简介:Lidarisaneffectivetoolforremotelymonitoringtargetorobject,butthelidarsignalisoftenaffectedbyvariousnoisesorinterferences.Therefore,detectingtheweaksignalsburiedinnoisesisafundamentalandimportantprobleminthelidarsystems.Inthispaper,aneffectivenoisereductionmethodcombiningwaveletimprovedthresholdwithwaveletdomainspatialfiltrationispresentedtodenoisepulselidarsignalandisinvestigatedbydetectingthesimulatingpulselidarsignalsinnoise.Thesimulationresultsshowthatthismethodcaneffectivelyidentifytheedgeofsignalanddetecttheweaklidarsignalburiedinnoises.
简介:Background:Monitoringforesthealthandbiomassforchangesovertimeintheglobalenvironmentrequirestheprovisionofcontinuoussatelliteimages.However,opticalimagesoflandsurfacesaregenerallycontaminatedwhencloudsarepresentorrainoccurs.Methods:Toestimatetheactualreflectanceoflandsurfacesmaskedbycloudsandpotentialrain,3DsimulationsbytheRAPIDradiativetransfermodelwereproposedandconductedonaforestfarmdominatedbybirchandlarchinGenheCity,DaXing’AnLingMountaininInnerMongolia,China.Thecanopyheightmodel(CHM)fromlidardatawereusedtoextractindividualtreestructures(location,height,crownwidth).Fieldmeasurementsrelatedtreeheighttodiameterofbreastheight(DBH),lowestbranchheightandleafareaindex(LAI).SeriesofLandsatimageswereusedtoclassifytreespeciesandlandcover.MODISLAIproductswereusedtoestimatetheLAIofindividualtrees.CombiningalltheseinputvariablestodriveRAPID,high-resolutionopticalremotesensingimagesweresimulatedandvalidatedwithavailablesatelliteimages.Results:Evaluationsonspatialtexture,spectralvaluesanddirectionalreflectancewereconductedtoshowcomparableresults.Conclusions:Thestudyprovidesaproof-of-conceptapproachtolinklidarandMODISdataintheparameterizationofRAPIDmodelsforhightemporalandspatialresolutionsofimagereconstructioninforestdominatedareas.
简介:摘要:机载语音通讯可以极大的提高飞行任务的执行效率、降低软件的操作难度等。本文通过RTP进行音频流传输,FFmpeg实现多路通道混音效果,在地面设计了一套仿真环境模拟机载语音通讯,实现了机载席位间点呼、组网通话功能。
简介:摘要:本篇文章主要对航空机载外观检验的主要内容进行了全面的阐述,并且有效的总结和分析了在现实工作中,经常出现的外观质量问题,以实际出现问题的具体类型和方式作为实际的依据,与此同时,将其与实际的工作结合在一起,进而将有效的质量控制措施制定进来,有效的控制机载成品的总体质量。