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一种游动傅科机械编排的捷联惯性间接极区导航算法

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宇航学报 2024年第3期45卷 409-420页

作者：孙新雷尹浩凌富立王玲玲北京航空航天大学机械与控制工程国家级(虚拟仿真)实验教学中心北京100191 莫斯科罗蒙诺索夫国立大学力学数学系莫斯科119991

针对指北方位、游移方位等机械编排的惯性导航系统在极区附近出现计算溢出、导航误差发散、方向基准缺失等问题,本文提出了一种基于游动傅科机械力学编排的捷联惯性间接极区导航算法。首先,推导了传统坐标系和横向坐标系下的游动傅科机... 详细信息

针对指北方位、游移方位等机械编排的惯性导航系统在极区附近出现计算溢出、导航误差发散、方向基准缺失等问题,本文提出了一种基于游动傅科机械力学编排的捷联惯性间接极区导航算法。首先,推导了传统坐标系和横向坐标系下的游动傅科机械编排位置、速度和姿态转换关系,并设计了完整的捷联惯性极区导航流程。其次,在详细分析载体沿经线穿越极点时的导航解算性能基础上,提出了一种游动傅科机械编排的捷联惯性间接极区导航算法。实验结果表明,该算法能够实现传统导航与横向导航方式的平滑切换,并借助横向导航信息解决载体穿越极点时无法导航的难题。

关键词：极区导航惯性导航机械编排游动傅科系横向坐标系

Origin of ULVZs near the African LLSVP: Implications from their distribution and characteristics

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Earthquake Science 2021年第4期34卷 299-309页

作者： An Fan xinlei sun Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 610630China University of Chinese Academy of Sciences Beijing 101400China International Center for Planetary Science College of GeosciencesChengdu University of TechnologyChengdu 610059China

Ultra-low velocity zones(ULVZs)provide important information on the composition and dynamics of the core-mantle boundary(CMB).However,their global distribution and characteristics are not well constrained,especially near African large low-shear velocity provinces(LLSVPs).Here,we used ScS precursor(SdS)and postcursor(ScscS)phases recorded by various seismic networks in Africa and South America to investigate the ULVZ characteristics underlying the South Atlantic *** found no evidence of ULVZs near the SE boundary of South America,but an ULVZ was found within the SW boundary of the African LLSVP,with thicknesses ranging from 11–18 km and reductions in S-wave velocities of 18%–34%.Our results,combined with the global distribution of ULVZs,suggest that thermal activity may be essential to ULVZ ***,subducted slab and mantle flow may also play a key role,depending on the location of the ULVZs.

关键词： ultra-low velocity zone slab subduction mantle flow thermal effect African large low-shear velocity province.

Topography effect on ambient noise tomography using a dense seismic array

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Earthquake Science 2018年第5期31卷 291-300页

作者： Shuang Wang xinlei sun State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

With the rapid increase of dense seismic array deployment, more and more ambient noise studies have been applied on short period surface waves tomography. For arrays with inter-station distance of several hundred meters,the effect of surface topography has to be considered. In this study, we investigate topography effect on ambient noise surface wave tomography using synthetic data from different topographic models. Our travel times are synthetized considering surface topography, and shear wave inversions are performed by incorporating and not incorporating topography respectively. Our inversion results suggest that topography does affect subsurface shear wave velocity inversion. If topography is not considered, although the pattern of the structure may be recovered reasonably well, the depth distribution of velocity structure can be distorted. The maximum distortion depth is generally correlated with the relief of the topography and the amplitude of the velocity anomalies. Finally, our example of real data inversion in a mountain area demonstrates good correlation between shear velocity and the geological settings, as well as the core sample in that area.

关键词： topography effect dense array ambient noise tomography

Three dimensional shear wave velocity structure of the crust and upper mantle beneath China from ambient noise surface wave tomography

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Earthquake Science 2010年第5期23卷 449-463页

作者： xinlei sun Xiaodong Song Sihua Zheng Yingjie Yang Michael H. Ritzwoller Department of Geology University of Illinois at Urbana-Champaign Urbana IL 61801 USA Institute of Earthquake Science China Earthquake Administration Beijing 100036 China CIEI Department of Physics University of Colorado at Boulder Boulder CO 80309 USA

We determine the three-dimensional shear wave velocity structure of the crust and upper mantle in China using Green＇s functions obtained from seismic ambient noise cross-correlation. The data we use are from the China National Seismic Network, global and regional networks and PASSCAL stations in the region. We first acquire cross-correlation seismograms between all possible station pairs. We then measure the Rayleigh wave group and phase dispersion curves using a frequency-time analysis method from 8 s to 60 s. After that, Rayleigh wave group and phase velocity dispersion maps on 1°by 1°spatial grids are obtained at different periods. Finally, we invert these maps for the 3-D shear wave velocity structure of the crust and upper mantle beneath China at each grid node. The inversion results show large-scale structures that correlate well with surface geology. Near the surface, velocities in major basins are anomalously slow, consistent with the thick sediments. East-west contrasts are striking in Moho depth. There is also a fast mid-to-lower crust and mantle lithosphere beneath the major basins surrounding the Tibetan plateau （TP） and Tianshan （Junggar, Tarim, Ordos, and Sichuan）. These strong blocks, therefore, appear to play an important role in confining the deformation of the TP and constraining its geometry to form its current triangular shape. In northwest TP in Qiangtang, slow anomalies extend from the crust to the mantle lithosphere. Meanwhile, widespread, a prominent low-velocity zone is observed in the middle crust beneath most of the central, eastern and southeastern Tibetan plateau, consistent with a weak （and perhaps mobile） middle crust.

关键词： ambient noise surface wave tomography crust and upper mantle China

PKM2 controls the degranulation of secondary and tertiary granules in neutrophils by phosphorylating SNAP-23

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Cellular & Molecular Immunology 2021年第8期18卷 2048-2050页

作者： xinlei sun Dong Wang Yan Wang Lei Ye Fujie Shi Shuang Qu Hongwei Liang Ke Zen School of Life Science and Technology China Pharmaceutical UniversityNanjingJiangsuChina Department of Pharmacology School of PharmacyChina Pharmaceutical UniversityNanjingJiangsuChina School of Life Sciences Nanjing UniversityNanjingJiangsuChina Department of Gastroenterology and Hepatology Jinling HospitalMedical School of Nanjing UniversityNanjingChina

Polymorphonuclear neutrophils(PMNs)possess multiple distinct types of cytoplasmic granules:secondary granules,tertiary granules,and azurophil granules[1].It has been suggested that PMN degranulation is controlled by exocytotic machinery comprising membrane-specific SNARE proteins,soluble N-ethylmaleimide sensitive factor(NSF)and soluble NSF-attaching proteins[2].

关键词： PKM2 neutrophils tertiary

Major Miocene geological events in southern Tibet and eastern Asia induced by the subduction of the Ninetyeast Ridge

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Acta Geochimica 2018年第3期37卷 395-401页

作者： xinlei sun Wei-dong sun Yong-bin Hu Wei Ding Trevor Ireland Mei-zhen Zhan Ji-qiang Liu Ming-xing Ling Xing Ding Zhao-feng Zhang Wei-ming Fan State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640 China Center of Deep Sea Research Institute of OceanographyChinese Academy of Sciences Qingdao 266071 China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences Beijing 100101China CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China University of the Chinese Academy of Sciences Beijing 100049 China Research School of Earth Sciences The Australian National University Canberra ACT 2601 Australia

Cenozoic adakitic rocks in the Gangdese changed from barren continental melts to ore-forming slab melts at * 23 Ma. The distribution and chemical characteristics of the ore-forming adakites point to an association with the Ninetyeast Ridge. The subduction of the thick,rigid Ninetyeast Ridge changed the geometry and rheology of the eastern Tibetan Plateau lithosphere and asthenosphere, restrained the eastward escape of asthenospheric mantle as well as continental fragments, and promoted the uplift and building of the Tibetan Plateau, which consequently changed the tectonic and climatic regimes in eastern Asia.

关键词： Ridge subduction Eastern Tibetan Plateau Cenozoic mineralization Seismic anomaly

Distribution and Characteristics of ULVZs near the Boundary of the Africa LLSVP

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Distribution and Characteristics of ULVZs near the Boundary ...

地球内核顶部300km速度和衰减各向异性的区域变化

2019年中国地球科学联合学术年会

作者： An Fan xinlei sun Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academic of Sciences

ULVZs can provide important information of CMB compositions and dynamics. However,their distribution and characteristics are not well constrained. Here we use ScS precursor (SdS) and the postcursor (ScscS) phases recorded by USArray and various seismic networks in Africa to study the ULVZs near the northwest and southwest boundary of the Africa LLSVP. We use the Flip and Reverse Stacking (FRS) method (Zhao et al, 2017) to

关键词： Distribution and Characteristics of ULVZs near the Boundary of the Africa LLSVP

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地球物理学报 2020年第6期63卷 2199-2209页

作者：秦加岭孙新蕾张鹏范安同位素地球化学国家重点实验室中国科学院广州地球化学研究所广州510640 中国科学院大学北京100049

衰减结构是地球内核的重要性质,它可以与地球内核的速度结构结合,对内核的形成和演化机制提供更全面的信息.本文系统收集了1991年到2014年全球、区域和临时地震台网的PKPDF和PKPBC数据,研究了澳大利亚、非洲和太平洋中部下方内核顶部30... 详细信息

衰减结构是地球内核的重要性质,它可以与地球内核的速度结构结合,对内核的形成和演化机制提供更全面的信息.本文系统收集了1991年到2014年全球、区域和临时地震台网的PKPDF和PKPBC数据,研究了澳大利亚、非洲和太平洋中部下方内核顶部300km的速度和衰减各向异性结构.速度结果表明,澳大利亚下方内核的速度没有明显的各向异性,但是非洲和太平洋中部下方的内核具有明显的各向异性,且非洲的速度各向异性强于太平洋中部.同时,相对于AK135模型,澳大利亚的平均速度快0.5%,而非洲和太平洋中部的平均速度与参考模型没有明显差异.对于内核的衰减结构,我们得到以下结果:1)在东西方向,内核顶部200km左右的区域,澳大利亚的衰减最强(Q值在400左右),非洲和太平洋中部的Q值分别在600和500左右.2)澳大利亚下方的内核衰减没有明显的各向异性,非洲和太平洋中部下方的内核衰减存在明显的各向异性.此外,内核在非洲地区的衰减各向异性强于太平洋中部的各向异性.3)最后,内核中三个区域的速度和衰减具有良好的相关性,即高/低速对应于高/低衰减.考虑到以上结果以及三个区域的位置,我们认为内核顶部的速度和衰减结构都存在区域变化,而不是简单的半球变化.这种区域变化很可能是由于核幔边界热结构的不均一性和内核耦合,使得内核顶部的不同区域在形成过程中受不同的变形影响,从而形成铁晶体不同的生长和排列,引发了不同的各向异性特征.

关键词：地球内核各向异性横向变化衰减

利用密集地震台网高频环境噪声研究广东新丰江库区浅层地下结构

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地球物理学报 2018年第2期61卷 593-603页

作者：王爽孙新蕾秦加岭何立朋邓阳凡同位素地球化学国家重点实验室中国科学院广州地球化学研究所广州510640 中国科学院大学北京100049

广东河源新丰江水库位于华南典型断层上,自1959年水库蓄水以来,库区地震活动性明显增强,并发生了6.1级触发地震.然而我们对其地下结构的了解还远远不够,对库区地震的研究也因此存在很多不确定性.为了研究库区浅层地下结构,我们在2015年... 详细信息

广东河源新丰江水库位于华南典型断层上,自1959年水库蓄水以来,库区地震活动性明显增强,并发生了6.1级触发地震.然而我们对其地下结构的了解还远远不够,对库区地震的研究也因此存在很多不确定性.为了研究库区浅层地下结构,我们在2015年初在新丰江库区人字石断裂周边布设了42个短周期地震仪的密集地震台网.台间距大约为100~500m,时间跨度为1个月.我们对获得的每个台站的连续信号分段进行处理,并对任意台站对的信号进行互相关和叠加处理,恢复所有台站对间的经验格林函数(EGF).然后利用多次滤波分析方法测量瑞利波群速度频散曲线,并反演该区域的群速度分布和三维剪切波速度结构.我们的结果表明,对于这样比较密集的台站间距,高频(0.2~1.2s)频散信号基本可以得到很好的恢复,且该频段信号对浅层地下结构(<1km)较为敏感.剪切波速度分布表明该区域人字石断裂位置出现明显的低速分布,并且低速区在断裂南端向两侧延伸,有可能代表与人字石断裂交错的小断裂区域.同时,人字石断裂把该区域划分成了东西两部分,两侧整体上呈现高速异常,与地表山丘相吻合.我们的结果得到了新丰江人字石断裂附近的近地浅层的小尺度精细速度结构,为进一步理解该区域的构造以及地震发生提供了重要依据.

关键词：新丰江水库密集台网环境噪声层析成像