In order to clarify the effect of cooling water temperature on particulate emissions, a single cylinder engine was used for engine test at various cooling water temperature under various engine load.
From the experiment, lower cooling water temperature increased Soluble Organic Fractions (SOF) remarkably, which results in total particulate increment. Dry soot, on the other hand, was little affected by cooling water temperature. Total Hydrocarbon (THC) also increased as the cooling water temperature decreased.
These results indicate that the wall quenching plays an important role on SOF formation as well as THC formation.

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Calcium compound added to gas oil inhibits soot and promotes its combustion. Today it is reported that this catalysis is little effective in low grade fuel. The present paper examined how additive promoted combustion of soot which was produced from fuel oil C. Carbon black and carbon residue were used as models of soot and were mixed with each of two oil-soluble compounds, such as calcium stearate or calcium naphtenate. The mixed samples were heated from 100°C to 800°C with a thermobalance, by changing the content of O₂ and the flow of air which were supplied to them, the rate of heating them, etc. The experiment clarified the two things:
(l) When either carbon black or carbon residue was mixed with over 2wt% of calcium, temperature lowered in this combustion. Then O₂ was over 10vol% and air was over l0ml/min.
(2) Combustion of soot containg calcium affected the shape of soot considerably. Carbon black with large surface area promoted the combustion effectively.

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In recent year, a fin stabilizer has been widely used as a hull stability instrument for a patrol boat, defence ship, car ferry and passenger ship.
This paper presents some investigations on the influence of the fin area and the control method on the reduction of roll with the fin stabilizer in view of full scale test results. In order to select the optimum fin area, it is important to use not only emprical wave slope capacity, but simulation including rolling probability based on hull motion theory as design criteria. The rolling reduction performance by PID control method is decreased under the condition of long periodic wave. This problem however can be solved by newly developed fussy control method.

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Licensers have been recommending the control method that is in proportion to M.E.P. (Mean Effective Pressure) for suitable quantity of feeding cylinder oil on large 2-stroke slow speed marine diesel engine.
But serious abnormal wear troubles on cylinder liner and piston ring, which are caused clearly by physical shortage of cylinder oil, are occurring in succession in spite of feeding the quantity recommended by licensers.
Especially, there are many problems in applying this control method to derating engine.
This situation suggests that the control method in proportion to M.E.P. treat lightly the physical factor (in proprotion to R. P. M.) .
In this paper, authors adovocated Multi, Proprotional Method (Cylinder oil feed quantity is in proportion to B. H. P. and R. P. M. simultarreou sly) for decision of safety and economical quantity fo cylinder oil, and examination the validity of the new method by analysis results of field dada.

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