Parameterization of two-dimensional seismic velocity fields using the Haar wavelet

2012 ◽  
Author(s):  
Helcio Moreira Perin ◽  
Wilson Mouzer Figueiró
Keyword(s):  
Seismic Velocity ◽  
Haar Wavelet ◽  
Velocity Fields ◽  
Two Dimensional

scholarly journals SEISMIC TOMOGRAPHY USING METROPOLIS METHOD OF VELOCITY FIELDS PARAMETERIZED BY HAAR WAVELET SERIES

2016 ◽  
Vol 34 (2) ◽  
Author(s):  
Alexsandro Guerra Cerqueira ◽  
Wilson Mouzer Figueiró ◽  
Paulo Eduardo Miranda Cunha
Keyword(s):  
Velocity Field ◽  
Seismic Tomography ◽  
Seismic Waves ◽  
Seismic Velocity ◽  
Haar Wavelet ◽  
Velocity Fields ◽  
Metropolis Method ◽  
Geological Models ◽  
Qualitative Models ◽  
Wavelet Series

ABSTRACT. The representation of compressional seismic waves velocity fields from geological models through numerical parameters has a strong geophysical importance, because, it makes possible to quantify such qualitative models, allowing its mathematical manipulation. In this way, the parameterization by Haar wavelet series may be seen as an attractive alternative.Keywords: parameterization, Haar wavelet series, pyramid algorithm, seismic tomography, seismic velocity field, traveltime data, Metropolis method. RESUMO. A representação de campos de velocidades sísmicas compressionais, através de parâmetros numéricos, é de importância básica na geofísica, pois torna possível a quantificação de modelos, antes qualitativos, permitindo assim que sejam matematicamente manipulados. A parametrização por série ondaleta Haar pode ser vista como uma alternativa atrativa para quantificar tais modelos...Palavras-chave: parametrização, série ondaleta Haar, inversão sísmica tomográfica, campo de velocidade sísmica, dados de tempo de trânsito, método Metropolis.

scholarly journals Quasi-periodic forces and conditionally averaged characteristics of unsteady cavitation flow around a hydrofoil

2021 ◽  
Vol 2119 (1) ◽  
pp. 012030
Author(s):  
E I Ivashchenko ◽  
M Yu Hrebtov ◽  
R I Mullyadzhanov
Keyword(s):  
Reynolds Number ◽  
Liquid Phase ◽  
High Reynolds Number ◽  
Velocity Fields ◽  
Large Eddy Simulations ◽  
Two Dimensional ◽  
Cavitation Flow ◽  
Large Eddy ◽  
High Reynolds ◽  
Conditional Averaging

Abstract Large-eddy simulations are performed to investigate the cavitating flow around two dimensional hydrofoil section with angle of attack of 9° and high Reynolds number of 1.3×106. We use the Schnerr-Sauer model for accurate phase transitions modelling. Instantaneous velocity fields are compared successfully with PIV data using the methodology of conditional averaging to take into account only the liquid phase characteristics as in PIV. The presence of two frequencies in a spectrum corresponding to the full and partial cavity detachments is analysed.

Conditions for the Separability of Objects in Two-Dimensional Velocity Fields

1992 ◽  
Vol 35 (4) ◽  
pp. 484-491
Author(s):  
Stephan Foldes
Keyword(s):  
Velocity Field ◽  
Directed Graph ◽  
Velocity Fields ◽  
Sufficient Condition ◽  
Two Dimensional ◽  
Jordan Curves ◽  
Directed Cycles

AbstractWe consider the directed graph representing the obstruction relation between objects moving along the streamlines of a two-dimensional velocity field. A collection of objects is sequentially separable if and only if the corresponding graph has no directed cycles. A sufficient condition for this is the permeability of closed Jordan curves.

scholarly journals The Dark Matter Content of Barred Spiral Galaxies

2004 ◽  
Vol 220 ◽  
pp. 277-278
Author(s):  
Glen Petitpas ◽  
Mousumi Das ◽  
Peter Teuben ◽  
Stuart Vogel
Keyword(s):  
Dark Matter ◽  
Spiral Galaxies ◽  
Velocity Fields ◽  
Matter Content ◽  
Two Dimensional ◽  
Disk Model ◽  
Barred Galaxies ◽  
Preliminary Results ◽  
Nearby Galaxies ◽  
Barred Spiral Galaxies

Two-dimensional velocity fields have been used to determine the dark matter properties of a sample of barred galaxies taken from the BIMA Survey of Nearby Galaxies (SONG). Preliminary results indicate that the maximal disk model is not appropriate in several galaxies in our sample, but higher resolution results will be needed to confirm this.

Sign in / Sign up

Export Citation Format

Share Document