This paper proposes an improved optical flow estimation approach based on the total variational L1 minimization technique with weighted median filter. Furthermore, recovering image details using modified census transform algorithm improves the overall accuracy of estimating large scale displacements optical flow. On the other hand, the use of the Taylor expansion approximation in most of the op...

Our long-term scientific goal is to develop sound theoretical models for submarine sediment movement that can be used to predict the initiation, spatial development, and time duration of mud flows and turbidity currents. Of great interest are the characteristics of the sedimentary deposits that these flows generate, in particular their capability to develop bed forms and gullies by means of sed...

a molecular model at multiscale for human platelets is designed and implemented on large-scale supercomputers. The model characterizes the principal physiological functions of key components of single platelet. The organelle zone centralizes as the cytoplasm, the peripheral zone includes the bilayer and exterior coats, and the cytoskeleton zone forms the flow-induced filopodia. It is the first ...

Rapid shallow granular free-surface flows develop in a wide range of industrial and geophysical flows, ranging from rotating kilns and blenders to rock-falls, snow slab-avalanches and debris-flows. Within these flows, grains of different sizes often separate out into inversely graded layers, with the large particles on top of the fines, by a process called kinetic sieving. In this paper, a rece...

Granular flows comprise a wide range of particle sizes. The particle size governs the degree of grain contact and inertial stresses in the flow, thus influencing the mechanism of impact against a rigid barrier. The current commonly adopted design approaches estimating the run-up height are based on the energy principle and the momentum approach. However, both neglect the discrete nature of flow...

We develop a class of V-cycle type multilevel restricted additive Schwarz (RAS) methods and study the numerical and parallel performance of the new fully coupled methods for solving large sparse Jacobian systems arising from the discretization of some optimization problems constrained by nonlinear partial differential equations. Straightforward extensions of the one-level RAS to multilevel do n...

In this paper we study some nonoverlapping domain decomposition methods for solving a class of elliptic problems arising from composite materials and flows in porous media which contain many spatial scales. Our preconditioner differs from traditional domain decomposition preconditioners by using a coarse solver which is adaptive to small scale heterogeneous features. While the convergence rate ...

This paper describes a framework to estimate global motion model based on B-spline wavelets. The wavelet-based model allows optical flow to be recovered at different resolution levels from image derivatives. By combining estimation from different resolution levels in a coarse to fine scheme, our algorithm is able to recover a large range of velocity magnitude. Our algorithm is evaluated on arti...

We present a two-scale finite element method for solving Brinkman’s equations with piece-wise constant coefficients. This system of equations model fluid flows in highly porous, heterogeneous media with complex topology of the heterogeneities. We make use of the recently proposed discontinuous Galerkin FEM for Stokes equations by Wang and Ye in [12] and the concept of subgrid approximation deve...