High accuracy attitude and position determination is very important for underwater gliders. The cross-coupling among three attitude angles (heading angle, pitch angle and roll angle) becomes more serious when pitch or roll motion occurs. This cross-coupling makes attitude angles inaccurate or even erroneous. Therefore, the high accuracy attitude and position determination becomes a difficult pr...

Details of pressure distributions, on a two dimensional airfoil oscillating in pitch through stall, in a 0.8 0.8 m low-speed wind tunnel are presented. Pitching occurred about the airfoils quarter-chord axis. Pitch rate, Reynolds number, and oscillation amplitudes were varied to determine the effects on pressure and lift distributions. It was found that mean angle of attack and pitching amplitu...

With the advent of high-speed and parallel computing, applicability computational optimization in engineering problems has increased, with greater validation than conventional methods. Pitch angle is an effective variable extracting maximum wind power a turbine system (WTS). The pitch controller contributes to improve output at different speeds. In this paper, proportional (P) proportional-inte...

[1] Suprathermal electrons (>70 eV) form a small fraction of the total solar wind electron density but serve as valuable tracers of heliospheric magnetic field topology. Their usefulness as tracers of magnetic loops with both feet rooted on the Sun, however, most likely fades as the loops expand beyond some distance owing to scattering. As a first step toward quantifying that distance, we const...

Helical ribbons with pitch angles of either 11 degrees or 54 degrees self-assemble in a wide variety of quaternary surfactant-phospholipid/fatty acid-sterol-water systems. By elastically deforming these helices, we examined their response to uniaxial forces. Under sufficient tension, a low pitch helix reversibly separates into a straight domain with a pitch angle of 90 degrees and a helical dom...

It is difficult for the deafblind or the hearing impaired to control the pitch of their voice, because they cannot perceive it. In particular, it is very difficult for them to control their voice pitch when singing, because they need to maintain a stable tone. We have developed a voice pitch control system to assist their singing by means of a tactile display. In a previous study, two deafblind...

The nonlinear resonant interaction of intense whistler-mode waves and energetic electrons in the Earth's radiation belts is traditionally described by theoretical models based on consideration slow–fast systems. Such reduce electron dynamics around resonance to single pendulum equation that provides solutions for scattering (phase bunching) phase trapping. Applicability this approach limited no...

Wind turbine employs pitch angle control to maintain captured power at its rated value when the wind speed is higher than value. This work adopts a perturbation observer based sliding-mode (POSMC) strategy realize robust variable-pitch of permanent magnet synchronous generator (PMSG). POSMC combines system nonlinearities, parametric uncertainties, unmodelled dynamics, and time-varying external ...