An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audio...An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audiometric transducer such as an earphone. The calibrated sound intensities for an audio-logical examination can be obtained in terms of the sound pressure levels of pure-tonal sinusoidal signals in eight-banded frequency ranges (250, 500, 1 000, 2 000, 3 000, 4 000, 6 000 and 8 000 Hz), and with mapping of the input sound pressure levels by the weight coefficients that are tuned by the delta learning rule. With this scheme, the sound intensities, which evoke eight-banded sound pressure levels by 5 dB steps from a minimum of 25 dB to a maximum of 80 dB, can be generated without volume displacement. Consequently, these sound intensities can be utilized to accurately determine the hearing threshold of a subject in the ambulatory audiometric testing environment.展开更多
The audiometric zero level of air conduction for 100 healthy youths was determinedover a froequency range from 20 Hz to 10 KHz in 1971--1973 under the laboratory conditions.The results obtained have been further verif...The audiometric zero level of air conduction for 100 healthy youths was determinedover a froequency range from 20 Hz to 10 KHz in 1971--1973 under the laboratory conditions.The results obtained have been further verified recently on a selected group of 12 persons.This paper also presents the transfer experiments from the original earphone TDH-39(MX-41/AR) to six other types of earphones. The deviation of our data thus obtained from therecommendation by ISO is discussed.展开更多
The few studies evaluating the changes caused by cigarette smoking on hearing loss induced by occupational exposure to noise have reached discordant conclusions. The aim of this study is to investigate the interaction...The few studies evaluating the changes caused by cigarette smoking on hearing loss induced by occupational exposure to noise have reached discordant conclusions. The aim of this study is to investigate the interactions between cigarette smoking and occupational exposure to noise as risk factors in the onset and development of hearing loss. The study was performed on a sample of 557 shipyard workers exposed to noise at an Equivalent Level (Leq) of 93 dBA. On the basis of their smoking habits, they were divided into three groups: group (A), non-smokers;group (B), smokers (15-30 cigarettes per day);and group (C), heavy smokers (over 30 cigarettes per day). The study focussed on the audiometric responses of the subjects at the frequencies of 500, 1000, 2000, 3000 and 4000 Hz. The results were then compared using statistical techniquees (Internal correlation coefficient, exponential model, ANCOVA, NPC test). Comparison of the audiometric responses showed statistically significant differences between the three groups. Non-parametric analysis, performed using the NPC test, highlighted that the interaction between smoking and exposure to noise has an influence on hearing loss at all frequencies, and particularly at high frequencies (3000-4000 Hz). The data obtained from the examined sample show that smoking and exposure to noise cause an increase in occupational hearing loss and that this is directly related to the number of cigarettes smoked.展开更多
基金supported by the grant of the Korean Ministry of Education, Science and Technology (The Regional Core Research Program/Chungbuk BIT Research-Oriented University Consortium)
文摘An efficient calibration algorithm for an ambulatory audiometric test system is proposed. This system utilizes a personal digital assistant (PDA) device to generate the correct sound pressure level (SPL) from an audiometric transducer such as an earphone. The calibrated sound intensities for an audio-logical examination can be obtained in terms of the sound pressure levels of pure-tonal sinusoidal signals in eight-banded frequency ranges (250, 500, 1 000, 2 000, 3 000, 4 000, 6 000 and 8 000 Hz), and with mapping of the input sound pressure levels by the weight coefficients that are tuned by the delta learning rule. With this scheme, the sound intensities, which evoke eight-banded sound pressure levels by 5 dB steps from a minimum of 25 dB to a maximum of 80 dB, can be generated without volume displacement. Consequently, these sound intensities can be utilized to accurately determine the hearing threshold of a subject in the ambulatory audiometric testing environment.
文摘The audiometric zero level of air conduction for 100 healthy youths was determinedover a froequency range from 20 Hz to 10 KHz in 1971--1973 under the laboratory conditions.The results obtained have been further verified recently on a selected group of 12 persons.This paper also presents the transfer experiments from the original earphone TDH-39(MX-41/AR) to six other types of earphones. The deviation of our data thus obtained from therecommendation by ISO is discussed.
文摘The few studies evaluating the changes caused by cigarette smoking on hearing loss induced by occupational exposure to noise have reached discordant conclusions. The aim of this study is to investigate the interactions between cigarette smoking and occupational exposure to noise as risk factors in the onset and development of hearing loss. The study was performed on a sample of 557 shipyard workers exposed to noise at an Equivalent Level (Leq) of 93 dBA. On the basis of their smoking habits, they were divided into three groups: group (A), non-smokers;group (B), smokers (15-30 cigarettes per day);and group (C), heavy smokers (over 30 cigarettes per day). The study focussed on the audiometric responses of the subjects at the frequencies of 500, 1000, 2000, 3000 and 4000 Hz. The results were then compared using statistical techniquees (Internal correlation coefficient, exponential model, ANCOVA, NPC test). Comparison of the audiometric responses showed statistically significant differences between the three groups. Non-parametric analysis, performed using the NPC test, highlighted that the interaction between smoking and exposure to noise has an influence on hearing loss at all frequencies, and particularly at high frequencies (3000-4000 Hz). The data obtained from the examined sample show that smoking and exposure to noise cause an increase in occupational hearing loss and that this is directly related to the number of cigarettes smoked.
