• Journal of KSNVE
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• v.15 no.2 s.74
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• pp.14-21
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• 2005

• Journal of KSNVE
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• v.16 no.4 s.82
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• pp.23-32
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• 2006

• Journal of KSNVE
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• v.14 no.3
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• pp.31-37
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• 2004

여기에서는 우선 SEA방정식을 소개하고 방정식에 나타나는 SEA파라미터의 물리적 의미와 각 파라미터의 산정과 관련한 이론적 배경을 살펴보고자 한다. (중략)

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.11
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• pp.1097-1102
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• 2010

In this paper, the energy flow analysis(EFA) of the body-in-white door of a real automotive was performed using the energy flow finite element method(EFFEM) to effectively predict the vibrational responses of built-up structures in the medium to high frequency range. To increase the validity of EFA results, the structural hysteresis damping loss factor was measured by the experiment using the concept of statistical energy analysis(SEA). As the excitation frequency increases, the predicted results simulated with EFFEM generally agree with the experimental results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.797-801
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• 2003

The Statistical Energy Analysis is based on the power flow and the energy conservation between sub-systems, which enable the prediction of acoustic and structural vibration behavior in mid-high frequency ranges. This paper discusses the identification of SEA coupling loss factor parameters from experimental measurements of small reverberation chamber sound pressure levels and structural accelerations. As structural subsystems, steel plates with and without damping treatment are considered. Calculated CLFs were verified by both transmission loss values for air-borne CLF case and running SEA commercial software As a result, CLFs have shown a good agreement with those computed by software. Acoustical behavior of air-borne noise and structure-borne noise has been examined. which shows reasonable results, too.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.12
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• pp.999-1006
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• 2014

Mindlin plate theory includes the shear deformation and rotatory inertia effects which cannot be negligible as exciting frequency increases. The statistical methods such as energy flow analysis(EFA) and statistical energy analysis(SEA) are very useful for estimation of structure-borne sound of various built-up structures. For the reliable vibrational analysis of built-up structures at high frequencies, the energy transfer relationship between out-of-plane waves and in-plane waves exist in Mindlin plates coupled at arbitrary angles must be derived. In this paper, the new wave transmission analysis is successfully performed for various energy analyses of Mindlin plates coupled at arbitrary angles.

• The Journal of the Acoustical Society of Korea
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• v.43 no.1
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• pp.112-121
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• 2024

The pipping system is widely used in many industries as equipment for transporting fluids over long distances. In high-pressure pipe, as the speed of the fluid increases, a loud noise is generated. Therefore, various studies have been conducted to reduce pipe noise. In this paper, a pipe noise analysis was developed to predict and quantitatively assess the flow-induced vibration and acoustic-induced vibration due to valve flow in high-temperature and high-pressure. To do this, a high-fidelity fluid analysis technique was developed for predicting internal flow in the pipe with valve. In additional, the contribution of compressible/incompressible pressure by frequency band was evaluated using the wavenumber-frequency analysis. To predict a low/middle frequency pipe noise, the vibroacoustic analysis method was developed based on Finite Element Method (FEM). And the pipe noise prediction method for the middle/high frequency was developed based on Statistical Energy Analysis (SEA).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.90-95
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• 2001

현재까지 고주파수 진동해석에 가장 많이 쓰이는 방법은 통계적 에너지 해석법 (SEA)이다. 그러나 SEA는 많은 가정을 사용하고 있고 시간 및 공간 평균된 에너지 값을 사용하기 때문에 결과에서 알아낼 수 있는 정보가 제한된다. 이러한 단점을 극복하기 위하여 진동 전도 해석법(VCA)이나 파동 인텐시티기법 (WIA)등이 제안되었고, 기하음향학의 한 방법인 레이 추적 기법 (RTM)도 구조음향학에 적용하고 있다. 본 논문에서는 레이 추적 기법을 이용하여 오일러-베르누이 보 이론에 근거한 고정단-자유단 경계조건을 가지는 단일 곡보의 진동 해석을 수행하였다. 예제를 통한 해석 결과, 주파수가 높을수록, 또 감쇠가 클수록 더 정확한 결과를 예측할 수 있음을 관찰할 수 있었으며, 따라서 기존 해석법들의 가정에 적합하지 않은 구조물에 적용할 수 있는 장점이 있다.

• Computational Structural Engineering
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• v.22 no.6
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• pp.49-55
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• 2009

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.711-714
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• 2002

At the lift-off condition, the combustion and Jet noise of launch vehicle produces a severe acoustic environment and the acoustic loads may be damaging to paylaod and equipments. Prediction of the acoustic environment is thus needed to support the load-resistive design and test-qualification of components. Currently, such a high frequency problem is usually dealt with by using the SEA technique, for which the assumptions should match reasonably well with the vibro-acoustic condition of system. The subsystems of SEA model was composed of 16 flat plates, 8 L-shaped beams, and 2 acoustic cavities. The frequency range was 400 Hz - 4 kHz considering the modal parameter. The experiment was performed in a high intensity acoustic chamber, in which the diffuse acoustic field was assured. By comparing the SEA analysis and the experiments, the error less than 5 dB was observed.