We are studying experimentally the behavior of jets in flute-like instruments. At the time being most models for jet oscillations are based on linear jet instability analysis described by Rayleigh. But there is no clear model for the initial perturbations induced by transverse acoustic velocity. Aiming to understand and describe the origin of the perturbation, we are currently investigating the...

Because predictive decon fails on the Ricker wavelet, earlier we devised an extension to non-minimum phase wavelets (Yang et al, 2011). It showed remarkable clarity of seismogram polarity. Here we improve our method by a log spectral parameterization. Another innovation here is correctly handling time-variable gain. Since filtering does not commute with TV gain, gain is now done after decon (no...

The complex interactions existing between turbulence and mixing in a bluffbody stabilised flame configuration is investigated by means of a wavelet crosscorrelation analysis on Large Eddy Simulations. The combined approach allows to better point out typical features of unsteady turbulent flows with mixing through the characterisation of the processes involved both in time and scales. The wavele...

The landslides cause several casualties and economic losses all over the world. Studies show that most casualties happen within the first 18-35 minutes after the burial. This demands life-detecting systems to be available immediately on the spot after the disaster. A suggested approach is deploying multiple units of these instruments across the country. Main constraint in developing countries f...

An optical identification system of a three-dimensional (3D) random phase object by use of speckle patterns in different propagation distances is proposed and evaluated experimentally. The 3D random phase object is used as a 3D key. It can be secure when the scattering is strong enough because the interferometric measurement is not applied. The identification is implemented by evaluating crossc...

In this paper we present a new approach for clustering data. The clustering metric used is the normalized crosscorrelation, also known as similarity, instead of the traditionally used Euclidean distance. The main advantage of this metric is that it depends on the signal shape rather than its amplitude. Under an assumption of an exponential probability model that has several desirable properties...

A new method to measure the internal magnetic field in a plasma, based on crosscorrelation of ordinary (O) mode and extraordinary (X) mode reflectometer signals originating from naturally occurring turbulence, is investigated. This method relies on identifying the Oand X-mode frequency pair (fo, fx) where cross-correlation is maximum. Maximum cross-correlation is found to occur at an X-mode fre...

Various researchers have shown that accurate redatuming of controlled seismic sources to downhole receiver locations can be achieved without requiring a velocity model. By placing receivers in a horizontal or deviated well and turning them into virtual sources, accurate images can be obtained even below a complex near-subsurface. Examples include controlled-source interferometry and the virtual...

Latent feature models are attractive for image modeling, since images generally contain multiple objects. However, many latent feature models ignore that objects can appear at different locations or require pre-segmentation of images. While the transformed Indian buffet process (tIBP) provides a method for modeling transformation-invariant features in unsegmented binary images, its current form...