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11 个结果
  • 简介:在舰载系统和机载系统,当子母惯导之间存在臂长度时,在传递对准中通常先消除臂效应误差再进行对准,以提高对准精度。在弹载环境中人们往往忽视臂效应,受制于弹体空间的限制,弹载惯组中的加速度计通常根据系统体积最小的原则寻找剩余空间布置,此时三个加速度计测量的是弹体三个不同点的加速度,不但存在外臂还存在内臂,导致惯组总体的臂误差。通过深入分析内外臂的形成机理,提出对弹载惯组也应进行臂效应误差补偿,对补偿算法进行了仿真和实验研究。系统半物理仿真表明补偿后在某些弹道条件下可以显著提高弹体攻击精度,其攻击目标误差由120m缩小为26m。

  • 标签: 杆臂效应 内杆臂 弹载惯组 攻击精度
  • 简介:重点介绍了臂效应原理和舰载水下潜器传递对准误差模型,针对潜器用捷联式惯性导航系统(SINS),在释放前摇摆基座上进行初始传递对准时,系统中存在的臂效应误差问题,提出了直接补偿臂干扰加速度和设计低通滤波器的补偿方案.通过计算机仿真:验证了方案可以有效的提高传递对准精度,提供高准确性的导航姿态基准.

  • 标签: 捷联惯性导航系统 杆臂效应:传递对淮:摇摆基座 初始对准 误差补偿 舰载水下潜器
  • 简介:Lithium-aluminum-cobalt-nickeloxideLiAlxCoyNi1xyO2particles,generallyusedascathodeoflithiumbattery,werepreparedbychemicalcoprecipitationfromanaqueoussolutionofLiOH,Al(NO3)3,Co(NO3)2andNi(NO3)2withNH4OH.XRD,SEMandFTIRwereusedtoexaminetheeffectofnickelcontentontheproduct.FTIRpatternsshowedthatincreaseinnickelcontentdecreasedtheabsorptionstrengthofthepeakofspinelstructureoftheproduct,attributedtotheoccupationbynickelinthealuminumsites.Particlesizeandelectricalpropertiesofthelithium-aluminum-cobalt-nickeloxide(abbreviatedasLACNO)particleswerealsodetermined.

  • 标签: LiAlxCoyNi1-x-yO2 Chemical coprecipitation Particle size Electrical
  • 简介:The(2+1)-dimensionalBKPequationintheHirotabilinearformisstudiedduringthiswork.WronskianandGrammiantechniquesareappliedtotheconstructionofWronskianandGrammiansolutionsofthisequation,respectively.ItisshownthatthesesolutionscanbeexpressedasnotonlyPfaffiansbutalsoWronskiansandGrammians.

  • 标签: Wronski行列式 KP方程 双线性形式 可表
  • 简介:The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.

  • 标签: Duffing' s EQUATION SUBHARMONIC TRANSIENT PROCESS
  • 简介:Inthispaper,ahigh-orderfinite-volumeschemeispresentedfortheone-dimensionalscalarandinviscidEulerconservationlaws.TheSimpson’squadratureruleisusedtoachievehigh-orderaccuracyintime.TogetthepointvalueoftheSimpson’squadrature,thecharacteristictheoryisusedtoobtainthepositionsofthegridpointsateachsub-timestagealongthecharacteristiccurves,andthethird-orderandfifth-ordercentralweightedessentiallynon-oscillatory(CWENO)reconstructionisadoptedtoestimatethecellpointvalues.Severalstandardone-dimensionalexamplesareusedtoverifythehigh-orderaccuracy,convergenceandcapabilityofcapturingshock.

  • 标签: EULER方程 有限体积格式 准一维 特征 基础 高阶精度
  • 简介:在现在的纸,包含三个任意的函数为的一个一般解决方案概括(2+1)维的KdV-mKdV方程,它被导出从概括(1+1)维的KdV-mKdV方程,首先借助于Wiess被介绍,小鼓,Carnevale(WTC)截断方法。然后有考虑的几条能量守恒定律的multisymplectic明确的表达被介绍为概括(2+1)维的KdV-mKdV方程基于桥的multisymplectic理论。随后,源于以便以Jacobi椭圆形的功能的合理功能模仿周期的波浪答案一般答案,一个半含蓄的multi-symplectic计划被构造那等价于Preissmann计划。从数字实验的结果,我们能断定multi-symplectic计划能精确地模仿周期的波浪答案概括(2+1)维的KdV-mKdV方程当时近似保存能量守恒定律。

  • 标签: KDV-MKDV方程 KDV-MKDV方程 广义 PREISSMANN格式 JACOBI椭圆函数 辛方法
  • 简介:AhighlyefficientH1-Galerkinmixedfiniteelementmethod(MFEM)ispresentedwithlineartriangularelementfortheparabolicintegro-differentialequation.Firstly,somenewresultsabouttheintegralestimationandasymptoticexpansionsarestudied.Then,thesuperconvergenceoforderO(h2)forboththeoriginalvariableuinH1(π)normandthefluxp=uinH(div,π)normisderivedthroughtheinterpolationpostprocessingtechnique.Furthermore,withthehelpoftheasymptoticexpansionsandasuitableauxiliaryproblem,theextrapolationsolutionswithaccuracyO(h3)areobtainedfortheabovetwovariables.Finally,somenumericalresultsareprovidedtoconfirmvalidityofthetheoreticalanalysisandexcellentperformanceoftheproposedmethod.

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  • 简介:针对1点RANSAC(RandomSampleConsensus)单目视觉EKF(ExtendedKalmanFilter)算法中的滤波发散问题,分析了滤波发散的产生原因,提出了一种基于渐消记忆滤波的1点RANSAC单目视觉姿态估计算法。该算法通过在EKF滤波方程中引入加权因子,逐渐加大当前数据的权重,相应地减少旧数据的权重,有效地扼制了算法中的滤波发散问题。最后通过两组验证性实验验证说明了算法的有效性。实验结果表明:该算法能够有效地解决1点RANSAC单目视觉EKF算法中的滤波发散问题,具有更高的精度。第一组双轴联动实验,航向角的平均误差减小2.4158?,俯仰角平均误差减小0.1782?;第二组偏航轴大角度转动实验,摄像机航向角的估计误差一直保持在1.5?以内。

  • 标签: 1点RANSAC算法 渐消记忆滤波 单目视觉 滤波发散
  • 简介:Perovskite-typeLa1-xCexMnO3(x=0-10%)catalystswerepreparedbyflamespraypyrolysisandtheiractivitiesduringthecatalyticoxidationofbenzenewereexaminedoverthetemperaturerangeof100-450℃.ThestructuralpropertiesandreducibilityofthesematerialswerealsocharacterizedbyX-raydiffraction(XRD),N2adsorption/desorption,H2temperature-programmedreduction(H2-TPR)andX-rayphotoelectronspectroscopy(XPS).TheincorporationofCewasfoundtoimprovethebenzeneoxidationactivity,andtheperovskiteinwhichxwas0.1exhibitedthehighestactivity.Phasecompositionandsurfaceelementalanalysesindicatedthatnon-stoichiometriccompoundswerepresent.TheincorporationofCehadanegligibleeffectonthespecificsurfaceareaoftheperovskitesandhencethisfactorhaslittleimpactonthecatalyticactivity.IntroductionofCe44+resultedinmodificationofthechemicalstatesofbothB-siteionsandoxygenspeciesandfacilitatedthereducibilityoftheperovskite.ThesurfaceMn4+/Mn3+ratiowasincreasedasaresultofCe4+substitution,whileadecreaseinthesurface-adsorbedO/latticeO(Oads/Olatt)ratiowasobserved.Therelationshipbetweenthesurfaceelementalratiosandcatalyticactivitywasestablishedtoallowabetterunderstandingoftheprocessbywhichbenzeneisoxidizedoverperovskites.

  • 标签: 钙钛矿型 氧化铈 催化剂 掺入 火焰 X射线光电子能谱
  • 简介:阴极材料李[CoxNiyMn1?x?y]为锂的O2第二等的电池被一条新线路作为一位先锋用分层的双氢氧化物(LDH)准备了。结果有-NaFeO2结构的分层的阶段在菱形的系统结晶,与有到0.47nm的夹层间距结束的空格组R-3m。X光检查光电子光谱学(XPS)被用来测量公司,Ni和Mn的氧化状态。在结构和李的电气化学的性质上改变Co/Ni/Mn比率的效果[CoxNiyMn1?x?y]O2被X光检查衍射和电气化学的测试调查了。产品表明了相当稳定的骑车行为,与为有Co/Ni/Mn=1/1/1的分层的材料的118mAh/g的一个可逆能力。

  • 标签: 层状正极材料 层状双金属氢氧化物 层状前体 O2 X射线光电子能谱 合成