One month’s worth of POLAR UVI data were subjected to a ‘‘blob’’ analysis to determine the statistical dynamics of substorm features observed in the LBHL band (152-188 nm). Adapted from similar DoD analyses of target images, the analysis consists of finding, on a frame-by-frame basis beginning at substorm onset, the following aspects of an individual auroral feature: peak power (i.e., power of ...

Abstract   In this paper, we propose a new method for kernel based object tracking which tracks the complete non rigid object. Definition the union image blob and mapping it to a new representation which we named as potential pixels matrix are the main part of tracking algorithm. The union image blob is constructed by expanding the previous object region based on the histogram feature. The pote...

In this paper, using vortex blob method (VBM), turbulent flow in a channel is studied and physical concepts of turbulence are obtained and discussed. At first, time-averaged velocities,  and , and then their fluctuations are calculated. To clarify turbulence structures, velocity fluctuations and  are plotted. It is observed that turbulence structures occupy different positions and move with con...

As a counterpoint to classical stochastic particle methods for diffusion, we develop a deterministic particle method for linear and nonlinear diffusion. At first glance, deterministic particle methods are incompatible with diffusive partial differential equations since initial data given by sums of Dirac masses would be smoothed instantaneously: particles do not remain particles. Inspired by cl...

The binormal (or vortex filament) equation provides the localized induction approximation of 3D incompressible Euler equation. We present explicit solutions in higher-dimensions that collapse finite time. local nature this phenomenon suggests a possibility singularity appearance nearby blob 5D and higher. Furthermore, Hasimoto transform takes to NLS barotropic fluid equations. show higher dimen...

This research describes the unsteady two-dimensional reacting flows around a circular cylinder. The numerical solution combines the random vortex method for incompressible two-dimensional viscous fluid flow with a Simple Line Interface Calculation (SLIC) algorithm for the propagation of flame interface. To simplify the governing equations, two fundamental assumptions namely Low Mach Number and ...

The thermally activated vortex bundle flow over the directional-dependent energy barrier in type-II superconductors is investigated. The coherent oscillation frequency and the mean direction of the random collective pinning force of the vortex bundles are evaluated by applying the random walk theorem. The flow velocity of the vortex bundles is obtained self-consistently. The temperatureand fiel...

This DNS study is focused on the structure of turbulence in a boundary layer. First, it is not appropriate to call the turbulent flow as a “random” motion. Any mean flow like Blasius solution, which is a Navier-Stokes solution, added by white noise or random perturbation would be rejected by Navier-Stokes equations and the perturbation will be damped quickly. The governing Navier-Stokes equatio...

For thin films of superfluid adsorbed on a disordered substrate, we derive within a mean field (Hartree) description of the condensate the equation of motion for a vortex in the presence of a random potential. The compressible nature of the condensate leads to an effective pinning potential experienced by the vortex which is nonlocal, with a long range tail that smoothes out the random potentia...