A DEDISPERSION TRANSFORM FOR SOUND PROPAGATION IN SHALLOW WATER WAVEGUIDE

For sound propagation in a shallow water waveguide, a dedispersion transform which can remove the dispersive effect of signal is described in this paper. The transform is a modified Fourier transform with two variables: translation and dispersion. Dispersive effect of signal for normal modes can be removed when these two variables match to real parameters. The validity of the present approach is verified in simulation and real data processing.

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Mid-frequency Sound Propagation, Reverberation, and Geoacoustic Inversion in Shallow Water

10.21236/ada542289 ◽

2010 ◽

Author(s):

Jie Yang

Keyword(s):

Shallow Water ◽

Sound Propagation ◽

Geoacoustic Inversion ◽

Frequency Sound

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Under-ice shallow-water sound propagation and communication in the Baltic Sea

10.1121/1.4800515 ◽

2013 ◽

Author(s):

Erland Sangfelt ◽

Sven Ivansson ◽

Ilkka Karasalo

Keyword(s):

Baltic Sea ◽

Shallow Water ◽

Sound Propagation ◽

The Baltic Sea ◽

The Baltic

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Erratum to : Numerical solutions of parabolic equation method using Douglas operator scheme in shallow water acoustic sound propagation

The Journal of the Marine Acoustics Society of Japan ◽

10.3135/jmasj.29.110 ◽

2002 ◽

Vol 29 (2) ◽

pp. 110-110

Keyword(s):

Parabolic Equation ◽

Shallow Water ◽

Numerical Solutions ◽

Sound Propagation ◽

Equation Method ◽

Parabolic Equation Method ◽

Operator Scheme

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syris: a flexible and efficient framework for X-ray imaging experiments simulation

Journal of Synchrotron Radiation ◽

10.1107/s1600577517012255 ◽

2017 ◽

Vol 24 (6) ◽

pp. 1283-1295 ◽

Cited By ~ 4

Author(s):

Tomáš Faragó ◽

Petr Mikulík ◽

Alexey Ershov ◽

Matthias Vogelgesang ◽

Daniel Hänschke ◽

...

Keyword(s):

Motion Estimation ◽

Data Processing ◽

Graphics Processing Units ◽

High Speed ◽

Real Data ◽

Estimation Accuracy ◽

Processing Parameter ◽

X Ray ◽

X Ray Imaging ◽

Imaging Conditions

An open-source framework for conducting a broad range of virtual X-ray imaging experiments,syris, is presented. The simulated wavefield created by a source propagates through an arbitrary number of objects until it reaches a detector. The objects in the light path and the source are time-dependent, which enables simulations of dynamic experiments,e.g.four-dimensional time-resolved tomography and laminography. The high-level interface ofsyrisis written in Python and its modularity makes the framework very flexible. The computationally demanding parts behind this interface are implemented in OpenCL, which enables fast calculations on modern graphics processing units. The combination of flexibility and speed opens new possibilities for studying novel imaging methods and systematic search of optimal combinations of measurement conditions and data processing parameters. This can help to increase the success rates and efficiency of valuable synchrotron beam time. To demonstrate the capabilities of the framework, various experiments have been simulated and compared with real data. To show the use case of measurement and data processing parameter optimization based on simulation, a virtual counterpart of a high-speed radiography experiment was created and the simulated data were used to select a suitable motion estimation algorithm; one of its parameters was optimized in order to achieve the best motion estimation accuracy when applied on the real data.syriswas also used to simulate tomographic data sets under various imaging conditions which impact the tomographic reconstruction accuracy, and it is shown how the accuracy may guide the selection of imaging conditions for particular use cases.

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