A detecting method on quantity and oil existence in a model tank using ultrasonic pulse echo method have been assuming the remained oil inside sunken ships. C scope which is one of the method of the pulse-echo method was used for the construction of image. This experiment showed that the measurement of the remained oil inside the sunken ship was possible using ultrasonic pulse echo. The goal of this research will be the establishment of this technology to can measure remained oil inside sunken ships quantitatively and three-dimensionally by tomography-method using many measuring points.

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Two kinds of swirling flow are generated in a main vertical pipe by using two kinds of air inlets. A rod-like material is put into the main vertical pipe. Four optical sensors are attached to the main vertical pipe. When the rod-like material is sensed by the four optical sensors, laser sheet is irradiated and the image is obtained by 3D-PIV. It means the posture of the rod-like material is upright and rotating with orientation. However, when the rod-like material is sensed by the two optical sensors, it means the posture of the rod-like material is not upright and rotating without orientation. Two images obtained by the above-mentioned were compared to derive the condition for the rod-like material to rotate at the constant height in the main vertical pipe, and the flow field around the rod-like material is analyzed by modal wavelet transform.

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Active control of jet is applied at control of burner flame or air-conditioning. In this study, secondary film flow is built on the outside of axisymmetric jet. And it is driven by the acoustic excitation for active jet control Furthermore, the velocity ratios of mainstream and film flow and acoustic Strouhal number were changed. The jet structure was visualized by LLS in axial and cross section for research of change in each jet ejecting condition. As a result, it was confirmed that the velocity ratio of film flow influenced to outbreak and growth of vortex ring corresponding with shear stress with surrounding air, and the acoustic excitation influenced to outbreak period of vortex ring in film flow. And it was presumed that there were both modes which rolled up to the mainstream or surrounding air by frequency of an acoustic wave to give. For controlled jet, it was confirmed a mutual interference process of vortex ring and the blade which were base of the vortex structure of jet.

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Flow visualization of an inscribed gear pump is carried out to grasp the influence of deformation rate and the rotation of the fluid chamber provided by the two trochoid gears. A transparent model of the pump, which resists friction, is made. A platelet type of light-reflecting tracer particles "Kalliroscope" is adopted and applied to the visualization of flow patterns. Upon taking phase-statistic for the time serial images, the dependence of the flow on Reynolds number is evaluated.

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In order to reduce costs, speed-up in a suction sump is recently suggested. However, it is predicted that excess speedup causes air entrainment and performance of a pump goes down. In this paper, air entrainment caused by speedup in a suction sump is investigated. Recently, in order to speed up development time and reduce development cost, CFD technique is often used. So, investigation was carried out by using CFD analysis. The occurrence of air entrainment was checked by void fraction.

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A highly-efficient mixing process would be expected by using a micro channel owing to increase in the specific interfacial area. However, in micro channels, there is no turbulent diffusion because Reynolds number is usually low and the flow is laminar. In the present study, to improve the mixing process in a Y-shape micro channel, a highly oscillatory flow was supplied, and the mechanism of the process is clarified based on numerically as well as experimentally.

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Rapid mixing is essential on the micromixer in microfluidic systems. Mixing in microchannel relies mainly on molecular diffusion due to the laminar flow at low Reynolds number. In this study, the sequential switching of electroosmosis flow is applied to the mixing in microchannel. By switching of the electroosmosis flow sequentially to the T-junction microchannel, the mixing stream is segregated by the two inlet streams on and off, then the mixing process can be accelerated and controlled by increasing the contact surface of two liquids. In this report, the velocity and concentration fields were measured simultaneously by Rhodamine B and tracer particles of 1.0μm diameter suspended in the water.

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We have developed a confocal micro-PIV system that enables us to measure and visualize the velocity field in a thin planar region of micro flows. The confocal slice images can be captured with up to 2, 000 fps using the high-speed laser-scanning confocal microscopy and a high-speed camera. We can measure the micro flow in the horizontal region of 240 μm x 180 μm with the in-plane resolution of 9.6 μm x 9.6 μm and the out-of-plane resolution of 1.9 μm using the present system. The confocal micro-PIV system is applied to the internal flow measurement of a small droplet that is transported in a square microchannel with the size of 100 μm x 100 μm. The result shows the fluid inside a droplet circulates three-dimensionally and intricately.

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Electro-thermal analysis of Si CMOS is performed. In order to have a higher degree of integration, the distance between two MOSFETs in CMOS structure must be decreased. But decreasing the distance between two MOSFETs results in an electrical interaction. In this research, we examine the interaction mechanism between n-type MOSFET and p-type MOSFET in Si CMOS in transient state. Numerical results show that the reason of the interaction between two MOSFET in CMOS is the forward bias at the pn junction with the substrate and that the timing of interaction becomes earlier and the leakage current increases as the distance between two MOSFET decreases. Furthermore, we investigate that the timing of interaction becomes later and the drain current decreases as the temperature of CMOS increases.

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When a laser beam irradiates a sample, a small amount of the incident energy is locally absorbed by the sample along the laser beam. When this local heating occurs, the refractive index of the medium also changes locally along the beam, and the entire medium acts as a lens. This effect is called thermal lens effect. Recently, the application which uses the thermal lens effect to the density measurement etc. starts, And near future, the device which switch from light to light without changing electricity will be expected. In this research, we discuss about various wavelength and modulation frequency noting the expansion for the light switching device using for wavelength division multiplexing and femto second spectroscopic measurement.

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We investigated the feasibility of a self-cooling mechanism, in which refrigerant in a sealed container is heated by waste heat, a turbine is rotated by the vapor generated, and the rotational force is extracted using a magnetic coupling, which in turn is used to rotate a cooling fan. As a result of repeated improvement of the prototype apparatus, circulation of the refrigerant in the apparatus was confirmed. By increasing the pressure differential between the heat chamber and the refrigerant receiver using a nozzle with optimum bore size, a rotor with an inner ring inside the chamber providing a magnetic coupling to an outer magnetic ring outside the chamber was successfully rotated. The above verified the validity of the system's principle.

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High-frequency inductors are one of the most significant loss contributors in switch mode power supply. However, in making the thermal flow simulation model, it is difficult to model a detailed structure of the high-frequency inductor part such as a choke coil and a transformer due to the calculation cost. Therefore, to find the compact modeling method of an inductor part for switch mode power supply, we investigated the effect of proximity losses which occurs close to the air gap, and the effect of anisotropic effective thermal conductivity in inductor windings on the inductor surface temperature.

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Experimental study on enhanced forced cooling of electronics device using heat transfer from a printed circuit board has been conducted. Flow field in the electronics casing model was visualized and measured using a PIV. The existence of the stagnation regions upstream and downstream of the heater element on the printed circuit board was confirmed. It is shown that flow condition and velocity profiles over the heater changes depending on the flow rate.

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In the numerical analysis using the spreadsheet of Excel, the image of the physical model can be drawn on the worksheet, and both programming and debagging are performed visually via classification by coloring of interior and boundary cells, where corresponding difference equations are embedded. Furthermore, calculated results can be shown and at the same time confirmed immediately by using the accessory graph wizard. In the present study, a newly developed visual-oriented numerical method for solving the two-dimensional steady-state mixed convection problem which applies the upwind-difference scheme is explained through a simple physical model of inclined parallel plates with discreet heat sources.

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In the numerical analysis using the spreadsheet of Excel, the image of the physical model can be drawn on the worksheet, and both programming and debagging are performed visually via classification by coloring of interior and boundary cells, where corresponding difference equations are embedded. Furthermore, calculated results can be shown and at the same time confirmed immediately by using the accessory graph wizard. In the present study, a newly developed visual-oriented numerical method for solving the two-dimensional steady-state forced convection problem which applies the simple method is explained through a simple physical model of inclined parallel plates with discreet heat sources.

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It is said that the Jomon Age began about12, 000 years ago and continued till about 2, 500 years ago. The potteries of that age are known as Jomon pottery. Among them, a pottery discovered from the Umataka ruin in Niigata Prefecture in 1931 has an excellent shape. It is said that this pottery was made about 4, 500 years ago. Jomon potteries of similar artistic styles have been discovered in various parts of Japan. These potteries have very nice shapes, but the pottery discovered from the Umataka ruin excels other potteries by its excellent proportion. From the shape of lip, it was named "Kaen pottery" meaning " flame pottery" . However, from the patterns of its lip and side wall, it is more appropriate to consider that they are related to water flow. In this report, this hypothesis by a visualization method using the pollen of cedar and pine trees, and computer simulation.

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Rhythmical movements have such characteristics as "wholeness", "rhythmical flow" and "harmony". They are also characterized in the central movement theory. In the central movement theory, movement should flow from the center of the body to the peripheral parts of the body.
A snapshot of these rhythmical movements gives the impression of space, time and dynamics of a movement flow.
In this study, the rhythmical movements flow was visualized by anaglyph stereo image taken by two color CCD cameras side by side. Effective applications of anaglyph stereo image to the field of movement education were discussed in this research. Anaglyph stereo image helps the understanding of the movement structure especially for the advanced gymnastics course students.

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In this paper, the three-dimensional-image recognition of rhythmical movement was studied by using the stereoscopic observation system. The method is described for generating the stereo images at each camera position. An example of the stereo images is shown for the moving body under rhythmical movement.

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In rhythmical gymnastics, movement should flow from the center of the body to peripheral parts of the body. VTR, DVD and photographs are used to teach the movements. The purpose of this study is to compare the impressions of anaglyph stereo images and 2D images using a questionnaire. The stretching and stability of a hard to understand movement was better perceived via anaglyph stereo image. For simple movements, anaglyph stereo images revealed dynamics more effectively than 2D images, but were less effective at revealing relaxing. This suggests that anaglyph stereo images are effective tools for analyzing movement in rhythmical gymnastics.

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The behavior of the baby Brine Shrimps in a group is investigated by using tracking method in this study. Loci of individuals express extent of behavior and speed of motion. Each area drawn by them shows mutual interaction of their motion. This picture after image processing is so beautiful that it looks like an artificial painting.

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This paper examines the effect of artistic color moire generated with color stripes and monochrome fringes in science education. The color moire fringes are sure to be useful for introductory science education because the color moire fringes are easy to generate and they are magical and attractive for inexperienced young people and furthermore the moire fringes can visually express the phenomenon of wave interference. The generation of the color moire fringes is mathematicallyy expressed to show that each color moire fringe is independently positioned in moire space. This paper also shows the way to generate the original color and monochrome stripes on a personal computer with a software uploaded on our Web page and it examines the influence of the fineness of the stripes printed on a sheet of OHP films or papers on the resulting color moire fringes. Finally, it introduces a color moire viewer to observe fantastic color moire through a rectangular window on the viewer.

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A variety of kinds of binocular vision devices have come to be offered at a low price. However, even if the price becomes cheap, the problem that it is necessary to set up a special device cannot be avoided. On the other hand, the monocular stereogram has been researched in the field of recognition from of old. Man can obtain the 3D appearance by physiological factors and experienced factors: We thought that we were able to raise the 3D appearance by paying attention to motion parallax in that, and vibrating the image in 3D even on a usual display. A result of executing examination, it understood that the method of the presentation as the animation that changes timewise can correctly recognize the 3D geometric shape from the method of sideways arranging two parallax images.

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This paper presents the measurement method of detecting orientation of flying objects based on digital holography. Using the in-line observation system with an electronic camera in this paper, the 3D volume of light intensity is numerically reconstructed from the digital hologram captured on this system. The orientation is measured from the object positions detected using the information of the gray level gradient higher than a certain threshold, and then the translation and rotation of flying object are detected from a time-series of digital holograms. In numerical simulation, representing the object of rod as discrete and small parts linked in line, it is found from the simulation results that the RMS error is evaluated to be 0.1mm. The accuracy of the present method is visually demonstrated by comparing true position with detected one.

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This paper reports a newly designed visualization API (Application programming Interface) for a Cartesian and octree data structure which allows us. to render and visualize the data efficiently. It is designed that this visualization API is consists of a window frame class, a scene-graph class and a visualization function class. The window frame class is constructed from wxWidgets, which is open source GUI system, so as to be operated on major platforms such as Linux, Windows and MacOS X. As concerns the scene-graph class, we developed an original API instead of the standard sene-graph library like VTK because of seeking of the rendering efficiency and supporting the special data structure. Based on this API, a rendering application was developed and evaluated. This data viewer will be delivered from RIKEN.

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Large eddy simulation was performed for flow and heat transfer under stable density stratification in a wavy wall channel to reveal the effect of stratification on turbulent structures. Low-Mach-number approximation was applied to treat density variation. The iso-surface of instantaneous temperature in the middle of the channel shows that the effect of stable stratification is strong and greatly reduces turbulence there. On the other hand, instantaneous structures and two-point correlations near the wavy wall suggest that characteristic near-wall structures and their scales are not strongly affected by the extent of stratification in spite of considerable reduction of turbulent intensity.

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Large-scale simulations on two-phase liquid film flow in an advanced nuclear reactor were carried out and the results were visualized numerically. An analytical geometry is a three-dimensional narrow rectangular channel in which a fuel channel of the advanced nuclear reactor was simply simulated. A liquid film flow was set to the channel inlet. The lower part of the channel inlet is the liquid phase and the upper part is the gaseous phase. Calculations were conducted with parameters of liquid film thickness, fluid velocity, heat transfer on the bottom wall, etc. The spacer effect to the heated liquid film flow was observed. A series of the present results were reflected in optimization of spacer configuration.

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