NGK OCEAN LONG-TERM DEEP SEAFLOOR OBSERVATORY

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The "Long-Term Deep Seafloor Observatory" is a large observation system with underwater cables, which allows continuous real-time observation of underwater fluctuating phenomena such as earthquakes, tsunamis over a long period of time.
	(Developed by JAPAN AGENCY for MARINE-EARTH SCIENCE and TECHNOLOGY, NEC and NICHIYU GIKEN KOGYO)

Cable-End Station
	Large observation station at the end of the cable, which is composed of various sensors such as a camera, ADCP, CTD, geo-thermometer.(made by NICHIYU GIKEN KOGYO)
Branch Multiplexer
	Submarine repeater capable of branching optical fibers from the underwater cable.
Joint Multiplexer
	Designed to multiplex and convert electrical signals of multiple sensors such as a seismometer into optical signals. Capable of connecting the sensors on the seabed by ROV.
Battery Pack
	Equipped with a large-capacity built-in lithium battery to supply the power to Joint Multiplexer. It has a self-surfacing feature.
Broadband Seismometer
	High-performance seismometer capable of broadband weak seismic waves. It has a self-surfacing feature.

NICHIYU GIKEN KOGYO is committed to development of observation systems with its accumulated rich techniques.
	・Design of solid frame structures strong enough to endure deployment. ・Layout of the center of gravity/buoyancy to stabilize underwater behaviors at the time of deployment and recovery. (Buoyant material, mounted devices and weight optimumly laid out) ・Exclusively designed built-in acoustic releasers. (Additional self-surfacing feature to facilitate recovery) ・Development and manufacture of lightweight titanium-made chassis and spherical/cylindrical pressure housings resistant to corrosion. ・Design of mechanisms allowing high operability with ROV manipulators.