简介:Anovelrepetitivecontrolstrategyfortheoutputwaveformofsingle-phaseCVCFinvertersispresented.Inthisscheme,theinversetransferfunctionofinverterisusedasacompensatortoobtainstableandsatisfyharmonicrejection.Besides,PDcontrollerisadoptedtoimprovetransientperformance.Simulationandexperimentalresults,whicharegottenfromaDSP-based400Hz,5.5KWinverter,indicatethattheproposedcontrolschemecanachievenotonlylowTHDduringsteady-stateoperationbutalsofasttransientresponseduringloadstepchange.
简介:Abinaural-loudness-model-basedmethodforevaluatingthespatialdiscriminationthresholdofmagnitudesofhead-relatedtransferfunction(HRTF)isproposed.Astheinputofthebinauralloudnessmodel,theHRTFmagnitudevariationscausedbyspatialpositionvariationswerefirstlycalculatedfromahigh-resolutionHRTFdataset.Then,threeperceptualrelevantparameters,namelyinterauralloudnessleveldifference,binauralloudnesslevelspectra,andtotalbinauralloudnesslevel,werederivedfromthebinauralloudnessmodel.Finally,thespatialdiscriminationthresholdsofHRTFmagnitudewereevaluatedaccordingtojust-noticedifferenceoftheabove-mentionedperceptual-relevantparameters.AseriesofpsychoacousticexperimentswasalsoconductedtoobtainthespatialdiscriminationthresholdofHRTFmagnitudes.Resultsindicatethatthethresholdderivedfromtheproposedbinaural-loudness-modelbasedmethodisconsistentwiththatobtainedfromthetraditionalpsychoacousticexperiment,validatingtheeffectivenessoftheproposedmethod.
简介:Undertheconditionofhigh-powerdrive,theexperimentalphenomenaoffreestatoroftravelingwaveultrasonicmotortakesonstrongnonlineareffects.Firstly,itscorrespondingtheoriesareestablishedtoanalyzeandcomparethestator'sperformancesattheresonanceandantiresonancestates.Atthesametime,someimportantparameters,suchasresonance/antiresonancefrequency,mechanicalquality,electro-mechaniccoupling,andtherelativevibrationeffect,areselectedelaboratelytoevaluatethevibrationalperformancesoffreestator.Then,someexperimentalschemesbasedonthelaservibrationmeasurementaredesignedrespectively.Underthedifferentdrivesconditions,theexperimentalcharacterizationsoffreestatorattheresonanceandantiresonancestatesareanalyzedsystematically.Finally,Theinvestigativeresultsshowthattheperformanceattheantiresonancestateismuchbetterthanthatattheresonancestate.Someconclusionsofthispapercanprovidenovelideaandguidanceforthechoosingoftheoperatingstatesanddrivingmodesoftravelingwaveultrasonicmotor.
简介:Distortion-freedataembeddingisatechniquewhichcanassurethatnotonlythesecretdataiscorrectlyextractedbutalsothecovermediaisrecoveredwithoutanydistortionaftersecretdataisextractedcompletely.Becauseoftheseadvantages,thistechniqueattractstheattentionofmanyresearchers.Inthispaper,anewdistortion-freedataembeddingschemeforhighdynamicrange(HDR)imagesisproposed.BydependingonCartesianproduct,thisschemecanobtainhigherembeddingcapacitywhilemaintainingtheexactlyidenticalcoverimageandstegoimagewhenusingthetonemappingalgorithms.Inexperimentalresults,theproposedschemeissuperiortoYuetal.'sschemeinregardtotheembeddingrate?anaverageembeddingrateof0.1355bppcomparedwithYuetal.'sscheme(0.1270bpp).
简介:无
简介:Thedynamiccharacteristicsofthelargescalecoherentstructuresinaforcedfreeshearlayerareexperi-mentallystudiedbymeansofflowvisualization.ThequantitativemeasurementsareacquiredbytheuseofaLDV.Itisshownthatthedevelopmentofthecoherentstructurescanbegreatlyinfluencedbyupstreamartificialperturbationsandasaresultthemixinginthelayercanbecontrolled.Likevortexmerging,vortexsplittingisalsoacommonevolu-tionpatterninthedevelopmentofthecoherentstructures.
简介:没有羡慕的定价问题能作为发现每个消费者在被分配的一个定价和分配计划在定价下面最大化其用途的一套项目被说。目标是最大化卖主收入。我们与作为在项目上定义的一个独立系统被给的一般供应限制学习这个问题。例如,限制能是很多线性限制或matroids。这捕获项目不在资源的限制下面在项目的消费者估价的思考先存在,但是被生产的状况。这份报纸集中于单位要求消费者的盒子。在背景,有n消费者和m项目;每个项目可以在多重拷贝被生产。每消费者i[n]在他/她感兴趣的集合S对i在条款j上有估价vij。他/她必须被分配(如果任何)给最大值的一个项目(非否定)用途。假定我们为发现最大的重量独立人士为给定的独立系统设定被给近似神谕(或稍微更强壮的神谕);为很多自然、有趣的供应限制,经常的近似算法是可得到的。我们获得下列结果。1)O(木头n)为一般盒子的近似。2)O(k)近似每个消费者什么时候至多对感兴趣k项目的不同类型。3)O(f)近似条款的每种类型什么时候至多对有趣f消费者。笔记期末考试甚至没有独立系统限制,二结果以前是未知的。
简介:AccordingtoXinhuaNet,startingfrom2011,InnerMongoliaAutonomousRegionwillprovidefreeeducationandtextbookstoallthestudentsstudyingingeneralMongoliansecondaryschoolsandsecondaryvocationalschools,andfinanciallydisadvantagedstudentswhoarelearningingeneralChinesesecondaryschools.By2013,thepracticeswillcoverallsecondaryschoolstudentsinalldistricts,sofreeeducationfor
简介:Fluorineinmoldpowderisknownasharmfultohumanhealthandtheenvironment.Beingtheadvocateofgreenproduction,Baosteeldevelopedanenvironmentallyfriendlymoldpowderwithoutfluorine.Themainproblemoffluorine-freefluxfilmissmallheatresistanceandthustheheattransferintensityofthemoldistoolarge,whichtosomeextenthinderstheincreaseofthecastingspeed.Withtheheatflowsimulationequipment,controllingprecipitationofcrystalinfluxandsolidificationtemperatureproperly,fluorine-freemoldpowderforlowcarbonsteel,whichsubstitutesFwithB2O3,wassuccessfullydevelopedandappliedinindustrialproduction.Theproductionresultsshowthat,byusingboronicfluorine-freemoldpowder,theboronincrementinmoltensteelislessthan1.3ppmforconventionalaluminiumkilledlowcarbonsteel.
简介:ThispaperprovidesareviewonsampleinjectorswhichareprovidedatSPring-8AngstromCompactfreeelectronLAser(SACLA)forconductingserialmeasurementina‘diffract-before-destroy'schemeusinganx-rayfreeelectronlaser(XFEL).VersatileexperimentalplatformsatSACLAareabletoacceptvarioustypesofinjectors,amongwhichliquidjet,dropletandviscouscarrierinjectorsarefrequentlyutilized.Theseinjectorsproducedifferentformsoffluidtargetssuchasaliquidfilamentwithadiameterintheorderofmicrometer,micro-dropletsynchronizedtoXFELpulses,andslowlyflowingcolumnofhighlyviscousfluidwitharatebelow1μLmin-1.Characteristicsandapplicationsoftheinjectorsaredescribed.
简介:ThispaperdealswiththeapproximatesolutionoftheFredholmequationLu=fofthesecondkindwithf∈H’(Γ).First,wegivetheorderofthen-theoptimalradiusintheworstcasesetting.Then,weshowthattheGalerkinmethodusing2n+1innerproductsoffhasminimalerror.Finally,wegivetheestimateoftheε-complexityoftheFredholmproblemofthesecondkindandGalerkinmethodintheworstcasesetting.
简介:Araucariaangustifolia(Bertol.)O.Kuntzeexhibitsdimorphisminitsstemstructure,wherethetrunkisorthotropicandbranchesandbranchlets(primaryandsecondarybranches)areplagiotropic.Thesestemsexhibitdifferentbehaviorwhenusedforvegetativepropagation,andonlysegmentsoftrunkcanformacompleteplant.Thephysiologicalandbiochemicalmechanismsthatcharacterizethesestemsarestilllittleknown.Theaimofthisstudywastodescribethefreeaminoacidprofilesintrunks,branches,andbranchletsofA.angustifolia.Segmentsof5cminlengthwereexcisedfromyoungindividualsbelowthestemapex.Theneedleswereremovedandsampleswerefrozenandlyophilized.Thedeterminationsweremadebyhigh-performanceliquidchromatography,andtheresultswereexpressedaslg/gfreshweight(FW).Thetrunksandbrancheshadthehighestcontentoftotalaminoacids,whichwere112.23±20.57lg/gFWand111.97±27.78lg/gFW,respectively.Theaminoacids—glutamine,aspartateandc-aminobutyricacidandtyrosine—werenoticeablyhigherinthethreetypesofstems.Inthetrunk,ahigheramountofasparagineandtryptophan,wasalsodetected.Glutamicacidandglutaminewerefoundinhigherquantitiesinthebranches.Thebranchletshadverylowtotalaminoacidcontent(30.79±4.19lg/gFW),whereinasparagineistheonlyaminoacidnotdetected.Thus,itwasobservedthattheprofileofthefreeaminoaciddiffersamongtrunks,branches,andbranchletsinA.angustifolia,indicatingthattheyperformdifferentfunctions.
简介:免费生活的海洋的线虫的五种是redescribed并且在中国的黄海说明同样新的记录。这些种类包括一monhysterid,在家庭Diplopeltidae的Campylaimusgerlachi和四enoplids在家庭Oxystominidae的种类,Oxystominaelongata,Oxystominaelegans,Halalaimuslutarus和Halalaimuswodjanizkii。生态、分类的讲话与原来的描述比较被提供并且讨论。类Campylaimus的所有已知的种的关键被给。我们的调查结果离开犯错到benthic生态学和生物多样性的线虫的分类信息黄海学习。
简介:Financialcrisis-thedrivetointegrationofregionaleconomiesTwosalientfeaturesareillustratedintoday'sglobaleconomypattern,whichis,economicglobalizationandtheintegrationofregionaleconomies.Theintegrationofregionaleconomiesstimulatestheglobalization,whileontheotherhandintegratingcountriesthataregeographicallycloseaimstofightagainstthenegativeimpactfromglobalization,includingthefinancialcrisis.
简介:Inholographicencryption,doublerandom-phaseencodingintheFresneldomain(DRPEiFD)isaprevalentencryptionmethodbecauseitislenslessandsecure.However,noisesbringadverseeffectsduringdecryption.Inthisletter,weintroducequick-response(QR)codingduringencryptiontoresistnoises.WetransformtheoriginalinformationintoaQRcodeandthenencryptthecodeasahologramthroughDRPEiFD.Toretrievetheinput,wedecryptthehologramintheoppositemannertotheencryptionandsubsequentlyobtainaQRcodewithnoises.Byscanningthiscodewithproperapplicationsinsmartphones,wecanobtainanoise-freeretrieval.Numericalexperimentsandimagesscannedbyasmartphoneareshowntovalidateourproposedmethod.