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Tsunamis have long been recognized as a significant threat to U.S. coastlines. The National Oceanic and Atmospheric Administration (NOAA) and its predecessor agencies have had operational responsibility for issuing U.S. tsunami warnings since establishment of the Pacific Tsunami Warning Center in 1949. Today's end-to-end U.S. tsunami warning system relies on partnerships with federal, state, territorial,...
According to the Integrated Coastal Ocean Observation System (ICOOS) Act of 2009 the U.S. Integrated Ocean Observing System (IOOS®) Enterprise extends across 17 federal agencies and 11 regional associations and includes numerous actors from within those organizations. One of the primary functions IOOS provides is a Data Management and Communications (DMAC) Subsystem that aims to make discoverable...
A supervised classification routine was used to classify munitions targets and basic seabed types from underwater images. Additional features that were based on the local relief, or height, of the seabed were then added to the classifier and new results computed using the expanded feature set. The height data were generated from the input images themselves using structure-from-motion computer vision...
The JERICO European research infrastructure (RI) is integrating several platform types i.e. fixed buoys, piles, moorings, drifters, Ferryboxes, gliders, HF radars, coastal cable observatories and the associated technologies dedicated to the observation and monitoring of the European coastal seas. The infrastructure is to serve both the implementation of European marine policies and the elucidation...
The need to benefit from economy of scale has driven the design of larger and larger ships with increasing tonnage. The hull structures of large ships are more flexible and the natural frequencies of the hull girder can even fall within the range of wave encounter frequencies resulting in the resonance phenomenon termed springing. A numerical linear hydroelastic investigation of the wave induced motion...
We present a particle velocity sensing scheme for underwater acoustic vector sensors, which utilizes a nature-inspired bionic hair based transduction scheme. The hair based sensor offers an attractive option for particle velocity sensing with low sensor size, but it is limited by low sensitivity. This limitation can be overcome by using an acoustic horn for amplification, and using a sensitive measurement...
We propose a new method to measure the salinity of seawater using a heterodyne double-pass interferometer. Results of preliminary experiments show that the effect of the temperature was reduced by about one order of magnitude when compared with Michelson interferometer. The measured phase difference between pure water and 3.5 ‰ salt water of 182.0 degrees was slightly higher than that of the theoretically...
Recently, Korea Institute of Geoscience and Mineral Resources (KIGAM) is developing an ocean surface/bottom multidisciplinary geophysical observatory that integrates hydroacoustic, seismic, and infrasound technologies. In 2014 Korea Research Institute of Ships and Ocean Engineering (KRISO) developed a prototype of a high-frequency underwater sound measurement module of detecting the hydroacoustic...
This paper researches how to design a constrained model predictive control (MPC) algorithm based dynamic positioning (DP) control system of a supply ship considering system constraints. First, a linear low-frequency motion model with three degrees of freedom necessary for the MPC predictive model is established. Secondly, an MPC algorithm based DP controller is designed considering input constraints...
We present the integration of Blueview's P900 2D forward looking imaging sonars on two vehicles developed at WHOI's Deep Submergence Laboratory and the software to support them. For the Sentry AUV, a 6000m AUV, we developed a software system designed to run on low-power embedded Linux platforms that applies real-time computer vision techniques on acoustic returns intensity images to detect threats...
Modern ocean microbial research utilizes advanced molecular analytical techniques, such as polymerase chain reaction (PCR), DNA and protein probe arrays, and nucleic acid sequencing (etc.). Applying or at least initiating these techniques at the point and time of sample collection can enhance their effectiveness. To that end, in-situ sample processing and real-time molecular detection schemes have...
Measurements of underwater electric potential (UEP) have several possible applications, including geophysical research, gas and oil exploration, and finding underwater cables and unexploded ordnance. In the present investigation, use of an autonomous underwater vehicle (AUV) to perform measurements of underwater electric potential was explored. An AUV was equipped with a spherical electric field sensor...
This paper reports on an algorithm for underwater visual place recognition in the presence of dramatic appearance change. Long-term visual place recognition is challenging underwater due to biofouling, corrosion, and other effects that lead to dramatic visual appearance change, which often causes traditional point-based feature methods to perform poorly. Building upon the authors' earlier work, this...
Using an Autonomous Underwater Vehicle (AUV) for close-proximity operations (e.g., close to the seafloor, a vessel, or divers) requires robust, precise vehicle control. When performing joint human-robot operations, a Robotic Diver Assistant can perform tasks such as tool carrying, worksite illumination, or other tasks that a dive buddy might perform. Precise control of the AUV normally requires accurate...
CariCOOS has implemented a mirror run of the operational numerical weather prediction model employed by the National Weather Service Weather Forecast Office San Juan (NWS WFO SJU), which is based on the WRF NMM model. The model configuration consists of a one-way nesting of two domains with a horizontal resolution of 6-km and 2-km, respectively. CariCOOS developed a single domain configuration of...
The United States Boy Scouts of America (BSA) programs are designed to cover a range of different youth development activities. Central to the BSA program is the merit badge system. Merit badges provide an opportunity for scouts to learn about a specific topic, which may be focused on a hobby, physical activity, or prospective career field. There are more than 120 different merit badges that any Scout...
This paper improves on the accuracy of other published machine learning results for quantifying plankton samples. The contributions of this work are: (1) Clarifying the number of expertly labeled images required for machine learning results. (2) Providing guidance as to what algorithms provide the best performance, and how to tune them. (3) Leveraging an ensemble of models to achieve recall rates...
The development of multiple generations of robotic flapping pectoral fins has warranted a closer study of the relative thrusts and efficiencies exhibited by these fins. This paper describes the differences between the various fins - including stroke frequency, stroke amplitude, aspect ratio, and effective angle of attack - and investigates the effects these differences have on thrust generation and...
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