A three-point velocity estimation method for two-dimensional coarse-grained imaging data

被引:1
|
作者
Losada, J. M. [1 ]
Helgeland, A. D. [1 ]
Terry, J. L. [2 ]
Garcia, O. E. [1 ]
机构
[1] UiT Arctic Univ Norway, Dept Phys & Technol, N-9037 Tromso, Norway
[2] MIT Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA
关键词
SCRAPE-OFF LAYER; ALCATOR C-MOD; TIME-DELAY ESTIMATION; EDGE TURBULENCE; INTERMITTENT FLUCTUATIONS; PLASMA FLUCTUATIONS; VELOCIMETRY; DRIFT; FLOW;
D O I
10.1063/5.0197251
中图分类号
TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
Time delay and velocity estimation methods have been widely studied subjects in the context of signal processing, with applications in many different fields of physics. The velocity of waves or coherent fluctuation structures is commonly estimated as the distance between two measurement points divided by the time lag that maximizes the cross correlation function between the measured signals, but this is demonstrated to result in erroneous estimates for two spatial dimensions. We present an improved method to accurately estimate both components of the velocity vector, relying on three non-aligned measurement points. We introduce a stochastic process describing the fluctuations as a superposition of uncorrelated pulses moving in two dimensions. Using this model, we show that the three-point velocity estimation method, using time delays calculated through cross correlations, yields the exact velocity components when all pulses have the same velocity. The two- and three-point methods are tested on synthetic data generated from realizations of such processes for which the underlying velocity components are known. The results reveal the superiority of the three-point technique. Finally, we demonstrate the applicability of the velocity estimation on gas puff imaging data of strongly intermittent plasma fluctuations due to the radial motion of coherent, blob-like structures at the boundary of the Alcator C-Mod tokamak.
引用
收藏
页数:9
相关论文
共 50 条
  • [21] On the Unique Solvability of a Three-Point Problem for Partial Differential Equation in a Two-Dimensional Domain
    Kalenyuk P.I.
    Volyans’ka I.I.
    Il’kiv V.S.
    Nytrebych Z.M.
    Journal of Mathematical Sciences, 2020, 246 (2) : 170 - 187
  • [22] Enhancement of the three-point bending behavior of a coarse-grained NiTi shape memory alloy with surface heterogeneous gradient microstructure and compressive residual stress
    Yan, Kai
    Wei, Pengbo
    Wang, Hao
    Sun, Qingping
    JOURNAL OF ALLOYS AND COMPOUNDS, 2024, 983
  • [23] A Randomized Parallel Three-Dimensional Convex Hull Algorithm for Coarse-Grained Multicomputers
    F. Dehne
    X. Deng
    P. Dymond
    A. Fabri
    A. A. Khokhar
    Theory of Computing Systems, 1997, 30 : 547 - 558
  • [24] Three-dimensional numerical modeling of coarse-grained elastic deposition in sedimentary basins
    Ritchie, BD
    Hardy, S
    Gawthorpe, RL
    JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 1999, 104 (B8) : 17759 - 17780
  • [25] A randomized parallel three-dimensional convex hull algorithm for coarse-grained multicomputers
    Dehne, F
    Deng, X
    Dymond, P
    Fabri, A
    Khokhar, AA
    THEORY OF COMPUTING SYSTEMS, 1997, 30 (06) : 547 - 558
  • [26] Nonparametric two-dimensional point spread function estimation for biomedical imaging
    Doukoglou, T.D.
    Hunter, I.W.
    Kearney, R.E.
    Medical and Biological Engineering and Computing, 1993, 31 (03): : 277 - 283
  • [27] Two-dimensional scattering patterns of coarse-grained molecular dynamics model of filled polymer gels during uniaxial expansion
    Hagita, Katsumi
    POLYMER, 2019, 166 : 155 - 168
  • [28] Coarse-Grained Approach to Simulate Signatures of Excitation Energy Transfer in Two-Dimensional Electronic Spectroscopy of Large Molecular Systems
    Zhong, Kai
    Nguyen, Hoang Long
    Do, Thanh Nhut
    Tan, Howe-Siang
    Knoester, Jasper
    Jansen, Thomas L. C.
    JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 2024, 20 (14) : 6111 - 6124
  • [29] Coarse-Grained Model for N2-N Relaxation in Hypersonic Shock Conditions using Two-Dimensional Bins
    Zhu, Tong
    Li, Zheng
    Levin, Deborah A.
    30TH INTERNATIONAL SYMPOSIUM ON RAREFIED GAS DYNAMICS (RGD 30), 2016, 1786
  • [30] Two-dimensional estimation of the electrohysterographic conduction velocity
    Rabotti, Chiara
    Mischi, Massimo
    2010 ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2010, : 4262 - 4265