• Journal of Environmental Impact Assessment
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• v.27 no.2
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• pp.105-113
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• 2018

The modeling of noise mapping and the evaluation of noise pollution based on the exposed population were frequently used as an indicator of environmental noise assessment to overcome the limitations of field survey and Tele-Monitoring System. Results from these methods were highly influenced by the setting of noise source, input data of prediction factors and analytical methods of predictive values. The population exposed to noise were estimated as M1-1>M2-1>Base>M2-2>M1-2 in both areas. The highest noise setting methods(M1-1, M1-2) were overestimated, being compared with the Base method.

• Journal of Preventive Medicine and Public Health
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• v.36 no.2
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• pp.137-146
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• 2003

Objectives : Impaired hearing is a prevalent occupational hazard, not only in industry, but also in the armed forces. In military life, noise has unusual characteristics, and constitutes a serious hazard to hearing. The aim of this study was to analyze the hearing threshold data in order to compare the hearing loss among shipyard workers, representing different workers, and a military service background. Methods : A cross-sectional audiological survey, combined with a questionnaire study, was conducted on a stratified random sample of 440 shipyard workers, with long-term exposure to noise. The employees were divided into four groups, according to their working and military service backgrounds, in relation to their exposure to noise. Results : As expected, the working and military noise exposure group (Group I) had significantly poorer hearing than the other groups. The high frequencies (2-8 kHz) showed the greatest difference in terms of poorer fearing in both ears. The prevalence of noise-induced hearing loss (NIHL) was highest in Group I. A logistic regression analysis was applied to determine the dependence of the NIHL in relation to age, smoking, drinking, working duration, ear protection, past history of ear diseases, and working and military sonics backgrounds, on the noise exposure The important factors found to be related to the NIHL, in relation to noise exposure were: age, work duration, and working and military service backgrounds. The adjusted odds ratio estimates for NIML in the right ear were 4.5 times greater (95% CI 1.7-11.6) for the military noise exposed group, and 7.9 times greater (95% CI 2.0-31.3) for the working noise exposed group than in the controls. The hearing thresholds at the pure-tone average and 4 kHz were significantly increased with age and work duration with both the working and military service backgrounds. Conclusions : From these results, specific preventive programs were planned, which should be assessed by epidemiological surveillance of the military noise exposed population.

• Science of Emotion and Sensibility
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• v.2 no.1
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• pp.137-145
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• 1999

열 두 명의 피험자가 안정상태 일 때, 백색 소음에 노출되었을 때, 백색 소음 하에서 기억과제에 주의를 기울일 때, 백색 소음 하에서 기억 검사를 받을 때, 기록된 뇌파에 대해 relative power spectrum 분석을 하였다. 뇌파는 전두, 측두, 후두 영역에서 단극 유도법으로 기록되었다. 분석 결과, 백색 소음에만 노출되었을 때나, 백색 소음 하에서 기억과제에 주의를 기울일 때나 비슷한 전기피질(electrocortical) 반응이 나타났다. 즉, delta power의 증가, 알파 blocking, fast beta power의 증가, 스트레스를 일으킨다고 피험자들이 평정한 배색 소음 하에서 기억검사를 받을 때에도 동일한 뇌파 패턴이 나타났지만 그 크기가 유의하게 컸다. 정보를 지각할 때 전형적으로 나타나는 반응을 유발하는 스트레스원에 수동적으로 노출되었을 때("intaki"상황)의 생리 반응과 스트레스 상황에 적극적으로 대처할 때("rejection")의 생리 반응을 구분하는 이론 틀 아래서 데이터를 해석하였다. 스트레스 후 기간에 대부분의 뇌파 변수들이 기저선 수준으로 회복된 것으로 보아 사용한 스트레스 유발 모델은 단기적 스트레스 반응만을 유발한 것으로 보인다. 이는, 더 장기적으로 지속되는 스트레스원을 사용하게 되면, tonic상태의 전기피질 반응이 나타날 것을 시사한다.기피질 반응이 나타날 것을 시사한다.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.179-185
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• 1997

작업장 뿐만 아니라 일상생활에서도 결코 무시될 수 없는 것이 레져활동으로 인한 소음이다. 최근 급격히 늘어가는 개인 휴대용 카세트(Personal Cassette Players: PCP)사용은 심각한 소음성난청 발생이 우려된다. 본 연구는 PCP사용에 관련된 여러 인자들이 청력손실과 어떻게 얼마나 관련이 있는가를 파악 하고 PCP를 일정시간 사용했을 때 오는 청력 손실을 정량적으로 파악, 분석하는데 근본 목적을 둔다. 정상 청력을 가진 피실험자 18명의 대학생들을 대상으로 정상 청취조건 그리고 배경소음(지하철)에 노출 중과 후의 사용환경과 소음원으로 Hard Music, Soft Music 및 Language/News를 고려하여 평균소음도와 최고 소음도를 측정하였다. 또한 현실적 상황을 고려한 2시간 정도의 PCP의 청취 전과 후의 청력변화를 측정하였다. 통계 분석 결과, 사용환경과 소음원에 대해 휴대용 카세트 청취 소음수준이 유의한 차이가 있었으며, 특히 Hard Music 청취시에는 95dB, 그리고 지하철 소음하에서는 92dB의 높은 (위험한) 청취수 준을 보였다. 최고소음수준의 경우 NIOSH기준을 초과하는 117dB 정도의 매우 위험한 수준까지 나타났다. 또한 2 시간 정도의 PCP소음에 노출 전 후의 청력손실이 주파수 대역에 걸쳐 유의하게 나타났으며, 특히, 가장 민감한 주파수 대역인 4000Hz에서 최고 7dB 정도의 청력 손실이 발생하였다. 본 연구 결과에 따라, PCP사용에 대한 청력보호대책안을 제시하고자 한다.

• Journal of the Korean association of regional geographers
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• v.19 no.3
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• pp.541-550
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• 2013

Noise is defined to be unwanted (or undesirable) sounds, and it can be subdivided into occupational and environmental noises. The occupational noise is largely emitted from workplaces, but the environmental noise is produced from various sources such as transportation, construction, and even neighborhood. Transportation, particularly road vehicles, has been recognized to play a major role in emitting environmental noise and having adverse effects on urban communities. Considering this issue, this research investigated how severe the impacts of road traffic noise on a variety of land uses in a highly urbanized area, Fulton County, Georgia, United States. Daytime and nighttime road traffic noise maps were derived with Traffic Noise Model that was developed by Federal Highway Administration at United States Department of Transportation. Individual noise maps were overlaid on three-tiered land use type maps in order to evaluate the magnitude of noise impacts on the study area, as a noise exposure assessment. This study found that many land use parcels and buildings were exposed to noise levels exceeding the guideline values of the World Health Organization and the Atlanta Code of Ordinance. Therefore, it would be required to take an action that can protect many urban residents from ill effects of road traffic noise.

• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.348-357
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• 2020

An important challenge in commercialization of eVTOL PAV is to reduce noise for urban air mobility (UAM) operation. Therefore, in this paper, noise priority routes were created to minimize the number of people affected by noise using aviation environmental design tool (AEDT) software and population distribution data for administrative districts, and noise analyses during operation were performed. Also, it was analyzed how much noise exposure could be reduced compared to the number of people affected by noise in the shortest route. Considering that the eVTOL PAV developers do not provide data, the analysis was conducted using a helicopter model. As a result, it was shown that the noise priority route that minimized the amount of noise exposure was more efficient than other routes.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.148-149
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• 2010

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.577-578
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• 2013

• The Journal of the Acoustical Society of Korea
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• v.34 no.4
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• pp.274-281
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• 2015

Although noise-induced hearing loss (NIHL) is a significant public health problem, many people might not be aware that exposure to loud noise could occur hearing loss. The purpose of this study is to evaluate and analyze how importantly and seriously people are aware of NIHL using a 22-question survey. It was administered to random 150 people including between 20 s to 60 s. The questionnaire contained questions about i) views toward general health issues including hearing loss and tinnitus, ii) noise exposure, and iii) views toward hearing protection. Results showed that hearing loss was defined on a likert scale as 'a very big problem' by 17.33 % of respondents compared with other health issues. Surprisingly, most respondents (82 %) had not heard, read, or seen anything lately related to the issue of hearing loss. Many respondents had experience hearing problem or tinnitus under loud noise situations (85 %), however, only 11.33 % of respondents had used earplugs. Fortunately, many could be motivated to try ear protection if they were advised by a medical professional (80 %) or were aware of the potential for permeant hearing loss (78.67 %). We concluded that awareness of the potential for permanent hearing loss with noise and effective methods of hearing protection should be announced to public for preventing NIHL.

• Journal of Preventive Medicine and Public Health
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• v.35 no.3
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• pp.205-213
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• 2002

Objective : Whether exposure to chronic noise induces an increase in blood pressure, or the development of hypertension, has not been established. A cohort study was performed to identify the effects of chronic noise exposure on blood pressure. Methods : 530 males working at a metal manufacturing factory in Busan, Korea were enrolled for the study. They were monitored for 9 consecutive years, from 1991 to 1999, with an annual health check-up. The subjects were divided into 4 groups, which were determines by noise level categories(NLC) according to noise intensity ; NLC-I: office workers, exposed to noise a level below 60dB(A) ; NLC-II: field technical supporters or supervisors, frequently exposed to workplace noise, wearing no hearing protection device; NLC-III: workers, exposed to workplace noise below 85dB(A), wearing ear plugs or muffs; NLC-IV: workers, exposed to workplace noise over 85 dB(A), wearing both ear plugs and muffs. Results : After controlling possible confoundens, such as baseline age, smoking, alcohol intake, exercise, family history of hypertension, systolic(SBP) of diastolic blood pressure(DBP) and changes in BMI (body mass index), the pooled mean for the systolic blood pressures, over the duration of the study period, were 3.8mmHg, 2.0mmHg and 1.7mmHg higher in NLC-IV, NLC-III NLC-II groups, respectively, than in the NLC-I group. There were no significant differences in the diastolic blood pressures between the groups. Conclusion : This study suggests that chronic noise exposure increases systolic blood pressure independently, among male workers.