48,931 research outputs found
The Patriot Actâs Impact on the Governmentâs Ability to Conduct Electronic Surveillance of Ongoing Domestic Communications
Lunar exploration for water deposits by electrical methods
Lunar exploration for water deposits by electrical method
Transition from Ekman flow to Taylor vortex flow in superfluid helium
By numerically computing the steady axisymmetric flow of helium II confined
inside a finite aspect ratio Couette annulus, we determine the transition from
Ekman flow to Taylor vortex flow as a function of temperature and aspect
ratio.We find that the low-Reynolds number flow is quite different to that of a
classical fluid, particularly at lower temperatures.At high aspect ratio our
results confirm the existing linear stability theory of the onset of Taylor
vortices, which assumes infinitely long cylinders.Comment: 12 pages, 8 figures; submitte
A novel drifter designed for use with a mounted Acoustic Doppler Current Profiler in shallow environments
We present a novel design for a surface drifter, mounted with a pulse-coherent Acoustic Doppler Current Profiler (ADCP) for measuring near-surface (depths 0.18-1 m) flows. During repeated drifter deployments over the tidal flats of Skagit Bay, the mounted ADCP recorded high quality and high resolution profiles of velocity in depths as shallow as 0.4 m. Depth-dependent velocities revealed regions of vertically sheared currents and wave motions not resolved by surface drifters alone. Although the cost of ADCPs is substantial, the drifter bodies were low cost, robust, and of simple construction
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