简介:Therecursivestructureandquasi-recursivestructureofAdaptiveVolterraFil-ter(AVF)areputforward,theiralgorithmsaregiven,andtheircharacteristicsandapplicationsarediscussed.TheintroductionofrecursivestructurecanremarkablyreducetheparametersandcomputationalcostofAVF.
简介:TheenvironmentofthepostalindustryinChinahasexperiencedtremendouschangesinthepastfewyears.TheenvironmentalchangeshavesomeeffectsontheelementsthatdecidetheservicestructureofChinaPost.Insuchcontext,thecurrentservicestructureofChinaPostneedssomeimprovementstoadaptitselftothechangingenvironment.AimingattheoptimizationoftheservicestructureofChinaPost,thispaperreviewsthelawofitsdevelopmentandmakesananalysisofitscurrentcharacteristicsandtheexistingproblems.
简介:Anewall-opticaldemultiplexerbasedonnonlineareffectinsemiconductorlaseramplifier(SLA)isproposed.ItcandemultiplexallchannelsoftheOTDMsignalconcurrently.anditcanalsobeintegratedonasinglechip.TheproposeddeviceconsistsofaseriesshortFabry-Perotamplifiers(FPSLA)settingonthepathverticsally,throughwhichthepreamplifiedopticalsignaltravels.Perpendicularlytothesignal,K(channelnumber)paralleledbeamsoflightpulse,whichactasprobeswithrepetitionatthebitrateofonechannel,irradiateontheseFP-SLAs,respectively,justwhenthecorrespondingsignalchannelpulsepassesthroughtheactiveregionfromlateralside.Thetransmissivitydependsonthesignalpulse.Theoreticalanalysishasbeengiven.Asademonstratingexample,Adeviceoperatedatthespeedof25Gbit/s(2.5Gbit/s×10)issimulatedandtheresultsshowthattheabout9.24dBextinctionratiocanbeachievedeasily.
简介:Theelectroluminescencethinfilmsdopedwitherbium,fabricatedbythermalevaporationwithtwoboats,areanalyzedbyX-raydiffraction(XRD).Therelationshipbetweenelectroluminescencebrightnessandmicrostructureofthethinfilmsisobtained.Theresultsrevealthatthelargegrainsizeinhighindexplaneofdepositedmicrocrystallinefilmhasaneffectonelectroluminescencecharacteristicsofthefilmdevices.
简介:Theγ-rayradiationwillspeedupthedischargeofthestoredchargeinnonvolatileMNOSstructure.Theradiationabsorptionmechanismtoenhancethedischargeisdiscussed.Adirectradiationemissionmodelfromtheinterfacetrapsdistributingbothinenergylevelandinspaceisgiven.Thetheoreticalresultsbasedonthismodelareingoodagreementwithexperimentalmeasurement.
简介:Toimprovedatacacheperformance,optimizingprogramdatalayoutbydatareorganizationhasbecomeanimportantmethodofdecreasingtheimpactofincreasinggapofspeedbetweenprocessorandmemory.Inthisarticle,astructuresplittingframeworkwithananalysismodelnamedstructurefieldrelationgraph(SFRG)ispresentedtooptimizeprogramdatalayout.TheSFRGcanbeusedtoquantifyrelationshipbetweenfields.Ithelpstofindanoptimallayoutforstructureaswellastheoptimalprogramdatalayout.AndthedatacacheperformanceisimprovedthroughSFRG-basedstructuresplitting.Experimentsshowthatthisframeworkiseffectiveinoptimizingprogramdatalayoutandimprovingtheperformanceofdatacacheandwholeprogram.
简介:TheservicestructureofChinapostisnotmatchthepostalresourcesstructure,Coreserviceisnotstressed.Therefore,thepostalservicemustbereorganizedandAdjustedaccordingtothemarketneeds.Thisarticleclassifypostserviceintofivecatalogues,proposesthestrategicorientationofeachcataloguesandanalysestheinteriorstructureofdifferentpostalservice.
简介:这份报纸试图介绍一种交互颜色自然图象分割方法。这个方法由使用非线性的紧缩的结构张肌(NCST)然后使用GrabCut方法获得分割提取图象的特征。这个方法不仅认识到质地信息和颜色信息的非参量的熔化,而且改进计算的效率。然后,改进GrabCut算法被用来评估前景目标分割。以便计算简洁和效率,这份报纸也扩大构造的Gaussian混合模型(GMM)到张肌空间的GrabCut上的底,和使用Kullback-Leibler(KL)分叉而不是平常的Riemannian几何学。最后,一个重复集中标准被建议与满足的分割精确性戏剧性地减少GrabCut算法的重复的时间。在在合成质地图象和自然图象上进行很多实验以后,结果证明这个方法有更精确的分割效果。
简介:Thispaperanalyzesthepossibilitytodiscriminatebetweenconvectiveprecipitationandstratiformprecipitation.Thisstudyaimstoimprovethemeasurementofrainfallfromteledetectiondataobtainedbothonthegroundandinspace.Forthis,twoparameters,fractaldimensionandfractallacunarity,areconsidered.Tocalculatethefractaldimension,weusetheapproachofbox-countingandshowthatthefractaldimensiondiffersbetweenconvectivescellsandstratiformsones.Andthenthefractallacunarityparameteriscalculatedbyusingtheslidingboxesalgorithm.Thestudyforalltheregionsshowsthatprecipitationcellscanbedescribedbydifferentlacunaritieswhateverthescaleofanalysis.Wededucethatthetwoparameters,fractaldimensionandfractallacunarity,canbeusedtoclassifyprecipitationsinconvectiveregimeandstratiformregime.
简介:Anovelmethodfordesigningabeam-switchingantennawiththeplanedipoleispresented.Theantennaiscomposedofdoubledipolesplacedatthecenterofanactivesquarestructurethatisdividedinfourequalsectorsbymetallicsheets.Metallicpatchesattheoutsideofthestructureareusedtoenhancetheradiationperformanceoftheantenna.Ineachstep,thediodesinonesectorareon,whereasotherdiodesareoff.Thesectorwithoff-statediodesdefinesthedirectionoftheradiationpattern.AnantennamodelisdesignedonthesubstrateofFR4.Theproposedantennaoperatesfrom4.8GHzto5.5GHzwithgainof6.3dBiandF/B(fronttobackratio)of13.2dBiwhentheoperatingfrequencyis5.2GHz.Theantennaradiationpatterncanbesweptintheentireazimuthplaneinfourstepswitha3dBbeamwidthof90.Theresultsrevealthattheantennacouldbeusedinthebasestationofthewirelesscommunicationsystems.
简介:聚合Mach-Zehnder肋骨波导的系统的分析基于计算和优化被介绍。模拟与有效索引方法(EIM)被执行并且二维(2-D)有限差别横梁繁殖方法(FD-BPM)。在连续聚合物层之间的大折射索引步被使用EIM减少,因此,计算的精确被保证。象Y连接角度和分离差距那样的波导的重要参数被讨论,他们与光力量繁殖和损失特征的关系在这篇论文被调查。优化结构的全部的损失是0.258dB。CLC数字TN252这个工程被基础为武器设备的进展研究节目支持,中国(资助No.02040105DZ02)。
简介:Anovelmethodfordesigningabeam-switchingantennawiththeplanedipoleispresented.Theantennaiscomposedofdoubledipolesplacedatthecenterofanactivesquarestructurethatisdividedinfourequalsectorsbymetallicsheets.Metallicpatchesattheoutsideofthestructureareusedtoenhancetheradiationperformanceoftheantenna.Ineachstep,thediodesinonesectorareon,whereasotherdiodesareoff.Thesectorwithoff-statediodesdefinesthedirectionoftheradiationpattern.AnantennamodelisdesignedonthesubstrateofFR4.Theproposedantennaoperatesfrom4.8GHzto5.5GHzwithgainof6.3dBiandF/B(fronttobackratio)of13.2dBiwhentheoperatingfrequencyis5.2GHz.Theantennaradiationpatterncanbesweptintheentireazimuthplaneinfourstepswitha3dBbeamwidthof90.Theresultsrevealthattheantennacouldbeusedinthebasestationofthewirelesscommunicationsystems.
简介:Superlatticesconsistingofalternatinglayersoforganic/polymericmaterialshavebeenfabricatedfromtris(8-hydroxyquinoline)aluminum(Alq3)andpoly(N-vinylcarbazole)(PVK)byamultisource-typehigh-vacuumorganicmoleculardeposition.ThecharacteristicsofsuperlatticestructuresaredeterminedbythesmallangleX-raydiffraction,opticaladsorptionandphotoluminescence.Theelectroluminescentdeviceswiththesuperlatticestructurehavealsobeenfabricatedandtheemissioncharacteristicsarediscussed.
简介:Anovelcompactelectromagneticbandgap(EBG)structureconstructedbyetchingtworeversesplitrings(RSRs)andinsertinginterleavingedge(IE)onthepatchofconventionalmushroom-likeEBG(CML-EBG)isinvestigated.SimulateddispersiondiagramsshowthattheproposedEBGstructurepresentsa13.6%sizereductioninthecenterfrequencyofthebandgap.TwocomparisonshavebeencarriedoutfortheanalysisoftheeffectoftheRSRsandIEconfiguration.Then,asampleofthisnovelEBGisfabricatedandtested,furtherexperimentaldataagreewellwiththesimulatedresults.Thus,thisEBGstructuremakesagoodcandidatetodecreasemutualcouplingincompactmicrostrippatcharray.
简介:OrderingbasedsearchmethodshaveadvantagesovergraphbasedsearchmethodsforstructurelearningofBayesiannetworksintermsontheefficiency.Withtheaimoffurtherincreasingtheaccuracyoforderingbasedsearchmethods,wefirstproposetoincreasethesearchspace,whichcanfacilitateescapingfromthelocaloptima.Wepresentoursearchoperatorswithmajorizations,whichareeasytoimplement.Experimentsshowthattheproposedalgorithmcanobtainsignificantlymoreaccurateresults.Withregardtotheproblemofthedecreaseonefficiencyduetotheincreaseofthesearchspace,wethenproposetoaddpathpriorsasconstraintsintotheswapprocess.Weanalyzethecoefficientwhichmayinfluencetheperformanceoftheproposedalgorithm,theexperimentsshowthattheconstraintscanenhancetheefficiencygreatly,whilehaslittleeffectontheaccuracy.Thefinalexperimentsshowthat,comparedtoothercompetitivemethods,theproposedalgorithmcanfindbettersolutionswhileholdinghighefficiencyatthesametimeonbothsyntheticandrealdatasets.
简介:Cr-dopedZnOthinfilmsarepreparedonglasssubstratesbythemagnetronsputteringtechnique.AnX-raydiffraction(XRD)isusedtoanalyzethestructuralpropertiesofthethinfilms.Itindicatesthatallthethinfilmshaveapreferentialc-axisorientation.Thepeakpositionofthe(002)planeshiftstothehigher2θvalue,andthepeakintensitydecreaseswiththeincreaseofCrdoping.Theresultsofthescanningelectronmicroscopy(SEM)showthatthesurfacemorphologybecomesloosewiththeincreaseofCrdoping.Besides,itisfoundfromthephotoluminescence(PL)measurementatroomtemperaturethattheultravioletemissionpeakandgreenemissionbandarelocatedat375nmand520nm,respectively,andbothintensitiesofthemdecreasewiththeincreaseoftheCrdopingconcentration,whilethebandgapoftheultravioletemissionshiftstothelowerwavelength.TheexperimentalresultsconfirmthattheoptimalCrdopingconcentrationis2at.%.