Effect of fumigated fuel on an initial combustion stage of a diesel spray injected into a D. I. diesel engine was studied by measuring an ignition delay period and rate of heat release. Methanol and diesel fuel itself were used as a sub-fuel fumigated into an intake air at an intake manifold. Main results are as follows:
(1) An ignition delay period as a function of an in-cylinder gas temperature is slightly shortened by the methanol fumigation except an ignition prompted by self-ignition of methanol. However, for the diesel fumigation, the ignition delay decreases with an increase of the fumigated quantity.
(2) The ignition delay period affected by fumigated diesel fuel is shorter than that affected by methanol at the same fumigation equivalence ratio and intake temperature.
(3) A rapid combustion occurs with the methanol fumigation, while, the diesel fuel fumigation slightly changes the heat release caused by combustion of a main spray. The maximum rate of the heat release in the initial combustion stage increases rapidly with an increase in methanol fumigation. For the fumigated diesel fuel, the maximum rate of the heat release changes little.

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It is important to develop a method to evaluate both the cylinder oil distribution and its deterioration on the cylinder liner surfaces for two-stroke marine diesel engines. This paper describes a newly developed method for sampling cylinder oil on the liner wall and its evaluation under engine operating conditions.
(1) By periodically opening and closing its lube oil sampling valve via a control device operating in synchronization with the crank angle, the system is capable of automatically sampling the cylinder liner lube oil in a timely manner.
(2) Lube oil pH readings given by the system through its sampling and analysis functions during engine operation, are in fairly good agreement with the pH value which were later determined by analyzing the cylinder liner lube oil deposit sampled with filter paper, after stopping the engine.
(3) The system provides, by sampling from the position of the liner corresponding to the top ring at TDC, the data on lube oil properties, and shows that as the pH value goes down below 4 and retained TBN value drops below zero, the wear of both cylinder liners and piston rings increases appreciably.

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This differential driven shaft generator/motor system has been introduced first in 1987, practical system (200V, 200kW) is introduced to FUKAE-MARUIII in 1988. Since the fundamental structure of the machine is the same as conventional synchronous machine, the output frequency of the machine is corrected to constant by compensating motion of the movable stator.
Test results of starting characteristics of large capacity induction motors (total 30% rated power of the ACG), and voltage regulating characteristics with variable shaft speed or variable load are good agreement to designed procedure.
The machine can be driven as the electronic propulsion motor. Induction starting, synchronization and load characteristics of the machine are also discussed. Since emergency starting of propulsion motor can be established within up to one minute, it presents powerfull function to reliability of the propulsion system.

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Recently modernized vessels have come to establish the energy saving and safe operation of the engine plant by centralization of a lot of information and data gained from various conditions of engine plants using the data logger equipment installed in the wheelhouse and/or the engine control room.
The data logger equipment have been developed into higher grade systems including not only monitoring and alarming functions but also partial operations of marine engine plants. Furthermore, the various stand-by sequence control systems for plant mode change-over based on the micro computer have been utilized for a reduction in number of manual operations to get the stand-by conditions of the plant. These systems however leaves some problems to be improved such as promotion of the flexibility on the utilization, miniaturing the size, etc.
Accordingly this paper deals with the new stan-by sequence control system for marine engine plant mode change-over.
This system is attached to the data logger equipment and has the various functions such as checking of sensors, automatic starting and stopping of auxiliary machinery, and the training ship KAIGI MARU belonging to Marine Technical College has installed the system and its usefulness has definitely been proved.

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For the purpose of realizing high performance, high reliability, and more crew saving of merchant ships, the electronics and electronic techniques have been introduced and applied to marine systems. But, nowadays it seems very difficult to say that such new electronic technologies have been available enough to achieve our objectives, mainly because it is not easy to adapt system design, construction and operation from the viewpoint of the electronics. In particular, some of the difficulties are heavily due to the characteristics of the electronic devices, that is, they are very sensitive to electromagnetic noises with very small power. But, in spite of such situations, there have been not so many materials on how to suppress the noises induced in the electronic systems. Therefore, this report mainly summarizes how to enhance noise immunity and gives very effective and practical techniques for the marine electronic systems.

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