简介：TheshearlagtheoryisusedtoanalyzethestresstransferfromconcretematrixtoFBGsensorsbasedonthattheFBGsensorandtheconcretematrixarecomposite.Thestresstransferformulaandthecoefficientareobtained.Theexperimentsprovethatthetheoreticalresultsofthestresstransferbythestresstransferformulaareinwellagreementwiththeexperimentaldata.

简介：Theintensityandphaseformulasthatarevalidforthesaturationandinter-mediateregime(beforesaturation)arederived,andtheanalyticalexpressionswiththerationofsaturationintensitytototalincidentintensityastheirexplicitvariableareobtanied.Theintensitydepenenceofstationaryenergytransferinphotorefractiveacodirectionaltwo-wavemixingisexamined.Itisnecessarytousingtheseformulasinsomeproblems,suchasthetemperatureofintensitydependenceoftwo-wavemixing.Amethodofmeasuringexponen-tialgaincoefficientispresented,whichissuitablefortwo-wavemixinginintermediateregime.

简介：Athermalmodelofcrystalisestablished.Thetemperaturefielddifferentialequationofthediode-end-pumpedlasercrystalwithcircularcross-sectionandnewboundaryconditions,inwhichtheconvectionheattransferissupposedtoexistbetweenlasercrystalendsandair,isestablished.Theanalyticalexpressionsoftemperaturefield,thermaldistortionandadditionalopticalpathdifference(OPD)ofcrystalareobtained.Bynumericalcalculation,theinfluenceofheattransferonthethermaleffectsoflasercrystalNd:YAGisstudied.Resultsshowthatcrystal'sthermaleffects,includingtemperaturefield,thermaldistortion,OPDandthermalfocallength,areallweakenedastheheattransferthroughendsofcrystalisstrengthened.Thisconclusioncouldbeusedtocontrolthermaleffectsoflasercrystalandimprovelaserworkingstability.

简介：Theprincipleofthetwocarrierscontributingtocarrythepixelsignalchargesisfirstlypresented,andthenthebipolarjunctionphotogatetransistor(BJPT)withhighperformanceisproposedfortheCMOSimagesensor.Thenumericalanalyticalmodelofthephoto-chargetransferforthebipolarjunctionphotogateisestablishedindetail.Somenumericalsimulationsareobtainedunder0.6μmCMOSprocess,whichshowthatitsreadoutrateincreasesexponentiallywiththeincreaseofthephoto-chargeatappliedvoltage.

简介：Fibre-opticmagneticsensorswithmagnetostrictivefilmsareusedasall-fibreMach-Zehnderinterferometertodetecttheopticalphaseshift,whichiscausedbythemagnetostriction-inducedstrainstransferredfromthemsgnetostrictivefilmtothefibre.Atheoreticalmodelbasedontheplanestrainapproximationanduniformaxialstrainisdevelopedtodeterminethemagneto-mechano-opticaltransferrelationsinthiskindofsensors.Theexpressionforthemodelispresentedaswellasrelationofthephaseshiftinthefibretothemagneticandelasticpropertiesofthemagnetostrictivefilmcoatedonthefibre.Andfromthemodel,thethicknessofthefilmhassignificantinfluenceonthephaseshift.

简介：Themechanismofanon-polarizingbeamsplitter(NPBS)withasymmetricaltransfercoefficientscausingtherotationofpolarizationdirectionisexplainedinprinciple,andthemeasurementnonlinearerrorcausedbyNPBSisanalyzedbasedonJonesmatrixtheory.Theoreticalcalculationsshowthatthenonlinearerrorchangesperiodically,andtheerrorperiodandpeakvaluesincreasewiththedeviationbetweentransmissivitiesofp-polarizationands-polarizationstates.Whenthetransmissivityofp-polarizationis53%andthatofs-polarizationis48%,themaximumerrorreaches2.7nm.TheimperfectionofNPBSisoneofthemainerrorsourcesinsimultaneousphase-shiftingpolarizationinterferometer,anditsinfluencecannotbeneglectedinthenanoscaleultra-precisionmeasurement.

简介：Timesynchronizationtechniques,especiallyonthepulsepersecond(PPS)temporalbasis,haveattractedgrowingresearchinterestsinrecentyears.Inthispaper,wehaveproposedandexperimentallydemonstratedahigh-precisiontwo-waytimetransfer(TWTT)systemtorealizelong-distancedisseminationof1PPSsignalgeneratedbyahydrogenmaser.Adense-wavelength-division-multiplexing(DWDM)systemandbi-directionalerbium-dopedfiberamplifiers(Bi-EDFAs)havealsobeenadoptedtosuppresstheimpactofRayleighbackscatteringandoptimizethesignaltonoiseratio(SNR)aswell.Wehavetheoreticallyanalyzedthesystematicdelayindetail.Theultimaterootmeansquare(RMS)variationoftimesynchronizationaccuracyissub-26psandthetimedeviationcanbereducedtoaslowas1.2psat100sand0.253psat12000s,respectively.