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101.
一种低成本、低精度SINS/GPS组合导航系统及试验研究 总被引:3,自引:0,他引:3
在SINS(捷联式惯性导航系统)与GPS组合时,航向角的可观测性较弱,经过卡尔曼滤波后,航向角误差虽有所改善,但仍呈发散趋势,当采用低成本、低精度SINS时,该趋势进一步加剧。为了抑制该发散趋势,针对某型低成本、低精度SINS硬件组成(包括AHRS(姿态和航向参考系统)与IMU(惯性测量器件))的特点,提出了利用AHRS代替SINS航向角信息的方法。实际静态与动态试验表明,利用该方法可有效地抑制组合系统航向角的发散趋势,定位精度较高。 相似文献
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30��N���ණ����ƽ��ĵ�Ƶ�仯������ENSO�Ĺ�ϵ 总被引:2,自引:0,他引:2
????1992??12???2007??5?μ??????????о???????????仯??????????????????14?????????????30??N??????????????????????????57.7 mm??40.9 mm??????????????????????????????о?????????????????????ζ??????SOI????????????????????????????????????????????SOI???????30??N??????SLA??SOI???????????????γ??????????SLA??SOI???к???????????????????????????糡??????????????????SLA??γ???????????????????????????????30??N ???????????????????????????????????????????????????????????????????????????????????????SLA??????????·???????u??????????????????????????30??N ?????????????????????????????u??????????????70???????23????????????u????????SLA??SOI????????????????????????????????????????е?????????????30??N ???????????????????u????SOI???????ENSO????????????????????????糡???????????糡???γ????????????????????仯???????????á?????ENSO???????????????????????????? 相似文献
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Danqing?HuangEmail author Peiwen?Yan Jian?Zhu Yaocun?Zhang Xueyuan?Kuang Jing?Cheng 《Theoretical and Applied Climatology》2018,131(1-2):55-68
Worldwide, the majority of rapidly growing neighborhoods are found in the Global South. They often exhibit different building construction and development patterns than the Global North, and urban climate research in many such neighborhoods has to date been sparse. This study presents local-scale observations of net radiation (Q * ) and sensible heat flux (Q H ) from a lightweight low-rise neighborhood in the desert climate of Andacollo, Chile, and compares observations with results from a process-based urban energy-balance model (TUF3D) and a local-scale empirical model (LUMPS) for a 14-day period in autumn 2009. This is a unique neighborhood-climate combination in the urban energy-balance literature, and results show good agreement between observations and models for Q * and Q H . The unmeasured latent heat flux (Q E ) is modeled with an updated version of TUF3D and two versions of LUMPS (a forward and inverse application). Both LUMPS implementations predict slightly higher Q E than TUF3D, which may indicate a bias in LUMPS parameters towards mid-latitude, non-desert climates. Overall, the energy balance is dominated by sensible and storage heat fluxes with mean daytime Bowen ratios of 2.57 (observed Q H /LUMPS Q E )–3.46 (TUF3D). Storage heat flux (ΔQ S ) is modeled with TUF3D, the empirical objective hysteresis model (OHM), and the inverse LUMPS implementation. Agreement between models is generally good; the OHM-predicted diurnal cycle deviates somewhat relative to the other two models, likely because OHM coefficients are not specified for the roof and wall construction materials found in this neighborhood. New facet-scale and local-scale OHM coefficients are developed based on modeled ΔQ S and observed Q * . Coefficients in the empirical models OHM and LUMPS are derived from observations in primarily non-desert climates in European/North American neighborhoods and must be updated as measurements in lightweight low-rise (and other) neighborhoods in various climates become available. 相似文献
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D. Maričić B. Vršnak M. Dumbović T. Žic D. Roša D. Hržina S. Lulić I. Romštajn I. Bušić K. Salamon M. Temmer T. Rollett A. Veronig N. Bostanjyan A. Chilingarian B. Mailyan K. Arakelyan A. Hovhannisyan N. Mujić 《Solar physics》2014,289(1):351-368
We study heliospheric propagation and some space weather aspects of three Earth-directed interplanetary coronal mass ejections (ICMEs), successively launched from the active region AR 11158 in the period 13?–?15 February 2011. From the analysis of the ICME kinematics, morphological evolution, and in situ observations, we infer that the three ICMEs interacted on their way to Earth, arriving together at 1 AU as a single interplanetary disturbance. Detailed analysis of the in situ data reveals complex internal structure of the disturbance, where signatures of the three initially independent ICMEs could be recognized. The analysis also reveals compression and heating of the middle ICME, as well as ongoing magnetic reconnection between the leading and the middle ICME. We present evidence showing that the propagation of these two, initially slower ICMEs, was boosted by the fastest, third ICME. Finally, we employ the ground-based cosmic ray observations, to show that this complex disturbance produced a single cosmic ray event, i.e., a simple Forbush decrease (FD). The results presented provide a better understanding of the ICME interactions and reveal effects that should be taken into account in forecasting of the arrival of such compound structures. 相似文献
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CINRAD/SA雷达伺服电机连续故障诊断分析 总被引:1,自引:0,他引:1
CINRAD/SA天气雷达投入业务运行以来,在天线伺服系统方面出现了很多次故障,而直流方位电机是天线伺服系统的主要组成部分也是发生故障较多的部件之一。2014年福建长乐CINRAD/SA天气雷达在重大天气保障过程中,连续发生方位电机卡死造成雷达停机和测速机性能降低引起天线转速不稳造成雷达产品异常的故障;根据天线控制信号流程,通过运行雷达RDASOT测试程序、测量直流方位电机阻值、测量测速机反馈电压等方法,分析其故障的成因,对雷达伺服直流电机故障分析及解决方法有重要的指导作用。 相似文献
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