• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.10a
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• pp.317-322
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• 1994

본 연구에서는 원통면 음향 홀로그래피 방법에 대한 세밀한 고찰을 통하여 이 방법을 이용한 음장예측의 실제 적용에 도움을 주고자 한다. 먼저 원통면 음향 홀로그래피 방법의 기본적인 이론에 대한 고찰을 하였고, 원통면 음향 홀로그래피 방법의 실제 적용시 나타나는 창문함수의 영향(window effect)이나 공간상의 엘리어싱(spatial aliasing), 둘러싸기 오차(wraparound error)와 같은 오차에 대하여 모의 실험을 통하여 살펴보았다. 이러한 오차해석을 통하여 가능한 한 오차를 줄이고 신뢰할 수 있는 예측결과를 얻을 수 있는 측정조건을 제시하였으며, 오차를 감소시킬수 있는 Tukey 창문함수의 사용과 제로패딩(zero padding) 방법을 제시하였다. 이러한 기본적인 이해를 바탕으로 원통형 구조물의 방사음장을 예측하는 실험을 하였다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.10
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• pp.987-995
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• 2009

As an experimental technique to analyze the far-field characteristics of underwater cylindrical array sensors, cylindrical acoustic holography is studied. Inside an laboratory water tank, far-field directivity patterns as well as near-field source images are reconstructed from the measured hologram by hydrophone array. Approximate equation for far-field directivity estimation is derived based on stationary phase method. The simulation and experiment show well usefulness of the proposed method in application of underwater array sensors.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.111-116
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• 2009

As an experimental technique to analyze the far-field characteristics of underwater cylindrical array sensors, cylindrical acoustic holography is studied. Inside an laboratory water tank, far-field directivity patterns as well as near-field source images are reconstructed from the measured hologram by hydrophone array. Approximate equation for far-field directivity estimation is derived based on stationary phase method. The simulation and experiment show well usefulness of the proposed method in application of underwater array sensors.

• Journal of KSNVE
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• v.5 no.1
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• pp.37-48
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• 1995

The prediction of sound pressure using acoustic holography has been recognized as a useful tool for the visualization of sound field. Cylindrical acoustic holography amongst acoustic holographic methods planar, spherical, and cylindrical ones-has a wide range of application since its rather simple construction and easy implementation for the sources. To utilize the propery of cylindrical holographic method, estimation errors associated with holographic parameters such as aperture size and sampling space must be envisaged. In this these errors have been studied by numerical simulation and the relation between the errors and the spectrum in wavenumber domain is described. The results are also confirmed by simple experiments.