Results 51 to 60 of about 228,033 (349)

Matched cross‐spectrum phase processing for source depth estimation in deep water

IET Radar, Sonar & Navigation
Zhou et al. (2022) proposed a method for instantaneous source depth estimation in deep water using matched beam intensity processing (MBIP) that leverages depth‐related oscillatory features arising from Lloyd's mirror interference in the frequency domain
Lisheng Zhou, Xiaohong Yang, Guangying Zheng, Fangwei Zhu, Fangyong Wang   +4 more
doaj   +1 more source

Simulated Research on Passive Sonar Range Using Different Hydrographic Conditions

MATEC Web of Conferences, 2015
As an example using the passive sonar, it calculated the quality factor of passive sonar using the sonar equation. The sound field was calculated under different depth and range using multiform hydrographic conditions.
Han Jing, Zhang XueGang, Meng ChunXia, Cao Feng   +3 more
doaj   +1 more source

Study on the Classification Performance of Underwater Sonar Image Classification Based on Convolutional Neural Networks for Detecting a Submerged Human Body

Sensors, 2019
Auto-detecting a submerged human body underwater is very challenging with the absolute necessity to a diver or a submersible. For the vision sensor, the water turbidity and limited light condition make it difficult to take clear images.
Huu-Thu Nguyen, Eon-Ho Lee, Sejin Lee
doaj   +1 more source

Underwater Excavation Records Using Underwater Acoustic Survey: A Case Study in South Korea

Applied Sciences, 2021
The most effective method for surveying underwater archeological sites is visually identifying areas with relics or remains through diving surveys. However, during underwater excavations, it is difficult to obtain images in turbid water.
Young-Hyun Lee, Jin-Hoo Kim, Sang-Hee Lee, Sung-Bo Kim   +3 more
doaj   +1 more source

Balancing SoNaR: IPR versus Processing Issues in a 500-Million-Word Written Dutch Reference Corpus [PDF]

, 2010
In The Low Countries, a major reference corpus for written Dutch is beingbuilt. We discuss the interplay between data acquisition and data processingduring the creation of the SoNaR Corpus. Based on developments in traditionalcorpus compiling and new web
De Clercq, Orph´ee, Heuvel, Henk van den, Jong, Franciska de, Oostdijk, Nelleke, Reynaert, Martin   +4 more
core   +4 more sources

Underwater Side-Scan Sonar Target Detection: YOLOv7 Model Combined with Attention Mechanism and Scaling Factor

Remote Sensing
Side-scan sonar plays a crucial role in underwater exploration, and the autonomous detection of side-scan sonar images is vital for detecting unknown underwater environments. However, due to the complexity of the underwater environment, the presence of a
Xin Wen, Jian Wang, Chensheng Cheng, Feihu Zhang, Guang Pan   +4 more
semanticscholar   +1 more source

Deep Learning Methods for Assessing Time‐Variant Nonlinear Signatures in Clutter Echoes

Advanced Intelligent Systems, EarlyView.
Motion classification from biosonar echoes in clutter presents a fundamental challenge: extracting structured information from stochastic interference. Deep learning successfully discriminates object speed and direction from bat‐inspired signals, achieving 97% accuracy with frequency‐modulated calls but only 48% with constant‐frequency tones. This work
Ibrahim Eshera, Gaurav Duggal, Rolf Müller   +2 more
wiley   +1 more source

Inference of Bubble Size Distribution in Sediments Based on Sounding by Chirp Signals

Archives of Acoustics
A method is proposed to estimate the bubble void fraction and bubble size distribution in marine sediments based on measured sound speed and attenuation data in gas-bearing sediments.
Xiaohong YANG, Guangying ZHENG, Fangyong WANG, Fangwei ZHU, Linlang BAI   +4 more
doaj   +1 more source

Sensor Modeling for Underwater Localization Using a Particle Filter

Sensors, 2021
This paper presents a framework for processing, modeling, and fusing underwater sensor signals to provide a reliable perception for underwater localization in structured environments.
Humberto Martínez-Barberá, Pablo Bernal-Polo, David Herrero-Pérez   +2 more
doaj   +1 more source

Use of high resolution sonar for near-turbine fish observations (DIDSON) - We@Sea 2007-002 [PDF]

, 2010
In this study we investigate small scale distribution of pelagic fish within a windfarm by means of a high resolution sonar (DIDSON, Dual frequency IDentification SONar; Soundmetrics).
Burggraaf, D., Couperus, A.S., Keeken, O.A., van, Kooten, T., van, Tribuhl, S.V., Winter, H.V.   +5 more
core   +1 more source