Tail-biting trellises are defined on a circular time axis and can have a smaller number of states than equivalent conventional trellises. Existing circular Viterbi algorithms (CVAs) on the tail-biting trellis are non-convergent and sub-optimal. In this study, we show that the net path metric of each tail-biting path is lower-bounded during the decoding process of the CVA. This property can be a...

Making soap bubbles by blowing air on a soap film is an enjoyable activity, yet a poorly understood phenomenon. Working either with circular bubble wands or long-lived vertical soap films having an adjustable steady state thickness, we investigate the formation of such bubbles when a gas is blown through a nozzle onto a film. We vary film size, nozzle radius, space between the film and nozzle, ...

A method based on microjets is implemented to control the flow properties in a convergent-divergent nozzle undergoing sudden expansion. Three different variants of this active technique are explored numerically by means finite-volume for compressible fluid flow: with first one, at base, second wall, while third one may be regarded as combination other two variants. When jets over-expanded, not ...

Closed-form solutions have been derived for the diffraction patterns at the focal plane of (1) a convergent wave of unit amplitude illuminating a segment of a circular aperture and (2) a convergent wave of Gaussian amplitude diffracted by an infinite edge. Photographs showing the main features of these edge transform patterns are presented together with computer-generated graphs.

Abstract The following work documents the effect of streamwise vortices generated at the nozzle exit of an axisymmetric air jet on the amount of mass entrained into an ejector. In an experimental analysis of the mass entrainment of circular jet ejectors, we found that the introduction of half delta wing vortex generators in the exit of the jet nozzle (Reynolds number of 50,000) increased the am...

A laser-Doppler velocimeter suitable for the measurement of mean and fluctuating flow velocities in water is described. Results of a study using this system in an axisymmetric turbulent jet of water and dilute polymer solutions are given. The laser-Doppler technique is better suited for such measurements than either Pitot tubes or heat-transfer gauges because the Doppler velocity measurements a...