Sumitomo Electric Industries, Limited

Japan National Oil Corporation

Japan Marine Science and Technology Center

Masayoshi Yamaguchi

Ryosuke Hata

Toshio Hagihara

Masayuki Hirose

Yuji Nakura

Taro Aoki

Hiroyuki Kimura

Fumihiko Yonemori

Mutsuo Hattori

Toshiyuki Amagai, Deceased

Tetsuji Ito

The underground-laying depth of an electric power cable is obtained on the basis of temperature data of the electric power cable laid underground, ambient temperature data of a place where the electric power cable is laid underground, calorific power data of the electric power cable, thermal resistivity of soil where the electric power cable is laid underground, and radiation thermal resistivity of the surface of the electric power cable. The ambient temperature means the temperature of a place which is not influenced by the heat of the electric power cable.

Electrical power cable underground laying depth measuring method

An optical-fiber incorporated longer-sized subaqueous unit comprises optical fiber units arranged inside or outside a plastic sheath provided on the periphery of the core body of the longer-sized subaqueous unit such as power cable core or water supply tube. Each optical fiber unit includes an optical fiber accommodated in a metal pipe having on its periphery a coating layer made of plastic material with a melting point higher than that of the material of the plastic sheath, and armoring iron wire bundles are further provided outside the plastic sheath on the periphery of the core body, thereby preventing any buckling in the optical fiber units.

Optical-fiber cable incorporated longer-sized subaqueous unit

A method of monitoring cell culture which comprises digitizing an image of cultured cells inputted to an image processing equipment through a TV camera connected with an observing means and measuring the number and cell proliferation of cultured cells by a processing with using a spatial filter, can treat a large amount of cells in a short time and give a precise number of the cells.

Method of monitoring cell culture

A measuring system measures temperature distribution in water using an optical fiber. An optical fiber cable suspended from a ship and towed by the ship to form an arch within the water. A measuring device for continuously measuring temperature at various points along the lengths of said optical fiber cable. Sensors are provided within the water to calculate the water depth at each of the various points along the length of the arch shaped optical fiber. Thus, a temperature distribution at each water depth can be continuously measured.

Water temperature distribution measurement system employing optical

An optical fiber cable for towing. An elongated central conductor includes a plurality of spiral grooves in the outer periphery thereof. Optical fibers are mounted within each of these grooves by use of a waterproof compound. An insulating layer covers the central conductor and the optical fibers. An outer conductor formed by a plurality of strands of conducting wire are wound about this insulating layer. A composite tape formed of a copper tape and an insulating tape is then wound about the outer conductor. The copper tape portion of the composite tape is in contact with the wire which forms the outer conductor. An armor layer of wire is wound about this entire structure. This arrangement provides an optical fiber cable with improved strength, ease of manufacture, and improved electromagnetic shielding.

Towing composite coaxial optical cable

An optical connector assembly has a female connector having a recess formed in its front surface, and a male connector having a cavity and having a projection formed on its front surface which is partly or entirely deformable so that the tip of an optical fiber supported by the projection will ensuredly be fitted into the innermost portion of the recess. Incoming/outgoing beam surfaces at the innermost part of the recess and at the tip of the projection are defined by the end faces of optical fibers extending through the female and male connectors. A collimater lens may be provided on the end face of each optical fiber for enlarging the diameter of transmitted beams and for deflecting the beams in parallel, so that transmission loss caused by dust in the water is kept to a minimum level. A device for forming jet streams is provided at the joint surfaces of the male and female connectors which serves to jet water or a detergent stored in a storage chamber to the end faces of both optical fibers and to blow away dust, when the connectors are connected, thereby reducing the transmission loss caused by the dust.

Growing community of inventors

Osaka, Japan

Masayoshi Yamaguchi