Wind power as renewable energy has been come into the limelight by global warming and energy problems, and small type of wind turbine has been settled in general home and company. However, the widely used wind turbine is ordinary propeller type, and there is more complicated technique at the field of producing its propeller type of blade. From these causes, we proposed a new type of wind turbine having the possibility of easy producing the wind turbine blade as a new next generation wind turbine type. Concerning the rotation of falling maple seed in the nature world, its blade can be produced as a new type wind turbine blade from the phenomena, and the production is so easy as to prevent the twisting with taking wind' s streamline into account. In the present experiment, as long as 130 mm turbine diameter, we compared its electric power and rotational speed obtained from the wind turbine generator among installation conditions of the kind of blade shape, the settlement angle, and the number of blades. They are varied by the conditions, and there are the most suitable conditions.

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   This paper presents the experimental investigation of characteristics of a maple seed type small size wind turbine with about 70 cm turbine diameter. It can be settled widely in any home and company. However, the popularly used wind turbine is ordinary propeller type, and it needs more complicated technique especially at the field of producing the blade. From this cause, we have proposed a new type of wind turbine having the possibility of easy producing the wind turbine blade, maple seed type blade, concerning the rotation of falling maple seed in the nature world. As long as the use of the wind turbine, it can be effective to be utilized such a small size wind turbine that would be settled in a duct at home or company with the circumstances of swirling wind. We dealt with the blade having 70 cm diameter at the wind area of the wind turbine, which is larger than our previously investigated one. We obtained the results that its power coefficient to tip speed ratio changes by the installation conditions: the kind of blade shape, the number of blades, the radial position of the blade installation and the existences of wind cover and wire jointed between the blades.

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   The widely used wind turbine blade is ordinary propeller type one, which needs more complicated technique for producing its blade. To solve these difficulties, we propose a new type of wind turbine blade having the possibility of easy production of the blade as a new type of horizontal small size wind turbine. Concerning the rotation of falling maple seed in the nature world, its blade can be produced as a new type wind turbine blade, and we prevent the twisting from producing the blade with taking wind' s streamline into account. In the present study, we used larger blade than our previously investigated ones, and its electric power and rotational speed are compared by changing the conditions of installation of blade, the blade shape, and the settlement angle. It is clarified that they vary according to those conditions and that there are the optimum properties of the blade.

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   At the present study, we clarified the power characteristics and the transient response of the power in a small type wind turbine at about 1.1 m diameter of wind receiving area having maple seed type blades in a great wind tunnel experimentally. We have proposed a new type of wind turbine blade having the possibility of easy producing the blades which are imitated the rotation of falling maple seed in the nature world. At the previous study, we dealt with the wind turbine at 0.13 m diameter of wind receiving area. At this case, we clarified the wind turbine has larger power experimentally. At this present, we used maple seed type blades made of CFRP because we kept the blades strength by becoming larger diameter of wind receiving area. We obtained its power and rotation from the wind turbine generator among experimental conditions of the blade installation angle and the blade rigidity. By comparison, they vary by the conditions, and there are the most suitable conditions. We also obtained the result that its transient response to the wind at the maple seed type blade is better than that at the ordinary propeller type blade.

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   The purpose of this study is to clarify nonequilibrium condensation of the refrigerant HFC134a vapors on shock tube wall behind both incident and reflected shock waves. The diaphragmless shock tube with cooling by liquid nitrogen has been utilized for the experiment at low temperature. We set initial temperature of driven gas 190~220K and set incident shock wave Mach number 2.0~4.0.Thickness of condensing liquid film is measured by optical interferometric method based on multiple reflections of He-Ne laser beam. Heat flux of wall is also measured by Platinum thin film thermo-sensor. As the results, shock wave characteristics in test fluids nitrogen and HFC134a are clarified.. It is also found that growth of the liquid film thickness of HFC134a depends on the nonequilibrium degree of pressure. For the measurement by Platinum thin film thermo-sensor, the values of heat flux are bigger when liquid film grows faster. and heat flux values have rapid increase behind reflected shock wave.

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   In 2004, many large-scale fires occurred in Alaska and the burned area encompassed about 26,700 km². This was the largest burned area since 1956, and combined with an additional 19,000 km² burned in 2005 (third-largest fire year), the total burned area comprised about 10% of the Alaskan boreal forest in just two years. To clarify the background of the many large-scale fires in 2004, spatial and temporal analyses using various data were performed in this paper. The derived results allow the following conclusion. Dry and warm weather conditions with strong persistent winds are crucial for fires. In 2004, easterly winds from Canada caused two daily hotspot peaks in late June and late August; one daily hotspot peak in mid-July was caused by southwesterly winds from Bethel or the Bristol Bay. These persistent winds lasted for about one week and promoted fire expansion. The above wind conditions in June and August were caused by the development of a high-pressure system over the Beaufort Sea under a persistent blocking ridge over Alaska.

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   The purpose of this experimental study is to check the characteristic of the water flow including air bubbles to control thickness of the cake layer in membrane filtration using the flat sheet MF membrane. The experimental equipment is comprised of the water tank which can simulate water flow including air bubbles on the surface of the flat sheet MF membrane, the aeration pipe with 6 downward aeration small holes through which air would spout out to the water tank and the PIV(Particle Image Velocimetry) device to visualize the water flow including air bubbles. From the result of the experiment, we clarified that the water flow including air bubbles on the flat sheet MF membrane above the aeration pipe was greatly influenced by the angle that the aeration pile and the water streamline below the aeration pipe made.

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   In this study a new type of air lifting tower was assessed. This type was first installed in a reservoir in 2009 and employs diffusers continuously emitting air. It is expected that its configuration will provide several competitive advantages over the conventional intermittent type. Field tests were conducted at the reservoir to assess its water circulation performance. The water flow velocity was measured near the reservoir surface above the tower in winter and the flow rate of the lifted water was determined. The measured flow rate was compared with that predicted numerically. In the following summer, the temperature distribution in the reservoir water was measured with three new identical towers operating and compared with data obtained when six conventional towers were operating. The flow rate of the water lifted using the new tower was found to exceed the predicted value by approximately 30%, and the temperature difference between the reservoir surface and the bottom was less than or equal to 10°C in August, which is lower than that achieved using conventional towers. Moreover, the power consumption of the three new towers was less than 50% of that of the six conventional towers.

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   The three dimensional displacement of wrinkles in a thin film caused by tension and shear displacement was measured using the digital image correlation method. First, the measurement technique based on in-plane displacement of two cameras was demonstrated using a steel plate. Next, the three dimensional displacement of the wrinkles was measured. The concavo-convex form of the wrinkles agreed well with the out-of-plane displacement obtained by this technique. The inclined angle of wrinkles was close to the direction of the first principal stress calculated by the theory of elasticity. Therefore, the compressive strain that occurs in the direction perpendicular to the first principal stress direction may cause wrinkles to the thin film. The amplitude and wavelength of wrinkles which were calculated from the scaling law in consideration of the principal stress direction generally agreed well with the experimental results. Moreover, the absolute value of principal stresses calculated from the measured displacement became large in the local portion of the concavo-convex form in wrinkles.

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   Image analysis with ultra-high-speed camera is applied to the unstable crack growth under quasi-static uniaxial compression. Stress field around the moving crack tip in the transparent specimen is visualized by means of photo-elastic technique and images of growing cracks and the stress field are captured with the frame rate of 250,000 fps. As a result, it is revealed that wing cracks start initiation at each end of the initial defect with time lag, and the time difference in their initiation corresponds to the travelling time of the stress wave, which is released due to the growth of the primary crack, from one end of the initial defect to the other end.

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