An axi-symmetric and swirling vortex sheet is investigated as the simplest ow in which there is non-trivial vortex stretching and as a possible setting for studying vortex cancellation and singularity formation. Rayleigh's criterion indicates linear stability of a single sheet but instability for other conngurations of sheets. Due to the simplicity of vortex sheet problems, the linear modes and...

Deception dectection is one of the most difficult problems in affect recognition and expression research area. Recently, non-verbal methods of detecting deception have appeared to be promising. Thomas[1] presented a proof-of-concept study based on the blob analysis of some suspects’ interviews and mock experiments video clips. In this paper, we present our recent research work in the direction ...

The method of radial velocities (RV) is applied to estimate aircraft wake vortex parameters from measurements conducted with pulsed coherent Doppler lidar (PCDL). Operations of the Stream Line lidar and the 2-µm PCDL are simulated numerically to analyze the accuracy of the estimated wake vortex parameters with the RV method. The RV method is also used to estimate wake vortex trajectories and ci...

We present an efficient and general method to compute vortex-pinning interactions--which arise in neutron stars, superconductors, and trapped cold atoms--at arbitrary separations using real-time dynamics. This method overcomes uncertainties associated with matter redistribution by the vortex position and the related choice of ensemble that plague the typical approach of comparing energy differe...

Abstract—In a previously developed fast vortex method, the diffusion of the vortex sheet induced at the solid wall by the no-slip boundary conditions was modeled according to the approximation solution of Koumoutsakos and converted into discrete blobs in the vicinity of the wall. This scheme had been successfully applied to a simulation of the flow induced with an impulsively initiated circular...

In the medical image annotation task we have mainly explored ways to use different image features to achieve robust classification performance, including both global features and regional blob features. Experimental results show that using a combination of the blob region feature and three low resolution pixel maps (gray level, texture and contrast) can achieve the highest recognition accuracy....

this paper is about experimental results for partial reduction of vortex at vertical pipe intakes. one of the easiest and practical ways of reducing vortex effect is to use anti-vortex plates or baffles. these plates can be used to avoid the vortex completely or partially. this paper will concentrate on the latter case. rectangular plates with different dimensions have been placed at different ...

The problem of incompressible steady flow simulation around an airfoil is discussed. For some simplest airfoils (circular, elliptical, Zhukovsky airfoils) the exact solution is known from complex analysis. It allows to compute the intensity of vortex layer which simulates the airfoil. Some modifications of the vortex element method are proposed and test computations are carried out. It’s shown ...

We compared the precision of perceptual localization and manual pointing. A Gaussian blob was presented 6 degrees to the right or left of a central fixation spot on a CRT screen. Above and below the blob, vertical lines were displayed. On each trial, the blob was slightly offset to the right or left with respect to the lines. The subjects had to judge whether the blob appeared to the right or t...