The secondary instabilities in the wake of a circular cylinder with near-wake wire disturbances are investigated by using threedimensional (3D) direct numerical simulations (DNS). For one wire placed asymmetrical about the wake centreline and two wires placed symmetrical about the wake centreline, the secondary instabilities are found to be Mode C and Mode A, respectively. The existence of the ...

The transfer of momentum from an animal to fluid in its wake is fundamental to many swimming and flying modes of locomotion. Hence, properties of the wake are commonly studied in experiments to infer the magnitude and direction of locomotive forces. The determination of which wake properties are necessary and sufficient to empirically deduce swimming and flying forces is currently made ad hoc. ...

The flow field in the near wake region (up to six turbine diameters downstream) of a tidal current is strongly driven by combined device support structure and rotor. Accurate characterisation near-wake important, but it dominated highly turbulent, slow-moving fluid. At present, limited number research has been undertaken into for Vertical Axis Tidal Turbine (VATT) using Reynolds Averaged Navier...

Hypersonic blunt-body flowfields containing a mixture of continuum and nonequilibrium flow are investigated using a modular particle–continuum numerical method. The modular particle–continuum method solves the Navier–Stokes equations in near-equilibrium regions and uses the direct simulation Monte Carlo method in nonequilibriumregions.Hypersonicflowof nitrogen over a two-dimensional cylinder at...

An artificial neural network, based on fuzzy ARTMAP, that is capable of learning the basic nonlinear dynamics of a turbulent velocity field is presented. The neural system is capable of generating a detailed multipoint time record with the same structural characteristics and basic statistics as those of the original instantaneous velocity field used for training. The good performance of the pro...

Many recent studies indicate that acetylcholine (ACh) in the brainstem is involved in REM sleep generation. Local ACh release in the brainstem regions, responsible for REM sleep during sleep and wakefulness, has not so far been reported because of technical difficulties. With in vivo microdialysis and electrochemical detection, we investigated the relationship between ACh release and sleep-wake...

We propose an approach to support massively multiplayer online games on a peer-to-peer system. Our approach is based on the fact that players are more interested in their region of visibility and influence than in the other regions. We use a computational geometry technique – Voronoi Diagram – to partition the game space into regions. The Voronoi partitioning gives some good closeness and local...

background: premature birth is a major cause of infant mortality in developed countries. newborns confined to neonatal intensive care units (nicus) are in a rapid stage of brain development. as such, sleep plays a pivotal role in the proper brain development of newborns. however, this developmental aspect is often disregarded due to the lack of information. aim: this study aimed to evaluate the...

Unphysical heating and macroparticle trapping that arise in the numerical modeling of laser wakefield accelerators using particle-in-cell codes are investigated. A dark current free laser wakefield accelerator stage, in which no trapping of background plasma electrons into the plasma wave should occur, and a highly nonlinear cavitated wake with self-trapping, are modeled. Numerical errors can l...