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Development of broadband high frequency sub-bottom profiler
Proceedings of the Thirteenth ACM International Conference on Underwater Networks & Systems, 2018A high frequency 1 sub-bottom profiler with a central frequency of 110KHz and a bandwidth of 30KHz was developed. The instrument has a better resolution than 5cm for the shallow layer of the seafloor and is used to detect acoustic characteristics of seafloor sediments. The instrument can eventually operate at 6000m depth. The test results show that the
Xinghui Cao +4 more
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Automatic Detection of Pipelines From Sub-bottom Profiler Sonar Images
IEEE Journal of Oceanic Engineering, 2022Sub-bottom profiler (SBP) measurements play a very important role in marine pipeline detection and checking. However, sometimes because of bad sea conditions and complex underwater environments, only poor SBP images can be obtained. Pipeline recognition based on a poor SBP image manually is tedious and has low accuracy.
Shaobo Li +3 more
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Sub-bottom profiling using ocean ambient noise
The Journal of the Acoustical Society of America, 2004Spectral factorization is shown to restore the phase of an incoherent layered sediment reflection coefficient so that its Fourier transform is the minimum phase impulse response at each angle. The method requires the reflection coefficient to be known over a range of frequencies and the grazing angles in question to be above critical.
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Sub-bottom profiling by inverting ambient noise
The Journal of the Acoustical Society of America, 2003In this paper a technique based on spectral factorization for restoring the phase of incoherent bottom sediment reflection coefficient measurements is presented, so that by Fourier transformation one can then obtain the minimum phase impulse response at each grazing angle.
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Research on high frequency sub-bottom profiler experimental results
Proceedings of the Thirteenth ACM International Conference on Underwater Networks & Systems, 2018In the first half of 2018, the high-frequency sub-bottom profiler completed a series of engineering prototype test and verification. Among them, in the April 6, 2018 to April 12, the device for the first time in Hangzhou thousand island lake area lake water work, on May 24, 2018-2018 on May 31, the device has been conducted on the golden pond in Ningbo
Xinghui Cao +3 more
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Identification of the bedrock level with sub-bottom profiling data
Proceedings of the 7th International Symposium on Earth Resources Management & Environment, 2023This study dominantly inquiries about the accuracy of the interpretation of sub-bottom profiling data for the identification of the bedrock level that is essential for underwater constructions and other marine activities. Although the physical core samples give the data more accurately, it is expensive and time-consuming.
K.R.H.I. Rathnayaka +5 more
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Shallow water multichannel sub-bottom profiling using Kirchhoff imaging
The Journal of the Acoustical Society of America, 2018Single-channel sub-bottom profilers are commonly used for shallow water seismic investigation. This work reports the design and construction of a multiple channel profiler that allows more effective seismic imaging techniques. The system is composed of a controlled acoustic source and a 1.6 m long array with eight evenly spaced receiver channels, and ...
João P. Ristow +4 more
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Neural network for geoacoustic inversion of sub-bottom profiler data
Proceedings of Meetings on AcousticsSub-bottom profilers are utilized to extract features pertaining to the sub-seafloor environment sediment stratification. Acquisition and analysis of sub-bottom profiles can provide insight into the sediment composition and acoustical properties. Typical analysis of profiles involves computationally expensive inversions, such as model-based or Bayesian
Justin Diamond +2 more
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A high-power, low-frequency sonar for sub-bottom profiling
Radio and Electronic Engineer, 1963This is a continuous sub-bottom profiling system designed to give high resolution whilst retaining good penetration. By mounting the output transducer in the bottom of a fibreglass dinghy, towed well astern of the survey ship, the shortest possible output pulse has been achieved, and by using a line hydrophone towed between the ship and dinghy a very ...
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