• Journal of the korean Society of Automotive Engineers
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• v.11 no.1
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• pp.57-67
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• 1989

Acoustic intensity method is applied to a 4-cylinder gasoline engine in order to identify the noise sources and the response characteristics. Acoustic intensity is analyzed by 1/3 octave band filter for each center frequency. Radiational characteristics of acoustic intensity at overall and the maximum intensity level are represented by using the contour and three-dimensional plot. It is verified that this method is effective to the assessment of engine noise. It can be found that the maximum intensity is radiated from the front side of the engine under idling condition and the right side of it under 2, 000 rpm running with no loading condition at overall level, and also that the maximum intensity is radiated from the oil pan and the intake and exhaust manifold at the center frequency of 100 Hz.

• The Journal of the Acoustical Society of Korea
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• v.16 no.5
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• pp.36-42
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• 1997

This paper purposes the measurement method of vibration intensity in building structure which is a method of measuring the intensity and the flow of vibration energy. We derived basic theory and measuring theory for a simple beam, and comparison of the experimental results with calculated results. As a result, according to the calculated value from acceleration distribution and the measurement result from the method of vibration intensity under the condition except near field of measurement zone. The measured results, show that this method is useful for measuring the vibration energy flow in building structure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.355-358
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• 2005

This study aims at comparing the noise characteristics of conventional and functional hood. Measurement and analysis was carried out in anechoic room and actual environment. In case of anechoic room, intensity and sound pressure level were measured. In case of actual environment sound pressure level under different apartment size and distances. Sound pressure level of actual environment was higher than that of anechoic room. It is concluded that noise characteristics were different from each other in case of anechoic room and actual environment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.10a
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• pp.111-115
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• 1995

철도소음의 전파예측을 위한 예측모델의 작성에 매우 중요한 요소가 되는 주행열차로부터의 소음방사특성에 대하여 음향인텐시티법을 이용하여 검토하였다. 그리고 검토결과를 근거로 하여 평탄지 선로를 주행하는 열차를 유한길이의 지향성 점음원열로 가정하고, 지향성계수별(n)로 소음레벨을 구하여 실측치와의 대응성에 대하여 검토하였다. 또한 모터차량이 소음발생에 미치는 영향에 대해서도 검토하였다.