background & aim : mother-infant separation is one of the main causes of sleep-wake states disorders in neonatal intensive care unit (nicu). the current study was conducted to investigate the effect of in-arms-holding by mothers on sleep-wake states disorders of preterm neonates. methods & materials : in a pilot study, through a semi-experimental pretest-posttest method, 35 preterm neonates wit...

The three-dimensional incompressible flow past a rectangular open cavity is investigated, where the aspect ratio of the cavity is considered as 4. The principle objective is to use large-eddy simulation to resolve and control the large-scale structures, which are largely responsible for flow oscillations in a cavity. The flow past an open cavity is very common in aerospace applications and can ...

The effect of a combined system of the bed suction and jet injection as a pier-scour countermeasure on the turbulent flow field is studied in a laboratory flume using an Acoustic Doppler Velocimeter (ADV). The three components of the velocities in the vertical symmetry plane in the equilibrium scour hole in front and rear of the pier under 3-jet injections and bed suction rate Qs/Q0 = 2%located...

In the present work, a numerical simulation of two parallel turbulent jets was performed. The simulations were carried out by using the  standard, the  standard and the RSM models. A parametric study was also presented to determine the effect of the nozzles spacing and velocity ratio on the axial and transverse positions of the merge and combined points. Correlations between the various paramet...

At present, there is no publicly published research on the unsteady interference effect in start-up process of lateral jet control spinning missile. The variation aerodynamic characteristics during missile still unclear. Therefore, numerical method based three-dimensional compressible Navier–Stokes equations and sliding mesh used to study starting jet. Based verification simulation this paper, ...

As the demand for the civil aviation has been growing for decades and the system becoming increasingly complex, the use of systems engineering and operations research tools have shown to be of further use in managing this system. In this study, we apply such tools in managing landing operations on runways (as the bottleneck and highly valuable resources of air transportation networks) to handle...

Two high-speed stereo PIV (HS-SPIV) systems have been used for the characterization of pulsed and continuous jet actuators in the turbulent boundary layer (TBL) wind tunnel at ONERA Lille, an Eiffel type wind tunnel in suction mode with a low turbulence level. The test aimed at generating an aerodynamic database useful for the characterisation of (unsteady) vortical structures responsible for t...

Numerical simulation has been performed by solving full Navier–Stokes equations governing the three-dimensional unsteady compressible flows. The main goal of the present work is to investigate the flow characteristics of a square jet issuing transversally into a cross-flow at three injection angles of 90°, 60° and 30°, and thus to provide some deeper insights into the physical flow mechanism go...

BACKGROUND To reduce the environmental impacts of the aviation sector as air traffic grows steadily, the aviation industry has paid increasing attention to bio-based alternative jet fuels (AJFs), which may provide lower life-cycle petroleum consumption and greenhouse gas (GHG) emissions than petroleum jet fuel. This study presents well-to-wake (WTWa) results for four emerging AJFs: ethanol-to-j...