Sharif Digital Repository

In this work, the rising of a single bubble in a quiescent liquid under microgravity condition was simulated. In addition to general studies of microgravity effects, the initiation of hydrodynamic convection, solely due to the variations of interface curvature (surface tension force) and thus the generation of shearing forces at the interfaces, was also studied. Then, the variation of surface tension due to the temperature gradient (Marangoni convection), which can initiate the onset of convection even in the absence of buoyancy, was studied. The related unsteady incompressible full Navier-Stokes equations were solved using a finite difference method with a structured staggered grid. The... 

Tracking vehicles across nonoverlapping cameras is required by video-based intelligent transportation systems (ITS) to efficiently calculate traffic parameters; such as link travel times and origin/destination counts. In traffic monitoring applications, cameras are usually mounted far from each other to cover wide areas. As such, object features (i.e., color information, shape, and direction) change significantly from one camera to another. These space-time differences raise serious challenges on efficient tracking. In this paper, we have presented a probabilistic model to solve the multicamera tracking task in a network of disjoint view cameras, with attention paid on estimating the density... 

This paper presents a novel and fast homography-based tracking method to segment and track the instructor placed in front of a class board using two synchronized views. In the proposed method we estimate the instructor as a planar object and track its planar parameters. At first, the homography of board and fundamental geometry of two views are extracted using six point correspondences. The homography transformation matrix of object is calculated by obtaining three point correspondences in parallax region introduced with homography of the board. The parameters to be tracked by Kalman filter are obtained frame by frame by object's homography decomposition. Our proposed method is robust...