In this paper a new macroscopic k-ε model is developed and validated for turbulent flow through porous media for a wide range of porosities. The morphology of porous media is simulated by a periodic array of square cylinders. In the first step, calculations based on microscopic v2 − f model are conducted using a Galerkin/Least-Squares finite element formulation, employing equalorder bilinear ve...

Purpose: The present study aimed to determine the effect of dual-tasking on spatiotemporal characteristics in subjects with and without Anterior Cruciate Ligament Deficiency (ACLD) using linear dynamics. Methods: In this mixed model design study, spatiotemporal parameters were measured in 22 patients with ACLD (25.95±4.69 y) and 22 control subjects (24.32±3.37 y) while they were walking w...

hydrological drought refers to a persistently low discharge and volume of water in streams and reservoirs, lasting months or years. hydrological drought is a natural phenomenon, but it may be exacerbated by human activities. hydrological droughts are usually related to meteorological droughts, and their recurrence interval varies accordingly. this study pursues to identify a stochastic model (o...

Simulation is defined as the imitation of the operation of a system or real-world process over time, and in many cases, manufacturing provides one of the most important applications of simulation (Zolfaghari and Roa, 2006). Standard interfaces could make information effective sharing, and hence promote the utilization of simulators. An information model (McLean et al., 2005), which represents m...

The traditional worms such as Blaster, Code Red, Slammer and Sasser, are still infecting vulnerable machines on the internet. They will remain as significant threats due to their fast spreading nature on the internet. Various traditional worms attack pattern has been analyzed from various logs at different OSI layers such as victim logs, attacker logs and IDS alert log. These worms attack patte...

{ We develop a framework (employing scaling functions) for the construction of multi-step quasi-Newton methods (for unconstrained optimization) which utilize values of the objective function. The methods are constructed via interpolants of the m + 1 most recent iterates / gradient evaluations, and possess a free parameter which introduces an additional degree of exibility. This permits the inte...

Nonlinear Model Predictive Control (NMPC) has gained wide attention through the application of dynamic optimization. However, this approach is susceptible to computational delay, especially if the optimization problem cannot be solved within one sampling time. In this paper we propose an advanced-multi-step NMPC (amsNMPC) method based on nonlinear programming (NLP) and NLP sensitivity. This met...

We consider a simple model for the growth of isolated steps on a vicinal crystal surface. It incorporates diffusion and drift of adatoms on the terrace, and strong step and kink edge barriers. Using a combination of analytic methods and Monte Carlo simulations, we study the morphology of growing steps in detail. In particular, under typical Molecular Beam Epitaxy conditions the step morphology ...

We investigate the properties of the host galaxies of X–ray selected (high frequency peaked) BL Lac objects using a large and homogeneous data set of high spatial resolution R–band observations of 52 BL Lacs in the EMSS and Slew samples. The redshift distribution of the BL Lacs ranges from z = 0.04 to z>0.7, with average and median redshifts z = 0.26 and z = 0.24, respectively. Eight objects ar...

Cosmological numerical simulations of galaxy formation have led to the cuspy density profile of pure cold dark matter halo toward the center, which is in sharp contradiction with the observations of the rotation curves of cold dark matter-dominated dwarf and low surface brightness disk galaxies, the latter tends to favor mass profiles with a flat central core. Many efforts have been devoted to ...