• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1191-1196
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• 2007

This research presents a laboratory study about an annoyance of impulsive sound caused by construction site(breaker and blasting). The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of jury test adopted a Semantic Difference Method (SDM). In the result of the Jury test for impulsive noise, the annoyance response of blasting noise was higher than that of breaker noise.

• KIEAE Journal
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• v.9 no.1
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• pp.61-68
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• 2009

In this study, computer simulation program was using to identify the effects of road traffic noise propagation depending on the road types which are very variable in dense city. To achieve this goal, the roads should adjacent to housing complex were categorized into 7 types and propagation noise level should predicted then after simulation of noise exposure population calculation are carried out. Followings the results. First, the road types producing the higher noise level are R1, R2, R3 and R7. The lowest one is R6. And R4, R5 showed that some amount of noise level reduction. Second. the R6 road type which is tunnel shaped showed the highest noise level reduction in vertical distance gap. Last, the order of noise exposure population ratio is R1>R2>R7 and R6 showed the lowest.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.523-527
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• 2007

Previous studies reported that exposure to noise during pregnancy adversely influenced the development of the fetus and neonate. In Oriental medicine, medications based on Angelicae gigantis radix have been known to be of efficacy in the treatment of various diseases. c-Fos, an immediate early gene whose expression is sometimes used as a marker for stimulus-induced changes in the metabolic activity of neurons. In the present study, the influence of postnatal Angelicae gigantis radix administration on c-Fos expression in the each region of hippocampus of offspring rats with prenatal noise stress during pregnancy was investigated. From the present results, exposure to the prenatal stress during pregnancy enhanced c-Fox expression, whereas exposure to postnatal Angelice gigantis radix suppressed c-Fos expression in the offsprings with prenatal noise stress during pregnancy. Based on the present study, Angelicae gigantis radix may provide new therapeutic opportunities as an agent to counteract the effects of prenatal noise stress- induced hippocampal dysfunction, and may be useful in the treatment of psychiatric problems in children of mothers who have experienced noise stress during pregnancy.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.9
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• pp.928-934
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• 2009

Underwater impulsive sound such as underwater blasting noise, piling noise and stone breaking hammer affects marine animal hearing response and organs. This study describes the characteristics of various impulsive noise from waterfront construction site and their effect on fish. Time constant, peak pressure, energy and SEL(sound exposure level) of four different underwater impulsive sounds are quantified. Auditory and non-auditory tissue damage ranges are derived by comparing their quantities to the exposure criteria for fish. Damage ranges of auditory tissue and non-auditory tissue of underwater boring blast of 150 kg of charge, are about 100 m and 300 m, respectively. Other three impulsive sounds also gives damage effects but less than that of underwater boring blast.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.433-438
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• 2001

This study is performed to evaluate hand-arm vibration syndrome(HA VS) of the workers in swaging process. Vibration measurement and assessment of human exposure are based on the international standard(ISO 5349). Triaxial acceleration of each operation and exposure time are measured to predict the periods before finger blanching, As results, it is found that acceleration is concerned with the diameter of pipes in swaging process, and also found that combined work is more harmful than a single operation.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4E
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• pp.58-64
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• 1996

The aims of this study were to investigate the covariation between the extent of activity disturbances and general annoyance, and to study the relation between the extent of annoyance reactions and noise sensitivity. This paper presents a description of a model developed by taking into account self-rated noise sensitivity and noise rating(i,e., annoyance) for road traffic. The results indicate that there are large variations in noise sensitivity which is independent on the level of noise. It is also found that the extent of all activity disturbances decreased with decreased general annoyance. The paper suggests a normative approach to predicting individual's reaction to noise exposure, based on a periodically observed relationship between the prevalence of activity disturbance and annoyance. The model also predicts a road traffic-noise adaptatin level for each individual.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.739-744
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• 2013

The aim of this study is to evaluate the noise level from the machines used for tunnel construction and to analyze the noise exposure level of workers engaged in tunneling works. The sound level meter and noise dosimeters was used for the monitoring of noise in the tunneling work sites. The average noise from jumbo drill was 113.0 dE(A), the noise from pay loader was 92.4 dB(A), the noise from backhoe was 99.9 dB(A) and the noise from shotcrete machine was 94.3 dE(A). The tunneling workers were exposed to 66.9~94.9 dB(A) of noise and other workers exposed to less than 90 dB(A) of noise. Jumbo drill operators were exposed to to 82.5~84.2 dB(A) of noise, backhoe operators were exposed to 70.2~94.9 dB(A) of noise, shotcrete machine operators were exposed to 68.2~74.7 dB(A) of noise and pay loader operators were exposed to 59.2~81.3 dE(A) of noise.

• Journal of Preventive Medicine and Public Health
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• v.24 no.4 s.36
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• pp.496-506
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• 1991

A cross-sectional study was conducted to investigate the effect of long term noise exposure on blood pressure among steel mill workers. The workers participated in periodic medical examinations performed from August 27 to September 6 in 1990. Examined were 1,034 workers with high-level noise exposure(average $91.8{\pm}5.2dB(A)$) and 390 workers with low-level noise exposure(average $75.2{\pm}4.6dB(A)$). No significant difference was found in systolic or diastolic flood pressure between the two exposure groups. Prevalence of hypertension (${\geq}160mmHg\;systolic\;or{\geq}100mmHg\;diastolic$) was higher in a younger age group (${\leq}40$ years old) of high-level noise exposure than of low-level noise exposure. However, the difference was not statistically significant. Furthermore, in younger ages, prevalence of hypertension appeared to be higher in the hearing loss group (${\geq}25dB\;at\;1000Hz\;or{\geq}40dB$ at 4000Hz in at least one ear) than in the normal hearing group. From multiple regression analysis, hearing loss, body mass index, age, alcohol and family history of hypertension were proven to be predictors of diastolic blood Pressure (p<0.02). When regression was performed for each age group, hearing loss was a strong predictor of diastolic pressure in the younger age group (p<0.01).

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.3 s.26
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• pp.193-199
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• 2006

The noise levels on board ship recognized at Europe in the early 1970s and the noise regulations on the ship began to put in a statutory form. After that, in 1982 'International Code on Noise Levels on Board Ships' adopted by IMO and it became a standards to the newly built ship and it remains up to recently. Especially, the ship engine room, which have huge main engine and various kinds of subsidiary machines, is under an extremely loud condition and so the worker who works in it is easy to lose his hearing. Recently, each nation regulates the allowable noise exposure time by law to protect the industrial employee from the occupational hardness of hearing. In our country, the allowable noise exposure time is regulated by the labor. standard law but the international provisions regulated by IMO have been applied in case of the ship engine room. In this paper, the cabin's noise levels of cargo-passenger ships plies south-west coast line were investigated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.714-720
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• 2008

This research presents a laboratory study about an subjective response of impulsive sound caused by leisure shooting. The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of the jury test adopted a Semantic Difference(SD) Method. In the result of the jury test for impulsive noise, the mean response rating expressed a linear relation and %HA(percent highly annoyed) displayed a exponential growth relation.