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Ocean Environmental data is a key component utilized by the United States Coast Guard (USCG) when developing and executing a search and rescue mission. The Search and Rescue Optimal Planning System (SAROPS) became operational with the USCG in 2007 and is the main tool for developing search and rescue mission plans. This tool utilizes environmental data (wind, ocean currents, etc.) to estimate the...
Underwater vehicles are usually designed with additional degrees of freedom than those required to accomplish given manipulator tasks. A robot platform should be effective to maintain its position and orientation in order to attain diverse underwater tasks. This study addresses the dynamic modeling of an autonomous underwater vehicle (AUV) which consists of tilting thrusters for hovering motion to...
The purpose of this research is to develop a solar-powered autonomous surface vehicle (SASV) for the use of ocean environment monitoring and underwater passive acoustic monitoring of marine mammals. Measuring items of the logger version CTD with optical fast DO sensor are depth, temperature, conductivity, salinity, dissolved oxygen, chlorophyll and turbidity. The authors have also developed kinds...
We have developed an automated cable-laying system that is operated with a remotely operated vehicle (ROV) and can automatically dispense a thin optical-fiber submarine cable at a rate that keeps pace with the ROV's ground speed. The use of an ROV allows to install a thin optical-fiber submarine cable on the deep seafloor accurately and safely. The ROV-based automated cable-laying system is being...
Thermocline has a significant impact on marine fishery, navy submarine activity, ocean circulation and internal wave. In consideration of long range, low cost, and high maneuverability, the AUV (Autonomous Underwater Vehicle) is an ideal platform for ocean local precisely thermocline tracking. Combining with the advantage of the AUV yo-yo movement, this paper presents a simple and effective thermocline...
In underwater wireless optical communications (UWOC), impulse response is important to characterize channel properties. In this paper, we consider the impulse response for UWOC multiple-input single-output (MISO) links with a uniform circular array (UCA) of light sources. The Monte Carlo approach is adopted to achieve the impulse response of UWOC MISO links for the turbid water environment. We propose...
Most studies on zooplankton image processing are focused on global texture feature. In this paper, an efficient method for classifying zooplankton images by combination of local binary pattern (LBP) is demonstrated. The classification performance of plankton image with global and local features have been evaluated and the overall performance of combination of these features for zooplankton identification...
In this paper, we present some of the results of the Tallinn trials. The trials were part of the ARROWS (ARchaeological RObot systems for the World's Seas) FP7 project whose aims are to reduce the cost of the AUVs and sensors in order to generalize their use for underwater archaeological missions. To this end, we developed algorithms to improve the imagery resolution of wideband sonar systems with...
In this paper, we discuss the PAS (Pulse Active Sonar) and CAS (Continuous Active Sonar) strategies for target detection and tracking. CAS system potentially offer several advantages over traditional PAS systems, mainly in term of probability of detection and/or tracking. With a continuous insonification of the target, CAS can track continuously limiting the data association error inherent to PAS...
The numerical study on the effect of flapping foils with a modified shape on efficiently bio-mimetic propulsion is presented. A symmetric 4-digit NACA0006 foil was used as a baseline in this work, the design of modified foils were derived by altering NACA0006 foil leading section as thicker NACA foil's counterparts and keeping its trailing section unchanged, and as a result, the modified foils were...
Quay mooring status of a ship has been studied by using the mooring analysis software AQWA. The anti-typhoon mooring computation under the combined wind wave and current loads was analyzed with a time domain computation method. The influence of the mooring line material and mooring layout has also been studied on mooring system tensions. According to the research, the mooring layout plan that complies...
The acoustic properties including sound speed and the attenuation coefficient are important factors which determine the efficacy of acoustic equipments and targets detection of seafloor sediments. This paper presents a multi-mode acoustic in situ measurement system to be used in the deep sea. We analyzed the major system framework and relevant hardware and software. The proposed system provides two...
In this paper, the wideband Capon cepstrum weighted l2, 1 minimization algorithm (WB-CW l2, 1) is presented for wideband direction of arrival (DOA) estimation using an acoustic array. The problem of wideband DOA estimation is converted into the estimation of the sparsity pattern of a jointly sparse signal and then solved by the weighted l2, 1 norm minimization. WB-CW l2, 1 uses the Capon cepstrum...
Operational ocean observing system (OOOS) can meet the needs of marine disaster prevention and reduction, safeguard socio-economic development in coastal zones, and promote marine resource exploitation. As a solid foundation for the establishment of the OOOS, operational ocean observing equipment (OOOE) is attached great significance across the world. Three kinds of OOOEs in China are introduced and...
Intensive cultures of shrimps produce more than 10 individuals per square meters with the use of hatchery reared post-larvae and the supply of compounded diets. The paddle wheel aerators are usually installed in the pond to supply oxygen and collect the sludge generated from the excretion of shrimps and the rest of the compounded food. The operation of paddlewheel aerators consume plenty of oil or...
Temperature has a notable effect on sound speed and attenuation of sediment both in theoretical analysis and in laboratorial measurement. The speed of sediment is positively correlated with temperature universally, but the relationship between attenuation and temperature may be more complicated. In the paper, based on the analysis of influence of permeability, frequency, and other physical parameters...
In this paper, we propose a novel approach for SSS registration based on modified phase correlation, which is capable of handling low resolution and noise. The modified phase correlation combines threshold segmentation with phase correlation to carry out side-scan sonar (SSS) image registration. Image registration aims to transform images obtained from different views to the same coordinate. Underwater...
The aim of this work is the characterization of seafloor using bathymetric images segmentation. The bathy-metric image is considered as set of oriented wave profiles generated, in general, by unidirectional currents (water flows constantly in one direction) where each profile can be viewed as the superposition of fast oscillations (ripples) and slow oscillations (sand waves). Due to the texture and...
The realization and key technology of a medium-load underwater electric manipulator is researched for the demand of the small and medium deep-sea underwater vehicle. The manipulator consists of electric linear cylinder module and wrist-clamp module. The linear cylinder can offer large linear force and displacement feedback to realize positioning control, and the wrist-clamp module can output continuous...
This paper presents one syntactic foam with excellent mechanical properties and prominent hydrostatic pressure performance for 11000 meters deep-sea. The properties of the syntactic foam are studied on the basis of relevant standards. The compressive strength, compressive modulus and shear strength of syntactic foams are about 100MPa, 1300MPa and 40MPa separately in atmosphere environment. The water...
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