• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.483-484
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• 2010

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.460-461
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• 2010

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.415-417
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• 1999

환경연구자들은 대기환경의 개선과 환경기준의 목표달성과 최적 제어기술을 개발하기 위해 각종 모델을 이용하고 있다. 초기 단계에서는 각종 오염인의 배출자료와 기상자료를 이용하여 대기 중 분진의 농도를 추정하는 분산모델 (dispersion model)이 오랜 기간동안 활발하게 이용되어 왔다. 그러나 분산모델은 배출자료의 오차, 수직ㆍ수평적 분산변수의 불확실도, 복잡한 모델 개발에 따른 시간과 비용 등의 문제점을 가지고 있으며, 모델에 포함된 변수에 의해 특성화된 오염원에 대해서만 농도의 추정이 가능하다는 제약점이 있다.(중략)

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.259-262
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• 2006

This paper introduces the process of reducing the automobile wind noise by using acoustic holography. First, a microphone array scans a side or plane under an automible step-by-step. Second, a pressure on a source plane is calculated. Third process is to analyze how much individual sources contribute to interior noise. Fourth process is to control important noise sources determined by the contribution analysis. This paper deals with the entire process, theoretical and experimental problems.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.345-346
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• 2003

서울시 지하철은 1974년 1호선을 시작으로 현재 8호선까지 운행되고 있으며, 40 ％이상의 높은 수송 분담율을 기록하고 있다. 또한 이용 승객의 증가와 함에 주변의 지하상가와 역세권을 형성하여, 주요 교통수단 및 서울시민의 중요한 생활공간으로 자리 잡게 되었다(한근혁, 2002). 그러나 서울시 지하철의 지하역사는 실외공간과 달리 공간적 밀폐성으로 공기질 악화문제에 직면하고 있다(환경부, 2002). (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.10a
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• pp.217-218
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• 2006

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.189-190
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• 2001

서쪽으로 중국대륙과 동쪽으로 한반도로 둘러싸여 있는 황해는 수심이 얕은 대륙붕 구조를 하고 있어 각종 오염에 취약하다. 황해변의 중국 동부쪽 대규모 공업단지들과 한국의 관장, 대불단지, 시화단지 등 대규모 공단에서 배출된 오염물짙이 황해를 오염시키고 있다. 한국과학기술연구원에서는 황해오염을 조사하기 위하여 황해를 대표할 수 있는 도서로 인천에서 남서쪽으로 약 49 km 떨어져 있는 덕적도에 측정소를 구축하여 1999년부터 대기오염물질을 측정하고 있다 (Lee at al., 2001). (중략)

• The Journal of the Acoustical Society of Korea
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• v.24 no.3
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• pp.166-170
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• 2005

This paper describes the experimental study for the position estimation method of underwater sound source using the Nearfield Acoustic Holography. The result confirms that it can be used in the identification of underwater noise sources. The sound sources in the experimental work consists of 2 spherical projectors and the near-Held sound pressure is measured in the hologram plane. From the cross-power spectra of the measured data, the complex sound pressures on the hologram plane is derived and its spatial transformation gives sound fields in a source region. The obtained sound fields in a source region showed that the position of each sound source and their relative source strength are exactly estimated. In conclusion, this technique can be applied for estimation of each source position and its relative strength contribution for the underwater multiple sound sources.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.556-563
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• 2010

The main noise source of the rotary compressor for air conditioner was analyzed by using the measurement of sound intensity, modal analysis and operational deflection shape(ODS) analysis. In this study, the key noise source of rotary compressor was an accumulator, and noise was sharply increased due to the accumulator's resonance which has a big contribution to the noise. To reduce the excessive noise generated from accumulator, structural modification through ODS analysis were applied. Its validation was conducted by the measurement of noise and vibration on the accumulator's surface. The total noise was significantly reduced by 4.2dB(A).

• Journal of environmental and Sanitary engineering
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• v.20 no.3 s.57
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• pp.17-26
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• 2005

Many researches were focused on the data which obtained from chemical bulk analysis. It is difficult to evaluate source contribution by wet type chemical bulk analysis. In this study, we have reviewed the characterization of individual particle for source identification. We analyzed by SEM/EDX methods. We have obtained average geometric particle diameter measured by optical diameter which were resulted from SEM/EDX image scan, representative physical diameter of individual particle was $3.38\;{\mu}m\;in\;A,\;3.67\;{\mu}m\;in\;B$. In the result of image analysis at each spots particles, both samples non-sphere shapes, C-rich particles. In consequence of chemical analysis of individual particle, each sampling sites some elements.