For an inverter-driven compressor, the discharge temperature increased with a rise of frequency. Therefore, it is necessary to control the discharge temperature at high frequencies in order to obtain system reliability and efficiency. This paper describes the effects of an injection system on the perfonnance of an inverter-driven scroll compressor. As results of the present work, the refrigeran...

Transient evoked otoacoustic emissions (TEOAEs) have been analyzed for objective assessment of hearing function and monitoring of the influence of noise exposure and ototoxic drugs. This paper presents a novel application of the Hilbert–Huang transform (HHT) for detection and time-frequency mapping of TEOAEs. Since the HHT does not distinguish between signal and noise, it is combined with ensem...

This paper presents a fast and effective algorithm for enhancing speech intelligibility in additive noise conditions under the constraint of equal signal power before and after enhancement. Speech energy is reallocated in time, using dynamic range compression, and in frequency by boosting the signal to noise ratio in high frequencies, increasing the contrast between consecutive spectral peaks a...