• 산업기술연구
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• 제27권B호
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• pp.59-64
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• 2007

This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2844-2851
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• 2011

The purpose of this study is to set up an acoustic prediction technique and to perform the IL test of scale down noise reducing device for the development of the noise reducing device as the development of 400km/h class high speed train. First of all, the IL prediction of noise reducing device was performed with the 2D BEM method. And the noise test of scale down noise reducing device in anechoic chamber was performed for the verification of acoustic prediction technique and IL performance evaluation. As the results, the acoustic prediction technique for the development of noise reducing device was verified because the averaged IL difference between prediction and test is in 2dB(A). And the measured IL value of noise reducing device is less than 2dB(A), and additional IL with polyester absorption material is increased about 0.5dB(A).

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.675-679
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• 2006

Today, the interior noise perceived by the occupants is an important factor in the design of automotive interior assemblies. Buzz, Squeak and Rattle Noises in a Seats are one of the major concerns mentioned above. In this study, the terms 'Buzz, squeak and rattle' were defined as the noise originating from structural vibrations in an assembly. And, the BSR noise of vehicle seat was investigated and the improvement of BSR noise level was confirmed though the structural treatment based on the structural analysis results from the modal and sound intensity of seat.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.670-677
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• 2009

The purpose of this study is to reveal the quantitative dose-response relationship between the noise emitted in the platform of subway station and the public response. The noise measured in the platform of subway station was used for a jury test. In order to find the factors which influence annoyance response due to the platform noise, jurors were examined for the difference of the annoying response, interrelation of sound quality parameter and annoyance response. The platform noise level was 77.2$\sim$83.9 dBA and the most of passengers at the platform were highly annoyed. And screen door contributes to annoyance reduction of platform noise. The results from analyzing sound quality parameters shows that loudness and annoyance response have a high correlation coefficient.

• 한국소음진동공학회논문집
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• 제12권9호
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• pp.668-673
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• 2002

The sources of wayside noise for the high -speed train are the aerodynamic noise, rolling noise and power unit noise. We should know the major source to control noise radiated from train. In this paper, we present the test results on the wayside noise and the vibration of the rail/sleeper during the passing of Korean Train Express (KTX). It turns out that the major noise sources for KTX are the rolling noise and power unit noise at 300 km/h. Generally, the noise attenuation with distance is independent of train speed. However, the test results show that in the near field the noise levels decrease by about 5~6 ㏈(A) per doubling of distance at speed in the range of 50~120 km/h and about 3~4 ㏈(A)/d.d at 300 km/h.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1193-1196
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• 2003

Noise reduction effect of a pine tree which was used to reinforce a noise barrier was studied by using reduced scale model test. The result show that the pine tree itself was less effective but the combination of pine tree and noise barrier was good for reducing the noise and sight.

• 한국산학기술학회논문지
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• 제16권4호
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• pp.2436-2441
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• 2015

자동차에서 발생하는 BSR 소음은 감성품질로써 최근에 크게 대두되고 있다. 본 논문에서는 차량 시트에서 발생하는 BSR 소음에 대하여 두 가지의 시험법을 적용하였다. 첫째, sine sweep 가진 BSR 시험법을 이용하여 저주파 가진으로 인해 발생하는 고주파의 BSR 소음을 정량적으로 분석할 수 있음을 확인하였다. 둘째, 작동 시 주요 부위 가속도를 계측하는 작동 BSR 시험법을 이용하여 시트의 여러 조절 장치 중 하이트 조절 장치의 작동 BSR 소음원을 분석 할 수 있었다. 이때 내구시험을 통해 소음원을 발생시켰으며 그에 상응하는 BSR 소음이 한 사이클 당 총 14회 발생하고 있음을 확인하였다. 본 논문에서 제시된 두 가지의 시험법은 시트의 BSR 소음을 보다 효과적으로 분석할 수 있다.

• 한국소음진동공학회논문집
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• 제23권9호
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• pp.823-830
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• 2013

The purpose of this study is to develop a noise reduction device installed at the top of noise barrier for further decreasing of noise level of 400 km/h class high-speed railroad. For this, the frequency spectrum of 400 km/h class high-speed railroad was analyzed through the field noise test, and the tuning frequency was determined to design a noise reduction device. The noise reduction device was designed to have noise reduction performance of at least 3 dB(A) using the prediction method(2D BEM) and through the laboratory test with the prototype. Finally, the outdoor test showed that this device could decrease noise level of 400 km/h class high-speed railroad even more than 3 dB(A).

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.907-910
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• 2008

The wheel radiation noise characteristic of Korean tilting train(Hanvit 200) on curved rail under the field test conditions is analyzed in this paper. The test railroad track was selected from Seodaejon to Songjeongri in Honam line. $5^{th}$ and $6^{th}$ car are decided to measure radiation noise level among a train of six cars. The test subject curve radius executed from R400, R500, R600, R700 and R800 segments. The speed of test trains when from R600 and R800 curves existing operation speed and speed up 20% of existing speed. On curved rail at the time of operation speed of Hanvit 200 trains from below 95km/h wheel radiation noise level at $94dBA{\sim}99dBA$, the operation speed from between $100km/h{\sim}144km/h$ wheel radiation noise level at $100dBA{\sim}106dBA$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.447-451
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• 2006

Automobiles become indispensable to our lives of modern days, however, their abrupt increase causes environmental problems. Relevant regulations domestically and internationally, therefore, have been discussed and reinforced for tackling those problems. The current test methods such as ISO 362 which have been adopted in many countries need to be reviewed to be effective, considering the changes in automobile techniques and road conditions. This research is aimed at providing counter-plans for the expected new measures by analyzing both the current and new test methods.