This Experimental study has been made of two-dimensional visualization on the soot particle and NO concentration profiles in the steady and non-steady flames by laser sheet. The soot volume fraction (maps) can by determined from LLS (Laser-Light Scattered) method on the basis of the data obtained from Light Attenuation Method. NO concentration have been measured by the Laser-Induced Fluorescence (LIF) . The soot volume fraction lies within the limits of 10^-7 and 10^-5cm³/cm³, and have maxima at the inside part of ribbon flame. The soot decomposition is risen acceleratory together with eddy break down at the down stream zone. It is found from the observation by LIF that NO formation tend to occur at the condition of high temperature zone for the flame cross-section area. Good agreement is achieved for the relative NO concentration profiles by LIF method, and the absolute concentration profiles by sampling method.

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The application of alcohol blended fuel is one of effective methods to control the exhaust emissions of diesel engines. But the combustion characteristics of this fuel is not so clearly analyzed.
This paper shows the behavior of this droplet in a constant volume chamber by using of a laser speckle interferometer. First, we noted about the application for measurement of the temperature field owing to a Bunsen burner flame by a two-exposure system, and then we noted about the application to the analysis of a droplet combustion. The weak point of this system was difficulty to get clear speckle photographs, because the speckle fringes are obstructed by the strong illumination from the combustion flame.

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In recent years, an electronic-controlled system has been widely used for the engine.
The authors developed a new system using hydraulic-actuated mechanisms, and applied to the fuel injection control and the drive control of the suction valve/exhaust valve of the mediumspeed four-stroke test engine.
Then, it was applied to the fuel injection control system and the exhaust valve drive system of the large-sized two-stroke test engine, and it was confirmed that it is possible to achieve the same or higher engine performance as compared to the case with conventional cam system.
Moreover, combining “Electronically Controlled Exhaust Valve system” and “Scavenging Controlled Valve system” as a mechanism of a new concept, the authors were able to control freely the scavenging air and exhaust timing of engine. As a result, the effective work of the engine was increased, and the specific fuel oil consumption was improved by 8g/kwh.

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Floating lining system has been employed to reduce noise level in cabins. However, the noise reduction level is approximately 10dB (A) and it is not satisfactory. Therefore, more effective system is desired to be realized. This paper presents the reason why the conventional systems have poor effects and shows the techniques to improve the effects. The present system is consist of a box made of four lining walls and a ceiling set on a floating floor, and the box has no connecting points to the steel structure except a few rubber pieces. Experiments with the presented system were carried out by using a scale model. Employing the new system, the vibration level on the lining could be the same level as the floating floor and the vibration level of the lining is more than 10dB lower than the conventional system in wide frequency ranges.

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