简介:IntroductionDuringtheteachingandlearningprocess,teachersoftencheckhowmuchstudentshaveunderstoodthroughwrittenassignments.InthisarticleI’dliketodescribeonemethodofcorrectingstudents’writtenworkbyusingavarietyofsymbolstoindicatewherestudentshavegonewrong,thenaskingstudentstocorrecttheirworkthemselves.
简介:Oneofthemaindriversforintelligenttransportationsystemsissafety.Adaptivecruisecontrol,asacommonsolutionfortrafficsafety,hasextendedfromradarstocameras.Duetohighmobilityofvehiclesandunevennessofroads,thepicturequalityofcamerashasbeengreatchallengesforcamera-basedadaptivecruisecontrol.Inthispaper,animagedistortioncorrectionalgorithmisaddressed.Ourmethodisbasedonopticalflowtechnologywhichisnormallyappliedinmotionestimationandvideocompressionresearch.Wearethefirsttoattempttoadaptitinimagedistortioncorrection.Twoopticalflowapproaches,theLucas-KanademethodandtheHorn-Schunckmethod,areselectedandcompared.Theprocedureofimagedistortioncorrectionusingtheopticalflowmethodhasbeentestedbybothsynthetictestimagesandcameraimages.TheexperimentalresultsshowthattheLucas-Kanademethodismoresuitableinthecorrectionofimagedistortion.
简介:TheeffectsofmagnituderoundingandofthepresenceofnoiseintheroundedmagnitudesontheestimationoftheGutenberg–Richterb-valueareexplored,andthewaystocorrectfortheseeffectsareproposed.Fortypicalvalues,b=1androundingintervalDM=0.1,theroundingerrorisapproximately-10-3anditcanbecorrectedtoanegligibleapproximately-10-5.Forthesametypicalvalues,theeffectofnoisecanbelarger,dependingonthecharacteristicsofthenoisedistribution;fornormallydistributednoisewithstandarddeviationr=0.1,thecorrectb-valuemaybeunderestimatedbyafactor*0.97.
简介:Thealternatecombinationalapproachofgeneticalgorithmandneuralnetwork(AGANN)hasbeenpresentedtocorrectthesystematicerrorofthedensityfunctionaltheory(DFT)calculation.IttreatstheDFTasablackboxandmodelstheerrorthroughexternalstatisticalinformation.Asademonstration,theAGANNmethodhasbeenappliedinthecorrectionofthelatticeenergiesfromtheDFTcalculationfor72metalhalidesandhydrides.ThroughtheAGANNcorrection,themeanabsolutevalueoftherelativeerrorsofthecalculatedlatticeenergiestotheexperimentalvaluesdecreasesfrom4.93%to1.20%inthetestingset.Forcomparison,theneuralnetworkapproachreducesthemeanvalueto2.56%.Andforthecommoncombinationalapproachofgeneticalgorithmandneuralnetwork,thevaluedropsto2.15%.Themultiplelinearregressionmethodalmosthasnocorrectioneffecthere.
简介:TheionospherictimedelayisoneofthemainerrorsourcesinC/AcodeGPSnavigationandpositioningapplications.Inthispaper,amethodisproposedforreal-timedual-frequencyionospherictime-delaycorrectingusingaC/AcodeGPSreceiver,andtheprincipleofthecircuitblockdiagramforthismethodisanalyzedwithitsfeasibilitytheoreticallydemonstrated.