The Journal of the Acoustical Society of Korea

한국음향학회 (The Acoustical Society of Korea)
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Wave Reflection from Porous Ocean Sediment With Depth Dependent Properties

  • Lee, Keun-Hwa (Dept. of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Seong, Woo-Jae (Dept. of Naval Architecture and Ocean Engineering, Seoul National University)
  • 발행 : 2006.03.31
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초록

This study examines the reflection characteristic of a thin transition layer of the ocean bottom showing variability with respect to depth. In order to model the surficial sediment simply, we reduce the Biot model to the depth dependent wave equation for the pseudo fluid using the fluid approximation (weak frame approximation). From the reduced equation, the difference between the inherent frequency dependency of the reflection and the frequency dependency resulting from a thin transition layer is investigated. Using Tang's depth porosity profile model of the surficial sediment [D. Tang et al., IEEE J. Oceanic Eng., vol.27(3), 546-560(2002)], we numerically simulated the reflection loss and investigated the contribution from both frequency dependencies. In addition, the effects of different sediment type and varying depth structure of the sediment are discussed.

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참고문헌

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