简介:Thispaperinvestigatesthetemperaturefielddistributionandthermalfocallengthwithinalaserdiodearray(LDA)end-pumpedYVO4/Nd:YVO4rectangularcompositecrystal.AgeneralexpressionofthetemperaturefielddistributionwithintheNd:YVO4rectangularcrystalwasobtainedbyanalysingthecharacteristicsoftheNd:YVO4crystalandsolvingthePoissonequationwithboundaryconditions.ThetemperaturefielddistributionsintheNd:YVO4rectangularcrystalfortheYVO4/Nd:YVO4compositecrystalandtheNd:YVO4singlecrystalareresearchedrespec-tively.CalculatingthethermalfocallengthwithintheNd:YVO4rectangularcrystalwasdonebyananalysisoftheadditionalopticalpathdifferences(OPD)causedbyheat,whichwasveryidenticalwithexperimentalresultsinthispaper.ResearchresultsshowthatthemaximumrelativetemperatureontherearfaceoftheNd:YVO4crystalinthecompositecrystalis150Kandthethermalfocallengthis35.7mmwhentheoutputpoweroftheLDAis22W.Inthesamecircumstances,theexperimentalvalueofthethermalfocallengthis37.4mm.Sotherelativeerrorbetweenthetheoreticalanalysisandtheexperimentalresultisonly4.5%.Withthesameconditions,thethermalfocallengthoftheNd:YVO4singlecrystalis18.5mm.SotherelativerateofthethermalfocallengthbetweentheYVO4/Nd:YVO4crystalandtheNd:YVO4crystalis93%.So,thethermalstabilityoftheoutputpowerandthebeamqualityoftheYVO4/Nd:YVO4laserismoreadvantageousthanthelaserwithNd:YVO4singlecrystal.
简介:AKerr-lens,mode-lockedYVO4∕Nd:YVO4lasercoupledwithanacousto-opticmodulator(AOM)Q-switchingnear1064nmwasemployedtopumpanintracavityKTiOPO4(KTP)opticalparametricoscillator.Asubnanosecondsignalwavenear1572nmwithlowrepetitionratewasrealized.AtanAOMrepetitionrateof8kHz,themaximumoutputpowerwas165mW.Thehighestaveragepulseenergy,theshortestduration,andthehighestpeakpowerofamode-lockingsignalpulsewereestimatedtobe~10.3μJ,~120ps,and~82kW,respectively.
简介:Inthispaper,weproposealocalfuzzymethodbasedontheideaof"p-strong"communitytodetectthedisjointandoverlappingcommunitiesinnetworks.Inthemethod,arefinedagglomerationruleisdesignedforagglomeratingnodesintolocalcommunities,andtheoverlappingnodesaredetectedbasedontheideaofmakingeachcommunitystrong.Weproposeacontributioncoefficientbvcitomeasurethecontributionofanoverlappingnodetoeachofitsbelongingcommunities,andthefuzzycoefficientsoftheoverlappingnodecanbeobtainedbynormalizingthebvcitoallitsbelongingcommunities.Therunningtimeofourmethodisanalyzedandvarieslinearlywithnetworksize.Weinvestigateourmethodonthecomputergeneratednetworksandrealnetworks.Thetestingresultsindicatethattheaccuracyofourmethodindetectingdisjointcommunitiesishigherthanthoseoftheexistinglocalmethodsandourmethodisefficientfordetectingtheoverlappingnodeswithfuzzycoefficients.Furthermore,thelocaloptimizingschemeusedinourmethodallowsustopartlysolvetheresolutionproblemoftheglobalmodularity.
简介:Themagnetoresistanceeffectofap–njunctionunderanelectricfieldwhichisintroducedbythegatevoltageatroomtemperatureisinvestigatedbysimulation.Asauxiliarymodels,theLombardiCVTmodelandcarriergenerationrecombinationmodelareintroducedintoadrift-diffusiontransportmodelandcarriercontinuityequations.Alltheequationsarediscretizedbythefinite-differencemethodandtheboxintegrationmethodandthensolvedbyNewtoniteration.Takingadvantageofthosemodelsandmethods,anabruptjunctionwithuniformdopingisstudiedsystematically,andthemagnetoresistanceasafunctionofdopingconcentration,SiO_2thicknessandgeometricalsizeisalsoinvestigated.Thesimulationresultsshowthatthemagnetoresistance(MR)canbecontrolledsubstantiallybythegateandisdependentonthepolarityofthemagneticfield.
简介:Electromechanicalpropertyofap-typesingle-crystalsiliconnanoplateismodelledbyamicroscopicapproachwheretheholequantizationeffectandthespin-orbitcouplingeffectaretakenintoaccount.Thevisibleanisotropicsubbandstructuresarecalculatedbysolvingself-consistentlythestress-dependent6×6k·pSchrdingerequationwiththePoissonequation.Thestrongmixingamongheavy,light,andsplit-offholesisquantitativelyassessed.Theinfluencesofthethicknessandthetemperatureonthepiezoresistivecoefficientarequantitativelyinvestigatedbyusingtheholeconcentrationsandtheeffectivemassesfromthecomplexdispersionstructureofthevalencebandwithandwithoutstresses.Ourresultsshowthatthestressdeterminestheextenttowhichthebandismixed.Theholequantizationeffectincreasesasthethicknessdecreases,andthereforethevalencebandisstronglyreshaped,resultinginthesize-dependentpiezoresistivityofthesiliconnanoplate.Thepiezoresistivecoefficientincreasesalmost4timesasthethicknessreducesfromthebulkto3nm,exhibitingapromisingapplicationinmechanicalsensors.
简介:Geant4LowEnergyElectromagneticpackageProvidesaprecisetreatmentofelectromagneticinterationsofparticleswithmatterdowntoverylowenergies(250oVforelectronsandphotons,<1keVforhadronsandions),Itincludesaverietyofmodelsfortheelectromagneticprocessesofelectrons,photons,hadronsandions,takingintoaccountadvancefeatures,suchasshelleffectsandeffectsduetochargedependence.Thecomprehensivesetofparticletypesitcanhandle,thevarietyofmodelingapproachesandtheextendedcoverageofenergyrangemakethispackageauniquetoolamongMonteCarlocodesonthemarket,andofrelevancetoserveralexperimentaldomainsinHIEP,astroparticlephysics,spacescienceandbiomedicalstudies.
简介:PD(X3?)相互作用潜力用CCSD(T)理论和基础集合被构造,aug-cc-pV5Z。用这个潜力,分光镜的参数是精确地坚定的。礼品,De,Re,e,ee,e,并且具有3.05699eV,3.16175eV,0.14239nm,1701.558厘米?1,23.6583厘米?1,0.08599厘米?1,和4.3963厘米?1,分别地它几乎完美地符合大小。当时,26个震动的状态的一个总数被预言J=0由解决光线的Schr?原子运动的dinger方程。完全的震动的层次,古典拐弯处点,起始的旋转和离心的失真常数什么时候J=0第一次被报导,它有利地同意实验。全部、各种各样的部分波浪的生气的节在1.0魄为在二个地面状态P和D原子之间的有弹性的影响被计算吗??
简介:目的:研究P波斜入射下的地基动应力路径,探讨其影响因素和可能变化范围,为进一步研究斜入射地震波作用下场地动力响应奠定理论基础。创新点:1.从数学上证明斜入射P波在任一深度的地基中形成的应力路径在剪应力分量(偏差正应力-水平剪应力)组成的平面中为一个斜椭圆;2.分析了P波入射角、土体泊松比和单位波长深度对斜椭圆应力路径形状与大小的影响。方法:1.基于半无限弹性空间的地震波传播理论,考虑地震波在自由界面的反射,推导土体中任一深度处由P波斜入射产生的动应力,并表示成由剪应力分量组成的平面下的应力路径(公式(9))及该应力路径的特征参数表达式(公式(A12)~(A14));2.通过控制变量法,分析参数敏感性(图7、9、10和12)。结论:1.虽然证实P波斜入射引起的应力路径为斜椭圆形式,但在地基深度、入射波频率和波速的特定组合下,斜椭圆仍可从斜线一直变化到圆形,形式较为多样化;2.P波斜入射角度在30?~60?时引起的动偏应力幅最大,最大可达同等条件下其它入射角产生的动应力幅的2倍以上;3.斜入射角大于45?后,斜椭圆路径形状几乎不随入射角改变,在研究范围内以竖直扁椭圆形为主;4.土体饱和度大于70%时,泊松比的变化对土体斜椭圆路径形状影响不大,但动应力幅随泊松比增大而显著降低。