• International Journal of Highway Engineering
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• v.14 no.2
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• pp.19-28
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• 2012

A measuring technique for tire-pavement interaction noise that uses a proposed noble close proximity(NCPX) method, which has been proofed in terms of the reliability and consistency of interaction noise measurement through several researches, equipped with surface microphones has been adopted in order to perform bridge deck pavement noise evaluations on four different pavement surfaces. Through field testing measurement of bridge deck pavement in Seoul inner ring road, the appropriate noise-measuring procedures have been used for evaluating the noise characteristics of four different surfaces. Measuring results show that tire-pavement noise levels vary depending on the surface types and vehicle speeds. Furthermore, the different characteristics of tire-pavement interaction noise can be found before and after the new surface construction of bridge deck pavements in terms of the 1/3 octave band analysis of vehicle speed.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.396-402
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• 2014

The measurement of air-borne noise in a naval ship is a crucial element. Because the noise in a naval ship interferes with a communication between crews and finally it causes to reduce the combat power. Thus, most of newly built ships have to satisfy the criteria of air-borne noise in the stage of delivery of a naval ship. In order to evaluate success or failure of criteria, uncertainty of the measurement should be considered. This study introduces the test method for the measurement of the air-borne noise in a naval ship and is concerned with the evaluation of uncertainty. The uncertainty results which was from the measurement of air-borne noise in 7 naval ships newly built satisfy the error tolerance(2dB). Therefore, it is need to reduce the error tolerance for the reliable measurement result.

• The Journal of the Acoustical Society of Korea
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• v.29 no.3
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• pp.184-190
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• 2010

Lowering of auditory caused by noise is increased, these days. Especially, people who have noise induced hearing loss by permanent exposure to noise are increased according to spread out of multimedia and improvement of information equipment. The pure tone audiometry used in the hospital presently inspect auditory manually up to 8,000 Hz bandwidth. So the case of noise induced hearing loss which suffered from extended high frequency over 8,000 Hz, there is a problem to prevent hearing loss by precognition. In this paper, we proposed a method to prevent noise induced hearing loss by using extended high frequency bandwidth from 12,000 Hz to 20,000 Hz. We have got a experimental result to fifty of twenties who are often used to earphones through portable equipment. As a result, 36% of twenties show lowering of auditory caused by noise and 2% of them shows severe loss of hearing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.758-761
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• 2005

본 연구에서는 고속도로 발생 소음특성을 측정하여 방음벽 설계 인자를 도출하기 위함이다. 이를 위해 인터체인지 및 영업소 인접부를 포함한 총 20개소를 선정하여 소음측정을 수행하였으며, 소음원의 주파수특성 및 일일 변동특성, 노면 종류에 따른 소음발생특성, 영업소 및 인터체인지 부근에서의 소음특성을 분석하여 방음벽 설계 인자를 도출하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.974-977
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• 2007

본 연구에서는 건설 공사소음 예측 및 가설방음벽 설계를 위해 개발한 공사장 소음예측 프로그램에 대해 소개하고자 한다. 또한, 건설장비가 운영되는 동안 이격거리별 소음측정을 수행한 후 측정결과와 해석결과와의 비교검토를 통해 개발 프로그램의 타당성을 검증하고자 하며, 상용되고 있는 소음해석 전용 소프트웨어를 이용해 다양한 경우에 대한 소음해석을 수행한 후 해석결과를 개발 프로그램의 해석결과와 비교함으로서 개발 프로그램의 타당성을 검증하는 것을 본 연구의 목적으로 한다.

• Environmental and Resource Economics Review
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• v.10 no.4
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• pp.483-494
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• 2001

본 연구는 항공기 소음이 주택가격에 미치는 영향을 헤도닉가격기법을 적용하여 분석하고자 하였다. 국제공항이 인천으로 이전하기 전 서울지방항공청장이 소음피해지역(제1종, 제2종 및 제3종)으로 고시한 김포공항 주변의 아파트 가격을 주요 분석 대상으로 하였다. 소음측정단위로는 세계민간항공기구가 권장하는 연속적 동등소음감지단위(Weight Equivalent Continuous Perceived Noise Level: WECPNL)를 사용하였다. 2000년도 여름에 매매된 총 220가구를 대상으로 아파트의 실질거래가격과 소음측정단위, 가구속성 및 지역관련 변수를 사용하여 헤도닉 방정식을 추정한 결과 소음변수를 비롯 아파트 평수 및 방의 개수를 나타내는 변수에 대한 계수의 추정치는 통계적으로 매우 유의적으로 나타났다. 분석대상지역에 있어 항공기 소음의 한계내포가격은 평균 마이너스 340여 만 원으로 추정되었다. 이 추정치는 다시 말해 소음감지단위인 WECPNL이 한 단위 증가하게 되면 아파트의 평균매매 가격의 3.19%가 떨어지는 것을 의미하며 이 지역이 소음피해지역으로 고시되어 있는 상황을 매우 잘 나타내고 있었다.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.699-706
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• 2016

This study aimed to propose the necessity and system establishment of noise reduction facility via evaluating noise level exposed by the radiographer due to MRI scan. Noise measurements were carried out using at S general hospital in Daejeon using 1.5 Tesla MRI (7 exams) and 3.0 Tesla MRI (16 exams), while using SC-804 noise meter. The measurement distance was from the soundproof door of the MRI room to the radiographer which measured 100cm, and the measurement height, the height to the radiographer's ears when working, 100cm. The noise measured for each exam was an average of three measures per exam which observed the noise occurring in each sequence recorded every 20 seconds. As the results, the maximum of noise exposed by the radiographer is 73.3 dB(A), which is MRCP by the 3.0 Tesla device, and also the maximum of average noise is 66.9(3.1) dB(A), which is Myelogram by the 3.0 Tesla device. Average noise by each device is 61.9(4.1) dB(A) by the 3.0 Tesla device and 52.0(3.1) dB(A) by the 1.5 Tesla device, which comes to the result that the 3.0 Tesla MRI device is about 10 dB(A) degree higher(p <0.001). The noise level exposed by the radiographer does not affect auditory acuity, but the level is able to incur a non auditory effect. The reflect sound can be removed by installing curtains in the rear wall of MRI control room in order to reduce the noises, but, first of all, An institutional system is needed in order to prevent noise.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.378-386
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• 2019

Unlike ship noise that radiates from moving ships, wind noise is caused by breaking waves as a result of the interaction between the wind and the sea surface. In this paper, WNL (Wind Noise Level) was modeled by considering the noise source of the wind as the bubble cloud generated by the breaking waves. In the modeling, SL( Source Level) of the wind noise was calculated using the wind-speed data measured from the weather buoy operated in the coastal area of the East Sea. At the same time as observing the wind speed, NL (Noise Level) was continuously measured using a self-recording hydrophone deployed near the weather buoy. The modeled WNL according to the wind speed and the measured NL removing the shipping noise from the acoustic raw data were compared in the low-frequency band. The overall trends between the modeled WNL and the measured NL were similar to each other. Therefore, it was confirmed that it is possible to model the WNL in the shallow water considering the SL and distribution depth of bubble cloud caused by the wind.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1173-1176
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• 2007

The breaker noise is one of the main noise sources of construction site. It is very important to assess and measure the breaker noise accurately, because the noise labelling will be in effect January 2008 in Korea. Therefore, It is necessary to measure the sound power level of breakers and use a appropriate test method in accordance with international standard. In this study, we measure the sound power level of breakers by using the breaker noise measurement system. This system makes it possible to measure the breaker noise more accurately than to measure the noise of that attached with excavator, because this system can control main factors affecting breaker noise such as hydraulic input power, hydraulic supply pressure, breaker inlet oil flow and so on.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.299-301
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• 2006

본 논문에서는 학교 주변 소음 측정 및 분석을 하였다. 최근 도시인구 집중으로 인한 산업화로 각종 공해문제들을 야기 시켰다. 그 중 특히 환경소음은 교통량의 증가로 인하여 더욱 심해졌다 교육의 질을 악화시키는 학교주변 소음방지 대책의 기본 자료를 제공하고자 측정 및 분석을 하였다. 그 결과 수림과 방음벽의 소음 감소효과가 높은 것으로 나타났다. 향후 학교소음 저감대책을 수립하고 외국과의 상호 비교를 통하여 보다 정확하고 총체적인 원인과 그것에 따른 대책을 세우는 것이 중요하다.