简介：Byemployingaradiofrequency(RF)feedbackchain,theself-interferencecanbecanceledefficientlyinco-timeco-frequencyfullduplex(CCFD).However,theevitablesignalcrosstalkwhichiscausedbytheimperfectRFfeedbackchainisolationusuallydamagestheself-interferencecancelation(SIC)performance.Todealwiththisproblem,firstly,weanalyzetheimpactofRFfeedbackchainisolationonSICperformance.ThenadigitalpreprocessingschemewithRFfeedbackchainisproposedinthemultiple-antennaCCFDarchitecture.Usingbothanalyticalandexperimentalmethods,wefindthattheproposedschemeachievesabetterperformanceonSIC.

简介：Asignalwaveformrecoverymethodbasedonthecoprimearrayisinvestigatedtoextractthewaveformofthedesiredsignalfromspatialinterferencesinnarrowbandscenarios.Thedirectionofarrivals(DOAs)ofthedesiredsignalandinterferencesignalsareestimatedwiththecompressivesensingapproachbasedonanglegrids,andthesignalpowertogetherwiththenoisepowerareestimated.Thereafter,amodifiedsteepestdescent(SD)methodisderivedtorecoverthewaveformofthedesiredsignalandinterferencesutilizingtheestimatedpoweranddirections.Therecoveredwaveformofthedesiredsignalistheoutputoftheproposedmethod.Thesituationinwhichthesignalsarenotonthepredefinedanglegridsisalsoconsidered.TheDOAsestimatedpredefinedanglegridsisalsoconsidered.TheDOAsestimatedlikelihood(ML)angleestimation.Comparedtotheexistingbeamformingmethodsonco-primearray,theproposedmethodcanobtainthewaveformofthedesiredsignal.Simulationresultsdemonstratethattheproposedmethodcanachievegoodperformanceinsignalwaveformrecoveryandoutputsignaltonoiseratio.

简介：Anovelpre-ionizationschemeofhelicaltransverse-pulsedpre-ionizationinalongitudinaldischargeCO2laserispresented.Thelasertubeismadeofglasswithinnerdiameterof7.5mmanddischargelengthof50cm.Thelaserperformancecharacteristicsasfunctionsofparameters,suchaspressure,chargingcapacitanceandappliedvoltage,areinvestigated.Comparedwiththesamelaserstructurewithoutpre-ionization,themaximumpulseenergyimprovesby23%,theoptimumelectro-opticalefficiencyincreasesby31%,andthespecificoutputenergyreaches26J/(L·atm).

简介：Cu-andCo-substitutedNiZnferritethinfilms,Ni0.4-xZn0.6CuxFe2O4andNi0.5Zn0.5CoxFe2-xO4(0≤x≤0.2),aresynthesizedbysol-gelprocess.ThecrystallographicandmagneticpropertiesofCu-andCo-substitutedNiZnferritethinfilmshavebeeninvestigated.ThelatticeparameterdecreaseswithCusubstitutionandincreaseswithCosubstitution.ThesaturationmagnetizationdecreasesandthecoercivityincreaseswiththeincreaseofCusubstitution.Moreover,thesaturationmagnetizationgraduallyincreaseswiththeincreaseofCosubstitutionwhenx≤0.10,butdecreaseswhenx>0.10.Meanwhile,thecoercivityinitiallydecreaseswiththeincreaseofCosubstitutionwhenx≤0.10,butincreaseswhenx>0.10.

简介：Inthispaper,quartzcrystalmicrobalance(QCM)gassensorscoatedwithpolyehtyleneimine(PEI)wasutilizedforcarbondioxide(CO2)detection.Thesensingmechanismisbasedontheavailabilityofreversibleacid-basereactionsbetweenCO2moleculesandPEIatroomtemperature.TheexperimentalresultsrevealedthatthePEI/starchsensorexhibitedmuchhighersensitivitythanthatofpurePEI,andshowedapproximatelinearityoveraconcentrationregionrangingfrom500ppmto8000ppm.Theinfluenceofhumidityhadalsobeeninvestigated.Furthermore,theresponseandrecoverytimedeceasedastheoperationtemperaturesincreased.Finally,sensitivitylossafterconservationforseveraldaysandreversibilityofthesensorshadbeendiscussed.

简介：Dispersionandnonlineardistortionhaveaneffectontransmissionperformancesofopticalfibertransimissionsystems,Theschemesofdispersioncompensationandnonlineardistortionself-compensationintelecom-CATVco-networktransmissionsystemsarereported,followedbyinvestigationon(1)theimpactofdispersioncompensationfiber(DCF)onfibernonlineareffectswithacascadeoferbium-dopedfiberamplifiers(EDFAs)anddifferentdispersioncompensationschemes,(2)theimpactofthecomplexonthetotalnonlineardistortioninducedbyEDFAgaintiltandthelightsource.Asaresult,dispersioncompensationoptimalschemeandEDFAnegativegaintiltaresuggestedasasolutiontodispersioncompensationoptimalschemeandEDFAnegativegaintiltaresuggestedasasolutiontodispersioncompensationandthenonlineardistortionself-compensation.

简介：Aimingattheproblemofthepeaktoaveragepowerratio（PAPR）incoherentopticalorthogonalfrequencydivisionmultiplexing（CO-OFDM）,ahybridPAPRreductiontechniqueoftheCO-OFDMsystembycombiningiterativepartialtransmitsequence（IPTS）schemewithmodifiedclippingandfiltering（MCF）isproposed.Thesimulationresultsshowthatatthecomplementarycumulativedistributionfunction（CCDF）of104,thePAPRofproposedschemeisoptimizedby1.86dBand2.13dBcomparedwiththoseofIPTSandCFschemes,respectively.Meanwhile,whenthebiterrorrate（BER）is10^-3,theopticalsignaltonoiseratio（OSNR）areoptimizedby1.57dBand0.66dBcomparedwiththoseofCFandIPTS-CFschemes,respectively.

简介：ThemicrostructureandopticalpropertiesofaburiedlayerformedbyO+(200keV,1.8×1018/cm2)andN+(180keV,4×1017/cm2)co-implantationandannealedat1200℃for2hhavebeeninvestigatedbyAugerelectron,IRabsorptionandreflectionspectroscopicmeasurements.TheresultsshowthattheburiedlayerconsistsofsilicondioxideandSiOx（x<2）andthenitrogensegregatestothewingsoftheburiedlayerwhereitformsanoxynitride.BydetailtheoreticalanalysisandcomputersimulationoftheIRreflectioninterferencespectrum,therefractiveindexprofilesoftheburiedlayerwereobtained.

简介：Aco-designschemeofevent-triggeredsamplingmechanismandactivefaulttolerantcontrol(FTC)isdeveloped.Firstly,afaultdiagnosisobserverisdesignedtoestimateboththefaultandthestatesimultaneouslybyusingtheevent-triggeredsampledoutput.SomeH∞constraintsbetweentheestimationerrorsandtheevent-triggeredsamplingmechanismareestablishedtoensuretheestimationaccuracy.Then,basedontheconstraintsandtheobtainedfaultinformation,anevent-triggereddetectorandastaticfaulttolerantcontrollerareco-designedtoguaranteethestabilityofthefaultysystemandtoreducethesensorcommunicationcost.Furthermore,theproblemoftheeventdetectoranddynamicFTCco-designisalsoinvestigated.Simulationresultsofanunstablebatchreactorarefinallyprovidedtoillustratetheeffectivenessoftheproposedmethod.

简介：Classifyingthetextureofgranulesin2Dimageshasarousedmanifoldresearchatten-tionforitstechnicalchallengesinimageprocessingareas.ThisletterpresentsanaggregatetextureidentificationapproachbyjointlyusingGrayLevelCo-occurrenceProbability(GLCP)andBPneuralnetworktechniques.First,upto8GLCP-associatedtexturefeatureparametersaredefinedandcomputed,andtheseconsequentparametersnextserveastheinputsfeedingtotheBPneuralnetworktocalculatethesimilaritytoanyofgivenaggregatetexturetype.Afinitenumberofaggregateimagesof3kinds,witheachcontainingspecifictypeofmineralparticles,areputtotheidentificationtest,experimentallyprovingthefeasibilityandrobustnessoftheproposedmethod.

简介：所有纤维基于Er~(3+)：Yb~(3+)共同做在1550nm操作的两倍穿着的光纤激光器被表明。由使用9m渴望Er~(3+)：Yb~(3+)共同做纤维(EYDF)著名计算机生产厂商他获得媒介，并且当波长过滤，用一双纤维布拉格栅栏，产量激光的线宽象0一样狭窄。2nm和产量力量是超过6mW。在它的排放前的激光的荧光灯的效果也被学习。并且它被发现Er~(3+)：Yb~(3+)共同做双clad光纤激光器也在1080nm附近为Yb~(3+)转变展出高获得。

简介：borophosphate眼镜的作文上的白光的颜色点的依赖与铕(Eu)和铽(Tb)共同做以稀土元素离子的原子价变化被调查了。在下面紫外(紫外)刺激，白光被观察从在为Eu2+的425nm的4f65d4f7乐队转变排放的联合，5D07FJ(J=1，2)在593nm的线排放和为Eu3+的611nm，并且在为Tb3+的545nm的5D47F5乐队转变排放。由改变玻璃作文，结果的排放颜色能高效地被调节。最后，有委员会的优化的白光国际deIEclairage(CIE)坐标(0.3382，0.2763)并且在5010K的相互关联颜色温度(CCT)被完成。

简介：Inthispaper,awavelengthdivisionmultiplexing(WDM)transmissionsystemderivedfromthecoherentopticalorthogonalfrequencydivisionmultiplexing(CO-OFDM)withpolarizationdivisionmultiplexing(PDM)and16-orderquadratureamplitudemodulation(QAM)isstudied.Asimulationof80-channelWDMtransmissionsystemwithdatarateof200Gbit/sisbuilt,andthetransmissionperformanceofthesystemisanalyzed.ThesimulationresultsshowthatthesystemQvalueoftheWDMchannelsat16Tbit/swithaspectralefficiencyof7.14bit/s/Hzispotentiallyover10.0dBforalonghaultransmissionupto1800kminastandardsingle-modefiber.

简介：AnewS-typeoferbium-ytterbiumco-dopedphosphateglasswaveguideamplifierintegratedwithcascadedmultilayermediumthinfilmfilterisproposed,thisS-typegeometrywaveguidestructureisusedtoachievealongpathinacompactchip,andobtainedhighergainwithlowerEr-dopedconcentration.Thecascadedmultilayermediumthinfilmfilterisutilizedtoachieveabroaderflatteninggainbandwidth.Theintrinsicalgainspectrumisobtainedbysolvingrateandpowerpropagationequations,theeffectoftransmittancespectrumofthinfilmfilteronflatteninggainisdiscussed.