简介:利用实赋范线性空间E上非零连续线性泛函f,确定了E上半序关系和锥Pf,证明了锥Pf的几个性质,给出了Hilbert空间中Pf的对偶锥的表现形式及由Pf确定的Hilbert投影距离与Thompson距离.
简介:捷联惯性导航系统大方位失准角的误差模型是非线性的,传统的扩展卡尔曼滤波(ExtendedKalmanFilter,EKF)会产生线性化误差,影响初始对准精度。在给出捷联惯性导航系统动基座大方位失准角误差模型的基础上,推导了粒子滤波方法(ParticleFilter,PF),并将扩展卡尔曼滤波、基于Scaled-Unscented变换的Unscented卡尔曼滤波(UnscentedKalmanfilter,UKF)和基于Residual重采样的粒子滤波用于捷联惯性导航系统的初始对准中,分别进行了加速和拐弯条件下的初始对准实验仿真。仿真结果表明,在大失准角情况下,粒子滤波相对于扩展卡尔曼滤波和Unscented卡尔曼滤波具有更高的对准精度和更快的收敛速度。
简介:AbridgearmprototypeofITERpoloidalfield(PF)convertermoduleshasbeendesignedandfabricated.Non-cophasecounterparallelconnectionischosenasthearmstructureoftheprototype.Amongallfactorsaffectingcurrentsharing,armstructureisthemainone.Duringthedesignofthearmprototype,anovelmethodbasedoninductancematrixesisemployedtoimprovethecurrentsharingofthebridgearm.Thetestresultsontheprototypeshowthatthecurrentsharingperformanceofthearmprototypeismuchbetterthanrelevantdesignrequirement,andthatthematrixmethodisveryeffectivetoanalyzeandsolvethecurrentsharingproblemsofthyristorconverters.
简介:<正>Withtherapidincreasingdemandofmetallithiumanditscompoundsinscienceandtechnology,studiesonlithiumrecoverythoughlithiumionextractionfromsaltlakebrinesarebloomingbacausemorethan60percentof
简介:Becausethelargermetallicsurroundsareheatedbytheeddycurrent,whichisgeneratedbytheACcurrentflowingthroughtheACbusbarintheInternationalThermonuclearExperimentalReactor(ITER)poloidalfield(PF)convertersystem,shieldingoftheACbusbarisrequiredtodecreasethetemperatureriseofthesurroundstosatisfythedesignrequirement.ThreespecialtypesofACbusbarwithnaturalcooling,aircoolingandwatercoolingbusbarstructurehavebeenproposedandinvestigatedinthispaper.Foreachcoolingscheme,a3Dfinitemodelbasedontheproposedstructurehasbeendevelopedtoperformtheelectromagneticandthermalanalysistopredicttheiroperationbehavior.Comparingtheanalysisresultsofthethreedifferentcoolingpatterns,watercoolinghasmoreadvantagesthantheotherpatternsanditisselectedtobethethermaldissipationpatternfortheACbusbarofITERPFconverterunit.TheapproachtoqualifythesuitablecoolingschemeinthispapercanbeprovidedasareferenceonthethermaldissipationdesignofACbusbarintheconvertersystem.
简介:运用多种方法、多种基组对PF(X3∑-)的平衡结构进行优化计算.用QCISD/6—311G(df)方法得到的平衡结构为RPF=0.1589nm,与实验值RPF=0.15897nm进行比较,最为接近,得出QCISD/6—311G(d,)基组为最优基组;然后对PF(X3∑-)进行单点能扫描计算,用正规方程组拟合Murrell-Sorbie函数,得到相应电子态的势能函数解析式,由势能函数计算了与PF(X3∑-)态相对应的光谱常数,结果与实验数据较为一致.这些数据为反应动力学提供了理论依据.