Recently, personal mobility vehicles with electric motor have been attracted attentions. Especially, electric skateboards have some good points for fuel efficiency and portability. However, it is difficult to keep standing on electric skateboard. Although it is needs a human dynamics model during standing in order to improve riding comfortability, there are not any suitable models in past studies. Therefore, this study tries to build a human body model on sagittal plane with frequency response experiment.

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The sterEOS X-ray machine is capable of a simultaneous capture of biplanar X-ray images by slot scanning of the whole body in physiological load-bearing position. The simultaneous capture of spatially calibrated anteroposterior and lateral images provides a three-dimensional (3D) surface modelling of the skeletal system using sterEOS 3D software. The relevant clinical parameters such as spinal and pelvic parameters are supposed to be measured. The aim of this study is to evaluate an accuracy of EOS measurement on spinal alignment. A phantom for X-ray imaging was used for CT scanning and sterEOS X-ray imaging. 3D surface models of a phantom were reconstructed from its CT images. The same clinical parameters measured from CT-derived 3D surface models and sterEOS 3D software were compared.

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Galvanic vestibular stimulation is to give stimulus into the vestibule by passing a direct current between the electrodes mounted on back ears. This stimulation causes acceleration sensation and inclination of the body. This study investigates quantification of acceleration sensation with galvanic vestibular stimulation. Especially, the movement of center of gravity by galvanic vestibular stimulation and that by applying the force corresponding to the acceleration to the head are evaluated. As a result, there are individual differences in the movement of center of gravity by galvanic vestibular stimulation.

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From an increase in the aging rate, it has been proposed various Watching System. Tracking System is that even a small burden in measurement in a long time has been required. From this kind of circumstance, we developed wearable device which is easy to wear and possible to measure physical motion and activity for a long term, and evaluated the physical activity in daily life by using this device in this study. This device is made by conductive yarn. This material shows the superior breathability and flexibility. In the experiment, our device and its system are able to recognize about 8 human motion with 90% of correct answers. From this result, it is considered that system is useful for patient monitor.

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To develop the power generation system using the magnetostrictive material and the vibration in the flowing water, we focus on transverse-galloping vibration for a rectangular prism with a critical depth section of less than 0.6. Free-vibration tests of two cantilevered rectangular prisms with side ratios of 0.5 and 0.2 in a side-by-side arrangement were performed in a water tunnel to investigate the effects of the gap between two prisms on the flow-induced transverse-galloping vibration and the performance of vibration power generator using an iron-gallium alloy that is a kind of magnetostrictive material. Rectangular prisms with a side ratio of 0.2 vibrate only the characteristic frequency of a prism, and the gap ratio between two prisms has little influence on the response characteristics of vibration. The response characteristics of vibration and the frequency of the rectangular prisms with a side ratio of 0.5 are dependent on gap ratio. The maximum electric power using the rectangular prisms with a side ratio of 0.2 arranged with gap ratio of 0.5 was 10.8 mW at a reduced velocity V_r=2.6.

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The three-dimensional compressible Navier-Stokes equations are numerically solved to study the transitional structure and the resultant acoustic emission in a supersonic round jet at high convective Mach numbers. Numerical results for the convective Mach number M_c = 1.00 (M_j=2.0) and Re_<r0>=2000 based on the jet nozzle radius r_0 are presented. Four different cases were investigated. These cases are the jet flow forced by random disturbances with various dominant wave length λ_<max>. These results suggest that the random inlet disturbance with short wave length affects transition largely compared with long wavelength. However, in the case where the potential core length is the same, the effect of dominant wave length of inlet random disturbance on transition structures and sound fields is small in the super sonic round jet.

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