Reaction wheels (RWs) used for attitude control of space vehicle systems usually encounter with undesired wide band noises. These noises which significantly affect the performance of regulator controller must tune the review or review rate of RWs. According to wide frequency band of noises in RWs the common approaches of noise cancellation cannot conveniently reduce the effects of the noise. Th...

Introduction: An efficient method of tomographic imaging in nuclear medicine is positron emission tomography (PET). Compared to SPECT, PET has the advantages of higher levels of sensitivity, spatial resolution and more accurate quantification. However, high noise levels in the image limit its diagnostic utility. Noise removal in nuclear medicine is traditionally based on Fourier decomposition o...

in order to the enhancement of the quality of speech corrupted by additive noise, a speech enhancement method has been put forward based on the combination of spectral subtraction and binary masking. spectral subtraction is a powerful method for removing noise from speech and binary masking provides essential elements to be used in monaural speech segregation. in the proposed combined method, f...

background: noise is one of the most pervasive hazards in industrial settings. this retrospective study was carried out to assess the effects of noise exposure on hearing status, blood lipids and blood pressure of employees of a local fireclay mine. methods: two hundred and forty male workers were studied. data on audiometric measurements, blood lipids and blood pressure were derived from the w...

in this paper some new applications of empirical mode decomposition (emd) and hilbert spectrum in seismic ground-roll attenuation, random noise attenuation and spectral decomposition are introduced. hilbert spectrum is a time-frequency representation for hilbert-huang transform which is obtained by combination of instantaneous frequency (if) concept and intrinsic mode function of empirical mode...

noise is considered as one of the harmful factors at industrial environments. it affects human health in different aspects including harmful influences on auditory, vision, neurological and psychiatric systems, hormones, physiological and mental systems. paying attention to the importance of hormonal effects on human body seems to possess crucial importance. the aim of the present study is to i...