The paper shows the results of the convective heat transfer prediction in turbulent axisymmetric jets impinging onto a flat plate using the newest version (2006) of the k-ω turbulence model of Wilcox [1]. Improvements to the heat transfer predictions are obtained in the strongly strained flow regions with the impingement invariant proposed by Manceau [2] together with the F1 function proposed b...

1 Abstract In this paper we discuss the dynamical features of intermittent fluctuations in homogeneous shear flow turbulence. In this flow the energy cascade is strongly modified by the production of turbulent kinetic energy related to the presence of vortical structures induced by the shear. By using direct numerical simulations, we show that the refined Kolmogorov similarity is broken and a n...

Using kinetic Monte Carlo simulations and a bond– counting ansatz, thermal stability and diffusion of an adatom island on a crystal surface are studied. At low temperatures, the diffusion constant D is found to decrease for a wide range of island sizes like D ∝ N−α, where α is close to one, N being the number of adatoms in the cluster. By heating up the surface, the system undergoes a phase tra...

A fast estimator is proposed and applied to the problem of range identification in the presence of unknown motion parameters. Assuming a rigid-body motion with unknown constant rotational parameters but known translational parameters, estimation of the unknown parameters is achieved by a fast estimator, followed by recursive least square extraction. The results are also extended to the case of ...

We propose a stochastic model for molecular transport at the nanoscale that describes the motion of two-dimensional molecular assemblies called multivalent random walkers (MVRWs). This walker model is an abstract description of the motion of multipedal molecular assemblies, called molecular spiders, which use deoxyribozyme legs to move over a surface covered with substrate DNA molecules, cleavi...

This paper illustrates a new optical flow estimation technique that builds upon a genetic algorithm (GA). First, the current frame is segmented into generic shape regions, using only luminance and color information. For each region, a two-parameter motion model is estimated using a GA. The fittest individuals identified at the end of this step are used to initialize the population of the second...

We have carried out long time scale simulations where the \dimer method" [G. Henkelman and H. J onsson, J. Chem. Phys. 111, 7010 (1999)] is used to nd the mechanism and estimate the rate of transitions within harmonic transition state theory and time is evolved by using the kinetic Monte Carlo method. Unlike traditional applications of kinetic Monte Carlo, the atoms are not assigned to lattice ...

We investigate the formation of misfit dislocations in strained heteroepitaxial crystal growth and their influence on the structure of the growing layers. We use Kinetic Monte Carlo simulations for an off-lattice model in 1+1 dimensions with Lennard-Jones interactions. Two different types of the formation of dislocations are found, depending on the sign and the magnitude of the misfit. Misfit d...

Multiscale schemes for transferring information from fine to coarse scales are typically based on homogenization techniques. Such schemes smooth the fine scale features of the underlying fields, often resulting in the inability to accurately retain the fine scale correlations. In addition, higher-order statistical moments (beyond mean) of the relevant field variables are not necessarily preserv...

We explore aspects of the community structures generated by a simple predator-prey model of biological coevolution, using large-scale kinetic Monte Carlo simulations. The model accounts for interspecies and intraspecies competition for resources, as well as adaptive foraging behavior. It produces a metastable low-diversity phase and a stable high-diversity phase. The structures and joint indegr...