noise is one of the major hazardous occupational exposures and one of the occupations at risk is the transportation industry. however, few studies have measured and reported the amount of noise exposure in drivers. in this study, we evaluated noise exposure among the public transportation bus drivers of one major iranian city, kerman, southeast iran. eighty public transportation buses in the st...

Ideal binary time-frequency masking is a signal separation technique that retains mixture energy in time-frequency units where local signal-to-noise ratio exceeds a certain threshold and rejects mixture energy in other time-frequency units. Two experiments were designed to assess the effects of ideal binary masking on speech intelligibility of both normal-hearing (NH) and hearing-impaired (HI) ...

This paper presents a new hidden Markov model-based (HMM-based) speech enhancement framework based on the independent component analysis (ICA). We propose analytical procedures for training clean speech and noise models by the Baum re-estimation algorithm and present a Maximum a posterior (MAP) estimator based on Laplace-Gaussian (for clean speech and noise respectively) combination in the HMM ...

Many hearing-impaired listeners struggle to localize sounds due to poor availability of binaural cues. Listeners with a cochlear implant and a contralateral hearing aid - so-called bimodal listeners - are amongst the worst performers, as both interaural time and level differences are poorly transmitted. We present a new method to enhance head shadow in the low frequencies. Head shadow enhanceme...

Speech reception thresholds (SRTs) for a target voice on the same virtual table were measured in various restaurant simulations under conditions of masking by between one and eight interferers at other tables. Results for different levels of reverberation and different simulation techniques were qualitatively similar. SRTs increased steeply with the number of interferers, reflecting progressive...

Recent psychophysical studies suggest that human listeners do not segregate concurrent sounds by grouping frequency regions that have a common interaural time difference (ITD). However, such an approach is adopted by most computational auditory scene analysis (CASA) systems that use binaural cues. Here, we propose a CASA system that separates a target speech signal from a noise interferer, but ...

Recent psychophysical studies suggest that human listeners do not segregate concurrent sounds by grouping frequency regions that have a common interaural time difference (ITD). However, such an approach is adopted by most computational auditory scene analysis (CASA) systems that use binaural cues. Here, we propose a CASA system that separates a target speech signal from a noise interferer, but ...

The ability to recognize masked speech, commonly measured with a speech reception threshold (SRT) test, is associated with cognitive processing abilities. Two cognitive factors frequently assessed in speech recognition research are the capacity of working memory (WM), measured by means of a reading span (Rspan) or listening span (Lspan) test, and the ability to read masked text (linguistic clos...

OBJECTIVE To evaluate monaural beamforming in bimodally aided cochlear implant (CI) users. DESIGN The study enrolled twelve adult bimodal listeners with at least six months of CI-experience and using a contralateral hearing aid (HA) most of the daytime. Participants were uniformly fitted with the same CI speech processor and HA, giving access to an identical monaural beamformer in both ears. ...