(3) Finished work quality control system
The ship is equipped with total 10 auto-read depth meters in the longitudinal direction and in the right-to-left direction of the Tremie pipes, and total 2 draft meters at the stem and the stern. The ground height is obtained by the mean draft of the ship hull, the tide level and the auto-read measurement values, and the finished work quality is constantly displayed on the “execution control monitor” together with the ground shape before and after the sand spraying. The tide level is automatically inputted from the RTK-GPS (Z value), or the values from the tidal station, etc., is manually inputted.
(4) Earth and sand discharge system
Eight pairs of the discharge gates and oscillation feeders are provided on a lower part of the hopper, and the oscillation feeders can control the quantity of sand to be discharged by changing the frequency. The opening of the discharge gates, the frequency of the oscillation feeders, and the ship speed can be remotely set from the operator's seat. Every oscillation feeder is equipped with the sand quantity detector, detects and records the quantity of the discharged sand, and outputs the detected and recorded values as the execution records.
Reference
1) WORK VESSEL No. 236 March 1998
2) WORK VESSEL No. 240 November 1998
3) WORK VESSEL No. 241 January 1999
[Isao YOSHIDA]
12. Electronics Technology
12.1 EMC (Electromagnetic Compatibility Directive) (89/336/EEC91/236/EEC92/31/EEC93/68/EEC)
In the midst of the promotion to unify the common market by the European Union, the European Committee has proceeded the establishment of the unified standards for the purpose of removing technical obstacles on the safety of industrial products. The technical obstacles include the safety standards on the commodities, the shop standards, and the policy on the consumer protection from defective commodities, and the directives (EC Directives) on the product safety have been issued one after another so as to remove such obstacles, and free distribution of the products is achieved in the EU area, and at the same time, the common safety of the products themselves is requested.
In the M.E.S.J., the surveys on the CE marking were carried out, and the “Report on the Survey of CE Marking” was prepared in December, 1998.
Among the EU directives, the EMC directive on the electromagnetic compatibility is required to completely come into force on and after January 1, 1996, and applicable to electronic and electric equipment intended for Europe, but there is difference in interpretation concerning the marine structure intended for Europe depending on whether the structure on which the equipment is mounted is of fixed type or of mobile type, and it is necessary to obtain the confirmation from each government.
The standards on EMC has been stringent mainly in developed countries, and it can be emphasized that the environmental consideration on the electronics technology is further requested in future.
Furuno Electric Co., Ltd. established a new company to give the inspection service on the electromagnetic compatibility that the electronic equipment outputs any unnecessary electromagnetic waves, and that the equipment is malfunctioned when subjected to the electromagnetic waves, and the new company started its service since March, 1998.
12.2 INTRANET
The system in which various kinds of on-board information is comprehensively controlled by the on-board network, and transmitted to the shore side through the satellite communication aiming at the safety and efficiency of the ship operation, has been put into practical use.
Uzushio Electric Co., Ltd. announced the ship-shore INTRANET at “SEA EXHIBITION 98” held in Yokohama in March, 1998. The system can achieve the communication of the voice, the image and the data between the ships and the shore stations through the satellite link. Concerning the outline of the system, the Internet is used, the server is installed on board the ship, each equipment is connected through the Internet to construct the in-board INTRANET, and the information communication between the shore (the shipping company) and the INTRANET is achieved through the International Maritime Satellite Organization (INMARSAT). The system was completed by developing the gate-way function capable of bridging the MiTS network and the data to UMS-50.
12.3 Other Systems
Nishishiba Electric Co., Ltd. developed the stabilization control added automatic voltage regulator, and the system was mounted on the Ferry engaged in the Japan Sea route.
