A new method to actuate a small droplet on a plate is proposed. A laser beam is irradiated on one end of the droplet set on a SAMs (Self-Assembled Monolayers) plate. Since the wettability at the heated side is improved remarkably, the tangential component of surface tension pulls the droplet toward the spot of laser beam. In this report, the resultant force in the tangential direction is estimated experimentally when the droplet starts to slide on the plate. In order to obtain the temperature dependence of contact angles, the axi-symmetric droplet profile is measured while irradiating the laser beam homogeneously over the droplet. The temperature is estimated from the surface tension determined from the comparison between the solution of Laplace equation and experimental droplet profile. Based on the measured temperature dependence of contact angles, the resultant of surface tension acting on the circumference of droplet is calculated at both ends of droplet when the laser beam is irradiated on the one end. The calculated results show that the resultant force is actually positive and rapidly increases when the droplet starts to slide.

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   Flow through an air passage of ventilated automotive brake rotor affects the thermal energy dissipation from rotor into atmosphere. In the present work, a velocity profile around a ventilated brake disc was measured using a hot-wire anemometer in order to understand the statistical turbulent property of air passage flow. Three-dimensional velocity components were evaluated at 5 mm outside the disc edge by rotating X-type hot-wire probe. The probe was also tilted corresponding to rotational speed so that it could receive the maximum velocity from disc. The maximum value of both average and fluctuation velocity increased significantly than that of solid disc. The velocity fluctuation profile indicated asymmetric aspect in contrast to the average velocity profile. An empirical one-dimensional model was suggested for evaluation of flow through air passage. The predicted radius velocity agreed with the present experimental results by substituting local angular speed of disc into air circumferential velocity.

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   In this paper, we present two types of CTA circuits which consist of a bridge circuit and a feedback circuit. One circuit uses only one operational amplifier and the ratio of the electrical resistance of the Wheatstone bridge is set to 10. Another one uses three operational amplifiers and two of them have bigger gain-band width product and slew rate, and its ratio of the electrical resistance of the Wheatstone bridge is set to 1. Velocity measurement results in a planet jet and a square jet show that there is no noticeable influence on the measured mean streamwise velocity and RMS value of the streamwise velocity fluctuation by the difference of the circuit in a CTA. However, it is found that the frequency response of each hot-wire anemometer is different and this causes the difference of the range of the non-dimensional streamwise wave number where obeys the reliable numerical energy spectrum derived by a LDIA (Lagrangian Direct-Interaction Approximation) theory.

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   In general, a separated flow involves a reverse flow near the solid surface and its re-attachment in the downstream region. Therefore, the velocity measurement techniques, which can detect only the magnitude of the flow velocity is not useful to measure the separated flows. From this background, a tandem-type hot-wire probe which can detect not only the magnitude but also the direction of the flow is made and used to measure a separated flow around a two-dimensional blade. The tandem-type hot-wire probe consists of two I-type hot-wire probes and a small elliptical-shape resinic cylinder. A careful calibration test and the preliminary experiments are performed to confirm the validity of the self-made tandem-type hot-wire probe. The measurement results show that the characteristics of the separated region can be estimated precisely, and the re-attachment position obtained by the tandem-type probe is almost the same as that obtained by the static pressure fluctuation at the blade surface.

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   Acceleration of liquid mixing in micro channel can further reduce the analysis time and the size of analysis device. While the acceleration leads to better performance of microreactors, measurement methods for its evaluation are limited and insufficient. The developing measurement methods of the concentration distribution of reaction product in micro channel are conductive to evaluation of the mixing performance of microreactors and to visualization of the reaction process in microreactors. Therefore, the measurement method of product concentration distribution in microreactors are proposed and evaluated in the present study. The distribution of reaction product, [Fe(SCN)₂]⁺ (blood red) which is produced by reaction between Fe₃⁺ (yellow) and 2SCN^- (colorless), is measured by detecting the intensity of transmitted light using a color CCD camera. Applying two-color method in the concentration measurement is shown to significantly reduce uncertainty due to fluctuation of backlight. The best color combination to take intensity ratios is found to be green and red because it can avoid measurement error due to the misrecognition of reactants as low concentration products.

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   A new method is proposed for investigating the propagation characteristics of a sound wave and a sound source in a flow. This is achieved by measuring the static pressure fluctuation in a flow using a lock-in-amplifier. The static pressure fluctuation in a flow is measured by using a very small static pressure probe consisting of a thin pressure tube with 8 static holes on its wall and a 0.1-in microphone set into the flare of the probe connected to the tube. The present method is found to accurately identify the propagation direction of the sound in a flow. It also detects two types of different sound sources that originate from the Karman vortex streets behind a cylinder and holes installed in it.

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   A new type of wave power generation system is proposed to be installed in a vertical slit type breakwater. The merits of the system are listed as follows. (i) no occupation of the sea surface, (ii) maintenance facility, and (iii) high energy efficiency by using accelerated flow from the slit of breakwater. In this study, several kinds of water wheels are examined to be installed in a model wave breaker with 1/12 scale ratio to the actual system. The experimental results show that the drag type water wheel (Savonius wheel) has a higher performance compared with the lift type (Darius wheel), since the latter is not accelerated sufficiently during relatively short period of the sea wave. Based on the result that the drag type is favorable, a new generator is proposed to perform higher efficiency. An elastic rectangular plate connected to a wheel and axle via a string is set in the water. When the wave drag bends the plate, a tension appears in the string and it rotates the wheel connected to a generator. The performance of bending plate generator is examined under various experimental conditions. The results show that a soft textile with zero elasticity has the highest performance. The output per occupied sea area is expected as 23,500(W/m²) in the real system, which is much higher than other types of generators treated in literatures.

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   The main role of conventional safety helmets is to protect the human head from external forces. So far the design of standardized helmets has placed an excessive emphasis on mechanical performance from this standpoint. During wearing the helmets, users experience high temperature rise in the head as well as excessive perspiration and an oppressive feeling. These discomforts prevent users from wearing the helmets. Behavior of air flow around the helmets needs to be studied in order to examine air cooling effects while users wear the helmets. Several techniques such as smoke wire, tuft and smoke injection methods have been applied to visualize air flows around the helmets which a mannequin wears in a low-velocity type wind tunnel. The pressure distributions on the outer surfaces of the helmets are measured on pressure transducers using diffusion type semiconductors. The stream lines and pressure distributions on the outer surfaces of the helmets are clarified by the present experiments. It is expected that the helmets are designed more rationally based on both fluid mechanics and the present experimental data.

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   In order to cope with the unprecedented aging society, elderly person need to support themselves and maintain their health. Although there are many electric vehicles such as electric wheelchairs or senior cars, few of them maintain the health of elderly person. They sometimes restrict elderly person sphere of activity of daily living. From such a background, we have developed of four-wheel type electric power-assistant personal mobility for care prevention. In order to check the performance of mobile support equipment, we have experimented for six healthy male subjects using this equipment. The purpose of this experimental is to evaluate the physical load of user by the oxygen uptake values, heart rate and EMG activities while they are running a flat road course and 8% slope. These results can be used for the development of mobile support equipment and evaluation methods.

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   High-efficiency technology to the photodiodes has become a critical issue. Surface plasmon resonance (SPR) would be one of the means for solving the problem. Photocurrent of photodiodes is enhanced by metal nanoparticles, which induce the localized SPR, deposited on light-receiving surface of the photodiodes. Most previous studies had been focused on the photocurrent enhancement effect around maximum absorption wavelength of the nanoparticles. The effect except the wavelength has not been paid attention yet. For instance, in case of a solar cell, metal nanoparticles which have maximum absorption wavelength at around 500nm, have been widely employed since solar light has higher illuminance around 500nm. However, the photocurrent enhancement effect of the nanoparticles has not studied around near-infrared light though illuminance of the near-infrared light is quite valuable. Therefore, in this study, experimental investigation of photocurrent enhancement effect was conducted using Au nanoparticles with 100 and 150nm in nominal diameters, which have maximum absorption wavelengths at around 500nm. As a result, the photocurrent enhancement effect was obtained at near-infrared wavelengths. In addition, higher enhancement effect was achieved when the two Au nanoparticles were mixed. This would be ascribable to obtaining wider bandwidth of maximum absorption wavelengths due to mixing of different-size nanoparticles.

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   Recently, a study to evaluate the eyesight function by measuring the wave aberrations of lens has begun to improve the quality of vision. When the spectacle lens is fixed with the rim, lens strain occurs if the shape of contact surface dose not fit each other. In this study, the influences of the lens clamping of full-rim spectacle on the lens strain were discussed. Three kinds of plastic lenses which are different in the lens diopter with aspect ratio of 1.4 are retained to the same frame and these lens strain are evaluated by experiments and finite element analysis. As a result, we found that the strain of backside of lens was bigger than the face of the lens and the strain of myopia spectacle (-6D) was the biggest than myopia (-3D) and far sight (3D). Furthermore, we found that the equivalent strain of the lens eyes axis decrease dramatically when the Yagen angle of the lens backside of spectacle for myopia became bigger 2 degrees than the conventional angle.

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   In this study, the development of a greening plant consists of moss and a ceramic base material made from clay and waste GFRP was attempted. First, a ceramic base material was made from clay and GFRP. From the result of the bending test, it was confirmed that the base material was satisfied with the standard of strength determined by Japanese Architectural Standard Specification. Second, as a method for producing of the moss plant, moss with size from 2mm to 20mm was distributed over the surface of the ceramic base material in which an adhesive was soaked. From observation, it was also confirmed that moss could root directly on the ceramic base material. In addition, the appropriate condition which made the moss plant visually appealing could be obtained. It was also confirmed that the moss plant was satisfied with the standard of weight determined by Japanese Building Standards Act. Finally, the effects of decreasing of radiant heat and CO₂ concentration for the moss plant were examined. From the results, the usefulness of the moss plant was clarified.

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   When the relationship between the dimensions of face form and those of spectacle frames is poor, it may cause problems such as slipping frames and sore areas on the nose and behind the ears. This paper reports the results of mechanically modeling the contact conditions in the vicinity of the nose. We created a CAD model of a human head by considering the skin thickness distribution. We then performed finite element method (FEM) analysis about the contact region between the pad and the skin. As a result, the nose pad is pressed down in the nose while slanting toward the lower part of the nose gently. Furthermore, the pad is fixed by a slight upsurge by the reaction of the imposition of the skin.

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   The fluctuating load detection plate is a force measurement sensor developed by the authors. In this study, the performance of the load detection plate is investigated by the drop tests using bowling ball and lead ball. Then, by the use of compact drop test equipment, double-strike phenomena induced by the test of weight drop to the surface of flat oil clay and by the test of weight drop to the component made from sponge rubber and cover plate are examined. Further, double-strike phenomenon is examined by the falling test of longitudinally turning bar onto round plastic stick.

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