Biofeedback systems have been extensively used in walking exercises for gait improvement. Past research has focused on modulating the wearer's cadence, gait variability, or symmetry, but none of the previous works has addressed the problem of inducing a desired walking speed in the wearer. In this paper, we present a new, minimally obtrusive wearable biofeedback system (WBS) that uses closed-loop vibrotactile control to elicit desired changes in the wearer's walking speed, based on the predicted user response to anticipatory and delayed feedback.
View Article and Find Full Text PDFPhotoluminescence (PL) from Si and SiGe is comprehensively modified by Au NPs under excitation without surface plasmon resonance. Moreover, the PL sensitively depends on the size of the Au NPs, the excitation power and the thickness of the Si layer between the Au NPs and SiGe. A model is proposed in terms of the electrostatic effects of Au NPs naturally charged by electron transfer through the nanoscale metal/semiconductor Schottky junction without an external bias or external injection of carriers.
View Article and Find Full Text PDFHigh-quality Ge nanostructures are obtained by molecular beam epitaxy of Ge on Si(001) substrates at 200 °C and ex situ annealing at 400 °C. Their structural properties are comprehensively characterized by atomic force microscopy, transmission electron microscopy and Raman spectroscopy. It is disclosed that they are almost defect free except for some defects at the Ge/Si interface and in the subsequent Si capping layer.
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