• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.421-424
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• 2008

This paper proposes an adaptive noise suppression system based on human auditory model to enhance speech signal that is degraded by various background noises. The proposed system detects voiced and unvoiced sections for each frame and implements the adaptive auditory process, then reduces the noise speech signal using neural network including amplitude component and phase component. Base on measuring signal-to-noise ratios, experiments confirm that the proposed system is effective for speech signal that is degraded by various noises.

• Speech Sciences
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• v.2
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• pp.125-134
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• 1997

Human beings can perceive various aspects of sound including loudness, pitch, length, and timber. Recently many studies were conducted to clarify complex auditory scales of the human ear. This study critically reviews some of these scales (decibel, sone, phon for loudness perception; mel and bark for pitch) and proposes to apply the scales to normalize acoustic correlates of human speech. One of the most important aspects of human auditory perception is the nonlinearity which should be incorporated into the linear speech analysis and synthesis system. Further studies using more sophisticated equipment are desirable to refine these scales, through the analysis of human auditory perception of complex tones or speech. This will lead scientists to develop better speech recognition and synthesis devices.

• Electronics and Telecommunications Trends
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• v.8 no.2
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• pp.69-91
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• 1993

In the conventional speech processing, the technique of FFT(Fast Fourier Transform) is usually applied to the finite number of samples within the window of specified length using the fixed sampling rate. In this case, the temporal resolution is dependent upon the length of window while the spectral resolution is dependent upon the number of samples within the window. Thus, once the temporal resolution is determined the spectral resolution is also determined or vice versa. To resolve this type of dilemma, a new type of bank-filter similar to the characteristics of cochlear model needs to be considered. Furthermore, wide dynamic range of cochlea certainly helps the stable extraction of speech features. In the paper, the human auditory system will be briefly introduced and previous works on auditory preprocessors based on cochlear model will be reviewed. As a conclusion, the design considerations of auditory preprocessors based on cochlear model will be addressed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.535-538
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• 2005

The purpose of this work is to study a process organization on space cognition by visio-auditory stimulation. We develop the system of visuo-auditory stimulation and Humans responses measurement to observe the relationship between the sensory and the motor system fur the localization of visual and auditory target direction in the space. The experiments is performed in a soundproof chamber, 2163 red, green and yellow LED(Luminescent Diode, Brightness: $20cd/m^2$ 1 degree apart each other)arrayed in front of half-circle panel were used and 57 Speaker(5 degree apart each other) arrayed in the hidden of half-circle panel. Physiological parameters such as EOG (Electro-Oculography), head movement and their synergic control are measured by BIOPAC system and Optotrak Certus. This result shows that the response latency time of the perception motion in the center is laster than the periphery of panel. These results can be used in the study of characterizing the spatial cognition.

• Safety and Health at Work
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• v.8 no.4
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• pp.329-336
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• 2017

A review study was conducted to examine the adverse effects of styrene, styrene mixtures, or styrene and/or styrene mixtures and noise on the auditory system in humans employed in occupational settings. The search included peer-reviewed articles published in English language involving human volunteers spanning a 25-year period (1990-2015). Studies included peer review journals, caseecontrol studies, and case reports. Animal studies were excluded. An initial search identified 40 studies. After screening for inclusion, 13 studies were retrieved for full journal detail examination and review. As a whole, the results range from no to mild associations between styrene exposure and auditory dysfunction, noting relatively small sample sizes. However, four studies investigating styrene with other organic solvent mixtures and noise suggested combined exposures to both styrene organic solvent mixtures may be more ototoxic than exposure to noise alone. There is little literature examining the effect of styrene on auditory functioning in humans. Nonetheless, findings suggest public health professionals and policy makers should be made aware of the future research needs pertaining to hearing impairment and ototoxicity from styrene. It is recommended that chronic styrene-exposed individuals be routinely evaluated with a comprehensive audiological test battery to detect early signs of auditory dysfunction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.1 s.22
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• pp.11-16
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• 2005

A ship can be considered as a large human-machine system and the interaction between worker and system affects the work performance and its efficiency. In the bridge if a ship, there exist many auditory signals as well as visual signals. However, only a few studies have been performed related to human recognition to alarm systems in the bridge. In this study, auditory icons and abstract sounds are compared to find more effective means if alarm systems. The study result shows that auditory icons are recognized faster than n abstract sounds. The result is expected to be use as a basic data for developing performance criteria q auditory display inside bridge and for designing integrated ship bridge alarm system.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.7-12
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• 2005

A ship can be considered as a large human-machine system and the interaction between worker and system affects the work performed and its efficiency. Inside the bridge of a ship, there exist many auditory signals as well as visual signals. However, only a few studies have been performed related to human recognition to alarm systems in bridge. In this study, auditory icons and abstract sounds are compared to find more effective means of alarm systems. the study result shows tint auditory icons are recognized faster than abstract sounds. This result is expected to be used as a basic data for developing performance criteria of auditory display inside bridge and for designing integrated ship bridge alarm system.

• The Journal of the Acoustical Society of Korea
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• v.20 no.8
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• pp.81-87
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• 2001

The human auditory system is appropriate for the "constant Q"system. The STFT (Short Time Fourier Transform) is not suitable for the auditory perception model since it has constant bandwidth. In this paper, the CWT (continuous wavelet transform) is employed for the auditory filter model. In the CWT, the frequency resolution can be adjusted for auditory sensation models. The proposed CWT is applied to the modeling of the JNVF. In addition, other signal processing methods such as STFT, VER-FFT and VFR-STFT are discussed. Among these methods, the model of JNVF (Just Noticeable Variation in Frequency) by using the CWT fits in with the JNVF of auditory model although it requires quite a long time.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.652-657
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• 2009

This paper proposes an adaptive noise suppression system based on human auditory model to enhance speech signal that is degraded by various background noises. The proposed system detects voiced, unvoiced and silence sections for each frame and implements an adaptive auditory process, then reduces the noise speech signal using a neural network including amplitude component and phase component. Based on measuring signal-to-noise ratios, experiments confirm that the proposed system is effective for speech signal that is degraded by various noises.

• Journal of the Ergonomics Society of Korea
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• v.23 no.3
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• pp.89-99
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• 2004

A comprehensive psychophysical scaling system, multiple-modality magnitude estimation system (MMES) has been designed to measure subjective multidimensional human perception. Unlike paper-based magnitude estimation systems, the MMES has an additional auditory peripheral cue that varies with corresponding visual magnitude. As the simplest, purely psychological case, bimodal divided-attention conditions were simulated to establish the superiority of the MMES. Subjects were given brief presentations of pairs of simultaneous stimuli consisting of visual line-lengths and auditory white-noise levels. In the visual or auditory focused-attention conditions, only the line-lengths or the noise levels perceived should be reported respectively. On the other hand, in the divided-attention conditions, both the line-lengths and the noise levels should be reported. There were no significant differences among the different attention conditions. Human performance was better when the proportion of magnitude in stimulus pairs were identically presented. The additional auditory cues in the MMES improved the correlations between the magnitude of stimuli and MMES values in the divided-attention conditions.