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Interactive, Internet-linked sensor-robotic networks are the next-generation approach to enabling long-term 24/7/365 surveillance of major remote or dangerous processes that are central to the habitability of our planet. The NEPTUNE ocean observatory program will be a leader in this approach. The observatory's 1400-mile network of heavily instrumented fiber-optic/power cable will convert a major sector...
This article presents recent studies made utilising the autonomous underwater vehicle (AUV) r2D4 of the Great Dodo Lava Plain at the Central Indian Mid-Ocean ridge system. r2D4 is a cruising type AUV weighing 1,600 kgf with a length of 4.4 m. It is fitted with a side scanning sonar, an interferometry sonar, a CTDO, and an in-situ chemical analyzer "GAMOS" for measurement of manganese concentration...
On May 29, 2003, the KAIKO's secondary cable snapped, and the KAIKO's vehicle has been missing. JAMSTEC (Japan Agency for Marine-Earth Science and Technology) was decided to remodel the vehicle of UROV7K system instead of the lost vehicle in order to continue the scientific activities. This system is called "KAIKO7000" system. Remodeling of the KAIKO7000 system was finished in March 2004,...
We present results from MBARI's two contrasting missions of MBARI's autonomous underwater mapping vehicle; the first in Monterey Canyon and the second in Barkley Canyon offshore Vancouver Island. The data requirements for both expeditions were similar, to confirm cable routing plans as part of the U.S. Ocean Observatory Initiative (OOI) and Neptune Canada project. The paper compares the data sets...
Manned deep submersible "Shinkai 6500", which has a depth capability of 6500 m, was developed in 1989 by JAMSTEC. She is the deepest manned submersible in the world. Since the operation started in 1990, she contributed to science investigation over 18 years. The Shinkai 6500 achieved 1000th dive in March 2008. She made dives in the trench area around Japan, in the Eastern Pacific Ocean,...
Recently, a number of bacteria have been found from a mud sample of Challenger Deep in the Mariana Trench. Sampling those sediment samples, an ROV to the oceans' deepest depth is needed. But no vehicle gets to the deepest depth in the world. Scientists want to continuously explore the deepest parts of the oceans with a vehicle equipped with sediment samplers. JAMSTEC started developing a sediment...
Underwater sensor networks (UWSNs) promises new opportunities for exploration of the oceans which cover more than 70% of the earth's surface. Researchers envision the deployment of dense networks of untethered sensors underwater for data acquisition to better understand the underwater environment, while military and security forces see the great potential of using this technology for mine reconnaissance,...
A new and effective seafloor geodetic observing robot network system, which consists of several submarine stations situated in regions susceptible to interplate earthquakes, has been proposed and is under construction in Japan. In this system high bit rate and low error rate are required when uploading mass observed geodetic data from AUV to its dock without cable connection. We proposed an acoustic...
Much of the cost and effort of new ocean observatories will be in the infrastructure that directly supports sensors, such as moorings and mobile platforms, which in turn connect to a "backbone" infrastructure, such as cabled seafloor nodes. Three elements of this sensor network infrastructure are in various stages of development: a cable-connected mooring system with a profiler under real-time...
A method of seafloor roughness measurement using low-power lasers and a camcorder mounted on a ROV was demonstrated in the EVA (Experiments for Validation of Acoustics modeling techniques) sea trials, conducted near Marciana Marina, Isola d'Elba, Italy. Six red laser beams were spread by cylindrical lenses into parallel planes. The intersection of the laser planes with the ocean bottom was imaged...
A device for transferring wave-dissipating blocks was developed using net chains to allow for automation and labor saving. The device spreads net chains over a block and then tightens the net chains using a wire rope connected to a crane to lift the block. A model device was used to conduct a transfer experiment under several visibility conditions. A practical device was produced, and transfer work...
In Japan many of port facilities such as breakwaters and quay walls are constructed on the soft sea bottom, and it is necessary to improve these soft grounds before construction of upper structures, in order to maintain the stability of facilities. One of most popular methods of soil improvement in Japan is sand compaction pile (SCP) Method, in which many compacted columns of good quality sand are...
Knowing the temporal change of the seabed, we can understand the nature of the undersea environment in more details. The scale of the features on the seabed varies from meters for large sandwaves, and down to less than one millimeter for the prints left by marine creatures. So far, there is not a single instrument that can cover the whole range and still preserve the resolution. For measuring small-scale...
A parametric study on random internal waves in a two-fluid system is carried out in this paper. Based on the existing study provided by the author, the second-order theory for the interaction of arbitrary two linear waves is adopted to examine its influence on wave profiles. Two modes of wave motion are investigated: the surface (fast) mode and the internal (slow) mode. On the basis of present results,...
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