简介：Althoughstimulusfrequencyotoacousticemissions(SFOAEs)havebeenusedasanon-invasivemeasureofcochlearmechanics,clinicalandexperimentalapplicationofSFOAEshasbeenlimitedbydifficultiesinaccuratelyderivingquantitativeinformationfromsoundpressuremeasuredintheearcanal.Inthisstudy,anovelsignalprocessingmethodformulticomponentanalysis(MCA)wasusedtomeasuretheamplitudeanddelayoftheSFOAE.Thisreportshowsthedelay-frequencydistributionoftheSFOAEmeasuredfromthehumanear.AlowlevelacousticalsuppressorneartheprobetonesignificantlysuppressedtheSFOAE,stronglyindicatingthattheSFOAEwasgeneratedatcharacteristicfrequencylocations.Informationderivedfromthismethodmayrevealmoredetailsofcochlearmechanicsinthehumanear.
简介：Thenearly30-yeareconomicgrowthmiraclebringstheconsequenttremendouspoor-richgapleadingstrongdrivesforsocialtransformationincurrentChina.Chinesetopleadershaverealizedtoincreasethepeoples'income,improvequalityoflifeandconstructa'harmonioussociety'askeymissionsespeciallyinrecent10years.Howtomeasureaharmonioussocietyisoneimportanttopicasdifferentmeasuresmayleadtodifferentdevelopmentpolicies.Thispaperoutlinesover10indicesrelevanttomeasureaharmonioussociety.Someareglobalindicators,whilesomearecontributedbydomesticresearchersandarousedebates.Mostofthoseindicatorsrequireconductingsurveysonsocialattitudesundermicrolevels,whichisalwaystimeconsumingwithproblemofdataquality.AsInternettechnologyadvancesprovidewaystorecordanddisseminatefreshcommunityideasandthoughtsconveniently,detectingtopicsoremotionsfromon-linepublicopinionsisbecomingatrendoronesupplementwaytoovercomethosedataacquisitionproblems.Thispaperdiscussesoneapproachtoon-linesocietalriskperceptionusinghotsearchwordsandBBSposts.Suchatrialaimstoprovideanotherwaytosocietalriskperceptiondifferentfromthoseintraditionalsociopsychologystudies.Challengesarealsoindicated.
简介：Wepresentarecentnumericalanalysisofimpedancemismatchtechniqueappliedtocarbonequationofstatemeasurements.Weconsiderhigh-powerlaserpulseswithaGaussiantemporalprofileofdifferentdurations.Weshowthatforthelaserintensity(≈1014W/cm2)andthetargetdesignconsideredinthispaperweneedtohavelaserpulseswithrise-timelessthan150ps.
简介：Anenergymeasurementsysteminalarge-aperturehighpowerlaserexperimentplatformisintroduced.Theentiremeasurementsystemincludesfivecalorimeters,whichcarryouttheenergymeasurementofthefundamentalfrequencybeforethefrequencyconversionunit,remainingfundamentalfrequency,remainingsecond-harmonics,third-harmonics,aswellastheenergybalancemeasurementafterthefrequencyconversionunit.Combinationalindirectcalibrationanddirectcalibrationareemployedtocalibratethesamplingcoefficientsofthecalorimeters.Theanalysisofthedatashowedthat,regardingtheenergybalancecoefficients,combinationalcalibrationapproachgivesahigherprecision,andleadstoanenergybalancewith1%;andregardingtheenergysamplingcoefficientsforthevariouswavelengthsafterthefrequencyconversion,theresultsfromdirectandcombinationalcalibrationareconsistent.Theuncertaintiesforallenergysamplingcoefficientsarewithin3%,whichguaranteesthereliabilityoftheenergymeasurementforthelaserfacility.
简介：Wemeasurethehalf-wavevoltageofLiNbO3phasemodulatorsina26-GHzwidebandfrequencyrange,andthenanalyzeitbythephasemodulationphotonicpeakgainlinkedtotheinterferometricdemodulation.Theopticalinterferometerisconstructedwithtwo50:50couplersandtwofiberarmswitha1-mdifferenceinfiberlength.Thephotoniclinkgainpeaksarefrequencydependent,asindicatedbythedifferentialtimedelayintheinterferometer.Theproceduredescribedisanewandpracticalhalf-wavevoltagemeasurementmethodthatcanaccuratelypredictthenonlinearfrequencycharacteristicsofthephasemodulator.Moreover,themethodcanbeappliedtovarioustypesofLiNbO3phasemodulators.
简介：Wepresentamethodthataccuratelymeasureslargeopticalsurfacesbeforepolishingusingalasertracker.Usingthescanningmodeofthelasertrackerconsiderablyimprovesmeasurementefficiencyandminimizesthedominanterrorscausedbyenvironmentalchange.WeusethismethodtomeasureaΦ1.3-masphericmirrorandobtainameasurementuncertaintyof0.72μm(rootmeansquare,RMS).
简介：Objectives:Polymerizationshrinkageofdentalcompositesremainsamajorconcerninrestorativedentistrybecauseitcanleadtomicro-crackingofthetoothanddebondingatthetooth-restorationinterface.Theaimofthisstudywastomeasurethefull-fieldpolymerizationshrinkageofdentalcompositesusingtheopticaldigitalimagecorrelation(DIC)methodandtoevaluatehowthemeasurementisinfluencedbythefactorsinexperimentsetupandimageanalysis.Methods:Fourcommercialdentalcomposites,PremiseDentine,Z100,Z250andTetricEvoCeram,weretested.Compositewasfirstplacedintoaslotmouldtoformabarspecimenwithrectangular-sectionof4mmmm,followedbythesurfacepaintingtocreateirregularspeckles.Curingwasthenappliedatoneendofthespecimenwhiletheotherpartwerecoveredagainstcuringlightforsimulatingtheclinicalcuringconditionofcompositeindentalcavity.Thepaintedsurfacewasrecordedbyacharge-coupleddevice(CCD)camerabeforeandaftercuring.Subsequently,thevolumetricshrinkageofthespecimenwascalculatedwithspecialistDICsoftwarebasedonimagecrosscorrelation.Inaddition,afewfactorsthatmayinfluencethemeasuringaccuracy,includingthesubsetwindowsize,specklesize,illuminationlightandspecimenlength,werealsoevaluated.Results:ThevolumetricshrinkageofthespecimengenerallydecreaseswithincreasingdistancefromtheirradiatedsurfacewithaconspicuousexceptionbeingthecompositePremiseDentineasitsmaximumshrinkageoccurredatasubsurfacedistanceofabout1mminsteadoftheirradiatedsurface.Z100hadthegreatestmaximumshrinkagestrain,followedbyZ250,TetricEvoCeramandthenPremiseDentine.Largersubsetwindowsizemadetheshrinkagestraincontoursmoother.Butthecostwasthatsomedetailsintheheterogeneityofthematerialwerelost.Verysmallsubsetwindowsizeresultedinalotofnoiseinthedata,makingitdifficulttodiscernthegeneralpatterninthestraindistribution.Speckle
简介：Ameasurementtechniquethatcanmeasuretheconcentrationofthesolidparticlesinliquidflowwasdeveloped.ThemeasurementsystemconsistsofacolorcameraandthreeLCDdisplays.ThesolidparticleswereputatthebottomofacylindricalmixingtankinwhichJetA1oilwasfilled.Transientmixingofthesolidparticleswasperformedbyrotatingapropellertypeagitatorwiththreedifferentrotationspeed(500,600,700r/min).MixingstatewasvisualizedbytheLCDdisplaysandacolorcamcorder.Thecolorintensityoftheglassparticleschangeswiththeirconcentration.ThecolorinformationwasdecodedintothreeprinciplecolorsR,G,andBsothat,thecalibrationcurveofcolor-to-concentrationwasperformedusingtheseinformation.Aneuralnetworkwasusedforthiscalibration.Thetransientconcentrationfieldofthesolidparticleswasquantitativelyvisualized.
简介：Arraygainwouldbewellexploitedtoimprovepowercoverageifsomepowerfulmultipathcomponentsfromdifferentradiolinkscancoherentlycombineatthereceiver(Rx).Thus,inthispaper,analgorithmisproposedfortransmissioninsimulcastsystem,wherepartialchannelstateinformation(CSI)isneeded.Basedonmeasuredmultipathchannel,performanceoftheproposedalgorithmisevaluated.Accordingtosimulationresults,theproposedalgorithmoutperformsthedirectionsummation(DS)schemeandmultipathantennadiversity(MAD)algorithm,with2～4dBadvantageoverthelatters.Especiallyinlineofsight(LOS)scenario,theadvantageismoreobvious.Besides,theproposedalgorithmbringsmoregainwithincreasingnumberoftransmitantennaswithoutadditionalpower.Finally,robustnessoftheproposedalgorithmisexaminedwithimperfectCSI.
简介：Aconoscopicholography-based3Dmeasurementsystemforanalyzingthedefectsonthesurfaceofsteelplateswasintroducedinthispaper.Thehardware,whichisautomatedthroughsoftware,performssamplingofthesteelplatesurface.Throughthesoftwareinterface,point-clouddataofthesteelplatesurfaceareobtainedandreconstructedtoforma3Dimageofthesteelplatesurface.Thesoftwareallowsautomaticanalysisofsteelplatesurfacedefectsthroughidentificationofthebulgesanddepressions.Inaddition,thesoftwarecanalsoautomaticallycalculatethedefectinformation,suchasthedeepestpoint,volume,openingarea,openinglength,andsoon,therebydeterminingthedefectsize.Theresultsdeterminedbythis3Dmeasurementsystemwerefoundtobeingoodagreementwiththeactualvalues.
简介：Anovelmethodofmeasuringnon-uniformstrainalongafiberBragggrating(FBG)usingopticalfrequencydomainreflectometry(OFDR)isproposedandexperimentallydemonstrated.Thismethodcanovercometheproblemsoftraditionalnon-uniformstrainmeasurementmethodsforFBGs,i.e.,thelikelihoodofchirpingandmultiplepeakinginthespectrumwhenFBGissubjectedtoinhomogeneousstrainfields.WavelengthinterrogationisrealizedbyOFDRwithanarrow-line-widthtunablelaserastheopticalsource.Whennon-uniformstraindistributionsalongareasadjacenttostructuraldamagearemeasuredbythismethod,goodagreementisobtainedbetweenmeasurementsandtheoreticalsimulationresults.
简介：Anovelphotonic-assistedapproachtomicrowavefrequencymeasurementisproposedandexperimentallydemonstrated.Theproposedschemeisbasedonthefrequency-to-powermappingwithdifferenttransmissionresponses.Apolarizerisusedinoneoutputbranchofaphasemodulatortosimultaneouslyimplementphasemodulationandintensitymodulation.OwingtothecomplementarynatureofthetransmissionresponsesandtheMach-Zehnderinterferometers(MZIs),thisschemetheoreticallyprovideshighresolutionandtunablemeasurementrange.Themeasurementerrorsintheexperimentalresultscanbekeptwithin0.2GHzoverafrequencyrangefrom0.1to5.3GHz.
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