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

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  • 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.

  • 标签: Nasopharyngeal swabs Nucleic acids Efficiency Designation
  • 简介:Opticalperformancemonitoringusingasynchronousopticalorelectricalsamplinghasgainedconsiderableattention.Relativeclockwanderbetweendatasignalandsamplingsourceisatypicaloccurrenceinsuchsystems.Amethodforthequantitativemonitoringoftherelativeclockwanderinasynchronousopticalundersamplingsystemispresented.Withaseriesofsimulations,theclockwandersrecoveredusingthismethodareingoodagreementwiththepresetclockwandersofdifferentamountsandfrequenciesforbothRZandNRZsignals.Hence,thereliabilityandrobustnessofthemethodareproven.

  • 标签: 时钟信号 采样系统 异步 测相 性能监控 监测方法
  • 简介:Compressivesensingisarevolutionaryideaproposedrecentlytoachievemuchlowersamplingrateforsignals.Intheimageapplicationwithlimitedresourcesthecameradatacanbestoredandprocessedincompressedform.Analgorithmformovingobjectandregiondetectioninvideousingacompressivesamplingisdeveloped.Thealgorithmestimatesmotioninformationofthemovingobjectandregionsinthevideofromthecompressivemeasurementsofthecurrentimageandbackgroundscene.Thealgorithmdoesnotperforminversecompressiveoperationtoobtaintheactualpixelsofthecurrentimagenortheestimatedbackground.Thisleadstoacomputationallyefficientmethodandasystemcomparedwiththeexistingmotionestimationmethods.Theexperimentalresultsshowthatthesamplingratecanreduceto25%withoutsacrificingperformance.

  • 标签: 视频压缩 移动物体 抽样框 侦测 数据图像 采样算法
  • 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

  • 标签: 地上生物量 取样策略 评价 估算 采样策略 分层抽样
  • 简介:Point-basedsurfacehasbeenwidelyusedincomputergraphicsformodeling,animation,visualization,simulationofliquidandsoon.Furthermore,particle-basedapproachcandistributethesurfacesamplingpointsandcontrolitsparametersaccordingtotheneedsoftheapplication.Inthispaper,weexamineseveralkindsofalgorithmspresentedoverthelastdecades,withthemainfocusonparticlesamplingtechnologiesforimplicitsurface.Therefore,weclassifyvariousalgorithmsintocategories,describemainideasbehindeachcategories,andcomparetheadvantagesandshortcomingsofthealgorithmsineachcategory.

  • 标签: 粒子系统 隐式曲面 采样技术 采样点 算法比较 图形建模
  • 简介:Adoptingaprincipleof“check-acceptforthefirstrank,inspectionforthesecondrank”,thispaperbrieflydiscussestherationaleofthesamplinginspectionandthesamplinginspectionschemestodigitalproductsinGIS.TheOCcurveisdrawntoexplainthedeficiencyofthepercentsamplinginspection.Meanwhile,themethodofOneTimeLimitingQualityofcountselectionispresentedastheinspectionschemeforproductiondepartmentswhilethemethodofOneTimeAfter-inspectionMeanPercentDefectiveUpperLimitofcountselectionisforacceptancedepartments.

  • 标签: sampling INSPECTION DIGITAL PRODUCTS GIS
  • 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。

  • 标签: BERNSTEIN多项式 随机抽样 散乱数据 操作人员 切比雪夫 均匀分布
  • 简介:ChinatoConductOnePercentPopulationSamplingSurvey¥//ChinawillconductaonepercentpopulationsamplingsurveyonOctober1,1995,accordi...

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

  • 标签: LEISURE TRADING Sampling Hangzhou sized SPEND
  • 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。

  • 标签: 激光雷达系统 波形信号 消噪方法 取样 机载 去噪方法
  • 简介:ThepaperpresentsandprovesanapproximateoptimalrelationshipbetweensamplesizenandacceptancenumbercinthesamplingplansunderimperfectinspectionwhichminimizetheBayesianrisk.TheconclusiongeneralizestheresultobtainedbyA.Haldontheassumptionthattheinspectionisperfect.

  • 标签: sampling INSPECTION sampling PLAN imperfect INSPECTION
  • 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。

  • 标签: 自适应采样 间接照明 方差分析 复用 光路 全局光照算法
  • 简介:1.IntroductionAnimportsnttopicinQualityColltrolisthestudyofacceptancesamplingplan.Foravariablesamplingplan,thequalityofanitemismeasuredbyarandomvariable.Todesignavariablesamplingplanistodeterminethesamplesizeandthespecilicstionlicit(s).Manyschemeshav...

  • 标签: Single sampling PLAN the Weibull distribution
  • 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.

  • 标签: URBAN GREENLAND AUTOCORRELATION ANALYSIS SPATIAL STRATIFIED