Shipboard electromagnetic interference is a major problem for FRP or wooden hull ship. Electromagetic disturbances to electronic and electric eqipment on board the ship are mainly caused by its own radio transmitters. Some experiment has been made to find out materials which are good for electromagnetic shielding and show high resistance to eddy current on the surface of materials at the ship's rolling movement.
It has been found that knitted wire mesh, punched metals and expanded metals-these matreials show high resistance to the eddy current in themselves-are not effective materials for shielding large space. This paper gives technical information about electromagnetic shielding, such as testing method of material and construction, and general notes for having good electmagnetic shielding for FRP or wooden ship.

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Nowadays planning of most vessels operated by Japanese crews, or Japanese and foreign crews, are intended to apply the automation notation of NK MO-B grade or higher.
At the view to secure safer and more economical navigation with less number of crews, integrated bridge console with total ship's monitoring system in the wheel house is intended to install to save the installation space and to be convenient for short access time to each operation.
Total ship's monitoring system is intended to centralize the each independent computer system for moinoring and control of the plant, by integrating several computer system distributed to hull, navigation, machinery, and cargo parts.
Trends for modern high grade ships monitoring system, hierarchical structure concept, system structure, key technologies, and function of system are described in this paper, focusing on its application on the container vessel.

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As for a indicator, MAIHAK mechanical type indicator is used generally at ship on board. Also, data detected by the indicator are so far mainly Pmax and Pmi on each cylinder. Further detail data analysis was not carried out to data processing was difficult and have a human error. Analysis of combustion data is carried by the portable indicator that is used pressure sensor of a piezoelectricity type. The cylinder pressure data can be recorded at each 1 degree with a crank angle by it. P-θ diagram and P-V diagram, LogP-logV diagram and others can display on CRT display, after it was converted AD. Further-more, the data is turned into a text file and it can display some graphs on the personal computer and record on a floppy disk. Accordingly, it is able to grasp more condition of engine and can assist to failure diagnosis and adjustment by ship member hand. It is investigated and analyzed on the following.
1. Judgement of exhaust valve of opening and closing time and FO in jecton timing by P-V diagram, DP-Dθ diagram
2. Judgement of compression pressure without combustion by P-V diagram, LogP-LogV diagram, a compression diagram.
3. Influence of cylinder pressure data to the deflection of a crank shaft.
4. Judgement of abnormality of FO valve by P-θ diagram.
5. Regression analysis based on a correlation value between Pmax RPM, Pmi, Dp-Dθ, Pcomp and others.
6. Judgement of combustion efficiency by P-θ diagram and heat release diagram.

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A compact shipboard maneuvering support system has been developed that can be operated as a desk-top computer system for installation on bridge. The three main functions provided by the system are : (1) to display a bird's-eye-view on screen indicating the ship's movements, permitting the shiphandler to practice maneuvering by inputting rudder and engine position commands, (2) to verify beforehand his maneuvering plan through a fairway by prescribing transit points and the ship's speed at these points, and (3) retrieving and displaying demanded information from the IMO Maneuvering Booklet. The system thus provides shipboard maneuvering assistance with the ease and familiarity of a video game, while permitting the shiphandler to visually acquire knowledge on the maneuvering characteristics of his ship. The system will also serve ship-designers in studying maneuverability problems and writing the IMO maneuvering booklet.

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