• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1450-1454
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• 2007

주상복합형 주거공간에 각 실간 Cross Talking에 의한 소음을 저감시키고 실내기의 공기조화로 발생하는 팬의 소음을 저감 시키기 위하여 소음 환기 장치를 개발 하였다. 공명형과 팽창형의 특성을 적용한 복합적 소음기로 저감주파수 대역에 따른 설계가 가능하며 이 소음기 성능시험 결과 특정 주파수 대역에서 20dB이상의 삽입손실치가 발생하고, 삽입에 의한 압력손실 2mmAq 이하가 됨을 확인하였다. 본 개발품의 특성은 구조가 간단하고 분해조립이 가능하여 설치 및 유지보수가 용이한 제품이다.

• The Journal of the Acoustical Society of Korea
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• v.33 no.6
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• pp.351-357
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• 2014

In this paper, flow noise characteristics of the hybrid vertical-axis wind turbine is investigated. Hybrid vertical-axis wind turbines consisting of two types of vertical-axis wind turbines, Savonius and Darrieus, are devised to maximize merits of one turbine and thus minimize demerits of the other turbine. In order to predict flow noise radiating from hybrid vertical-axis wind turbines, hybrid computatioinal aero acoustic techniques are used. First, unsteady flow fields around the turbine are predicted using computational fluid dynamics method. Then, the flow noise radiations from the turbines are predicted by applying acoustic analogy to the predicted flow fields. Based on numerical results, noise characteristics of a hybrid vertical-axis wind turbine is investigated and is compared with those of Savonius and Darrieus wind turbines.

• The Journal of the Acoustical Society of Korea
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• v.33 no.1
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• pp.40-47
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• 2014

Interaction between the unsteady flow emitted from the blade of the centrifugal fan and the volute tongue region of fan duct is known as the main noise source of the centrifugal fan. In this paper, the relative contributions of the volute tongue region of the centrifugal fan is analyzed to utilize as the foundation data of low noise design. The internal hybrid CAA (Computational Aero-Acoustics) method is used to predict noise radiated from the main noise source. This method is the noise prediction technique using CFD (Computational Fluid Dynamics), Acoustic analogy, and BEM(Boundary Element Method). The relative contributions of the centrifugal fan volute tongue region using the hybrid CAA method show that the region between the cut-off and the scroll has high contribution than the region between the cut-off and the outlet and the hub region of blade has high contribution than the shroud region of blade. These results is utilized as the important data for the development of low noise centrifugal fan.

• The Journal of the Acoustical Society of Korea
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• v.31 no.6
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• pp.391-398
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• 2012

In this paper, prediction of centrifugal fan was conducted through combination the hybrid CAA method which was used to predict the fan noise with the FRPM technique which was used to generate the broadband noise source. Firstly, flow field surround the centrifugal fan was computed using the RANS equations and noise source region was deducted from the computed flow field. Then the FRPM technique was applied to the source region for generation of turbulence which satisfies the stochastic features. The noise source of the centrifugal fan was modeled by applying the acoustic analogy to the synthesized flow field from the computed and generated flow fields. Finally, the broadband noise of the centrifugal fan was predicted through combination the modeled noise source with the linear propagation which was realized using the boundary element method. It was confirmed that the proposed technique is efficient to predict the tonal and broadband noises of centrifugal fan through comparison with the measured data.

• Journal of the KSME
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• v.29 no.5
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• pp.464-468
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• 1989

환경측면에서의 소음. 진동은 교통기관(도로, 철도, 항공기 등), 공장, 건설공사 및 생활 등에 기 인하여 발생되는 것으로, 어떤 지역에서의 소음. 진동은 이들이 개별적 또는 복합적으로 합성된 양상을 띠고 있다 하겠다. 본고에서는 환경측면에서의 소음. 진동 저감을 위한 제도적 방안으로, 현행 환경보전법에 정한 기준과 더불어 공장의 소음. 진동 대책을 소개하고자 한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.131-132
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• 2008

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.202-203
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• 2012

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.4
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• pp.255-265
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• 2015

Shelter system is applying to weapon systems as usage of performing specific mission with arranging several electronic equipments and operators. Recently the electronic equipments is changing from development products to COTS(commecial off-the-shelf) for demonstrating high performance at low cost. As internal operators of shelter system conduct several missions for specific or long time in this present situation, one of the most important element considering the best combat power is internal noise level. Therefore, I desire to analyze the features and foresee multiple noise level with test for conforming whether requirements of design is met or not in this research paper.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.60-65
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• 2014

Shelter system is applying to weapon systems as usage of performing specific mission with arranging several electronic equipments and operators. Recently the electronic equipments is changing from development products to COTS(Commecial on-the-shelf) for demonstrating high performance at low cost. As internal operators of shelter system conduct several missions for specific or long time in this the present situation, One of the most important element considering the best combat power is internal noise level. Therefore, I desire to analyze the features and foresee muliple noise level with test for conforming whether requirements of design is met or not in this research paper.

• Journal of KSNVE
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• v.25 no.6
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• pp.11-15
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• 2015