There are various experimental methods for the measurement of stress intensity factors. However, generally speaking, most of these methods are rather tedious.
The method of Caustic has proven to be a powerfull optical technique to measure stress intensity factors in static and dynamic fracture mechanics. This method was introduced first by Manogg in 1964 who analyzed for a stationary crack under mode-I-loading. After that, this method was further developed and extended by Theocaris and Kalthoff who applied to elastodynamic crack problems, inelastic crack problems and so on. This technique has high accuracy of the measurement, still it is easy to make a experiment. Besides the usual equipment for photography, only a point light source is required.
The method of Caustic utilizes the information from the stress-strain-field within a small region very close to the crack tip. So, any knowledge about external loading and geometric boundary conditions is not necessary.
In this paper, the outline of this method, especially in measuring the static stress intensity factors under mode -I-loading is shown and the applicability of this method is clarified.
On the experiment, optical transmission arrangement with the 5mW He-Ne laser and optical isotropic specimen made of acrylic resin is used. Moreover, several problems concerning this method are investigated.

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An experimental study on combustion characteristics of a single oil droplet hanged on a quartz filament was performed to investigate the effect of fuel oil composition on combustion. Fuel oils used in the experiment were twenty-seven residual oils which had been supplied at the port all over the world for marine use and two residual oils which had been directly supplied from the Japanese oil refineries.
The result shows that the combustion characteristics of single droplet oils under the atmospheric condition have good relationship with the molecular weight distribution of oils. Splashing of a oil droplet during burning was observed in the last stage and also in the early stage of burning period. The mechanism of the splashing in each stage is discussed.

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This paper presents the investigation into the actual performance of marine diesel generator engines, The following conclusions are obtained;
1. The allowable maximum load of the engines has been limited between 60 and 70% of the rated output in less than several years after launching.
2. The maximum load is limited by an upper bound of an exhaust gas temperature at a cylinder exit, which is set up at 400°C in the investigation.
3. The reduction of the maximum load is caused by a secular change of an engine, which produce gradual increase of the exhaust gas tempreature.
These results suggest the necessity of counter-measures to a new-built ship to decrease exhaust gas temperatures and to employ higher power ratio of a diesel engine to a generator.

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The highly modernized and rationalized ships have been increased in the construction number. In order to get the effective and efficient way of the operation, the minimum manning levels which are sustained by suitably specialized seaman team are to be applied.
In this case, each seaman has at least to have the required minimum technique about the operation of the propulsion system such as the operational procedures of main engine through any conditions, i.e., from dead ship to run up mode, and monitoring methods including detection of malfunction and fault of working machineries. For the training of these kinds of technique, the simulator based on a modernized ship has been developed and has been presented to the marine engineers and navigators at the Marine Technical College. This kind of simulator seems to the first that has so far introduced into the Japanese seamen training field.
This paper deals with the conception and the application of the simulator which can usher in a new era of training for sea-going personnel.

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We should like to report on the methods of removal water contents in diesel engine system oils which we have developed and found suitable for practical application.
In the present report we here explain the working orinciple, results of the preliminary test and performance of the apparatus which is produced as an experiment in proper sequence. The principle is evaporated water contents in heating lubricating oils which are occured cavitation by the higher speed revolution of stirrer. The effect of removal water contents was influenced by temperature of oils, revolution speed of stirrer, ratio of surface diameter and height of oils, shape of stirrer and charging way of cleaning air etc..
It was required the treatment time of the measure of 30 minutes at 65-70°C to regular engine oil and of 60-90 minutes at 100-115°C to heavy duty engine oil.
This technical method may be able to make use of removal water contents in turbine oils and hydraulic fluids etc..
We think that the treatment time is still more possible to shorten for none-additive lubricating oils when the condition of treatment will be choosed aptly.

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Torque transmission by loose (non-fitted) bolts is based on friction between the mating surfaces of flange couplings.
Calculation method for loose bolts are indicated in this paper.

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Fuel oil fine filter in front of ocean going diesel engines became necessary to cope with recent residual heavy fuel oil, but flow capacity of supply pump in fuel oil circulation line are large as compared with fine filter flow capacity. There for, we can not equip the filter in front of main engine.
Oxdated asphaltic hard carbon and sodium chloridize became generally most in fuel circulation line by superheating.
This report gives how to cope with heavy fuel oil by small changeover of fuel oil supply pump.

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