• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.107-109
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• 2006

Since the apartment was built in 1961, the amount of its supply has been increased greatly, especially from the late 70's. The ratio of apartment housing to detached housing was already over 65% in 2000, and now the apartment becomes the most general type in domestic dwellings. But from 90's, the residents of apartment housing have been dissatisfied with the indoor noises and have issued civic petitions. Some national assemblymen front new towns where a high rise apartment is common are interested in This problem, and promise that they try to solve it. The government has also enacted the related regulations. This paper presents the present state and action plans of indoor noise in dwellings. Details on these will be demonstrated at the presentation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.66-70
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• 2005

Noise prediction are required as part of an environmental impact assessment. Prediction method that is used to domestic environmental impact assessment of construction site and industrial site is not applied work operation rate, work position, moving noise source, inner traffic flow, work type and height of noise source etc. The BS5228 methodology is used mainly for assessment of proposed open industrial sites(mineral extraction, landfill etc.), and larger long-term construction sites(typically for major infrastructure projects). also, estimation which consider various effect factor is possible.

• 대한토목학회논문집
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• 제26권1D호
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• pp.1-11
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• 2006

본 연구에서는 소음에 대한 이론적 연구와 도로교통소음에 관하여 살펴보았다. 그리고 국내의 도로소음예측모델을 다른 선진국의 모델과 비교 분석하여 예측인자의 적용현황 및 적용상의 문제점을 도출하였다. 일반식 정립을 위한 사례연구에서는 국립환경연구원에서 제안한 식에 적용한 예측치와 실측치를 비교하여 국내의 도로교통소음 예측모델의 개선점을 살펴보았다. 또한 소음에 대한 통행량과 속도의 관계를 고찰해보기 위해서, 이 식에서 주요 요인으로 사용한 통행량과 속도의 두 요인 중에서 무엇이 더 큰 영향을 가지는지를 회귀분석을 통하여 속도가 통행량보다 더 밀접한 관계가 있음을 알 수 있었다. 따라서 도로소음을 줄이기 위해서는 차량의 통행량의 고려도 중요하지만 차량의 속도 규제가 더욱 중요하다고 볼 수 있다. 지구보정치 도출을 위한 사례연구에서는 도로교통소음이 단지내에 공간적으로 미치는 영향을 분석하고자 하였다. 세 아파트 단지의 도로교통소음을 측정하여 비교 분석함으로써 도로교통소음은 단지내에 평면적 입체적으로 영향을 미치고 있음을 확인하였다. 즉, 소음원에서 거리가 멀어질수록 소음의 크기가 적어지고, 높은 위치로 올라갈수록 소음의 크기는 증가하다가 어느 정도 높이 이상에서는 다시 소음의 크기는 줄어들고, 소음의 방향에 장애물이 있을 경우 소음의 영향이 줄어들었다. 따라서 단지내에 소음이 미치는 영향을 이러한 점들을 고려하여 공간적으로 파악한 단지 설계를 해야 한다.

• 한국소음진동공학회논문집
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• 제12권6호
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• pp.420-430
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• 2002

Rating scales for environmental noise are varied in their calculation procedure. Among them WECPNL (weighted equivalent continuous perceived noise level) is the rating scale for aircraft noise currently being used in domestic and applied only for aircraft noise. However $L_{dn}$ calculated from $L_{eq}$ $L_{eq}$ is used as a rating scale for not only aircraft noise but also environmental noise. Besides, it is easy to calculate and internationally preferred. It is, therefore, not adequate for the evaluation of residents' exposure. Moreover it is very difficult to measure the aircraft noise by WECPNL due to the complicated calculating procedures if automatic measuring system is not used. Accordingly. this study aims to propose alternative evaluation procedure for the aircraft noise. To achieve this purpose, the data measured by automatic measuring system were gathered and calculated with three evaluation procedures : WECPNL $L_{eq}$ and $L_{dn}$, and the results calculated from different methods were compared and analyzed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.754-758
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• 2006

The purpose of this study is to propose calculation and application method of a common factor from different noise source unit such as $L_{eq}$ and WECPNL, A calculation was conducted by method that propose TNO-PG. Also, An applied example is a noise environmental standard of Korea and Japan. After %HA of two country are calculated, noise standards of two countries were compared by using %HA. The result by a equation of %HA is to convert a noise level($L_{dn}$) into a %HA. To calculate a %HA, First $L_{eq}$ is converted into $L_{dn}$. Then, $L_{dn}$, has inputted into and %HA has deduced from a %HA equation of TNO-PG. If the same area is applied the same %HA value according to area categories, it can be applied the same %HA to different noise sources. As a results. a noise levels have computed different values because responses of human change in accordance with a noise sources. This results can be applied to the noise environmental assessment for a domestic railway and aircraft noise.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.125-131
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• 2008

This research tries to analyze and investigate the effects of the noise reduction test for the sound-absorbing materials installed tentatively on Metro Line 5. Though the noise reduction effects of each sound-absorbing material showed that there was about $2{\sim}5\;dB$ compared with before and after of the tentative installation, it shows that the noise reduction effects are reducing because of the section change condition such as dust absorption and the rail abrasion as time passes after the tentative installation. Also, many difficulties are occurring in the maintenance of the orbit facilities because of the installation of sound-absorbing materials. Though various abroad products for noise reduction are imported like this, the researches for the noise reduction effect increase for this and the improvement direction are being required because of the poor circumstance of the efficiency aspect compared to the economic investment effect because those are not suited to the character of domestic Metro.

• 한국환경과학회지
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• 제18권3호
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• pp.263-269
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• 2009

The purpose of this study is to propose an appropriate criterium for proper sound insulation service preventing school classrooms from aircraft noise. The guideline of noise level for school facility by Korean school health law is less than Leq 55 which is less stringent than that of other countries. It has been reported that many students are annoyed and disturbed for their works when they are exposed to the noise level over Leq 55. It is desirable to modify this guideline of indoor noise level for school classroom. The noise level of classroom of which windows are opened was measured relatively high in case the school is located at the outside of the official area damaged by aircraft noise. In order to minimize the influence of aircraft noise on the school classrooms in the vicinity of domestic airport, it is necessary to improve the present criteria of WECPNL 75 for the establishment of the area damaged by aircraft noise from WECPNL 70.

• 한국소음진동공학회논문집
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• 제23권1호
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• pp.3-8
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• 2013

Recently, the impact on hearing induced by using of portable audio equipment have been actively studied. In general, Because they turn the volume up with loud background noise, they may expose to louder noise. In this study, we investigated the maximum noise level of 20 the domestic potable audio equipment and estimated the impact of the hearing induced by portable audio equipment in according to exposure time. As a result, the use of portable audio equipment is assumed to be more three hours when the level of more than 50 % of volume is most likely to affect the hearing.

• 한국자동차공학회논문집
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• 제2권6호
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• pp.29-37
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• 1994

Active noise control of random noise which propatate in the vehicle cabin as a form of spherical wave is the target of this study. In the previous study, the adaptive algorithm for adaptive controller is presented for the application in active noise control system. And for the preliminary study of adaptive active noise control in vehicle cabin as a real system, a computer simulation is performed on the effectiveness of the adaptive algorithm in the amplitude of the pressure fluctuation. This work studies the implementation of multi-channel feedforward adaptive algorithm for the reduction of the noise inside a vehicle cabin using a number of secondary sources derived by adaptive filtering of reference noise source. Multi-channel adaptive feedforward algorithm are verified in numerical simulation and semi-experimental justification of developed system is made on a domestic passenger car. In the results of semi-experimental study, the noise of specific region in the interior of automobile are reduced for the appreciabe sound pressure level in the operating engine rpm and finally this study suggests the capabilities of the real time active noise control in 3 dimensional acoustic fields.

• 한국항공운항학회지
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• 제26권4호
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• pp.155-163
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• 2018

The development in air transport increases noise around the airport. In order to reduce the noise around the airport, International Civil Aviation Organization has made a lot of effort since the 1970s and Many countries, including South Korea, are implementing many noise reduction policies. This paper investigates those noise reduction policies of medium-sized airports with similar frequency to Gimpo, Jeju and Gimhae airports in South Korea and compares eleven airports in Europe, eleven airports in Asia and five airports in America, including Oceania. According to the research, European countries developed and applied the navigation procedure to avoid the noise area according to the characteristics of the airport. In Asia, there are not as many domestic noise reduction policies. In case of the United States, it provides information only on noise-sensitive areas around airports. After having investigated various policies, this research has examined the noise reduction policy of South Korea. It is concluded that new navigation procedures which reduce noise should be developed.