasystemcomparedwiththeexistingmotionestimationmethods.Theexperimentalresultsshowthatthesamplingratecanreduceto25%withoutsacrificingperformance.
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:ChinatoConductOnePercentPopulationSamplingSurvey¥//ChinawillconductaonepercentpopulationsamplingsurveyonOctober1,1995,accordi...
简介:<正>Aftermorethan2,000yearsofhistoryasatradingcentreandcommu-nicationshubontheBeijing-HangzhouGrandCanal(firstduginthe5thcenturyBC),Huai’anhasacquiredanairofoldmoneyandmellowleisure.Itmustbeoneoffewsmall-sizedcitieswherepeopleareashappytospendtheirleisuretimeinoneofthedozensofopen-airteahousesorrestaurantsbythewaterasinanair-conditionedshoppingmall.
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简介:ThepaperpresentsandprovesanapproximateoptimalrelationshipbetweensamplesizenandacceptancenumbercinthesamplingplansunderimperfectinspectionwhichminimizetheBayesianrisk.TheconclusiongeneralizestheresultobtainedbyA.Haldontheassumptionthattheinspectionisperfect.
简介:在这份报纸,我们基于间接轻路径复用学习一套全球照明算法的评价变化。这些算法通常在第一张通行证包含二张通行证,间接轻样品的一个小数字被产生并且评估,并且他们然后被很多重建样品在第二张通行证再使用。我们的分析证明重建样品的协变性在高重建率下面统治评价变化并且增加重建率不能有效地减少协变性。我们也发现协变性代表到到什么度,间接轻样品在重建期间被再使用。这分析激发我们设计启发式的接近协变性以及一个适应采样计划基于这对还原剂启发式显示的变化。我们为间接点亮在间接的轻地重建算法和排列轴的过滤算法验证我们的分析和适应采样计划。实验根据我们显示人工制品能极大地以类似的计算成本被减少的分析和表演。
简介:1.IntroductionAnimportsnttopicinQualityColltrolisthestudyofacceptancesamplingplan.Foravariablesamplingplan,thequalityofanitemismeasuredbyarandomvariable.Todesignavariablesamplingplanistodeterminethesamplesizeandthespecilicstionlicit(s).Manyschemeshav...
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.