Seismic fault preserving diffusion     

《Journal of Applied Geophysics》2007,61(2):132-141

This paper focuses on the denoising and enhancing of 3-D reflection seismic data. We propose a pre-processing step based on a non-linear diffusion filtering leading to a better detection of seismic faults. The non-linear diffusion approaches are based on the definition of a partial differential equation that allows us to simplify the images without blurring relevant details or discontinuities. Computing the structure tensor which provides information on the local orientation of the geological layers, we propose to drive the diffusion along these layers using a new approach called SFPD (Seismic Fault Preserving Diffusion). In SFPD, the eigenvalues of the tensor are fixed according to a confidence measure that takes into account the regularity of the local seismic structure. Results on both synthesized and real 3-D blocks show the efficiency of the proposed approach.  相似文献   

Application of electron spin resonance (ESR) dating to ductile shearing: Examples from the Qinling orogenic belt,China     

《Journal of Structural Geology》2016

Shear zones are common structures in orogenic belts and elucidation of the tectonic evolution of these orogenic belts to a large degree depends on understanding the kinematics and timing of shear deformation. However, there is a lack of an accurate, fast and convenient way to determine the timing of deformation. In this paper, we apply the ESR (electron spin-resonance spectroscopy) dating method to three syntectonic quartz veins from the Funiushan tectonic belt in the Qinling orogenic belt in central China. The results agree well with the available ages of deformation in the area obtained through other dating methods. This demonstrates the accuracy and feasibility of using the ESR method to date quartz crystals formed during deformation. The method is fast and convenient, and satisfies the accuracy requirement. It is an effective means for determining the timing of deformation, especially in areas with intensive fluid activity during deformation.  相似文献   

Integrity monitoring-based ratio test for GNSS integer ambiguity validation     

Li  Liang  Li  Zishen  Yuan  Hong  Wang  Liang  Hou  Yanqing 《GPS Solutions》2016,20(3):573-585

GPS Solutions - The combination of multiple global navigation satellite systems (GNSSs) is able to improve the accuracy and reliability, which is beneficial for navigation in safety–critical...  相似文献   

Vibration characteristics of frozen soil under moving track loads     

AiPing Tang  AnPing Zhao  AiHua Wen 《寒旱区科学》2015,7(4):414-420

Vibration due to moving traffic loads is an important factor which induces frozen soil damage; this paper analyzed these vibration characteristics of frozen soil foundation under track loads. Firstly, seismic observation array(SOA) technology was applied to monitor the three dimensional dynamic characteristics of frozen soil under movable track load in a permafrost region and seasonal frozen soil area. Secondly, a numerical simulation for the response of frozen soil under movable track load was performed based on finite element analysis(FEA). The results show that dynamic characteristics of frozen soil in perpendicular and parallel direction of the track are obviously different. In the direction perpendicular to the track, the vertical acceleration amplitude had an abrupt increase in the 9–10 m from the track line. In the direction parallel to the track, the acceleration in vertical and horizontal direction had a quick attenuation compared to the other direction. Lastly, various parameters were analyzed for the purpose of controlling the dynamic response of frozen soil and the vibration attenuation in frozen soil layer.  相似文献   

通信受限下基于终端滑模和指对数滑模方法的编队航天器姿态协同控制     

易航  陈雪芹  刘明 《南京气象学院学报》2021,13(1):29-40

针对星间通信时延和信号量化情形下编队航天器,研究对应的姿态协同控制器设计问题.首先,为节省编队航天器星间通信的带宽资源,提出基于信号量化的星间数据通信策略,并设计了一种终端滑模姿态协同控制器以保证航天器编队姿态同步系统的渐近稳定;其次,考虑到航天器间可能存在通信时延,考虑基于信号量化的通信策略,提出一种基于指对数滑模面的编队航天器协同控制器设计方法,能保证编队航天器在有限时间内达到期望姿态;最后基于包含4个航天器的编队系统,通过仿真验证了所提出的协同控制方法的有效性.  相似文献   

Morphology of craters generated by hypervelocity impacts of micron‐sized polypyrrole‐coated olivine particles     

Y. W. Li  S. Bugiel  M. Trieloff  Jon K. Hillier  F. Postberg  M. C. Price  A. Shu  K. Fiege  L. A. Fielding  S. P. Armes  Y. Y. Wu  E. Grün  R. Srama 《Meteoritics & planetary science》2014,49(8):1375-1387

To understand the process of cosmic dust particle impacts and translate crater morphology on smoothed metallic surfaces to dust properties, correct calibration of the experimental impact data is needed. This article presents the results of studies of crater morphology generated by impacts using micron‐sized polypyrrole (PPy)‐coated olivine particles. The particles were accelerated by an electrostatic dust accelerator to high speeds before they impacted onto polished aluminum targets. The projectile diameter and velocity ranges were 0.3–1.2 μm and 3–7 km s^?1. After impact, stereopair images of the craters were taken using scanning electron microscope and 3‐D reconstructions made to provide diameter and depth measurements. In this study, not just the dimensions of crater diameters and depths, but also the shape and dimensions of crater lips were analyzed. The craters created by the coated olivine projectiles are shown to have complicated shapes believed to be due to the nonspherical shape of the projectiles.  相似文献   

基于小波阈值算法的海杂波信号降噪   总被引：3，自引：0，他引：3       下载免费PDF全文

王福友  刘刚  袁赣南 《海洋测绘》2010,30(4):19-22

为有效提取噪声背景下的海杂波信号,针对海杂波信号非线性非平稳的特点,提出基于小波阈值算法对实测海杂波数据去噪。在噪声水平未知条件下,提出基于噪声主要在高频段且能量较小、信号主要集中在低频段思想的噪声判断准则。为验证小波去噪效果,将该算法对含有噪声的海杂波实测数据进行去噪,采用均方差和降噪信号信噪比两项指标衡量去噪效果,并与均值和中值等去噪方法对比,小波算法在这两项指标均优于其他算法;此外,实验结果还表明,db2小波在双曲线阈值函数和HeurSure阈值模式下优于其他小波去噪效果。  相似文献   

高级在轨系统在高分辨率遥感卫星中的应用     

李世忠  胡莘  顾学迈  吕源  胡国军 《测绘学院学报》2009,(2)

高级在轨系统AOS是空间数据系统咨询委员会CCSDS制定的关于星-星和星-地的数据管理系统。结合AOS系统协议和高分辨率遥感卫星在轨获取的各类载荷数据实际特点,设计了一种适应于高分辨率遥感卫星的空间数据处理系统。该系统把多种载荷产生的不同数据速率、不同字节大小、不同级别传输要求、不同延时要求的数据进行封装,形成统一的虚拟信道数据单元VCDU格式;并把各条虚拟信道上VCDU复接成连续的数据流经星地物理信道传输。仿真试验证明,该系统方案有效地解决了高分辨率遥感卫星多种载荷数据的组织、管理和传输问题,为后续的测绘和遥感处理奠定了可靠的数据基础。  相似文献   

MUSIC算法在矢量水听器阵中的应用研究     

王绪虎  田坦 《海洋技术学报》2006,25(3):82-85

文中推导了阵元为矢量水听器时的MU S IC算法。对直线阵情况进行了计算机仿真,结果表明,矢量阵MU-S IC算法与声压阵相比具有更高的方位分辨力。  相似文献   

基于AutoCAD三维海洋平台结构模型实用技术研究     

彭辉  聂武 《海洋工程》2007,25(3):26-31

以一个常见桩腿结构为例,介绍使用AutoCAD建立海洋平台结构三维数字模型。提取结构零件属性、生成零件明细表、合并所有零件、构造整个桩腿结构三维实体模型。查询桩腿结构质量和质心,自动生成桩腿结构视图的方法和操作过程。说明基于通用软件进行海洋平台结构三维数字模型的开发与应用切实可行。  相似文献